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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Small area market demand prediction in the automobile industry

Lu, Hongwei, Marketing, Australian School of Business, UNSW January 2008 (has links)
The general aim of this research is to investigate approaches to: •improve small area market demand (i.e. SAMD) prediction accuracy for the purchase of automobiles at the level of each Census Collection District (i.e. CCD); and •enhance understanding of meso-level marketing phenomena (i.e. geographically aggregated phenomena) relating to SAMD. Given the importance of SAMD prediction, and the limitations posed by current methods, four research questions are addressed: •What are the key challenges in meso-level SAMD prediction? •What variables affect SAMD prediction? •What techniques can be used to improve SAMD prediction? •What is the value of integrating these techniques to improve SAMD prediction? To answer these questions, possible solutions from two broad areas are examined: spatial analysis and data mining. The research is divided into two main studies. In the first study, a seven-step modelling process is developed for SAMD prediction. Several sets of models are analysed to examine the modelling techniques’ effectiveness in improving the accuracy of SAMD prediction. The second study involves two cases to: 1) explore the integration of these techniques and their advantages in SAMD prediction; and 2) gain insights into spatial marketing issues. The case study of Peugeot in the Sydney metropolitan area shows that urbanisation and geo-marketing factors can have a more important role in SAMD prediction than socio-demographic factors. Furthermore, results show that modelling spatial effects is the most important aspect of this prediction exercise. The value of the integration of techniques is in compensating for the weaknesses of conventional techniques, and in providing complementary and supplementary information for meso-level marketing analyses. Substantively, significant spatial variation and continuous patterns are found with the influence of key studied variables. The substantive implications of these findings have a bearing on both academic and managerial understanding. Also, the innovative methods (e.g. the SAMD modelling process and the model cube based technique comparison) developed from this research make significant contributions to marketing research methodology.
92

Análise estrutural de mangotes de transferência utilizando materiais compósitos e poliméricos avançados

Tonatto, Maikson Luiz Passaia January 2017 (has links)
Mangotes de transferência têm sido utilizados em grande quantidade em operações de descarga de óleo, principalmente em águas profundas, onde existem cargas estáticas e cíclicas variáveis devido ao ambiente de trabalho. Apesar da grande demanda dessas estruturas, seu comportamento é pouco conhecido e discutido na literatura devido a sua complexidade. Além disso, os materiais utilizados nesse equipamento podem ocasionar um elevado número de falhas, sendo muitas vezes superestimados, deixando o mangote com peso excessivo. Este trabalho objetiva o desenvolvimento de uma metodologia de análise de materiais poliméricos avançados, especificamente fibras de poliaramida e materiais compósitos à base de fibra de carbono, em substituição a materiais tradicionais, utilizando modelos numéricos capazes de prever o comportamento da pressão de ruptura das carcaças e resistência a compressão radial do mangote, além da avaliação em fadiga dos cordonéis à base de poliaramida dessas novas estruturas. Modelos em meso-escala foram desenvolvidos utilizando conceitos de hiperelasticidade e de critérios de falha de materiais compósitos para previsão das tensões e deformações locais em regiões críticas do mangote. Análises numéricas foram realizadas via elementos finitos com o software comercial para auxiliar a elaboração dos modelos e a realização dos cálculos numéricos. Foram realizados ensaios experimentais para validação desses modelos numéricos, bem como para a previsão do comportamento estático e em fadiga dos materiais envolvidos. Foram desenvolvidos dois modelos. Em um modelo foi aplicado pressão interna no mangote para previsão de ruptura das carcaças no qual tem o objetivo de avaliar o desempenho dos novos reforços de poliaramida. No outro modelo foi aplicada uma carga radial na seção central do mangote para prever a resistência ao esmagamento, no qual tem o objetivo de avaliar o desempenho do componente de sustentação em material compósito de fibra de carbono. Os resultados dos modelos numéricos apresentaram boa concordância com os resultados experimentais em grande parte das análises. Também se observou que os novos materiais apresentam um grande potencial de substituição dos materiais tradicionais, bem como um excelente comportamento frente a carregamentos estáticos e dinâmicos envolvidos na aplicação, sendo verificada diminuição significativa de peso e aumento do desempenho. / Offloading hoses have been extensively used at offloading oil operations, especially in deep water, where there are variable static and cyclic loads due to the working environment. Despite the great demand for these structures, their behavior is little known and discussed in the literature due to the complexity. In addition, the materials used in this equipment may lead to a high number of failures, being often overestimated, leading to excessive weight. This work aims to develop a methodology for analysis of advanced polymeric materials, specifically polyaramide fibers and carbon fiber composite materials, in the substitution of traditional materials, using numerical models able to predict the static behavior of the burst pressure of the carcasses and radial compression strength of the hose. In addition, fatigue tests were performed to evaluate the polyaramide cords of these new structures. Meso-scale models were developed using advanced hyperplastic and composite failure criteria concepts to predict local stresses and strains in critical regions of the hose. Numerical analyses were performed using finite elements with commercial software to aid the development of models and to carry out numerical calculations. Several experimental tests were performed to validate numerical models, as well as to forecast the static and fatigue behavior of the materials used. Two models were developed. A model is used to predict the burst pressure of the hose in order to evaluate the performance of the new polyaramide reinforcements cords. In the other model, a radial load was applied in the central section of the hose to predict the crushing strength, in which it has the aim of evaluating the performance of the load-bearing component made with carbon fiber composite material. The results of the computer models showed good agreement with the experimental results in most analyses. It was also found that the studied materials offered considerable potential for the substitution of traditional materials, as well as an excellent behavior under static and dynamic loads related to this application, with a significant weight reduction and increased performance of the new configurations over traditional hoses.
93

