872 resultados para dominance


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Ce mémoire étudie la situation de l'accès à l'éducation élémentaire au Sénégal en procédant à une analyse des dépenses publiques associée à la dominance stochastique. Je montre ainsi qu'en général, les inégalités dans l'accès à l'enseignement de base ont diminué entre 2001 et 2006. En divisant par la région et le genre, je relève aussi que de grandes disparités entre les milieux urbain et rural existent toujours au Sénégal, mais que les écarts entre les filles et les garçons sont pratiquement nuls, sauf à la campagne où les filles les plus pauvres constituent le groupe fréquentant le moins l'école publique dans tout le pays. Ces résultats démontrent que les analyses d'inégalités dans l'accès aux services publics doivent impérativement tenir compte des inégalités régionales. De plus, une comparaison plus superficielle avec 1992 permet de constater qu'à l'échelle nationale, la situation n'a cessé de progresser depuis ce temps, mais qu'en s'attardant à chaque région, on aperçoit des changements importants dans la tendance de chacune d'entre elles.

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In this paper, we address the problem of sharing a wireless channel among a set of sporadic message streams where a message stream issues transmission requests with real-time deadlines. We propose a collision-free wireless medium access control (MAC) protocol which implements static-priority scheduling, supports a large number of priority levels and is fully distributed. It is an adaptation to a wireless channel of the dominance protocol used in the CAN bus. But, unlike that protocol, our protocol does not require a node having the ability to receive an incoming bit from the channel while transmitting to the channel. The evaluation of the protocol with real embedded computing platforms is presented to show that the proposed protocol is in fact collision-free and prioritized. We measure the response times of our implementation and show that the response-time analysis developed for the protocol offers an upper bound on the response times.

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Consider the problem of scheduling sporadic message transmission requests with deadlines. For wired channels, this has been achieved successfully using the CAN bus. For wireless channels, researchers have recently proposed a similar solution; a collision-free medium access control (MAC) protocol that implements static-priority scheduling. Unfortunately no implementation has been reported, yet. We implement and evaluate it to find that the implementation indeed is collision-free and prioritized. This allows us to develop schedulability analysis for the implementation. We measure the response times of messages in our implementation and find that our new response-time analysis indeed offers an upper bound on the response times. This enables a new class of wireless real-time systems with timeliness guarantees for sporadic messages and it opens-up a new research area: schedulability analysis for wireless networks.

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Male dominance hierarchies are usually linked to relative body size and to weapon size, that is, to determinants of fighting ability. Secondary sexual characters that are not directly used as weapons could still be linked to dominance if they reveal determination or overall health and vigour and hence, indirectly, fighting ability. We studied the mating behaviour of the minnow, Phoxinus phoxinus, a cyprinid fish in which males develop breeding tubercles during the spawning season. The function of these breeding tubercles is still not clear. Using microsatellite markers, we determined male reproductive success under controlled conditions. The minnows were territorial and quickly established a dominance hierarchy at the beginning of the spawning season. Dominance was strongly and positively linked to fertilization success. Although body size and number of breeding tubercles were not significantly correlated in our sample, both large males and males with many breeding tubercles were more dominant and achieved higher fertilization success than small males or males with few tubercles. We found multimale fertilization in most clutches, suggesting that sperm competition is important in this species. Females showed behaviour that may be linked to spawning decision, that is, male dominance might not be the only determinant of male reproductive success in minnows

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There has been and will continue to be substantial debate over how the international system can best be characterized. The objective of this paper is to demonstrate that the international system can best be characterized by the essential features of realism, but the use of realist policy prescriptions are inadequate when applied independently to deal with the threat of terrorism as it exists today. In order to demonstrate this an examination of realism in the international system, U.S. foreign policy, and case analysis of Afghanistan and Iraq will be undertaken to demonstrate that although realist policy prescriptions do have a role in dealing with modem transnational security threats, these prescriptions on their own are inadequate when dealing with terrorism.

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This paper studies the theoretical and empirical implications of monetary policy making by committee under three different voting protocols. The protocols are a consensus model, where super-majority is required for a policy change; an agenda-setting model, where the chairman controls the agenda; and a simple majority model, where policy is determined by the median member. These protocols give preeminence to different aspects of the actual decision making process and capture the observed heterogeneity in formal procedures across central banks. The models are estimated by Maximum Likehood using interest rate decisions by the committees of five central banks, namely the Bank of Canada, the Bank of England, the European Central Bank, the Swedish Riksbank, and the U.S. Federal Reserve. For all central banks, results indicate that the consensus model is statically superior to the alternative models. This suggests that despite institutionnal differences, committees share unwritten rules and informal procedures that deliver observationally equivalent policy decisions.

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Malgré le fait que le statut social soit reconnu comme ayant une forte influence sur l’aptitude, les facteurs affectant le statut social et les changements de ce statut demeurent peu connus. De plus, les études sur la dominance ayant un lien avec l’agressivité portent rarement sur des femelles. Nous étudierons ces aspects en utilisant Neolamprologus pulcher, un poisson à reproduction coopérative du lac Tanganyika. La probabilité d’ascension sociale était manipulée sur le terrain et les changements physiologiques et comportementaux, ainsi que le niveau plasmatique de testostérone, associé avec l’ascension à la dominance de femelles subordonnées étaient caractérisés. Le degré de coopération et la masse étaient supérieurs chez les femelles ascendantes par rapport aux femelles non-ascendantes d’un même groupe social. Après une semaine d’ascension sociale, les femelles ascendantes ne différaient pas comportementalement, mais différaient physiologiquement des femelles dominantes. Les femelles dominantes, ascendantes et subordonnées ne différaient pas quant au niveau de testostérone plasmatique. Comprendre les bénéfices des comportements coopératifs pour les subordonnés a longtemps posé un problème évolutif. Nos résultats impliquent que les comportements coûteux métaboliquement peuvent avoir été sélectionnés en améliorant l’aptitude future via l’héritage du territoire et du statut social. De plus, le degré de coopération pourrait être un signal de qualité détecté par les compétiteurs et les collaborateurs.