Dissertations / Theses: 'Fast production'

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Danje, Stephen. "Fast pyrolysis of corn residues for energy production." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17822.

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Thesis (MScEng)--Stellenbosch University, 2011. ENGLISH ABSTRACT: Increasing oil prices along with the climate change threat have forced governments, society and the energy sector to consider alternative fuels. Biofuel presents itself as a suitable replacement and has received much attention over recent years. Thermochemical conversion processes such as pyrolysis is a topic of interest for conversion of cheap agricultural wastes into clean energy and valuable products. Fast pyrolysis of biomass is one of the promising technologies for converting biomass into liquid fuels and regarded as a promising feedstock to replace petroleum fuels. Corn residues, corn cob and corn stover, are some of the largest agricultural waste types in South Africa amounting to 8 900 thousand metric tonnes annually (1.7% of world corn production) (Nation Master, 2005). This study looked at the pyrolysis kinetics, the characterisation and quality of by-products from fast pyrolysis of the corn residues and the upgrading of bio-oil. The first objective was to characterise the physical and chemical properties of corn residues in order to determine the suitability of these feedstocks for pyrolytic purposes. Secondly, a study was carried out to obtain the reaction kinetic information and to characterise the behaviour of corn residues during thermal decomposition. The knowledge of biomass pyrolysis kinetics is of importance in the design and optimisation of pyrolytic reactors. Fast pyrolysis experiments were carried out in 2 different reactors: a Lurgi twin screw reactor and a bubbling fluidised bed reactor. The product yields and quality were compared for different types of reactors and biomasses. Finally, a preliminary study on the upgrading of bio-oil to remove the excess water and organics inorder to improve the quality of this liquid fuel was performed. Corn residues biomass are potential thermochemical feedstocks, with the following properties (carbon 50.2 wt. %, hydrogen 5.9 wt. % and Higher heating value 19.14 MJ/kg) for corn cob and (carbon 48.9 wt. %, hydrogen 6.01 wt. % and Higher heating value 18.06 MJ/kg) for corn stover. Corn cobs and corn stover contained very low amounts of nitrogen (0.41-0.57 wt. %) and sulphur (0.03-0.05 wt. %) compared with coal (nitrogen 0.8-1.9 wt. % and sulphur 0.7-1.2 wt. %), making them emit less sulphur oxides than when burning fossil fuels. The corn residues showed three distinct stages in the thermal decomposition process, with peak temperature of pyrolysis shifting to a higher value as the heating rate increased. The activation energies (E) for corn residues, obtained by the application of an iso-conversional method from thermogravimetric tests were in the range of 220 to 270 kJ/mol. The products obtained from fast pyrolysis of corn residues were bio-oil, biochar, water and gas. Higher bio-oil yields were produced from fast pyrolysis of corn residues in a bubbling fluidised bed reactor (47.8 to 51.2 wt. %, dry ash-free) than in a Lurgi twin screw reactor (35.5 to 37 wt. %, dry ash-free). Corn cobs produced higher bio-oil yields than corn stover in both types of reactors. At the optimised operating temperature of 500-530 °C, higher biochar yields were obtained from corn stover than corn cobs in both types of reactors. There were no major differences in the chemical and physical properties of bio-oil produced from the two types of reactors. The biochar properties showed some variation in heating values, carbon content and ash content for the different biomasses. The fast pyrolysis of corn residues produced energy products, bio-oil (Higher heating value = 18.7-25.3 MJ/kg) and biochar (Higher heating value = 19.8-29.3 MJ/kg) comparable with coal (Higher heating value = 16.2-25.9 MJ/kg). The bio-oils produced had some undesirable properties for its application such as acidic (pH 3.8 to 4.3) and high water content (21.3 to 30.5 wt. %). The bio-oil upgrading method (evaporation) increased the heating value and viscosity by removal of light hydrocarbons and water. The corn residues biochar produced had a BET Brynauer-Emmet-Teller (BET) surface area of 96.7 to 158.8 m2/g making it suitable for upgrading for the manufacture of adsorbents. The gas products from fast pyrolysis were analysed by gas chromatography (GC) as CO2, CO, H2, CH4, C2H4, C2H6, C3H8 and C5+ hydrocarbons. The gases had CO2 and CO of more than 80% (v/V) and low heating values (8.82-8.86 MJ/kg). AFRIKAANSE OPSOMMING: Die styging in olie pryse asook dreigende klimaatsveranderinge het daartoe gelei dat regerings, die samelewing asook die energie sektor alternatiewe energiebronne oorweeg. Biobrandstof as alternatiewe energiebron het in die afgope paar jaar redelik aftrek gekry. Termochemiese omskakelingsprosesse soos pirolise word oorweeg vir die omskakeling van goedkoop landbou afval na groen energie en waardevolle produkte. Snel piroliese van biomassa is een van die mees belowende tegnologië vir die omskakeling van biomassa na vloeibare brandstof en word tans gereken as ’n belowende kandidaat om petroleum brandstof te vervang. Mielieafval, stronke en strooi vorm ’n reuse deel van die Suid Afrikaanse landbou afval. Ongeveer 8900 duisend metrieke ton afval word jaarliks geproduseer wat optel na ongeveer 1.7% van die wêreld se mielie produksie uitmaak (Nation Master, 2005). Hierdie studie het gekk na die kinetika van piroliese, die karakterisering en kwaliteit van by-produkte van snel piroliese afkomstig van mielie-afval asook die opgradering van biobrandstof. Die eerste mikpunt was om die fisiese en chemiese karakteristieke van mielie-afval te bepaal om sodoende die geskiktheid van hierdie afval vir die gebruik tydens piroliese te bepaal. Tweendens is ’n kinetiese studie onderneem om reaksie parameters te bepaal asook die gedrag tydens termiese ontbinding waar te neem. Kennis van die piroliese kinetika van biomassa is van belang juis tydens die ontwerp en optimering van piroliese reaktore. Snel piroliese ekspermente is uitgevoer met behulp van twee verskillende reaktore: ’n Lurgi twee skroef reaktor en ’n borrelende gefluidiseerde-bed reaktor. Die produk opbrengs en kwaliteit is vergelyk. Eindelik is ’n voorlopige studie oor die opgradering van bio-olie uitgevoer deur te kyk na die verwydering van oortollige water en organiese materiaal om die kwaliteit van hierdie vloeibare brandstof te verbeter. Biomassa afkomstig van mielie-afval is ’n potensiële termochemiese voerbron met die volgende kenmerke: mielie stronke- (C - 50.21 massa %, H – 5.9 massa %, HHV – 19.14 MJ/kg); mielie strooi – (C – 48.9 massa %, H – 6.01 massa %, HHV – 18.06 MJ/kg). Beide van hierdie materiale bevat lae hoeveelhede N (0.41-0.57 massa %) and S (0.03-0.05 massa %) in vergelyking met steenkool N (0.8-1.9 massa %) and S (0.7-1.2 massa %). Dit beteken dat hieride bronne van biomassa laer konsentrasies van swael oksiedes vrystel in vergelyking met fossielbrandstowwe. Drie kenmerkende stadia is waargeneem tydens die termiese afbraak van mielie-afval, met die temperatuur piek van piroliese wat skuif na ’n hoër temperatuur soos die verhittingswaarde toeneem. Die waargenome aktiveringsenergie (E) van mielie-afval bereken met behulp van die iso-omskakelings metode van TGA toetse was in die bestek: 220 tot 270 kJ/mol. Die produkte verkry deur Snel Piroliese van mielie-afval was bio-olie, bio-kool en gas. ’n Hoër opbrengs van bio-olie is behaal tydens Snel Piroliese van mielie-afval in die borrelende gefluidiseerde-bed reakctor (47.8 na 51.2 massa %, droog as-vry) in vergelyking met die Lurgi twee skroef reakctor (35.5 na 37 massa %, droog as-vry). Mielie stronke sorg vir ’n hoër opbrengs van bio-olie as mielie strooi in beide reaktore. By die optimum bedryfskondisies is daar in beide reaktor ’n hoër bio-kool opbrengs verkry van mielie stingels teenoor mielie stronke. Geen aansienlike verskille is gevind in die chemise en fisiese kenmerke van van die bio-olie wat geproduseer is in die twee reaktore nie. Daar is wel variasie getoon in die bio-kool kenmerkte van die verskillende Snel Piroliese prosesse. Snel piroliese van mielie-afval lewer energie produkte, bio-olie (HVW = 18.7-25.3MJ/kg) en bio-kool (HVW = 19.8-29.3 MJ/kg) vergelykbaar met steenkool (HVW = 16.2-25.9 MJ/kg). Die bio-olies geproduseer het sommige ongewenste kenmerke getoon byvoorbeeld suurheid (pH 3.8-4.3) asook hoë water inhoud (21.3 – 30.5 massa %). Die metode (indamping) wat gebruik is vir die opgradering van bio-olie het gelei tot die verbetering van die verhittingswaarde asook die toename in viskositeit deur die verwydering van ligte koolwaterstowwe en water. Die mielie-afval bio-kool toon ’n BET (Brunauer-Emmet-Teller) oppervlakte area van 96.7-158.8 m2/g wat dit toepaslik maak as grondstof vir absorbante. The gas geproduseer tydens Snel Piroliese is geanaliseer met behulp van gas chromotografie (GC) as CO2, CO, H2, CH4, C2H4, C2H6, C3H8 and C5+ koolwaterstowwe. Die vlak van CO2 en CO het 80% (v/V) oorskry en met lae verhittingswaardes (8.82-8.86 MJ/kg).

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Johansson, Sara, and Michaela Eriksson. "Mattrender : Slow food vs Fast food." Thesis, Örebro universitet, Restaurang- och hotellhögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-33323.

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Uppsatsen är grundad på två aktuella mattrender. Den första är Slow Food som grundades av Carlo Petrini i strävan efter att alla råvaror skall framställas på ett sätt som inte skadar naturen, djurens välmående samt människans egen hälsa. Den andra är Fast Food, en bransch som istället handlar om den världsliga ekonomin där man vill producera olika produkter snabbare och billigare. Syftet med denna studie är att ge läsaren en inblick i Slow Food rörelsen kontra Fast Food branschen och ställa dem mot varandra ur ett miljöperspektiv. Uppsatsen är en litteraturbaserad studie där fyra artiklar utgör grunden för resultatet. Artiklarna visar de två trenderna på ett mer djupgående sätt genom positiva samt negativa aspekter utifrån ett miljöperspektiv. Massproduktionen av matvaror är något som idag tar över världen allt mer. Varor som odlas lokalt och på ett sätt som inte skadar djur och natur är något som Slow Food rörelsen försöker få in bland hemmen. Baksidan av Slow Food är att det inte finns ekonomiska resurser för att kunna föda världens befolkning på detta sätt. Fast Food är något som idag anses vara det bestående sättet att i framtiden odla och framställa mat, fast det på lång sikt kommer att förstöra vår miljö genom odlingstekniker och transporter. B-uppsatser

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Lönnqvist, Beatrice, and Cecilia Thörnblom. "Fast anställning kan ge låg arbetsmotivation." Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-15086.

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Tidigare forskning pekar på att medarbetare bland annat motiveras av balans mellan insats och belöning, förväntningar som är förenliga med organisationens visioner och instrumentell motivation. Åsikterna i forskningen skiljer sig åt i hur anställningsform påverkar graden av arbetstillfredsställelse. Syftet med studien var att, genom en kvantitativ metod, undersöka graden av arbetsmotivation hos lagermedarbetare. Detta utifrån Herzbergs hygien- och motivationsfaktorer. På platsen för studien hade sjukfrånvaron de senare åren ökat och organisationen var under en implementeringsfas av Lean production. Vidare diskuteras kring anställningsvillkors betydelse för motivation. Resultatet i studien visade att motivationen var högst bland de yngre medarbetarna som var tillfälligt anställda. Genom de öppna frågorna i enkäten framkom att arbetstiderna var en besvärande faktor på arbetsplatsen och att arbetskamrater ansågs som en positiv faktor. Organisationen AB bör öka dess autonomi över arbetstider och bör visa på utvecklingsmöjligheter för medarbetarna.