Consumption & class in evolutionary macroeconomics

Rengs, Bernhard, Scholz-Wäckerle, Manuel January 2018 (has links) (PDF)
This article contributes to the field of evolutionary macroeconomics by highlighting the dynamic interlinkages between micro-meso-macro with a Veblenian meso foundation in an agent-based macroeconomic model. Consumption is dependent on endogenously changing social class and signaling, such as bandwagon, Veblen and snob effects. In particular, we test the macroeconomic effects of this meso foundation in a generic agent-based model of a closed artificial economy. The model is stock-flow consistent and builds upon local decision heuristics of heterogeneous agents characterized by bounded rationality and satisficing behavior. These agents include a multitude of households (workers and capitalists), firms, banks as well as a capital goods firm, a government and a central bank. Simulation experiments indicate coevolutionary dynamics between signaling-by-consuming and firm specialization that eventually effect employment and consumer prices, as well as other macroeconomic aggregates.
94

Análise estrutural de mangotes de transferência utilizando materiais compósitos e poliméricos avançados

Tonatto, Maikson Luiz Passaia January 2017 (has links)
Mangotes de transferência têm sido utilizados em grande quantidade em operações de descarga de óleo, principalmente em águas profundas, onde existem cargas estáticas e cíclicas variáveis devido ao ambiente de trabalho. Apesar da grande demanda dessas estruturas, seu comportamento é pouco conhecido e discutido na literatura devido a sua complexidade. Além disso, os materiais utilizados nesse equipamento podem ocasionar um elevado número de falhas, sendo muitas vezes superestimados, deixando o mangote com peso excessivo. Este trabalho objetiva o desenvolvimento de uma metodologia de análise de materiais poliméricos avançados, especificamente fibras de poliaramida e materiais compósitos à base de fibra de carbono, em substituição a materiais tradicionais, utilizando modelos numéricos capazes de prever o comportamento da pressão de ruptura das carcaças e resistência a compressão radial do mangote, além da avaliação em fadiga dos cordonéis à base de poliaramida dessas novas estruturas. Modelos em meso-escala foram desenvolvidos utilizando conceitos de hiperelasticidade e de critérios de falha de materiais compósitos para previsão das tensões e deformações locais em regiões críticas do mangote. Análises numéricas foram realizadas via elementos finitos com o software comercial para auxiliar a elaboração dos modelos e a realização dos cálculos numéricos. Foram realizados ensaios experimentais para validação desses modelos numéricos, bem como para a previsão do comportamento estático e em fadiga dos materiais envolvidos. Foram desenvolvidos dois modelos. Em um modelo foi aplicado pressão interna no mangote para previsão de ruptura das carcaças no qual tem o objetivo de avaliar o desempenho dos novos reforços de poliaramida. No outro modelo foi aplicada uma carga radial na seção central do mangote para prever a resistência ao esmagamento, no qual tem o objetivo de avaliar o desempenho do componente de sustentação em material compósito de fibra de carbono. Os resultados dos modelos numéricos apresentaram boa concordância com os resultados experimentais em grande parte das análises. Também se observou que os novos materiais apresentam um grande potencial de substituição dos materiais tradicionais, bem como um excelente comportamento frente a carregamentos estáticos e dinâmicos envolvidos na aplicação, sendo verificada diminuição significativa de peso e aumento do desempenho. / Offloading hoses have been extensively used at offloading oil operations, especially in deep water, where there are variable static and cyclic loads due to the working environment. Despite the great demand for these structures, their behavior is little known and discussed in the literature due to the complexity. In addition, the materials used in this equipment may lead to a high number of failures, being often overestimated, leading to excessive weight. This work aims to develop a methodology for analysis of advanced polymeric materials, specifically polyaramide fibers and carbon fiber composite materials, in the substitution of traditional materials, using numerical models able to predict the static behavior of the burst pressure of the carcasses and radial compression strength of the hose. In addition, fatigue tests were performed to evaluate the polyaramide cords of these new structures. Meso-scale models were developed using advanced hyperplastic and composite failure criteria concepts to predict local stresses and strains in critical regions of the hose. Numerical analyses were performed using finite elements with commercial software to aid the development of models and to carry out numerical calculations. Several experimental tests were performed to validate numerical models, as well as to forecast the static and fatigue behavior