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1
Féret, Sophie. "Statuettes en terre cuite de l'époque hellénistique en Italie : productions et variations." Thesis, Paris 1, 2018. http://www.theses.fr/2018PA01H095.
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Le moulage en terre cuite est un procédé de fabrication qui permet de reproduire mécaniquement des objets, à l’aide de matrices. Aussi, en tant que procédé technique, la coroplathie est un exemple de fabrication et de diffusion d’images en nombre.Ma recherche est centrée sur la construction d’une typologie des statuettes en terre cuite de l’époque hellénistique, et principalement celles qui datent des IIIe et IIe siècles av. n.è. en Italie.Celles-ci se caractérisent par un renouvellement iconographique des figurines génériques, sans attribut, dont les plus emblématiques sont les représentations de femmes drapées, appelées aussi « tanagréennes ». En effet, à partir du milieu du XIXe siècle, avec l’apparition sur le marché de l’art des figurines de Tanagra (vers 1870) et de Myrina (vers 1880), le sujet a commencé à attirer l’attention des amateurs d’antiquités puis des scientifiques. Longtemps collectionnées pour elles-mêmes, ces statuettes ont souvent été désolidarisées de leurs environnements archéologiques. En Italie, c’est en grande partie par des études rétrospectives des statuettes conservées dans les musées qu’on parvient aujourd’hui à reconstituer des assemblages et des contextes de découverte (votif ou funéraire). La documentation ayant servi de matière première à cette thèse est disparate. Elle est constituée de catalogues d’objets et de notices de sites éparses dans lesquelles les statuettes sont souvent sous-exploitées. C’est toute la difficulté de cette démarche : ces figurines en terre cuite, à la fois nombreuses, répétitives et souvent fragmentaires suscitent peu d’engouement ; la dynamique de recherche s’attardant davantage sur des lots d’objets mieux conservés ou identifiés. Dans un certain sens, mon travail tente de revaloriser le multiple tant du point de vue de l’artisanat que des usages de ces statuettes dans leurs matérialités religieuses.Le terrain d’enquête de cette étude est celui de l’Italie hellénistique, indépendamment des contextes culturels (italiques, grecs, étrusques, romains) dans lesquels l’historiographie a parfois eu tendance à enfermer la petite plastique en terre cuite. En dépit de leur nombre et de leur diversité, ou plus exactement en raison de ces facteurs, ces figurines restent assez mal connues.Dans ma démarche, j’ai tenté d’échapper aux classements iconographiques et techniques habituels. Ces types tanagréens, largement constitués de figurines féminines drapées mais aussi de quelques sujets mythologiques (Eros, Aphrodite, Athéna, Hermès…) qui par des jeux d’attributs superposés personnalisent ces figurines, ont été observés et analysés en fonction de leur forme et présentés selon une typologie morphologique. Celle-ci a été conçue dans la perspective de proposer une nouvelle grille de lecture et d’interprétation afin de construire des instruments de recherche mieux à même de s’adapter à ces objets dépourvus d’apparentes significations, enchevêtrés dans une sérialité des formes d’où émergent des singularités. La forme et ses variations sont au cœur du sujet, donnant lieu à des développements sur les principales échelles de production de ces figurines et sur l’interprétation des images qu’elles ont véhiculées en fonction de leur environnement topographique, historique et culturelTerracotta casting is a process of manufacturing that allows the mass production of objects with the help of molds. As a technical process, coroplasty is an example of mass production and diffusion of images.My research is focusing on building a typology for terracotta figurines of the Hellenistic era, more specifically the ones dating back to the 3rd and 2nd Centuries BC in Italy. These generic figurines, with no specific characteristics, feature a renewal in statuette iconography. The most emblematic ones usually represent women wrapped in veils, also called Tanagra figurines.Around the middle of the 19th century, with the apparition of figurines from Tanagra (circa 1870) and Myrina (circa 1880) on the art market, the statuettes began to catch the attention of connoisseurs, then scientists. Collected for themselves for a long time, these figurines have often been torn apart from their archeological environment. In Italy, thanks in great part to a retrospective study of the figurines preserved in museums, we are able to re-establish connections with groups and contexts of discoveries (votive or funerary figurines).The materials gathered for the documentation of this thesis are heterogeneous. It consists of artwork catalogues and notes from various sites where the figurines are often underexposed. The main complexity of this research follows thus: the terracotta figurines, both abundant and repetitive, often incomplete, arouse little enthusiasm; all the energy in research usually focuses mostly on the group of objects best preserved or identified. In a way, my work tries to reassert the value of numbers, as much from the point of view of handicraft as from the different religious functions of the figurines.Italy during the Hellenistic era is the field of investigation for this research, irrespective of cultural context (Italic, Greek, Etruscan or Roman) from which sometimes historiography has a tendency to confine small terracotta figures. Despite their number and variety, or rather because of them, these figurines remain largely ignored. My approach tries to break free from the usual iconographic typologies and technical classifications. I tried to observe and analyze the Tanagra figurines – mostly consisting of veiled feminine silhouettes, but also including some mythologicaltopics (Eros, Aphrodite, Athena, Hermes…) personalized through an array of superimposed attributes – taking into account their shape, and presenting them according to a morphological typology. This typology has been created in the prospect of offering a new frame of reference and interpretation, in order to build tools of research better fitted to these figurines, all lacking in apparent meaning, entangled in the serialization of its shapes, from which sometimes uniqueness emerge. The form and its variations are at the heart of the topic, leading to developments on main production scales, or on the interpretation of the images they conveyed depending on their topographical, historical and cultural environment
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Costa, Ana Sofia Vicente. "Seasonal variations in the effect of structural complexity of olive productions systems on bat activity: implications for natural pest control services." Master's thesis, Universidade de Évora, 2018. http://hdl.handle.net/10174/24445.
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Agricultural landscapes have suffered drastic changes as a consequence of management intensification, leading to a decline in biodiversity, specially in Mediterranean olive farms. Among others, homogenization affects the activity levels of bats, an important component of agricultural ecosystems by acting as biocontrol agents against olive pests. To understand how seasonal variations affects bat occurrence and the biocontrol services they provide, we sampled olive groves with different structural complexities over three seasons, coinciding with the peak activity of Prays oleae, one of the major pests of olive production systems. We found strong differences in the response of bats to the structural complexity of olive production systems, being these species-specific and strongly season-dependent. Thus, our results suggest that habitat heterogeneity is of great importance for bat activity, implying that structurally-complex agricultural landscapes could promote higher natural pest control services provided by bats; Variações sazonais no efeito da complexidade estrutural em olivais com diferentes sistemas de produção na atividade de morcegos: implicações para os serviços de controlo natural de pragas
Resumo:
As paisagens agrícolas sofreram drásticas mudanças por consequência da intensificação da gestão, levando ao declínio da biodiversidade, especialmente em olivais mediterrânicos. Entre outros, a homogeneização afeta os níveis de atividade dos morcegos, os quais apresentam elevada importância nos ecossistemas agrícolas pela sua capacidade de controlo natural de pragas. Para compreender como as variações sazonais afetam a ocorrência destes nos olivais, amostrámos olivais com diferentes complexidades estruturais em três estações, coincidindo com o pico de atividade de Prays oleae, uma das principais pragas dos olivais, para investigar se morcegos poderão atuar no seu controlo. Foram encontradas diferenças nas respostas dos morcegos em relação à complexidade estrutural dos olivais, sendo estas dependentes de cada espécie e da estação. Assim, os resultados sugerem que a heterogeneidade do habitat apresenta grande importância na atividade dos morcegos, implicando que paisagens agrícolas estruturalmente complexas poderão promover serviços de controlo natural de pragas fornecidos pelos morcegos.