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Memmott, Matthew J. "Hydrogen production using a supercritical CO₂-cooled fast reactor and steam electrolysis." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/41307.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2007. Includes bibliographical references (p. 118-121). Rising natural gas prices and growing concern over CO₂ emissions have intensified interest in alternative methods for producing hydrogen. Nuclear energy can be used to produce hydrogen through thermochemical and/or electrochemical processes. This thesis investigates the feasibility of high temperature steam electrolysis (HTSE) coupled with an advanced gas-cooled fast reactor (GFR) utilizing supercritical carbon dioxide (S-CO₂) as the coolant. The reasons for selecting this particular reactor include fast reactor uranium resource utilization benefits, lower reactor outlet temperatures than helium-cooled reactors which ameliorate materials problems, and reduced power conversion system costs. High temperature steam electrolysis can be performed at conditions of 8500C and atmospheric pressure. However, compression of the hydrogen for pumping through pipes is unnecessary if electrolysis takes place at around 6 MPa. The reactor coolant at 6500C is used to heat the steam up to temperatures ranging between 2500C and 3500C, and the remaining heat is provided by thermal recuperation from product hydrogen and oxygen. Several different methods for integrating the hydrogen production HTSE plant with the GFR were investigated. The two most promising methods are discussed in more detail: extracting coolant from the power conversion system (PCS) turbine exhaust to boil water, and extracting coolant directly from the reactor using separate water boiler (WB) loops. Both methods have comparable thermal to electricity efficiencies (-43%) at 6500C. This relates to an overall hydrogen production efficiency of about 47%. The approach which utilizes separate WB loops has the added advantage of being able to provide emergency cooling to the reactor, and also the benefit of not interfering with the operation of the PCS. (cont.) This makes the separate WB loop integration method a more desirable scheme for hydrogen production using HTSE. The HTSE electrolysis unit adopted for the present analysis was designed by Ceramatec in coordination with INL. In this unit the steam flows into an electrolytic cell. It is separated by electron flow from a nickel-zirconium cathode to a strontium-doped lanthanum manganite anode. The optimal conditions for stack operation have been found by INL using various modeling and experimental techniques. These conditions include a 10% by volume flow of hydrogen in the feed, a stack operating temperature of 8000C, and an operating voltage of 1.2 V. The GFR integrated with the HTSE plant via separate water boiler loops was modeled in this work using the chemical engineering code ASPEN. The results of this model were benchmarked against the Idaho National Lab (INL) process, modeled using HYSIS. Both models predict a hydrogen production rate of -10.2 kg/sec (+ 0.2 kg/sec) for a 600 MWth reactor with an overall efficiency ranging between 47%-50%. The highly recuperated HTSE plant developed for the GFR can in principle be used in conjunction with a variety of other nuclear reactors, without requiring high reactor coolant outlet temperatures. by Matthew J. Memmott. S.M.

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Shemfe, Mobolaji B. "Performance assessment of biofuel production via biomass fast pyrolysis and refinery technologies." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/9880.

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Biofuels have been identified as one of several GHG emission strategies to reduce the use of fossil fuels in the transport sector. Fast pyrolysis of biomass is one approach to producing second generation biofuels. The bio-oil product of fast pyrolysis can be upgraded into essential gasoline and diesel range products with conventional refinery technologies. Thus, it is important to assess their techno- economic and environmental performance at an early stage prior to commercialisation. This research was conducted with the goal of evaluating and comparing the techno-economic and environmental viability of the production of biofuels from fast pyrolysis of biomass and upgrading of bio-oil via two refinery technologies, viz. hydroprocessing and zeolite cracking. In order to achieve this aim, process models of fast pyrolysis of biomass and bio-oil upgrading via hydroprocessing and zeolite cracking were developed. The fast pyrolysis model was based on multi-step kinetic models. In addition, lumped kinetic models of the hydrodeoxygenation reactions of bio-oil were implemented. The models were verified against experimental measurements with good prediction and formed the foundation for the development of a 72 t/day fast pyrolysis plant model in Aspen Plus®. Several strategies were proposed for the two pathways to enhance energy efficiency and profitability. All in all, the results revealed that the hydroprocessing route is 16% more efficient than the zeolite cracking pathway. Moreover, the hydroprocessing route resulted in a minimum fuel selling price of 15% lower than that from the zeolite cracking pathway. Sensitivity analysis revealed that the techno-economic and environmental performance of the both pathways depends on several process, economic and environmental parameters. In particular, biofuel yield, operating cost and income tax were identified as the most sensitive techno-economic parameters, while changes in nitrogen feed gas to the pyrolysis reactor and fuel yield had the most environmental impact. It was concluded that hydroprocessing is a more suitable upgrading pathway than zeolite cracking in terms of economic viability, energy efficiency, and GHG emissions per energy content of fuel produced.

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Fryklind, Louisa. "Kvalitetsarbete - från japanska sjön till fast mark." Thesis, Mälardalen University, Department of Innovation, Design and Product Development, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-429.

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SammanfattningSegerström Automotive tillverkar plåtkomponenter till kunder som Scania, Stiga och Volvo. Företaget befinner sig i en expansiv fas, men konkurrensen på marknaden är hård och kraven på god kvalitet höga. Företaget är kvalitets- och miljöcertifierat. Som del i förbättrings- och kvalitetsarbetet har en nystart av verksamhetens produktionssystem, SAPS (Segerström Automotive Production System), skett. Ett av företagets mål för de närmsta åren är att minska antalet externa reklamationer. Eftersom detta inte skett i önskad takt ansågs en utredning över vad som orsakat antalet reklamationer nödvändig. Examensarbetet har således inriktats mot att göra en nulägesanalys av kvalitetsarbetet inom verksamheten, med utgångspunkt i reklamationshanteringen, samt att påvisa eventuella förbättringsområden. Både kvalitativa och kvantitativa metoder har använts; så som intervjuer, insamling av sekundär och primärdata samt observationer. Teoridelens tyngdpunkt ligger i teorier inom lean production och Total Quality Management.En avvikelse uppstår när en produkt ej uppfyller kundens behov. En reklamation är ett sätt att kommunicera en avvikelse. De externa reklamationerna mot Segerström visade sig ofta vara symtom på interna avvikelser. Då det idag saknas ett system för interna reklamationer fångas dessa inte alltid upp. Ofta saknas tid och resurser för att genomföra en djupare orsaksanalys och vidta åtgärder. Felkällan elimineras inte alltid och samma fel återkommer. Delar av den upplevda resursbristen skulle kunna lösas genom en organisatorisk förändring, där tydliga roller för förbättrings- och kvalitetsarbete inom produktionen tas fram.Företaget har redan en mängd olika dokument och metoder för kvalitets- och förbättringsarbete, men dessa tycks inte ha förankrats i verksamheten i tillräcklig utsträckning. Utmaningen för företaget är att välja vilka dokument och metoder som skall användas samt att sedan förverkliga dessa. Rutiner bör skapas för att knyta ihop de olika delarna, metoderna och dokumenten. Att standardisera och dokumentera fler av de repetitiva aktiviteterna, identifiera interna kunder, analysera vart i kedjan detaljer bör mätas, etablera kommunikationsforum, utse kvalitetsansvariga i produktionen, utbilda personal inom kvalitetsområdet, ta fram belöningssystem, knyta kostnader direkt till kvalitetsrelaterade ärenden samt att analysera hur information om kvalitet kan samlas in och spridas till berörd personal är områden som företaget rekommenderas att titta närmare på.Viktigt är att ledningen ger nödvändiga resurser, skapar en struktur att utgå ifrån samt följer upp kvalitetsarbetet. För att lyckas måste kvalitet bli en prioriterad fråga i hela verksamheten. AbstractSegerström Automotive manufacture sheet metal components to customers like Scania, Stiga and Volvo. The company is expanding, but the competitiveness and the quality requirements on the market are high. The company is quality certified. As part of the work with quality and improvements Segerström Automotive Production System, SAPS, was restarted during the spring 2007. One of the goals for the organization is to decrease the number of external reclamations. To be able to reach the goal a study of what have caused the stagnation of the number of reclamations towards the company was considered as necessary. Thus the thesis has been focused on analyzing the quality work within the organization, with its core in the reclamation handling. Areas for improvements have also been discussed. Both qualitative and quantitative methods have been used; for example interviews, data gathering and observations. The main theories used come from lean production and Total Quality Management.A deviation occurs when a product does not meet the customer requirements. Reclamations communicate a deviation. It was found that the external reclamations towards Segerström often were symptoms of internal deviations. Because there is no system for internal reclamations the deviations that are found internally rarely lead to any actions. There is often a lack of time and resources dedicated to analyze the root cause and to take necessary actions to eliminate them; the failure modes are repeated. Parts of the lack of resources could be solved by an organizational change, where clear roles and responsibilities within the fields of quality and improvements were specified.The company already has a number of different documents and methods to work with quality and improvements, but those are not implemented and used in a necessary extent. The challenge for Segerström is to choose which documents and methods to use and how to implement them. Routines should be created to link the different parts, methods and documents. To standardize and document more of the repetitive activities, identify internal customers, analyze where in the chain details should be measured, establish channels for communication, have quality responsible persons at the work stations in the production, educate the personnel in quality, create a system for recognition and rewards, document costs of quality and analyze how to gather and spread information about quality to the personnel are areas as the company should look closer into.It is important that the leaders of the company give the resources necessary, builds a structure to work from and follow up the work. To succeed quality has to be prioritized within the whole organization.

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Islam, Shahina. "Improvement of Erythrina variegata L. : a multipurpose fast-growing tree species in Bangladesh." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336678.

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Stubbe, Kilian. "Development and Simulation Assessment of Semiconductor Production System Enhancements for Fast Cycle Times." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-27343.

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Long cycle times in semiconductor manufacturing represent an increasing challenge for the industry and lead to a growing need of break-through approaches to reduce it. Small lot sizes and the conversion of batch processes to mini-batch or single-wafer processes are widely regarded as a promising means for a step-wise cycle time reduction. Our analysis with discrete-event simulation and queueing theory shows that small lot size and the replacement of batch tools with mini-batch or single wafer tools are beneficial but lot size reduction lacks persuasive effectiveness if reduced by more than half. Because the results are not completely convincing, we develop a new semiconductor tool type that further reduces cycle time by lot streaming leveraging the lot size reduction efforts. We show that this combined approach can lead to a cycle time reduction of more than 80%.

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Lavoie, Jean-Philippe. "Production of pure ion beams by laser ionization and a fast release RFQ." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27202/27202.pdf.

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Bondesson, Per, and Stefan Liss. "Lean Production & Sustainable Supply Chains in the Fast Moving Consumer Goods Industry." Thesis, KTH, Industriell produktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-200528.

