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Xu, Yao. "Analysis of dam failures and diagnosis of distresses for dam rehabilitation /." View abstract or full-text, 2010. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202010%20XU.
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Al, Maqbali Nasser. "Risk assessment of dams." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09ENS/09ensa316.pdf.
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Bibliography: leaves 101-104. Explores risk assessment of dams, a fundamental approach for dam safety measurement, providing a base on which all safety assessment and any appropriate regulation should be developed. Includes an overview of the relevant literature; an example of the application of this method by the South Australia Water Corporation; and it is also applied to the Wadi Al Jizzi Recharge Dam in the Sultanate of Oman. Conclusions and recommendations are presented on the applicability of risk assessment of dams method in the Sultanate of Oman.
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Imbrogno, David F. "Analysis of Dam Failures and Development of a Dam Safety Evaluation Program." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406168902.
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Lismanis, Brandon. "Numerical Modelling of Dam Breaching." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24004.
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Until recently, research has been scarce in the field of physical modelling of dam breaching. Over the past few years, teams from the University of Ottawa, Canada, Delft University of Technology, Netherlands, and HR Wallingford, United Kingdom have worked on several physical models to help determine how various dam breaching characteristics vary due to changes in dam geometry and geotechnical properties. The purpose of this project is to use these new experimental data sets to compare and validate the applicability range of two existing pieces of software, MIKE11-DB and BREACH developed by the Danish Hydraulic Institute and National Weather Service, respectively. Several breaching characteristics such as the outflow hydrograph, peak flow, lag time, breaching time, breach width, and water level are considered in the present study. A sensitivity analysis is also performed on the model’s main input parameters and their sensitivity and performance is ranked accordingly.
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Wishart, Jeremy Scott. "Overtopping Breaching of Rock-Avalanche Dams." Thesis, University of Canterbury. Civil Engineering, 2007. http://hdl.handle.net/10092/1193.
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River blockages formed by rock avalanches appear to pose a higher hazard potential than other landslide dams, given the extreme run-out distances and volumes of rock avalanche deposits. Recent research has identified rock avalanche deposits to have internal sedimentology consisting of a coarse surficial material (carapace) and a finer fragmented interior (body) potentially of critical importance to rock-avalanche dam stability. Physical scale modelling of overtopping failure and breach development in rock avalanche dams was used to quantify the influence of this sedimentology on critical breach parameters, and their prediction using existing embankment dam breach technologies. Results from this study indicate that the time to failure for rock avalanche dams is approximately twice that observed for homogeneous dams due to the armouring properties of the carapace; and that peak discharge is not significantly affected by sedimentology. While application of empirical, parametric, dimensional and physically based models indicated that uncertainty associated with predicted dam break discharges could range from ±19% to ±107%, no modelling technique was able to simulate the armouring phenomenon adequately. Comparison of actual and simulated breach evolution shows linear assumptions of breach depth and width development (as observed in homogeneous dams) to be incorrect. In the context of hazard management, the results suggest that empirical regression relationships should be used for rapid assessment of potential dam break flood magnitude.
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Boughoufalah, Mohamed. "Earthquake input mechanisms for dam-foundation interaction." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63932.
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Bag, Firat. "Numerical Simulation Of The Cinarcik Dam Failure On The Orhaneli River." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605843/index.pdf.
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This thesis analyzes the probable outcome of the fictitious failure of a dam under a set of pre-defined scenarios, within the framework of a case study, the case subject being the Cinarcik Dam located within Bursa Province of Turkey. The failure of the dam is not analyzed neither structural nor hydraulic-wise but is assumed to be triggered when certain critical criteria are exceeded. Hence, the analyses focus on the aftermath of the failure and strive to anticipate the level of inundation downstream of the dam itself. For the purpose of the analyses, the FLDWAV software developed by the National Weather Service of USA is used to spatially and temporally predict the flow profiles, water surface elevations and discharges occurring downstream of the Çinarcik Dam under the defined set of scenarios. Based on these analyses, indicative inundation maps and settlements under risk will be identified, and the thesis study will further address some available pre-event measures that may be taken in advance.
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Durieux, Johan Hendrik. "Development of a practical methodology for the analysis of gravity dams using the non-linear finite element method." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-06232009-152815/.
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Reynolds, Sonel. "Evaluating the decision criteria for the prioritisation of South African dams for rehabilitation in terms of risk to human lives." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80288.
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Thesis (MScEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: In South Africa a large number of dams owned by the Department of Water Affairs (DWA) need to be rehabilitated. This study investigated the decision process involved in the prioritisation of dams for rehabilitation. DWA developed a risk analysis methodology for defining the risks associated with dam safety, expressed as the combination of the probability and consequences of dam failure. These risks are evaluated usingmultiple acceptability criteria to assess risk to human life and the economic, social, socio-economic and environmental impacts of dam failure. In this study, the criteria used in the decision process to evaluate the acceptability of life safety risks were evaluated by comparing to international best practice methods, where the acceptability of risk to human life is commonly assessed as the expected number of fatalities against life safety criteria presented as FN-criteria on an FN-diagram. Damrehabilitation should reduce the probability of dam failure, thereby reducing the risk to society in terms of the expected lives lost. However, the rehabilitation works come at a cost and the level of these investments are usually large. In addition, the rehabilitation of South African government owned dams are financed by society and these financial resources are limited. Thus investments into dam rehabilitation works should be worthwhile for society. Society’s Willingness to Pay (SWTP) for safety was applied to South African dam safety to determine the acceptable level of expenditure into life safety that is required by society. Investments into improved safety levels are not always dictated by society, but could also be driven by the decision maker or owner requiring an economically optimal solution for the rehabilitation. Economic optimisation accounts for considerations additional to life safety, including economic motivations, damage costs of dam failure as well as compensation costs for lives lost. Often economic optimisation would govern the decision problem. Also, the DWA current evaluation does not take the cost of rehabilitation into account in any way. Thus, FN-criteria that primarily evaluates life safety, but also incorporates a measure of economic efficiency, were suggested in this study.
AFRIKAANSE OPSOMMING: In Suid-Afrika moet ’n groot aantal dammewat deur dieDepartement vanWaterwese (DWA) besit word gerehabiliteer word. Hierdie studie het die besluitnemingsproses ondersoekwat toegepasword om damme te prioritiseer vir rehabilitasiewerke. DWA het ’n bestaande metodologie wat gebaseer is op risiko-analise. Die risikos wat verband hou met damveiligheid word deur die metode bepaal en word uitgedruk as die kombinasie van waarskynlikheid en die beraamde gevolge van damfaling. Hierdie risikosword geëvalueer teenoor verskeie kriteriawat die aanvaarbaarheid van risikos teenoor menselewens en die ekonomiese, sosiale, sosio-ekonomiese en omgewingsimpakte van damfalings assesseer. In hierdie studie word die kriteria wat gebruik word in die besluitnemingsproses om die aanvaarbaarheid van risikos teenoor menselewens te bepaal geëvalueer deur die kriteria te vergelyk met metodes wat internasionaal as beste praktyk beskou word. Internasionaal word die aanvaarbaarheid van risikos teenoor menselewens oor die algemeen as die verwagte aantal sterftes teenoor lewensveiligheidskriteria FN-kriteria op ’n FN-diagram geassesseer. Dam rehabilitasiewerke behoort die waarskynlikheid van damfaling te verminder, sodoende verminder die risiko teenoor die samelewing in terme van verwagte sterftes. Die rehabilitasiewerke vereis finansiële beleggings, en hierdie beleggings is gewoonlik groot. Verder word die rehabilitasie van Suid-Afrikaanse damme wat deur DWA besit word deur samelewing gefinansier en hierdie finasiële hulpbronne is beperk. Dus moet hierdie beleggings die moeite werd wees vir die samelewing. Die samelewing se bereidwilligheidomte betaal ("SWTP") vir veiligheid word toegepas in Suid- Afrikaanse damveiligheidomdie aanvaarbare vlak van beleggings vir ’n verbeterde veiligheid teenoor menselewens wat deur die samelewing vereis word te bepaal. Beleggings in verbeterde damveiligheidsvlakke word egter nie altyd bepaal deur die samelewing nie,maar kan ook gedryf word deur die besluitnemer of eienaar wat ’n ekonomies optimale oplossing vir die rehabilitatiesewerke vereis. Ekonomiese optimering neem oorwegings addisioneel tot lewensveiligheid in ag, insluitend ekonomiese motiverings, skade kostes as die dam faal, sowel as vergoedingskostes vir die verwagte sterftes. Ekonomiese optimering beheer dikwels die besluitnemingsprobleem. Verder neem die huidige DWA besluitnemingssproses in geen manier die kostes van rehabilitasie in ag nie. Dus word FN-kriteria wat hoofsaaklik veiligheid teenoor menselewens evalueer,maar wat ook ’n mate van ekonomiese doeltreffendheid insluit, voorgestel in hierdie studie.
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Soliday, Stanley Jr. "Limits of limit equilibrium and finite element techniques applied to cracked debris dams on collapsing foundations." PDXScholar, 1991. https://pdxscholar.library.pdx.edu/open_access_etds/4428.
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Limits of slope stability, limit equilibrium methods, and of the finite element code FEADAM are reached in the application of these methods to the problem of cracked dams constructed on collapsing soils.
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Karakaya, Koray. "Numerical Simulation Of The Kirazlikopru Dam Failure On The Gokirmak River." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606039/index.pdf.
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Numerical dam break analyses of Kirazliköprü
Dam are performed under various hydraulic scenarios. Kirazlikö
prü
Dam is located on the Gö
kirmak River near the city of Bartin. The objective of these analyses is to investigate adverse effects of such dam break failure on the regions downstream of the dam. The numerical model used in the simulations is FLDWAV, which is developed by the National Weather Service (NWS) in the United States. It appears that most adversely effected regions are those that are closest to the dam location. The results of these simulations can be used sufficiently to prepare emergency action plans in case of possible failures.
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Wästlund, Dag. "Progressive failure research on foundation surface of the Longtan gravity dam." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-161213.