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Cazals, Nathalie. "Constantes et variations des traits techniques et économiques entre le magdalénien inférieur et moyen : analyse des productions lithiques du nord de la Péninsule ibérique." Paris 1, 2000. http://www.theses.fr/2000PA010584.
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Cette étude part de l'intention d'identifier les particularités techniques et économiques des premières phases du magdalénien. Ainsi ce travail prétend apporter de nouveaux éléments pour caractériser les mécanismes évolutifs durant cette période. Pour cela, la corniche cantabrique est un terrain des plus adaptés en raison de la densité des sites magdaléniens mais aussi parce que les premiers moments de cette culture y sont particulièrement bien représentés. Notre analyse se veut une discussion sur la signification chronologique et la dimension géographique des phases "inferieure" et "moyenne" du magdalénien. Ce travail s'appuie dans un premier temps sur l'analyse technologique des industries lithiques (volume II) des séries sur lesquelles repose la structuration du magdalénien cantabrique: Las Caldas (Asturies) ; Rascano (Cantabres) ; Erralla (Guipuzcoa) ; Berroberria et Abauntz (Navarre). Les résultats obtenus sont ensuite confrontés selon un double axe comparatif à la fois diachronique et synchronique (volume I) afin d'interpréter la variabilité de ces industries. Ainsi, cette étude aboutit à l'individualisation des traits techniques et économiques qui définissent deux ensembles chronologiques et tente d'interpréter les variations enregistrées au sein des deux périodes. L'axe diachronique est toutefois privilégié même si l'interprétation de la variabilité synchrone s'effectue en ouvrant le champ de comparaison vers le Portugal, le pourtour méditerranéen, et l'ensemble Gironde-Périgord. L'analyse des industries lithiques nous conduit à établir les relations d'ordre technique et économique qui existent entre le badegoulien et le magdalénien "inférieur" et entre le magdalénien "inférieur" et le magdalénien "moyen" dans le sud-ouest de l'Europe.
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Dobeš, Radim. "Řešení pro odchylkovou analýzu nákladů ve výrobní společnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2021. http://www.nusl.cz/ntk/nusl-444622.
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At the very beginning of the diploma thesis, we introduce the reader to the issues of BI and controlling of manufacturing companies. Subsequently, we perform an analysis and evaluation of the current state of the selected manufacturing company in terms of variations in production. Then we use MSSQL server and SSAS to create a controlling model. The company will be able to unambiguously and quickly identify weaknesses in production and quickly eliminate them. Finally, we evaluate the real benefits of this project for the company.
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Salama, Yves. "Variations stochastiques des flux en production industrielle /." [S.l.] : [s.n.], 1998. http://library.epfl.ch/theses/?nr=1871.
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Månsson, Lotta. "Capturing Variation in Welding : A method to map variation in welding production, creating a basis for production improvements." Thesis, Karlstads universitet, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-74251.
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Weld quality is essential when manufacturing fatigue-loaded structures. Defective welds are problematic, causing increased lead times, repairs and breakdowns. Over- processing as a result of unnecessary safety margins and poor quality is another issue, leading to a more expensive process and heavier products. Knowledge about what variation in weld quality can be expected in the process enables more efficient problem solving and use of resources. Reduced variation equals increased quality. Consequently, reduced variation is both a manufacturer and customer gain. This thesis studies in what way variation in welding production can be mapped and presented, to guide towards the right improvement actions. A literature study addresses welding, weld quality, measurement methods and variation. Two empirical studies using laser scanning equipment along with staff interviews will then be conducted to develop the method to capture variation in welding. In the journey towards machine learning and elimination of operator decisions, knowledge and understanding of variation in the process is necessary. Concrete results of the empirical studies gave new and valuable information to the company. Further, the method to map, analyse and display variation was believed to be useful in several ways, both at the case company but also at other plants. The results show that knowledge about variation could have a large financial effect. By identifying the areas of over-processing and deficient quality, the process can be optimized to increase productivity. While technical issues such as equipment to collect data can be barriers, soft issues like competence, a common understanding, and visualisation of variation seem just as essential.
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Ahmad, Salman. "Kvalitets variations analys och Produktions anpassning." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-23561.
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This study aims to research variation at a startup company and to understand what methods are necessary to root out and eliminate quality issues. The study is conducted at Biotech AB which is a producer of Bio-instruments as well as bio-ingredients that are produced on site for customers. The company has been concerned with the amount of variation in internal quality coming from the production and the purpose of this study is to find what is causing the variations and what preventative actions need to be taken. This study has been a mix between a quantitative and a qualitative study with its base being around the records of errors given through quality logs. Several interviews were made as well as observations in working procedures and working instructions. The results showed that five major issues were causing the most concern and unnecessary cycles in production, namely featured parts and human error also cause these variations. The interviews indicated that processes need to be managed better and faster due to the rapid pace of the company growth. They also indicate that the communication doesn't always work and needs to flow freely in both directions. The level of waste is quite high in forms of physical waste and time wasted due to cycles in production. Lean thinking needs to be implemented and 5s needs to be made aware of to give everyone a quality and waste-free working ethic from the ground up. Many of these issues could be solved by implementing a quality perspective by giving constant feedback according to TQM.
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Johansson, My Ngoc, and Hasbani Salwa Al. "Minimization of Output Variation in Mass Customized Production." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-38410.
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During the past decades, there have been an acceleration of customers’ needs of customized products. This have pressured many companies in offering customized products in order to reach customer satisfaction and keep growing and expanding their market share. Nowadays the competitive pressure between companies with the same product segment is increasing and the market requirements are changing rapidly. To handle this competition, many manufacturing companies are focusing on mass customized production. However, mass customization has been a topic of interest for many researchers. The focus has been in studying and understanding the complexity and the constrains that a company encounter when dealing with mass customized production in mostly the automotive industry. One of the constrains that have been less highlighted by researchers were the effects that mass customized production has on the output variation of production lines. Therefore, the purpose of this thesis is to investigate how to minimize output variations in mass customized production within assembly lines. To do that the researchers focused on studying the output variation in whitegoods industry instead of the automotive industry that captures most of the existing research. The study includes two main research questions. The first question was to identify the factors that affect the output variation in mass customized production. While the second question was to identify applicable solutions that can be used to stabilize the output. To ensure the reliability and validity of the research findings, the researchers used multiple case study combined with literature reviews. To answer the research questions several data collection techniques were used in the multiple case study conducted on two lines. Those data collection techniques were participating observations, document reviews, a semi-structured interview and many conversations with the affected persons. The findings from the case study for research question one showed consistency with the theories described in the theoretical background. This was evident because similar problems when it comes to output variations were defined in the theories. One problem was about the simplification of assembly line balancing problem that was evident in both case studies. This was an effect of the missing product family classification which created a high output variation because of the use of only one line balancing for all product variants. Another problem identified included functionality problems of machines because of performing wrong assembly or the use of the wrong component. There was as well the problem of missing or delayed components which was an effect of the lack of structure in the material picking and the deliveries performed for both lines. A combination of those factors created the experienced output variation on both lines. To deal with those problems and minimize the output variation, a solution approach was defined in the second research question. This approach was created together with the case company with the help of the theoretical background and it presents several steps to follow when attacking and resolving similar problems as presented above. The most important conclusion of this thesis is that, when dealing with output variation in mass customized production where people are performing the assembly, it is essential to provide the right conditions for them to ensure that they have the right knowledge base to perform the requested assembly.
