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Stimulus-Free RT Level Power Model using Belief PropagationPonraj, Sathishkumar 25 October 2004 (has links)
Power consumption is one of the major bottlenecks in current and future VLSI design. Early microprocessors, which consumed a few tens of watts, are now replaced by millions of transistors and with the introduction of easy-to-design tools to explore at unbelievable minimum dimensions, increase in chip density is increasing at a alarming rate and necessitates faster power estimation methods. Gate level power estimation techniques are highly accurate methods but when time is the main constraint, power has to be estimated a lot higher in the abstraction level. Estimating power at higher levels also saves valuable time and cost involved in redesigning when design specifications are not met. We estimate power at every levels of abstraction for a breadth first design-space exploration. This work targets a stimulus-free pattern-insensitive RT level hierarchical probabilistic model, called Behavioral Induced Directed Acyclic Graph (BIDAG), that can freely traverse between the RT and logic level and we prove that such a model corresponds to a Bayesian Network to map all the dependencies and can be used to model the joint probability distribution of a set of variables. Each node or variable in this structure represents a gate level Directed Acyclic Graph structure, called the Logic Induced Directed Acyclic Graph (LIDAG). We employ Bayesian networks for the exact representation of underlying probabilistic framework at RT level, capturing the dependence exactly and again use the same probabilistic model for the logic level. Bayesian networks are graphical representations used to concisely represent the uncertain knowledge of the system. In order to get an posterior belief of a query node or variable, with or without preset nodes or variables called the evidence nodes, we use stochastic inference algorithm, based on importance sampling method, called the Evidence Pre-propagation Importance Sampling (EPIS) which is anytime and scales really well for RT and logic networks. Experimental results indicate that this method of estimation yields high accuracy and is qualitatively superior to macro-models under a wider range of input patterns. The main highlights of this work is that as it is a probabilistic model, it is input pattern independent and nonsimulative property implies less time for power modelling.
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Addressing the contradiction between discourse and practice in health promotion.Laverack, Glenn, kimg@deakin.edu.au,jillj@deakin.edu.au,mikewood@deakin.edu.au,wildol@deakin.edu.au January 1999 (has links)
The main theme of this thesis is the contradiction between discourse and practice in health promotion. Many health promoters continue to exert power-over the community through top-down programming whilst at the same time using an emancipatory discourse. The thesis has addressed this contradiction in three parts. The first part determines how the emancipatroty discourse has evolved and eplores the role of social movements in the development of contemporary health discourses and their influence on the legitimisation of empowerment. Central to this discourse is the empowerment of communities. To understand the role of this concept the thesis provides an interpretation of the different meanings of power and community, and the different levels of analysis of empowerment in the context of health promotion programming.
The second part identifies the nature of health programming and the dominance of top-down, and to a much lesser extent, bottom-up approaches. The thesis argues that these two approaches are not, and do not have to be, mutually exclusive. To address this issue the thesis presents a new methodology is situated within a framework developed for the accomodation of empowerment goals within health promotion programmes. The study also identifies the organisational areas of influence on the processs of community empowerment and it is these which are used for the assessment of this concept. Both the framework and the methodology address the contradiction in health promotion by making community empowerment operational within a programme context.
The third part of the thesis supports the rationale for the design of the methodology with field work in rural Fijian communities. The findings are presented as a composite case study to highlight the experiences of implementing the methodolgy and the main themes that emerged during the field work. the final chapter of the thesis brings together the central themes of the study and draws from these and 'emergent agenda' as a way forward for health promotion research and practice.
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Changement technique et double dividende d'écotaxes. Un essai sur la confluence des prospectives énergétique et macro-économiqueGHERSI, Frédéric 01 April 2003 (has links) (PDF)
Les travaux présentés dans cette thèse portent sur l'évaluation des coûts macro-économiques de politiques climatiques nationales et mondiales.<br />Ils reposent sur une mise en relation innovante des prospectives énergétique et macroéconomique, dont l'objectif est d'assurer la représentation fidèle, dans la modélisation macroéconomique, des élasticités du système énergétique mises en lumière par l'analyse technico-économique.<br />Ils opèrent aussi un questionnement critique des études analytiques ayant conclu à l'improbabilité d'un dividende économique net de réformes fiscales environnementales, en démontrant que le signe ultime de l'effet prix général d'une réforme « écofiscale » est dépendant des structures de production et de consommation préexistant à la réforme, ainsi que de leur réactivité au signal-prix.<br />Ils soulignent enfin le rôle prépondérant du changement technique induit et de ses modalités—éviction de l'investissement de productivité générale éventuellement corrigée par une diffusion du progrès technique spécifique—sur l'obtention d'un second dividende.