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The most common failure of concrete gravity dams is sliding along the foundation surface. This thesis studies progressive failure of the Longtan dam on the upper Hongshuie river in china.Two methods are used in this thesis; the Safety Reserve Factor (SRF) method and the Overload method. The SRF-method is used as a tool to study sliding failure along the foundation weak layer of the Longtan dam. Strength reduction coefficients decrease the cohesion and friction angle values for the weak layer of the foundation. Simulations with reduced shear strength parameter values gives information about the development of the plastic zone. The ultimate bearing resistance and the failure path along the foundation are obtained. The safety reserve coefficient is established through the strength reduction coefficients, when the plastic zone of the foundation is totally coalescent. To analyse the development of the plastic zone along the dam foundation with the strength reserve method, the commercial finite element software MSC.Marc is used. The results of the Safety Reserve Factor method (SRF) show that the failure of the dam is highly related to the strength of the interface between the dam and rock foundation. The strength reserve factor is determined to 2.4. The Overload method gives a visual deformation shape of the dam structure and pressure load at the moment of failure.Dammar har används i mer än 5000 år (Yang et al. 1999) och är fortfarande en viktig källa för energiutvinning. Det största antalet dammar finns i Kina och man tror att det finns över 80,000 dammar i landet (Shapiro 2001). En ökning av dammars kapacitet och antal sker, vilket resulterat i ett behov av bättre sätt för att utvärdera säkerhetsparametrar som betongkvalité, styvhet och homogenitet av bergmassa. Simuleringar av dammkonstruktioner kan ge värdefull information om dessa parametrar och kan därigenom bidra till att förbättra en damms stabilitet och sänka konstruktionskostnader. I det här examensarbetet utvärderas och modelleras Longtan dammen i övre Hongshui floden i Kina. Den vanligaste orsaken till haveri av betongdammar är glidning mellan betonglager och bergmassan. I den här rapporten simuleras ett svagare lager mellan betong och bergmassa och utvecklingen av kontaktbrottsvägen visualiseras och utvärderas med progressiva haveri metoden. Det svagare lagrets hållfasthetskoefficienter; friktionsvinkel och kohesion, reduceras för att analysera utbredningen av den plastiska zonen. Resultaten visar att en överskridning av draghållfastheten för betong börjar vid dammens häl och att kompressionsbristningsgränsen överskrids vid dammens tå när hållfasthetskoefficienterna reduceras. Säkerhetsreservskoefficienten för Longtan dammen erhålls då gränsytan mellan betong och berg är helt plastisk. För att analysera utbredningen av den plastiska zonen längs med dammfundamentet med progressiva haveri metoden används den kommersiella finita element mjukvaran MSC.Marc. Resultaten från säkerhetskoefficientfaktormetoden visar att ett haveri av gravitations dammar är i hög grad relaterad till hållfastheten mellan betongen och bergets gränsyta. Säkerhetskoefficientfaktorn bestäms till 2.4. För att bestämma Longtan dammens maximala vattenbelastningskapacitet används Överbelastningsmetoden. Det maximala vattentryck som Longtan dammen klarar av utan att haverera simuleras med hjälp av en vätska vars densitet ökas mellan modellkörningar. Dammens förskjutning når till sist en punkt där den ökar kraftigt och dammens mutationsdeformationstillstånd har uppnåtts. En visuell deformationsbeskrivning av dammen ges genom modellkörningar och överbelastningsfaktorn bestäms.
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Charatpangoon, Bhuddarak. "SEISMIC SAFETY EVALUATION OF EARTH DAM AND POSSIBLE REHABILITATION METHODS." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/192169.
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REGMI, Ram Krishna. "Study on Failure of Landslide Dam and Slope." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/151954.
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Fu, Chaoran, and Bjartmar Hafliðason. "Progressive failure analyses of concrete buttress dams : Influence of crack propagation on the structural dam safety." Thesis, KTH, Betongbyggnad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169707.
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Concrete buttress dams are the most common type of concrete dams for hydropower production in Sweden. Cracks have been observed in some of the them. However, only limited research has been made concerning the influence of these cracks on the structural dam safety. In conventional analytical stability calculations, a concrete dam is assumed to be a rigid body when its safety is verified. However, when cracks have been identified in a dam structure, the stability may be influenced and hence the information of cracks may need to be included in the stability calculations. The main aim of this project is to study how existing cracks and further propagation of these cracks, influence the structural dam safety. Another important topic was to study suitable methods to analyse a concrete dam to failure. In addition, a case study is performed in order to capture the real failure mode of a concrete buttress dam. The case study that has been studied is based on a previous project presented by Malm and Ansell (2011), where existing cracks were identified in a 40m high monolith, as a result from seasonal temperature variations. Two similar models are analysed where one model is defined with an irregular rock-concrete interface, and the other with a horizontal interface. Analyses have been performed on both an uncracked concrete dam but also for the case where information regarding existing cracks, from the previous project, have been included in order to evaluate the influence of cracks on the dam safety. The finite element method has been used as the main analysis tool, through the use of the commercially available software package Abaqus. The finite element models included nonlinear material behaviour and a loading approach for successively increasing forces called overloading, when performing progressive failure analyses. The results show that existing cracks and propagation of these resulted, in this case, in an increased structural safety of the studied dam. Furthermore, an internal failure mode is captured. The irregular rock-concrete interface has a favourable effect on a sliding failure and an unfavourable effect on an overturning failure, compared to the case with the horizontal interface. Based on the results, the structural safety and the failure mode of concrete buttress dams are influenced by existing cracks. Although an increased safety is obtained in this study, the results do not necessarily apply for other monoliths of similar type. It is thus important that existing cracks are considered in stability analyses of concrete buttress dams.Lamelldammar är den vanligaste typen av betongdammar för vattenkraft produktion i Sverige. I vissa av dessa har sprickbildning observerats. Begränsad forskning har gjorts på hur dessa sprickor påverkar dammens säkerhet. I de vedertagna analytiska stabilitetsberäkningarna antas att betongdammar agerar som en stel kropp när man verifierar dess säkerhet. Befintliga sprickor i en damm kropp kan dock påverka dess stabilitet och kan därför behöva beaktas i stabilitetsberäkningarna. Huvudsyftet med detta projekt är att studera hur befintliga sprickor och dess propageringen påverkar dammsäkerheten. Ett annat viktigt syfte är att studera lämpliga metoder för att analysera en betongdamm till brott. Dessutom, genomförs en fallstudie i syfte att analysera ett verkligt brottförlopp av en lamelldamm. Fallstudien som utförs i detta projekt, baseras på ett tidigare projekt utfört av Malm and Ansell (2011), där befintliga sprickor identifierades i en monolit på 40m som ett resultat av temperaturvariationer. Två modeller med snarlik geometri har analyserats, där den ena är definierad med en med oregelbunden kontaktyta mellan berg och betong och den andra med en horisontell kontaktyta. Analyserna har utförts på dels en osprucken damm men även där information om befintliga sprickor från det tidigare projektet beaktas, i syfte att jämföra inverkan av sprickor på dammsäkerheten. Finita element metoden har använts som verktyg vid dessa analyser, genom det kommersiellt använda programmet Abaqus. De finita element modellerna inkluderar icke-linjära material egenskaper hos betong och armering samt baseras på en metod för successiv belastning, som kallas 'overloading', vid analys av brottförloppet. Resultatet visar att befintliga sprickor och propageringen av dessa i detta fall kan leda till ökad säkerhet hos den studerade dammen jämfört mot fallet utan beaktande av sprickbildning. Utöver detta fångas även ett inre brottmod. Den oregelbundna kontaktytan mellan betongen och berget har en gynnsam effekt vid ett glidbrott men en ogynnsam inverkan vid ett stjälpningsbrott, i jämförelse med fallet med en horisontell kontaktyta. Baserat på dessa resultat så påverkas dammens säkerhet och brottetförloppet hos lamelldammen utav befintliga sprickor. Även om en ökad säkerhet fås i denna studie är det inte säkert att detta stämmer för andra monoliter av samma slag. Dock är det viktigt att hänsyn tas till befintliga sprickor i stabilitets analyser av lamelldammar.
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Dounias, George Theodoros. "Progressive failure in embankment dams." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/8350.
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Hrabová, Kristýna. "Riziko vodohospodářských staveb z pohledu tzv. černých labutí." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254239.
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The thesis is focused on the issue of black swans in the water structure. More detail risks and hazard dam. History has shown us that sophisticatedly structure as dam is not perfect. Failure can cause weather, natural disaster, bad chance or deliberate attack. A detailed analysis of the current situation, I mapped historic dam failure, which can cause black swan. In thesis is a reseach on knowledge of the population in this issue. Based on the analysis and obteined information was proposed measures to improve the situation.
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Ferreira, Bernardo Menezes Rodrigues. "Building automation with failure tolerance." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23823.
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Mestrado em Engenharia de Computadores e TelemáticaEsta dissertação enquadra-se no projecto SmartLighting e tem como objectivo criar uma solução energeticamente eficiente para edifícios e espaços inteligentes. Numa primeira fase, esta dissertação apresenta uma revisão das soluções existentes de automação de edifícios e, posteriormente, propõe uma solução baseada em princípios da Internet das Coisas e sistemas de processamento complexo de eventos, capaz de criar um ambiente inteligente, autónomo e resiliente a falhas. O foco do trabalho está na criação de um software leve para ser colocado em dispositivos com pouca capacidade de processamento de modo a poderem, não só ser um meio para comunicação com dispositivos inteligentes, mas também habilitados para oferecer capacidades de processamento de eventos em casos de emergência.
This dissertation was was done within the scope of the SmartLighting project and aims to create an energy efficient solution for buildings and smart spaces. In a first phase, this dissertation presents a review of existing building automation solutions and later proposes a solution based on Internet of Things (IoT) principles and Complex Event Processing (CEP) systems, capable of creating a smart, autonomous and fail resilient environment. The focus of the work is on creating a lightweight software to be placed on devices with low processing capacity so that they can not only be a means of communicating with intelligent devices but also enabled to provide event processing capabilities in cases of emergency.
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Awal, Ripendra. "Study on Landslide Dam Failure Due to Sliding and Overtopping." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/66199.