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Renon, Jean-Pierre. "Le zooplancton des milieux recifo-lagonaires de polynesie : variations temporelles, variations spatiales et bilan de production et d'echanges." Orléans, 1989. http://www.theses.fr/1989ORLE2053.
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Pour les communautes recifales dominees par les coraux et les poissons, le zooplancton constitue un potentiel nutritif insuffisamment etudie et source de controverses. La presente etude situe le zooplancton dans l'ecosysteme recifo-lagonaire et pose le probleme des limites de ce dernier. Les variations de composition et d'abondance du plancton de ces milieux sont etudiees dans le temps et dans l'espace a l'aide de filets et de pieges a emergence; les recherches concernent cinq lagons differant par leur degre d'ouverture sur l'ocean. Dans le temps, les variations nycthemerales depassent en ampleur les variations lunaires et les variations annuelles; elles constituent un trait caracteristique du plancton de ces milieux, particulierement dans les zones soumises a un fort hydrodynamisme. Dans l'espace, l'abondance et la repartition des organismes varient avec le degre d'ouverture des lagons; deux types d'heterogeneite se rencontrent: l'un est lie a l'hydrodynamisme de surface, l'autre a la vitesse de renouvellement de l'eau des lagons. L'etude des transferts planctoniques entre l'ocean et le lagon, d'une part dans un lagon de recif-bariere, d'autre part dans un lagon d'atoll montre, au terme des bilans, que le premier est importateur et le second exportateur; l'inclusion de la pente externe du recif dans l'ensemble recifo-lagonaire est necessaire pour comprendre ce bilan et ceci ouvre des perspectives nouvelles sur la structure et le fonctionnement de ces ecosystemes coralliens
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Ibrahim, Kadhim Mohammad. "Production of variation in salt tolerance in ornamental plants." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305403.
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Johnson, Dawn Lee. "Sound production in longear sunfish (Lepomis megalotis) : acoustic behavior and geographic variation /." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037507.
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Chazal, Marie. "Calcul des variations en économie et en finance : planification de production et gestion de stocks, bornes sur les prix d'options." Paris 9, 2003. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=2003PA090051.
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Pettersson, Maria, and Maja Truedsson. "Hantering av variation i en tillverkningsprocess." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-53471.
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Ökad konkurrens inom fordonsindustrin leder till större produktdifferentiering för att möta kundernas krav. Detta medför ökad variation i produktspecifikationer vilket tillverkande företag måste finna metoder för att hantera. Syftet med denna studie var att skapa en metod för hantering av produktvariation för att kunna minimera balanseringsförluster i form av kvalitetsavvikelser och stopptid i produktionen. En metod utvecklades utifrån fallföretagets förutsättningar och grundades på ett förbättringsprojekt samt från observationer från ett studiebesök i en annan verkstad hos fallföretaget. Variationshanteringsmetoden testades i en avgränsad del av produktionen i två etapper. Resultatet av testen visade på minskat antal kvalitetsavvikelser och mindre stopptid. Implementering av metoden låg utanför ramen av detta arbete, så avslutningsvis presenterades rekommendationer för implementering av metoden.
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O'Haire, Tom. "The production of ultrafine fibres using variations of the centrifugal spinning technique." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10484/.
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Centrifugal spinning uses high speed spinneret rotation to generate and elongate jets of polymeric material in to fine fibres. Variations of this basic technology has been used to form ultrafine fibres from: polypropylene (PP), ubiquitous in the nonwovens industry and a key material for nonwovens; polycaprolactone (PCL), a biocompatible polymer used previously as a biological scaffold; and polyvinylpyrrolidone with 1-triacontane (PVP/TA), a copolymer found in the cosmetics industry. This work demonstrated the melt centrifugal spinning of PP into sub-micron fibres ≤ 500 nm in diameter, and PCL fibres ≤900 nm in diameter. The influences of material properties and processing conditions on the fibre and webs properties were investigated and relationships established. For melt spinning, increasing the rotational speed will reduce the average fibre diameter and when solution spinning PCL a binary solvent produced finer fibres with increased surface textures. The spinning of PVP/TA into fibres demonstrated in this work has been previously unreported. PVP/TA fibres were created by centrifugal spinning at low temperatures were as fine as 1.5 µm on average. These fibres were used as an adsorbent and showed an affinity for the capture and retention of disperse dyes and hydrocarbons on the fibre surface. Carbon nanotube composite fibres were created by dispersing the nanotubes in both PP and PCL polymers using ultrasonic waves. The addition of carbon nanotubes significantly increased the level of beading during spinning in both PP and PCL as their presence causing an increase in Rayleigh instabilities. The addition of nanotubes did not improve web strength of the products compared to virgin polymer. Overall, centrifugal spinning has proven to be a highly versatile technique, capable of producing ultrafine fibres from a range of polymer feed materials which have potential to be utilised in a range of specialist applications.
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Lamb, Clare. "Stable carbon isotope variation during natural chloromethane and bromomethane production." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343035.
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Bogdanova, Maria Ivanova. "Variation in parental investment during avian egg production and incubation." Thesis, University of Glasgow, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418349.
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Ghahramani, Zachary. "Variation in sound production of the blue catfish, Ictalurus furcatus." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/139.
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The blue catfish, Ictalurus furcatus, is an invasive species introduced to Virginia in 1974 and is the largest catfish in the United States. Like other Ictalurids, they are capable of producing disturbance calls via stridulation of the pectoral spine. These sounds can be made in air and water, and catfish can be preyed upon by both aerial and underwater predators. I characterized these putative distress calls by recording them in air and in the fish’s natural habitat. Sounds exhibited a wide variation in acoustic parameters relative to fish ontogeny: larger fish produced higher amplitude sounds with lower frequency bands. Sweep and pulse duration increased with fish size, but pulse rate and the number of pulses per sweep decreased. Sounds were more robust in water with a 1400 fold increase in sound pressure compared to air. Frequency response was much more peaked underwater with a considerable amount of high frequency absorption. These sounds appear to be better adapted to water, suggesting that their use in air may be inconsequential.
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Bengtsson, Viktor, and Philip Skarheden. "Ökat kapacitetsutnyttjande genom reducerad processvariation :." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-53016.
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Studien är utförd på ett fallföretag med syftet att skapa en djupare förståelse för hur stabilisering av en produktionsprocess påverkar kapacitetsutnyttjandet. Nuläget analyserades genom observationer, intervjuer och företagets egen dokumentation. Två experiment utfördes vilket resulterade i att ett samband hittades mellan variationer och kapacitetsutnyttjandet i en produktionsprocess. Vidare avgränsades vilka produktionsförutsättningar som gav högst kapacitetsutnyttjande. Slutligen presenteras hur det ökade kapacitetsutnyttjandet påverkar de ekonomiska resultaten samt studiens slutsats och rekommendationer till fallföretaget.
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Häggblom, Victor, and Alexander Nilsson. "Reducera variation vid omställning genom standardiserat arbete." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-19537.