of the materials used. Two models were developed. A model is used to predict the burst pressure of the hose in order to evaluate the performance of the new polyaramide reinforcements cords. In the other model, a radial load was applied in the central section of the hose to predict the crushing strength, in which it has the aim of evaluating the performance of the load-bearing component made with carbon fiber composite material. The results of the computer models showed good agreement with the experimental results in most analyses. It was also found that the studied materials offered considerable potential for the substitution of traditional materials, as well as an excellent behavior under static and dynamic loads related to this application, with a significant weight reduction and increased performance of the new configurations over traditional hoses.
95

Le football professionnel européen dans un système capitaliste financiarisé en crise : une approche régulationniste des facteurs de changement institutionnel / European professional football and the crisis of the financialised capitalism : a study of institutional change from the French Régulation theory

Bastien, Jérémie 05 December 2017 (has links)
L’idée que le football professionnel en Europe est en crise fait très largement consensus parmi les économistes. Dans notre thèse, nous montrons que ce diagnostic suppose de négliger un certain nombre d’éléments constitutifs de l’inscription du football dans le monde économique. C’est pourquoi, nous défendons que, loin d’être en crise, le football professionnel européen est, depuis les années 1980, dans une phase de très forte croissance. Pour ce faire, nous adoptons une démarche mésoéconomique régulationniste et procédons à une analyse systémique et multi-niveaux du football professionnel européen. Nous aboutissons ainsi à la caractérisation d’un « régime économique de fonctionnement » que nous qualifions de « financiarisé » compte tenu de l’instrumentalisation du football par des intérêts financiarisés et de leur influence sur les stratégies des acteurs traditionnels du football. Cette financiarisation du football engendre une forte instabilité de son régime puisque l’activité des clubs implique du déficit et du surendettement. En effet, l’incitation à la performance sportive (ligue ouverte), le fort pouvoir de négociation des joueurs (hold-up) et la souplesse de l’environnement réglementaire du football conduisent les clubs à des niveaux de dépenses élevés. Au contraire des « petits » clubs, cette situation n’est pas problématique pour les « grands » clubs, puisqu’ils sont soutenus par des agents à forte capacité de financement et tirent des revenus élevés de leur participation aux compétitions supranationales. Dans ce contexte, le régime est donc durable : sous l’effet de l’instabilité, les acteurs nouent de nouveaux compromis qui modifient les « dispositifs institutionnels » existants et rendent ainsi pérenne la logique de croissance en vigueur. Il y a donc régulation (au sens de la théorie de la régulation) du football. Il reste toutefois que ces modalités de régulation conduisent à accroître les inégalités entre les clubs et que cela pourrait, à terme, amener à une crise économique majeure du football professionnel européen. / Economists argue that the European professional football is in crisis. This thesis discusses this postulate by testing the relationship between the changes in football and the transformations of modern capitalism. Our methodology is based on a meso-level analysis from the French “Régulation theory” which provides a systemic and multilevel analysis. The thesis thus emphasizes how the progressive integration of financialised interests in football has an influence on the strategies of football traditional stakeholders. It actually shows that the financialisation process of the European professional football leads to growth since the 1980s. However, this growth is rather unstable because losses and indebtedness are part of clubs activity. The incentive for sports performance (open league), the players’ strong bargaining power (hold-up) and the flexibility of the regulatory environment are the main determinants of the clubs’ high spendings. Contrary to the “small” clubs, this situation is not a constraint for the “big” clubs thanks to the financial contributions they obtain from their owners, from their funding partners and from their participation to supranational competitions. In this environment and despite instability, the growth regime remains nevertheless sustainable. The stakeholders create new compromises to reduce imbalances: these compromises are the roots for new institutional arrangements that finally support the growth logic which is in place. There is therefore a “régulation” in European professional football, that is to say a process that contributes to the reproduction of the sector. However, this process paradoxically increases inequalities and may encourage the conditions for a major economic crisis.
96

