To see the other types of publications on this topic, follow the link: AOD.
Dissertations / Theses on the topic 'AOD'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'AOD.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Eriksson, Johan. "Gränssnitt för AOD-simulator." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-51091.
Full textAbstract:
Att kunna simulera en AOD-process (Argon, OxygenandDecarburization) är i dagsläget möjligt med hjälp av en programvara. En sådan programvara används till utbildning och forskning för utveckling av rostfritt stål. Kobolde & Partners AB är ett företag som äger en sådan programvara. I detta projekt byggs programmet ut för att ge användare möjlighet att simulera en AOD-process med osäkerhet i mätdata. Genom detta kan forskare få ökad förståelse hur processens mätresultat skiljer sig med osäkerhet i mätdata.<br>: Being able to simulate an AOD process (Argon, Oxygen andDecarburization) is possible nowadays with help of software. This kind ofsoftware is used for education andresearch for development of stainless steel. Kobolde & Partners AB is a company that owns this kind of software. This project will further develop this software to enable users to simulate an AOD process with uncertainty in measurement. This allows scientist to get more knowledge how a process measurement results
2
Axelsson, Fredrik. "Stabilisering av Aluminiumreducerad AOD-slagg." Thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74211.
Full textAbstract:
Slagg har historiskt använts som konstruktionsmaterial i olika applikationer. Alla typer av slagg passar inte på grund av otillräckliga egenskaper. Vid produktion av höglegerat rostfritt stål så är slaggen mycket kalkrik, vilket leder till sönderfall på grund av absorption av vatten. Vissa stålsorter hos Sandvik tillverkas med ett tvåslaggsförfarande där en första reduceringsslagg först används för att sedan ersättas av en raffineringsslagg. Denna rapport behandlar förändringar i slaggsammansättning för att förbättra slaggens egenskaper gällande volymstabilitet efter deponering. I synnerhet så behandlas volymstabilitet av reduceringsslagg och om möjligheterfinns att kombinera bra stålproduktion med volymstabil slagg.Projektet har syftat till att kartlägga hur slaggen fungerar i dagsläget med provtagning nära konverter men även hur förändrade sammansättningar påverkar slaggen som svalnar enligt normal praxis utanför stålverket. Slagger som faller sönder av fasomvandlingar har observerats. Slutligenhar en sammansättning som ser lovande ut ur produktionsperspektiv och stabilitetsperspektivhittats. Slaggen blir då stabil även efter försök att orsaka sönderfall i extrem miljö. Vid produktionmed minskad kalktillsats under reducering kan ungefär två tredjedelar av ingående charger somska reduceras med aluminium hanteras. Med en mindre förändring i AOD processen vid reduceringså skulle ca 6000ton/år kunna skiftas från att sönderfalla till att bli stabil.<br>Slag has historically been used as a construction material in different applications. All types of slags are not suitable due to insufficient properties. Production of high alloy stainless steels leads to a slag which is rich in lime, which leads to disintegration due to absorption of water. Certain steel qualities at Sandvik is manufactured with a two slagg procedure where a first reduction slag is use that is replaced with a refining slag. This report looks into changes in the slag-composition to improve the properties in regards to volumetric stability after disposal. Especially it investigates volumetric stability of the reduction slag and if it is possible to combinea production of high quality steel with a stable slag. Further investigations during the project has looked at how the slag works today, with sampling close to the AOD converter but also how different slag compositions affects the slag that is disposed of outside the steelplant with todays disposal routine. Slag that disintegrates due to phase changes during cooling has been observed. A slag composition that seems promising from aproduction and stability perspective has been found. It results in a slag that remain stable even after enduring harsch enviroments. A production with less lime addition during the reduction phase can handle about two thirds of the aluminum reduced steel batches. With this small changein the AOD process roughly 6000tonnes/year of slag could be shifted from disintegration to stable material.
3
Ta-uar, Chay. "Optimization of the AOD stainless steel processing cost by the UTCAS System." Thesis, KTH, Materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143219.
Full textAbstract:
The Argon Oxygen Decarburization (AOD) process is one of the major stainless steel refining routes. Several parameters come into play deciding the outcome of the process. The task focuses on studying an optimized processing in an AOD converter using the UHT’s Converter Automation System (UTCAS)-process control program. The process parameters that mostly influence the process are studied and their effect on the process are analyzed. The 304, 409, 316, 430, 201, 2205 stainless steel grades are chosen for this study. The input temperature, input element content (carbon, chromium, nickel, silica, molybdenum and manganese), input steel mass are varied individually keeping all the other parameters constant and their effect on the process is analyzed. The parameters like process time, amount of gases (O2, N2 and Ar) consumed, amount of reducing agent (FeSi) and amount of alloy addition are taken into consideration to decide the optimal outcome of the process. The number of gas blowing steps is also varied to study its influence on the AOD process. This is done at different process initial input to also study the effect varying parameters on the stainless steel process. After analyzing the effect of all the parameters suggestible range of values for the parameters are proposed for on optimal blowing in an AOD converter.
4
Minor, Dale Michael. "An Evaluation of the completion and Recidivism Rates for a Collaborative Community - College Based Alcohol and Other Drug Offenders Diversion Program." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1188313072.
Full text
5
Myckelberg, Pontus. "Förhindra sönderfall av AOD-slagg under svalning genom förändrad sammansättning." Thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70893.
Full textAbstract:
AOD-slag at Sandvik Materials Technology in Sandviken is disintegrating to a fine powder during cooling as a consequence of a volume increase caused by a phase transformation. The slag becomes a powder that's hard to handle because of dusting, the environment that is closeby take a beating. On top of that the slag must be landfilled and cannot be used as secondary material. In general most slags have a great potential to be used in as construction material in different applications around the society after used by the steel industry. In Sandviks case the disintegration stops that from being possible. To prevent disintegration of AOD-slag serveral things can be done, such as new additives or change of slag composition. In this project a new composition of the slag has been obtained from a decrease of lime addition. Then the slag composition can be moved outside of the area of disintegration by the volume increase. The change had to be done without jeopardize the quality of the steel or the lining material in the AOD. Potential steels were choosen for trials with lowered addition of lime after a present value analysis were established. The early analysis was conducted by slag samples from different steels in the AOD, these samples created the foundation of method further on. The full scale tries were conducted in three campaigns with different follow-ups. The results shows that there is possible to reduce the lime addtive to the AOD and by that receive a solid slag and at the same time produce high quality steel. With reduced lime addition the basicity is lowered. With lowered basicity the results shows that the sulphur removal gets worse as well as the reduction of chromium. The method established in this thesis does no go well with all steels except some pinpointed steel types with less demands on high sulphur removal.<br>AOD-slaggen vid Sandvik Materials Technology i Sandviken sönderfaller till ett fint pulver under svalning som en konsekvens av en fasomvandling av dikalciumsilikat där en volymexpansion sker. Slaggen som blir pulver blir svårhanterlig på grund av att den dammar, närmiljön försämras till följd. Dessutom måste slaggen deponeras och kan inte användas som ett sekundärt material. Generellt anses slagg har stor potential att användas till andra applikationer i samhället efter användning i stålindustrin. I Sandviks fall sätter sönderfallet stopp för det. För att undvika sönderfall av AOD-slaggen kan en rad olika saker göras som tillsatser eller ändring av sammansättning. I det här projektet har en ny slaggsammansättning uppnåtts genom minskning av kalktillsatsen till slaggen. Då kunde slaggens sammansättning flyttas från området för sönderfall genom volymexpansion. Förändringen var tvungen att ske utan att äventyra stålets kvalité eller infodringen i AOD:n. Potentiella stålsorter valdes ut för försök med mindre kalktillsats efter att en nuvärdesbild hade etablerats. Nuvärdesbilden bestod av provtagning av slagg från charger i AOD:n och den bidrog till metoden för försöken. Fullskaleförsöken utfördes i tre kampanjer med olika typer av uppföljning. Resultaten visar att det är möjligt att minska kalkmängden till AOD:n och därmed få en stabil slagg och samtidigt producera ett fullgott stål. Genom minskad kalktillsats sänks basiciteten och det gör slaggen mindre basisk. Resultaten visar att svavelraffineringen blev sämre. Kromreduceringen blev också något sämre. Metoden framtagen i det här projektet fungerade inte för alla stålsorter utan det är framförallt några utvalda stål med lägre krav på svavelrening.
6
Chanouian, Serg. "What If We Tilt the AOD? : Developing a numerical and physical model of a downscaled AOD converter to investigate flow behaviour when applying an inclination." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254912.
Full textAbstract:
In a scrap based stainless steel plant the dominant process for carbon reduction is the Argon oxygen decarburisation process (AOD). The process goes through three steps: decarburisation, reduction and desulphurisation where the main challenge is to oxidise carbon to CO without oxidising the expensive chromium. The general practical approach is to inject a mixture of oxygen and an inert gas, like argon or nitrogen, through tuyeres at the converter side starting with a high amount of oxygen gas which followingly is reduced as the inert gas is increased during the decarburisation steps. This allows for a decrease in partial pressure for the CO bubbles which is thermodynamically favourable for carbon oxidation. Recent studies have shown that an aged AOD converter with a worn lining can decarburise the melt faster than a fresh vessel due to favourable thermodynamic conditions occurring since the bath height is lower in the aged converter. The studies show 8-10% savings of oxygen gas which have led to an interest to study the matter. One of two approaches are taken in the present work with the focus to develop a numerical model that simulates a downscaled AOD converter with applied inclinations that is to be validated through physical modelling. A 75-ton industrial converter was downscaled for water-air experiments where three inclination angles namely 0, 5.5 and 14° were studied with focus on mixing time and penetration length. The physical model was replicated for computational fluid dynamics (CFD) modelling using the Euler-Euler approach in ANSYS Fluent. The models show rather good similarities when comparing gas penetration length, flow structure and mixing time however needs some complementary work and final adjustments before upscaling as well as coupling with thermodynamic modelling can be done.<br>Den dominerande processen för kolfärskning vid skrot baserad rostfri ståltillverkning är AOD- processen (Argon Oxygen Decarburisation). Processen går igenom tre steg, kolfärskning, reducering av krom och svavelrening där de största utmaningarna ligger i att oxidera kol utan att oxidera krom. I praktiken gör detta genom att injicera en blandning av argon och syrgas från sidan av AOD-konvertern för att sänka partial trycket av den kolmonoxid som bildas när kol oxideras. Syftet är att göra det mer termodynamiskt fördelaktigt att oxidera kol i systemet. Den injicerade blandgasen har olika förhållanden under kolfärskning med en hög andel syrgas i början som sedan sänks genom processen tills bara argon injiceras. Tidigare studier har visat att kolfärskningen är en funktion av konverterns ålder där ju äldre en konverter är desto snabbare går kolfärskning. Enligt studierna har det visats att 8-10% mindre syrgas eller användning av reducerings medel kan uppnås i en gammal konverter vilket har väckt ett intresse för vidare studier. I detta arbete har en av två metoder prövats för att undersöka om man kan applicera det som sker i en gammal konverter till en ny. En numerisk modell av en nerskalad AOD-konverter har utvecklats och validerats mot en vattenmodell då konvertern vinklas. En 75-tons konverter nerskalades till en vattenmodell där vinklarna 0, 5.5 och 14° studerades med fokus på blandningstid och penetrations djup. Vattenmodellen gjordes om till en numerisk modell som använde Euler-Euler metoden i ANSYS Fluent. Modellerna visade likheter gällande penetrationsdjup, flödes struktur och blandnings tid men kräver en del justeringar innan en uppskalning samt koppling till termodynamisk modellering kan ske.
7
Pereira, Alex Lopes. "Accurate abandoned object detection (AOD) in surveillance video." Instituto Tecnológico de Aeronáutica, 2015. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=3230.
Full textAbstract:
The aim of the present research is to investigate the problem known as Abandoned Object Detection (AOD) in surveillance videos, where stationary objects must be classified as either abandoned or removed. We found four categories of methods to solve the AOD problem, namely, region growing, edge detection, color comparison and image inpainting and investigated all of them. We found the major drawback of each category, from which we derived guidelines that oriented the development of three novel methods. Among these three methods, the proposed method (based on edge detection) measures the ratio of a blob boundary that is covered by edges in the reference image. This method achieved convincing results on 66 test scenarios compared to results of most recent works in the literature, equaling or surpassing these results. Furthermore, we proposed a frame window scheme to combine the information from several frames about a given object in order to provide a robust classification. The experiments show our method achieved and surpassed the state-of-the-art results.
8
Larsson, Jesper. "Acid neutralization using steel slags : Adsorption of fluorides in solutions using AOD slags." Thesis, KTH, Materialvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171235.
Full textAbstract:
Surface treatment processes of stainless steel, such as pickling, produces acidic waste water consisting of Na⁺, Cl⁻, F⁻, NO⁻3, SO42-, PO43-, Fe3+, Cr6+ and Ni2+. At Sandvik ABs steel works in Sandviken, this waste water is treated and neutralized using slaked lime before being released into the lake Storsjön. The aim of this report was to make a literary review of previous work in using slag as a neutralizing agent for acidic waste water. Furthermore, to see if it’s possible to replace some or all of the slaked lime in the neutralization process with slag and to study what slag that might be suitable to use. Since the waste water contains HF acid, the focus of this report was on different materials used for fluoride adsorptions. The literary study showed that the fluoride adsorption process with BOF slag, quick lime and magnesium oxide as adsorbents were endothermic. Therefore, it benefitted from an increased temperature. Furthermore, the literature study showed that many materials follow a pseudo-second-order kinetic model as well as a Langmuir or Freundlich isotherm for a fluoride adsorption. A previous experiment showed that a mixture of BF slag and slaked lime had the best HF acid neutralization among the tested materials. A fluoride adsorption experiment was made at different temperatures (25 – 55 °C) by using a slag from an aluminium reduced steel melt and a slag from a silicon reduced steel melt from the AOD converter in Sandviken. The silicon reduced steel melt slag showed an increase of fluorides in the solution, due to the presence of calcium fluoride in the slag. This was observed for all temperatures. The aluminium reduced steel melt slag also increased the fluoride content in the solution at 25 and 30 °C. At higher temperatures the fluoride content in the solution decreased with 93.6 to 94.9 %. Na⁺, Cl⁻, F⁻, NO⁻3, SO42-, PO43-, Fe3+, Cr6+, and Ni2+
9
Bodén, Birgitta. "MAS-sten som ett möjligt material för att minska föroreningarna från deponin i Karlslund : Undersökning av nya tillämpningsområden för slagg från stålindustrin." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209601.