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Volvo Cars in Skövde aims to reduce their waste in their crankshaft-line where they produce two types of crankshafts, type 2, and type 7. The intention with this work is to schedule the total changeover of the production line to identify potential actions that could reduce the changeover time and its variation. In the current state 7 operators are being used to carry out the changeover. One of the tasks that were handed out from Volvo was to examine how many operators that are required to carry out the changeover without any loses from waiting for operators. A time-study has been done which provides a clear overview of how the changeover is done right now, observations of the production line and interviews of the operators were also made. From this data a map was created of how the changeover should be done in theory, both for the workflow and for the operators. The result of the methods showed that it is a big variation between the changeover-times, this is due to that there are no work instructions for the operators and thereby no standardized work procedure. From the mapping the number of operators that are needed to carry out a changeover has been calculated and determined. The sequence in which all elements are to be performed and how they are to be prioritized was also obtained from the theoretical changeover. This then formed the basis of which the instructions for the operators were created upon and became the standardized work that was implemented. The theoret-ical changeover also showed that it is possible to carry out the changeover with only two operators. The instructions were also tested in practice with a result that showed that it can be done and even reduce the changeover-time, but further work is required to verify the working method. To verify that the new way of working reduces the variation more measurements need to be done but with the in-structions the variation should be reduced. To further improve the changeover, a theoretical timeline was made of how the changeover would be made with three improvement proposals implemented. The results from them showed that if introduced, they would reduce the changeover time by 61%.Volvo Personvagnar i Skövde vill minska slöserierna i deras vevaxel-linje där de producerar två typer av vevaxlar, typ 2 och typ 7. Arbetets avsikt är att kartlägga produktionslinans omställning i nuläget för att kunna identifiera potentiella åtgärder som kan reducera omställningstiden och dess variation. I nuläget används 7 operatörer som är uppdelade på olika områden för att genomföra omställningen. Ett av uppdragen från Volvo var att undersöka hur många operatörer som krävs för att genomföra omställningen över hela linjen utan att förluster beroende på operatörsväntan. Tidsstudier har genomförts för att skapa en tydlig överblick av hur omställningen ser ut i nuläget, det utfördes även observationer av produktionslinan samt intervjuer med operatörer. Med hjälp av denna data gjordes en kartläggning av hur en omställning borde göras i teorin, både för flödet och för opera-törerna. Resultatet av metoderna visade att det är en stor variation mellan omställningstiderna och att detta till största del beror på att det inte finns några instruktioner för hur operatörerna ska genomföra en omställning och därmed inget standardiserat arbetssätt. Från kartläggningen kunde sedan antalet operatörer som behövs för att genomföra en omställning beräknas och fastställas. Sekvensen som alla moment ska genomföras i och hur de ska prioriteras erhölls också från den teoretiska omställningen. Detta utgjorde sedan grunden för de instruktioner som skapades för operatörerna och blev det standardiserade arbetssätt som infördes. Den teoretiska omställningen visade också att omställningen går att genomföra med endast två operatörer. Instruktionerna för två operatörer testades även i praktiken med ett resultat som visade att det är genomförbart och även kan reducera omställningstiden men det krävs vidare arbete för att verifiera arbetssättet. För att kunna verifiera att det nya arbetssättet reducerar variationen av omställningstiden hade fler mätningar behövts göras men med hjälp av instruktionerna borde variationen reduceras betydligt. För att förbättra omställningarna ytterligare gjordes även en teoretisk tidslinje över hur omställningen skulle genomföras med tre förbättringsförslag implementerade. Resultatet visade att en implementering av förbättringsförslagen kan leda till en reducering av omställningstiden med 61%.
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Uggla, Madeleine. "Domestication of wild roses for fruit production /." Alnarp : Dept. of Crop Science, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a480.pdf.
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Myers, Bonnie Jean Evaline. "Variations in Community Fish Production and Diversity Across the Appalachians: Implications for Climate Change." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25803.
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Climate change is considered a major threat to freshwater ecosystems through altering biodiversity, structure, and function. Having a thorough understanding of how diverse ecosystems respond to temperature change is vital to ecosystem management and conservation. During summer 2012, I quantified fish biomass, somatic growth, secondary production, and habitat data for fish communities in 25 Appalachian streams from Vermont to North Carolina. Multiple statistical tests were conducted to determine the relationship between community fish production and air and water temperature, species thermal guild production and air and water temperature, and the relationship between community fish production and diversity. Community fish production estimates ranged from 0.15 to 6.79 g m-2 yr-1 and community P/B ratios ranged from 0.21 to 1.07. No significant differences existed between mean community production estimates at the cold-water, cool-water, warm-water, and extreme northern sites (P=0.19), but P/B ratios in the extreme northern streams were statistically higher than mean community P/B in cold- and cool-water streams in the southern Appalachians (P=0.002). Water temperatures had a positive effect on community fish production (P=0.01) while air temperatures did not (P=0.10). Both air and water temperatures were significant in predicting whether community production would be dominated by cold-water or cool-water fish (P=0.001, P<0.0001, respectively). Community fish production was significantly, positively related to species richness (R2=0.38, P=0.001) and was one of the highest correlates of community production (R2=0.52). As climate change alters freshwater ecosystems, fish communities may transform by means of shifting fish abundance, biomass, and production among species ultimately affecting ecosystem structure, function, and biodiversity.Master of Science
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Bossavy, Arthur. "Caractérisation et prédiction probabiliste des variations brusques et importantes de la production éolienne." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00803234.
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L'énergie éolienne est aujourd'hui la source d'énergie renouvelable en plus forte expansion. Le caractère variable et partiellement contrôlable de sa production complexifie la gestion du système électrique. L'utilisation dans divers processus de décision, de prédictions du niveau de production à des horizons de 2-3 jours, permet une meilleure intégration de cette ressource. Certaines situations donnent néanmoins lieu à des performances de prédiction insatisfaisantes. Des erreurs dans la prédiction de l'instant d'apparition de variations brusques et importantes de la production, peuvent être responsables d'importants déséquilibres énergétiques, et avoir un impact négatif sur la gestion du système électrique. L'objectif de cette thèse est de proposer des approches permettant d'une part de caractériser ces variations, et d'autre part de prédire et d'estimer l'incertitude dans l'instant de leur apparition. Dans un premier temps, nous étudions différentes formes de caractérisation de ces variations. Nous proposons un modèle de rupture permettant de représenter le caractère aléatoire dans la proximité des ruptures d'un signal, tout en tenant compte des aspects borné et non-stationnaire du processus de production. A partir de simulations issues de ce modèle, nous réalisons une étude paramétrique destinée à évaluer et comparer les performances de différents filtres et approches multi-échelles de détection. Dans un deuxième temps, nous proposons une approche de prédiction probabiliste de l'instant d'apparition d'une rupture, reposant sur l'utilisation de prévisions météorologiques ensemblistes. Leur conversion en puissance fournit différents scénarii de la production, à partir desquels sont agrégées les prédictions de l'instant d'apparition d'une rupture. L'incertitude associée est représentée à l'aide d'intervalles de confiance temporels et de probabilités estimées conditionnellement. Nous évaluons la fiabilité et la finesse de ces estimations sur la base de mesures de production provenant de différentes fermes éoliennes.
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Bouayed, Salim. "Variations de la production nasal de monoxyde d'azote (NO) dans la rhinosinusite chronique /." Genève : [s.n.], 2007. http://www.unige.ch/cyberdocuments/theses2007/BouayedS/these.pdf.
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Snoeren, Natalie Dominique. "Variations phonologiques en production et perception de la parole : le phénomène de l'assimilation." Paris 5, 2005. http://www.theses.fr/2005PA05H035.