Macular Pigment and Lens Optical Density Measurements-Evaluating a Flicker Machine with Novel Features

Mukherjee, Anirbaan 02 July 2015 (has links)
Age related macular degeneration (AMD) is one of the leading causes of blindness amongst the elderly. Macular pigment (MP) in the retina has been established to protect individuals against AMD. Improving levels of MP by diet or supplements is the constant quest of clinical practitioners and researchers, thus necessitating development of instruments capable of repeatable and reliable MP measurement. Cataract, a consequence of the rising opacity levels of the lens with age is one of the other major causes of blindness in the world. Mapcatsf, a LED-based microprocessor-controlled heterochromatic flicker photometer (HFP) using photopic vision is capable of measuring the levels of MP and the opacity of the lens in terms of optical density. Test-retest measurements conducted on 83 subjects were analyzed for repeatability in macular pigment optical density (MPOD) measurements. Reliability of the lens optical density (LOD) measurements were tested and compared with those obtained at absolute scotopic thresholds for 25 individuals. A supplement study with 32 individuals both in the young (50) age groups for 6 months further established Mapcatsf’s capacity to monitor changing levels of MP in individuals. As an overall outcome, high levels of repeatability and reliability were obtained in MPOD and LOD measurements establishing Mapcatsf as an instrument for use in clinical settings in the future.
97

The Determinants of the Use of Telemedicine in Senegal

Ly, Birama Apho January 2016 (has links)
Introduction In Senegal, as in many countries, physicians are unevenly distributed. This situation leads to health inequalities, but the solutions adopted to distribute physicians equitably do not give satisfactory results. This situation pushes decision-makers and researchers to look for other solutions such as telemedicine. This technology-based solution is considered to be a good means to improve physician recruitment and retention in underserved areas, thus improving access to healthcare in these areas, but it is still underused in Senegalese health facilities. Objective This study aimed to identify the determinants of the use of telemedicine in Senegal. More specifically, it aimed to identify the individual (micro) and contextual (meso and macro) factors that influence the use of telemedicine in Senegal. Method The study involved mixed methods: a descriptive qualitative study involving individual interviews and a cross-sectional quantitative study involving questionnaires. The first method was used to study the individual (micro) factors such as physicians’ beliefs on the use of telemedicine and physicians’ perception of the impact of telemedicine on their recruitment and retention in underserved areas. It was also used to study the contextual meso (technical, organizational and ethical) and macro (financial, political, legal and socioeconomic) factors that influence the use of telemedicine. The second method was used to study participants’ intention to use telemedicine in their professional activities, another individual (micro) factor. This study included physicians working in public hospitals, those working in district health, and telemedicine projects managers. Qualitative data was collected through individual interviews, transcribed and imported into NVivo 10 where they were coded thematically. Quantitative data was collected by administering questionnaires and analyzed using SPSS 23. Results The results showed that telemedicine could contribute to, but could not guarantee the recruitment and retention of Senegalese physicians in underserved areas. It was found that physicians in Senegal have both positive and negative behavioural, normative and control beliefs that can encourage or discourage them from using telemedicine in their professional practice. The most salient behavioural beliefs were that telemedicine makes experts’ opinions accessible across distances (positive behavioural belief), but could lead to medical errors (negative behavioural belief). The most common normative beliefs were that their patients would most probably approve the use of telemedicine (positive normative belief) while their colleagues working in the public sector might disapprove of it (negative normative belief). The most reported control beliefs were that the use of telemedicine is easy (positive control belief), but could be time-consuming (negative control belief). For physicians in Senegal, the findings also demonstrate that the probability that they will use telemedicine in their professional activities is moderate and influenced by their perceived behavioural control which, in turn, is influenced by their positive and negative control beliefs. Finally, the results demonstrate that many contextual meso (technical, organizational and ethical) and macro (financial, political, legal and socioeconomic) factors influence the use of telemedicine in Senegal. Conclusion The results of this study can inform the choice of telemedicine development strategies. These strategies can help to promote the use of telemedicine in Senegal, which in turn can help to increase physician recruitment and retention in underserved areas, resulting in better access to healthcare and, and as a result improved population health.
98

