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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.
671

Modéliser les changements mineurs et majeurs d'individus en interactions : application à la conversion à l'agriculture biologique / Minor and major changes model of interacting individuals : application to the conversion to organic farming

Xu, Qing 26 November 2018 (has links)
Nous connaissons depuis plus d’un siècle des bouleversements climatiques, socio-économiques et sociétaux de plus en plus fréquents et intenses. L’adaptation à ce contexte incertain, pour envisager l’avenir de façon durable, est un défi particulièrement important. L’agriculture est au cœur de ce défi et de la réflexion sur les modes d’adaptation. Les anthropologues ont récemment identifié deux types de changements de l’agriculteur: le changement mineur (en accord avec le comportement normatif de référence), et le changement majeur (changement profond, remise en cause des normes majoritaires permettant l’adoption de comportements innovants). Ces deux types de changement sont très proches de l’adaptation incrémentale et de l’adaptation transformationnelle qui sont définis tant pour des individus que pour des institutions locales, nationales ou internationales … Nous proposons un modèle individu-centré de l’adaptation des agriculteurs qui intègre dynamiquement changements mineurs et majeurs, en nous focalisant sur la dimension psycho-sociale de ces changements. Nous appliquons notre modèle à la question, de la conversion à l’agriculture biologique des éleveurs laitiers français. Cette transition a en effet été généralement caractérisée comme un changement majeur, ou une adaptation transformationnelle, et s’avère donc pertinente pour tester notre modèle. Le modèle d’agriculteur est en général dans un régime stable durant lequel seuls des changements mineurs sont opérés. Ces changements sont menés en imitant des comportements adoptés par les agriculteurs les plus crédibles. La crédibilité d’un agriculteur pour un autre est d’autant plus forte que son volume produit est supérieur à celui de cet agriculteur. Ces changements se traduisent concrètement par des modifications des volumes produits qui correspondent à des choix de pratiques plus ou moins intensifs.Le modèle peut passer d’un régime stable à un autre en transitant par un changement majeur impliquant de changer la hiérarchie des importances, accordées aux dimensions « productiviste » et « environnementale », qui pondèrent son évaluation des résultats de son mode de production (par exemple : conventionnel ou biologique). Le calcul de son évaluation utilise la théorie de l’action raisonnée. Il permet à l’agriculteur de déterminer sa satisfaction, à partir de ses résultats précédents, et de ses résultats comparés à ceux de ses pairs crédibles, en tenant compte de l’importance accordées à chaque dimension d’évaluation. Lorsqu’un agriculteur est insatisfait de son mode de production courant, il évalue sa satisfaction potentielle pour un autre mode de production, et adopte ce dernier si son gain de satisfaction est supérieur à un seuil. Il change alors la hiérarchie des importances accordées à ses dimensions d’évaluation pour être en accord avec le mode adopté. Un agriculteur biologique accordera ainsi par exemple une importance plus forte à la dimension environnementale qu’à la dimension productiviste. Ce changement implique alors une réévaluation tant de la crédibilité de ses pairs que de leurs pratiques. (...) / For more than a century, climatic, socio-economic and societal changes are more and more frequent and intense. Adapting to this uncertain context to envisage a sustainable future is a particularly important challenge. Agriculture is at the heart of this challenge and the reflection on the modes of adaptation. Anthropologists have recently identified two types of farmer changes: minor change (consistent with normative behavior), and major change (deep change, challenge the majority norms allowing adoption of innovative behaviors). These two types of change are very close to the incremental adaptation and the transformational adaptation that are defined for individuals as well as for local, national or international institutions.We propose an individual-based model to study farmers’ adaptations that dynamically integrates minor and major changes. We focus on the social-psychological dimension of these changes. Our model is applied to the question of French dairy farmers’ conversions to organic farming. This transition has been characterized as a major change, or a transformational adaptation, and is therefore relevant to test our model.A farmer stays generally in a stable regime doing only minor changes. These changes are carried out by imitating the practices of the most credible farmers. The credibility of one farmer given to another is larger if his (her) produced volume is greater than that of this farmer. These changes are shown by concrete changes of produced volumes, which correspond to more or less intensive choices of practice.In the model, a farmer passes from one stable regime to another through a major change involving a change of his (her) hierarchy of importance over the "productivist" and "environmental" evaluative dimensions. The importance weights his (her) evaluation of the results according to the mode of production (for example: conventional or organic). The computation of the evaluation is based on the theory of reasoned action. This evaluation shows a farmer’s satisfaction that is based on his (her) previous results and his (her) results compared to those of his (her) credible peers, taking into account the importance given to each dimension of evaluation. When a farmer is dissatisfied with his (her) current mode of production, he (she) evaluates his (her) potential satisfaction with another mode of production, and adopts the latter if his (her) satisfaction gain is above a threshold. He (she) then changes the importance hierarchy given to the evaluation dimensions to be in agreement with the adopted mode. For example, an organic farmer will given more importance to the environmental dimension than to the productivist dimension. This change implies a reassessment of both the credibility given to his (her) peers and their practices. (...)
672