Full textAbstract:
Till följd av den hårda utbyggnaden av vårt samhälle åtgår en stor mängd naturresurser. Samtidigt som samhället utveckas sätts allt högre krav på att det ska hushållas med naturresurser, inte minst genom införandet av miljömålet en ”God bebyggd miljö”. Enligt detta miljömål ska användningen av såväl mark som naturresurser ske på ett så hållbart sätt som möjligt. Samtidigt med detta skapar den svenska stålindustrin över en miljon ton slagg årligen, varav en stor del deponeras. Då deponeringen är kostsam pågår i dagsläget många försök att finna användningsområden för slagg så att deponeringskostanden ska undvikas. Bland annat har slagg i vissa fall visats kunna ersätta naturmaterial i formav sten, grus och sand vid till exempel vägbyggen och deponitäckningar. Slagg har i försök även visat på en vattenrenande förmåga då föroreningar fastläggs på slaggen.Detta har lett till försök med att använda slagg som filtermaterial i reaktiva filter där sand traditionellt sett ofta används. Denna studie avsåg att undersöka om slagg från Avesta Jernverk fungerar att använda i reaktiva filter för att rena vatten som är förorenade med till exempel tungmetaller och fosfor. Detta gjordes genom att skaka tre olika slagger som produceras i Avesta med ett lakvatten från en kommunal deponi med behov att renas från bland annat fluor, fosfor, kadmium, klorider, nickel och zink. I försöken användes en EAF-slagg och två AOD-slagger. För att undersöka om upptaget av föroreningar påverkades av om slaggen hade nya ytor användes både nykrossad slagg och slagg som varit placerade utomhus under 71 dagar. Resultaten visade att slaggerna som bildas vid Avesta Jernverk har en vattenrenandeförmåga och att samtliga av de testade slaggerna sorberade aluminium, fosfor och zink. Utöver dessa ämnen sorberade flera av slaggerna även arsenik, fluor, koppar och magnesium. Resultatet visade också på ett tidsberoende hos sorptionen, då mer föroreningar togs upp om slagg och lakvatten skakades i fem dygn jämfört med om skaktiden var femton minuter eller fyra timmar. Det gick dock inte att avgöra om slagg med nygjorda ytor sorberade bättre än slaggen som stått utomhus. Beräkningar utfördes och visade att ett slaggfilter dimensionsmässigt skulle vara möjligt att bygga och att en kornstorlek som sand skulle behövas för att få rätt uppehållstid.<br>As a result of the harsh exploitation and development of our society, a large amount of natural resources are needed. While the society develops it becomes more and more important to economise natural resources. This is also stated as an environmental objective, called "A good built environment" by the Swedish government. According to this environmental objective, the use of both land and natural resources should be undertaken in the most sustainable way possible. At the same time the Swedish steel industry produces over one million tonnes of slag annually, which is mostly deposited. Slag is a byproduct from the steel manufacturing process. When disposal is costly, many attempts to find usage for slag are done instead. For instance, in some cases it has been as replacement for natural resources as stone, gravel and sand in road constructions and landfill covers. Slag has also been shown to have a water-purifying capacity since contamination can be sorbed by the slag. This has led to attempts to use slag as filter material in reactive filters where sand traditionally is widely used. This study aimed to investigate whether slag from Avesta Works could be used in reactivefilters to purify water that is contaminated with heavy metals and phosphorus. This was done by shaking a number of slags produced in Avesta with leachate water from amunicipal landfill, Karlslund. The leachate water needs to be purified from i.a. fluorine, phosphorus, cadmium, chloride, nickel and zinc. In the experiments an EAF slag and two AOD slags were used. To investigate if the sorption of contamination in the leachate water was affected by the age of the particle surfaces, both slags with freshly made and aged surfaces were tested. The aging of the slags was created by placing the slags outdoor for 71 days. The results showed that the slags formed at Avesta Works has a water-purifying ability and that all of the tested slags sorbed aluminum, phosphorus and zinc. Beside these substances, some of the slags also sorbed arsenic, fluorine, copper and magnesium. Theresults also showed a time-dependence of the sorption: More contaminations were sorbed after reacting slag and leachate water for five days compared with fifteen minutes or four hours. It was not possible to determine if the slags with fresh surfaces sorbed better than the slags with aged surfaces. Calculations showed that a filter containing slag should be possible to build dimensionally and that the grain size of sand would be needed to get the required retention time.
10
Adegoloye, Obafèmi Gildas Franck. "Valorisation des laitiers issus de l'élaboration d'aciers inoxydables dans le béton." Thesis, Cergy-Pontoise, 2014. http://www.theses.fr/2014CERG0719/document.
Full textAbstract:
Le laitier EAF inox et le laitier AOD sont les deux principaux laitiers issus de l'élaboration des aciers inoxydables. Aujourd'hui ces laitiers ne sont valorisés qu'en construction routière. Cette utilisation ne permet pas d'assurer une valorisation complète et pérenne de ces laitiers dont une large part reste stockée. Compte tenu des propriétés physiques des laitiers EAF inox et AOD solidifié par stabilisation, leur utilisation comme granulats dans le béton peut être intéressante. L'objectif de cette thèse est d'étudier la faisabilité de cette voie de valorisation. Ces travaux sont réalisés en deux parties.Premièrement les propriétés physico-chimiques et mécaniques des granulats de laitiers EAF inox et AOD stabilisé sont déterminées. La composition minéralogique complète de ces granulats de laitiers issus de l'élaboration d'aciers inoxydables est aussi analysée afin de rechercher la présence éventuelle de minéraux instables et incompatibles à leur utilisation dans le béton. Compte tenue de la fluorescence sous rayons ultra-violet (UV) des laitiers, une nouvelle approche qui associe les UV et les analyses minéralogiques courantes (DRX, MEB, EDS) est développée dans cette étude. Cette étape de caractérisation des granulats des laitiers étudiés fait de ce mémoire de thèse le premier rapport sur la caractérisation physique, chimique et minéralogique des granulats de laitier AOD stabilisé. La deuxième étape de cette étude consiste à réaliser des bétons en substituant, dans des proportions variées, des granulats naturels silico-calcaires d'un béton de référence par des granulats de laitiers EAF inox et AOD stabilisé. Les propriétés physiques et mécaniques de ces bétons à matrice ordinaires et à hautes performances sont évaluées. Une étude de durabilité de ces bétons est aussi effectuée à travers le suivi des propriétés mécaniques des bétons sur 365 jours, l'analyse d'indicateurs de durabilité et la réalisation d'essais de gonflement. Enfin des observations MEB sont faites sont faites les échantillons de béton âgés de 365 jours pour observer et analyser le réseau de fissures à l'interface granulat – matrice cimentaire. Les résultats montrent des propriétés adaptées à une utilisation structurelle, avec une légère amélioration des caractéristiques mécaniques et des propriétés de durabilité acceptables pour les bétons de granulats de laitiers EAF inox et AOD stabilisé<br>Electric Arc Furnace (EAF) slag and Argon Oxygen Decarburization (AOD) slag are the two principal slags resulted from stainless steel manufacture. Unlike blast furnace slag, a significant part of these steel slags is not valued and has to be treated as waste. Stainless steel slags are nowadays only used as aggregates in road construction and their future valorisation in concrete for building could be interesting. To our knowledge, that possibility has not yet been studied in the literature. The objective of this work is to study the possibility of using slags from stainless steel process as aggregates in concrete. Moreover, this is the first report on mineral composition and physical properties of stabilized AOD slags from stainless steel process.In this study, physicochemical and mechanical properties of EAF slag and stabilised AOD slag aggregates are firstly determined. Mineralogical composition of these stainless steel slag aggregates is also analysed to verify if they contain mineral phases likely to show expansion reactions. An original method using short and long UV lights was developed for studying the mineralogical composition of slag. Secondly, the natural aggregates of reference concretes are substituted, in different proportions, by stainless steel slag aggregates and several physical and mechanical properties are measured on concrete samples. The evolution of concrete mechanical properties has been followed over the time up to 365 days. Similarly, durability tests and swelling tests are made on concrete samples to assess the impact of EAF and AOD slag aggregates. SEM observations of crack network at the paste-aggregate interface and in concrete samples were carried out. The results show adequate structural properties, with a slight improvement of the mechanical properties for concretes made of stainless steel slag aggregates. The durability and expansion characteristics of these concretes are sufficient for construction use
11
Visuri, V. V. (Ville-Valtteri). "Mathematical modelling of chemical kinetics and rate phenomena in the AOD Process." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526216713.
Full textAbstract:
Abstract Argon-oxygen decarburisation (AOD) is the most common unit process for refining stainless steel. The AOD process consists of multiple stages, in which the rate of processing is determined by complex reaction mechanisms. The main objective of this work was to study the chemical rate phenomena in selected process stages. For this purpose, an extensive literature review was conducted to clarify the main assumptions of the existing reaction models. Based on the literature review, a new categorisation of the models was proposed. In addition, a literature review was conducted to identify the main phenomena that affect the reaction kinetics in the AOD process. In this work, based on the law of mass action, a novel kinetic approach and its application for modelling of parallel mass transfer controlled reactions were studied. The developed approach enables the simultaneous solution of the chemical equilibrium and mass transfer rate which controls it. A simplified reaction model was employed for studying the effect of mass transfer rates and residual affinity on the constrained equilibrium at the reaction interface. An earlier-proposed AOD model was extended with two phenomenon-based sub-models. The top-blowing model is based on the assumption that reactions take place simultaneously at the surface of the cavity formed by the momentum of the gas jet and on the surface of the metal droplets caused by the shear force of the gas jet. The reduction model describes the reactions during the reduction stage of the AOD process by assuming that all reactions take place between the metal bath and emulsified slag droplets. The results obtained with the models were in good agreement with the measurement data collected from a steel plant. Owing to their phenomenon-based structure, the developed models are well-suited for the analysis of both existing and new production practices<br>Tiivistelmä Argon-happimellotus (AOD) on yleisin ruostumattoman teräksen valmistamiseen käytettävä yksikköprosessi. AOD-prosessi koostuu useista vaiheista, joissa prosessointinopeutta määrittävät monimutkaiset reaktiomekanismit. Tutkimuksen päätavoitteena oli tutkia kemiallisia nopeusilmiöitä valituissa prosessivaiheissa. Tähän liittyen tehtiin kattava kirjallisuuskatsaus, jonka tavoitteena oli tunnistaa olemassa olevien reaktiomallien pääoletukset. Kirjallisuuskatsauksen pohjalta esitettiin uusi mallien kategorisointi. Lisäksi tehtiin kirjallisuuskatsaus, jonka tavoitteena oli tunnistaa tärkeimmät reaktiokinetiikkaan vaikuttavat ilmiöt AOD-prosessissa. Tässä työssä tutkittiin uudenlaista massavaikutuksen lakiin perustuvaa lähestymistapaa sekä sen soveltamista rinnakkaisten aineensiirron rajoittamien reaktioiden mallinnukseen. Kehitetty lähestymistapa mahdollistaa kemiallisen tasapainotilan sekä sitä rajoittavan aineensiirron samanaikaisen ratkaisun. Aineensiirtonopeuksien ja jäännösaffiniteetin vaikutusta reaktiopinnalla vallitsevaan rajoitettuun tasapainotilaan tutkittiin käyttämällä yksinkertaistettua reaktiomallia. Aiemmin kehitettyä AOD-mallia laajennettiin kahdella ilmiöpohjaisella alimallilla. Lanssipuhallusmalli perustuu oletukseen, että reaktiot tapahtuvat samanaikaisesti kaasusuihkun liikemäärän muodostaman tunkeuman ja kaasusuihkun leikkausvoiman aiheuttamien metallipisaroiden pinnalla. Pelkistysmalli kuvaa AOD-prosessin pelkistysvaiheen aikana tapahtuvia reaktioita olettaen, että kaikki reaktiot tapahtuvat terässulan ja emulgoituneiden kuonapisaroiden välillä. Malleilla saadut tulokset vastasivat hyvin terästehtaalta kerättyä mittausaineistoa. Ilmiöpohjaisen rakenteensa ansiosta kehitetyt mallit soveltuvat hyvin sekä olemassa olevien että uusien tuotantopraktiikoiden analysoimiseen
12
Isohookana, E. (Erik). "A physical modelling study of mixing in an AOD converter." Master's thesis, University of Oulu, 2015. http://urn.fi/URN:NBN:fi:oulu-201509041955.
Full textAbstract:
The aim of this thesis was to model mixing in a 150 ton AOD converter with physical water model experiments. The mixing of a tracer at different tuyere blowing rates and injection depths was investigated. Water model experiments were carried out in the laboratory of the Process Metallurgy Group at the University of Oulu. The geometric ratio of the model to the real converter was 1:9. All dimensions of the model corresponded to the ratio except the diameter of the tuyeres. There were 7 tuyeres located in the sidewall, near the bottom of the model. Pressurized air was blown from the tuyeres into the system at volumetric air flow rates of 0.140, 0.350 and 0.560 Nm³/min. Sulfuric acid (98%) was used as a tracer in these water model experiments and the changes of the pH were measured with a pH-meter. Mixing time experiments were executed in three series. Volumetric air flow rates followed the previously mentioned volumes. In addition to this, the injection depths of the tracer were set to be 0.1 m and 0.2 m. The influence of the injected tracer on the pH value of the water bath, was measured with a pH-meter which was connected to a laptop computer. It was therefore possible to calculate the mixing time of the tracer from the collected data. The experiment indicated that increased volumetric air flow rates from the tuyeres significantly expedited mixing. The average mixing times with volumetric air flow rates of 0.140, 0.350 and 0.560 Nm³/min and an injection depth of 0.1 m were 25.2, 12.1 ja 6.72 seconds. With the same volumetric air flow rates, an injection depth of 0.2 m gave different mixing times. The average mixing times with the previously mentioned values were 25.59, 17.76 and 10.56 seconds. Based on the experiments of this thesis, an increased volumetric air flow rate was verified as decreasing the mixing time. On the other hand, increasing the injection depth of a tracer increased the mixing time<br>Tämän diplomityön tarkoituksena oli mallintaa 150 tonnin AOD-konvertterin sekoittumista fysikaalisten vesimallikokeiden avulla. Tutkimuksessa selvitettiin veteen injektoitavan merkkiaineen sekoittumisnopeutta eri suutinpuhalluksen tilavuusvirroilla ja merkkiaineen injektiosyvyyksillä. Laboratoriokokeet suoritettiin Oulun yliopiston Prosessimetallurgian tutkimusryhmän vesimallilla. Mallin geometrinen suhde todelliseen konvertteriin oli 1:9. Mallin kaikki dimensiot vastasivat geometrista suhdetta pois lukien suuttimien halkaisijat. Suuttimien lukumäärä oli 7 ja ne oli sijoitettu vesimallin sivuseinämään pohjan läheisyyteen. Vesimalliin puhallettiin suuttimien kautta paineistettua ilmaa tilavuusvirroilla 0,140, 0,350 ja 0,560 Nm³/min. Merkkiaineena kyseisissä vesimallikokeissa käytettiin rikkihappoa (98 %), jonka sekoittumista veteen mitattiin vesimalliin asennetulla pH-mittarilla. Sekoittumisaikamittaukset suoritettiin kolmessa osiossa, joissa kaikissa pohjapuhalluksen tilavuusvirrat noudattivat edellä mainittuja tilavuusvirtoja. Tämän lisäksi, injektoitavan merkkiaineen injektiosyvyyksinä käytettiin 0,1 ja 0,2 m. Injektoidun merkkiaineen vaikutusta veden pH-arvoon mitattiin tietokoneeseen yhdistetyllä pH-mittarilla, jotta merkkiaineen sekoittumisaika vesimallissa olisi laskettavissa. Sekoittumisaikamittauksista havaittiin, että pohjasuuttimista puhallettavan paineistetun ilman tilavuusvirran kasvattaminen nopeutti sekoittumista huomattavasti. Injektiosyvyyden ollessa 0,1 m keskimääräiset sekoittumisajat 0,140, 0,350 ja 0,560 Nm³/min tilavuusvirroilla olivat 25,2, 12,1 ja 6,72 sekuntia. Samoilla tilavuusvirroilla tehdyt testit merkkiaineen injektiosyvyyden ollessa 0,2 m, tuottivat eri erilaisia sekoittumisaikoja. Sekoittumisen keskimääräiset ajat kyseisillä tilavuusvirroilla ja merkkiaineen 0.2 m injektiosyvyydellä olivat 25,59, 17,76 ja 10,56 sekuntia. Tämän diplomityön sekoittumisaikamittauksien pohjalta todettiin pohjapuhalluksen tilavuusvirran kasvattamisen lyhentävän sekoittumisaikaa kyseisellä vesimallilla. Merkkiaineen injektiosyvyyden kasvattaminen puolestaan kasvatti sekoittumisaikaa
13
Mickelsson, Sandra. "Kartläggning av AOD-konverterns ingångsförhållanden och dess påverkan på färskningstiden." Thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70230.
Full textAbstract:
Sandvik Materials Technology tillverkar varje år cirka 230 000 ton stål varav en stor del är rostfritt stål. För att sänka kolhalten i stålet används en AOD-konverter där en kombination av syrgas och inertgas blåses in stålet för att avlägsna kol som kolmonoxid. Vissa duplexa rostfria stålsorter är trögfärskade vilket lätt leder till att konvertern blir flaskhalsen i stålverket. Syftet med arbetet är att undersöka och kartlägga parametrar som påverkar färskningstiden för trögfärskade duplexa stålsorter. Tiden i konvertern kan variera kraftigt mellan olika charger och det finns därför en ekonomisk drivkraft i att förkorta färskningstiden. Kolfärskningen i AOD-konvertern bygger på drivkraften hos kol att reagera med syre. Genom att använda blåssteg med ökande andel inertgas kan partialtrycket av CO-gas i stålet sänkas vilket gynnar oxidationen av kol. Vid färskning av rostfria stål som innehåller höga halter krom oxideras både kol och krom på grund av hög affinitet för syre. En liten slaggvolym kan anses som gynnsamt för färskningen då en mindre mängd kromspineller kan bindas till slaggen. Parametrarna har undersökts genom statistik från historiska charger samt genom ytterligare provtagningar under färskningsförloppet. De parametrar som undersökts är ståltemperatur, tid i överföringsskänk, mängd justeringar, antal dysor och gasflöde, operatör, stålsammansättning och slaggens inverkan. Det är ett stort antal parametrar som påverkar färskningen och det är svårt att avgöra vilken eller vilka som påverkar mest. Utifrån resultatet kan det ses att de undersökta parametrarna påverkar resultatet på olika sätt; en hög temperatur in i konvertern är gynnsam lika som en kort tid i överföringsskänken och en stålsammansättning nära riktvärdet. Många av parametrarna är dessutom beroende av varandra så som att stålsammansättningen påverkas av justeringarna och temperaturen påverkas av tiden i överföringsskänken. Slaggens inverkan på färskningen studerades utifrån typen och mängden slaggbildare. Resultaten visar att kromspineller bildas i slaggen oberoende av vilken slaggbildare som används. För chargen med slaggbildare 1 var det tydligt att det fanns fri kalciumoxid i slaggen vilket tyder på att slaggen är mättad på kalciumoxid. En mättad slagg kan leda till bildandet av en större mängd spineller vilket kan leda till en längre färskningstid. När slaggbildartillsatsen förändrades och tillsattes under steg 2 visar resultatet att 5/10 charger når en kolhalt under riktvärdet vid prov 54. Slutsatser som kan dras är att det är viktigt att fokusera på de parametrar som har en stor påverkan på färskningstiden men samtidigt är möjliga att påverka. Det kan vara att använda fler dysor och på så sätt öka gasflödet, minska slaggvolymen eller undvika att stålet förvaras långa tider i överföringsskänken.