Compréhension et modélisation des mécanismes de refermeture de porosité dans les procédés de mise en forme des métaux à chaud / Understanding and modeling of void closure mechanisms in hot metal forming processes

Saby, Michel 11 December 2013 (has links)
Lors de l'élaboration de pièces métalliques de grandes dimensions, la présence interne de pores est habituellement observée. Ces défauts internes sont généralement refermés lors des premières passes de transformation à chaud. Il y a cependant à l‘heure actuelle un manque de connaissance sur les mécanismes mis en jeu lors de cette refermeture, et par conséquent aucune prédiction précise possible et un taux de rebut assez important. Le travail présenté dans ce manuscrit vise à mieux comprendre les mécanismes de refermeture en identifiant les paramètres procédés, matériaux et morphologiques clés lors de la refermeture. Ce travail s'est déroulé dans le cadre d'un consortium industriel impliquant six partenaires. La problématique industrielle est donc particulièrement variée en termes de matériaux, de procédés et d'états initiaux de pores.Une étude approfondie des modèles existants dans la littérature est d'abord présentée. Les deux familles d'approches utilisées sont discutées : l'approche explicite en champ complet, et l'approche micro-analytique. Il est montré que ces deux approches ne sont pas suffisantes pour établir un modèle de prédiction dont la précision réponde aux enjeux industriels.Une nouvelle approche est donc proposée dans cette thèse à l'échelle mésoscopique. Les mécanismes de refermeture sont étudiés à l'échelle d'un volume élémentaire représentatif (VER), permettant une description 3D particulièrement précise des mécanismes locaux, tout en appliquant des conditions aux limites représentatives des états mécaniques mis en jeu à l'échelle macroscopique.Les mécanismes locaux ont été étudiés au moyen d'une vaste campagne de simulations éléments-finis 3D à l'échelle d'un VER. Les paramètres étudiés sont : les paramètres matériaux, la morphologie du pore, et le chargement thermomécanique subit durant la déformation. L'étude a montré que la morphologie et l'état de contraintes sont de premier ordre sur le comportement en refermeture, et que les paramètres matériaux sont de second ordre. Les influences des paramètres de premier ordre ont ensuite été quantifiées afin de proposer un modèle de prédiction de refermeture robuste. La morphologie du pore est exprimée par le biais de ses dimensions équivalentes (rapports d'élongations tridimensionnels) et de son orientation par rapport à la direction principale de déformation. L'état de contraintes est exprimé par le taux de triaxialité des contraintes.Le modèle a finalement été implémenté dans un code éléments finis de mise en forme et une validation sur cas industriels est présentée afin d'évaluer les bénéfices obtenus par ce nouveau modèle par rapport aux modèles de la littérature. Une validation expérimentale a également été menée par le biais d'essais d'écrasements d'échantillons poreux dont l'état de porosité a été mesuré par micro-tomographie aux rayons X avant et après les essais. / During production of large metal workpieces, an internal presence of voids is usually observed. Such internal defaults are generally closed up during the first passes of hot forming processes. Yet, there is at present a lack of knowledge regarding void closure mechanisms and there is no reliable model that can accurately predict void closure. The amount of non-deliverable products is consequently relatively high. The present work aims to better understand void closure mechanisms with respect to the involved materials, processes and voids' morphological parameters. This work was supported by an industrial consortium involving six partners. The industrial issues were thus particularly diversified in terms of materials, processes and initial void states.An extensive study regarding existing models in the literature is first presented. Two main approaches are discussed: the explicit full-field approach and the micro-analytical approach. It is shown that none of both approaches is sufficient to precisely predict void closure according to the industrial issues.A new approach is thus proposed at the mesoscale. Void closure mechanisms are studied using a representative volume element (RVE). Using this approach an accurate tridimensional description of the void state can be obtained at the RVE scale. Boundary conditions can also be imposed in order to accurately represent thermomechanical conditions from the macro-scale.Local mechanisms of void closure are studied using a large campaign of 3D finite element simulations at the RVE-scale. The studied parameters are: the materials parameters, the void's morphology and the thermomechanical loading that a void might undergo during hot forming processes. The study shows that both the void's morphology and the stress state exhibit a first-order influence on void closure. Materials parameters exhibit a second-order influence on void closure. A new reliable prediction model is thus proposed with respect to the first-order parameters. The void's morphology is quantitatively studied in terms of equivalent dimensions (tridimensional aspect ratios), and orientation (with respect to principal deformation direction). The stress state is expressed using the stress triaxiality ratio.The proposed model was finally implemented in a material forming finite element software. Validation cases are presented using industrial processes in order to highlight the benefits and limitations of this new model with respect to the existing models from the literature. An experimental validation was also performed using compression tests of porous samples. The samples were examined using X-ray micro-tomography before and after compression.
99