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The Fast Moving Consumer Goods (FMCG) industry consists of a large part of our daily purchases making it to an important industry for the society. Within every industry, operational control and supply chains are important success factors regarding efficiency and profitability. Lately, much attention towards sustainability within the industry has been given, due to environmental and to ethical concerns. The whole industry will be forced to undergo major changes in order to remain and to become sustainable. Therefore, operational control and supply chains need to be effective and sustainable in order to sustain this transformation. In this project, an investigation regarding if Lean production and sustainable supply chains can apply to the FMCG industry is conducted. Difficulties with achieving levelled production and factors to attend to in order to become sustainable will be addressed. A literature review about Lean management and sustainable supply chains will be presented. Furthermore, two case studies will be conducted at two beverage companies where a comparison between theory and reality will be conducted. We found that many of the Toyota Production System (TPS) principles can be hard to implement in the FMCG industry. Therefore, Lean production is not easily obtained within the FMCG industry. Specifically, we found that beverage companies have difficulties obtaining levelled production and implementing production levelling tools suggested in TPS. We found that measures conducted in order to level production mainly focus on optimization of internal processes and shortening of lead times upstream. Work to obtain control over demand management has been done on order to facilitate levelling of the production. Therefore, work to be conducted in order accomplish demand managementis suggested as a recommendation in this report. This recommendation contains factors such as: order placement, lead times pricing and campaigns. Several factors suggested in Sustainable Supply Chain Management literature in order to obtain sustainable supplychains were found in our case studies. We found that information exchange between customer and producer is not optimal. Furthermore, we found that high standards regarding suppliers generally result in that only large suppliers can meet these standards. Thus, making it harder to influence aspects regarding sustainability among suppliers. In closing, the FMCG industry have potential to achieve sustainable supply chains, but some factors remain to be improved. Fast Moving Consumer Goods (FMCG) industrin utgör de produkter som konsumeras på daglig basis, vilket gör den till en viktig industri för konsumtionssamhället i stort. Inom alla industrier utgör styrning av interna processer och försörjningskedjor viktiga framgångsfaktorer gällandes effektivitet och lönsamhet. Senaste tiden har det riktats mycket uppmärksamhet mot hållbarhets- och etiska aspekter inom hela industrin. Många intressenter menar på att alla industrier måste ändras för att industrin som helhet ska överleva och bli hållbar. Därför måste interna processer och försörjningskedjor anpassas för att stödja transformationen mot hållbarhet. I detta projekt undersöks ifall Lean produktion och hållbara försörjningskedjor kan anpassas till FMCG industrin. Vi kommer särskilt diskutera de svårigheter som finns med att uppnå utjämnat produktionsflöde och faktorer som är viktiga att åtgärda för att erhålla hållbarhet inom förädlingskedjan. En litteraturstudie kring Lean och hållbara försörjningskedjor kommer att utföras. Vidare kommer två fallstudier på två dryckesföretag att genomföras där en jämförelse mellan teori och verklighet kommer ligga tillgrund för våra slutsatser. De upptäckter vi gjorde under arbetet var att många av de fundamentala Lean-principer(TPS) som Toyota introducerar är svåra att uppnå inom FMCG-industrin. Mer specifikt fann vi i våra fallstudier att uppnå ett jämnt produktionsflöde tillhör en av de största svårigheterna inom dryckesindustrin. Vi upptäckte att det arbete som utförts för att uppnå ett jämnt produktionsflöde mestadels fokuserade på att förbättra interna processer och ledtider uppströms i försörjningskedajan. Arbete kring att kontrollera efterfrågan i syfte att utjämna produktionen har gjorts. I rapporten föreslås områden att undersöka för att bättre styra efterfrågan i form av en rekommendation. Denna rekomendation innehåller faktorer som: orderingång, prisättning av leverans och kampanjer. Flertalet av de hållbarhetsfaktorer som läggs fram i litteraturen kring hur man erhåller hållbara försörjningskedjor återfanns i våra fallstudier. Vi fann att faktorer som informationsutbyte mellan kund och producent inte är optimalt. Vidare utgör höga krav på leverantörer att generellt sett stora leverantörer blir de enda som möter uppsatta krav. Detta försvårar möjligheter att påverka leverantören. I detta fall, påverkan kring hållbarhetsaspekter. FMCG industrin har stora möjligheter att erhålla hållbara försörjningskedjor, men några faktorer återstår att förbättra. Dessa faktorer kommer diskuteras i rapporten.

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11

Kalgo, Abba Sani. "The development and optimisation of a fast pyrolysis process for bio-oil production." Thesis, Aston University, 2011. http://publications.aston.ac.uk/15808/.

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A two-tier study is presented in this thesis. The first involves the commissioning of an extant but at the time, unproven bubbling fluidised bed fast pyrolysis unit. The unit was designed for an intended nominal throughput of 300 g/h of biomass. The unit came complete with solids separation, pyrolysis vapour quenching and oil collection systems. Modifications were carried out on various sections of the system including the reactor heating, quenching and liquid collection systems. The modifications allowed for fast pyrolysis experiments to be carried out at the appropriate temperatures. Bio-oil was generated using conventional biomass feedstocks including Willow, beechwood, Pine and Miscanthus. Results from this phase of the research showed however, that although the rig was capable of processing biomass to bio-oil, it was characterised by low mass balance closures and recurrent operational problems. The problems included blockages, poor reactor hydrodynamics and reduced organic liquid yields. The less than optimal performance of individual sections, particularly the feed and reactor systems of the rig, culminated in a poor overall performance of the system. The second phase of this research involved the redesign of two key components of the unit. An alternative feeding system was commissioned for the unit. The feed system included an off the shelf gravimetric system for accurate metering and efficient delivery of biomass. Similarly, a new bubbling fluidised bed reactor with an intended nominal throughput of 500g/h of biomass was designed and constructed. The design leveraged on experience from the initial commissioning phase with proven kinetic and hydrodynamic studies. These units were commissioned as part of the optimisation phase of the study. Also as part of this study, two varieties each, of previously unreported feedstocks namely Jatropha curcas and Moringa olifiera oil seed press cakes were characterised to determine their suitability as feedstocks for liquid fuel production via fast pyrolysis. Consequently, the feedstocks were used for the production of pyrolysis liquids. The quality of the pyrolysis liquids from the feedstocks were then investigated via a number of analytical techniques. The oils from the press cakes showed high levels of stability and reduced pH values. The improvements to the design of the fast pyrolysis unit led to higher mass balance closures and increased organic liquid yields. The maximum liquid yield obtained from the press cakes was from African Jatropha press cake at 66 wt% on a dry basis.

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12

Asquith, Nicola Louise. "Fast and thermal Accelerator Driven Systems: Studies of secondary particle production and transport." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14150.

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Accelerator Driven Systems (ADS) consist of a spallation neutron source coupled to a sub-critical nuclear assembly and are a proposed technology for the transmutation of nuclear waste and electricity generation. The Gamma-3 assembly of the Joint Institute for Nuclear Research (JINR), Dubna, Russia consists of a lead spallation target surrounded by graphite. The target was irradiated with 1.6 GeV deuterons and the neutron capture and fission rate of 232Th within the assembly were experimentally measured. These two reactions are fundamental to the performance and feasibility of 232Th in an ADS. The spatial distribution of slow neutrons on the surface of the graphite was also measured using CR-39 track detectors coupled to LR-115 2B film. The Quinta assembly, also located at the JINR, is composed of 512 kg of natural uranium surrounded by a lead reflector. It was irradiated with 1 and 4 GeV deuterons and the fission rate of natU, 232Th, 209Bi, natPb and 197Au was measured using mica track detectors. These materials are proposed fuel and/or target materials in future ADS. (n,γ) and (n,xn) reaction rates of 209Bi and 197Au were also determined through gamma spectrometry. Experimental reaction rates were compared to those calculated using the MCNPX 2.7 code with the INCL4/ABLA and CEM03 physics models. Evaluated cross-section libraries were used whenever available, otherwise reaction cross section data were retrieved from the literature or calculated using the TALYS and XSEX3 codes. Good agreement between the experimental and calculated results were found, although in general, the INCL4-ABLA model produced a closer agreement with the experimental results compared to CEM03. This study serves as a good validation for the computational models and cross section data used to simulate secondary particle production and transport in thermal and fast ADS. Future development of ADS will inevitably rely upon accurate and well validated simulation codes and nuclear data.

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13

Healy, Guy Hamilton. "Fast and furious film-making: Emerging hybrid online-TV production practices in Australia." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/203318/3/Guy_Healy_Thesis.pdf.

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This study reveals distinctive new forms of screen industry convergence with deep implications for creators themselves and the screen industry in general. It is the first longitudinal study of veteran YouTubers and established TV producers making highly popular serial narrative web-series together, and it shows the professional outcomes from this rapprochement. Fourteen teams from the Google/Screen Australia initiative Skip Ahead and three teams of professional writer-producers were tracked as they launched web-series on YouTube. This study showed the majority of teams parlayed highly viewed web-series into license deals with digital broadcasters and online streamers, and thus potentially sustainable careers.

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14

Jimenez, Eduardo Antonio. "Fast history matching of time-lapse seismic and production data for high resolution models." Diss., Texas A&M University, 2008. http://hdl.handle.net/1969.1/85950.

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Integrated reservoir modeling has become an important part of day-to-day decision analysis in oil and gas management practices. A very attractive and promising technology is the use of time-lapse or 4D seismic as an essential component in subsurface modeling. Today, 4D seismic is enabling oil companies to optimize production and increase recovery through monitoring fluid movements throughout the reservoir. 4D seismic advances are also being driven by an increased need by the petroleum engineering community to become more quantitative and accurate in our ability to monitor reservoir processes. Qualitative interpretations of time-lapse anomalies are being replaced by quantitative inversions of 4D seismic data to produce accurate maps of fluid saturations, pore pressure, temperature, among others. Within all steps involved in this subsurface modeling process, the most demanding one is integrating the geologic model with dynamic field data, including 4Dseismic when available. The validation of the geologic model with observed dynamic data is accomplished through a "history matching" (HM) process typically carried out with well-based measurements. Due to low resolution of production data, the validation process is severely limited in its reservoir areal coverage, compromising the quality of the model and any subsequent predictive exercise. This research will aim to provide a novel history matching approach that can use information from high-resolution seismic data to supplement the areally sparse production data. The proposed approach will utilize streamline-derived sensitivities as means of relating the forward model performance with the prior geologic model. The essential ideas underlying this approach are similar to those used for high-frequency approximations in seismic wave propagation. In both cases, this leads to solutions that are defined along "streamlines" (fluid flow), or "rays" (seismic wave propagation). Synthetic and field data examples will be used extensively to demonstrate the value and contribution of this work. Our results show that the problem of non-uniqueness in this complex history matching problem is greatly reduced when constraints in the form of saturation maps from spatially closely sampled seismic data are included. Further on, our methodology can be used to quickly identify discrepancies between static and dynamic modeling. Reducing this gap will ensure robust and reliable models leading to accurate predictions and ultimately an optimum hydrocarbon extraction.

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15

Joglekar, Nitindra R. "The technology treadmill : managing product performance and production ramp-up in fast-paced industries." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/9817.

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16

Alves, Carmen Lucia Rodrigues. "O evangelho segundo o McDonald's: estudo sobre o processo de produção da fast-food." Pontifícia Universidade Católica de São Paulo, 2006. https://tede2.pucsp.br/handle/handle/12967.

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Made available in DSpace on 2016-04-27T19:31:27Z (GMT). No. of bitstreams: 1 HIS - Carmen Lucia Rodrigues Alves.pdf: 1078309 bytes, checksum: 1d380777dc66c76acec9d69121b423ee (MD5) Previous issue date: 2006-10-05 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior This study approaches the production process of McDonald´s fast food chain, recovering the way their meals are produced, the technology invested on them, the definitions about color, scent, taste, as well as the labor relations, from worker´s functional structure, to employees´ selection and training in order to allow them to accomplish all functions that substantiate the production process. By analysing McDonald´s products advertising, this study also focus on the ideology it diffuses, particularly due to the fact that McDonald´s is a fast food chain of global extent Este estudo aborda o processo de produção da cadeia de fast-food McDonald s, resgatando a forma de produzir seus alimentos, a tecnologia investida, as definições sobre cor, aroma, gosto; as relações de trabalho, desde a estrutura funcional dos trabalhadores, a seleção dos funcionários e o treinamento para cumprir todas as funções que concretizam o processo produtivo. Enfoca, também, através da análise da propaganda de seus produtos, a ideologia que veicula, particularmente por ser uma cadeia de âmbito global

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17

Harms, Allan. "Fast pyrolysis and nitrogenolysis of biomass and biogenic residues : production of a sustainable slow release fertiliser." Thesis, Aston University, 2013. http://publications.aston.ac.uk/18728/.