14
Gray, Calonie Marie Kelli. "An Investigation of the Relationship Between Maltreatment and Alcohol and Other Drug (AOD) Use Among African-American and Hispanic Adolescent Girls." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/204.
Full textAbstract:
Maltreatment experienced in childhood or adolescence is a known risk factor for later problem alcohol and/or other drug (AOD) use (Bailey & McCloskey, 2005; Shin, Edwards, Heeren, 2009). A growing body of empirical work has found significant associations between adolescent girls’ AOD use and maltreatment experiences. However, questions remain as to how this relation unfolds with African-American and Hispanic adolescent girls. Guided by four relational models that have been proposed in the literature, this study examined the links between maltreatment, trauma symptoms, and alcohol and/or other drug (AOD) problems in a sample of 170 African-American and Hispanic adolescent girls who were participants in a school-based AOD use intervention. Results of this study revealed that maltreatment experiences (physical and emotional abuse) were positively related to trauma symptoms, which were positively related to AOD problem severity, alcohol abuse, alcohol dependency, drug abuse, and drug dependency. Perceived discrimination moderated this relation between sexual abuse and trauma symptoms, such that more perceived discrimination resulted in a stronger effect of sexual abuse on trauma symptoms. Ethnic identity moderated the relation between sexual abuse and AOD problem severity, such that ethnic identity demonstrated protective properties in the relation between sexual abuse and AOD problem severity. My research adds to extant knowledge on the relation between maltreatment and AOD use in adolescent girls and suggests the importance of developing interventions targeting maltreatment and AOD use concurrently.
15
Eriksson, Selin William. "Study of antenna arrays for direction finding." Thesis, Umeå universitet, Institutionen för fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-187309.
Full textAbstract:
The new Bluetooth standard (Bluetooth 5.1) contains direction finding specifications. Specifications for received signal strength indicator(RSSI) using measures of signal strength in order to give a sense of how far away an object is has been present in earlier versions. It will now be accompanied with the possibility of angle of arrival estimation(AoA). AoA estimation in Bluetooth utilizes antenna arrays. Antenna arrays are formations of many individual antenna elements working together. The difference between the measured data at each antenna is dependent on the orientation and position of the antenna elements as well as on phase of an incoming electromagnetic signal. By looking at the phase shifts between the antenna elements in an antenna array it is possible to find an estimation of the direction of where the incoming signal is coming from. The goal of this thesis is to investigate if the NicheTM antenna(concept developed by Proant AB) is applicable for AoA estimation. In the project we have simulated the different characteristics of the Niche antenna and done extensive simulations of different types of configurations of an Niche antenna array. The commercial electromagnetics simulator CST MW studio suite has been used for simulations. A formation that works well with regards to stability and mutual coupling has been found. The simulated results have also been confirmed by measurements on a mechanically constructed antenna array. Measurements have been carried out in an anechoic chamber. We have done full radiation pattern measurements of the antenna array. The antenna array that we have created can estimate the angle of arrival of an incoming signal with an accuracy of 2.7o with a certainty of one standard deviation. For increased accuracy in the AoA estimation a MATLAB code utilizing the MUSIC(MUltiple SIgnal Classification) algorithm with our variant of the steering vector has been written.
16
Marin, Humberto. "Modelamento matemático do refino do aço inoxidável em conversores AOD-L." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/BUOS-8DHFBC.
Full textAbstract:
In the present work was presented a study about the development and the application of a multiphase and multicomponent mathematical model for the decarburisation of stainless steels. The developed model takes into account three possible interfaces of reaction (metal-gas, metal-oxide and oxide-gas) and considers the main components involved in the process (C, Cr, Fe, Ni, Mn, Si, Al, O). To model the process it was assumed that the oxygen injected by the bottom in the converter reacts with the metal in the region of the tuyeres, forming metallic oxides that rise with the gas bubbles. During the rising of the bubbles, the oxides are dragged and reduced, forming CO and CO2 due to the reaction with the carbon dissolved in the bath. This causes a carbon flow towards the gaseous phase (bubbles) and, consequently, decarburisation. Themodel was adjusted to the Acesita S.A. 80 tonnes AOD-L converter process conditions. The converter works with charge from an electric arc furnace and dephosforized hot metal. The simulation results showed that the model reproduces well the main process variations (bath temperature, bath chemical composition and oxygen dilution by inertgas), corresponding to the operational practice and bibliographic reports. The results of the simulations were compared to industrial data, of austenitic ACE P304A steel grade and of ferritic ACE P430A steel grade heats, giving a good prevision of carbon content and temperature as function of the process time<br>Neste trabalho foi apresentado um estudo sobre o desenvolvimento e a aplicação de um modelo matemático multifásico e multicomponente para a descarburação de aços inoxidáveis. O modelo desenvolvido trata, de maneira explícita, as três interfaces possíveis de reação (metal-gás, metal-óxido e óxido-gás) e considera os principais componentes envolvidos no processo (C, Cr, Fe, Ni, Mn, Si, Al, O). Para o modelamento do processo foi considerado que o oxigênio injetado por baixo no conversor reage com o metal na região das ventaneiras, formando óxidos metálicos que sobem junto com as bolhas de gás. Durante a subida do gás, os óxidos são arrastados e reduzidos, ocorrendo formação de CO e CO2 devido à reação com o carbono dissolvido no banho, causando um fluxo de carbono para a fase gasosa (bolhas) e conseqüente descarburação do banho. O modelo foi ajustado para ascondições de processo do conversor AOD-L de 80 toneladas da Acesita S.A., que trabalha com carga proveniente do forno elétrico a arco e gusa desfosforado. Os resultados das simulações mostraram que o modelo é capaz de reproduzir de maneira satisfatória às principais variações de processo (temperatura do banho, composição química do banho e diluição do oxigênio injetado com gás inerte), correspondendo aoque é conhecido da prática operacional e registros bibliográficos. Resultados obtidos com o modelo foram comparados com resultados industriais, de corridas do aço austenítico, ACE P304A e do aço ferrítico ACE P430A, fornecendo uma boa precisão na previsão do teor de carbono e temperatura do banho em função do tempo de processo.
17
Khaghani, Ali, and Ali Khaghani. "Spatiotemporal Analysis of Aerosol Over A Major Salt Lake Region: Case Study of Lake Urmia In Iran." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/624115.
Full textAbstract:
Lake Urmia (LU), which once had been the second largest hypersaline lake in the world, and greatest in the Middle East, has undergone severe environmental changes during recent years that have led to widespread desiccation. These changes have converted the lakebed into a significant Aeolian mineral source, which promotes aerosol plumes that can seriously impact downwind regions. A question remains as to how significant emissions are from LU as compared to others impacting the West and East Azarbaijan provinces encompassing LU. This study uses daily Aerosol Optical Depth (AOD) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) between 2001 and 2015 to show that AOD levels are significantly larger in the latter half of the study period (2008-2015) with AOD values in the West consistently being lower but approaching those of the East with time owing to a combination of increasing emissions from the West province and neighboring areas. While the interannual AOD profile over Azarbaijan resembles that of Iraq owing to transported dust, signatures of the local impact of increasing emissions is evident over the 15-year time period, especially in the months outside of the peak dust season (January, February and October) and on the immediate periphery of LU. Consequently, the spatial profile of AOD over Azarbaijan is not uniform but with distinct hot spot. The onset of the spring AOD ramp-up over Azarbaijan is shown to have started earlier (in February) when comparing 2009-2015 versus earlier years. Correlative analysis confirms that AOD is related to factors promoting dust emissions but also reveals that smoke contributes to AOD over Azarbaijan during the summer months.
18
Englund, Hanna, and Henrietta Isaksson. "Regulation of Nitrogen Content in High Alloyed Stainless Steels during the AOD Process." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254419.
Full textAbstract:
As a final step in the argon oxygen decarburisation (AOD) process, argon- and nitrogen gas is blown through the melt. To regulate the nitrogen content in the steel melt during this step a reliable model is needed. With data from 31 heats of the duplex stainless steel SAF2507 collected at Sandvik Materials Technology (SMT), different models are investigated. This is done by looking at the partial pressure of the nitrogen gas and the nitrogen content achieved during each heat. By calculating the nitrogen solubility in the steel melt with different models and then using Sieverts’s law, a partial pressure for the nitrogen gas is obtained for each heat and compared with the data. With adjustments done for a model obtained from J. Kijac et al., more reliable results are attained than by the model used today at SMT. It should be kept in mind that this model is based on the theory with diluted solution and is therefore not optimal for high alloyed steels, and it is suggested to develop a model from a software based on real solution such as Thermo-Calc.<br>I slutskedet av AOD-processen blåses argon- och kvävgas genom stålsmältan. En pålitlig modell behövs för att reglera kvävehalten i stålsmältan under det här steget. Olika modeller undersöks med data från 31 charger av det duplexa rostfria stålet SAF2507 samlad från Sandvik Materials Technology (SMT). Undersökningen sker genom att titta på partialtrycket av kvävgasen och kvävehalten som uppnåddes för varje charge. Genom att beräkna kvävelösligheten i stålsmältan med olika modeller och sedan använda Sieverts lag, kan ett partialtryck för kvävgas räknas ut för varje charge och jämföras med datan. Mer exakta resultat är uppnådda med en justerad modell hämtad från J. Kijac et al. jämfört med den modell använd på SMT idag. Att ha i åtanke är att denna modell är baserad på teori med antagande om utspädd lösning, vilket inte är optimalt för höglegerade stål och ett förslag är att utveckla en modell med hjälp av ett mjukvaruprogram som baseras på äkta lösning såsom Thermo-Calc.
19
Laxén, Jonas. "Possibilities and limitations of exhaust gas analysis for expanded use in control of an AOD-converter." Thesis, KTH, Tillämpad processmetallurgi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-103256.
Full textAbstract:
The main purpose of the AOD-converter is to lower the carbon content in stainless steel production. The carbon content can be estimated by static theoretical models. It can also be estimated through dynamic models based on analysis of the exhaust gases from the converter. This master thesis is a study on an extended use of exhaust gas analysis data on the AOD-converter at Outokumpu’s stainless steel plant in Avesta, Sweden. There are two main methods of predicting the carbon content based on exhaust gas analysis, mass balance and a linear regression between decarburization rate and carbon content. This master thesis mainly focuses on the development of the linear regression model for steel grades ASTM 304L, 316L, S32101 and S32205 for the last step of the decarburization, as well as ASTM S32205 and S30815 for the second last step of the decarburization. The results showed that the linear regression model can predict the carbon content at the last step of decarburization with a standard deviation between 0,00626 %C and 0,0109 %C for the different steel grades. An equation for carbon prediction dependent on the steel composition was also developed in the master thesis, making it theoretically possible to use for all steel grades, it has however not yet been tested on other steel grades. The CRE measured from the exhaust gases was also studied to find out if it is possibleto use as basis for step changes during the decarburization, but the resultswere inconclusive.<br>Huvudsyftet med AOD-konvertern är att sänka kolhalten i produktionen av rostfritt stål. Kolhalten kan uppskattas av statiska teoretiska modeller. Den kan också uppskattas av dynamiska modeller baserade på analys av avgaserna från konvertern. Det här examensarbetet handlar om utvidgning av användandet av avgasanalysdata på AOD-konvertern på Outokumpus stålverk i Avesta, Sverige. Det finns i huvudsak två metoder för att bestämma kolhalten med hjälp av avgasanalys, massbalans och en linjär regression mellan kolfärskningshastigheten och kolhalten. Det här examensarbetet fokuserar i huvudsak på utvecklingen av den linjära modellen för stålsorterna ASTM 304L, 316L, S32101 och S32205 för sista steget i kolfärskningen. Samt stålsorterna ASTM S32205 och S30815 för näst sista steget i kolfärskningen. Resultaten visade att den linjära modellen kunde uppskatta kolhalten i sista steget av kolfärskningen med en standardavvikelse mellan 0,00626 %C och 0,0109 %C för de fyra olika stålsorterna. En ekvation som anger sambandet mellan sammansättningen på stålet under kolfärskningen och ekvationen för den linjära regressionen togs också fram i examensarbetet. Teoretiskt kan ekvationen användas för alla stålsorter men den har inte än blivit testad på andra stålsorter. CRE uppmätt med hjälp av avgasanalys undersöktes också för att ta reda på om CRE kan användas för att bestämma när stegbytena ska ske, det gick dock inte att utgöra från resultaten.
20
Reiss, Elayne. "EVALUATION OF AN ONLINE ALCOHOL EDUCATION PROGRAM FOR FIRST-TIME-IN-COLLEGE STUDENTS." Doctoral diss., University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3027.
Full textAbstract:
Alcohol use among college students has maintained its place as a major issue in American higher education since its inception. Although dangerous drinking has always proliferated among college students, institutions have only provided alcohol and other drug (AOD) education and interventions encouraging students to adapt less harmful habits for a much shorter period of time. During this relatively short history of postsecondary alcohol interventions, colleges and universities have shifted away from abstinence-only, education-based methods. Instead, institutions have begun to adapt cognitive behavior-centric, motivational enhancement-based strategies emphasizing harm reduction through the use of protective behaviors. In order to reach a greater number of students, alcohol intervention programs have been developed combining the harm reduction ideology with internet-based dispersion at a population level. This research study addressed the behavioral changes that occurred among an entire class of first-time-in-college freshmen at a large public university before and after mandatory participation in AlcoholEdu for College, an online, population-level, harm reduction-based alcohol intervention. The study expanded upon previous evaluations of the program, which addressed program efficacy among the population as a whole but did not further explore differences in effect upon students engaging in different levels of drinking. Other demographic factors, such as gender, ethnicity, family history of alcohol issues, and age of first consumption, were also taken into account. Pre-test surveys taken by students prior to the intervention at the beginning of the academic year were matched to follow-up surveys taken four to six weeks after program completion, providing the necessary data for conducting a quantitative study. The specific areas of interest within the study included (a) willingness to complete the program in a timely and complete fashion, (b) levels of consumption, (c) use of protective behavioral strategies (PBS), and (d) incurrence of negative alcohol-related consequences. A combination of analytical procedures was utilized, including descriptive statistics, chi-square tests for independence, exploratory factor analysis, repeated measures ANCOVA, and nonparametric inferential tests. Results were described within the framework of social cognitive theory (Bandura, 2004) as well as the CIPP program evaluation framework (Stufflebeam & Shinkfield, 2007). The analysis uncovered that three major factors determined willingness to complete the mandatory program in a timely and complete fashion: gender, age of first alcohol consumption, and drinker group. Specifically, students who were male, started drinking prior to high school, or were identified as heavy episodic drinkers were less likely than peers to complete all portions of the AlcoholEdu program. Both moderate and heavy episodic drinkers reduced their levels of consumption between pre-test and follow-up. A large percentage of abstaining students maintained this status later in the semester. Light and moderate drinkers either maintained or slightly reduced their use of PBS, while heavy episodic drinkers showed increases in use of most types of PBS over time. All students indicated low levels of incurrence of negative consequences in both the pre-test and follow-up periods. However, while students experienced an increased number of most of these consequences between the pre-test and follow-up surveys, heavy drinkers cited a decreased rate of drinking and driving-related consequences as of the follow-up. Throughout all of the analyses, important controlling factors included gender, ethnicity, and age of first alcohol consumption. The results of this study can guide future development and refinement of the AlcoholEdu program, as well as provide higher education administrators and AOD education program staff with additional baseline knowledge of the change process first-time-in-college freshmen undergo when engaged in the program.<br>Ed.D.<br>Department of Educational Research, Technology and Leadership<br>Education<br>Educational Leadership EdD
21
Elmroth, Edvin. "Adsorption of Zn, Cd, V, Ba, Cu, Mo, Ni, Cr, Li and Pb to silicon and aluminium reduced AOD-slag." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-68989.