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Cette thèse porte sur la variation phonologique de l'assimilation de voisement en français. La première série d'expériences a eu pour objectif d'étudier la production des mots assimilés. Nous avons proposé un nouvel indice acoustique pour mesurer le degré d'assimilation entre deux mots. Les mesures acoustiques ont montré que l'assimilation est souvent un processus gradué plutôt que dichotomique et modulé par le voisement sous-jacent. Les résultats de la deuxième série d'expériences d'amorçage intermodal ont montré que le rôle du contexte droit varie en fonction du degré d'assimilation. Le traitement perceptif des mots complètement assimilés est facilité en présence du contexte droit, alors que la présences des traces acoustiques dans les mots assimilés était confirmée dans une troisième série d'expériences en amorçage sémantiqueThe present PhD thesis provides an in-depth study of a phonological variation frequently encountered in French, namely voice assimilation. The goal of the first series of experiments was to study the production of assimilated words and to provide an acoustico-phonetic description of word-final assimilated obstruents. Acoustic measurements showed that voice assimilation is often a graded, rather than a categorical phonetic process. Moreover, degrees of assimilation varied as a function of underlying voicing. Cross-modal priming results showed that the role of phonological right context varies as a function of the degree of assimilation. Perceptual processing of completely assimilated segments was facilitated in the presence of the right context, whereas the presence of "acoustic traces" sufficed to access partially assimilated segments. The hypothesis of the presence of acoustic traces in assimilated words was confirmed in the third series of experiments using semantic priming
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Ross, Michael C. M. B. A. Sloan School of Management. "Reducing variations in a highly constrained environment in order to increase production capacity." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/126988.
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Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, in conjunction with the Leaders for Global Operations Program at MIT, May, 2020Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, in conjunction with the Leaders for Global Operations Program at MIT, May, 2020
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 89-90).
Variations and the negatives effects it causes on production capacity and planning are topics of significant interest in the manufacturing communities. This research investigates the hypothesis that, when operating in a highly constrained environment, capacity can be gained by reducing the variations within the system. This study tests this hypothesis through simulation, data analysis, and controlled testing on the variations responsible for limiting capacity at Vektek LLC. The variability in lead times, quality, batch ordering, and demand forecasting contributes to the Bullwhip Effect. This increase in variability will cause excessive inventory, overtime costs, unacceptable service levels, high production costs, and large lead times. This research reduces these variabilities by isolating each cause of variability and placing standard work around it, such as SOPs. Once isolated and controlled, variations were methodically reduced, and significant capacity was gained. The research results show us that the overall variations were reduced by 26.5%. Due to this: overtime costs were reduced, late shipments were reduced by 40.0%, WIP inventories were reduced by 38.0%, and lead times were reduced roughly 22%. The total monetary value saved is estimated to be $988k and the total capacity gained was 30.8%. These results provide an initial validation that reducing the variations will increase the capacity.
by Michael C. Ross.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Weston, Richard. "Investigation into spatial variations in the production of market sector housing in England." Thesis, Nottingham Trent University, 2007. http://irep.ntu.ac.uk/id/eprint/289/.
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Over recent decades the UK has seen an increasing shift in housing tenure away from privately or socially rented towards home ownership. Whilst the number of properties constructed for rent has fallen, particularly in the social sector, this has not been matched by rises in private sector construction for owner occupation. With the population continuing to grow and a reduction in average household size there is an increasing gap between need and provision. This shortage has exacerbated house price inflation, making it increasingly difficult for first-time buyers to enter the market and causing further disparity in wealth distribution. This thesis investigates spatial variations in market sector production between 1995 and 2002. In particular it will focus on the supply of new housing for owner occupation, as this is the dominant housing tenure in England. The aim of the research is to provide an economics-based explanation to spatial variations in production but with a 'holistic' approach to the investigation of house building. The research develops an approach to investigating house building that involves the triangulation of theory with qualitative and quantitative methods. In particular the research seeks to challenge the popular preconception that markets are ?naturally? efficient and that any form of regulation will automatically reduce this efficiency. This thesis presents a novel model of residential developer behaviour, which improves the understanding of the decision-making process, focussing in particular on the consequences of uncertainty. Secondly, it identifies the set of factors that influence the levels of housing production in the market sector for the study period, delineating a causal chain that demonstrates cause and effect. In particular it questions the accepted notion that planning regulation is the primary cause of falling output and that an increase in land released through planning will both increase output and reduce house prices.
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Pirzada, Rashid Hussain. "Genetic analysis of production, fertility and health traits of dairy cows." Thesis, Bangor University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364588.
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Hart, Adam Michael. "Seasonal Variation in Whole Stream Metabolism across Varying Land Use Types." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23256.
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Historically, whole stream open channel metabolism has been measured over short periods in conjunction with nutrient injections to assess nutrient dynamics within streams. The purpose of my study was to understand the seasonal changes in metabolism within and among streams as well as the impacts of different land use. This was addressed by monitoring nine different watersheds in the Little Tennessee River watershed in southwestern North Carolina. The nine study watersheds were selected to represent a gradient of forested, agricultural, and developed land use / land cover types. Data loggers were deployed to collect continuous oxygen, temperature, conductivity, and stage height data from 2010-2011. I used these data to estimate gross primary production (GPP) and ecosystem respiration (ER). GPP and ER were compared to stream chemistry, light, land cover, and storms. I found that there is greater influence of local riparian land cover than watershed land cover on GPP and ER. Streams had varying annual GPP, but generally the peak in GPP occurred in late winter- early spring with lows in fall. GPP was most strongly influenced by the amount of available light, which is directly related to the amount of canopy cover. ER was much more variable than GPP within and among streams but generally peaked in summer and was lowest in the winter. ER was most strongly related to the proportion of agricultural land cover in the local riparian area. My results suggest that local riparian vegetation may have a greater impact on metabolism than mountainside development.Master of Science
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Salawu, Lukman. "Large-scale nutrient pattern in the Gulf of Bothnia with the hydrodynamic of its loads." Thesis, Linköping University, The Tema Institute, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6797.
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Eutrophication, which is the most important degradation in water bodies, has been traced to the imposed loading of nutrients. Of interest is the fact that the process is often accompanied with undesirable effects, one of which is primarily the increased algae production at the surface and accumulation of biomass at the bottom and the secondary responses, which include a., change in species composition b. change in the biogeochemical cycle c. shift in the seasonal pattern and magnitude variability.
The biogeochemical cycle in response to hydrodynamic alterations may occur internally; however external loading often fosters the process over large spatial scales. In the quest of validating the above statement, we hypothesized that there is no difference in the mean concentration of nutrients in the Gulf of Bothnia from the overall mean concentration.
The analysis was done with a probability mapping method, in which all stations were grouped into a lattice. The cells are constructed using a grid system, i.e. x and y axis (longitude and latitude). Basically the method statistically tested for variables deviating from the over mean concentration. The variables analyzed are DIN, DSi, DIP and DIN: DSi.
Results of the analysis showed significant spatial variations in the nutrient distribution in the Gulf of Bothnia; such differences were observed in the coastal to the deep zones of the Gulf.
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Busà, Veronica. "La production de /R/ chez les locuteurs de Niamey : une première enquête de terrain." Thesis, Paris 10, 2018. http://www.theses.fr/2018PA100008/document.