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Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第14136号
工博第2970号
新制||工||1441(附属図書館)
26442
UT51-2008-N453
京都大学大学院工学研究科社会基盤工学専攻
(主査)教授 中川 一, 教授 関口 秀雄, 教授 藤田 正治
学位規則第4条第1項該当
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Broberg, Lisa, and Malin Thorwid. "Evaluation of Failure Modes for Concrete Dams." Thesis, KTH, Betongbyggnad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169708.
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The safety of a concrete dam is ensured by designing according to failure criteria, for all combinations of loads using safety factors. Today in Sweden, RIDAS, the Swedish power companies’ guidelines for dam safety, is used for the design of dams and is based on BKR, the National Board of Housing, Building and Planning. Swedish dams are designed to resist two global failure modes; sliding and overturning. Combination of failure modes, that should be considered in the design of concrete dams, is however fairly unknown. Since 2009 the Eurocodes was adopted and came into force 2011. The Eurocodes have replaced BKR in the design of most structures in Sweden where the partial factor method is used to ensure safety in the design. The objective of this report was to examine if the design criteria for concrete dams in today’s condition are enough to describe real failure modes. The other objective was to analyse if Eurocode is comparable to RIDAS in dam design. The stated questions were answered by performing a literature study of known dam failures and analytical calculations for different types of concrete gravity dams, with varying geometry and loading conditions. The programs CADAM and BRIGADE were also used as calculation tools to further analyse if failure occurred as expected. The results from the analytical calculations together with the performed FE analysis indicate that limit turning does occur and often generate lower safety factors compared to overturning. Limit turning is similar to overturning failure although it accounts for material failure in the rock. This design criterion is therefore, highly dependent on the quality of the rock and requires investigations of the foundation to be a good estimation of the real behaviour of the dam body. From the compilation of reported failures the conclusion was that the current design criteria are adequate. However, the real challenge lies in ensuring that the construction of dams is correctly performed to fulfil the stated criteria. A transition to Eurocode appears to be reasonable for the stability criterion. A modification of the partial factors is nevertheless necessary to obtain result corresponding to RIDAS, especially for the overturning criteria.För att uppnå säkra dammkonstruktioner, för alla lastkombinationer, dimensioneras dammar enligt bestämda brottvillkor som ska uppfylla en viss säkerhetsfaktor. Idag används RIDAS, för dimensionering av dammar i Sverige. RIDAS Kraftföretagens riktlinjer för dammsäkerhet, är baserat på BKR, Boverkets konstruktionsregler. I Sverige dimensioneras dammar för att motstå de två globala brottmoderna glidning och stjälpning. Frågan som behöver besvaras är om det finns eller kan finnas några kombinationer av brottmoder som borde beaktas vid dimensionering av dammar. 2009 antogs Eurokoderna och trädde i kraft 2011. Eurokoderna har ersatt BKR vid dimensionering av de flesta konstruktioner i Sverige. I Eurokod används partialkoefficienter för att garantera säkra konstruktioner. Syftet med denna rapport var att undersöka om dagens brottkriterium är tillräckliga för att beskriva hur dammar går till brott. Rapporten behandlar även möjligheten att övergå från att dimensionera dammar enligt RIDAS till att dimensionera enligt Eurokod. För att besvara detta genomfördes en litteraturstudie av rapporterade dammbrott. Dessutom genomfördes analytiska beräkningar för flera olika typer av dammar med varierande geometri och lastfall. Programmen CADAM och BRIGADE användes som ytterligare verktyg för att analysera brottmoderna. Enligt resultat från de analytiska beräkningarna tillsammans med FE-beräkningarna ansågs limit turning inträffa och genererade i högre grad en lägre säkerhetsfaktorer i jämförelse med stjälpning. Limit turning kan förklars som delvis stjälpande och inkluderar brott av bergmassan. Brottmodet är dock beroende av kvalitéten hos berget och det krävs undersökningar av grunden för att kunna göra en god uppskattning av dammens verkliga beteende. Sammanställningen av tidigare brott visade att nu gällande brottkriterier är lämpliga och troligtvis tillräckliga. Utmaningen är istället att säkerställa att konstruktionerna är korrekt utförda och därmed uppfyller dessa brottkriterier. En övergång till Eurokod tycks vara möjlig för de globala brottmoderna, dock är det väsentligt att partialkoefficienterna justeras för att uppnå resultat som överensstämmer med RIDAS, särskilt för stjälpning.
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Pierce, Ian. "Applying the Material Point Method to Identify Key Factors Controlling Runout of the Cadia Tailings Dam Failure of 2018." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/104218.
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This thesis examines the 2018 failure of the Northern Tailings Storage Facility at Cadia Valley Operations, located in New South Wales, Australia. First, the importance of examining and understanding failure mechanisms and post failure kinematics is described. Within which we understand that in the current state of affairs it is exceedingly difficult, or nigh impossible to perform without the use of large strain analyses, which have yet to permeate into the industry to a significant degree. Second, the initial construction and state of the dam just prior to failure is defined, with the materials and their properties laid out and discussed in depth as well as our means of modeling their behavior. Third, we validate and discuss our results of the base model of the dam based on key topographic features from initial and post-failure field measurements. After validation, we examine the influences of each of the different materials on the runout, comparing final topographies of different simulations with the actual final topography observed. This study was a valuable method of validating the Material Point Method as a means of modeling large deformations, as well as demonstrating its powerful applications towards catastrophic disaster prevention. The study validates and provides a greater understanding of the event of the Cadia Tailings Storage Facility Failure, and presents a framework of steps to perform similar examination on future tailings dams as a means of providing risk management in the event of failure.Master of Science
Tailings dams are structures integral to the life cycle of mining and mineral processing. After mining and the processing of mined materials, the leftover material, known as "tailings" are pumped and stored behind these structures, usually indefinitely. These structures are unique because they are usually expanded as additional storage space for these materials is required. Over the past several decades, the rate at which catastrophic or serious tailings dam failures occur out of failures has been on the rise. Because of this, it becomes necessary to better understand the failure and post-failure movements of the dam. This thesis presents one such failure, the Cadia Tailings Dam Failure of 2018, which is located in New South Wales, Australia. It applies the Material Point Method, a numerical method which allows for largestrain deformations, to examine the post-failure mechanism and interpret various influences by the different materials on the final runout. Because of this, the paper provides insights on the importance of understanding large strain analyses, discussing and presenting the incidents of the failure. The model used for reference is validated using topographic and field data taken after the failure, allowing for a comparison with future models which vary the geometry and material characteristics of the event. A procedural plan is proposed to apply to future analyses, allowing for the analysis to be applied to other events and tailings dam structures, for further insight on influences of variability and material properties on post-failure topography and geometry.
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Duque, Marta Alexandra Cardoso. "Reconstitution of the failure of the Fonte Santa mine tailings dam. Modelling of the dam breaching process." Master's thesis, FCT-UNL, 2011. http://hdl.handle.net/10362/6889.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em
Engenharia Civil Perfil de Estruturas e GeotecniaA 27 de Novembro de 2006 ocorreu a ruptura da barragem de rejeitados das minas de Fonte Santa, provavelmente devida a uma combinação de riscos nomeadamente, precipitação extrema ocorrida nos dias anteriores e eventual obstrução do descarregador de cheias. Uma primeira visita ao local, pouco após o acidente, mostrou que a barragem praticamente desapareceu por completo e que uma parcela de lamas depositadas na albufeira havia sido igualmente transportada para jusante. Numa outra visita de campo, no início de 2007, foi efectuado um levantamento dos danos ocorridos no vale a jusante com registo das alturas máximas do escoamento e caracterização das zonas de erosão e de deposição de material sólido. Nesta dissertação apresenta-se a reconstituição do acidente da ruptura da barragem de rejeitados das minas de Fonte Santa, incluindo uma descrição da brecha, do processo de ruptura e das consequências no vale a jusante, nomeadamente em termos de alturas máximas de escoamento e alterações morfológicas mais marcantes. A brecha resultante do galgamento do corpo da barragem foi simulada com recurso a um modelo numérico, sendo os dados da ruptura utilizados no processo de calibração e validação deste.
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Gebhart, Tristan Reyes. "POST-LIQUEFACTION RESIDUAL STRENGTH ASSESSMENT OF THE LAS PALMAS, CHILE TAILINGS FAILURE." DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1662.
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Assessment of post-liquefaction residual strength is needed for the development of empirically-based, predictive correlations for earthquake engineering design. Previous practice commonly assigned negligible strengths to liquefied materials for engineering analysis, producing overly-conservative designs. Increasingly available case history data, and improved analytical tools have allowed for more accurate and less overly-conservative estimation of soil residual strength, improving empirical predictive models. This study provides a new case history to the limited suite of (approximately 30) liquefaction failure case histories available for post-liquefaction in-situ strength predictive correlations.
This case history documents the Las Palmas gold mine tailings dam failure, resulting from seismic-induced liquefaction during the moment magnitude 8.8 February 27, 2010 Maule, Chile earthquake; the sixth largest since 1900. Forensic analysis provides reasonably well-constrained values of 1) back-calculated representative post-liquefaction residual strength, 2) representative penetration resistance, and 3) representative vertical effective stress along the suspected liquefied failure surface.
This study employs the incremental momentum method to incorporate momentum effects of a moving soil mass. The incremental momentum method requires a series of cross sections animating the geometry of failure progression from initiation to termination, converging on the observed final geometry. Using interpreted soil strength characteristics, an iterative procedure approximates the back-calculated value of post-liquefaction residual strength.
Findings of this case history plot well with existing empirical deterministic regression charts and are in general agreement with previous, related efforts. Results yield representative, well-constrained values of: 1) post-liquefaction residual strength ≈ 173 psf, 2) penetration resistance of N1,60,CS ≈ 5 and N1,60 ≈ 2.5, and 3) vertical effective stress ≈ 4,300 lb/ft2, or ≈ 2.0 atm.
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Iqbal, Ali. "Probability of Failure for Concrete Gravity Dams for Sliding Failure - Proposal to solution for the eleventh ICOLD Benchmark workshop." Thesis, KTH, Jord- och bergmekanik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-100538.