Full textAbstract:
During production of steel, slag is formed as a by-product. The process of steelmaking involves usage of additives such as chromium or vanadium as reactants to optimize and produce high quality steel. Vast amounts of slag are formed and there is a continuous search for applications that can make good use of the slag. Currently the use of slag in cleaning of metal polluted waters is researched and promising results has been found for many different types of slags. In this work two different AOD-slags has been used as sorbents for some selected elements (Zn, V, Cr, Mo, Pb, Li, Cd, Ba, Cu, Ni). The main difference between the two slags is the reducing agent that has been used, aluminium and silicon. This results in slags with different adsorption properties. The aluminium reduced slag show tendency for better adsorption capacities in general for the tested elements (Zn, V, Cr, Mo, Pb, Li, Cd, Ba, Cu, Ni), with a few exceptions. The buffering capacity of the materials were high, shown by the fact that final pH reached nearly 11.5 independent of the start pH (varied between 2 and 8). The adsorption process was rather quick and 24 minutes contact time was in most cases sufficient to reach equilibrium. For several of the elements e.g. Lithium, the maximum capacity of the slags was not reached even though a load of 3,07 mg Lithium was added per gram of slag.
22
Sama, Aravind Reddy. "AOD²V : Ad Hoc On Demand and Delay Constrained Distance Vector Routing for mobile sensor/actor networks /." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1619624051&sid=12&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Full text
23
Escribano, Alisio Jerónimo José. "Capa límite, reflectancia y espesor óptico de aerosoles sobre Santiago." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/112079.
Full textAbstract:
Magíster en Meteorología y Climatología<br>Ingeniero Civil Matemático<br>Se ha sugerido que el espesor óptico de aerosoles (AOD) derivado a partir de sensores a bordo de satélites puede ser un complemento a las mediciones superficiales de concentración de aerosoles en la capa límite. Se explora si esto es aplicable en el caso de Santiago de Chile, comparando el producto de AOD derivado de la señal satelital del instrumento MODerate resolution Imaging Spectroradiometer (MODIS) con diez años de mediciones in situ de concentraciones de material particulado parcialmente respirable (PM10) y totalmente respirable (PM2.5). Para ello, se desarrolla y aplica un modelo numérico simple de AOD en base a mediciones de concentración de material particulado en superficie, altura de capa límite y propiedades de aerosoles obtenidas de la literatura junto con la información disponible de estos parámetros para la ciudad de Santiago. El modelo captura la variabilidad estacional del AOD cuando es comparado con las observaciones obtenidas con un fotómetro solar de la red AErosol RObotic NETwork (AERONET) y también captura la variabilidad diurna en el caso de una campaña de un día. La variabilidad estacional opuesta entre la altura de la capa límite y la concentración de material particulado en superficie son las principales responsables de una estacionalidad débil del AOD simulado.
Se observa una marcada estacionalidad del AOD satelital opuesta a la estacionalidad de la concentración de material particulado en superficie. Por otro lado y debido a la poca cantidad de mediciones simultáneas de AERONET y MODIS, se incluyen las simulaciones en la comparación de AOD. Se observa una considerable diferencia entre el comportamiento estacional del AOD simulado y el derivado de MODIS. En trabajos anteriores se sugiere que la presencia de nubes cirrus es la causa de la estacionalidad opuesta. En este estudio se deduce que aparentemente esta estacionalidad no se debe a la presencia de nubes cirrus.
Con el uso de un modelo de reflectancia de superficie y sus parámetros derivados de MODIS, se propone que la diferencia entre la variación estacional del AOD de MODIS y aquella simulada se explica en gran parte por estimaciones inadecuadas de la reflectancia de la superficie y en menor grado por la selección inadecuada de propiedades ópticas y de proporción de fracción fina del aerosol en el algoritmo de MODIS. Se muestra que esta proposición se sustenta observacionalmente en el caso de Buenos Aires, donde se compara el AOD de MODIS con el observado por AERONET.
24
Euphrasie-Clotilde, Lovely. "Climatologie du transport des aérosols désertiques au-dessus de l'Atlantique vers la région Caraïbe." Thesis, Antilles, 2018. http://www.theses.fr/2018ANTI0260/document.
Full textAbstract:
La région Caraïbe est régulièrement survolée par des masses d'air chargées en poussières désertiquesd'origines saharienne et sub-saharienne. Pour quatre îles de l'arc antillais : Porto Rico, Guadeloupe, Martinique etBarbade; nous avons évalué l'origine de la pollution particulaire et son impact sur la qualité de l'air, en effectuant uneétude statistique des évènements de poussière qui s'appuie sur les réseaux de mesure de qualité de l'air implantés surchacune des îles, sur le réseau international de mesures photométriques AERONET et sur les données deradiosondages réalisés localement. La première étape de notre travail, a visé à définir ce que l'on pouvait qualifier« d'épisode de poussières désertiques» dans notre région en établissant des critères utilisant le jeu de données dontnous disposions. Deuxièmement, nous avons réalisé une étude climatologique des évènements poussiéreux dans laCaraïbe au cours de la dernière décennie (2006-2016). Le troisième axe de la thèse repose sur la caractérisation de lataille des particules afin de mettre en relief les effets du transport à longue distance. Nous avons clôturé notre étudepar la description de la structure verticale de l'atmosphère de la zone tropicale en situation de « brumes de poussièredésertique » afin d'observer les effets thermodynamiques des aérosols minéraux sur la couche atmosphérique. Ladéfinition des évènements de brumes désertique que nous avons adoptée nous a permis de prendre en considérationune grande partie des évènements poussiéreux affectant l'arc antillais, ce qui nous a amené à mieux cerner le cycle detranspon des poussièl'es désertiques au terme d'une étude basée sur onze années de données<br>The Caribbean region is regularly flown over by desert dust air masses (Saharan Air Layer) corne fromSaharan and sub-Saharan area. For four islands of the West Indies arc: Puerto Rico, Guadeloupe, Martinique andBarbados; we assessed the origin of polluting particles and their impact on air quality, by performing a statistical andclimatological study of desert dust events. We therefore based on the air quality measurement networks, theinternational AEronet RObotic NETwork (AERONET) photometric measurements installed on each of these islands.And finally, this study builds on sounding data produced locally.The first step in our work was to define and describe an "desert dust episode" in the tropical region. Thus, we studiedthe relationship of correlation between Aerosols Optical Depth (AOD), Angstrom Exponent (AE, characterizing theparticle size) and Particulate Matter 10 microns or Jess in diameter (PM10 data). On the other hand, the radiativeproperties (Single Scattering Albedo, refractive indexes) have been used to highlight sea sait contribution (coarseparticle just as dust particle) that significantly influences PM10 measurement due to the geographical context ofCaribbean islands. Our investigations led us to propose a daily PM 10 threshold at 35 μg m·3 that mainly associatedwith desert dust phenomenon. This latter is more suited for the Lesser Antilles compared to the European PM10threshold related to desert dust events: 50 μg m·3.As a result, a climatological study of dusty events in the Caribbean during the last decade (2006-2016) is carried out.Four dust seasons were identified: the high dust season (May to August), the low dust season (November to February,and two intermediate periods (March to April, September to October). We then examine dust exportation fromAfrican coasts toward the Lesser Antilles (Puerto Rico, Guadeloupe Martinique and Barbados) by mean of backtrajectories[Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) mode\] displaying atmosphericcirculation day-to-day over the Atlantic Ocean.This analysis enabled us to better understand the seasonal cycle of desert dust transportation, specific to each island(Puerto Rico, Guadeloupe, Martinique, Barbados); while most of the previous studies treats average data including thewhole Caribbean zone. lt emerges that islands are not affected by dust events similarly, i.e. by intensity of events andits includes some variation in dust periods.Lastly, we describe the vertical structure of the tropical zone atmosphere in situation of "desert dust events" and"Non-desert dust event" to observe the thermodynamic effects of minerai aerosols on the Caribbean atmosphericlayer. This analysis allowed us to consider desert dust aerosols effects on the thermodynamic parameters(Temperature and humidity) during the dry-season (November to April) named "câreme" and the wet season (May toOctober) named "hivernage"
25
Farrell, Dana G. "Risk and Protective Factors Associated with the Adult Achievement of Substance-Using Adolescents: Findings from the National Longitudinal Study of Adolescent to Adult Health." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2721.
Full textAbstract:
The literature has well-documented the deleterious effect of alcohol and other drug (AOD) use on adolescent development and future outcomes. Despite these devastating results, some adolescents are able to attain high achievement as adults, despite their earlier AOD use. Secondary quantitative analyses were conducted on nationally-representative data from the National Longitudinal Study of Adolescent to Adult Health. Longitudinal data, collected at Wave I (1994-1995), and Wave IV (2007-2008), were analyzed from a sample of 4,266 American high school students between the ages of 13-19 years. The majority of high school students in the sample self-reported AOD use (n=2,833, 66.4%), compared to those students who self-reported non-AOD-use (n=1,433, 33.6%). Statistically significant findings indicated that with the exception of household income, non-AOD-using adolescents experienced more favorable outcomes with regard to educational attainment, occupational status, and involvement with the criminal justice system when compared to their AOD-using counterparts. In addition, through ordinal and binomial logistic regressions, the present study identified risk and protective factors affecting the adult outcomes of adolescents who used AODs. Gender, age, grade level, importance of religion, frequency of prayer, fighting, suspensions, expulsions, and happiness in neighborhood were statistically significant in predicting educational attainment. Grade level and feeling safe in school were found to be statistically significant in predicting occupational status. Gender, fighting, suspensions, and alcohol use by best friends were statistically significant in predicting involvement with the criminal justice system.
26
Song, Zhili Jack. "Modeling of Gas Flows in Steelmaking Decarburization Processes." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-128541.
Full textAbstract:
The purpose of the current study is to increase the understanding of different steelmaking processes at the decarburization stages by use of mathematical modeling. More specifically, two De-Laval nozzles from a VOD (Vaccum Oxygen Decarburization) process, which is used for producing stainless steels with ultra-low carbon grades, was investigated for different vessel pressures. Moreover, the post combustion phenomena in a BOF or LD (Linz-Donawitz) process as well as an AOD (Argon Oxygen Decarburization) process were studied focusing on the decarburization stage. Two industrial VOD nozzles were numerically studied and compared at different temperatures and ambient pressures. Flow patterns of the oxygen jet under different ambient pressures were predicted and the flow information at different positions from the nozzle was analyzed. In addition, the effects of different ambient temperatures on the jet velocity and the dynamic pressure were compared. The predictions revealed that a little under-expansion is somewhat helpful to improve the dynamic pressure. The jet dynamic pressure and its width for the specific nozzle geometry were also studied. It was observed that a variation in the ambient pressure can influence the jet momentum and its width. In addition, a high ambient temperature was found to have a positive effect on the improvement of the jet dynamic pressure. Furthermore, it was found that a change in ambient pressure has a stronger effect on the jet force than a change in the ambient temperature. In addition, it was proved that the profiles of the dynamic pressure at a certain blowing distance fit well to Multi-Gaussian distribution. Post combustion in a BOF/LD and an AOD process during decarburization was also studied. Two mathematical models were created to show the post combustion phenomenon inside the converters, respectively. For the CFD modeling of the two processes, the realizable k-ɛ model, the species transport model and the discrete ordinate were adopted to calculate the turbulence, gas reaction and radiation present in the gas phase in the converter. For the BOF/LD modeling, a series of plant tests were conducted to collect data, which were used in the current model. These include the off-gas information, emissivity data, oxygen blowing parameters and the chemical composition of steel. After the simulation, the predicted flow pattern and detailed information of the gases taking part in the post combustion were compared to plant data. Specifically, the off-gas data from the plant was used for the model verification. The measured CO2 concentration was 15-20 wt% and the predicted value from the modeling was 16.7 wt%. For the AOD converter of interest in the current work, a fan is installed in the end of the AOD flue to help extract the off-gas from the converter. The influence of different fan gauge pressures as well as temperatures of the gas mixture, containing the generated CO and argon, on the post combustion in the whole AOD system was studied. It was indicated from the modeling results that the post combustion was only present in the flue for the present modeling conditions. Moreover, a critical fan gauge pressure (approx.. -550 Pa) was found which could yield a maximum post combustion in the flue gas. For both two models (BOF/LD and AOD), simulations indicated that a change of the converter temperature from 1500 to 1700 °C did not influence the post combustion reaction to a large degree. In addition, these two models can be regarded as the first step for a future more in-depth modeling work of the post combustion.<br><p>QC 20130913</p>
27
Zuo, Minyu. "Enhanced phosphorus removal from wastewater using virgin and modified slags : performance, speciation and mechanisms." Doctoral thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213415.
Full textAbstract:
Argon oxygen decarburization slag (AOD) was tested in batch and column experiments to investigate its phosphorus (P) removal performance. The effects of factors such as AOD dose, initial P concentration of the feeding solution, and aging on the P removal ability of the slags were analyzed. In a column experiment, electric arc furnace slag (EAF), blast furnace slag (BFS) and AOD were combined in five different ways to determine optimal conditions for P removal. In another column experiment, the three types of slag were modified with polyethylene glycol (PEG) and NaOH to adjust their dissolution properties and the effect on P removal performance was examined. In the batch experiments, AOD exhibited very promising P removal ability. It removed 94.8% of P from 6.5 mg P L-1 synthetic solution in 4 hours with a dose of 5 g L-1. Maximum P removal capacity of 27.5 mg P g-1 was achieved. In the dual-filter column experiment, the column packed with only EAF had the best P removal performance (consistently above 93%). Amorphous calcium phosphate (ACP) was identified as the main P species in the five slag samples collected from the outlet chambers. The contributions from crystalline calcium phosphate (Ca-P) and P adsorbed on iron/aluminum (hydr)oxides were greater in samples from the inlet chambers. The P speciation results revealed that P was predominantly removed by the slags through formation of ACP. The second column experiment showed that modification with PEG and NaOH solution only enhanced short-term P removal by the slags. However, exhaustion of the modified slags occurred much earlier, indicating that the modification process had shortened the lifespan of the slags. Untreated AOD showed better P removal than untreated EAF until pore volume 244, probably due to faster dissolution rate of gamma dicalcium silicate (dominating in AOD according to the XRD results) than of beta dicalcium silicate (dominating in EAF).<br><p>QC 20170830</p>
28
Oliveira, Rafael Porto de. "Desenvolvimento do processo de sopro com lança de 3 furos no convertedor AOD-L da ArcelorMittal Inox Brasil." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/BUOS-8MSEXF.
