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Advancing Traffic Safety : An evaluation of speed limits, vehicle-bicycle interactions, and I2V systemsPezo Silvano, Ary January 2016 (has links)
Since the introduction of motor vehicles, the number of fatalities and accidents has been a concern for society.The number of fatalities on roads is amongst the most common causes of mortality worldwide (WHO, 2015).Even in industrialized countries the number of fatalities remains unacceptable. Therefore, in the last decades, anumber of approaches have emerged to support and boost traffic safety towards a system free from fatalities andserious impairment outcomes. ‘Sustainable Safety’ and ‘Vision Zero’ are well-known examples aiming to avoidfatalities within the traffic system and reduce injury severity when a traffic accident is inevitable. However, thenumber of fatalities and seriously injured accidents are still relatively high. More specifically, vulnerable roadusers remain involved in fatal and serious accidents even in industrialized countries. Therefore, further advancesin traffic safety studies are needed. This thesis aims at evaluating the impact of road characteristics, traffic rulesand information provision towards a safer traffic system. The thesis is composed of five scientific papers whichsummarizes the main contributions of this work. / <p>QC 20161109</p>
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Till alla som inte tränar , för att få en vacker och hälsosam kropp så krävs blod, svett och tårar. (Blogg 1) : - En kvalitativ studie om hur hälsosam livsstil framställs och vilka hälsobudskap som förmedlas i bloggar.Marton, Sandra, Iordache, Sorina January 2016 (has links)
Denna studie utgår från socialkonstruktivism som belyser sociala beteenden, som är konstruerade och där individer skapar mening genom att samspela med varandra. Datorer, Internet och Digitala medier tar en alltmer större plats i barn och ungdomars liv då de växer upp i en alltmer digitaliserad värld till skillnad från tidigare generationer. Syftet med studien är att utifrån socialkonstruktivism belysa hur hälsobudskap framträder i hälsobloggar kring lärande om hälsa. Frågeställningar: Hur framställs hälsobudskapen kring kropp, träning och kost som skrivs av unga killar respektive tjejer? Vilka hälsoråd ger bloggarna till läsarna?Teorier som användes i studien är socialkonstruktivism, sociokulturellt perspektiv, praktikgemenskap samt Hälsism Metod som används i denna studie är netnografi och konventionell innehållsanalys. Netnografi användes för att observera dagliga bloggars uppdateringar under en tre veckors period medan konventionell kvalitativ innehållsanalys användes för att bearbeta insamlad dataempiri. Resultatet i studien visar att bloggars hälsobudskap handlar om att se en vältränad kropp som ett mål, dvs. ett kvitto för hälsa där både kroppens utseende och funktion är viktiga i förmedlingen i att uppnå hälsa. Hälsoråd om träning ges i olika variationer genom hänvisningar till olika digitala verktyg och detta för att öka kunskap bland läsare. Samtidigt handlar dessa råd om att kost handlar ofta om att äta nyttigt, dvs. vara vegetarian eller vegan. / This study is based on social constructivism that highlights socially constructed behaviors where individuals create meaning by interacting with each other. Computers, Internet and Digital media all overshadows a great part of children and young people's lives, because they are growing up in a more and more increasingly digitized world, unlike previous generations.The purpose of the study from a social constructivism perspective is to illustrate how health messages appear in health blogs from a gender perspective. Questions: How is health messages rendered out regarding body, exercise and diet written by young boys and girls? What type of health advice is shared by the bloggers? Theories used in the study is social constructivism, social perspectives, communities of practice and Healthism. Methods used in this study is cyber-ethnography and conventional content analysis. Cyber-ethnography was used to observe the daily blog updates over a three week period while the conventional qualitative content analysis was used to process the collected empirical data. The results of the study show that the health messages from blogs displays the body as a goal, ie, a form of receipt for health where both body appearance and function are important factors in the process of achieving health. Health advice on training is given in different variations by referring to various digital tools in order to increase knowledge among readers. At the same time the advice concerns dieting, it shows that eating healthy also/often means being a vegetarian or vegan.