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Safety of dams can be evaluated based on the risk analysis methodologies that accounts for estimation of the risks associated to the dam-reservoir system. For this purpose it is important to estimate the probability of load events and probability of failure for several failure modes. The following thesis emphasises on estimation of the probability of one specific failure mode, i.e. “sliding failure” for a concrete gravity dam. The main idea behind this thesis was to analyse the estimation of the probability of sliding failure of an existing dam by obtaining the relationships among the different load events, factors of safety associated to those events and the probability of failure estimated using numerical simulation techniques together with different reliability methods. The analysed dam is taken from theme C of the eleventh ICOLD Benchmark workshop on numerical analysis of dams. The thesis covers the methodology for estimating the probability of failure of a given concrete gravity dam with five water levels, considering the sliding failure mode along the dam-foundation interface along with the estimation of factors of safety for each water level and with two different drainage conditions. First order second moment Taylor’s Series Approximation is being used as Level 2 reliability method and Monte Carlo simulation as Level 3 reliability method to estimate the probability of failure against sliding of the dam. Conclusions are drawn in the end by comparing the results obtained from factor of safety estimation and probability of failure for each water level and drainage condition, followed by suggestions for further research in the context of sliding stability of concrete dams.
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Trindade, Manoel Gustavo Neubarth. "Direito contratual como redutor das falhas de mercado." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/77180.
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No presente estudo, buscar-se-á investigar o direito contratual enquanto redutor das falhas de mercado, analisando de que forma essas falhas incidem sobre o fenômeno contratual, assim como de que modo as normas de direito contratual atuam sobre elas, buscando proporcionar maior eficiência econômica e bem-estar. Assim, inicialmente, tratar-se-á dos aspectos conceituais concernentes aos contratos e das realidades fáticas que lhe são subjacentes, de modo a diferenciá-los, além de analisar-se o papel do direito contratual nesse processo. Dando continuidade a essa tarefa, abordar-se-á a realidade falível dos sistemas de mercado, bem como de que forma as falhas de mercado atingem a eficiência negocial e operacional dos mercados. Por fim, analisar-se-á cada uma das espécies de falhas, quais sejam, a assimetria informacional, o poder de mercado, os custos de transação e as externalidades, ponderando de que forma o direito contratual pode debelar ou mitigar os efeitos nocivos que delas são decorrentes.The present study will seek to investigate the contractual law while reductor of market failures, analyzing how these failures affect the contractual phenomenon, as well as how the rules of contract law act on market failures, seeking provide greater economic efficiency and welfare. So, initially, it will treat the conceptual aspects pertaining to contracts and factual realities underlying it, in order to differentiate them, and analyzing the role of contract law in this process. Continuing this task will address the reality fallible of market systems and how the market failures affect the negotiation and operational efficiency of markets. Finally, it will analyze each species of failures, namely, informational asymmetry, market power, transaction costs and externalities, pondering how contract law can overcome or mitigate the harmful effects that of them are due.
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Malhotra, Kyle, and Ferena Salek. "An Inpatient Multidisciplinary Educational Approach to Reduce 30-day Heart Failure Readmissions." The University of Arizona, 2016. http://hdl.handle.net/10150/614003.
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Class of 2016 Abstract and ReportObjectives: An estimated 5.7 million Americans had heart failure (HF) in 2012 with an economic cost of $30.7 billion. By 2030 the prevalence of the disease is expected to increase by 46%. Centers for Medicare and Medicaid Services penalizes hospitals for 30-day readmissions. This study evaluated the effect of our multidisciplinary HF intervention on readmissions. Methods: This is a retrospective cohort study. Patients were identified from electronic inpatient admission records from January 1 to December 31, 2014. Patients who received any component of intervention were compared to patients who did not receive any intervention. Intervention included student pharmacist medication counselling, HF education, and post-discharge phone calls with Modified Morisky questionnaire. Age, sex, admission/discharge dates, readmission diagnosis, smoking status, ejection fraction, medications, and Charlson Comorbidity Index (CCI) conditions were collected. Results: A total of 221 patients with 249 discrete admissions were identified. No difference in age (p=0.42), sex (p=0.48), smoking status (p=0.10) existed between the groups. No difference in readmissions was found between patients receiving complete intervention and control (p=0.41) or patients receiving 1 or 2 intervention components and control (p=0.41). Patients with CCI score≥ 8 had greater risk of readmission compared to CCI scores 0-2 (OR 7.7, 95% CI 1.6-36.3, p=0.01). Conclusions: This analysis did not identify an intervention impact on 30-day readmissions in patients with HF; high CCI scores were associated with increased readmission risk. The intervention may be best targeted towards patients with high CCI scores as they have the highest readmission rate.
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Spence, K. J. "Investigation of flowslides from the failure of mine tailings' dams." Thesis, University of Sheffield, 1992. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285652.
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Fekadu, Robel Tekeste, and Sujata Kayastha. "Safety Assessment of Cracked Buttress Dams." Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284527.
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Most of the concrete buttress dams in Sweden were built from the 1950s till the1980s based on the traditional method of analyses. Those structures are reinforced and heavy in structure. Their height to thickness ratio being large makes them prone to crack during their lifespan. The presence of these cracks make the reinforcements used in the buttress dam susceptible to corrosion due to the water entering through the cracked areas. Therefore, studying the effect of cracks and corrosion regarding the safety of dams is important and should be carried out before the dams fail to function. However, only limited researches have been conducted to address these issues. The main goal of this project is to evaluate if the traditional method of analysis were sufficient to capture the failure modes of the dam before and after the occurrence of cracks and corrosion of the reinforcement. In the traditional method, the analytical stability calculations for the factor of safety of sliding and overturning are computed separately. However, in reality, those two failure modes do not occur separately but in combined mode. Therefore, to study this matter, two case studies were considered. In these studies, both finite element analysis (FEA) and analytical calculations were performed to investigate the failure modes. Moreover, this project assesses the influence of cracks and corrosion of reinforcements in the factor of safety. And, the software that was used to carry out the FE analyses were COMSOL and Abaqus. And alongside to FE software, MATLAB was used to carry out the analytical calculations. The results from the analyses showed that the combined failure modes in FE-analyses were the mode of failure of the buttress dams in all cases. Therefore, the analytical calculations were not sufficient to capture the failure modes. Furthermore, the reinforcements that were incorporated in the dam were observed to have a significant effect on the factor of safety depending on the patterns of the cracks. Similarly, the corrosion of the reinforcement had severe effects on the factor of safety based on the crack patterns. Based on the findings from the project, the combined failure mode from FE analysis the governing failure mode, and therefore, traditional analytical methods should be carried out to help evaluate those FE analyses but not to capture the actual failure modes. Besides, the incorporated reinforcements and their corrosion had notable influences on the safety factor of dams which should be investigated carefully.De flesta betonglamelldammar i Sverige byggdes under 1950 - 80-talet baserat påden traditionella analysmetoden. Dessa strukturer är armerade och tunga. Derashöjd-tjocklek förhållande är stor nog för att de ska vara benägna att spricka underderas livstid. Uppkomsten av dessa sprickor utsätter armeringen i lamelldammar förkorrosion på grund av att vattnet tränger in genom dessas sprickor. Därför är detytterst viktigt att studera effekter av sprickor och medföljande korrosion avseendedammsäkerhet och bör utföras innan dammarna är ur funktion. Trots vikten avdetta problem, har endast begränsade studier genmfört för att hantera dessa frågor.Huvudmålet med detta examensarbete är att utvärdera den traditionellaanalysmetodens kapacitet att fånga dammens brottillstånd före och efteruppkomsten av sprickor och armeringskorrosion. I den traditionella metoden utförsde analytiska stabilitetsberäkningar av säkerhetsfaktorn för glidning och stjälpningseparat. Men i verkligheten förekommer inte dessa två fenomen separat utan ikombinerat form. För att studera detta fenomen beaktades därför två fallstudier. Ibåda fallen utfördes finita element metod (FEM) och analytiska beräkningar föratt utvärdera brottillstånd. Dessutom utvärderas påverkan av sprickor ocharmeringskorrosion på säkerhetsfaktorn. Programvaran som användes för attutföra FE-analyserna var COMSOL och ABAQUS. Analytiska beräkningarutfördes i MATLAB.Resultaten från analyserna visade att ett kombinerat brottillstånd uppstod iFE-analyserna av lamelldammarna i samtliga studerade fall. Därmed är de utfördaanalytiska beräkningar inte tillräckliga för att fånga brottillståndet. Vidareobserverades att armeringar hade betydande inverkan på säkerhetsfaktornberoende på sprickmönstren. På liknande sätt hade armeringskorrosion signifikantinverkan på säkerhetsfaktorn beroende på sprickmönstren.Utifrån resultatet av FE-analyserna kan man konstatera att den kombineradebrottmoden var det avgörande brottillståndet, och därför bör traditionellaanalysmetoder utföras för att stödja utvärderingen av dessa FE-analyser men inteför att erhålla de faktiska brottillstånd. Dessutom, det kunde observeras attarmering och armeringskorrosion har betydande påverkan på säkerhetsfaktorn avdammar och bör undersökas noggrant.
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Chua, Merlyn. "Training for Advanced Practice Providers in a Heart Failure Unit." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/6187.
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Information from anecdotal interviews at a practicum site indicated a lack of training for advanced practice providers (APPs) in core competencies critical for effective practice in a heart failure (HF) unit. The goal of this project was to assess the APPs' verbal reports and develop HF unit-specific training for APPs. The practice-focused question examined whether unit-specific training for HF APPs improved knowledge and skills in HF management. The Johns Hopkins nursing evidence-based practice model and Knowles's adult learning theory were used to create a survey, a focus group, and a pre/posttest assessment of knowledge and skills gap. Descriptive and inferential statistics could be used to analyze pre/post survey data, and thematic analysis could be used to analyze focus group data. Assessment data could be used to develop a targeted HF program based on identified skill deficiencies. The implications of this project related to social change are the potential to increase APPs' knowledge, job engagement, and retention. The program could affect length of stay and 30-day readmission of patients in the HF unit.