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Notre étude s’intéresse à un aspect phonologique : le comportement du phonème /R/ du français parlé à Niamey, capitale du Niger, pays de l’Afrique subsaharienne. L’enquête a été mené selon le protocole du projet international, Phonologie du Français Contemporain (abrégé PFC). Il vise à rassembler un vaste corpus oral de français contemporain à travers toutes les zones francophones du monde.Nos enquêtes de terrain ont été effectuées dans une ville où le français demeure la langue officielle, et où l’on retrouve aussi d’autres langues nationales et/ou locales (haousa, songhaï-zarma, touareg, peul, kanuri et arabes). Une présentation des rhotiques du point de vue phonétique et phonologique s’est avéré nécessaire, avant la classification et l’analyse de nos données. D’une part nous avons analysé les allophones de /R/ réalisés par les enquêtés. Ces analyses montrent que la réalisation largement majoritaire est la vibrante alvéolaire [r], suivie de loin par la fricative uvulaire [ʁ], puis par les réalisations [ɰ], [χ], [ɻ] et la non-réalisation de /R/ [ø]. Tous ces résultats ont été comparés ensuite à ceux d’autres points d’enquêtes PFC dans le monde. D’autre part, nous nous sommes intéressés à la chute de /R/ dans les groupes consonantiques et en finales, pour aboutir à la conclusion que ce phénomène dépend du lexique et, plus exactement, concerne généralement la prononciation des chiffres (par exemple quatre [katR]> [kat])This thesis focuses on the phonological aspect of the /R/ in French language spoken in Niamey, the capital of Niger, a Sub-Saharan country of Africa. The survey has been conducted conforms to theprotocol and the mehology of an international project Phonologie du Français Contemporain (PFC), which aims to collect a large corpus of contemporary French spoken from all around the word. In Niamey, French coexists with others national and local languages: haousa, songhaï-zarma, touareg, peul, kanuri et arabic.In the proposed work at first we have illustrated a phonetic and phonology classification of rhotics class, then we have classified and analyzed our data. We have analyzed all allophones of /R/ produced by the interviewed speakers. These data show that the largest part of the speaker pronounce a vibrant alveolar [r], followed by a fricative uvular [ʁ], and then by [ɰ], [χ], [ɻ] and [ø]. Furthermore, we have compared our results with other PFC studies conducted all around the francophone word. Additionally, we have focused on fall of /R/ in cluster group, and we concluded that this fall depends on the lexicon, and concerns especially numbers pronunciation (for example, quatre [katR]> [kat])
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Cheung, Wing-ki Jovy. "Variation in the production of alveolar fricative /s/ in Hong Kong Cantonese." Click to view the E-thesis via HKU Scholors Hub, 2005. http://lookup.lib.hku.hk/lookup/bib/B38279083.
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Thesis (B.Sc)--University of Hong Kong, 2005."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2005." Also available in print.
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McBeth, Lucien Reiter. "EFFECTS OF TRANSIENT VARIATION OF SILAGE DRY MATTER CONCENTRATION ON LACTATING DAIRY COWS." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345489864.
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Bli, Bi Trazié Serge. "Francophonie et diversité : autour des constructions verbales en Côte d’Ivoire à travers l’exemple de productions écrites et orales d’étudiants de l’Université Félix Houphouët-Boigny d’Abidjan." Thesis, Paris 10, 2014. http://www.theses.fr/2014PA100121.
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Ces travaux approchent la question de la diversité dans la Francophonie sur la base de constructions verbales en Côte d’Ivoire. L’étude du sous-corpus écrit montre ainsi que le fait que 232 sur 400 étudiants soient concernés par des « écarts » de constructions verbales relève essentiellement d’une « connaissance approximative de la valence du verbe employé ». Quant à l’interférence du français ivoirien ordinaire, elle diminue progressivement jusqu’à la Licence (Licence 3) avant de présenter une chute significative en Maîtrise (Master 1). L’analyse du sous-corpus oral souligne ensuite des constructions verbales typiques du français ivoirien ordinaire. Nous en déduisons que les étudiants des années supérieures manient mieux le français standard, et la variation en général, que ceux des premières années. Nous proposons dès lors une didactique du français de Côte d’Ivoire jetant les bases pédagogiques de la variation du français en Côte d’Ivoire tout en insistant sur l’intérêt d’une norme grammaticale pour l’ensemble du monde francophoneThese studies approach the issue of diversity in the Francophonie on the basis of verbal constructions in Côte d'Ivoire. The study of written sub-corpus shows that the fact that 232 out of 400 students are involved with "gaps" in verbal constructions is essentially an "approximate knowledge of the valence of the verb used." As for the interference of the standard ivorian french, it gradually decreases to the License (Licence 3) before presenting a significant drop in Master (Master 1). The analysis of oral sub-corpus then highlights typical verbal constructions of standard ivorian french. We conclude that students in senior years handle better the standard french and the change in general, than those of early years. We therefore propose a didactics of french in Côte d’Ivoire laying the educational foundation of the change in french in Côte d’Ivoire while emphasizing the importance of a grammatical standard for the entire french-speaking world
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Tracol, Yann. "Etude des variations interannuelles de la production herbacée des pâturages sahéliens : exemple du Gourma malien." Toulouse 3, 2004. http://www.theses.fr/2004TOU30032.
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Fortement dépendante de la disponibilité en eau du sol, et donc du régime de la mousson ouest africaine, la dynamique saisonnière et interannuelle de la végétation herbacée sahélienne montre une forte variabilité spatiale et temporelle de la production végétale. L'objectif principal de cette thèse est d'analyser et de caractériser le fonctionnement du tapis herbacé à l'aide de la modélisation et de mesures de terrain pour expliquer les variations de la production primaire en relation avec les forçages externes principalement de nature climatique mais aussi biotique comme l'activité pastorale. L'analyse de mesures récoltées durant la période 1984-2002 dans une région du Sahel, le Gourma malien, démontre une réponse complexe du tapis herbacé face aux contraintes environnementales en terme de production mais aussi de recouvrement et diversité. Par ailleurs, les mesures sur l'ensemble du Gourma contribuent à décrire un gradient nord-sud de la végétation en relation avec la variabilité spatiale des précipitations en terme de cumul et de distribution. Le modèle de fonctionnement STEP (Sahelian Transpiration Evaporation and Production model) adapté aux zones arides simule à l'échelle de la station, le bilan hydrique et l'évolution journalière de la masse herbacée épigée. Le fonctionnement de la végétation herbacée est alors quantifié à l'aide des efficiences d'utilisation de la lumière et de l'eau dérivées des simulations. .Strongly constrained by the soil water content and consequently by the West African Monsoon, the herbaceous layer shows a large space-time variability. The main goal of this thesis is to analyse and characterise the Sahelian grassland functioning thanks to models and field measurements to explain the primary net production variability in relation with a large number of forcing climatic and biotic variables like pasture pressure. The analysis of data recorded between 1984 and 2002 in a Sahel zone, the Malian Gourma shows us a complex response of the herbaceous strata in terms of production, fraction cover and diversity. Moreover, the field measurements available for the Gourma permit to describe a north-south gradient of vegetation according to the spatial variability of annual rainfall. .
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Portig, Alex A. "Strangford Lough, overwintering birds, and variation in eelgrass (Zostera spp) production and distribution." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361228.
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Bradfield, M. F. A. (Michael Ford Alexander). "Continuous production of succinic acid by Actinobacillus succinogenes : steady state metabolic flux variation." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/40826.
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Continuous fermentations were performed in a novel external-recycle, biofilm reactor using D-glucose and CO2 as carbon substrates. Corn steep liquor (CSL) and yeast extract (YE) served as nitrogen sources.
In anaerobic fermentations using medium containing CSL and YE, succinic acid (SA) yields were found to be an increasing function of glucose consumption. The ratio of SA to the major by-product, acetic acid (YAASA), increased from 2.4 g g-1 at a glucose consumption of 15 g L-1, to 5.7 g g-1 at a glucose consumption of 46 g L-1. For medium containing no CSL, YAASA remained near 1.97 g g-1, exceeding this for cases where biofilm grown on CSL-containing medium was present.