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The production of agricultural and horticultural products requires the use of nitrogenous fertiliser that can cause pollution of surface and ground water and has a large carbon footprint as it is mainly produced from fossil fuels. The overall objective of this research project was to investigate fast pyrolysis and in-situ nitrogenolysis of biomass and biogenic residues as an alternative route to produce a sustainable solid slow release fertiliser mitigating the above stated problems. A variety of biomasses and biogenic residues were characterized by proximate analysis, ultimate analysis, thermogravimetric analysis (TGA) and Pyrolysis – Gas chromatography – Mass Spectroscopy (Py–GC–MS) for their potential use as feedstocks using beech wood as a reference material. Beech wood was virtually nitrogen free and therefore suitable as a reference material as added nitrogen can be identified as such while Dried Distillers Grains with Solubles (DDGS) and rape meal had a nitrogen content between 5.5wt.% and 6.1wt.% qualifying them as high nitrogen feedstocks. Fast pyrolysis and in-situ nitrogenolysis experiments were carried out in a continuously fed 1kg/h bubbling fluidized bed reactor at around 500°C quenching the pyrolysis vapours with isoparaffin. In-situ nitrogenolysis experiments were performed by adding ammonia gas to the fast pyrolysis reactor at nominal nitrogen addition rates between 5wt.%C and 20wt.%C based on the dry feedstock’s carbon content basis. Mass balances were established for the processing experiments. The fast pyrolysis and in-situ nitrogenolysis products were characterized by proximate analysis, ultimate analysis and GC– MS. High liquid yields and good mass balance closures of over 92% were obtained. The most suitable nitrogen addition rate for the in-situ nitrogenolysis experiments was determined to be 12wt.%C on dry feedstock carbon content basis. However, only a few nitrogen compounds that were formed during in-situ nitrogenolysis could be identified by GC–MS. A batch reactor process was developed to thermally solidify the fast pyrolysis and in-situ nitrogenolysis liquids of beech wood and Barley DDGS producing a brittle solid product. This was obtained at 150°C with an addition of 2.5wt% char (as catalyst) after a processing time of 1h. The batch reactor was also used for modifying and solidifying fast pyrolysis liquids derived from beech wood by adding urea or ammonium phosphate as post processing nitrogenolysis. The results showed that this type of combined approach was not suitable to produce a slow release fertiliser, because the solid product contained up to 65wt.% of highly water soluble nitrogen compounds that would be released instantly by rain. To complement the processing experiments a comparative study via Py–GC–MS with inert and reactive gas was performed with cellulose, hemicellulose, lignin and beech wood. This revealed that the presence of ammonia gas during analytical pyrolysis did not appear to have any direct impact on the decomposition products of the tested materials. The chromatograms obtained showed almost no differences between inert and ammonia gas experiments indicating that the reaction between ammonia and pyrolysis vapours does not occur instantly. A comparative study via Fourier Transformed Infrared Spectroscopy of solidified fast pyrolysis and in-situ nitrogenolysis products showed that there were some alterations in the spectra obtained. A shift in frequencies indicating C=O stretches typically related to the presence of carboxylic acids to C=O stretches related to amides was observed and no double or triple bonded nitrogen was detected. This indicates that organic acids reacted with ammonia and that no potentially harmful or non-biodegradable triple bonded nitrogen compounds were formed. The impact of solid slow release fertiliser (SRF) derived from pyrolysis and in-situ nitrogenolysis products from beech wood and Barley DDGS on microbial life in soils and plant growth was tested in cooperation with Rothamsted Research. The microbial incubation tests indicated that microbes can thrive on the SRFs produced, although some microbial species seem to have a reduced activity at very high concentrations of beech wood and Barley DDGS derived SRF. The plant tests (pot trials) showed that the application of SRF derived from beech wood and barley DDGS had no negative impact on germination or plant growth of rye grass. The fertilizing effect was proven by the dry matter yields in three harvests after 47 days, 89 days and 131 days. The findings of this research indicate that in general a slow release fertiliser can be produced from biomass and biogenic residues by in-situ nitrogenolysis. Nevertheless the findings also show that additional research is necessary to identify which compounds are formed during this process.

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18

BERTO, FEDERICO. "A new setup and methods for the fast production of ultracold atoms for atom-ion experiments." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2962242.

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19

Okada, Hiroyuki. "Study of Fast Ion Production and Confinement in Ion Cyclotron Range of Frequency Heating of Heliotron E." Kyoto University, 1999. http://hdl.handle.net/2433/156985.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである Kyoto University (京都大学) 0048 新制・論文博士 博士(エネルギー科学) 乙第10279号 論エネ博第9号 新制||エネ||4(附属図書館) UT51-99-Z54 (主査)教授佐野史道, 教授若谷誠宏, 教授近藤克己 学位規則第4条第2項該当

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20

Suggett, David John. "Variability of phytoplankton production rates in the Atlantic Ocean as observed using the Fast Repetition Rate Fluorometer." Thesis, University of Southampton, 2000. https://eprints.soton.ac.uk/42172/.

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This thesis examines some aspects of in situ phytoplankton physiology and subsequent production rates within the Atlantic Ocean, as observed using a novel instrument, the Fast Repetition Rate Fluorometer (FRRF). The underlying theory and use of this instrument is described in detail. High resolution FRRF data collection was performed during three oceanographic cruises: RV Pelagia, March 1998, RRS James Clark Ross, May-June 1998 and RRS Challenger, August 1999. These data observe characteristics of phytoplankton physiology and, therefore, production, over daily (diel), small (turbulent) and broad (seasonal) scales. The sampling sites for all cruises were chosen within a variety of hydrographic regimes to further assess the light-nutrient dependencies of this variability. Phytoplankton physiology is described by the functional absorption cross section (CJPSII) and the quantum yield of photochemistry (F^./FjJ which relate to the rate at which photosystem II (PSII) saturates with light and the proportion of functional PSII reaction centres, respectively. Changes in both GPSII and Fv/Fm are most evident at the diel scale. 0pSn correlates with corresponding changes in PSII pigments indicating non-photochemical quenching of excess solar energy as part of a diel rhythm in cellular constituents. A novel calculation for the number of in situ PSII reaction centres (npsn), based on FRRF measurements, is described and tested and shows similar diel variability. Smaller-scale variations in GPSII are also observed continually throughout the diel period apparently as an attempt to balance the distribution of energy between PSII and PSI and, therefore, maintain high rates of photosynthesis. Such smaller-scale processes are most obvious in low nutrient (oligotrophic) waters where hydrographic variability and consequently new nutrient input, remains relatively low. FRRF estimates of production were most related to nutrient conditions in these oligotrophic waters. Conversely, production correlated with light in waters where nutrients were in abundance. FRRF production estimates compared well with corresponding in situ gross O2 measurements but were typically a factor of 3-4 higher than 14C production estimates. This difference can be accounted as the stochiometry between O2 evolution and carbon uptake for photosynthesis but may also represent the limitations associated with the calculation of production from one or both techniques. These limitations are discussed as a premise for further work.

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21

Gheitasi, Parvin. ""Say It Fast, Fluent and Flawless" : formulaicity in the oral language production of young foreign language learners." Doctoral thesis, Umeå universitet, Institutionen för språkstudier, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-132249.

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This thesis reports on a study, which investigated the process of early foreign language learning in a classroom context and the functions of multi-word units of language known as formulaic sequences in the oral language production of young foreign language learners. A classroom with 11 students in the age range 9 to 11 years was observed and video recorded for 16 sessions (90 minutes per session). The observations were accompanied by two elicitation tasks. 10 sessions out of the 16 sessions of the collected speech samples were transcribed chronologically. In the next step, formulaic sequences were identified based on pre-established criteria, which were further developed during the analysis. The data was analyzed in order to identify the functions of formulaic sequences in learners’ oral language production in addition to the inter-learner variations in the application of formulaic sequences for different functions. The results revealed evidence of incidental learning of formulaic sequences from input; the language input provided instances for the learners to learn multi-word units. In addition, formulaic sequences played different roles in the language production of the learners. These sequences helped young language learners to overcome their lack of knowledge, to improve their fluency, and to enjoy some language play. Formulaic sequences were used as a strategy to economize effort on processing and also to buy time for processing. The findings of the study suggested that language users might introduce dis-fluency in the production of their sequences in order to buy time for further processing. Moreover, the data provided examples illustrating communicative functions of formulaic sequences where the use of formulaic sequences was affected by the relationship between the speaker and listener. The analysis revealed that although all the learners applied formulaic sequences in their language production, there was a great variation among individual learners in their intention and the extent of the application of formulaic sequences. Some learners used these sequences to be able to extend their utterances and produce more of the language, whereas other learners used them to avoid further language production. In sum, it seemed that individual learners' different personalities, needs or limitations served as explanation for the application of formulaic sequences in different contexts.

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22

Lima, Ana Rebeca Castro [UNESP]. "Investigação sobre o efeito da temperatura na produção de calor em cabras da raça Saanen e Anglo-Nubiana." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151782.

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Esta opção é utilizada caso você tenha planos de publicar seu trabalho em periódicos científicos ou em formato de livro, por exemplo e fará com que apenas as páginas pré-textuais, introdução, considerações e referências sejam disponibilizadas. Se optar por disponibilizar o texto completo de seu trabalho imediatamente selecione no campo “Data para a disponibilização do texto completo” a opção “Não se aplica (texto completo)”. Isso fará com que seu trabalho seja disponibilizado na íntegra no Repositório Institucional UNESP. Por favor, corrija esta informação realizando uma nova submissão. Agradecemos a compreensão. on 2017-09-28T12:44:18Z (GMT) Submitted by ANA REBECA CASTRO LIMA null (anarebecalima@hotmail.com) on 2017-09-30T14:34:04Z No. of bitstreams: 1 Tese_rebeca_com_certificado.pdf: 1529070 bytes, checksum: c56d5fa5c704e63a65dc06b2c95fb45d (MD5) Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-10-02T16:59:38Z (GMT) No. of bitstreams: 1 lima_arc_dr_jabo.pdf: 1529070 bytes, checksum: c56d5fa5c704e63a65dc06b2c95fb45d (MD5) Made available in DSpace on 2017-10-02T16:59:38Z (GMT). No. of bitstreams: 1 lima_arc_dr_jabo.pdf: 1529070 bytes, checksum: c56d5fa5c704e63a65dc06b2c95fb45d (MD5) Previous issue date: 2017-08-07 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Objetivou-se com o presente estudo determinar a influência da temperatura ambiente sobre o metabolismo basal e a partição de energia em cabras Saanen e Anglo-Nubiana. Dois experimentos foram conduzidos utilizando-se seis cabras da raça Saanen e seis cabras da raça Anglo-Nubiana, em mantença, a partir da técnica da calorimetria indireta de circuito aberto, com máscaras faciais. No experimento 1, após um período de alimentação de 3 dias, os animais foram submetidos a jejum e a medição das trocas gasosas foi realizada durante 30 min a 0, 12, 20, 36, 44, 60 e 68 horas após jejum. A produção de metano foi igual a zero após 31 horas de jejum para cabras Saanen e 40 horas para as Anglo-Nubiana. Os resultados sugerem que o período ideal para medir a produção de calor em jejum (PCJ) deve ser entre 40 horas e 60 horas de jejum para cabras em mantença. No experimento 2, as cabras foram submetidas a três diferentes temperaturas: 10 ºC ± 0,23; 20 ºC ±0,41 e 35 ºC ±1,05. Após um período de alimentação de 4 dias, os animais foram submetidos a jejum por 60 horas e a medição da troca gasosa foi realizada a partir da metodologia da calorimetria indireta utilizando as máscaras faciais durante 30 min em cada animal aleatoriamente. Para ambas as raças, houve uma diminuição linear na ingestão de matéria seca (MS) e matéria orgânica (MO; P<0,10) a medida que a temperatura aumentou de 10 para 35ºC. A digestibilidade aparente da MS, da MO, da proteína bruta e da fibra em detergente neutro apresentaram comportamento quadrático (P < 0,10), com menores valores na temperatura de 20ºC. Aos 35ºC, a digestibilidade da proteína bruta das cabras Anglo-Nubiana foi maior que a das cabras Saanen. A frequência respiratória (FR) e volume respiratório aumentaram em taxas crescentes com o aumento da temperatura ambiente. Aos 35ºC, tanto a FR quanto o volume respiratório das cabras Saanen foram maiores que o das cabras Anglo-Nubiana. A metabolizabilidade e a energia metabolizável da dieta das cabras Saanen, aos 35ºC, foram menores que as das cabras Anglo-Nubiana. Em ambas as raças, para cada 1ºC de variação abaixo de 20ºC houve um aumento na produção de calor (PC) na ordem de 6,7 kJ/ kg0,75 PV, enquanto que para cada 1ºC de variação acima de 20ºC houve um aumento na PC na ordem de 7,9 kJ/ kg0,75 PV. Por outro lado, para PCJ indicou que para cada 1ºC de variação abaixo de 20ºC houve um decréscimo na PCJ na ordem de 5,4 kJ/ kg0,75 PV, enquanto que para cada 1ºC de variação acima de 20ºC houve um decréscimo na ordem de 8,7 kJ/ kg075 PV, em temperatura ambiente entre 10 e 35ºC. As cabras da raça Saanen e Anglo-Nubiana são capazes de manter a homeostasia em ambientes entre 10 e 35ºC. Por outro lado, o aumento da temperatura ambiental induz a um menor consumo, tendendo a balanços energéticos negativos. Acima de 20ºC, as cabras tendem a diminuir a produção de calor em jejum, como uma tentativa de conservação de energia em ambientes quentes. The aim of this study was to determine the influence of the ambient temperature on the basal metabolism and the energy partition in Saanen and Anglo-Nubian goats. Two experiments were carried out using six Saanen goats and six Anglo-Nubian goats, in maintenance, using the indirect calorimetry technique with open-circuit facemask respirometry. In experiment 1, after a three-day feed period, the animals were fasted and gas exchange measurements were performed for 30 min at 0, 12, 20, 36, 44, 60 and 68 hours after fasting. Methane production approached zero after 31 hours of fasting for Saanen goats and 40 hours for Anglo-Nubian goats. The results suggest that the period for measuring fasting heat production (FHP) should be between 40 hours and 60 hours of fasting for maintenance goats. In experiment 2, goats were submitted to three different temperatures: 10 ºC ± 0.23, 20 ºC ± 0.41 and at 35 ºC ± 1.05. After a feeding period of four days, goats were fasted for 60 hours and gas exchange measurement was performed for 30 min in each animal randomly. For both breeds, dry matter (DM) and organic matter intake (MO; P <0.10) decrease linearly as the temperature increased from 10 to 35ºC. The apparent digestibility of DM, OM, crude protein and neutral detergent fiber presented quadratic behavior (P <0.10), with the lowest values at 20ºC. At 35ºC, the crude protein digestibility of Anglo-Nubian goats was higher than that of Saanen goats. Respiratory rate (RR) and respiratory volume increased with increasing ambient temperature. At 35ºC, both RR and respiratory volume of Saanen goats were higher than that of Anglo-Nubian goats. The diet metabolizability and metabolizable energy of Saanen goats, at 35ºC, were lower than those of the Anglo-Nubian goats. In both breeds, for each 1ºC of variation below 20ºC there was an increase in HP of 6.7 kJ/kg0.75 BW, whereas for each 1ºC of variation above 20ºC there was an increase in HP of 7.9 kJ/kg0.75 BW. On the other hand, FHP indicated that for each 1ºC of variation below 20ºC there was a decrease in FHP of 5.4 kJ/kg0.75 BW, while for each 1ºC of variation above 20ºC there was a decrease of 8.7 kJ/kg0.75 BW, between 10 and 35 °C. Saanen and Anglo-Nubian goats are able to maintain homeostasis in environments between 10 and 35ºC. On the other hand, the increase in ambient temperature leads to lower consumption, tending to negative energy balances. Above 20°C, goats tend to decrease fasting heat production, as an attempt to conserve energy in hot environments. CNPq: 157525/2014-7

