467 research outputs found
Recueil dâinformations et identifications des principaux enjeux et des moyens de mise en Ćuvre
TirĂ© de l'Ă©cran-titre (visionnĂ© le 27 juin 2017).Face Ă lâĂ©mergence de fĂ©dĂ©rations dâidentitĂ© dans le domaine de lâĂ©ducation dans plusieurs pays du monde, le GTN-QuĂ©bec sâĂ©tait donnĂ© le mandat de dĂ©finir le concept de la fĂ©dĂ©ration de lâidentitĂ© dans le milieu scolaire quĂ©bĂ©cois. Lâobjectif de cet article Ă©tait de fournir les informations pertinentes et nĂ©cessaires aux organismes de lâĂ©ducation face Ă lâĂ©mergence dâune fĂ©dĂ©ration dâidentitĂ©. [...
From the Olive Flower to the Drupe: Flower Types, Pollination, Self and Inter-Compatibility and Fruit Set
Automotive technology & trade
Carta a los médicos jefe de los asilos de locos «Lettre aux médecins-chefs des asiles de fous», (1925).
TraducciĂłn de Ăngel Cagiga
Molar and Molecular Models of Performance for Rewarding Brain Stimulation
This dissertation reports analyses of performance for rewarding brain stimu- lation in a three-part sequential task. A session of self-stimulation was composed of three trial types, during which the strength and opportunity cost of electrical stim- ulation were kept constant. Within a trial, a lever allowed animals to harvest brain stimulation rewards as soon as the lever had been held for a set, cumulative amount of time. When the time spent holding reached this criterion, the lever retracted and a burst of rewarding electrical stimulation was delivered. A flashing house light and 10s inter-trial interval signalled the start of a new trial. Rats were presented with strong/inexpensive/certain stimulation on one trial, a randomly selected strength, cost and risk on the next trial, and weak/inexpensive/certain stimulation on the third trial of a sequence. The sequence then repeated. Rewards during the second trial of this sequence were delivered with cued probabilities ranging from 0.5 to 1.0. The current thesis evaluates the ability of a previously published (molar) model of performance during a trial to accurately detect the effect of risk on payoff but not reward intensity. Although animals were less willing to work for stimulation trains that may not be delivered than those delivered with certainty, risk did not change the relative reward produced by stimulation. We also present evidence on a fine time scale that self-stimulating rats develop a model of their world. The first pause made as a trial began was a function of the payoff the animal had yet to receive, indicat- ing that rats had a model of the triad sequence. Analysis of the conditions under which pauses were uncharacteristic also provides evidence of what this model might be. Analysis of the fine scale of performance provides evidence that animals had a model of the stability of trial conditions. Finally, we present a (molecular) model of performance for brain stimulation rewards in real-time. Our results demonstrate that rats develop a model of the testing paradigm and can adjust to changes in reward contingencies with as few as one exemplar
Développement d'un systÚme de surveillance des mécanismes de qualité de service dans le contexte des réseaux de prochaine génération
Afin de faciliter la configuration et la surveillance des mĂ©canismes de qualitĂ© de service mis en place dans un rĂ©seau, un outil appropriĂ© doit ĂȘtre mis Ă la disposition des administrateurs rĂ©seau. Cet outil doit permettre une visualisation des configurations et une visualisation de statistiques relatives Ă la qualitĂ© de service. Un tel outil permet, par consĂ©quent, de valider l'homogĂ©nĂ©itĂ© des configurations Ă travers l'ensemble du rĂ©seau de l'administrateur en plus d'identifier les sources de dĂ©gradation de la qualitĂ© de service.
En plus de définir la place que peut occuper cet outil dans le contexte des réseaux de prochaine génération (NGN), ce document présente le développement d'une architecture de base permettant la visualisation des mécanismes de qualité de service dans un réseau hétérogÚne. Il décrit, entre autre, les diverses composantes de l'architecture ainsi que le développement de chacune d'elles.
Ce dĂ©veloppement, rĂ©alisĂ© au Laboratoire de gestion de rĂ©seaux informatiques et de tĂ©lĂ©communications (LAGRIT), a Ă©tĂ© validĂ© par une sĂ©rie d'essais rĂ©alisĂ©s dans les laboratoires de Bell Canada. Ce projet est donc considĂ©rĂ© comme un projet industriel puisqu'il a abouti Ă un produit pouvant ĂȘtre utilisĂ© par un administrateur de rĂ©seau.
