1,720,960 research outputs found
Optimization of flat area coverage under connectivity constraint in wireless sensor networks
No full textUn réseau de capteurs sans fil est constitué d'un ensemble de petites unités autonomes qui interagissent via un réseau construit par leurs modules de communication. Ils observent leur environnement, captent des informations, puis gèrent ces informations en fonction de leur capacité de calcul et/ou de stockage. Pour efficacement accomplir leur(s) tâche(s), ils ont besoin de couvrir autant que possible la zone d'intérêt. Il est donc indispensable de quantifier la qualité de leur couverture. Dans cette thèse, nous cherchons donc à couvrir au mieux une zone d'intérêt, avec un nombre précis de capteurs. Tout en prenant en compte les recouvrement possibles entre capteurs, nous déployons dans un premier temps dans une zone de dimensions régulières et évaluons à l'aide d'un algorithme génétique la couverture exacte. La fonction d'évaluation proposée nous permet de calculer sans biais la couverture exacte des capteurs. Une fois que nous savons couvir et évaluer la couverture d'une zone regulière, la deuxième étape consiste à déployer les capteurs sur une zone de formes irrégulières. L'objectif ici sera d'arriver non seulement à couvrir efficacement la zone en tenant compte des recouvrements des capteurs, mais aussi à privilégier l'intérieur de la zone d'intérêt par rapport à l'extérieur de celle-ci. Nous créons ensuite à l'intérieur de la zone de déploiement, des zones que nous appelons "zones de non intérêt", où les capteurs ne doivent pas être déployés. Enfin, s'il est important d'assurer une bonne couverture d'une zone d'intérêt, il est tout aussi important d'assurer qu'une fois les données captées, celles-ci puissent être envoyées vers les autres les capteurs pour traitement et/ou relais vers le(s) noeud(s) de traitement. Aux objectifs précédement énnoncés, nous ajoutons donc dans le deuxième cas de figure, la contrainte de connectivité totale entre les capteurs.A wireless sensor network consists of a set of small autonomous units that interact via a network built by their communication modules. They observe their environment, capture information, then manage this information according to their computing and/or storage capacity. To effectively accomplish their task(s), they need to cover as much of the area of interest as possible. It is therefore essential to quantify the quality of their coverage. In this thesis, we therefore seek to best cover an area of interest, with a precise number of sensors. While taking into account the possible overlaps between sensors, we first deploy in a zone of regular dimensions and evaluate the exact coverage using a genetic algorithm. The proposed evaluation function allows us to calculate without bias the exact coverage of the sensors. Once we know how to cover and assess the coverage of a regular area, the second step is to deploy the sensors on an area of irregular shapes. The objective here will be to manage not only to effectively cover the zone taking into account the overlapping of the sensors, but also to favor the inside of the zone of interest compared to the outside of it. We then create inside the deployment zone, areas that we call "zones of no interest", where the sensors should not be deployed. Finally, if it is important to ensure good coverage of a area of interest, it is just as important to ensure that once the data has been captured, it can be sent to the other sensors for processing and/or relay to the processing node(s). To the objectives previously stated, we therefore add in the second case, the constraint of total connectivity between the sensors
Optimisation de la couverture d'une zone plane sous la contrainte de connectivité dans les réseaux de capteurs sans fil
No full textA wireless sensor network consists of a set of small autonomous units that interact via a network built by their communication modules. They observe their environment, capture information, then manage this information according to their computing and/or storage capacity. To effectively accomplish their task(s), they need to cover as much of the area of interest as possible. It is therefore essential to quantify the quality of their coverage. In this thesis, we therefore seek to best cover an area of interest, with a precise number of sensors. While taking into account the possible overlaps between sensors, we first deploy in a zone of regular dimensions and evaluate the exact coverage using a genetic algorithm. The proposed evaluation function allows us to calculate without bias the exact coverage of the sensors. Once we know how to cover and assess the coverage of a regular area, the second step is to deploy the sensors on an area of irregular shapes. The objective here will be to manage not only to effectively cover the zone taking into account the overlapping of the sensors, but also to favor the inside of the zone of interest compared to the outside of it. We then create inside the deployment zone, areas that we call "zones of no interest", where the sensors should not be deployed. Finally, if it is important to ensure good coverage of a area of interest, it is just as important to ensure that once the data has been captured, it can be sent to the other sensors for processing and/or relay to the processing node(s). To the objectives previously stated, we therefore add in the second case, the constraint of total connectivity between the sensors.Un réseau de capteurs sans fil est constitué d'un ensemble de petites unités autonomes qui interagissent via un réseau construit par leurs modules de communication. Ils observent leur environnement, captent des informations, puis gèrent ces informations en fonction de leur capacité de calcul et/ou de stockage. Pour efficacement accomplir leur(s) tâche(s), ils ont besoin de couvrir autant que possible la zone d'intérêt. Il est donc indispensable de quantifier la qualité de leur couverture. Dans cette thèse, nous cherchons donc à couvrir au mieux une zone d'intérêt, avec un nombre précis de capteurs. Tout en prenant en compte les recouvrement possibles entre capteurs, nous déployons dans un premier temps dans une zone de dimensions régulières et évaluons à l'aide d'un algorithme génétique la couverture exacte. La fonction d'évaluation proposée nous permet de calculer sans biais la couverture exacte des capteurs. Une fois que nous savons couvir et évaluer la couverture d'une zone regulière, la deuxième étape consiste à déployer les capteurs sur une zone de formes irrégulières. L'objectif ici sera d'arriver non seulement à couvrir efficacement la zone en tenant compte des recouvrements des capteurs, mais aussi à privilégier l'intérieur de la zone d'intérêt par rapport à l'extérieur de celle-ci. Nous créons ensuite à l'intérieur de la zone de déploiement, des zones que nous appelons "zones de non intérêt", où les capteurs ne doivent pas être déployés. Enfin, s'il est important d'assurer une bonne couverture d'une zone d'intérêt, il est tout aussi important d'assurer qu'une fois les données captées, celles-ci puissent être envoyées vers les autres les capteurs pour traitement et/ou relais vers le(s) noeud(s) de traitement. Aux objectifs précédement énnoncés, nous ajoutons donc dans le deuxième cas de figure, la contrainte de connectivité totale entre les capteurs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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