A Comparative Study of the Social Welfare Provided by Three Christian Churches in Accra, Ghana

Lidzén, Linda January 2008 (has links)
<p>The family is the first and oldest provider of social welfare in the West African country of Ghana. However, colonisation and urbanisation has changed that role and today additional providers of social welfare can be found; the government, religious organisations (churches etc), non-religious organisations and Non Governmental Organisations (NGOs).</p><p>This study will confirm the claim that the church takes on a role as a surrogate family and that it steps in where the government is not present, doing social work which is intended for the government. The study will also investigate what kind of social work the churches carry out (including what they put their focus on, which is dependent on their finance and location) and how these different projects are financed.</p><p>The study was conducted during a six week period in Accra, capital of Ghana. Representatives from three Christian congregations (Presbyterian Church of Ghana in Kaneshie, Global Evangelical Church in Kotobabi and International Central Gospel Church in Teshie) were interviewed, as was Dr. Ayidiya at the Department of Social Work, University of Ghana, in order to get background information on the present social welfare system in Ghana.</p>
673

Genetic analysis of earliness traits in chickpea (<i>Cicer arietinum</i> L.)

Kabeta, Yadeta Anbessa 31 July 2007
The latter part of the reproductive growth phase in chickpea (<i>Cicer arietinum</i> L.) often coincides with declining temperature and wet conditions in western Canada, in sharp contrast to many other growing environments. This exacerbates the indeterminate nature of the crop, leading to excessive canopy development, and subsequently resulting in delayed maturity. The objectives of this study were to: i) determine the genetic relationships of short internode, double podding and early flowering traits with earliness of crop maturity; ii) determine the genetic control of major earliness traits in chickpea; iii) assess the patterns of post-flowering dry matter accumulation and partitioning to reproductive parts as related to earliness. <p>The results showed that double podding significantly reduced the number of days taken to maturity, under the conditions where this trait was sufficiently expressed. The best double podding genotypes, i.e. those with 1535% of the podded nodes bearing double pods, were about one week earlier than their single podding counterparts and standard checks. A physiological study revealed that the double podding parental genotype 272-2 partitioned a relatively greater proportion (about 58%) of the total dry matter to pods compared to 4254% in the single podding genotypes. Double podding increased the total number of pods set, and thus the increased demand for assimilates may have precluded further production of stems and leaves, resulting in an earlier transition of reproductive growth to physiological maturity. Days to flowering was positively associated with days to maturity, and partial path analysis revealed that days to flowering contributed to days to maturity indirectly via days to first pod maturity. Days to flowering explained 32% of the variation in days to first pod maturity. However, the short internode trait had an undesirable effect, in that all the short internode segregants were too late to mature. <p>Genetic studies revealed that days to flowering was determined by two major genes plus polygenes in chickpea in the short-season temperate environment of western Canada. The two major genes control over 65% of the phenotypic variation. Also, the additive component of genetic variance was significant for days to first podding, days to first pod maturity, reproductive period, and days to maturity; which is desirable for development of superior inbred cultivars of chickpea. These key phenological traits are interrelated but could be manipulated separately in the breeding process. Additional gain in earliness of crop maturity may be achieved through combined selection for these traits.
674

Building an Landscape in Yogyakarta, Indonesia : -A study of Ecological planning for Building and Landscape.