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23

Pamuk, Haki. "The Impact Of Modern Retailing On The Prices Of Fast Moving Consumer Goods: Evidence From Turkey." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610043/index.pdf.

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In Turkey, the retailing sector is in a modernization process with the increase in the market share of supermarkets since 1990s. This process has important implications on general economy with changing consumption characteristics. This thesis analyzes the impact of increasing market share of supermarkets on the prices of fast moving consumer goods in traditional retailers. By means of a household panel, a panel data econometric approach is used for assessing the impacts of different supermarket formats between 2002 and 2006 in 12 sectors. The results indicates that increasing market share supermarkets decreases the price levels observed in traditional retailers in some of the sectors and these impacts vary according to supermarket formats and sectors.

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24

Austin, Peter Dalton. "An Evaluation Of Vermicompost As A Fast-Acting Nitrogen Amendment To Mitigate Nitrogen Deficiencies In Organic Vegetable Production." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/505.

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For sustained production, organic agriculture depends on plant needs being synchronized with the release of nutrients from organic amendments during decomposition within the soil. Because decomposition is strongly dependent on soil moisture and temperature, nutrient needs may not always be met as planned or synchronous with plant need. Unlike conventional agriculture, fast acting amendments are not readily available. Much of the evidence that vermicompost benefits crop production comes from studies on seed germination and production of starts in greenhouses. Yet, there is a dearth of information derived from field studies. Soil, soil and water nitrogen, plant development, and marketable yield were investigated by implementing field plot trials with both starts grown in greenhouses (Experiment 1) and directly seeded (Experiment 2) crops to test hypotheses on fertility, economics and environmental impacts. Results from Experiment 1 showed that plant production was dramatically increased both in the greenhouse as well as subsequently in the field for vermicompost treatments and directly correlates to economic differences. Results from Experiment 2 show that plant production differences between compost treatments vary by site. There was no significant difference in soil and soil water NO3-N, NH4-N and Total Inorganic Nitrogen (TIN) among treatments, site or experiment. The timely rate of plant development in greenhouse started VC treatments shows great potential to be the first to market with fresh produce when other treatments are still waiting to transplant.

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25

Ranasinghe, D. M. S. Hemanthi K. "The effect of management influences on biomass production, biomass distribution and the nutrient distribution of fast growing woody species." Thesis, Bangor University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327760.

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26

Razzaque, Md Abdur. "Development and assessment of a fast pyrolysis reactor for bio-oil, syngas and bio-char production from biomass residues." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32706/.

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Design, development and assessment of a Fluidized Bed Reactor (FBR) is a very complex process, where enormous empirical correlations; charts and graphs; lot of parameters, assumptions, unit operations are involved, straight forward design equations and design data are limited, and generally the operation of the system requires many adjustments. The improved design of FBR with high coefficient of performance (COP), low energy consumption, high yield and environmentally friendly (low emission) is the target. The scope of the study is to design and fabrication of a lab scale fluidized bed fast pyrolysis system with throughput capacity of 1 kg of dry biomass per hour which includes a bubbling fluidized bed reactor, 2 cyclone separators in series, 4 condensers in series operating between temperatures of 600-300; 300-200; 200-125 and 125-40˚C to selectively condense alkanes, phenols, aromatics, indene, methyl-indene, benzene, toluene, methyl–naphthalene, esters, acids, alcohols, ketones; 2 heaters (1 pre- and 1 primary), an auger feeder with hopper and controller, blowers and rig structure. A 3-D simulation was performed to facilitate the mounting of different unit operations, instruments and control panels with sufficient maintenance and manoeuvring accessibilities yet compact structure with low structural footprints. The rig is having the dimensions of 2204X2750X1100mm (L x H x W) and suitable for batch operation to produce about 650 gm bio-oil, 150 gm non-condensable and 200 gm bio-char from 1kg of dry biomass pyrolysis. The rig is manually operated, however the data acquisition and logging systems are digital and has provision of scrubbing exhaust gas, and an online analyser has been installed to measure and monitor lower hydrocarbons including hydrogen concentrations and Lower Explosive Limit (LEL) in the exhaust gas. Four types of biomass such as Empty fruit bunch (EFB), Urban tree shavings (UTS), Saw dust Broga (SDB) and Saw dust Semenyih (SDS) were pre-treated with aqueous acidic (H2SO4) and alkaline (NaOH) solutions to find the percentage of solids extraction with varying liquid-solid ratios, acid/alkali concentrations, reaction temperatures and retention time. For pyrolysis operation, UTS was selected among the four biomass samples with a set of pre-treatment parameters (4.81 wt. % H2SO4, 15:1 liquid-solid ratio, 4hr retention time, 70˚C, 100rpm agitation speed) that maximizes bio-oil production. Pyrolysis in a batch tubular furnace at 600˚C with nitrogen flowrate of 30 ml/min resulted in bio-oil yield of 39.43% and 27.67%, and char yield of 38.07% and 30.73% from raw and pre-treated UTS respectively. The semi-batch pyrolysis results were compared with biomass pyrolysis results from the batch pyrolysis rig operations. The catalytic upgrading of the bio-oil to liquid fuel in a batch reactor is ongoing research work. The contribution of this research can be summarised as the successful design, fabrication, testing and operation of a Fluidized Bed System to produce fuel from biomass in batch pyrolysis. Characterization of the feedstock to get the optimum operation condition of the designed FBR to get the best yield out of the system and evaluation of the performance characteristics (Mass and Energy Balance) of the system. Characterization of the products (bio-oil, bio-char and syngas) following standard methods having results comparable with literature.

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27

Qu, Yuanxu. "Life cycle water footprint analysis for the production of bioslurry fuels from fast pyrolysis of mallee biomass in Western Australia." Thesis, Qu, Yuanxu (2017) Life cycle water footprint analysis for the production of bioslurry fuels from fast pyrolysis of mallee biomass in Western Australia. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40481/.

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It is projected that, in 2029-2030, coal will continue as a dominant fuel and take up 64% of energy market of Australia, because it supplies cheap and secure electricity generation [1]. However, combustion of coal contributes to various emissions including CO2, SO2, particulate matter (PM) and other pollutants [1]. Therefore, renewable energy, especially biomass is believed to be a vital energy source for sustainable development in the foreseeable future [2]. For example, mallee eucalypts as a key second-generation bioenergy feedstock are widely planted in the wheatbelt region of the southwest of Western Australia (WA) (300-600 mm rainfall zone) [1, 3]. However, mallee, as a kind of lignocellulosic biomass, suffers from its low volumetric energy density (about 5 GJ/m3), high moisture content (about 50%) and poor grindability, which causes the high transport cost [2]. This is unaccepted for a long-distance transport of biomass [2]. Pyrolysis as a chemical process converts biomass to a high energy product like bioslurry that can significantly reduce the transport cost [2]. However, some reports indicated the water consumption of producing bioenergy is larger than the traditional fuel such as coal [4]. Therefore, it is necessary to trace the life cycle Water Footprint (WF) of certain bioenergy production processes from the cradle to the grave. This thesis evaluates the WF of a biomass supply chain and a bioslurry supply chain in the transport and conversion stages in WA. 30 shires having abundant mallee stems resources are selected as the mallee supplying area for the Muja power station C and D units (874 MW). Also, an ideal harvesting and transport model is designed to determine the location of every farm gate of every selected shire for measuring the distances from 286 farm gates to the Muja power station, pyrolysis plant A, and pyrolysis plant B. In addition, Pyrolysis plant A (157.3 dry tonnes/day) is sited on Dalwallinu and pyrolysis plant B (203 dry tonnes/day) is sited on Wickepin, converting biomass to bioslurry, and then transport the bioslurry to the Muja power station. The result shows the annual water consumption of the bioslurry supply chain is approximately 22 times that of the biomass supply chain. However, the cost, energy, and carbon footprint of bioslurry supply chain have been proved by previous reports from Curtin University, having an advantage over the biomass supply chain in WA [2, 5].

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28

Gulshan, Samina. "Fast Pyrolysis of Biomass in a Fluidized Bed for Production of Bio-oil and Upgradation by Ex-situ Catalytic Bed." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254895.

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Production of bio-oil from biomass is now becoming best substitute of fossil fuels in the transportation sector. Pyrolysis is one of the most promising route to produce bio-oil from biomass. However, bio-oil needs to be upgraded due to presence of high percentage of oxygenated compounds. Catalytic fast pyrolysis is a very efficient way to produce and upgrade the bio-oil either it is in-situ or Ex-situ arrangement. This study presents the experimental investigation of fast pyrolysis of lignocellulosic biomass by ex-situ catalytic upgradation. The whole process consists of four parts: biomass grinding and sieving, pyrolysis, ex-situ fixed bed and vapours quenching. The pyrolysis experiment has been performed with nitrogen with or without catalyst to investigate the yield of different products. The analysis of results shows that higher yield of gas is obtained from catalytic upgradation together with the low yield of oil. The more oxygen was removed into CO and CO2 from vapours due to more cracking reactions occurred on catalytic bed. The yield of oil was decreased in catalytic experiments, but it has relatively good energy content due to no water in viscous phase and low acid number. The char yield was same for non-catalytic and catalytic experiments. Framställning av bioolja från biomassa är ett av de bästa alternativen som kan ersätta fossilabränslen i transportsektorn. Pyrolys är en av de mest lovande teknologierna för att framställabioolja från biomassa. Bioolja behöver dock uppgraderas på grund av en hög andeloxygenerade föreningar. Katalytisk snabbpyrolys är en effektiv metod för att producera ochuppgradera sådan bioolja, antingen genom in-situ eller ex-situ processuppställning. Denna studie presenterar en experimentell undersökning av snabbpyrolys av lignocellulosiskbiomassa kombinerat med ex-situ katalytisk uppgradering. Processen består av fyra delar:förbereda lämplig partikelstorlek av biomassa, pyrolys, ex-situ fastbädd och kondensering avångor. Pyrolysexperiment har genomförts med vätgas med och utan katalysator för attundersöka utbytet av olika pyrolysprodukter. Resultaten visar att en katalytisk uppgraderingger en ökad andel gasprodukt samt ett lågt utbyte av olja. Stor andel syre avlägsnades från oljansom CO och CO2 genom krackningsreaktioner i den katalytiska bädden. Oljeutbytet var lägrevid katalytiska experiment, men visade ett lovande energivärde pga en minskad andel vattensamt ett lägre syratal. Utbytet av kol var detsamma för katalytiska och icke-katalytiskaexperiment.