Full textAbstract:
The AOD converter is the main equipment used on the stainless steels production. The production of stainless steel in AOD-L occurs through injection of a mixture of oxygen and inert gas by tuyères and blowing oxygen by one top lance on the metal bath, to promote the selective carbon oxidation. The process time depends of the nozzle design and the oxygen flow rate. The interaction between the oxygen blown by top lance and the gas injected by the tuyères has an influence on the refine reactions, on the quantity of metal/slag projections and directly affects the metallurgical process results on the AOD-L converter. This work shows the main reasons of the experiment using 3 hole lance in the AOD converter of ArcelorMittal Inox Brazil, replacing the 4-hole lance to blowing oxygen. This work was based in one biography research and the experience of others stainless steel producers to define the configuration of the 3 hole lance used in the experiments. The three holes lances had its opening angle and diameter of the nozzle modified. The experimentswere performed on austenitic stainless steel P304A on the route (EAF-EAF), which uses pre metal from electric arc furnaces and on the route (EAF- PTG) that uses pre metal from the electric arc furnaces and hot metal treated. Using the 3 holes lances the chromium oxidation decreased, the AOD process time reduce, the oxygen and argon specificconsumption reduce, improve AOD desulfurization efficiency with better quality of the cold- rolled strip<br>O convertedor AOD é o principal equipamento utilizado na produção de aços inoxidáveis. O processo de produção do aço inoxidável no AOD-L ocorre através da injeção de uma mistura de oxigênio e gás inerte pelas ventaneiras e sopro de oxigênio pela lança de topo sobre o banho metálico, com o objetivo de promover a oxidação seletiva do carbono. Otempo de sopro depende do projeto do bocal da lança de topo e da vazão de oxigênio de trabalho. A interação entre o jato de oxigênio soprado pela lança de topo com os gases injetados pelas ventaneiras no banho metálico tem influência nas reações de refino, nas projeções de metal/escória e afeta diretamente os resultados metalúrgicos do processo em convertedores AOD-L. O presente trabalho mostra os principais motivos para o experimento utilizando a lança de 3 furos no convertedor AOD-L da ArcelorMittal Inox Brasil em substituição à lança de 4 furos para sopro de oxigênio. O desenvolvimento do trabalho se baseou em uma ampla pesquisa bibliográfica e experiências de outras empresas produtoras de aço inoxidável para definição e configuraçãodo bico da lança de 3 furos utilizada nos experimentos. A lança de 3 furos teve seu ângulo de abertura e diâmetro do bocal modificados. Os experimentos foram realizados no aço inoxidável austenítico P304A nas rotas de produção (FEA-FEA) que utiliza pré metal proveniente dos fornos elétricos à arco e na rota (FEA-PTG) que utiliza pré metalproveniente dos fornos elétricos à arco e ferro-gusa tratado. Com a utilização da lança de 3 furos houve redução da oxidação do cromo, redução do tempo de processo (CTT), redução do consumo específico de oxigênio e argônio, melhor eficiência de dessulfuração no convertedor AOD-L com melhor qualidade do produto final
29
BERGAMO, SONIA. "La scena aperta del consumo di Milano Rogoredo: contesto e pratiche in dialogo." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/306490.
Full textAbstract:
Obiettivo: Nelle ricerche sui consumi di sostanze psicotrope, solitamente il contesto viene trattato come un prodotto di processi strutturali più ampi, riducendo le possibilità di una comprensione più accurata delle specificità locali. Durante il lavoro sul campo (2017-2018), Milano Rogoredo veniva considerata la più grande scena aperta del consumo osservabile nel nord Italia. L’obiettivo della ricerca è quello di documentare come il contesto in esame viene influenzato dalle pratiche di consumo e viceversa.
Metodologia: La ricerca si serve della metodologia del caso studio per raccogliere e mettere in dialogo diversi tipi di informazioni. L’approccio etnografico utilizzato include interviste in profondità e semi strutturate (42), osservazione partecipante (70 giorni), articoli di cronaca, mappe e fotografie. La cornice teorica post-strutturalista, si basa sugli elementi analitici proposti da Duff (2007): spazio, incorporamento e pratiche.
Risultati: La scena aperta del consumo di Rogoredo si configura come un luogo di segregazione socio-spaziale. Le pratiche di consumo che la caratterizzano, creano uno spazio di resistenza nella città tossica. Il disordine droga-correlato percepito dai cittadini porta alla richiesta di purificazione sociale e spaziale. La zona di resistenza che si configura nella scena aperta del consumo fa emergere di legami di comunità e favorisce la diffusione di pratiche di consumo, che richiedono competenze specifiche. La tecnologia della siringa riproduce mondi e divisioni sociali, così come differenze generazionali. La violenza permea le routine e le pratiche quotidiane, che includono lavoro sessuale droga correlato e attività informali di sussistenza. La mancanza di interventi di riduzione del danno strutturati e duraturi riduce lo spazio per negoziare questa violenza.
Limiti/implicazioni: I risultati sono specifici del contesto in cui lo studio è stato condotto. I contatti e le informazioni sono stati raccolti in buona parte attraverso gli interventi di riduzione del danno (gatekeeeper). Considerata la strategia di reclutamento adottata, i consumatori non possono essere considerati come rappresentativi della popolazione di riferimento.
Valore aggiunto: Nonostante un’ampia letteratura internazionale, l’Italia mostra una mancanza di studi sociologici sulle scene aperte del consumo, in particolare per quanto riguarda l’impatto del contesto sulle pratiche locali di consumo. I risultati possono orientare strategie di riduzione del danno più efficaci e fornire delle evidenze iniziali sull’impatto delle misure istituzionali adottate per far fronte alle scene aperte. La ricerca si propone anche come riferimento per future indagini sulle pratiche di consumo di sostanze psicotrope in relazione al contesto.<br>Purpose: In most recent drug research, context is still treated as a product of broad structural processes, reducing the chances for a more finely-grained understanding of time and place of consumption. At the time of the field work, Milano Rogoredo was the biggest urban open drug scene in northern Italy. Starting form this case study, the goal of the present work is to document how the specific context is produced through the activity of drug use and how the so constructed context intervenes in the modulation of drug use itself.
Methodology: In the research, the case study methodology is implied in order to collect and put into dialogue data of different nature. Analysis was conducted through an ethnographic approach which includes in-depth and semi-structured interviews (42), participant observation (70 days), news articles and use of maps and photos. Drawing on a post-structural theoretical framework, the methodology is based on the analytical elements proposed by Duff (2007): space, embodiment and practices.
Findings: Drug use practices embedded in the Milano Rogoredo open drug scene impact on space representations creating a place of resistance in the narcotic city. The so-called drug related nuisance tends to result in a claim for social and spatial purification from citizens. The resistance zone that develops within the open drug scene allows the emergence of community bonds and fosters the spread of drug use practices that involve specific skills. The social object of the syringe reproduces social worlds, social divisions and generational differences. Violence permeates the every-day routines and practices which include drug related sex work and beggary. The lack of structured harm reduction interventions reduces the space to negotiate this violence.
Research limitations/implications: The results are specific of the context in which the study was conducted. Contacts and data were mainly gained starting from harm reduction interventions, since these organisations provide the most accessible contact with drug users. Given the recruitment strategy adopted, individuals who are part of the study cannot be considered as representative of the drug using population as a whole.
Value/practical implications: Despite a wide international literature, Italy shows a lack of sociological accounts of open drug scenes, particularly regarding the impact of context on local drug use practices. This research gives visibility to the effect of the local setting on drug use practices in a long-lasting ODS in Milan (Italy). In the effort to make interventions always more effective, results can orient harm reduction strategies and provide initial evidence on the impact of institutional measures to face ODS. Along with punctual aspects, outcomes can also orient future research on drug consumption practices and context relevance in drug use settings.
30
Silva, Antonio Augusto Gomes dos Santos. "As ONGs como instrumento de política externa no contexto da cooperação internacional para o desenvolvimento : o caso dos Estados Unidos e da Suécia." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/16526.
Full textAbstract:
Dissertação (mestrado)—Universidade de Brasília, Centro de Estudos Avançados Multidisciplinares, Programa de Pós-Graduação em Desenvolvimento, Sociedade e Cooperação Internacional, 2013.<br>Submitted by Raquel Viana (raquelviana@bce.unb.br) on 2014-10-16T20:07:07Z
No. of bitstreams: 1
2013_AntonioAugustoGomesdosSantosSilva.pdf: 14411364 bytes, checksum: 71f6bc67bca3111a0dc6b908d2a67adf (MD5)<br>Approved for entry into archive by Tania Milca Carvalho Malheiros(tania@bce.unb.br) on 2014-10-16T20:23:54Z (GMT) No. of bitstreams: 1
2013_AntonioAugustoGomesdosSantosSilva.pdf: 14411364 bytes, checksum: 71f6bc67bca3111a0dc6b908d2a67adf (MD5)<br>Made available in DSpace on 2014-10-16T20:23:54Z (GMT). No. of bitstreams: 1
2013_AntonioAugustoGomesdosSantosSilva.pdf: 14411364 bytes, checksum: 71f6bc67bca3111a0dc6b908d2a67adf (MD5)<br>A inserção de atores não estatais, como as organizações não governamentais – ONGs, no processo de execução das ações de Ajuda Oficial ao Desenvolvimento (AOD) revela-se significante. As mudanças no contexto internacional, a maior participação da sociedade civil organizada e o advento da globalização, alteraram o conceito do moderno Estado-nação e o próprio Sistema Internacional (SI). Como novo paradigma, examinamos o papel exercido pelas ONGs como executoras da AOD, que permite a inserção no SI. E como os estados utilizam-se dessas estruturas para avançar sua própria política externa, apoiando e financiando suas atividades, muitas delas antes prerrogativas do Estado. O trabalho está dividido em seis segmentos onde, primeiro, foram revistas as teorias que dão sustentação aos constructos de Relações Internacionais pertinentes. Em seguida foram pesquisadas a origem e a evolução das organizações voluntárias, hoje conhecidas como ONGs. Num terceiro segmento foi perscrutada a relação entre a cooperação internacional e a Ajuda Oficial ao Desenvolvimento, tanto por parte dos países doadores, quanto dos beneficiários. Da estrutura em transformação que permite a inserção das ONGs no Sistema Internacional como parceiras de Estados-soberanos ocupou-se a etapa seguinte desse exercício. Tratase de um fenômeno global, que dá sinais de vitalidade nos campos das relações internacionais e da cooperação. Foram comparados, em seguida, os casos de Ajuda Oficial ao Desenvolvimento, seus modelos de recrutamento de parceiros e aplicação de recursos, de dois países, grandes doadores de AOD: os Estados Unidos, maior doador global, e a Suécia, maior doadora em relação à renda nacional bruta (RNB). Consideramos, por fim, os elementos motivadores das doações e parcerias, que podem se situar entre o princípio da solidariedade e um conjunto de objetivos estratégicos dos estados doadores, uma vez que as ONGs encontram-se num campo de conflito de interesses de estados diversos. _______________________________________________________________________________ ABSTRACT<br>The inclusion of non-state actors, such as non-governmental organizations – NGOs, in the process of executing actions of Official Development Assistance (ODA) has shown to be significant. Transformations in the international context, with greater participation of the Organized Civil Society (OSC) and the advent of globalization, have altered the concept of the modern Nation-State, as well as the structure of the International System (IS) itself and encourage an analysis of the role of NGOs in the delivery of ODA, which allows for their inclusion in the IS. States often make use of these structures as tools of their own foreign policy, supporting and financing their activities, many of which, in the past, restricted to States’ own prerogatives. This study is divided into six segments where, firstly, applicable International Relations theories concepts which support this research were scrutinized. The following segment presents an investigation of the origins and the evolution of volunteer organizations which have evolved into our contemporary NGOs. The relationship between international cooperation and ODA methods of aid delivery, both on the donors’ and the beneficiaries’ ends was the subject of the third section of this exercise, followed by an examination of the changing structure of the International System, which allows for NGOs participation, indeed a global phenomenon showing signs of vitality both in the fields of international relations and cooperation. The last two segments attempt at a review of ODA partnership practices and recruiting methods, as well as resources delivery by two large donor countries: the United States as the biggest global donor in absolute numbers and Sweden, the largest donor per Gross National Income (GNI). The final section considers the motivating factors fueling donations to ODA partners, as they may lie between the principles of solidarity and donor States’ own strategic objectives, since NGOs often find themselves operating in areas of conflict of interests of diverse states.
31
Lindholm, Linda. "Inhibition of phosphorus release from sediments of Lake Erhai through argon oxygen decarburisation slag (AOD) and electric arc furnace slag (EAF) capping." Thesis, KTH, Mark- och vattenteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199181.
Full textAbstract:
The effects of eutrophication in lakes and the open seas has been largely the result of phosphorus (P) that accumulate in the sediment. Eutrophication occurs mainly in the waters in densely populated coastal areas and agricultural dominated areas and occurs when an excess of nutrients reach the soil and water. In situ capping is a proven method to inhibit P and is the method used in this study. A capping is placed on the polluted sediment surface to physically isolate it and reduce the release of P and prevent resuspension, i.e. suspension of already precipitated P. The possibility of inhibiting P by using sediment capping and the reactive filter materials (sorbents) argon oxygen decarburisation (AOD) slag in particle size fractions 0-0.5 mm and 2-8 mm and electric arc furnace (EAF) slag in particle size fraction 1-2.36 mm, have been investigated. Soluble reactive phosphorus (SRP), also called orthophosphates, were the main species of P investigated in this study. A total of three studies were conducted in Lake Erhai in Dali China, during April 2016. One pre-study was conducted at ten different sites in the lake, which aimed to find the most P polluted site. This site was chosen for the main study. The main study aimed to investigate if the aforementioned sorbents managed to absorb orthophosphates after contact with lake sediment for seven days. The post-study was conducted to see if the sorbents themselves released any orthophosphates into the water. The water samples were tested for pH, conductivity and dissolved oxygen (DO) before and after contact with lake sediment. The slag materials and lake sediment were studied with inductively coupled plasma (ICP) spectroscopy and X-ray diffraction (XRD) to detect elements and compounds. Obtained results showed that the AOD slag (0-0.5 mm) could absorb 96% of the orthophosphates. However, both the AOD slag (2-8 mm) and EAF slag (1-2.36 mm) showed an increase of orthophosphates in the water after contact with lake sediment. The XRD analysis showed contents of silica (Si) and calcium (Ca) compounds in all of the slag materials, which was expected due to the configuration of these materials. The ICP analysis showed that 2% P was absorbed by the EAF (1-2.36 mm) slag, but there were no absorption by the AOD (0-0.5 mm) or AOD (2-8 mm) slag. The conclusion from this study is that AOD slag (0-0.5 mm) can be used successfully in P remediation projects because it absorbs 96% of the orthophosphates. The results are consistent with previous results from (Zuo et al., 2015) and (Renman et al., 2013).
32
Okamoto, Julia Yuri. "A dinâmica da ajuda externa japonesa: análise empírica sobre os determinantes da assistência oficial para o desenvolvimento de 1961 a 2015." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/101/101131/tde-06022019-114723/.
Full textAbstract:
Este trabalho busca estudar a alocação da assistência oficial para o desenvolvimento (ODA) do Japão no período de 1961 a 2015. A Agência de Cooperação Internacional Japonesa (JICA) tem apontado como motivações da ajuda externa o desenvolvimento econômico e a redução da pobreza em países menos desenvolvidos. A literatura em Relações Internacionais, no entanto, enxerga com ceticismo que os valores humanitários sejam, por si só, determinantes do nível de generosidade do doador, apontando para a importância de elementos domésticos, de fatores normativos internacionais e de considerações político-estratégicas na explicação dos programas de ajuda. Utilizando análise regressiva, esta pesquisa buscará evidências empíricas da importância relativa de diferentes variáveis explicativas da ajuda externa japonesa. Os resultados mostram que os interesses econômicos e político-estratégicos exercem maior influência sobre o programa de assistência do Japão que o nível de pobreza ou o regime democrático nos países beneficiários. Nossas estimativas indicam, ainda, que o Japão tende a concentrar a ajuda em países em desenvolvimento de renda relativamente mais alta, menos populosos e com menores índices de corrupção.<br>The purpose of this research is to study Japan\'s official development assistance (ODA) between 1961 and 2015. Japan International Cooperation Agency (JICA) has cited economic development and poverty reduction in less-developed countries as reasons for providing external aid. However, literature on International Relations is skeptical of humanitarian motives being, on their own, the determinants of donor\'s level of generosity, pointing out the influence of domestic aspects, international statutes, and political and strategical considerations on explaining aid programs. By using regressive analysis, this research will look for empirical evidence of the relative significance of different variables that explain Japanese external aid. The results show that economic and political-strategic interests exert more influence over Japan\'s assistance program than the level of poverty or democratic regime in the beneficiary countries. Our estimates also show that Japan tends to focus aid on relatively higher income developing countries, less populous countries and countries with lower levels of corruption.
33
Attonito, Jennifer. "The Influence of Neurocognitive Impairment, Alcohol and other Drug (AOD) Use, and Psychosocial Factors on Antiretroviral Treatment Adherence, Service Utilization and Viral Load Among HIV-Seropositive Adults." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/968.
Full textAbstract:
Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) can be affected by problems of neurocognitive (NC) impairment, stress, alcohol and other drug (AOD) abuse, and other barriers. The aims of this research were to: (1) examine factors associated with NC impairment, (2) explore relationships between psychosocial variables with ART adherence and viral load (VL), and (3) evaluate the efficacy of an evidence-based intervention in improving ART adherence, increasing service utilization, and decreasing VL.