Svensson, Pia-Lice January 2008 (has links)
The objective with this final thesis is to show how to work and help as an engineer by an ecological planning for building and landscape in an Asian and Muslim country like Indonesia. The qualitative working method that was used highlights the importance of field trips and free structured interviews. Talking to the people involved and seeing the specific areas gives understanding you can not get by studying literature.   The importance of all the work areas in the process of exploiting an area formulates the problem. This is later investigated and practiced in Yogyakarta, Indonesia and was encourage by the SIDA scholarship “MFS”. Indonesia is a big country divided in 17500 islands but there are more that are different to Sweden. The author describes the unwritten rules, religions and the climate difference and also the working process for work and study on Java in Indonesia. The main part shows and explains the result; a proposal on how an existing student accommodation in the city Yogyakarta in Indonesia could be renewed with an ecological plan for its building and landscape. Conclusions and thoughts are made by the author about the possibilities for the future. Potential exchange of knowledge, labor and other services should be made between schools in Sweden and Indonesia and also help-organizations. / Detta examensarbete syftar till att visa hur man kan arbeta och hjälpa till som byggingenjör genom ett ekologiskt plannerande för byggande och landskap i ett land som Indonesien. Vikten av alla arbetsområden i processen för att exploatera ett område formulerade problemmet. Detta undersöktes och prövades sen i Yogyakarta, Indonesien och uppmuntrades av SIDA stipendiet "MFS". Den kvalitativa arbetsmetoden som använts belyser vikten av studie resor och fristrukturerade intervjuer. Att prata med människorna som är involverade och se platserna ger en förståelse som inte är möjlig att få om det enbart görs literatur studie. Indonesien är stort land och är uppdelat i 17500st öar men det är mer som är olikt från Sverige. Författaren beskriver de annorlunda oskrivna regler, religioner och klimat och även arbets processen för att jobba eller studera på Java i Indonesien. Huvudelen visar och förklarar resultatet; ett förslag till hur ett befintligt student boende i staden Yogyakarta i Indonesien kan förnyas med en ekologisk plann för byggnad och landskap. Slutsattser och tankar är slutnligen formulerade av författaren om möjligheter i framtiden. Utbytte av kunskap, arbete och andra tjänster bör utövas mellan skolor i Sverigeoch Indonesien men även hjälporganisationer.
675

Genetic analysis of earliness traits in chickpea (<i>Cicer arietinum</i> L.)

Kabeta, Yadeta Anbessa 31 July 2007 (has links)
The latter part of the reproductive growth phase in chickpea (<i>Cicer arietinum</i> L.) often coincides with declining temperature and wet conditions in western Canada, in sharp contrast to many other growing environments. This exacerbates the indeterminate nature of the crop, leading to excessive canopy development, and subsequently resulting in delayed maturity. The objectives of this study were to: i) determine the genetic relationships of short internode, double podding and early flowering traits with earliness of crop maturity; ii) determine the genetic control of major earliness traits in chickpea; iii) assess the patterns of post-flowering dry matter accumulation and partitioning to reproductive parts as related to earliness. <p>The results showed that double podding significantly reduced the number of days taken to maturity, under the conditions where this trait was sufficiently expressed. The best double podding genotypes, i.e. those with 1535% of the podded nodes bearing double pods, were about one week earlier than their single podding counterparts and standard checks. A physiological study revealed that the double podding parental genotype 272-2 partitioned a relatively greater proportion (about 58%) of the total dry matter to pods compared to 4254% in the single podding genotypes. Double podding increased the total number of pods set, and thus the increased demand for assimilates may have precluded further production of stems and leaves, resulting in an earlier transition of reproductive growth to physiological maturity. Days to flowering was positively associated with days to maturity, and partial path analysis revealed that days to flowering contributed to days to maturity indirectly via days to first pod maturity. Days to flowering explained 32% of the variation in days to first pod maturity. However, the short internode trait had an undesirable effect, in that all the short internode segregants were too late to mature. <p>Genetic studies revealed that days to flowering was determined by two major genes plus polygenes in chickpea in the short-season temperate environment of western Canada. The two major genes control over 65% of the phenotypic variation. Also, the additive component of genetic variance was significant for days to first podding, days to first pod maturity, reproductive period, and days to maturity; which is desirable for development of superior inbred cultivars of chickpea. These key phenological traits are interrelated but could be manipulated separately in the breeding process. Additional gain in earliness of crop maturity may be achieved through combined selection for these traits.
676

A Comparative Study of the Social Welfare Provided by Three Christian Churches in Accra, Ghana

Lidzén, Linda January 2008 (has links)
The family is the first and oldest provider of social welfare in the West African country of Ghana. However, colonisation and urbanisation has changed that role and today additional providers of social welfare can be found; the government, religious organisations (churches etc), non-religious organisations and Non Governmental Organisations (NGOs). This study will confirm the claim that the church takes on a role as a surrogate family and that it steps in where the government is not present, doing social work which is intended for the government. The study will also investigate what kind of social work the churches carry out (including what they put their focus on, which is dependent on their finance and location) and how these different projects are financed. The study was conducted during a six week period in Accra, capital of Ghana. Representatives from three Christian congregations (Presbyterian Church of Ghana in Kaneshie, Global Evangelical Church in Kotobabi and International Central Gospel Church in Teshie) were interviewed, as was Dr. Ayidiya at the Department of Social Work, University of Ghana, in order to get background information on the present social welfare system in Ghana.
677