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29

King, Brian William, and n/a. "An experimental investigation of the effects of mouthpiece control on alto saxophone tone in the student player." University of Canberra. Education, 1993. http://erl.canberra.edu.au./public/adt-AUC20060814.133145.

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Good tone is one of an alto saxophone player's greatest assets and consequently deserves high priority in training and pedagogy. The current pedagogical literature gives little attention to tone production on the saxophone. The mouthpiece is the link between the player and the saxophone. This study examined the effect of the normal mouthpiece pitch and the pitch range produced on the saxophone mouthpiece on alto saxophone tone quality . In this experimental study, recordings were made of forty-three student alto saxophone players who performed tasks consisting of three saxophone mouthpiece exercises and four short musical phrases on the saxophone. The tape recordings were used to provide a spectral analysis of the tone samples by Fast Fourier Transform Analysis, and to allow qualitative analysis by five expert judges. The judges used a saxophone listening profile to provide qualitative evaluation of the recordings. Cluster analysis produced three groups of subjects according to combinations of the mouthpiece pitch and range produced. The mean sustained mouthpiece pitch and mouthpiece range of the groups were: Cluster 1 - 790 Hz and 550 cents; Cluster 2 1023 Hz and 150 cents: and Cluster 3 - 820 Hz and 1203 cents. Analysis of variance was used to test for statistically significant differences between the clusters. Discriminant analysis was used to identify other variables which contributed to the formation of the three clusters. The quantitative analysis of both mouthpiece and saxophone tones provided no insight into the spectra of the student subjects. The qualitative analysis using bipolar descriptors provided valid criteria which could be applied consistently for the analysis of student saxophone tone. A Tonal Index was computed from the judges' ratings in order to test for differences in tone between the clusters. Analysis of variance tests showed significant differences in the tone produced by the clusters on both the mouthpiece and the saxophone. The tone produced by Cluster 3 was significantly different to that produced by Clusters 1 and 2 at the p < .05 level. Discriminant analysis identified the use of saxophone tone models (through comparative critical listening) and small group performance as significant predictor variables (at the p < .05 level) in the formation of the clusters. The results of this study suggest that tone production on the alto saxophone is improved through the development of control on the mouthpiece. It was concluded that routine practice with the mouthpiece can serve in the development of a flexible and responsive embouchure and oral cavity and that students need to develop a mental concept of saxophone tone as part of the development of tone production. Also, experience in small group performance needs to be sought and provided for saxophone students. Finally, this study focussed on an area of mouthpiece behaviour which can easily be included into any instructional design and monitored by teachers.

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30

Tsvetkova, Galina Valeryevna. "An autonomous long-term fast reactor system and the principal design limitations of the concept." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/36.

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The objectives of this dissertation were to find a principal domain of promising and technologically feasible reactor physics characteristics for a multi-purpose, modular-sized, lead-cooled, fast neutron spectrum reactor fueled with an advanced uranium-transuranic-nitride fuel and to determine the principal limitations for the design of an autonomous long-term multi-purpose fast reactor (ALM-FR) within the principal reactor physics characteristic domain. The objectives were accomplished by producing a conceptual design for an ALM-FR and by analysis of the potential ALM-FR performance characteristics. The ALM-FR design developed in this dissertation is based on the concept of a secure transportable autonomous reactor for hydrogen production (STAR-H2) and represents further refinement of the STAR-H2 concept towards an economical, proliferation-resistant, sustainable, multi-purpose nuclear energy system. The development of the ALM-FR design has been performed considering this reactor within the frame of the concept of a self-consistent nuclear energy system (SCNES) that satisfies virtually all of the requirements for future nuclear energy systems: efficient energy production, safety, self-feeding, non-proliferation, and radionuclide burning. The analysis takes into consideration a wide range of reactor design aspects including selection of technologically feasible fuels and structural materials, core configuration optimization, dynamics and safety of long-term operation on one fuel loading, and nuclear material non-proliferation. Plutonium and higher actinides are considered as essential components of an advanced fuel that maintains long-term operation. Flexibility of the ALM-FR with respect to fuel compositions is demonstrated acknowledging the principal limitations of the long-term burning of plutonium and higher actinides. To ensure consistency and accuracy, the modeling has been performed using state-of-the-art computer codes developed at Argonne National Laboratory. As a result of the computational analysis performed in this work, the ALM-FR design provides for the possibility of continuous operation during about 40 years on one fuel loading containing mixture of depleted uranium with plutonium and higher actinides. All reactor physics characteristics of the ALM-FR are kept within technological limits ensuring safety of ultra-long autonomous operation. The results obtained provide for identification of physical features of the ALM-FR that significantly influence flexibility of the design and its applications. The special emphasis is given to existing limitations on the utilization of higher actinides as a fuel component.

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31

Laesecke, Jan. "Production and characterization of biomass fast pyrolysis oil blends for combustion testing as drop-in fuel alternatives in a single cylinder diesel engine." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60409.

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This research sought to demonstrate the potential of biodiesel and softwood derived Fast Pyrolysis Oil (FPO) blends as an alternative low-carbon drop-in diesel fuel. FPO was supplied from an in-house fluidized bed reactor as well as a commercial source. Separate FPO-biodiesel blends from both FPO sources were prepared using initial volumetric ratios of 80:20 and 60:40 (biodiesel:FPO, by volume). Upon blending each performed volumetric ratio, mixing and a 24 hour settling period, two layers formed and the top, biodiesel-rich layers containing about 5 and 10 vol % FPO were decanted and characterized on the basis of a thermogravimetric analysis, viscosity, acid number, water content, elemental analysis, and heating value. Significant decreases in viscosity, acidity, and water content from the original FPO validated blending as means of extracting compounds suitable for use as fuels from pyrolytic liquids in biodiesel. A single cylinder, direct injection diesel engine was used to analyze the combustion performance of the FPO fuel blends against neat diesel and biodiesel. Fuel performance was characterized on the basis of a thermodynamic analysis and corresponding exhaust measurements for CO₂, CO, unburned hydrocarbons, particulate matter, and NOx. Two thermodynamic measurement campaigns were performed in order to provide insight into FPO fuel performance across various engine conditions. In addition to the thermodynamic measurements, in-cylinder high-speed photography was implemented to support the interpretation of thermodynamic combustion data. Engine testing revealed similar indicated efficiencies for biodiesel and diesel at all considered engine-operating modes, while blend fuels showed indicated efficiencies between 75 and 95% of diesel values. FPO fuels exhibited increased ignition delays and shorter combustion durations with greater FPO blend concentrations, though this could be partially compensated for using a pilot injection strategy. The longer ignition delays of the blend fuels resulted in overly lean regions of the cylinder, which produced largely premixed combustion events contributing to brake specific CO and uHC emissions up to 1.5 and 3.5 greater than diesel, respectively. Specific PM emissions were 41-62% lower for blend fuels than diesel. Both blends of in-house FPO showed similar PM emission performance, however at higher concentrations than low blend commercial fuel. Applied Science, Faculty of Graduate

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32

Hackett, Tara. "A Comparative Life Cycle Assessment of Denim Jeans and a Cotton T-Shirt: The Production of Fast Fashion Essential Items From Cradle to Gate." UKnowledge, 2015. http://uknowledge.uky.edu/mat_etds/9.

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As a result of harmful textile production, sustainability has become the movement by which the apparel industry explores solutions to improve procedures in fashion design to maintain a healthy environment. However, the issue is consumers trust the sustainability claims and marketing materials of apparel products at face value without knowing its environmental impact. The overall purpose of this research was to compare the environmental implications of widely produced and owned apparel products through a life cycle assessment approach. This life cycle assessment study examines key environmental impact categories of the materials and production phase (cradle to gate) of a pair of jeans and a cotton t-shirt. The specific purpose of this study was to identify if the production processes make a sustainable product at the point of purchase. Furthermore, this research study compares the environmental impacts of a denim jean and dyed cotton t-shirt utilizing the ReCipe 2008 LCA tool.

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33

Chaumba, Joseph A. "Opportunities for and constraints on crop production within Zimbabwe's fast-track resettlement programme: A Case Study of Fair Range Estate, Chiredzi District, South Eastern Zimbabwe." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9563_1181914396.

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The government of Zimbabwe started implementing its fast track resettlement programme in July 2000, the objective being to accelerate both land acquisition and land redistribution. This programme witnessed a massive movement of people from various localities into mainly large-scale commercial farms in search of agricultural land. Under this programme, people were settled under the A1 model (which involves villages and land use pattern similar to those found in communal areas) as well as the A2 model, which involves commercial farming. This study investigates, documents and analyses the opportunities and constraints currently being faced by newly resettled crop production farmers in one example of an A1 model resettlement project (Fair Ranch Estate in Masvingo Province). A questionnaire was used to gather data on livelihood sources, income, assets and also aspects of the associational life of crop production farmers. Seventy households were interviewed, and a number of key informant interviews were undertaken with both government officials and the local leadership. The greatest opportunity that A1 crop production farmers in Fair Range Estate experienced was the fact that they now have access to land that they can call their own, without having to go through the market to try to acquire such land. In terms of crop production, however, farmers in Fair Range Estate face a number of challenges and constraints: they lack adequate access to tillage and livestock the supply of inputs is inadequate generally negative socio economic conditions prevailing in the country have led to sharp increases in prices of all basic commodities, including inputs such as fertilisers and seeds they lack tenure security the amount of rainfall received in the area is generally not sufficient for crop production and many lack crop production skills. Measures to reverse this decline must include the availability of foreign currency to buy spare parts for tractors, rebuilding of the national herd, which was greatly affected by both drought and the disturbance of commercial agriculture as a result of the controversial land reform programme. Fuel should also become more readily available, and urgent policy measures be put in place to revamp institutional frameworks in the agricultural sector to make them more farmer-oriented.

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Kaddouri, Farah. "Développement de diagnostics avancés pour l'étude de la cinétique ultrarapide de production d'oxygène par décharge nanoseconde dans l'air à pression atmosphérique." Phd thesis, Ecole Centrale Paris, 2011. http://tel.archives-ouvertes.fr/tel-00649475.

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Un grand nombre d'applications de plasmas à pression atmosphérique sont en développement. Une obtention de plasma à haute réactivité chimique pour un faible coût énergétique est possible par l'utilisation de décharges nanosecondes répétitivement pulsées (DNRP).Cette recherche concerne plus particulièrement l'effet des NRPD en combustion assistée par plasma. Cette dernière permet l'utilisation de flammes pauvres, qui produisent moins de NOx et qui sont par conséquent moins polluantes.Pour comprendre les phénomènes physico-chimiques qui régissent les NRPD, différents diagnostiques optiques et mesures électriques ont étaient mis en place.L'efficacité de la combustion est très sensible à l'oxygène atomique (O). Nous avons présumé dans nos travaux que la production de cette oxygène ce faisant via un mécanisme a deux étapes où l'azote de l'air produis par impact électronique de l'azote excité aux états (A,B,C), qui réagis ensuite avec l'oxygène moléculaire donnant de l'oxygène atomique.Les densités d'états excités N2(B) et N2(C) on été déterminées par spectroscopie d'émission. L'état N2(A) est lui mesure par spectroscopie d'absorption en cavité résonnante. L'évolution de la concentration de l'oxygène atomique est déterminée par TALIF et on a noté jusqu'à 50% de dissociation de l'oxygène moléculaire en oxygène atomique. Des mesures résolues spatialement et temporellement ont été effectuées. L'élévation de la température du gaz dans la décharge a été établie. Des mesures électrique de tension et de courant ont permis l'estimation de l'énergie déposée par pulse.En résume ses mesures nous ont permis de mieux comprendre et de caractériser une DNRP dans l'air. Le fait que les temps de décroissance et les valeurs de l'évolution des concentrations des états excités de l'azote coïncident avec ceux de la production de l'oxygène atomique et que le gaz voit sa température s'élever de quelques centaines de degrés tendent à valider le mécanisme à deux étapes proposé.