The first study (n=370) was cross sectional and used structural equation modeling to test whether AOD use, years living with HIV, and time from HIV diagnosis to seeking care were associated with poorer NC functioning. The second study (n=246) used similar methods to test the hypothesis that stress, barriers to adherence, NC impairment, poor social support, and AOD use were related to lower VL mediated by ART adherence. The third study (n=243) evaluated an evidence-based, eight-session program to improve ART adherence, reduce VL, and increase service utilization in a randomized controlled trial. Study participants were PLWH living in South Florida, 18 to 60 years old, with a history of alcohol abuse enrolled from January 2009 through November 2012.
Secondary analysis of available data showed: (1) scores on interference with executive functioning increased by 0.32 for each day of marijuana use and 1.18 for each year living with HIV, but no association was found between alcohol use and NC functioning; (2) each barrier to adherence was associated with a 10% decrease in adherence to ART and a 0.42 unit increase in VL (log10) and the relationship between barriers and VL was partially mediated by ART adherence; (3) participants in the evidence-based program were more likely than the comparison group to report an undetectable VL (OR=2.25, p
Psychosocial factors affect VL, but ART adherence is essential in achieving an undetectable VL in PLWH.
34
Gustafsson, Matilda, and Von Platen Hanna Nordin. "En jämförande kolonnstudie av två reaktiva dualfilters egenskaper som långvarig fosforfälla i enskilda avlopp - En jämförelse av dualfiltrena Polonite® -Sorbulite® och AOD-Hyttsand." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211560.
Full textAbstract:
Eutrofieringen av Östersjön är omfattande och ses i dag som ett av områdets allvarligaste föroreningsproblem. Orsaken till detta är en förhöjd näringsbelastning av kväve och fosfor. Den ökade näringsbelastningen beror på att de naturliga flödena av dessa näringsämnen har rubbats, vilket är en direkt följd av urbaniseringen. Sveriges enskilda avlopp står för 16% av den totala fosforbelastningen till Östersjön. År 2006 skärptes de svenska riktvärdena för fosforbelastning från enskilda avloppsanläggningar. Nästan en tredjedel av dagens 625 000 enskilda avloppsanläggningar klarar inte dessa skärpta krav. Som ett led i detta har forskning och utveckling inom ämnesområdet bedrivits under de senaste 20 åren. Forskningen har resulterat i nya effektivare avloppsreningstekniker där så kallade reaktiva filtermaterial används som fosforfälla. Gemensamt för de reaktiva filtermaterial som har utvecklats är dess höga kalciumhalt och stora specifika fastläggningsytor, vilket vid höga pH-värden skapar förutsättning för en hög fosforfastläggningen. Den reaktiva filtermaterialstekniken möjliggör ett resurseffektivt användande av fosfor då recirkulation av grundämnet möjliggörs. Syftet med detta kandidatexamensarbete har varit att undersöka om livslängden för två olika reaktiva filtermaterial kan förlängas genom en dualfilterteknik. En teknik där fosforfällan består av två olika reaktiva filtermaterial med olika egenskaper. Hypotesen har varit att en dualfilterteknik kan minska kalciumutlakningen från filtret. De två dualfilter som har undersökts är Polonite®–Sorbulite® och Argon oxygen decarburisation–Hyttsand. Arbetet har utförts som en kolonnstudie. De viktigaste analyserna som har genomförts är alkalinitet och kalciumutlakning. Arbetes slutsatser listas nedan: o Det dualfilter som har visat bäst förutsättningar som långvarig fosforfälla i enskilda avloppsanläggningar är Polonite®–Sorbulite®. o Materialet Sorbulite® har visat sig kunna minska kalciumutlakningen, vilket bekräftar studiens hypotes. Arbetets resultat pekar på att Sorbulite® kan användas för att förlänga filterlivslängden för det reaktiva filtermaterialet Polonite® . o Materialet Hyttsand uppvisar ingen förmåga till att kunna samla upp utlakade kalciumfraktioner. Detta medför att Hyttsand ej är ett lämpligt material i ett dualfilter där syftet är att förlänga filtrets livslängd.
35
Zabukovec, Antonin. "Apport des mesures de la plateforme CALIPSO pour l’étude des sources et des propriétés optiques des aérosols en Sibérie." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS393.
Full textAbstract:
Les connaissances sur la distribution et les propriétés physico-chimiques des particules aérosols dans la troposphère ont été identifiées par le Groupe d’experts Intergouvernemental sur l’Évolution du Climat (GIEC) comme la principale source d’incertitude dans l’étude de l’évolution du climat. Une caractérisation des types, des propriétés optiques et de la distribution verticale des aérosols à l’échelle régionale est nécessaire pour réduire cette source d’incertitude et certaines zones comme la Sibérie sont encore mal documentées. Les concentrations en aérosol de la Sibérie dépendent de sources naturelles, comme les feux de forêt saisonniers ou le transport vers le nord des poussières désertiques, mais également des sources anthropiques comme celles des zones exploitations d’hydrocarbures ou le transport à longue distance des émissions du Nord de la Chine. Afin de contribuer à l’amélioration de cette caractérisation des sources d’aérosol en Sibérie, nous avons dans un premier temps analysé les mesures de deux campagnes aéroportés réalisées sur des distances de plusieurs milliers de km en juillet 2013 et juin 2017. L’avion était équipé d’un lidar à rétrodiffusion à 532 nm ainsi de mesures in-situ de monoxyde de carbone (CO), de carbone suie (BC) et des distributions en taille des aérosols. Ces observations ont été étudiées en synergie avec celle du lidar spatial CALIOP et des missions MODIS et IASI. La gamme d'altitude des couches d'aérosols et le rôle de l’âge sur les propriétés optiques (épaisseur optique (AOD532), dépolarisation, rapport de couleur) sont discutés pour chaque type d'aérosol. Les résultats d’un vol au-dessus des régions d’extraction du gaz correspond au plus fortes AOD532, et des concentrations en BC supérieure à celle des émissions des zones urbaines et a permis une estimation du rapport lidar de ces panaches d'aérosols mal documentés dans la littérature. La deuxième partie du travail a consisté à proposer une alternative à la restitution indirecte de l’AOD532 par l’instrument CALIOP à partir de l’inversion du signal lidar de rétrodiffusion atténué. Cette méthode utilise la réflectance du signal lidar de CALIOP par la surface et a déjà été utilisée au-dessus des océans ou des nuages d’eau liquide optiquement opaques pour calculer une valeur AOD. Dans ce travail, nous avons ainsi développé et évalué une restitution des AOD à partir de la réflectance CALIOP de surface pour les zones continentales. Deux méthodologies ont été utilisées afin de déterminer la réflectance lidar de surface non atténuée par les aérosols: (i) sélection des observations CALIOP en condition de ciel clair sur 7 ans d’observation (ii) extrapolation de la relation de linéarité entre la réflectance lidar de surface atténuée et la transmission atmosphérique. Si ces deux méthodes donnent de bons résultats dans les zones de faible réflectance lidar de surface (< 0.75 sr-1) la première méthode n’est pas utilisable sur les zones désertiques. L’utilisation de ces AOD lidar mesurées directement au-dessus des surfaces continentales permet d’améliorer le biais (|ME| < 0.034) et la dispersion (< 0.145) en comparaison aux observations MODIS. Ceci améliore beaucoup les résultats des comparaisons CALIOP-MODIS obtenus avec la restitution indirecte des AOD une analyse des profils verticaux de rétrodiffusion lidar atténuée avec un biais < 0.174 et une dispersion < 0.234<br>Knowledge of the distribution and physico-chemical properties of aerosol particles in the troposphere has been identified by the Intergovernmental Panel on Climate Change (IPCC) as the main source of uncertainty in the study of climate change. Characterization of the types, optical properties and vertical distribution of aerosols at the regional scale is needed to reduce this source of uncertainty and some areas such as Siberia are still poorly documented. Aerosol concentrations in Siberia depend on natural sources, such as seasonal forest fires or northward transport of desert dust, but also on anthropogenic sources such as those from hydrocarbon mining areas or long-range transport of emissions from northern China. In order to contribute to the improvement of this characterization of aerosol sources in Siberia, we first analyzed the measurements of two airborne campaigns carried out over distances of several thousand km in July 2013 and June 2017. The aircraft was equipped with a back-scattering lidar at 532 nm, as well as in-situ measurements of carbon monoxide (CO), black carbon (BC) and aerosol size distributions. These observations were studied in synergy with those of the CALIOP spaceborne lidar and the MODIS and IASI missions. The altitude range of the aerosol layers and the role of age on the optical properties (optical thickness (AOD532), depolarization, color ratio) are discussed for each type of aerosol. The results of a flight over the gas extraction regions corresponded to the highest AOD532 and higher BC concentrations than the emissions from urban areas and allowed an estimation of the lidar ratio of these aerosol plumes poorly documented in the literature. The second part of the work consisted in proposing an alternative to the indirect restitution of the AOD532 by the CALIOP instrument from the inversion of the attenuated back-scattering lidar signal. This method uses the surface reflectance of the CALIOP lidar signal and has already been used over oceans or optically opaque liquid water clouds to calculate an AOD value. In this work, we have thus developed and evaluated an AOD restitution from the CALIOP surface reflectance for continental areas. Two methodologies were used to determine the surface lidar reflectance not attenuated by aerosols: (i) selection of CALIOP observations under clear sky conditions over 7 years of observation (ii) extrapolation of the linearity relationship between attenuated surface lidar reflectance and atmospheric transmission. If these two methods give good results in areas of low surface lidar reflectance (< 0.75sr-1), the first method is not usable in desert areas. The use of these LIDAR AOD measured directly over continental surfaces improves the bias (|ME| < 0.034) and dispersion (< 0.145) compared to MODIS observations. This greatly improves the results of the CALIOP-MODIS comparisons obtained with the indirect restitution of the AODs an analysis of the vertical profiles of attenuated lidar backscatter with a bias < 0.174 and dispersion < 0.234
36
SILVA, Lenardo Chaves e. "Uma abordagem baseada em modelos para suporte à validação de sistemas médicos físico-cibernéticos." Universidade Federal de Campina Grande, 2015. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/625.
Full textAbstract:
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-09T17:24:59Z
No. of bitstreams: 1
LENARDO CHAVES E SILVA - TESE PPGCC 2015..pdf: 9863003 bytes, checksum: b4ff7a7517f3ec159596b4b3c8730219 (MD5)<br>Made available in DSpace on 2018-05-09T17:24:59Z (GMT). No. of bitstreams: 1
LENARDO CHAVES E SILVA - TESE PPGCC 2015..pdf: 9863003 bytes, checksum: b4ff7a7517f3ec159596b4b3c8730219 (MD5)
Previous issue date: 2015-11-12<br>Capes<br>Sistemas Médicos Físico-Cibernéticos (SMFC) são sistemas críticos cientes de contexto
que têm a segurança do paciente como principal requisito, demandando processos rigorosos de validação para garantir a conformidade com os requisitos do usuário e a corretude orientada à especificação. Neste trabalho é proposta uma arquitetura baseada
em modelos para validação de SMFC, focando em promover a reúso e a produtividade.
Tal abordagem permite que desenvolvedores de sistemas construam modelos formais
de SMFC baseados em uma biblioteca de modelos de pacientes e dispositivos médicos,
bem como simular o SMFC para identificar comportamentos indesejados em tempo de projeto. A abordagem proposta foi aplicada a três diferentes cenários clínicos para
avaliar seu potencial de reúso para diferentes contextos. A abordagem foi também validada por meio de uma avaliação empírica com desenvolvedores para avaliar o reúso e
a produtividade. Finalmente, os modelos foram formalmente verificados considerando
os requisitos funcionais e de segurança, além da cobertura dos modelos.<br>Medical Cyber-Physical Systems (MCPS) are context-aware, life-critical systems with
patient safety as the main concern, demanding rigorous processes for validation to
guarantee user requirement compliance and specification-oriented correctness. In this
article, we propose a model-based approach for early validation of MCPS, focusing on
promoting reusability and productivity. It enables system developers to build MCPS
formal models based on a library of patient and medical device models, and simulate
the MCPS to identify undesirable behaviors at design time. Our approach has been
applied to three different clinical scenarios to evaluate its reusability potential for different context. We have also validated our approach through an empirical evaluation with developers to assess productivity and reusability. Finally, our models have been
formally verified considering functional and safety requirements and model coverage.
37
Hesaraki, Sareh. "Comparisons of an aerosol transport model with a 4-year analysis of summer aerosol optical depth retrievals over the Canadian Arctic." Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/9809.
Full textAbstract:
Abstract : This is a study concerning comparisons between the Dubovik Aerosol optical depth (AOD) retrievals from AEROCAN (ARONET) stations and AOD estimates from simulations provided by a chemical transport model (GEOS-Chem : Goddard Earth Observing System Chemistry). The AOD products associated with the Dubovik product are divided into total, fine and coarse mode components. The retrieval period is from January 2009 to January 2013 for 5 Arctic stations (Barrow, Alaska; Resolute Bay, Nunavut; 0PAL and PEARL (Eureka), Nunavut; and Thule, Greenland). We also employed AOD retrievals from 10 other mid-latitude Canadian stations for comparisons with the Arctic stations. The results of our investigation were submitted to Atmosphere-Ocean. To briefly summarize those results, the model generally but not always tended to underestimate the (monthly) averaged AOD and its components. We found that the subdivision into fine and coarse mode components could provide unique signatures of particular events (Asian dust) and that the means of characterizing the statistics (log-normal frequency distributions versus normal distributions) was an attribute that was common to both the retrievals and the model.<br>Résumé : Cette étude compare des épaisseurs optiques d’aérosols (AOD) à 5 stations arctiques d’AEROCAN (AERONET), obtenues d’une part à l’aide de l’algorithme d'inversion de Dubovik appliqué à des mesures in situ, et d’autre part du modèle de transport chimique (GEOS-Chem : Goddard Earth Observing Système Chemistry). Les produits d’AOD associés à l’algorithme d’inversion sont divisés en composantes totales, fines et grossières. Pour chacune des 5 stations (Barrow, Alaska, Resolute Bay, au Nunavut, 0PAL et PEARL (Eureka), Nunavut, et Thulé, au Groenland), la période de récupération est de janvier 2009 à janvier 2013. Nous avons également utilisé les mesureurs d’AOD de dix autres stations canadiennes de latitudes moyennes, à des fins de comparaison. Les résultats de l’étude ont été soumis à la revue Atmosphere-Ocean. Pour résumer brièvement ces résultats, le modèle a généralement, mais pas toujours, eu tendance à sous-estimer l'AOD moyenne et de ses composantes. Nous avons constaté que la subdivision en composantes fine et grossière pourrait fournir des signatures uniques d'événements particuliers (poussière asiatique) et que les moyens de caractériser des statistiques (les distributions de fréquence log-normale versus les distributions normales) était un attribut qui était commun aux deux les mesureurs et le modèle.
38
Filho, Decio Sartori Felix. "Avaliação do efeito do volume e da vazão de gás na recuperação de metais oxidados no processo de produção do aço inoxidável em conversores AOD." Universidade Federal de Minas Gerais, 2009. http://hdl.handle.net/1843/BUOS-8DRK2W.
Full textAbstract:
O conversor AOD é o principal equipamento utilizado na produção de aços inoxidáveis. O processo de produção do aço inoxidável no AOD ocorre através da injeção de uma mistura de oxigênio e gás inerte no banho metálico, com o objetivo de fazer a oxidação seletiva do carbono. Porém, durante esta etapa, ocorre também a oxidação de metais nobres, tais como cromo e, para que o processo seja economicamente viável, é necessário recuperar este cromo oxidado através da adição de agente redutor e injeção de gás inerte. A otimização da fase de redução permite a redução do tempo de processamento do aço no conversor contribuindo para elevar sua produtividade. No presente trabalho, foi avaliado, então, o efeito do aumento da vazão e a redução do tempo de injeção do gás inerte na etapa de recuperação dos metais oxidados do conversor AOD-L da ArcelorMittal Inox Brasil. Atualmente, o volume de argônio injetado na fase de redução do aço inoxidável austenítico é de 550 Nm3 e a vazão de 52Nm3/min. Neste trabalho foram testadas alterações no volume e na vazão do gás injetado na fase de redução, simultaneamente. De posse dos resultados experimentais, foi realizada uma análise estatística dos dados sobre a eficiência da recuperação do cromo bem como da remoção do enxofre e do nitrogênio no aço inoxidável austenítico ACE P304A. As análises estatísticas realizadas neste trabalho evidenciam que o aumento da vazão e a alteração do volume de argônio injetado possibilitam a redução do tempo de processamento sem afetar os resultados atuais de custo e qualidade das placas produzidas. A partir dos resultados obtidos, recomenda-se alterar a vazão de argônio para 77Nm3/min e o volume para 620 Nm3, reduzindo o tempo de processamento em 2,5 minutos e elevando a produtividade do AOD em mais de 2 toneladas por hora.