Family matters in Roman Asia Minor : elite identity, community dynamics and competition in the honorific inscriptions of imperial Aphrodisias

Morgan, Ann Marie, active 2014 20 June 2014 (has links)
In the city centers of Roman Asia Minor, honorific monuments, which consisted of a portrait sculpture and biographical inscription, filled the agoras, aedicular facades, and colonnaded avenues. While some monuments were for Roman emperors and magistrates, the majority celebrated and memorialized the most important members of the local community, male and female, individuals who held public offices, sponsored festivals, and funded large scale construction projects. Honorific monuments were collaborative productions that involved civic institutions, the honored benefactor, and the family or friends of the honorand. Because of the multiplicity of actors involved in the honorific process, an examination of honorific inscriptions allows for a discussion of identity construction at different scales from the individual honorand and his or her family to an entire civic community. In a city in Asia Minor during the empire, the identities conveyed included Roman imperial allegiances, Greek cultural values, and ties to the local community, often combined in compositions that justified claims of status or fulfilled political ambitions. This dissertation investigates the honorific inscriptions from one city in Asia Minor, Aphrodisias, from the mid-1st century BCE to the mid-3rd century CE, which consists of 206 instances of honor for 183 local Aphrodisians. The analysis examines developments in elite self-fashioning and the evolution of the reciprocal relationship between a community and its benefactors, with particular focus on references to ancestry and familial connections in the language of the inscriptions. The evidence indicates that the Aphrodisian elite deployed epigraphic formulations that mention family background and Roman connections in order to construct composite cultural identities and to affirm their place among the city’s aristocratic factions. The contextualization of these texts in an historical and archaeological framework demonstrates that the observed epigraphic changes responded both to internal factors, such as demographic shifts, and external ones, such as the spread of Roman citizenship. This analysis highlights the internally-stratified and competitive aristocratic order that functioned in Imperial Aphrodisias and articulates how the elite employed references to ancestral background, local ties, and Roman familial connections strategically in ways that had tangible impacts on the landscape of the city. / text
678

Lien entre la légitimité perçue de la violence subie dans l’enfance et les comportements violents à l’égard des enfants du point de vue de pères québécois

Jamal, Farah 10 1900 (has links)
La transmission intergénérationnelle de la violence envers les enfants et les perceptions reliées aux expériences personnelles de violence dans l’enfance ont été peu étudiées auprès de la population générale et encore moins auprès des pères. L’objectif de la présente étude est de déterminer le lien entre, d’une part, la fréquence rapportée de la violence physique sévère vécue dans l’enfance et la légitimité perçue de cette violence et d’autre part, la violence physique mineure et psychologique envers les enfants au sein de la famille actuelle de 204 pères québécois. Les données sont issues de l’enquête sur la violence familiale dans la vie des enfants du Québec réalisée en 2004 par l’Institut de la Statistique du Québec. Il y a un lien significatif entre la fréquence rapportée de la violence physique sévère vécue dans l’enfance et sa légitimité perçue, ainsi qu’avec la violence envers les enfants dans la famille actuelle des pères. Les pères rapportant avoir souvent ou très souvent vécu de la violence physique sévère dans l’enfance ont actuellement des enfants qui vivent plus de violence psychologique que ceux qui en ont parfois vécu. Plus les pères considèrent la violence physique sévère vécue dans l’enfance comme méritée, plus leurs enfants vivent de la violence psychologique. Enfin, les enfants des pères qui considèrent la violence subie comme parfois méritée vivent moins de violence physique mineure que ceux des pères qui la considèrent comme souvent ou très souvent méritée. Les implications pour la recherche et la pratique sont discutées. / Intergenerational patterns of violence against children and perceptions of childhood abuse have not been studied a lot among general population or fathers. The objective of the present study is to determine the link between frequencies of childhood severe physical violence and its perceived legitimacy (first), and minor physical and psychological violence against children in actual family (second) in a sample of 204 fathers from Quebec. Results indicate a significant link between frequencies of childhood severe physical violence and its perceived legitimacy, and violence against children in actual family. Fathers who have often or very often lived childhood severe physical violence have children who suffer more psychological violence than fathers who have lived it sometimes. The more fathers think that childhood violence was deserved, the more their children suffer psychological violence. Finally, children of fathers who think that childhood severe physical violence was sometimes deserved suffer less minor physical violence than those of fathers who think that it was often or very often deserved. Implications for research and practice are discussed.
679

Deep burn strategy for the optimized incineration of reactor waste plutonium in pebble bed high temperature gas–cooled reactors / Serfontein D.E.