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Rogers, John G. "A techno-economic assessment of the use of fast pyrolysis bio-oil from UK energy crops in the production of electricity and combined heat and power." Thesis, Aston University, 2009. http://publications.aston.ac.uk/15376/.

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This thesis investigates the cost of electricity generation using bio-oil produced by the fast pyrolysis of UK energy crops. The study covers cost from the farm to the generator’s terminals. The use of short rotation coppice willow and miscanthus as feedstocks was investigated. All costs and performance data have been taken from published papers, reports or web sites. Generation technologies are compared at scales where they have proved economic burning other fuels, rather than at a given size. A pyrolysis yield model was developed for a bubbling fluidised bed fast pyrolysis reactor from published data to predict bio-oil yields and pyrolysis plant energy demands. Generation using diesel engines, gas turbines in open and combined cycle (CCGT) operation and steam cycle plants was considered. The use of bio-oil storage to allow the pyrolysis and generation plants to operate independently of each other was investigated. The option of using diesel generators and open cycle gas turbines for combined heat and power was examined. The possible cost reductions that could be expected through learning if the technology is widely implemented were considered. It was found that none of the systems analysed would be viable without subsidy, but with the current Renewable Obligation Scheme CCGT plants in the 200 to 350 MWe range, super-critical coal fired boilers co-fired with bio-oil, and groups of diesel engine based CHP schemes supplied by a central pyrolysis plant would be viable. It was found that the cost would reduce with implementation and the planting of more energy crops but some subsidy would still be needed to make the plants viable.

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36

Kubis, Peter [Verfasser], Christoph [Akademischer Betreuer] Brabec, and Michael [Akademischer Betreuer] Schmidt. "Design and Development of Ultra-fast Laser Patterning Processes for the Production of Organic Photovoltaic Modules with High Geometric Fill Factor / Peter Kubiš. Gutachter: Christoph Brabec ; Michael Schmidt." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2014. http://d-nb.info/1065045808/34.

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Coplen, Amy Katherine Rose. ""Poverty Wages Are Not Fresh, Local, or Sustainable": Building Worker Power by Organizing Around (Re)production in Portland's "Sustainable" Food Industry." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5092.

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Although conscious consumers flock to sustainability-branded restaurants and grocery stores to "vote with their forks" for environmental sustainability and vibrant local economies, workers in these industries face the same poverty wages, discrimination, and exploitative labor practices that plague the food service and retail industries at large. Despite rapid growth and labor degradation, low-wage workers in these industries have largely been left behind by the mainstream labor movement and the alternative food movement. Whereas in the past, progressive social movements worked to alter power relations between labor and capital through collective action, today's mainstream labor movement focuses on servicing its dwindling membership and winning minimum wage increases through local ballot box measures and legislation. For its part, the alternative food movement focuses narrowly on achieving environmental sustainability through market-based mechanisms and consumption politics that do not adequately attend to the struggles of food chain workers. Through research conducted in partnership with the Burgerville Workers Union (BVWU) and the Industrial Workers of the World, I investigate three empirical research questions: 1) How do sustainability-branded institutions deploy values-based discourse and how does this relate to labor practices?, 2) How do worker-organizers understand and expose the contradictions of sustainability branding?, and 3) How do worker-organizers engage with social reproduction as a terrain of political struggle, and to what ends? I attend to these questions through activist scholarship aimed at informing my broad theoretical question: How might social reproduction "as discourse and practice" be marshaled to generate more inclusive organizing strategies, forge more just conceptions of sustainability, and build worker power? Drawing on over two years of ethnographic research, content analysis, and interviews with 48 worker-organizers involved in four labor organizing campaigns, I examine their efforts to build worker power through mutual aid programs, political education, and coalition politics. My analysis reveals that these strategies embody an inclusionary intersectional politics that prioritizes the needs of women, parents, and people of color, but that worker-organizers also face significant challenges. I demonstrate that organizing against neoliberal policies and practices requires moving beyond consumption politics and single-issue campaigns and deploying what I term (re)production politics which are fundamentally about how work is organized and how we care for society and the planet. Politicizing the labor, locations, and practices of social reproduction as landscapes of struggle, I conclude, offers an opportunity to build a broad class consciousness across interconnected issues and envision more liberatory ways of organizing social reproduction based on solidarity, mutuality, and interdependence.

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Rohrs, Werner. "The effect of product mix complexity in the FMCG industry, with specific focus on manufacturing." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/85165.

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Thesis (MBA)--Stellenbosch University, 2007. ENGLISH ABSTRACT: Product Mix Complexity is a very real issue in modern companies. As globalisation and competition increase, markets mature and the needs of individual consumers get ever more specific, the trend towards more product variety will grow. Product Mix refers to the full range of products that a company offers to its customers. Product Mix Complexity refers to the effect that this product variety has on organizational performance. Understanding and management of this problem is difficult due to the many organizational elements involved, the complicated relationship between these elements and the fact that the problem crosses functional organization boundaries. A company may choose to differentiate itself in the market by offering a broad product mix. To do this effectively the price that can be asked for an item must offset the additional costs brought on by this complexity. This balance between variety that drives sales, and the costs of the added complexity is at the core of the effective management of Product Mix Complexity. The effect of this complexity in manufacturing relates to the loss of scale efficiencies and the need for flexibility in operations. Due to the difficulty in understanding the complex effects of variety, company portfolios tend to proliferate, resulting in a very skewed spread of product contributions where a small % of products contribute a high proportion of company profits. Management processes that continuously evaluate the total profitability of their portfolios from a ‘cost of complexity’ point of view are needed. Cost accounting systems often do not accurately account for this cost of complexity. The effects of Product Mix Complexity are investigated in Cadbury South Africa. The business displays clear signs of having a classical ‘Pareto’ spread of products where a ‘long tail’ of small volume products add very little profit to the business. The Port Elizabeth factory is an above average complex plant within the Cadbury group. It was found that the cost allocation system employed by Cadbury is not accurately allocating costs to products and is thereby aggravating the proliferation of the Cadbury product portfolio. Potential savings by rationalizing the Cadbury product portfolio are identified. A number of recommendations to better manage the presence of Product Mix Complexity are made, both for the business as a whole and for manufacturing specifically. AFRIKAANSE OPSOMMING: Produkmengselkompleksiteit is alomteenwoordig in moderne besighede. Die neiging tot meer produkverskeidenheid groei namate globalisering, kompetisie en verbruikers se behoeftes na verskeidenheid toeneem. ‘Produkmengsel’ verwys na die volle reeks produkte wat ’n maatskappy aan die mark bied. ‘Produkmengselkompleksiteit’ verwys na die effek wat produkverskeidenheid het op die doeltreffendheid van ’n besigheid. Die probleem is moeilik om te definieer en te verstaan as gevolg van die baie besigheidselemente wat betrokke is, die komplekse verhoudinge tussen hierdie elemente en die multi-funksionele aard van die probleem. Vir strategiese redes wil ’n maatskappy soms ’n groot verskeidenheid produkte aanbied om hom te onderskei in die mark. Om hierdie strategie winsgewend te maak moet die prys wat behaal word opmaak vir die ekstra kostes wat aangegaan word om die breë verskeidenheid te kan aanbied. Die balans tussen die interne koste van verskeidenheid en die voordeel van die verskeidenheid is baie belangrik in die effektiewe bestuur van produkmengselkompleksiteit. Omdat die effek van verskeidenheid moeilik is om te definieer, neig maatskappye daarna om liewer te veel as te min produkte aan te bied. Die gevolg is dikwels ‘n ongebalanseerde distribusie van produkwinsgewendheid waar ’n klein persentasie produkte verantwoordelik is vir die oorgrote meerderheid van die wins. Bestuursprosesse wat produkportefeuljes vanuit ‘n kompleksiteitskoste oogpunt evalueer ontbreek dikwels. Produkkostemodelle neem ook dikwels nie hierdie koste akkuraat in ag nie. Die effek van produkmengselkompleksiteit in Cadbury Suid-Afrika word in hierdie studie ondersoek. Dit is duidelik dat Cadbury Suid-Afrika ’n klassieke ‘Pareto’ effek vertoon waar ’n lang stert van klein produkte baie min tot besigheidswins-gewendheid bydra. Die Port Elizabeth fabriek vertoon ook bogemiddelde kompleksiteit relatief tot ander Cadbury fabrieke. Kompleksiteitskostes word nie akkuraat toegedeel tot produkkostes nie, met die gevolg dat klein produkte aanhoudend tot die produkmengsel gevoeg word. Die potensiële besparings as gevolg van rasionalisasie van die produkportefeulje is bereken. Aanbevelings vir die beter bestuur van produkmengselkompleksiteit word gemaak vir die besigheid as ’n geheel en vir vervaardiging spesifiek.

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39

Mehta, Bhanvi. "The Formation of Pharmaceutical Co-crystals by Spray Drying. An Investigation into the Chemical and Physical Factors Affecting the Production of Pharmaceutical Co-crystals by Fast Evaporation and Spray Drying." Thesis, University of Bradford, 2016. http://hdl.handle.net/10454/14630.

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Crystal engineering study using spray dryer was performed for scale-up and rapid, continuous crystallisation of co-crystals from solution. The study emphasise on developing co-crystals of two structurally similar compounds, caffeine (CAF) and theophylline (THEO) with various di-carboxylic acids. The incongruently soluble pair of CAF and THEO with di-carboxylic acids acquires large solubility difference which is important to consider for its utility in product development. Based on previous assumption that maleic acid (MAL) elevates CAF’s solubility; solubility of the two similar compounds was tested in various dicarboxylic acids. Other solubility enhancement strategies such as introduction of surfactant and binary solvents were also scrutinised. A kinetically similar bench-scale technique, rotary evaporator (rotavap) was investigated as a pre-screening tool for the production of co-crystals via spray drying. Furthermore, various process parameters within the spray dryer were optimised to control the kinetic conditions which influence co-crystallisation and quality of the product. Another polymorphic co-crystal pair, CBZ (carbamazepine) and SAC (saccharin) was examined in various solvents and its degradation was evaluated over a period of few months. In this study, a two-step conversion of CBZ into its degradate was hypothesised. Rotavap delivered a true reflection of co-crystal favoured via spray drying apart from co-crystal pairs depicting polymorphism. Spray dryer offered a unique environment favouring metastable forms of co-crystals irrespective of the starting component stoichiometry; generating CAF:MAL 2:1. However, due to process limitation and solubility constraint, the impurity of CAF in CAF:MAL 2:1 co-crystals could not be abolished.

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40

Bergenwall, Bel E. "From Particle-Production Cross Sections to KERMA and Absorbed Dose for the Case 96 MeV n-12C Interactions." Doctoral thesis, Uppsala universitet, Institutionen för kärn- och partikelfysik, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4700.

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Neutron-carbon interactions have been studied with a focus on charged-particle production of relevance to radiation protection and medical applications, such as cancer therapy. The measurements have been performed using the particle-detection setup, MEDLEY, and the 96 MeV neutron beam at the The Svedberg Laboratory in Uppsala. Double-differential cross sections of inclusive charged-particle production are compared with recent calculations from models based on the GNASH code including direct, preequilibrium and compound processes. For protons, the shapes of the cross-section spectra are reasonably well described by the calculations. For the other particles- d, t, 3He and α- there are important discrepancies, in particular for 3He-ions and α-particles, concerning both shape and magnitude of the spectra. Using the new cross sections, partial as well as total KERMA coefficients have been determined. The coefficients have also been compared to previous experimental results and model calculations. The p, d and t KERMA coefficients are in good agreement with those from a previous measurement. For the helium isotopes, there are no previous measurements at this energy. The KERMA coefficients are considerably higher (by up to 30%) than those predicted by the calculations. The KERMA results indicate that protons and α -particles are the main contributors to the dose. A 6x6x6 cm3 carbon phantom, exposed to a broad and a pencil-like beam, is used for the computation of the absorbed doses deposited by these two particles in spheres of 1 μm in diameter, located at various positions in the phantom. The maximum doses are deposited at ~3 cm from the surface of neutron impact for protons and within 1 cm for α-particles. For the pencil beam, deposited doses are spread over regions of ~1.5 cm and ~300 μm transverse to the beam for protons and α-particles, respectively. The results are consistent with previous integral measurements at lower energies.