39
Majuste, Daniel. "Tratamento da lama fina gerada na lavagem de gases do convertedor AOD-L, na produção de aço inoxidável, visando à recuperação de cromo e níquel." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/BUOS-9LUMR3.
Full textAbstract:
In 2004, around 24 thousand t of AOD-L sludge were generated by ACESITA S/A in the stainless steel making process. The fine fraction of this material, around 15 thousand t, constitutes an environmental liability containing Fe, Cr and Ni. Techniques such as briquetting and magnetic separation aiming to recycle this material have not shown satisfactory results. Therefore, based on Its granulometry and also on its content of Ni and Cr, the use of hydrometallurgy was investigated in this study in order to treat the fine fraction of the AOD-L sludge. The study included the characterization and leaching of the sludge. The sludge is constituted by a fine powder (mean diameter of 1 nm) containing (33 ± 2) % w/w of
moisture content and it was classified as hazardous waste (class I). X-Ray diffraction analysis has identified the following crystalline phases: chromium-bearing magnetite (Cr-FeaO^), hematite (Fe203), calcite (CaCOs) and chromite (FeCr204), this latter a spinel oxide that is
very difficult to dissolve in aqueous solutions. Scanning Electron Microscopy with Energy-Dispersive Spectrometry has pointed out that Ni is present in very fine particles, possibly in the metallic form or associated with Fe and O elements. The sludge presented the following
chemical composition (in % w/w): (33,9 ± 1,6) of Fe; (10,2 ± 0,9) of Cr; (1,4 ± 0,1) of Ni, and other elements such as Ca, Mg, Mn and Si. The leaching was carried out in two steps: Leaching LI, aiming to reduce the Fe content with consequent Cr and Ni concentration in the sludge; and Leaching L2, aiming to maximize Cr and Ni extraction. For LI, the following operating factors were investigated: type of leaching agent (H2SO4 and HCI), temperature (25, 40, 55 and 70°C) and acid concentration (3, 6 and 12 % v/v). In this operation, a higher extraction of Fe and Ni were obtained, in comparison to the extraction of Cr. The best separation factors and Fe extraction levels were obtained in hydrochloric media. For the LI operation, the content of Fe in the sludge was reduced around 50 % w/w while Cr was concentrated approximately 100 % w/w. The main disadvantages of LI are the high extraction of Ni (around 40 % w/w) and the excessive consumption of acid. For L2, the tests were carried out at 140°C and atmospheric pressure condition. In the experiments, the following operating factors were investigated: H2SO4 concentration (60 and 65 % v/v) and HCI04/sludge ratio (0 and 4 mL/g). Higher extractions of Cr and Ni associated to lower extractions of Fe were obtained. The addition of HCIO4 favors the chromite dissolution and also the selectivity to Cr and Ni in detriment of Fe. The increase on the H2SO4 concentration, on the other hand, has not favored the selectivity of operation and resulted on the decrease of the metal extractions. However, the technique limitation of the experimental apparatus used for the L2 tests requires the investigation of this step at high pressure conditions.<br>Em 2004, foram geradas pela ACESITA S/A cerca de 24 mil t de lamas na lavagem de gases do convertedor AOD-L, na produção do aço inoxidável. A fração fina deste material, cerca de 15 mil t, constitui um passivo ambiental contendo Fe, Cr e Ni. Técnicas como aglomeração
por briquetagem e separação magnética visando a sua reciclagem no processo não apresentaram resultados satisfatórios. Neste sentido, em função da granulometria do material e teores de Cr e Ni na lama fina (LF), estudou-se a possibilidade de aplicação da hidrometalurgia como alternativa de tratamento do resíduo. Assim, no presente trabalho, fez-se um estudo da caracterização e lixiviação da LF. Verificou-se que este resíduo, classificado como resíduo perigoso (classe I), é constituído de partículas com diâmetro médio de 1 iam, e teor de umidade de (33 ± 2) % m/m. Análises por DRX identificaram as fases cristalinas magnetita contendo Cr (Cr-Fe304), hematita (Fe203), calcita (CaCOa) e cromita (FeCr204), óxido este um mineral do grupo dos espinéiios, de difícil dissolução em meio aquoso. Nas análises por MEV/EDS identificou-se o Ni em partículas muito finas, possivelmente sob a forma metálica
ou associado ao Fe e O. A amostra de LF utilizada no estudo apresentou a seguinte composição química (em % m/m): (33,9 ± 1,6) de Fe; (10,2 ± 0,9) de Cr; e (1,4 ± 0,1) de Ni, além de outros elementos como Ca, Mg, Mn e Si. A lixiviação foi realizada em duas etapas: Lixiviação LI, objetivando-se reduzir o teor de Fe, com conseqüente concentração de Cr e Ni no sólido; e Lixiviação L2, visando a extração total dos metais. Para a LI, os fatores operacionais investigados foram: tipo de agente lixiviante (H2SO4 e HCI), temperatura (25, 40, 55 e 70°C) e concentração de ácido (3, 6 e 12 % v/v). Nesta operação, maiores extrações percentuais de Fe e Ni foram obtidas, em comparação aos percentuais de extração de Cr. A maior seletividade e os maiores percentuais de extração de Fe foram obtidos com HCI. Na LI, foi possível reduzir o teor de Fe contido na LF em torno de 50 % m/m, associado a uma concentração de, aproximadamente, 100 % m/m de Cr na mesma. Como desvantagens, porém, tem-se uma extração de Ni em torno de 40 % m/m e um alto consumo de ácido. A Lixiviação L2 foi estudada em temperatura elevada (HO^C) e em pressão atmosférica, sendo os fatores investigados a concentração de H2SO4 (60 e 65 % v/v) e a relação HCIO4/LF (O e 4 mL/g). Nessa operação, maiores extrações percentuais de Cr e Ni, associadas a menores extrações percentuais de Fe, foram obtidas. A adição de HCIO4 favoreceu a dissolução de Cr e a seletividade para o Cr e Ni em detrimento do Fe. O aumento da concentração de H2SO4, por sua vez, não favoreceu a seletividade do processo e resultou na diminuição dos percentuais de extração dos metais. A limitação técnica do aparato experimental utilizado nos ensaios da L2, entretanto, exige a investigação dessa operação em pressões elevadas.
40
Zidane, Shems. "Caractérisation, modélisation et validation du transfert radiatif d'atmosphères non standard : impact sur les corrections atmosphériques d'images de télédétection." Thèse, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/6486.
Full textAbstract:
Cette étude est basée sur des données multi-altitudes aéroportées acquises en juillet 2004 lors d'un événement atmosphérique inhabituel dans la région de Saint-Jean-sur-Richelieu. Nous entendons en cela une atmosphère dont la distribution des aérosols ne respecte pas les variations habituellement implémentée dans les codes de transfert radiatifs. Les surfaces au sol imagées pendant cette campagne de terrain couvraient une variété spectrale assez diversifiée, à savoir des surfaces agricoles, des plans d'eau et des zones urbaines et forestières. L'aspect multi-altitude de cette acquisition de données a permis de caractériser les mêmes cibles au sol avec des contributions de l'atmosphère variant en fonction de l'altitude considérée afin de caractériser au mieux la perturbation observée durant cette campagne et de permettre une meilleure caractérisation de la perturbation apportée par une variation non-standard (panache de fumée). La transformation de la luminance apparente aux trois altitudes en réflectance apparente et l'implémentation de la perturbation apportée par le panache de fumée dans un modèle classique a permis une correction atmosphérique appliquée aux deux altitudes les plus hautes. Les résultats ont démontré une cohérence avec les réflectances apparentes de validation qui confirmait la véracité de notre modélisation du cas non-standard. Ces résultats ont d'autant plus étés pertinent [i.e. pertinents] pour la plus haute altitude de 3,17km : la réflectance apparente à cette altitude est au dessus de la majeur [i.e. majeure] partie du panache de fumée et intègre une bonne proportion de la perturbation apportée par ce panache, ce qui représente un test probant de notre capacité à corriger adéquatement l'influence de cette perturbation. Les perturbations atmosphériques standard sont évidemment prises en compte dans la majorité des modèles atmosphériques, mais ceux-ci sont souvent basés sur des variations monotones des caractéristiques physiques de l'atmosphère avec l'altitude. Lorsque la radiation atmosphérique est perturbée, par un panache de fumée ou un événement de pollution atmosphérique local et non standard, cela nécessite une modélisation et une modification adéquate des modèles existants en fonction des paramètres que l'on pourra obtenir sur ladite perturbation. Les intrants principaux de cette étude étaient ceux normalement utilisés lors d'une correction atmosphérique classique à savoir les luminances apparentes mesurées par un imageur aéroporté mais à trois altitudes différentes et l'épaisseur optique des aérosols (AOD) qui était acquise depuis le sol. La méthodologie que nous avons employé [i.e. employée] utilise aussi un code de transfert radiatif (CAM5S, pour Canadian Modified 5S, qui vient directement du code de transfert radiatif 5S dans le visible et proche infrarouge). Cependant il nous faudra aussi avoir recours à d'autres paramètres et données afin de modéliser correctement la situation atmosphérique particulière présente sur les images multi-altitude acquises pendant la campagne de terrain à Saint-Jean-sur-Richelieu. Nous avons alors élaboré un protocole de modélisation de perturbation atmosphérique non standard où une gamme de données auxiliaires disponibles est venue compléter nos données principales. Cela a permis l'élaboration d'une méthodologie robuste et relativement simple adaptée à notre problématique. Ces données auxiliaires, à savoir des données météorologiques, des profils LEDAR, différentes images satellites et des données de photomètres solaires qui ont permis la détermination de la fonction de phase des aérosols, ont été suffisantes pour établir une modélisation adéquate du panache de fumée observé en terme de distribution verticale non monotone des paramètres physiques relevés lors de cette campagne. Cette distribution non-standard à été par la suite interprétée en terme de profil spécifique de l'AOD qui a remplacé les profils des AOD employés dans le modèle de correction atmosphérique CAM5S. En fonction de cette modélisation, nous montrons que l'erreur entre les réflectances apparentes au sol obtenu [i.e. obtenue] par le processus de correction atmosphérique et les réflectances apparentes au sol provenant du processus de validation dR*(0), moyenné quadratiquement à travers les bandes visibles, reste majoritairement dans une gamme inférieure à 0,01 d'erreur quadratique moyenne des R*(0) après avoir modélisé la perturbation non-standard, ce qui permet une estimation plus acceptable des réflectances multi-altitude et du biais existant entre la prise en compte et la non prise en compte de cette perturbation dans le modèle atmosphérique. D'importants écarts ont néanmoins été observés, majoritairement attribuables à la difficulté apportée par les conditions d'acquisition, les grandes disparités observées entre l'échantillonnage des mêmes surfaces aux trois altitudes, et probablement des erreurs de modélisation et/ou de calibration. La nécessité d'améliorer le processus d'acquisition, de modélisation et de prévision de telle perturbation est largement décrit dans ce document afin de permettre à l'avenir d'établir un protocole d'acquisition plus adapté grâce notamment à une surveillance et un suivi des perturbations atmosphériques maintenant possible grâce aux outils décrits. L'originalité de cette étude réside dans une nouvelle approche de la caractérisation de ces perturbations atmosphériques par l'incorporation d'une structure non standard dans un modèle de correction atmosphérique opérationnel et de démontrer que cette approche présente des améliorations significatives des résultats par rapport à une approche qui ignore la perturbation du profil vertical standard tout en utilisant des valeurs d'AOD totaux correctement mesurés. Le modèle de profil que nous avons employé était simple et robuste, mais a capturé suffisamment de caractéristiques du panache pour réaliser des améliorations significatives en termes de précision de correction atmosphérique. Le processus global d'aborder tous les problèmes rencontrés dans l'analyse de notre perturbation des aérosols nous a aidé à construire une méthodologie appropriée pour caractériser ces événements sur la base de la disponibilité des données, distribué gratuitement et accessibles à la communauté scientifique. Cela rend cette étude adaptable et exportable à d'autres problématiques du même genre.
41
Sič, Bojan. "Amélioration de la représentation des aérosols dans un modèle de chimie-transport : modélisation et assimilation de données." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2667/.
Full textAbstract:
L'objectif général de cette thèse est d'améliorer la représentation des aérosols dans le modèle MOCAGE. Pour se faire, nous avons modifié directement la représentation des aérosols en réexaminant et améliorant les différents processus déjà présents via la prise en compte de schémas et de paramétrisations plus détaillés et implémenté l'assimilation de données des aérosols dans le modèle. Les processus ayant subi les améliorations les plus importantes sont les émissions des aérosols du type sel marin, poussière désertique et cendre volcanique, le dépôt humide et la sédimentation. Nous avons évalué les impacts de ces changements et comparé les champs modélisés avec des observations. Les modifications implémentées ont permis d'améliorer significativement l'accord entre modèle et observations. Comme approche complémentaire pour répondre à l'objectif de cette thèse, nous avons également implémenté dans le CTM MOCAGE l'assimilation de données des aérosols. Le système d'assimilation de données des aérosols est implémenté et il est capable d'assimiler l'épaisseur optique des aérosols (AOD) et les mesures lidar. L'assimilation des observations d'AOD est un outil efficace pour améliorer les performances du modèle en terme d'AOD et de concentration. L'assimilation de mesures lidar sur le signal ainsi que les coefficients de rétrodiffusion et d'extinction, ont montré un impact efficace sur les profils verticaux<br>The main goal of this thesis is to improve the aerosol representation in the CTM MOCAGE. The work may be divided into: the direct improvement of aerosol physical parameterizations, and the development of a data assimilation system able to assimilate aerosol optical depth (AOD) and lidar profiles. On the modelling side, the processes that underwent the important improvements were sea salt, desert dust and volcanic aerosol emissions, wet deposition and sedimentation. The ambition is related to improve the model biases compared to observations, and to implement more physically detailed schemes in the model. We evaluated the impacts of these changes and compared the modelled fields to observations. The implemented updates significantly enhanced the model agreement with the observations and the inter-model comparison data. The results also confirmed that large uncertainties in models can come from the use of different parameterizations. The aerosol data assimilation is implemented to further reduce the model uncertainties. The set of observation operators and their tangent linear and adjoint operators for AOD and lidar profile observations are developed to link the model and the observation space. Aerosol assimilation proved to be very efficient to reduce the differences between the model and the observations. The assimilated AOD observations were able to significantly improve the model performance in terms of AOD and concentrations. Assimilation of lidar measurements: the backscatter signal, the extinction and backscatter coefficients, also showed an efficient influence on the vertical profiles
42
Lee, Susan Kaye. "Alcohol, tobacco and other drug concerns of newly arrived 'CaLD' (culturally and linguistically diverse) women in Perth." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/1590.