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Aboelata, Maged A. "Conceptualization and Development of a Dam Break Life-Loss Estimation Model." DigitalCommons@USU, 2005. https://digitalcommons.usu.edu/etd/4540.
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Catastrophic events such as dam failures or severe floods are considered to be of low probability, although their consequences can be extremely high and might include loss of life. Earlier studies have linked circumstances surrounding historical darn failure events to actual loss of life and produced formulations using statistical analysis of these events. Shortcomings of these methods include the inability to adjust life-loss estimates based on the type of darn failure, global averaging of population at risk, and ignoring the dynamics of the evacuation process.
The main objective of this research is to develop a practical and improved life-loss estimation approach for use in dam safety risk assessment and emergency planning. The methodology is specifically formulated to overcome the limitations of previous. purely empirical, approaches. The approach takes into account the spatial and temporal distribution of flood water depth and velocity, fate of buildings, simulation of warning diffusion, and tracking the movement of people from their original location towards safe shelters.
The model created, called LlFESim, is designed to serve multiple function s. First, it can be used in a Deterministic Mode using best estimate inputs to obtain point estimates, or to test different policies for evacuation as well as different times of the day and for different dam breach flooding scenarios. Second, the Uncertainty Mode represents input and parameter uncertainties to provide estimates of life loss, and other variables relating to warning and evacuation effectiveness, as probability distributions. These distributions of life loss can be combined with estimates of the uncertainties in other risk assessment inputs, to obtain estimates of uncertainties in risk assessment results, including evaluations against tolerable risk guidelines.
Two communities were used to demonstrate the model performance. Deterministic Mode results display the various possible model outputs. Sensitivity analysis for the Deterministic Mode shows that the effect of warning issuance time is the dominant factor in the estimated life loss. However, other factors play an important role such as the time of day, effectiveness of the warning system, and shelter location. Uncertainty Mode results demonstrate the effect of uncertainties in model parameters and inputs on the model results.
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Fleshman, Mandie Swainston. "Laboratory Modeling of Critical Hydraulic Conditions for the Initiation of Piping." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1364.
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Seepage-related erosion is one of the predominant mechanisms responsible for incidents and failures of dams and levees. Current geotechnical engineering practice consists of comparing expected exit gradients with the critical gradient of the soil at the seepage exit point. The critical gradient is generally considered as the ratio of soil buoyant unit weight and the unit weight of water, suggesting that the critical gradient only depends on the void ratio and specific gravity of the solids. However, in the field and in research, it has been observed that piping can initiate at average gradients much lower than unity due to concentrations in flow and non-vertical exit faces. Therefore, there is a need for deeper understanding of the granular scale mechanisms of the piping erosion process. This thesis presents the results of a laboratory study to assess the effects that soil properties and exit face configurations have on the potential for initiation of piping and the piping mechanisms. By using a laboratory device designed and constructed specifically for this study, the critical gradients needed to initiate piping in a variety of sandy soils were measured to assess the effects that parameters such as gradation, grain size, and grain shape have on the critical gradients. The tests are also used to observe the grain scale mechanisms of piping erosion initiation. The ultimate goal of the study is to develop an empirical, but mechanism-based, grain-scale model that can take into account the effects of converging flows, non-horizontal exit faces, and soil properties while assessing the potential for piping erosion to occur.
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Eyegue-Sandy, Katherine. "Decreasing Thirty Days Hospital Readmission Rates of Adult Heart Failure Patients." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3767.
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Heart failure is a complex heart disease that incapacitates more than 5 million people, is associated with increasing healthcare cost, and remains the leading cause of admission in the United States. As the United States faces increasing financial burden related to readmission of heart failure patients within 30 days of discharge, many healthcare institutions are evaluating interventions to determine the most effective opportunities to improve systems, including nursing practice. The purpose of this doctoral project was to improve readmission rates within 30 days of discharge from an acute care facility through the development and implementation of a standardized, evidence-based, patient-centered discharge education toolkit using the Teach-Back method. Orem's self-care theory and the situation-specific theory of heart failure self-care were utilized as a theoretical framework to inform this doctoral project. The sources of evidence were obtained from the Get With The Guidelines-Heart Failure database and through a review of nursing and health-related databases. Descriptive statistics were used to compare the pre- and posteducation session readmission rates. The rate of readmissions occurring within thirty days of discharge pre- and post-educational session retrieved from the GWTG-Heart Failure database were 9.4% and 0.0% respectively. These results showed that this discharge toolkit reduced heart failure 30-days readmission rates. The limitations and strengths of this project will be used to guide further research on heart failure readmission and self-care management. This DNP project will promote positive social change for clinicians, who can use this discharge toolkit to improve self-management in adults with heart failure and thus decrease the costs related to readmission.
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Hayashida, Yoichi. "Evaluation of soundness and seismic behavior of long-term-use irrigation dams." Kyoto University, 2018. http://hdl.handle.net/2433/232155.
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Felippe, Carla Imaraya Meyer de. "INVESTIGAÇÃO DAS CAUSAS DO FRACASSO ESCOLAR NAS ESCOLAS PÚBLICAS DA ZONA URBANA DA CIDADE DE RIO GRANDE." Universidade Catolica de Pelotas, 2006. http://tede.ucpel.edu.br:8080/jspui/handle/tede/65.
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Previous issue date: 2006-01-09Abstract- The study examined the causes of school failure related to the child and his/her familiar environment, identifying the prevalence and diversity of problems that lead to failure in the initial grades. It involved parents, teachers and students, enabling the researcher to have an ample vision about the school-failure. Outline of the study was characterized by a cross-sectional study of cases and controls, at a school level. Children of first and second grade from public schools of the urban area from the city of Rio Grande- RS, Brazil participated in the study. The sample comprised 614 students (307 in each group), excluding the children with history of mental disorder and/or who have special needs. The groups were paired by the following criteria: being in the same classroom in 2002, have approximately same age, same gender and living in the same neighborhood. Analyses were conducted by chi-square test and multivariate conditional logistic regression. The analysed variables were related to the socioeconomic level, school performance, individual development and family characteristics. The studied variables which showed to be significant were: families with low income, low level of education of parents, difficulties in Reading Writing Arithmetics, low marks in Portuguese and/or Mathematics. The hypothesis that the school failure is associated with sociodemographic factors, familiar characteristics, as well as characteristics of the student was confirmed. We hope that the institutions in the city of Rio Grande will keep the data about failure in mind, taking some action to minimize it, considering all factors that are involved
Resumo- O estudo examinou as causas do fracasso escolar relacionadas com a própria criança e seu ambiente familiar, identificando a prevalência e a diversidade de problemas que levam à repetência nas séries iniciais. Envolveu pais, professores e alunos, possibilitando uma visão abrangente sobre o insucesso escolar. O delineamento caracterizouse como um estudo transversal de casos e de controles, com base escolar. Participaram crianças de 1ª e 2ª séries da rede pública do Ensino Fundamental da zona urbana da cidade 46 de Rio Grande- RS. A amostra constituiu-se de 614 alunos (307 para cada grupo), sendo excluídas crianças com história de doença mental e/ou portador de necessidades especiais. O grupos foram pareados pelos seguintes critérios: estar na mesma sala de aula em 2002, ter idade aproximadas, mesmo gênero e morar no mesmo bairro. Foram realizadas análises pelo teste do Qui-quadrado e análises multivariadas de regressão logística condicional. As variáveis analisadas foram: relacionadas ao nível sócioeconômico, as relacionadas ao desempenho escolar, ao desenvolvimento do sujeito e às características familiares. As variáveis estudadas que se mostraram significativas foram: famílias com baixa renda, pouca escolaridade dos pais, dificuldade em leitura escrita aritmética, notas baixas em Português e/ou em Matemática. Foi confirmada a hipótese de que fracasso escolar está associado a fatores sóciodemográficos, características familiares, além de características do próprio aluno. Esperamos que órgãos na cidade de Rio Grande considerem os dados sobre a repetência, tomando iniciativas no sentido de minimizá-la, considerando todos os fatores que a envolvem
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COSTA, VALTER M. "Análise das variáveis de entrada de uma rede neural usando teste de correlação e análise de correlaçao canônica." reponame:Repositório Institucional do IPEN, 2011. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10037.
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Mir, Riyaz Ahmad. "An experimental investigation into the seismic induced failure of moderately high concrete gravity dams." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239139.
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Lemos, Sérgio Pereira Pinto. "Avaliação do grau do dano das estruturas do subsolo de três edifícios situados na Região Metropolitana do Recife." Universidade Católica de Pernambuco, 2006. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=29.
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Procurando conhecer o grau de deterioração precoce das estruturas de concreto armado dos edifícios residenciais da Região Metropolitana da Cidade do Recife, Estado de Pernambuco, este trabalho visa, utilizando um método de quantificação dos danos e o uso de ensaios, avaliar as patologias das estruturas estudadas. Estudou-se três edifícios residenciais (ER), com semelhante padrão de construção, idades construtivas aproximadas e inseridos em diferentes classes de agressividade ambiental. Foi realizada inspeção visual e ensaios em amostras dos pilares, vigas, lajes e reservatório inferior do subsolo dos três edifícios. Após análise dos três edifícios, verificou-se que o caso ER 1, localizado em classe ambiental de agressividade forte (III), a mais agredida pelo meio ambiente, e o estudo de caso ER 2, localizado a uma distância significativa da orla marinha em Classe de Agressividade Ambiental II, apresentaram grau de deterioração media (GD) de 36,98 e 31,23 respectivamente, com recomendação para inspeção periódica e intervenção a médio prazo. Já o estudo de caso ER 3, que está localizado dentro da uma classe de agressividade forte (III), em orla marinha, porém com barreiras de proteção que evitam a incidência direta da névoa salina, encontra-se com alto grau de deterioração (GD = 103,94), sugerindo uma intervenção imediata com riscos de colapsoThis work aims to evaluate the pathology of residential buildings structures located at the Metropolitan Region of Recife, Brazil using the quantification of damages to measure the degree of early deterioration of reinforced concrete. Three residential buildings (RB) with similar construction standards were studied. All buildings have approximate age and are inserted into environmental aggressiveness distinct. A visual inspection took place as well as a laboratorial sample analysis of their pillars, beams and underground water reservatories. It was verified that the RB1 case, located at a high environmental aggressiveness class (III), and the RB2 case, located significatively far from the sea and classified with a moderate environmental aggressiveness class (II), both presented a medium degree of deterioration (GDE). For both buildings it is suggested a periodic inspection recommendation and a medium term intervention (GD 1 = 36,98 ; GD 2 = 31,23). The third case (RB3), located at a high environmental aggressiveness class (III) and seafront with protection barriers, presented a high degree of deterioration (GD 3=103,94). It is suggested for RB3 an immediate intervention with collapse risks
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Enzell, Jonas, and Markus Tollsten. "Thermal cracking of a concrete arch dam due to seasonal temperature variations." Thesis, KTH, Betongbyggnad, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209839.