Serfontein, Dawid Eduard. January 1900 (has links)
In this thesis advanced fuel cycles for the incineration, i.e. deep–burn, of weapons–grade plutonium, reactor–grade plutonium from pressurised light water reactors and reactor–grade plutonium + the associated Minor Actinides in the 400 MWth Pebble Bed Modular Reactor Demonstration Power Plant was simulated with the VSOP 99/05 diffusion code. These results were also compared to the standard 9 g/fuel sphere U/Pu 9.6% enriched uranium fuel cycle. The addition of the Minor Actinides to the reactor–grade plutonium caused an unacceptable decrease in the burn–up and thus an unacceptable increase in the heavy metal (HM) content in the spent fuel, which is intended for direct disposal in a deep geological repository, without chemical reprocessing. All the Pu fuel cycles failed the adopted safety limits in that either the maximum fuel temperature of 1130°C, during normal operation, or the maximum power of 4.5 kW/sphere was exceeded. All the Pu cycles also produced positive Uniform Temperature Reactivity Coefficients, i.e. the coefficient where the temperature of the fuel and the graphite moderator in the fuel spheres are varied together. these positive temperature coefficients were experienced at low temperatures, typically below 700°C. This was due to the influence of the thermal fission resonance of 241Pu. The safety performance of the weapons–grade plutonium was the worst. The safety performance of the reactor–grade plutonium also deteriorated when the heavy metal loading was reduced from 3 g/sphere to 2 g or 1 g. In view of these safety problems, these Pu fuel cycles were judged to be not licensable in the PBMR DPP–400 reactor. Therefore a redesign of the fuel cycle for reactor–grade plutonium, the power conversion system and the reactor geometry was proposed in order to solve these problems. The main elements of these proposals are: v 1. The use of 3 g reactor–grade plutonium fuel spheres should be the point of departure. 232Th will then be added in order to restore negative Uniform Temperature Reactivity Coefficients. 2. The introduction of neutron poisons into the reflectors, in order to suppress the power density peaks and thus the temperature peaks. 3. In order to counter the reduction in burn–up by this introduction of neutron poisons, a thinning of the central reflector was proposed. / Thesis (PhD (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012.
680

Deep burn strategy for the optimized incineration of reactor waste plutonium in pebble bed high temperature gas–cooled reactors / Serfontein D.E.

Serfontein, Dawid Eduard. January 1900 (has links)
In this thesis advanced fuel cycles for the incineration, i.e. deep–burn, of weapons–grade plutonium, reactor–grade plutonium from pressurised light water reactors and reactor–grade plutonium + the associated Minor Actinides in the 400 MWth Pebble Bed Modular Reactor Demonstration Power Plant was simulated with the VSOP 99/05 diffusion code. These results were also compared to the standard 9 g/fuel sphere U/Pu 9.6% enriched uranium fuel cycle. The addition of the Minor Actinides to the reactor–grade plutonium caused an unacceptable decrease in the burn–up and thus an unacceptable increase in the heavy metal (HM) content in the spent fuel, which is intended for direct disposal in a deep geological repository, without chemical reprocessing. All the Pu fuel cycles failed the adopted safety limits in that either the maximum fuel temperature of 1130°C, during normal operation, or the maximum power of 4.5 kW/sphere was exceeded. All the Pu cycles also produced positive Uniform Temperature Reactivity Coefficients, i.e. the coefficient where the temperature of the fuel and the graphite moderator in the fuel spheres are varied together. these positive temperature coefficients were experienced at low temperatures, typically below 700°C. This was due to the influence of the thermal fission resonance of 241Pu. The safety performance of the weapons–grade plutonium was the worst. The safety performance of the reactor–grade plutonium also deteriorated when the heavy metal loading was reduced from 3 g/sphere to 2 g or 1 g. In view of these safety problems, these Pu fuel cycles were judged to be not licensable in the PBMR DPP–400 reactor. Therefore a redesign of the fuel cycle for reactor–grade plutonium, the power conversion system and the reactor geometry was proposed in order to solve these problems. The main elements of these proposals are: v 1. The use of 3 g reactor–grade plutonium fuel spheres should be the point of departure. 232Th will then be added in order to restore negative Uniform Temperature Reactivity Coefficients. 2. The introduction of neutron poisons into the reflectors, in order to suppress the power density peaks and thus the temperature peaks. 3. In order to counter the reduction in burn–up by this introduction of neutron poisons, a thinning of the central reflector was proposed. / Thesis (PhD (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012.

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