The ratio of formic acid to acetic acid (YAAFA), for CSL-containing medium, decreased from an equimolar value (0.77 g g-1) at a glucose consumption of 10 g L-1 to zero at 46 g L-1 glucose consumed. In contrast, YAAFA for YE-only medium remained at 0.77 g g-1. Therefore, pyruvate was metabolised solely by pyruvate-formate lyase when no CSL was present.
The highest SA yield obtained on glucose, SA titre and SA productivity were 0.91 g g-1, 48.5 g L-1 and 9.4 g L-1 h-1, respectively, all for medium containing CSL. Medium that included CSL significantly outperformed medium that excluded CSL, achieving 64%, 21% and 203% greater SA titres, yields on glucose and productivities respectively.
Metabolic flux analyses based on the established C3 and C4 metabolic pathways of Actinobacillus succinogenes revealed that the increase in YAASA, for CSL-containing fermentations, could not be attributed to the decrease in formate and biomass formation, and that an additional source of reducing power was present. The fraction of reducing power (NADH) unaccounted for increased with glucose consumption, suggesting that the maintenance or non-growth metabolism encountered at higher SA titres differs from the growth metabolism. It is postulated that the additional reducing power originates from an active pentose phosphate pathway in non-growing cells or from an undetected component(s) in the fermentation medium. No major metabolic flux variations were found in fermentations that excluded CSL.Dissertation (MEng)--University of Pretoria, 2013.
gm2014
Chemical Engineering
unrestricted
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Hutton, Brittany A. "Variation in Sound Production by the Pot-bellied Seahorse, Hippocampus Abdominalis, during Feeding." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504794445264358.
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Rivière, Philippe. "Performances saisonnières des groupes de production d'eau glacée." Paris, ENMP, 2004. http://www.theses.fr/2004ENMP1224.
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Hansson, Johanna. "The Swedish District Heating Market : Firm Ownership and Variations in Price, Costs of Production and Profitability." Thesis, Uppsala University, Department of Economics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-117589.
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The purpose of this investigation is to further the current discussion of how the Swedish market for district heating can be made more competitive and effective. This is done by investigating how price, costs of production and profitability of district heating varies with ownership, a variable frequently held accountable for financial performance variations in natural monopoly markets. The investigation is based on financial and technical performance data from 203 firms from 2007 and 2008, compiled by the Swedish Energy Market Inspectorate. The results strongly indicate that private firms are more profitable than firms owned, fully or partly, by local government. Furthermore, the results find that higher profitability tends to be positively correlated with prices, rather than negatively with costs of production. The results speak in favor of private ownership under regulation, rather than the current mixture of public and unregulated private ownership.
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Merzouk, Anissa. "Contrôle des variations à court terme de la production biologique de diméthylsulfure (DMS) en milieu marin." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24205/24205.pdf.
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Le diméthylsulfure (DMS) est un gaz qui exerce un effet refroidissant sur le climat en contribuant à la formation de nuages, ce qui diminue la quantité de radiations solaires pénétrant dans l’atmosphère. Le DMS est produit dans les océans par la dégradation du diméthylsulfoniopropionate (DMSP) synthétisé par certaines espèces de phytoplancton. Plusieurs de ces espèces algales peuvent convertir directement le DMSP en DMS, mais dans la plupart des cas, le DMS est produit par voie indirecte, via la libération du DMSP algal, puis sa conversion en DMS par les bactéries marines. La production de DMS constitue moins de 10% du DMSP dégradé par les bactéries, qui l’utilisent principalement comme source de soufre. Les variations à court terme de la production biologique de DMS et des facteurs environnementaux qui la régulent ont été étudiés dans l’estuaire du Saint-Laurent, le Pacifique nord-est et l’Atlantique nord-ouest. Dans l’estuaire du Saint-Laurent, les concentrations de DMSP et de DMS en surface variaient fortement pendant la journée avec des maxima vers midi et des minima la nuit. Ces variations journalières s’expliquaient par la présence de dinoflagellés riches en DMSP qui effectuaient des migrations verticales diurnes associé à une production accrue de DMSP et de DMS en réponse aux fortes radiations solaires pendant la journée. Dans le Pacifique NE, les faibles concentrations de fer favorisaient une communauté algale riche en DMSP. L’ajout de fer dans cet écosystème a induit un appauvrissement en DMS par rapport aux eaux environnantes dû à un changement de la communauté phytoplanctonique en faveur de diatomées pauvres en DMSP, accompagné d’une augmentation de l’activité et du nombre des bactéries. Les bactéries en croissance ont alors modifié leur utilisation du DMSP et produisaient très peu de DMS. Dans l’Atlantique NO, le déclin de la floraison printanière des diatomées a été marqué par une diminution importante des concentrations de DMSP en surface. La consommation de DMSP et la production de DMS par les bactéries ont aussi rapidement diminué probablement parce que les bactéries ont satisfait leurs besoins énergétiques grâce à d’autres substrats organiques plus disponibles que le DMSP. Les concentrations et les taux de transformation biologique du cycle du DMS(P) varient rapidement et de façon importante à l’échelle des heures et des jours. L’étude de ces variations à court terme est essentielle si l’on veut adéquatement quantifier la production de DMS en milieu marin et son effet sur le climat.Dimethylsulfide (DMS) is a biogenic gas exerting a cooling effect on climate by promoting cloud formation, thus decreasing the amount of solar radiation entering the atmosphere. DMS is produced in the oceans from the degradation of dimethylsulfoniopropionate (DMSP) synthesized by marine phytoplankton. Some algal DMSP-producers have the capability to directly produce DMS, but a large part of the production of DMS is believed to occur indirectly, through the release of algal DMSP and its uptake and utilization by bacteria. DMS production represents less than 10% of the DMSP degraded by bacteria, which utilize it mainly as a source of sulfur. Short-term variations of the biological DMS production and its controlling factors were studied in the St. Lawrence Estuary, the northeast Pacific and the northwest Atlantic. In the St. Lawrence Estuary, DMSP and DMS concentrations exhibited large and rapid variations with maxima around noon and minima during the night. These variations were largely explained by the diurnal vertical migration of DMSP-rich dinoflagellates associated with an increased DMSP and DMS production under high solar irradiance during the day. In the NE Pacific, the low prevailing iron concentrations favoured a DMSP-rich algal community. The iron enrichment induced a decrease in DMS relative to non-enriched waters due to a change in the phytoplankton community toward DMSP-poor diatoms and an increase in the abundance and activity of bacteria. This growing bacterial community modified its DMSP utilization and produced little DMS. In the NO Atlantic, the decline of the diatom spring bloom was characterized by a decrease in DMSP concentrations in surface waters. DMSP consumption and DMS production by bacteria also rapidly decreased, probably because they satisfied their metabolic requirements with other organic substrates more readily available than DMSP. The pools and biological processes of the DMS(P) cycle vary at scales of hours and days. The study of these short-term variations is needed to accurately measure DMS production and to better assess its effect on climate.
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AIT, ICHOU MOHAMED. "Diversite genomique, variations phenotypiques et production des enzymes extracellulaires chez pseudomonas aeruginosa implique dans la mucoviscidose." Tours, 1996. http://www.theses.fr/1996TOUR3304.
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Sörensen, Tony, and Niclas Freijd. "A MODEL FOR HOW TO DECREASE VARIATION IN A PRODUCTION PROCESS - A CASE STUDY." Thesis, Linnéuniversitetet, Institutionen för teknik, TEK, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-20335.