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Concrete dams located in northern regions are exposed to large seasonal temperature variations. These seasonal temperature variations have resulted in cracking in thin concrete dams. Continuous monitoring and evaluation of existing dams are important to increase the knowledge about massive concrete structures and to ensure dam safety. The aim of this degree project is to increase the knowledge about how cracking occurs in concrete dams and how it affects the dam safety. This was achieved by simulating the development of cracks in a concrete arch dam exposed to seasonal temperature variations using finite element analysis (FEA). The accuracy of the model was evaluated by comparing the results with measurements from a Swedish concrete arch dam. Finally, effect of cracks and temperature on the dam safety was investigated. FEA was used to predict the crack pattern and displacements in the arch dam. The analyses were performed both with linear elastic and nonlinear material behavior. Two models were analyzed, in one model the dam was considered to be a homogeneous arch, the other model included contraction joints. The cracking was simulated using temperature envelopes from the location of the Swedish arch dam. To evaluate the displacements in the arch, further analyses were carried out, where the cracked arch dam was exposed to the actual temperature variations at the location. The results were compared to the crack pattern and measurements of displacements of the Swedish arch dam. To investigate the effects from the cracking on the safety of the dam, a progressive failure analyses performed. The results show that the downstream face of the arch cracked under hydrostatic pressure. The cracks propagated further during winter when the temperature load was applied. The resulting crack pattern corresponded well with the survey of the cracks from the Swedish arch dam. The FE-models with nonlinear material developed a horizontal plastic hinge due to excessive cracking in a region halfway down from the crest. The plastic hinge affected the shape of the deflected arch. The magnitude of the displacements and the shape of the deflected arch was captured with the nonlinear models. A safety factor of 3 for internal structural failure in the arch was found in the failure analyses. The safety factor of the arch only decreased slightly due to the cracking. During a cold winter, the safety factor decreased to 2.5.Betongdammar belägna i nordliga klimat blir utsatta för stora säsongsburna temperaturvariationer. Dessa temperaturvariationer har orsakat sprickbildning i tunna betongdammar. Kontinuerlig övervakning och utvärdering av befintliga dammar är viktigt för att öka kunskapen om massiva betongkonstruktioner och för att säkerställa dammsäkerheten. Syftet med det här examensarbetet är att öka kunskapen om hur sprickor uppstår i valvdammar samt hur de påverkar anläggningens säkerhet. Målet är att med finit elementanalys (FEA) analysera uppsprickningen av betongen i en valvdamm som påverkas av säsongsburna temperaturvariationer. Tillförlitligheten i modellen utvärderas genom att jämföra med mätningar från en svensk valvdamm av liknande dimensioner. Slutligen utvärderas hur dammens säkerhet påverkas av sprickbildningen. FE-analys användes för att förutsäga sprickmönstret och förskjutningarna i valvdammen. Analyserna utfördes både med linjärelastiskt och icke-linjärt materialbeteende. Två modeller användes i analysen, i ena modellen betraktades dammen som homogen och i den andra inkluderades gjutfogar. Sprickmönstret simulerades med temperaturcykler baserade på extremtemperaturer tagna intill den svenska valvdammen. För att utvärdera förskjutningarna i dammen gjordes vidare analyser där den spruckna dammen utsattes för temperaturvariationer uppmätta från samma plasts. Resultaten från analysen jämfördes med mätningar av förskjutningar och kartering av sprickor från den svenska valvdammen. För att undersöka hur säkerheten påverkades av sprickbildningen utfördes progressiv brottanalys. Resultaten visar att dammen spricker på nedströmssidan när den utsätts för vattentryck. Sprickorna fortplantas under vintern när temperaturlasten appliceras. Sprickmönstret stämmer överens med kartering av den verkliga dammen. FE-modellerna med icke-linjärt materialbeteende utvecklade en plastisk led längs horisontella sprickor halvvägs ner från krönet. Den plastiska leden påverkade dammens utböjda form. Förskjutningarna och dammens utböjda form i de ickelinjära modellerna stämmer väl överens med de uppmätta förskjutningarna. Vid brottanalysen var säkerhetsfaktorn mot materialbrott i dammen 3. Säkerhetsfaktorn minskade något till följd av sprickorna. Under en kall vinter sjönk säkerhetsfaktorn till 2,5.
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Roscani, Meliza Goi [UNESP]. "Evolução das modificações morfo-funcionais cardíacas no processo de adaptação crônica à insuficiência aórtica aguda experimental em ratos." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/102643.
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roscani_mg_dr_botfm.pdf: 1793815 bytes, checksum: ef58e271a6e22be8d19da25e6d3d13c8 (MD5)A adaptação cardíaca à insuficiência aórtica resulta em hipertrofia excêntrica seguida de disfunção ventricular e insuficiência cardíaca. A evolução desse processo ainda não é bem compreendida. Avaliar a adaptação cardíaca à insuficiência aórtica aguda experimental por meio de ecocardiografia, identificar os marcadores anatâmicos de transição da hipertrofia excêntrica compensada para a fase descompensada e verificar se existe associação entre marcadores anatâmicos e de disfunção ventricular e fibrose miocárdica. Estudo experimental com 35 ratos Wistar machos, 23 animais submetidos à insuficiência aórtica aguda (grupo IAO) e 12 animais a procedimento simulado (Grupo Controle). Todos os animais foram seguidos com ecocardiogramas seriados com 1, 4, 8 e 16 semanas. No término do protocolo, foi realizada mortometria do tecido cardíaco. A análise estatística foi efetuada por meio do teste t de Student, Mann-Whitney, ANOVA de medidas repetidas, Modelo de Regressão Longitudinal (GEE) e Modelo de Regressão Linear simples e múltipla. Em todos os casos, o nível de significância adotado foi p
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Winiawer, José Eduardo Beltrão. "Análise de estabilidade de túneis escavados em meios rochosos : aplicação ao caso do colapso do túnel Estação Pinheiros." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/61064.
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Uma maneira de analisar a estabilidade de túneis escavados em maciços rochosos fraturados é a baseada na teoria da análise limite utilizando um critério de resistência macroscópico desenvolvido a partir da teoria de homogeneização. Este trabalho primeiramente descreve o comportamento mecânico dos constituintes do maciço rochoso fraturado e os métodos usuais de análise. Posteriormente é descrita a teoria da análise limite e da homogeneização em análise limite, utilizando estas teorias é apresentado o critério de resistência macroscópico para maciços rochosos fraturados em estado plano de deformações desenvolvido por Fréard (2000) e desenvolvido um critério de resistência macroscópico para maciços rochosos fraturados para o caso tridimensional. A partir destes critérios aplicaram-se mecanismos de ruptura para se encontrar limites superiores da função de estabilidade. Assim permitindo a análise da previsibilidade do colapso do túnel estação Pinheiros do metrô de São Paulo o qual os resultados apresentavam a possibilidade de prever o colapso.One way of analyze the stability of tunnels excavated at fractured rock masses is based on the theory of yield design using a macroscopic strength criterion developed from the theory of homogenization. This dissertation first describes the mechanical behavior of the fractured rock mass constituents and the usual methods of analysis. Later is described the yield design theory and the theory of homogenization applied to the yield design using these theories is presented macroscopic strength criterion for fractured rock masses in a state plan developed by Fréard (2000) and developed a macroscopic strength criterion for rock masses fractured to the three-dimensional case. Based on these criteria were applied failure mechanisms to meet the upper bounding of the stability function. So it’s possible to analyze the predictability of the collapse of the tunnel-station Pinheiros of the Sao Paulo subway which the results showed the possibility of predicting the collapse.
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Rato, João Carlos Mourão. "Gestão da manutenção da frota das UQE-S2300." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10119.
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Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão IndustrialA gestão da manutenção ferroviária apresenta-se actualmente e mais do que nunca como uma actividade estratégica para o desempenho eficaz e eficiente das organizações, possibilitando a estas benefícios de confiança, flexibilidade e redução de custos, representativos por sua vez no conforto, segurança e rapidez do serviço prestado ao utilizador. Na presente dissertação é apresentada uma análise de fiabilidade e gestão da manutenção aplicada a uma frota de 42 automotoras UQE-S2300 pertencentes à CP, que por sua vez se encontra à responsabilidade da EMEF no que respeita a operações de manutenção. Através da investigação prática pretende-se avaliar numa primeira fase e em contexto de sistema reparável a tendência das automotoras, de forma individual e global, em termos de fiabilidade, recorrendo-se desse modo a conceitos de processos estocásticos pontuais e à estatística do teste de Laplace. Para isso, recorreu-se a registos históricos das avarias de material e manutenção, conducentes a um determinado período de tempo. A identificação dos sistemas mais críticos da frota de automotoras, isto é, aqueles que apresentam um maior risco de falha, são um outro objectivo do presente estudo, tendo-se recorrido nesse sentido ao Princípio de Pareto. No que respeita a indicadores de desempenho, apresenta-se nesta primeira análise uma caracterização do comportamento médio da frota com base no indicador MTBF (Mean Time Between Failures), perspectivando um cenário de comparação para a segunda fase do estudo. Nesta, pretende-se analisar o benefício obtido em termos de incremento provocado no MTBF médio da frota, resultante da implementação do que se julgam ser as melhores soluções práticas para cada um dos sistemas críticos previamente identificados.
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Roscani, Meliza Goi. "Evolução das modificações morfo-funcionais cardíacas no processo de adaptação crônica à insuficiência aórtica aguda experimental em ratos /." Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/102643.