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Age differences in arousal, perception of affective pictures, and emotional memory enhancement : Appraisal, Electrodermal activity, and Imaging dataGavazzeni, Joachim January 2008 (has links)
<p>In contrast to effortful cognitive functions, emotional functioning may remain stable or even be enhanced in older adults. It is unclear how affective functions in aging correspond to subjective experiences and physiological changes. In <b>Study I</b>, ratings of emotional intensity and neural activity to facial expressions using functional magnetic resonance imaging (fMRI) were analyzed in younger and older adults. Negative expressions resulted in increased neural activity in the right amygdala and hippocampus in younger adults, and increased activation in the right insular cortex in older adults. There were no age differences in subjective ratings. In <b>Study II</b>, subjective ratings of, and skin conductance response (SCR) to, neutral and negative pictures were studied. The ratings of negative pictures were higher for older adults compared to younger adults. SCRs increased in both age groups for the negative pictures, but magnitude of SCRs was significantly larger in younger adults. Finally, in <b>Study III</b>, emotional memory after a one-year retention interval was tested. The memory performance of both age groups was higher in response to negative pictures compared to neutral ones, although the performance was generally higher for younger adults. SCR at encoding was the better arousal predictor for memory, but only in younger adults. The results indicate age-related changes in affective processing. Age differences may involve a gradual shift from bottom-up processes, to more top-down processes. The results are discussed in a wider lifespan perspective taking into consideration the accumulated life experience of older adults.</p>
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Formalisation of edit operations for structure editorsHolmquist, Johan January 2005 (has links)
<p>Although several systems with structure editors have been built, no model exist to formally describe the edit operations used in such editors. This thesis introduces such a model --- a formalism to describe general structure edit operations for text oriented documents. The model allows free bottom-up editing for any tree-based structural document with a textual content. It can also handle attribute and erroneous structures. Some classes of common structures have been identified and structure editor specifications constructed for them, which can be used and combined in the creation of other structure editors.</p>
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Age differences in arousal, perception of affective pictures, and emotional memory enhancement : Appraisal, Electrodermal activity, and Imaging dataGavazzeni, Joachim January 2008 (has links)
In contrast to effortful cognitive functions, emotional functioning may remain stable or even be enhanced in older adults. It is unclear how affective functions in aging correspond to subjective experiences and physiological changes. In Study I, ratings of emotional intensity and neural activity to facial expressions using functional magnetic resonance imaging (fMRI) were analyzed in younger and older adults. Negative expressions resulted in increased neural activity in the right amygdala and hippocampus in younger adults, and increased activation in the right insular cortex in older adults. There were no age differences in subjective ratings. In Study II, subjective ratings of, and skin conductance response (SCR) to, neutral and negative pictures were studied. The ratings of negative pictures were higher for older adults compared to younger adults. SCRs increased in both age groups for the negative pictures, but magnitude of SCRs was significantly larger in younger adults. Finally, in Study III, emotional memory after a one-year retention interval was tested. The memory performance of both age groups was higher in response to negative pictures compared to neutral ones, although the performance was generally higher for younger adults. SCR at encoding was the better arousal predictor for memory, but only in younger adults. The results indicate age-related changes in affective processing. Age differences may involve a gradual shift from bottom-up processes, to more top-down processes. The results are discussed in a wider lifespan perspective taking into consideration the accumulated life experience of older adults.