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The purpose of this bachelor thesis is to develop a generic model to be applied on to a Swedish company. In order to reduce variations in quality, production time and work routines. The study starts by investigation of the relevance of this thesis and continues with providing relevant theories on the subject. Then a model was developed for continues improvement projects with different keys that can be applied in the different steps of the model. The keys show the importance of involving the employees in continuous improvements projects. The model is aimed to be applicable to different kinds of project and depending of the size of the project, different keys can be utilized. The purpose of the model in this thesis is to decrease variation in quality, production time and work routines at a case company. The case company in this study is International Färg AB who is a manufacture of protective coatings. During the testing phase of the model, planning, analysis and measurements has been performed in order to achieve suggestions that would lower the variation within the production at the case company. The result of this thesis and the model is that with the use of the model developed in this thesis it is possible to achieve lower variations in the production. The thesis is aimed to be suitable to Swedish industrial companies. The authors provide a generic user-friendly model. From the results recommendations to the case company has been developed. The thesis end with a discussion about topics not fully covered in the report.
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Fowler, Bryan Keith. "Primary Production and Temporal Variation in the Macrophytic Community of a Tidal Freshwater Swamp." W&M ScholarWorks, 1987. https://scholarworks.wm.edu/etd/1539617574.
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Freret, Sandrine. "Variation des apports alimentaires, statut métabolique et production d'embryons chez la vache laitière superovulée." Paris, AgroParisTech, 2007. http://www.theses.fr/2007AGPT0027.
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Andy, Saryoko. "Genotypic Variation in Yield Performance under Tropical Environments of Soybeans with Temperate and Tropical Origins." Kyoto University, 2018. http://hdl.handle.net/2433/232342.
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Monjoly, Stéphanie. "Outils de prédiction pour la production d’électricité d’origine éolienne : application à l’optimisation du couplage aux réseaux de distributions d’électricité." Thesis, Antilles-Guyane, 2013. http://www.theses.fr/2013AGUY0679/document.
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La forte variabilité de la vitesse du vent fait que l'énergie produite par un parc éolien n'est pas constante dans le temps. Le gestionnaire ne peut donc pas dimensionner son réseau électrique en prenant intégralement ce type de production en compte. L' une des solutions préconisées pour permettre le développement de l' éolien et son intégration avec une plus grande sureté aux réseaux, est de développer et d'améliorer les outils de prévisions. Le travail de thèse consiste à améliorer les performances d'un outil de prédiction basé sur les réseaux de neurones bayesiens, permettant la prédiction de la puissance à très court terme . Le prédicteur fonctionne notamment par J'ajustement de paramètres, certain se détermine « automatiquement » via le mécanisme des réseaux de neurones bayesiens d' autres, que nous nommerons paramètres temporels, sont à l' appréciation de l'utilisateur. Le travail mené consiste à établir un protocole pour la fixation de ces paramètres tout en améliorant les performances du prédicteur . Nous avons donc décidé de conditionner leurs valeurs en fonction de la variabilité des séquences de puissance précédent l'instant de prévision. Tout d'abord nous avons classifié des séquences de puissance en fonction de leurs coefficients de variation en appliquant la méthode des C-moyennes floues. Puis, chaque classe formée a été testée sur plusieurs valeurs de paramètres, les valeurs associées aux meilleures prédictions ont été retenues. Enfin, ces résultats couplés au formalisme des Chaines de Markov, par le biais de la matrice de transition , ont perm is d'obtenir des taux d'amélioration par rapport à la persistance allant de 7,73 à 23,22 % selon l'horizon de prédiction considéréThe high variability of the wind speed has for conse quences that the energy produced by a wind farm is not constant over time. Therefore, the manager can't size the electrical network by takin g into account this type of production. One solution advocated for the development of wind energy and its integrati on with greater security at network, is to develop and improve fore casting tools. The thesi s objective is to improve the performance of a predi ction tool based on Bayesian neural networks, allowing the predi ction of wind power for short timescales. The predictor works, in part icular by the adjustment of parameters, sorne is determined "automatically" through the mechan ism of neural networks Bayesian other , which we cali temporal parameters are at the discretion of the user. The work involves establishing a protocol for the determination of these parameters and improving the performance of the predictor. So, we decided to condition their values depending on the sequence variability of wind power previous the moment of the forecast. First we classified sequences of power according to their coefficients of variation using the method of fuzzy C-means. Then, each formed class was tested for several parameters values, the values associated with the best predictions were selected. Finally , these result s coupled with the formalism of Markov chains , through the transition matrix allowed to obtain rates of improvement over the persistence ranging from 7.73 to 23.22 % depending on the prediction horizon considered
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Blacklock, Oliver S. "Characteristics of variation in production of normal and disordered fricatives using reduced-variance spectral methods." Thesis, University of Southampton, 2004. https://eprints.soton.ac.uk/420069/.
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Le, Roux Yves. "Qualité protéique des laits à la production : facteurs de variation et recherche d'indicateurs de protéolyse." Vandoeuvre-les-Nancy, INPL, 1994. http://docnum.univ-lorraine.fr/public/INPL_T_1994_LE_ROUX_Y.pdf.
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Une meilleure connaissance des réelles incidences des types de protéolyse dans le lait, associée à la recherche d'indicateurs pourrait permettre de diminuer le risque de dégradation des protéines et d'effectuer un tri du lait pour les fabrications sensibles. Les objectifs du travail sont : mesurer l'incidence de la protéolyse microbienne en fonction de différents niveaux de contamination, étudier les facteurs de variation de la protéolyse endogène, étudier les interactions entre ces deux types de protéolyse, caractériser un ou des indicateurs de protéolyse, témoins de la dégradation des protéines du lait. Des contaminations de 10⁶ germes/ml n'induisent pas de baisses des rendements fromagers ni des défauts de gout en transformation de type pate molle. La protéolyse microbienne, mesurée par une diminution du pourcentage en kappa-caséines, n'est significative que pour des contaminations supérieures à 10⁷ germes/ml, niveau obtenu après 144 heures de stockage à 4°C. Le stockage du lait au froid pendant plusieurs jours induit des phénomènes protéolytiques endogènes d'autant plus intenses que le dénombrement cellulaire initial est important. La protéolyse endogène, mesurée par augmentation du pourcentage des gamma-caséines ou de la teneur en protéose peptones, est significative pour des laits de quartier à faibles dénombrements cellulaires (<250 000 cellules/ml). Aucune interaction entre protéolyse endogène et microbienne n'a été observée. Le dénombrement cellulaire n'est pas un indicateur précis de l'intensité de la protéolyse dans les laits de quartier ou individuels, par contre, les variations de cette protéolyse peuvent être expliqués par la mesure combinée de la teneur en chlorures, du pH et du nombre de cellule (r2=0,77). La teneur en proteose peptone, contrairement à la mesure de la teneur en acides alpha-amines libres par l'acide 2, 4, 6 trinitrobenzène sulfonique, est une mesure sensible de la protéolyse microbienne et endogène. Le composant beta-caséine-1P (f29-105/107) de la fraction proteose peptones s'avère un très bon indicateur de la protéolyse endogène dans les laits de quartier
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Kifle, Demeke. "Seasonal and spatial variations in species composition, abundance, biomass and primary production of phytoplankton in Southampton Water, U.K." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334609.
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Eagle, Bryan Gary. "An evaluation of the relationship of automobile door distortions to variations in material properties and production operating parameters." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/29077.
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Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1994, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science & Engineering, 1994.Includes bibliographical references (p. 177-180).
by Bryan Gary Eagle.
M.S.