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Resumo: A adaptação cardíaca à insuficiência aórtica resulta em hipertrofia excêntrica seguida de disfunção ventricular e insuficiência cardíaca. A evolução desse processo ainda não é bem compreendida. Avaliar a adaptação cardíaca à insuficiência aórtica aguda experimental por meio de ecocardiografia, identificar os marcadores anatâmicos de transição da hipertrofia excêntrica compensada para a fase descompensada e verificar se existe associação entre marcadores anatâmicos e de disfunção ventricular e fibrose miocárdica. Estudo experimental com 35 ratos Wistar machos, 23 animais submetidos à insuficiência aórtica aguda (grupo IAO) e 12 animais a procedimento simulado (Grupo Controle). Todos os animais foram seguidos com ecocardiogramas seriados com 1, 4, 8 e 16 semanas. No término do protocolo, foi realizada mortometria do tecido cardíaco. A análise estatística foi efetuada por meio do teste "t" de Student, Mann-Whitney, ANOVA de medidas repetidas, Modelo de Regressão Longitudinal (GEE) e Modelo de Regressão Linear simples e múltipla. Em todos os casos, o nível de significância adotado foi pOrientador: Beatriz Bojiakian Matsubara
Coorientador: Luiz Shiguero Matsubara
Banca: João Carlos Hueb
Banca: Marcia Kiyomi Koike
Banca: Orlando Campos Filho
Banca: Valdir Ambrósio Moisés
Doutor
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Rebelo, Daniela Filipa Barrela. "Caracterização das infeções por Leptospira spp. em cães internados na Unidade de Isolamento e Contenção Biológica do Hospital Escolar da FMV-ULisboa no período de 2013-2019." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2021. http://hdl.handle.net/10400.5/21169.
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Dissertação de Mestrado Integrado em Medicina VeterináriaOs objetivos deste estudo consistiram em identificar possíveis fatores de risco, indicadores de prognóstico e de fatores que pareceram afetar o tempo de hospitalização, através da descrição epidemiológica, dos métodos de diagnóstico, da terapêutica, e das alterações clínicas, laboratoriais e imagiológicas, em cães positivos a leptospirose e internados na Unidade de Isolamento e Contenção Biológica do Hospital Escolar (UICB). Foram consultados os historiais médicos de 150 cães, com sintomatologia compatível com leptospirose, dos quais 55 eram positivos a leptospirose e os restantes 95 eram negativos, estando todos eles hospitalizados na UICB, de dezembro de 2013 a dezembro de 2019. A maioria dos cães foram diagnosticados a partir da serologia IgM (96,4%), e em nenhum dos casos foi realizado o MAT. Os sinais clínicos mais frequentes foram: o vómito (72,7%), a anorexia (50,9%), a diarreia (40,0%) e a hematúria (40,0%). As alterações analíticas mais frequentes no hemograma e bioquímicas foram: o aumento da AST (100%), o aumento da bilirrubina total (81,8%), o aumento da ureia (70,6%) e da creatinina (69,2%), a leucocitose com neutrofilia (68,0%), o aumento da ALT (55,1%) e a trombocitopenia (51,3%). Relativamente ao ionograma e urianálise, as principais alterações foram: a proteinúria (94,7%), a hematúria (73,7%), a hipocloremia (63,2%) e a hiponatremia (52,6%). Na ecografia abdominal, verificaram-se com maior frequência: a hepatomegália (47,2%), a hipoecogenicidade hepática (38,9%), a hiperecogenicidade do córtex renal (25,0%), a esplenomegália (25,0%), as lamas biliares (22,2%) e a perda da transição cortico-medular (16,7%). Na radiografia torácica, verificou-se na maioria dos casos um padrão intersticial não estruturado (27,8%) e um padrão interstício-alveolar (11,1%). Os antibióticos mais utilizados foram a ampicilina (69,1%) e a doxiciclina (65,5%), e verificou-se uma taxa de sobrevivência de 50,9%. Concluiu-se que os fatores de risco para a ocorrência de leptospirose, foram o facto de os cães serem adultos (entre os 2 e os 7 anos) e a ocorrência de uma maior precipitação (mais casos no inverno), e como fatores de proteção as cadelas estarem esterilizadas, os cães apresentarem uma idade igual ou superior a 8 anos e uma menor precipitação (menos casos no verão). Verificou-se um pior prognóstico em cães: seniores, hipotérmicos, oligoanúricos e com a ureia e/ou a creatinina aumentadas. Apenas a neutrofilia afetou o tempo para a ocorrência de alta (duração da hospitalização).
ABSTRACT - Characterization of infections by Leptospira spp. in dogs admitted to the Biological Containment and Isolation Unit of the Teaching Hospital of FMV-ULisboa in the period 2013-2019 - The objectives of this study were to identify possible risk factors, prognostic indicators, and factors that seemed to affect the length of hospital stay, through the epidemiological description, the diagnostic methods, the therapy, and the clinical, laboratory and imaging changes, in dogs positive for leptospirosis and admitted to the Biological Containment and Isolation Unit of the Teaching Hospital (BCIU). The medical histories of 150 dogs were consulted, with symptoms compatible with leptospirosis, of which 55 were positive for leptospirosis, and the remaining 95 were negative, all of whom were hospitalized at BCIU, from December 2013 to December 2019. Most dogs were diagnosed using IgM serology (96.4%) and MAT was not performed in any of the cases. The most frequent clinical signs were: vomiting (72.7%), anorexia (50.9%), diarrhea (40.0%) and hematuria (40.0%). The most frequent analytical changes in the blood count and biochemistry were: increased AST (100%), increased total bilirubin (81.8%), increase in urea (70.6%) and creatinine (69.2%), leukocytosis with neutrophilia (68.0%), increased ALT (55.1%) and thrombocytopenia (51.3%). Regarding ionogram and urinalysis, the main changes were: proteinuria (94.7%), hematuria (73.7%), hypochloremia (63.2%) and hyponatremia (52.6%). Abdominal ultrasound showed more frequently: hepatomegaly (47.2%), hepatic hypoechogenicity (38.9%), renal cortex hyperechogenicity (25.0%), splenomegaly (25.0%), bile sludge (22.2%) and the loss of the cortico-medullary transition (16.7%). In chest radiography, in most cases there was an unstructured interstitial pattern (27.8%) and an interstitial-alveolar pattern (11.1%). The most widely used antibiotics were ampicillin (69.1%) and doxycycline (65.5%) and a survival rate of 50.9% was verified. It was concluded that the risk factors for the occurrence of leptospirosis were the fact that the dogs are adults (between 2 and 7 years old) and the occurrence of greater precipitation (more cases in winter), and as factors of protection females are sterilized, dogs are 8 years old or older, and less precipitation (less cases in summer). There was a worse prognosis in dogs: seniors, hypothermic, oligoanuric, and with increased urea and / or creatinine. Only neutrophilia affected the time to discharge (duration of hospitalization).
N/A
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Oelbe, geb Wagner Miriam Svenja [Verfasser]. "LIMP2-Defizienz und das Action Myoclonus and Renal Failure (AMRF) Syndrom / Miriam Svenja Oelbe, geb. Wagner." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/1037109430/34.
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Louro, Marta Sofia Duarte. "Análise das start-ups informáticas em Portugal: 1990 a 2005." Master's thesis, Instituto Superior de Economia e Gestão, 2009. http://hdl.handle.net/10400.5/1145.
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Mestrado em Ciências EmpresariaisO objectivo deste trabalho de pesquisa é apresentar os resultados de um estudo exploratório sobre diversas variáveis organizacionais de todas as das start-ups informáticas (seguindo a classificação portuguesa das actividades económicas vigentes - CAE 72 - actividades informáticas e conexas) nascidas em Portugal, entre 1990 e 2005. A investigação considerou as variáveis capital inicial, dimensão inicial, volume inicial de vendas e área geográfica. A investigação foi realizada com base em informação relativa a 3115 empresas criadas durante o referido período. Após a classificação das empresas em dois grupos - aquelas que obtiveram sucesso e as de insucesso - analisámos os seus diferentes perfis, testamos estatisticamente a sua diferença e confrontamos os resultados com a literatura. No final, apresentamos as conclusões do trabalho, bem como as suas limitações e deixamos pistas para investigação futura.
The objective of this research work is to report the findings of an exploratory study on several organizational variables from all IT Portuguese entrepreneurial start-ups founded between 1990 and 2005. This study covers the following organizational variables: initial capital, initial dimension, initial sales level and geographical location. This research work was based upon data related to 3115 start-ups born in Portugal within the time frame. After classifying the start-ups into two groups - successful ones and unsuccessful ones - we have analyzed their profiles, we have tested their differences and we confronted results to previous literature. In the end of this study we present its conclusions, as well as, its limitations and we provide future research tips.
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Liu, Zhenzhen. "Hydro-mechanical analysis of breach processes due to levee failure." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4726/document.