Finalement, certaines suggestions ont Ă©tĂ© apportĂ©es afin de permettre, dans un premier temps, d'amĂ©liorer les performances du systĂšme et dans un deuxiĂšme temps, de dĂ©velopper d'autres fonctionnalitĂ©s pouvant ĂȘtre implĂ©mentĂ©es dans un contexte de recherche future
An Aerial Survey Technique for the Forest-Dwelling Ecotype of Woodland Caribou, Rangifer tarandus caribou
Accurate and precise population estimates for the forest-dwelling ecotype of Woodland Caribou (Rangifer tarandus caribou) are very difficult to obtain because these Caribou are found at very low densities and in small herds dispersed over large areas. In order to suggest a standardized method, data from aerial surveys conducted in 1991 and 1993 (12 000 km2 blocks) were used to simulate various survey scenarios. Simulations showed that all the major groups of Caribou would have to be found and counted to obtain a confidence interval of ± 20% (α = 0.10). We tested this technique in a survey carried out in winter 1999 in a 42 539 km2 study site, opting for a total coverage carried out in two phases. In phase one, we used an airplane, flying north-south transects spaced 2.1 km apart so as to detect most Caribou track networks. In phase two, a helicopter was used to count and determine the sex and age classes (calves/adults) of Caribou found in phase one. Using 20 radio-collared Caribou, the visibility rate of Caribou groups (phase one) and that of Caribou within the groups (phase two) were estimated at 0.90 and 0.94 respectively for an overall rate of 0.85 (SE = 0.08; α = 0.10). The corrected density was estimated at 1.6 Caribou per 100 km2 with a 15% confidence interval (α = 0.10). The survey cost approximately 7/km2). Two main factors contributed to diminish costs: (1) the use of long-range airplanes (5-7 hours flying range) in phase one to minimize travel between the airports and the study site, and (2) the use of helicopters only in phase two for counting and determining the age and sex of the Caribou.Il est trĂšs difficile dâobtenir des estimations de population exactes et prĂ©cises pour lâĂ©cotype forestier du Caribou des bois (Rangifer tarandus caribou) parce quâon le retrouve en trĂšs faibles densitĂ©s et quâil est distribuĂ© en petites hardes rĂ©parties sur de vastes superficies. Les rĂ©sultats de deux inventaires aĂ©riens rĂ©alisĂ©s en 1991 et 1993 (12 000 km2) ont Ă©tĂ© utilisĂ©s pour simuler divers scĂ©narios dâinventaire afin de suggĂ©rer une mĂ©thode standardisĂ©e. Les simulations ont montrĂ© quâil fallait trouver et recenser tous les groupes principaux pour obtenir un intervalle de confiance de ± 20 % (α = 0,10). Nous avons testĂ© cette approche dans un site dâĂ©tude de 42 539 km2 oĂč nous avons optĂ© pour un plan en deux phases. En phase un, lâavion a Ă©tĂ© utilisĂ© pour couvrir totalement le site dâĂ©tude selon des virĂ©es Ă©quidistantes de 2,1 km afin de dĂ©tecter la plupart des rĂ©seaux de pistes. LâhĂ©licoptĂšre fut utilisĂ© en phase deux pour dĂ©nombrer et sexer les Caribous dans les rĂ©seaux de pistes dĂ©tectĂ©s en phase un. DâaprĂšs 20 Caribous munis de colliers Ă©metteurs, le taux de visibilitĂ© global Ă©tait de 0,85 (SE = 0,08; α = 0,10), soit 0,90 en phase 1 et 0,94 en phase 2. La densitĂ© corrigĂ©e Ă©tait de 1,6 Caribou par 100 km2 avec une erreur relative de 15 % (α = 0,10). Lâinventaire a coĂ»tĂ© 4 /km2). La diminution des coĂ»ts est attribuable Ă deux facteurs principaux : (1) lâutilisation dâavions Ă grand rayon dâaction (5-7 heures dâautonomie) pour minimiser les dĂ©placements en phase un; (2) lâemploi dâhĂ©licoptĂšres exclusivement pour le dĂ©nombrement et le sexage des caribous
Historical Changes and Current Distribution of Caribou, Rangifer tarandus, in Quebec
We examined published historical information, reports on aerial surveys conducted since 1953, and harvest data collected since 1971 to describe changes in the distribution and abundance of Caribou (Rangifer tarandus) in QuĂ©bec. The southern limit of the Caribou distribution diminished considerably in the late 19th century, and the decline in numbers probably continued until the 1960s and 1970s east of the 62nd meridian. South of the 49th parallel, only four small populations still persist. Despite the fact that all Caribou of the province were assigned to the same sub-species (R. t. caribou), three ecotypes with specific habitats and behaviour are found. The Barren-Ground ecotype, the only migratory form, is found north of the 52nd parallel. This ecotype currently occupies â 255 000 km2 in