Uticaj brzine hlađenja polutki, vremena otkoštavanja post mortem i postupka salamurenja na kvalitet i bezbednost kuvane šunke / Effect of chilling rate of carcasses, time of deboning post mortem and way of curingon quality and safety of cooked ham

Tomović Vladimir 15 May 2009 (has links)
<p>Cilj ovog rada je bio de se utvrdi uticaj brzog vazdu&scaron;nog hlađenja polutki (na &ndash;31&deg;C do cca 4 sata, a zatim na 2 do 4&deg;C do 8, odnosno do 24 sata post mortem), vremena otko&scaron;tavanja post mortem (8 i 24 sata post mortem), nakon brzog hlađenja, i postupka salamurenja (bez ili sa vakuumom) proizvedenog svinjskog mesa (M. semimembranosus) na kvalitet i bezbednost kuvane &scaron;unke (konzervi od mesa u komadima), odnosno postavljen je zadatak razvoja novog proizvodnog procesa kuvane &scaron;unke koji će počivati na značajnoj racionalizaciji tehnolo&scaron;kog postupka, a čime bi se ostvarila i određena ekonomska dobit, uz postizanje vrhunskog kvaliteta proizvoda.<br />Da bi ovako postavljeni zadatak dao očekivane rezultate najpre je ispitan uticaj brzog hlađenja polutki i vremena otko&scaron;tavanja post mortem, nakon brzog hlađenja, na tehnolo&scaron;ki, nutritivni i senzorni kvalitet i bezbednost svinjskog mesa (M. semimembranosus), namenjenog proizvodnji ovog proizvoda. Analizom dobijenih rezultata zaključeno je da se brzim hlađenjem može obezbediti otko&scaron;tavanje polutki 8 sati post mortem, sa internom temperaturom manjom od 7&deg;C, uz značajno smanjenje tro&scaron;kova rada, kala hlađenja i udela mesa (M. semimembranosus) blede boje, odnosno zaključeno je da su brzo hlađeni mi&scaron;ići već do 8 sati post mortem prevedeni u stanje podesno za salamurenje, čime je dobijena sirovina potrebnih svojstava za izradu kuvane &scaron;unke.<br />Od ovako proizvedenog mesa (M. semimembranosus), nezavisno od postupka salamurenja (sa ili bez vakuuma), može se proizvesti kuvana &scaron;unka vrhunskog kvaliteta, &scaron;to potvrđuju rezultati ispitivanja kvaliteta kuvanih &scaron;unki proizvedenih od ove sirovine, pri čemu treba istaći da su utvrđene izvesne razlike kod pojedinih faktora kvaliteta kuvanih &scaron;unki prvenstveno rezultat faktora proizvodnje (na primer, operacije salamurenja), odnosno jo&scaron; uvek nestandardnog postupka proizvodnje ovih proizvoda (na primer, neujednačeno ubrizgavanje salamure). Dodatnim izmenama u tehnologiji salamurenja proizvedena je kvalitetna konzerva od mesa u komadima od ostataka mesa buta, uključujući i izdvojeno meso slabijeg kvaliteta (M. semimembranosus), i na taj način je samo jo&scaron; dodatno potvrđeno da je moguće značajno racionalizovati proizvodnju kuvane &scaron;unke uz valorizaciju celokupne muskulature buta.</p> / <p>The aim of the work was to determine the effect of rapid chilling of carcasses (at -31&deg;C up to cca.<br />4 hours, and at 2 to 4&deg;C til 8 i.e. 24 hours post mortem), time of deboning post mortem (8 and 24<br />hours post mortem), after rapid chilling, and way of curing (with and without vacuum) of processed<br />pork (M. semimembranosus) on quality and safety of cooked ham i.e. a task was set to develop a new<br />process of cooked ham production based on significant rationalization of the technological procedure,<br />enabling a certain economic profit, and achieving first class product quality.