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La rupture des barrages et des digues en terre est susceptible d’avoir des conséquences importantes en aval et dans les zones protégées. Nous avons mené une analyse hydro-mécanique de la formation et du développement de brèche destinée à améliorer la précision des approches actuelles. Dans le cas de l’érosion interne, un modèle d’agrandissement de conduit a été proposé pour modéliser la rupture des digues et barrages en terre par écoulement concentré. Ce modèle tient compte de l’érosion du sol par un écoulement de conduit turbulent. En ce qui concerne l’élargissement de la brèche, un modèle simple d’estimation de la longueur critique d’afouillement par “headcut” est proposé, fonction de la résistance du sol à la traction. Ce modèle est en bon accord avec les résultats numériques obtenus par équilibre limite. Un modèle simplifé pour la contrainte latérale sur les parois de la brèche a ensuite été proposé. Ce modèle tient compte des écoulements secondaires. Il montre que la contrainte latérale peut être plus grande que la contrainte de fond, suivant la situation. Finalement, une expérimentation de grande dimension de rupture de barrage par erosion de conduit a été modélisée avec le modèle d’érosion de conduit proposé, et quelques composantes des modèles d’élargissement de brèche proposés. L’élargissement de la brèche par paliers a été reproduite au début du processus. Les perspectives de validation et d'application des modèles proposés sont discutéesThe failure of embankment dams and levees can have serious consequence in floodplains. Hydro-mechanical analyses of the breach processes were conducted to develop the accurate estimation of the failure of embankment dams and levees. Considering the internal erosion process, a pipe enlargement model was proposed to simulate the failure of embankment dams and levees by concentrated leak erosion. In this model, the turbulent pipe flow with erosion mechanism was employed as well as the soil erosion law. Considering the breach enlargement process, a simple headcut migration model based on the soil tensile strength was presented to simulate the critical length of the headcut. Good agreements were obtained by comparing with the limit equilibrium numerical model. A simple model was eventually proposed to simulate the lateral shear stress on the breach sides, accounting for the secondary flow. The lateral shear stress can be greater than the bottom shear stress, depending on the situation. . Finally, a large-scale test of dam failure was simulated by using the pipe enlargement and some components of the breach widening models proposed. The simulation of the pipe enlargement process had good agreement with the measured data. Both of the pipe diameter and the discharge flow were well simulated. The stepwise enlargement of the breach width was also well simulated at the beginning of the breach widening process. Validation and application prospects of the proposed models are discussed
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Pedro, Beatriz de Castro Silva Miranda. "Impacto das competências de marketing no sucesso (insucesso) das Startups." Master's thesis, Instituto Superior de Economia e Gestão, 2019. http://hdl.handle.net/10400.5/19561.
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Mestrado em Gestão e Estratégia IndustrialApesar da crescente tendência para o aparecimento de startups nos mercados, a taxa de sucesso das mesmas permanece reduzida. Assim sendo, torna-se necessário perceber o motivo pelo qual esta tendência está, muitas vezes, condenada ao insucesso. Posto isto, o marketing foi identificado como um dos principais motivos pelos quais as startups não sobrevivem. Assim sendo, o propósito deste estudo é analisar o impacto das competências de marketing nas startups uma vez que, ao identificar os aspetos que levam ao seu sucesso, é possível concluir como é que a má exploração das competências de marketing podem conduzir a startup a falhar. Como tal foi conduzido um estudo qualitativo, com recurso a entrevistas semiestruturadas, a 10 startups portuguesas de modo a conseguir alinhar as proposições desenvolvidas com a revisão de literatura efetuada. Os resultados obtidos permitiram confirmar que a exploração correta das competências de marketing, tanto estratégicas como operacionais, é um dos motivos que leva à continuidade das startups, o que significa, ao mesmo tempo, que um dos principais motivos pelos quais estas podem falhar é a utilização inadequada das mesmas. As competências de marketing estão associadas à continuidade de uma startup, e embora não sejam as únicas, têm um peso determinante. Torna-se, por isso, essencial que as startups desenvolvam estas competências para que se mantenham vivas.
Despite the growing trend towards the emergence of startups in the markets, their success rate remains quite low. Therefore, it's necessary to understand the reasons why the startups are often condemned to failure. Marketing has been identified as one of the main reasons why startups do not survive. Consequently, the purpose of this study is to analyze the impact of marketing competences on the success of startups since, by identifying the aspects that lead to their success, it's possible to conclude how the poor exploration of marketing competences can lead to your failure. As such, a qualitative study was conducted, using semi-structured interviews, to 10 Portuguese startups in order to align the propositions developed by the literature. The results obtained allowed us to confirm that the correct exploration of marketing competences, both strategic and operational, are one of the reasons that leads to the continuity of startups. This means, at the same time, that one of the main reasons why these failures happen are the inadequate use of these competences. Marketing competences are associated with the continuity of a startup, and even though they are not the only ones, they have a "decisive weight". It is therefore essential that startups develop these competences in order to promote their sustainability.
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Štulír, Vojtěch. "Návrh a realizace systému pro maskování výpadku dispečerského PC zálohováním dat získaných z váhy TAMRON." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237185.
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In the productive operation any kind of plant is undesirable due to failure of system that all production has been stopped. Therefore, different security and backup devices that covered those failures are being developed and used. This thesis describes vulnerabilities in the real operation which are important for treatment and reduce the risk of failure in the whole production. Here is analyzed problem dispatching computer failure and its solution using a module for covering failure. The function of module consists in backup during failure, their sending and treating them after system failure removal. Gradually described, there is an analysis of the system and place the module into their architecture. After all details follow description of module development from design through implementation to deployment and testing in reality.
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Antunes, Nuno Emanuel Baptista. "O endividamento das famílias portuguesas em crédito à habitação : análise do período 2000 a 2010." Master's thesis, Instituto Superior de Economia e Gestão, 2013. http://hdl.handle.net/10400.5/11429.
Full textAbstract:
Mestrado em Economia Monetária e FinanceiraO estudo do endividamento das famílias com base em informação socioeconómica e demográfica é de particular relevância no momento actual, em que coexiste uma crise económica grave de elevado nível de endividamento. A existência simultânea destes dois aspectos (crise económica e dívida) faz olhar com alguma preocupação para a capacidade das famílias honrarem os seus compromissos financeiros. Neste trabalho pretende-se traçar uma relação entre o endividamento e as características das famílias, fundamentando teórica e empiricamente com o objectivo de determinar situações de maior vulnerabilidade. Utilizaram-se os dados de dois inquéritos às famílias, o Inquérito aos Orçamentos Familiares (IOF), realizado no ano 2000 e o Inquérito às Despesas das Famílias (IDEF), realizado no segundo trimestre de 2010. De acordo com os resultados obtidos, as famílias que apresentam 1 elemento no agregado familiar, onde o seu representante pertence a um maior escalão de rendimento, e que concluiu um nível de ensino elevado tem uma probabilidade significativamente maior de obter crédito à habitação, em 2010. Por outro lado, observaram-se famílias com 5 ou mais elementos no agregado familiar, em que o seu representante pertence ao segundo escalão de rendimento, que não tem qualquer nível de educação, reformado e solteiro, representa o perfil de representante com uma probabilidade significativamente menor de ter crédito à habitação.
The study of household debt based on demographic and socio-economic information is of particular relevance at the present time, due to the coexistence of a severe economic downturn of high indebtedness. The simultaneous existence of these two aspects (economic crisis and debt) makes us regard families ability to fulfill their financial commitments with concern. This paper intends to draw a relationship between indebtedness and household characteristics, based on theoretical and empirical data in order to determine situations of greater vulnerability. Data from two household surveys was used, the Household Budget Survey (HBS) conducted in 2000 and the Household Expenditure Survey (IDEF) held in the second quarter of 2010. According to the results, families with a household member who belongs to a higher level of income and concluded a higher level of education are significantly more likely to obtain a housing loan in 2010. On the other hand, families were found composed of 5 or more household members, in which the agent belonged to the second tier of income, had no level of education, was retired and single, which represented a profile with a significantly lower probability of obtaining a housing loan.
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Galvão, Siha Fernandez Valente. "Insuficiência renal aguda no Hospital das Clínicas da Faculdade de Medicina de Botucatu - UNESP : descrição da população e análise dos fatores de risco associados a mortalidade /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/95183.
Full textAbstract:
Orientador: André Luis BalbiBanca: Jacqueline Teixeira Caramori
Banca: Pedro Alejandro Gordan
Resumo: A Insuficiência Renal Aguda apresenta uma alta incidência em pacientes internados em hospitais terciários, principalmente em Unidades de Terapia Intensiva, estando associada a elevada mortalidade. Este trabalho tem como objetivos descrever a população de pacientes internados no Hospital das Clínicas de Faculdade de Medicina de Botucatu - UNESP com diagnóstico de Insuficiência Renal Aguda atendidos pelo Grupo de Interconsultas do Serviço de Nefrologia e avaliar os fatores de risco associados ao óbito nestes pacientes. Foram acompanhados 946 pacientes no período de abril de 2002 a dezembro de 2006, todos maiores de 12 anos, com diagnóstico de Necrose Tubular Aguda e internados nas diferentes enfermarias e Unidades de Terapia Intensiva do Hospital das Clínicas, exceto na Pediatria e Nefrologia. Insuficiência Renal Aguda foi definida como um aumento de creatinina sérica de pelo menos 30% de seu valor basal em período mínimo de 48 horas. A média de idade foi de 61,8 ± 16,7 anos, com predomínio do sexo masculino (61,9%). Pacientes provenientes de enfermarias clínicas foram mais freqüentes (62,1%), sendo que 15,9% estavam internados na cardiologia e 15,2% na clínica médica geral, enquanto 13,3% estavam internados na enfermaria de gastroenterologia cirúrgica. 46,1% estavam internados em Unidades de Terapia Intensiva e a sepse esteve presente em 9,7% dos casos. Isquemia (51,2%) foi a etiologia mais freqüente e o tempo de acompanhamento nefrológico apresentou mediana de 7,5 dias, com intervalo interquartílico de 4 a 14 dias.
Abstract: Acute Renal Failure (ARF) present a high incidence in critically ill patients taken into tertiary care hospitais, mostly in the Intensive Care Unit (ICU) patients, were also associate with great mortality rate. The objective of this work was to describe the population of patients hospitalized in the School Medicine, Botucatu- UNESP with diagnosis of ARF, attended by Group of - Interconsults of Service Nephrology and to evaluate the risk factors associate with death in this patients. This was a cohort study which evaluated 946 patients with ARF, from April 2002 to December 2006, was included patients older than 12 years, with diagnosis of ARF due to Acute Tubular Necrosis (ATN) and hospitalized in wards and ICU of HC- FMBUNESP (except in the Pediatrics and Nephroloy wards). ARF was defined as serum creatinine at least 30% above basal value from 48 hours at minimum. The average of age was 61,8 ± 16,7 years, with predominantly masculine gender (61,9%). 15,9% were hospitalized in the cardiology and 15,2% in the clinical medical, while 13,3% were hospitalized in the gastroenterology surgical ward. 46,1% of patients were hospitalized in ICU and the sepsis was present in 9,7% of the cases. Ischemia was the etiology more frequent (51,2%) and the time of accompaniment nephrologic presented an median of 7,5 days (4 - 14).
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