Full textAbstract:
Womens Health Services (WHS) in Perth provides medical services, counselling, information, community talks and workshops, referral, and outreach to women in Western Australia. WHS works with women from over sixty different nationalities, including many newly arrived migrants and refugees. New arrivals access a wide range of WHS programs, but at the time the current study was developed few ethnic women attend the alcohol and other drug (AOD) services offered by the organisation. To address this a needs assessment was conducted with newly arrived women (0 to 5 years in Australia). The needs assessment examined the use of alcohol and other drugs by newly arrived women, the barriers that prevent women from accessing alcohol and other drug (AOD) services and explored the types of services and programs newly arrived women wanted.Method. The needs assessment used both qualitative and quantitative methods. Twenty two service providers working with newly arrived migrant and humanitarian entrant women were either interviewed individually or attended a focus group. The views and experiences of 26 newly arrived women from a variety of culturally and linguistic backgrounds were also collected through one-on-one interviews (n=6) and through focus groups (n=5). The information gathered from these interviews and discussions informed the design of a questionnaire that was administered to 268 newly arrived women. All women participating in the project were 18 years of age or more, Australian citizens, permanent Australian residents or in the process of being granted permanent residency and had lived in Australia 5 years or less.Findings Regarding Tobacco and Alcohol Use. Australian cultural attitudes had had an impact on newly arrived women's alcohol and other drug use. Some impacts were positive, for example, increasing restrictions and the decrease in acceptability of smoking in public places along with strong educational messages about the risk of smoking had influenced some women to quit since coming to Australia. Unfortunately, not all Australian cultural attitudes had a positive impact on newly arrived women. Just under one third of the women (31.7%) who drank alcohol were drinking more alcohol since coming to Australia. Reasons for drinking more alcohol were varied and included alcohol being cheaper in Perth than in their own countries, socialising with Australians who drank alcohol, and using alcohol as a way of coping with stress. However, it is important to note that only a very small percentage of the newly arrived women participating in the needs assessment drank at levels considered risky or high risk for either short term or longer term harm. The vast majority of respondents surveyed did not smoke (n=207; 77.2%) and did not use alcohol (n=201; 76.1%), often due to cultural or religious reasons.Other Results. Other findings of the needs assessment included: • Over 21% of newly arrived women responding to the survey had been put in fear by some one under the influence of alcohol and/ or drugs. Nearly 17% of women responding to the survey had been verbally abused by some one under the influence of alcohol and/ or drugs. • More than one third of the women responding to the survey indicated that they wanted information and support on family violence. • Over 40% of the women responding to the survey wanted information and support for depression. • Forty women (14.9%) responding to the survey wanted support for husbands or children that were drinking too much alcohol.A surprising finding was the high level of interest in women's only exercise classes and opportunities to participate in other types of physical activity Two thirds of questionnaire respondents said that exercise was a priority for them. Subsequent feedback sessions with newly arrived women about the results of the needs assessment confirmed the need for opportunities to participate in a variety of physical activities in a safe, affordable, women only environment where childcare was available.Understandings of Alcohol and Other Drug Services. Participants in the study appeared to have a poor understanding of what AOD services were, different types of treatments and models that could be used, who was entitled to access them (not just the alcohol or other drug user), the associated costs and fees, and whether or not the police would become involved. There was a significant lack of understanding by service providers working with newly arrived women about eligibility to access alcohol and drug services and what assistance and support these agencies could provide either to women using alcohol and other drugs or to family and friends impacted by another's drug use. Few service providers asked their clients any questions about alcohol or other drug use on a regular basis.The findings from the needs assessment have been used to improve programs and services with newly arrived women at WHS. These have included the addition of a specific alcohol and other drugs program for women from culturally and linguistically diverse backgrounds with a focus on prevention activities as well as opportunities for newly arrived women to participate in a variety of physical activity classes.
43
Martin, Joseph S. "Aerosol optical depth model assessment with high resolution multiple angle sensors." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FMartin.pdf.
Full textAbstract:
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, Dec. 2004.<br>Thesis Advisor(s): Philip A. Durkee. Includes bibliographical references (p. 35-36). Also available online.
44
Wehrmeister, Marco Aurélio. "An aspect-oriented model-driven engineering approach for distributed embedded real-time systems." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17792.
Full textAbstract:
Atualmente, o projeto de sistemas tempo-real embarcados e distribuídos está crescendo em complexidade devido à sua natureza heterogênea e ao crescente número e diversidade de funções que um único sistema desempenha. Sistemas de automação industrial, sistemas eletrônicos em automóveis e veículos aéreos, equipamentos médicos, entre outros, são exemplos de tais sistemas. Tais sistemas são compostos por componentes distintos (blocos de hardware e software), os quais geralmente são projetados concorrentemente utilizando modelos, ferramentas e linguagens de especificação e implementação diferentes. Além disso, estes sistemas tem requisitos específicos e importantes, os quais não representam (por si só) as funcionalidades esperadas do sistema, mas podem afetar a forma como o sistema executa suas funcionalidades e são muito importantes para a realização do projeto com sucesso. Os chamados requisitos não-funcionais são difíceis de tratar durante todo o ciclo de projeto porque normalmente um único requisito não-funcional afeta vários componentes diferentes. A presente tese de doutorado propõe a integração automatizada das fases de projeto de sistemas tempo-real embarcados e distribuídos focando em aplicações na área da automação. A abordagem proposta usa técnicas de engenharia guiada por modelos (do inglês Model Driven Engineering ou MDE) e projeto orientado a aspectos (do inglês Aspect-Oriented Design ou AOD) juntamente com o uso de plataformas previamente desenvolvidas (ou desenvolvida por terceiros) para projetar os componentes de sistemas tempo-real embarcados e distribuídos. Adicionalmente, os conceitos de AOD permitem a separação no tratamento dos requisitos de naturezas diferentes (i.e. requisitos funcionais e não-funcionais), melhorando a modularização dos artefatos produzidos (e.g. modelos de especificação, código fonte, etc.). Além disso, esta tese propõe uma ferramenta de geração de código, que suporta a transição automática das fases iniciais de especificação para as fases seguintes de implementação. Esta ferramenta usa um conjunto de regras de mapeamento, que descrevem como elementos nos níveis mais altos de abstração são mapeados (ou transformados) em elementos dos níveis mais baixos de abstração. Em outras palavras, tais regras de mapeamento permitem a transformação automática da especificação inicial, as quais estão mais próximo do domínio da aplicação, em código fonte para os componentes de hardware e software, os quais podem ser compilados e sintetizados por outras ferramentas para se obter a realização/implementação do sistema tempo-real embarcado e distribuído.<br>Currently, the design of distributed embedded real-time systems is growing in complexity due to the increasing amount of distinct functionalities that a single system must perform, and also to concerns related to designing different kinds of components. Industrial automation systems, embedded electronics systems in automobiles or aerial vehicles, medical equipments and others are examples of such systems, which includes distinct components (e.g. hardware and software ones) that are usually designed concurrently using distinct models, tools, specification, and implementation languages. Moreover, these systems have domain specific and important requirements, which do not represent by themselves the expected functionalities, but can affect both the way that the system performs its functionalities as well as the overall design success. The so-called nonfunctional requirements are difficult to deal with during the whole design because usually a single non-functional requirement affects several distinct components. This thesis proposes an automated integration of distributed embedded real-time systems design phases focusing on automation systems. The proposed approach uses Model- Driven Engineering (MDE) techniques together with Aspect-Oriented Design (AOD) and previously developed (or third party) hardware and software platforms to design the components of distributed embedded real-time systems. Additionally, AOD concepts allow a separate handling of requirement with distinct natures (i.e. functional and non-functional requirements), improving the produced artifacts modularization (e.g. specification model, source code, etc.). In addition, this thesis proposes a code generation tool, which supports an automatic transition from the initial specification phases to the following implementation phases. This tool uses a set of mapping rules, describing how elements at higher abstraction levels are mapped (or transformed) into lower abstraction level elements. In other words, suchmapping rules allow an automatic transformation of the initial specification, which is closer to the application domain, in source code for software and hardware components that can be compiled or synthesized by other tools, obtaining the realization/ implementation of the distributed embedded real-time system.
45
Harley, Judith Ann. "Mental Health Consumers' Perspectives on Traditional Mental Health Services Versus Peer-Run Services: A Qualitative Study." Ashland University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ashland1352125523.
Full text
46
Kang, Lei. "Reduced-Dimension Hierarchical Statistical Models for Spatial and Spatio-Temporal Data." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1259168805.
Full text
47
Samuelsson, Peter. "Management of technology in the process industries: Matching market and machine." Doctoral thesis, KTH, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199705.
Full textAbstract:
The process industries span multiple industrial sectors and constitute a substantial part of the entire manufacturing industry. Since companies belonging to this family of industries are often very asset intensive, their ability to respond to changes is often limited in the short term. The adaptation of the capabilities of existing processes, and conversely finding products and market segments to match the production system capabilities, are an important part of product- and market development activities in the process industry. The importance to companies in the process industry of having a well-articulated manufacturing strategy congruent with the business strategy is second to none. However, to facilitate manufacturing strategy developments, it is essential to start with an improved characterization and understanding of the material transformation system. To that end an extensive set of variables was developed and related measures and scales were defined. The resulting configuration model, focusing on company generic process capabilities in the process industries, is to be regarded as a conceptual taxonomy and as a proposition available for further testing. The usability of the model was subsequently assessed using “mini-cases” in the forestry industry, where the respondents confirmed that the company’s overall strategy could benefit from this kind of platform as a possible avenue to follow. The model was deployed as an instrument in the profiling of company material transformation systems to facilitate the further development of companies' functional and business strategies. The use of company-generic production capabilities was studied in three case companies representing the mineral, food and steel industries. The model was found by the respondents to be usable as a knowledge platform to develop production strategies. In the final analysis of the research results, a new concept emerged called “production capability configuration": A process-industrial company’s alignment of its generic production capabilities in the areas of raw materials, process technology and products to improve the consistency among the variable elements that define operations and improve the congruence between operations and its environment. From the perspective of value creation and capture, firms must be able to manufacture products in a competitive cost structure within the framework of a proper business model. By using the configuration model, the relationship between manufacturing and innovation activities has been studied in the previously mentioned three case studies. In many cases the gap in capability appears as a limitation in the production system, requiring development efforts and sometimes investments to overcome. This is illustrated with two examples from the steel industry, where development efforts of the production system capabilities are initiated to better match the market demands. One example is the increase the volume- and product flexibility of an existing stainless steel melt shop, resulting in a proposed oblong Argon Oxygen Decarburisation (AOD) converter configuration that was subsequently verified using water modelling. The second example is from a carbon steel mill, where the target was to increase the raw material- and volume flexibility of another melt shop, by modifying the capabilities of the Electric Arc Furnace (EAF). Enabling EAF technologies are further described and evaluated using operational data and engineering type of estimates.<br><p>QC 20170116</p>
48
Kornberger, Martin, Stephan Leixnering, Renate Meyer, and Markus Höllerer. "Rethinking the sharing economy: The nature and organization of sharing in the 2015 refugee crisis." AOM, 2017. http://dx.doi.org/10.5465/amd.2016.0138.
Full textAbstract:
Our paper focuses on a non-standard sharing example that harbors the potential to disrupt received wisdom on the sharing economy. While originally entering the field to analyze, broadly from a governance perspective, how the 2015 refugee crisis was handled in Vienna, Austria, we found that the non-governmental organization Train of Hope - labeled as a "citizen start-up" by City of Vienna officials - played an outstanding role in mastering the crisis. In a blog post during his visit in Vienna at the time, and experiencing the refugee crisis first-hand, it was actually Henry Mintzberg who suggested reading the phenomenon as part of the "sharing economy". Continuing this innovative line of thought, we argue that our unusual case is in fact an excellent opportunity to discover important aspects about both the nature and organization of sharing. First, we uncover an additional dimension of sharing beyond the material sharing of resources (i.e., the economic dimension): the sharing of a distinct concern (i.e., the moral dimension of sharing). Our discovery exemplifies such a moral dimension that is rather different from the status quo materialistic treatments focusing on economic transactions and property rights arguments. Second, we hold that a particular form of organizing facilitates the sharing economy: the sharing economy organization. This particular organizational form is distinctive - at the same time selectively borrowing and skillfully combining features from platform organizations (e.g., use of technology as an intermediary for exchange and effective coordination, ability to tap into external resources) and social movements (e.g., mobilization, shared identity, collective action). It is a key quality of this form of organization to enable the balancing of the two dimensions inherent in the nature of sharing: economic and moral. Our paper contributes to this Special Issue of the Academy of Management Discoveries by highlighting and explaining the two-fold economic and moral nature of sharing and the organization of sharing between movement and platform.
49
Alshahrani, Mohammed A. S. "Oral and nasal infectivity and immunogenicity of Plasmodium berghei and yoelii sporozoites and longevity of Plasmodium falciparum trophozoites and schizonts." Thesis, Bangor University, 2017. https://research.bangor.ac.uk/portal/en/theses/oral-and-nasal-infectivity-and-immunogenicity-of-plasmodium-berghei-and-yoelii-sporozoites-and-longevity-of-plasmodium-falciparum-trophozoites-and-schizonts(69df2a18-9a6d-4ee5-922d-bb11332f86f0).html.
Full textAbstract:
Malaria is one of the most problematic diseases that human being has ever confronted. The quest for an effective, robust vaccine has been going on for more than a century. The whole Plasmodium sporozoites vaccine strategy has proven to be the best approach for eliciting up to 70% protection and for up to 6 months after the last immunization. Most of the robust vaccines that we have nowadays against several microbiological organisms are given by either oral or nasal routes. Infectivity and immunogenicity of Plasmodium berghei ANKA and P. yoelii Nigeriensis sporozoites have never been tested against BALB/c or C57BL/6 mice after being inoculated via oral and nasal routes. Results of this study show that inoculation of sporozoites of the species P. berghei or P. yoelii into BALB/c or C57BL/6 mice are infective and immunogenic. Furthermore, there was a cross-reactivity between the two parasite species when tested against several synthetic peptides. These findings shed light on the importancy of the oral and nasal canal as routes for experimentations of the immunization regime. The large subunit vaccines development concentrated on the erythrocytic stage of malaria parasites has generated disappointing results, Therefore, there is currently a renewed focus on the whole Plasmodium blood stage parasite. In the current study, we aim to assess whether it is possible to obtain a living, whole entity of the blood stage that can be kept alive under minimal conditions and ideally without cryopreservation which could be used in developing countries a live, whole organism blood stage vaccine. we examined the viability as well as the invasiveness potency of Plasmodium falciparum parasites after being isolated from RBCs and incubated at 37˚C and RT. We showed here that the Plasmodium parasites were able to retain their invasiveness for 16 days despite being incubated at far lower temperature (at RT) than the optimal temperature. Also we showed that the Plasmodium falciparum at late trophozoites and early schizonts were capable to remain viable for 10 months (nearly 300 days) outside the RBCs at RT. The diversity of malaria disease in animals is larger ecologically and systematically than we commonly expected. The Plasmodium genus is a member within the order Haemosporidia, is consider one of the largest genus in this order, and currently encompass more than 250 Plasmodium species. Most of these species have only been defined morphologically. Most animals show simultaneous infections with more than one species of Plasmodium and most species descriptions originated from such multiple infections, which prevents the molecular characterization of most Plasmodium species as sequence data cannot be assigned to particular morphospecies. We have successfully developed genus- and species-specific FISH probes based on the small and large ribosomal subunit for Plasmodium falciparum as a proof of concept for the interrogation of animal morphospecies of Plasmodium parasites. This will open up the future for molecular screening of animal malaria, not only in blood samples but also in fecal samples, and might lead to a better understanding of the epidemiology and ecology of malaria parasites in many animal species in temperate and in tropical regions.
50
Lalor, Kay. "Uneven encounters and paradoxical rights : embodiment and difference in sexual orientation rights and activism." Thesis, University of Westminster, 2012. https://westminsterresearch.westminster.ac.uk/item/8z3xv/uneven-encounters-and-paradoxical-rights-embodiment-and-difference-in-sexual-orientation-rights-and-activism.
Full textAbstract:
My thesis takes the intersection of sexual orientation and human rights and the increased tendency towards the expression of the concerns of sexual minorities in rights based terminology in international law as a Deleuzian ‘problem’ to be explored and unpicked. Sexual orientation is a singular expression of a complex multifaceted virtuality, yet the term -‐ understood as a static and relatively unchanging denotation of a particular identity and mode of action -‐ holds increasing purchase as a human rights issue. I explore the way in which rights shape the expression of sexuality within institutional and activist practices in international arenas and suggest that the complex and contested encounter between sexuality and human rights in international law exposes the problems, limits and temporality of both. By taking seriously the problems inherent to the encounters between sexuality and rights, as they are expressed in different material circumstances, we can explore sexuality as a mutliplicitous and changing flux and rights as a dual sided paradox, acting simultaneously machines of territorialisation and machines of deteritorialisation. Thus, I suggest that in their engagement with questions of 'sexual orientation', rights act as both modes of control, restriction and exclusion and as modes of communication and connection, challenge and escape, depending upon the particular circumstances within which they are expressed. As such, I attempt to engage with the embeddedness of ‘sexuality’ within particular material contexts and through this engagement, explore different potentialities that are implicated within divergent enactments of rights and sexuality in order to critique a mode of action that remains fixed upon abstract discussion of ossified ‘sexualities’ and transcendental rights. Furthermore, my aim is to approach the encounter not only as a means of critique but also as a moment of uncertainty and a site of productive engagement, vitality and becoming. Thus, the key question to be asked of the encounter between sexual orientation and rights is not one of which rights have been violated or of how a perceived violation can be expressed in relation to an already conceived and fixed discourse of rights, but instead, which material circumstances have facilitated the expression of injustice suffered by a sexual minority as a rights violation and in expressing the violation in this way, which possibilities, problematics and discourses are activated, and which others are ignored.