fall and winter, mainly in the ecological subzones of the forest tundra and the taiga. The Barren-Ground Caribou was characterized by a very low abundance from the end of the 19th century until the mid-1950s, but increased markedly thereafter reaching over a million individuals at the beginning of the 1990s. Populations of the Mountain ecotype have been identified in the southeastern and, possibly, in the northeastern parts of the province. The latter Mountain population is virtually unknown. The southeastern population is sedentary and uses mainly the boreal forest. This population has decreased over the last century and currently numbers only â 140 individuals. Finally, the Forest-Dwelling ecotype is found discontinuously, mainly between the 49th and 55th parallels. Its current distribution covers â 235 000 km2, mainly east of the 72nd meridian. This sedentary ecotype is found almost exclusively in the boreal forest, principally in areas with long forest fire cycles. Its abundance has also decreased over the years. Large Forest-Dwelling populations still persisted during the 1950s and 1960s, but they apparently disappeared. The current abundance is not known precisely, but based on density estimates and considering the current distribution, it probably does not exceed 3000 individuals. Current data are insufficient to identify precisely the causes of the population decline, although hunting seems to be an important proximal cause.Nous avons utilisĂ© les donnĂ©es historiques publiĂ©es, les rapports dâinventaires aĂ©riens rĂ©alisĂ©s depuis 1953 et les statistiques de rĂ©colte sportive colligĂ©es depuis 1971 pour dĂ©crire les changements dans la rĂ©partition et lâabondance du Caribou (Rangifer tarandus) au QuĂ©bec. La limite mĂ©ridionale de lâaire de rĂ©partition a beaucoup diminuĂ© Ă la fin du 19e siĂšcle et la rĂ©gression sâest probablement poursuivie durant les annĂ©es 1960 et 1970 Ă lâest du 62e mĂ©ridien. Au sud du 49e parallĂšle, on ne retrouve plus que quatre petites populations. Bien que tous les caribous du QuĂ©bec soient considĂ©rĂ©s appartenir Ă la mĂȘme sous-espĂšce (R. t. caribou), on distingue trois Ă©cotypes frĂ©quentant des milieux diffĂ©rents et arborant des comportements spĂ©cifiques. Au nord du 52e parallĂšle, on retrouve lâĂ©cotype Toundrique, lequel est migrateur. Ces Caribous se rĂ©partissent sur â 255 000 km2 durant lâautomne et lâhiver, principalement dans les sous-zones Ă©cologiques de la toundra forestiĂšre et de la taĂŻga. Cet Ă©cotype Ă©tait peu abondant entre la fin du 19e siĂšcle et le milieu des annĂ©es 1950, mais il sâest accru considĂ©rablement pour atteindre plus dâun million dâindividus au dĂ©but des annĂ©es 1990. Une population de lâĂ©cotype Montagnard est prĂ©sente au sud-est de la province et une autre existe possiblement au nord-est. Cette derniĂšre nâest pas bien connue. Celle du sud-est utilise principalement la forĂȘt borĂ©ale. Cette population sĂ©dentaire a diminuĂ© considĂ©rablement depuis une centaine dâannĂ©es et elle ne compte plus quâenviron 140 individus. Finalement, lâĂ©cotype Forestier est prĂ©sent de façon discontinue, principalement entre les 49e et 55e parallĂšles. Ces Caribous sont Ă©galement sĂ©dentaires. On les retrouve presque exclusivement en forĂȘt borĂ©ale, principalement lĂ oĂč le cycle des feux de forĂȘt est long. Leur rĂ©partition actuelle couvre â 234 000 km2, principalement Ă lâest du 72e mĂ©ridien. Dâimportantes populations forestiĂšres existaient encore durant les annĂ©es 1950 et 1960, mais elles semblent avoir disparu. Lâabondance actuelle nâest pas connue mais elle pourrait difficilement dĂ©passer 3000 individus si lâon se base sur les estimations de la densitĂ© et de lâaire de rĂ©partition. Les donnĂ©es disponibles sont insuffisantes pour identifier les causes exactes des diminutions dâeffectifs bien que la chasse semble une cause proximale importante
Book Review: True West: Authenticity and the American West
In the culture of the American West, the term authenticity comes close to frontier in its ubiquity, resonance, and elusiveness. The fifteen essays in this outstanding collection clarify how authenticity has functioned in cultural and literary settings. Instead of simply distinguishing the fake from the authentic, they explore the nature and consequences of quests for and claims to authenticity. Readers interested in the Great Plains will find rewarding essays on literature, environment, and the uses of American Indian history
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