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Impacts Of Nutrients On Periphyton Growth And Periphyton-macroinvertebrates Interactions In Shallow Lakes: A Mesocosm ExperimentFiliz, Nur 01 October 2012 (has links) (PDF)
Periphyton biomass on artificial strips was observed monthly to see the impacts of nutrient differences on periphyton and periphyton-macroinvertebrates interaction. The experiment was conducted for four months in a mesocosm which were runned at six countries at the same time and with the same steps. Eight enclosures at two meters depth were used that four of them had high nutrient level and the other four had low nutrient level. Sediment, macrophyte, fish, plankton, benthic invertebrates and water were added at the same time and with the same way in all of the countries. Periphyton growth which formed on artificial 32 cm2 strips for June, July, August and September were brushed to filtered mesocosm water and dry mass, ash free dry mass, phosphorus content and chlorophyl-a concentrations were measured. Grazer pressure on the periphyton was observed with a laboratory experiment for July, August and September months. At the end of the mesocosm experiment macrophytes and fish were harvested. Macrophytes&rsquo / dry mass and fish&rsquo / abundance were measured. Moreover at the end of the experiment epiphyton was also measured. Three kajak cores were taken from sediment for macroinvertebrates at the end of the experiment and identified. All physical features of mesocosm enclosures and PVI data were recorded for every 2 weeks.
Periphyton biomass was higher concentrations in HN enclosures than LN tanks. Only dry mass of periphyton biomass showed the opposite because of the marl deposition in LN tanks. This finding was also reinforced by epiphyton samples which was taken at the end of the experiment. LN enclosures had the more abundance of macroinvertebrate. The groups we found in sediment which had big grazer effect on periphyton such as gastropods and Chironomidae. Grazer experiment showed that grazer effect on periphyton increased in time. Although this raise, periphyton growth also increased in LN enclosures with nutrient increasing. This may be indicate that nutrient effect has a stronger effect than grazer pressure on periphyton.
As it is explained before in the beginning of the experiment all of the conditions were the same except nutrient level. Thus, bottom-up effect changed the top-down control and at the end of the experiment we saw the more periphyton less macroinvertebrate and more fish in HN tanks while the opposite was seen in LN tanks.
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Electrophysiological Events Related to Top-down Contrast Sensitivity ControlMisic, Bratislav 14 July 2009 (has links)
Stimulus-driven changes in the gain of sensory neurons are well-documented, but relatively little is known about whether analogous gain-control can also be effected in a top-down manner. A recent psychophysical study demonstrated that sensitivity to luminance contrast can be modulated by a priori knowledge (de la Rosa et al., in press). In the present study, event-related potentials were used to resolve the stages of information processing that facilitate such knowledge-driven adjustments. Groupwise independent component analysis identified two robust spatiotemporal patterns of endogenous brain activity that captured experimental effects. The first pattern was associated with obligatory processing of contextual information, while the second pattern
was associated with selective initiation of contrast gain adjustment. These data suggest
that knowledge-driven contrast gain control is mediated by multiple independent electrogenic sources.
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Écologie fonctionnelle dans les nappes phréatiques : liens entre flux de matière organique, activité et diversité biologiquesFoulquier, Arnaud 22 September 2009 (has links) (PDF)
Les réseaux trophiques jouent un rôle primordial dans la régulation des flux de matière et d'énergie au sein des écosystèmes. Dans le cadre des pratiques de recharge artificielle des aquifères, les biocénoses souterraines sont pleinement sollicitées et leur capacité à dégrader les flux de matière organique de surface conditionne le maintien de la qualité des eaux souterraines. L'objectif de ce travail est de déterminer l'influence d'une augmentation des flux de carbone organique dissous sur l'intensité des interactions trophiques entre les communautés microbiennes et les assemblages d'invertébrés au toit des nappes phréatiques rechargées artificiellement avec des eaux de ruissellement pluvial. A travers une approche expérimentale de terrain et de laboratoire, ce travail permet d'évaluer l'intensité des relations existant entre les flux de carbone organique dissous, les conditions environnementales, l'activité et la diversité de communautés microbiennes et l'abondance des communautés d'invertébrés.
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Electrophysiological Events Related to Top-down Contrast Sensitivity ControlMisic, Bratislav 14 July 2009 (has links)
Stimulus-driven changes in the gain of sensory neurons are well-documented, but relatively little is known about whether analogous gain-control can also be effected in a top-down manner. A recent psychophysical study demonstrated that sensitivity to luminance contrast can be modulated by a priori knowledge (de la Rosa et al., in press). In the present study, event-related potentials were used to resolve the stages of information processing that facilitate such knowledge-driven adjustments. Groupwise independent component analysis identified two robust spatiotemporal patterns of endogenous brain activity that captured experimental effects. The first pattern was associated with obligatory processing of contextual information, while the second pattern
was associated with selective initiation of contrast gain adjustment. These data suggest
that knowledge-driven contrast gain control is mediated by multiple independent electrogenic sources.
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