<br />The effect of rapid chilling of carcasses and time of deboning post mortem, after rapid chilling, on<br />technological, nutritive and sensory quality and safety of pork (M. semimembranosus) intended for the<br />production of cooked ham was investigated. The analysis of obtained results showed that deboning of<br />carcasses is possible up to 8 hours post mortem due to rapid chilling, achieving internal temperatures<br />lower than 7&deg;C, with significantly lower working co sts, weight loss and share of pale meat (M.<br />semimembranosus), i.e. the conclusion is that rapid chilled muscles 8 hours post mortem were in state<br />convenient for curing, obtaining the raw material of required characteristics for cooked ham<br />production.<br />First class quality cooked ham can be produced from pork (M. semimembranosus) obtained in<br />this way, irrespective of curing process (with or without vacuum), as supported by the results of quality<br />investigation of the obtained final product. Some differences found between certain quality factors of<br />cooked ham are the result of processing factors (curing processes, for example), i.e. of still nonstandard<br />production way of this product (for example, uneven injecting of brine). Certain changes of<br />curing technology enabled the production of quality cooked ham from rest ham meat and the<br />separated lower quality meat (M. semimembranosus). These results additionally confirm the possibility<br />of significant rationalization of cooked ham production i.e. possible valorization of the whole amount of<br />ham meat.</p>
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Simulations Numériques Directes d’une méso-chambre de combustion : Mise en oeuvre et analyses / Direct Numerical simulations of a meso-scale combustion chamber : Implementation and Analysis

Cuif Sjöstrand, Marianne 25 October 2012 (has links)
La méso-combustion est le régime de combustion où la taille caractéristique du domaine est juste supérieure à la distance de coincement de la flamme , typiquement de l'ordre du centimètre. La difficile réalisation de systèmes de combustion fonctionnant en ce régime de flamme particulier suscite l'intérêt : il devient alors possible de tirer parti de la haute densité énergétique des hydrocarbures pour concevoir des systèmes de production d'énergie plus compacts. Nous nous intéressons à la réalisation de calculs DNS compressibles d'une chambre de combustion cubique de 8 x 10 x 8 mm3. Ce travail présente autant la mise en œuvre des calcules, en particulier la problématique de la condition frontière mur, que les résultats obtenus. Ces derniers nous permettent d'analyser la phénoménologie complexe de cet écoulement réactif confiné et serviront de base à des modélisations futures. / Meso-combustion can be defined as the combustion regime where the involved lenghts scales are close but slightly larger than the quenching distance of the flame, tipically smaller than a cm. By taking advantage of the high energetic density of liquid hydrocarbons, it would become possible to build small-sized combustion-based long-lived lighter electrical power systems. However combsution phenomena at these meso-scales have their own shortcomings. Indeed, by decreasing the system size, the usual phenomenological balance betwenne chemical reactions, mixing, turbulence and heat transfer is changed. In the present work, we focus on the DNS calculation of a cubic meso-combsution chamber of 8 x 10 x 8 mm3. This works presents the implementation of the numerical strategy used, with a specific attention to the no-slip wall compressible boundary condition. We then present an analysis of this particular reactive flow. The results are useful for future modeling of such a combustor.

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