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41

Lueb, Mario [Verfasser], Hans-Otto [Akademischer Betreuer] Günther, and Christian [Akademischer Betreuer] Almeder. "Modeling production sequences in the fast moving consumer goods industry : the impact of changeover structure in integrated lot-sizing and scheduling / Mario Lueb. Gutachter: Hans-Otto Günther ; Christian Almeder. Betreuer: Hans-Otto Günther." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065665989/34.

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42

Bergenwall, Bel E. "From Particle-Production Cross Sections to KERMA and Absorbed Dose for the Case 96 MeV n-¹²C Interactions." Doctoral thesis, Uppsala University, Department of Nuclear and Particle Physics, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4700.

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Neutron-carbon interactions have been studied with a focus on charged-particle production of relevance to radiation protection and medical applications, such as cancer therapy. The measurements have been performed using the particle-detection setup, MEDLEY, and the 96 MeV neutron beam at the The Svedberg Laboratory in Uppsala.Double-differential cross sections of inclusive charged-particle production are compared with recent calculations from models based on the GNASH code including direct, preequilibrium and compound processes. For protons, the shapes of the cross-section spectra are reasonably well described by the calculations. For the other particles- d, t, 3He and α- there are important discrepancies, in particular for 3He-ions and α-particles, concerning both shape and magnitude of the spectra.Using the new cross sections, partial as well as total KERMA coefficients have been determined. The coefficients have also been compared to previous experimental results and model calculations. The p, d and t KERMA coefficients are in good agreement with those from a previous measurement. For the helium isotopes, there are no previous measurements at this energy. The KERMA coefficients are considerably higher (by up to 30%) than those predicted by the calculations.The KERMA results indicate that protons and α -particles are the main contributors to the dose. A 6x6x6 cm3 carbon phantom, exposed to a broad and a pencil-like beam, is used for the computation of the absorbed doses deposited by these two particles in spheres of 1 μm in diameter, located at various positions in the phantom. The maximum doses are deposited at ~3 cm from the surface of neutron impact for protons and within 1 cm for α-particles. For the pencil beam, deposited doses are spread over regions of ~1.5 cm and ~300 μm transverse to the beam for protons and α-particles, respectively. The results are consistent with previous integral measurements at lower energies.

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43

Mbairodbbee, Njegollimi. "L'école et la production au Burkina Faso." Paris 5, 1987. http://www.theses.fr/1987PA05H118.

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Introduite et conduite dans des conditions sérieuses de préparation, d'organisation de gestion et de responsabilisation des élèves, principaux intéressés, la pratique des activités productives a l'école est l'un des moyens surs d'accentuer l'acquisition des connaissances chez par les élèves, de favoriser l'autofinancement de l'école, et de promouvoir l'intégration de l'école et l'adaptation de son produit (élèves en sortants) à l'environnement. Conditions de succès : profonds changements dans les structures sociales et mobilisation générale de la société, sous l'impulsion ordonnée de l'état Being introduces and managed in the good and serious conditions of the preparation, the planning, the administration and the liability for pupils (who are the most concerned) the practice of the productive actions at school is one of certain means to increase the intellectual attainments in by the pupils. This sure means favors playing back of school profits and promotes school's integration and the adaptation of its products (the pupils in their last term) to the environment. The conditions of success are deep changes in the social structures and the general call (mobilization) of the society on the ordinated pulse of state

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44

Mbairodbbee, Njegollimi. "L'Ecole et la production au Burkina Faso." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37616191f.

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45

Tanti, Miriam Helen Maks. "Applying Slow to ICT-rich education: A vision for the ‘long now’." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14329.

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In everyday public and policy discourse, Information and Communication Technology (ICT) is strongly associated with speed – with rapidly accelerating innovation in products and services, with shortening lifecycles for products and careers, and with unpredictable changes in global flows of capital, goods and risk. This study explores a different set of ideas – ideas associated with Slow – slow food, slow cities, slow design, etc. A motivation behind the study is to reframe the way we think about ICT in Education – to question the strength of the connections between ICT and ‘fast’ and to explore what Slow ideas might look like in alternative conceptions of ICT and Education. The thesis carries out this exploration by weaving together strands of philosophical and educational inquiry. It explores meanings of Slow in thinking about education, and life more broadly. It uncovers and interprets four themes: Slow as a state of mind; reconceptualising time; valuing process and the connectedness of self, people and place. It uses phenomenology to study lived experiences of Slow and of ICT, in education and beyond. The research reported in the thesis falls into three phases. In the first phase, I interviewed a range of people who are advocates of Slow – to find out more than can be found in their writings alone about what Slow means to them, and to tease out some connections in their thinking about Slow and their thinking about Education and/or ICT. (Only one of these people was formally involved in Education.) The four common themes mentioned above began to appear in my analysis of these interviews. In Phase Two, I conducted in-depth interviews with people who have recent, in-depth experience of working with ICT in Education. Analysis of these interviews was coupled with philosophical reflections on aspects of Slow to illuminate an ontology of Slow in the educational context. I designed and produced an artefact to capture what was emerging as the essence of Slow – in relation to Education. This artefact – a simple but carefully designed document – was used as a focal point and stimulus for a small group discussion: the centrepiece of Phase Three of the research. This focus group consisted of experienced educators and their reflections on the Slow ideas, my practical aims and their own professional experiences produced some further insights into the challenges of applying Slow ideas in rethinking ICT in Education.

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46

Belem, Pegda Célestin. "Coton et systèmes de production dans l'ouest du Burkina Faso." Montpellier 3, 1985. http://www.theses.fr/1985MON30057.

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47

GALIZIA, PIETRO. "Production and morphological and microstructural characterization of bulk composites or thick films for the study of multiphysics interactions." Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2674672.

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The surge of interest in multifunctional materials over the past 15 years has been driven by their fascinating physical properties and huge potential for technological applications such as sensors, microwave devices, energy harvesting, photovoltaic technologies, solid-state refrigeration, and data storage recording technologies. Among the others, magnetoelectric multiferroic composites are a special class of advanced solid-state compounds with coupled ferromagnetic and ferroelectric ferroic orders which allow to perform more than one task by combining electronic, magnetic and mechanical properties into a single device component. The production and characterization of lead zirconate titanate (PZT)- cobalt ferrite composites was the main topic of the thesis. During the PhD activity different ceramic processing and characterization technologies were studied and involved in order to optimize the produced materials as a function of the final microstructural and functional properties. The synthesis of cobalt ferrite (CF) and niobium-doped lead zirconate titanate (PZTN) powders by solid state reaction method and sol-gel technique, to control the particle size distributions and their microstructural and functional properties through calcination and milling treatments has been addressed first, followed by the mixing of the PZT and CF powders to produce particulate composites. The dispersion of PZT and CF in a liquid media, to produce layered composites by depositing the particles by electrophoretic deposition was an objective of the work as well. Key issues such as the lead loss during the sintering of PZTN-CF composites and the reaction between CF and titania have been addressed and have resulted in improvements in the sintering and characterization techniques leading to the production of fully dense PZTN-CF dual-particulate composites. In particular, the optimized sintering parameters have configured a new paradigm of ceramic sintering, which has been called quite-fast sintering, in respect to the traditional one, and the study of the PbO loss has led to propose an equation to calculate the PbO loss through XRD analysis. Further important achieved results were: the production of nanocobalt ferrite particles by multi-step milling, the correlation between the spin-canting angle with the microstrain and the average crystallite size of nanocobalt ferrite particles, the understanding of the CF growth mechanisms, the extension of the Globus model from small ferromagnetic grains “having no defect inside” to multiparallel-twinned overgrown ones, the understanding of heating rate effect on the interface nucleation onset of the anatase-to-rutile transformation and the anatase particle size, and the reaction products between CF and rutile at 1200 °C at the variation of CF/rutile ratio.

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MAZZA, MARIO. "Global markets and supply customization in urban trasportation system." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/40116.

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The increasing world’s population, mainly concentrated in urban areas, is leading to an increasing demand for transport services, which is an inescapable consequence of global trends. Indeed, evolving demographic, social and economic trends create dynamic demand for mobility by individuals, companies and governments. Developing and emerging countries manifest several needs mainly related to commuting mobility from home to work, infrastructures, production plants and machinery, housing, economies of scale and modern technologies. In these countries, passenger demand is growing due to increased separation between accommodation and work and, as a consequence, traffic in urban and metropolitan areas, as in surrounding regions, is progressively congested. On the contrary, networks and interactions between people for the creation of new knowledge characterize developed countries and the needs are referable to mobility during the working time, for shopping and for social purposes. More in general, cities, big and small, are faced by several challenges in health, mobility, social development, security, water and energy resource management, but nowadays their survival and sustainability depend more and more on a reliable and worthwhile transportation system. Indeed, especially in fast growing context, the issue of mobility and transport is the key challenge facing cities now and in future. In this context, cities represent the engine of the urban transportation systems industry and the present dissertation focuses on the response of global suppliers of rail-based solutions to increasing need of mobility. In global markets, where the time is considered a decisive factor (time-based competition) and the competitive space become broaden and dynamic (market-space management), the urban transportation systems suppliers could compete and survive only adopting a Market-Driven approach. The customization and the adaptation of the transportation systems to the requirements of several clients represent a primary challenge for global market’s suppliers, which need to organize their operations on flexibility and on non-competitive structures, such as networks, taking into account sub-suppliers, clients and even competitors. In borderless competitive arena besides Europe and United States, new markets are increasingly drawing the attention of global suppliers and in this dissertation through a field research has been examined the situation of the Saudi Arabia.

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Belem, Benido Claude Davy. "Analyse des déterminants de l'adoption des bonnes pratiques de production de l'anacarde au Burkina Faso." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27700.

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Au Burkina Faso, 86% de la population active travaille dans l’agriculture. Toutefois, dans un contexte de démographie galopante et de manque d’investissements, cette agriculture a du mal à couvrir les besoins des populations. La diffusion et l’adoption de techniques améliorées de production sont à même d’inverser la tendance en permettant une intensification durable des productions. Malheureusement, les résultats obtenus par les initiatives de vulgarisation des technologies n’ont pas toujours été satisfaisants. Cette réalité est doublement vraie dans le cas des systèmes agroforestiers à base d’anacardiers ; systèmes nouveaux dont l’expansion s’est faite par les producteurs eux-mêmes sans aucune assistance technique. Il est donc indispensable d’identifier les déterminants de l’adoption des technologies diffusées. C’est dans ce but qu’une étude a été réalisée dans les régions des Cascades, des Hauts-Bassins et du Sud-Ouest du Burkina Faso auprès de 68 ménages producteurs d’anacarde afin de démontrer la pertinence de ces pratiques et d’identifier les déterminants de leur adoption en vue de formuler des recommandations pour réduire les contraintes majeures à celle-ci. L’étude a permis de montrer que l’application des bonnes pratiques de production permettait d’augmenter le rendement de l’anacardier. En outre, le facteur démographique « niveau d’éducation » du chef de ménage ainsi que les facteurs socioéconomiques notamment le prix obtenu à la vente et l’appartenance à une organisation paysanne ont une influence sur la probabilité d’adoption. In Burkina Faso, 86% of the active population works in agriculture. However, in a context of rapid population growth and lack of investment, that agriculture is struggling to meet the needs of populations. Dissemination and adoption of improved production techniques are able to reverse the trend by enabling sustainable intensification of production. Unfortunately, the performances of the technology outreach initiatives have not always been up to expectations. This reality is doubly true in the case of cashew-based agroforestry systems; these new systems whose expansion was carried out by the producers themselves without any technical assistance. It is therefore essential to identify the determinants of adoption of disseminated technologies. It is for this purpose that a study was conducted in the Cascades, Hauts-Bassins and Southwest regions of Burkina Faso among 68 cashew producing households to demonstrate the relevance of these practices and identify the determinants of their adoption in order to make recommendations to reduce major constraints. The study showed that the application of good production practices made it possible to increase the yield of the cashew tree. Moreover, the demographic factor "level of education" of the head of household and socioeconomic factors including the price obtained on the sale and membership of a farmer’s organization influence the likelihood of adoption.

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50

Asante, Emmanuel A. "Biochemical genetics of lipid metabolism in chickens and mice." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/11520.

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Dissertations / Theses on the topic 'Fast production'

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