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Decentralized network control, optimization and random walks on networks / Contrôle de réseau décentralisé, optimisation et marches aléatoires sur réseauxDe Bacco, Caterina 08 September 2015 (has links)
Dans les dernières années, plusieurs problèmes ont été étudiés à l'interface entre la physique statistique et l'informatique. La raison étant que, souvent, ces problèmes peuvent être réinterprétés dans le langage de la physique des systèmes désordonnés, où un grand nombre de variables interagit à travers champs locales qui dépendent de l'état du quartier environnant. Parmi les nombreuses applications de l'optimisation combinatoire le routage optimal sur les réseaux de communication est l'objet de la première partie de la thèse. Nous allons exploiter la méthode de la cavité pour formuler des algorithmes efficaces de type ‘’message-passing’’ et donc résoudre plusieurs variantes du problème grâce à sa mise en œuvre numérique. Dans un deuxième temps, nous allons décrire un modèle pour approcher la version dynamique de la méthode de la cavité, ce qui permet de diminuer la complexité du problème de l'exponentielle de polynôme dans le temps. Ceci sera obtenu en utilisant le formalisme de ‘’Matrix Product State’’ de la mécanique quantique.Un autre sujet qui a suscité beaucoup d'intérêt en physique statistique de processus dynamiques est la marche aléatoire sur les réseaux. La théorie a été développée depuis de nombreuses années dans le cas que la topologie dessous est un réseau de dimension d. Au contraire le cas des réseaux aléatoires a été abordé que dans la dernière décennie, laissant de nombreuses questions encore ouvertes pour obtenir des réponses. Démêler plusieurs aspects de ce thème fera l'objet de la deuxième partie de la thèse. En particulier, nous allons étudier le nombre moyen de sites distincts visités au cours d'une marche aléatoire et caractériser son comportement en fonction de la topologie du graphe. Enfin, nous allons aborder les événements rares statistiques associées aux marches aléatoires sur les réseaux en utilisant le ‘’Large deviations formalism’’. Deux types de transitions de phase dynamiques vont se poser à partir de simulations numériques. Nous allons conclure décrivant les principaux résultats d'une œuvre indépendante développée dans le cadre de la physique hors de l'équilibre. Un système résoluble en deux particules browniens entouré par un bain thermique sera étudiée fournissant des détails sur une interaction à médiation par du bain résultant de la présence du bain. / In the last years several problems been studied at the interface between statistical physics and computer science. The reason being that often these problems can be reinterpreted in the language of physics of disordered systems, where a big number of variables interacts through local fields dependent on the state of the surrounding neighborhood. Among the numerous applications of combinatorial optimisation the optimal routing on communication networks is the subject of the first part of the thesis. We will exploit the cavity method to formulate efficient algorithms of type message-passing and thus solve several variants of the problem through its numerical implementation. At a second stage, we will describe a model to approximate the dynamic version of the cavity method, which allows to decrease the complexity of the problem from exponential to polynomial in time. This will be obtained by using the Matrix Product State formalism of quantum mechanics. Another topic that has attracted much interest in statistical physics of dynamic processes is the random walk on networks. The theory has been developed since many years in the case the underneath topology is a d-dimensional lattice. On the contrary the case of random networks has been tackled only in the past decade, leaving many questions still open for answers. Unravelling several aspects of this topic will be the subject of the second part of the thesis. In particular we will study the average number of distinct sites visited during a random walk and characterize its behaviour as a function of the graph topology. Finally, we will address the rare events statistics associated to random walks on networks by using the large-deviations formalism. Two types of dynamic phase transitions will arise from numerical simulations, unveiling important aspects of these problems. We will conclude outlining the main results of an independent work developed in the context of out-of-equilibrium physics. A solvable system made of two Brownian particles surrounded by a thermal bath will be studied providing details about a bath-mediated interaction arising for the presence of the bath.
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Influence of predator and food chemical cues in the behaviour of the house mouse (Mus musculus) / Influence des signaux chimiques des prédateurs et la nourriture sur le comportement de la souris domestique (Mus musculus)Grau Paricio, Carlos 11 January 2019 (has links)
Les rongeurs commensaux sont responsables de grands dommages en agriculture et dans les zones urbaines. En tant qu’espèces invasives, elles peuvent mettre en danger les espèces locales et sont porteurs et vecteurs de plusieurs zoonoses importantes. Les méthodes de contrôle sont basées principalement sur l’utilisation des warfarines, lesquelles produisent un grand nombre d’intoxications sur des espèces non ciblées et ont perdu une partie de leur efficacité à cause des résistances génétiques constatées chez les espèces cibles. De plus, ces méthodes sont considérées comme inhumaines parce qu’elles causent une mort lente et douloureuse par hémorragies. L’olfaction est une source principale d’évaluation des risques présents dans l’environnement pour les rongeurs, avec la perception des signaux chimiques des prédateurs ou signaux de toxicité des plants/nourriture. Cette perception olfactive peut être utilisé pour modifier l’utilisation de l’espace des rongeurs. L’objectif de cette thèse était l’identification des réponses comportementales aux messages chimiques importants (par exemple les signaux chimiques émis par les plantes et les prédateurs) dans l’écologie de la souris domestique (Mus musculus), avec l’utilisation de souches de laboratoire comme modèle des animaux sauvages. Nos résultats ont montré que la souris a évité de façon significative les signaux chimiques complexes du furet et un signal chimique ubiquitaire des plantes, lié à la maturation et la pourriture des aliments (l’éthanol). La protéine du chat Fel d 1, laquelle fait partie de la famille des sécrotoglobines et est un allergène majeur du chat, n’a pas modifié le comportement d’exploration de la souris ou son comportement de recherche et de consommation de nourriture. Le composant chimique des fèces de renard, le TMT a induit un évitement clair et des réponses de stress comme cela a été rapporté dans la littérature. De plus, j’ai fait une revue de la littérature pour évaluer et discuter les méthodes de contrôle des rongeurs d’un point de vue éthique, revue qui a démontré que les méthodes actuelles peuvent être considérés inhumaines et ne correspondent pas aux attentes actuelles de la société et aux standards sur le bien-être dans d’autres domaines comme les élevages de production ou les animaux de laboratoire. Ces résultats ouvrent des nouvelles voies de recherche afin d’identifier les composants chimiques du furet et des plantes liés au comportement d’évitement des rongeurs, les prochaines étapes utilisant des animaux sauvages à la fois en laboratoire et sur le terrain. / Rodent commensal species produce great damage in agriculture and urban areas. As invasive species they can endanger local species and are carriers and vectors of several important zoonoses. Control methods rely mainly on the use of warfarins, which can be inadvertently be taken up by untargeted species. Warfarins have also lost their efficacy in rodents due to the development of genetic resistance. In addition, these methods are considered inhumane as they cause a slow and painful death due to haemorrhages. Olfaction is a main source for environmental risk assessment by rodents, and it can be used to modify their use of space. My aim in this thesis was to identify behavioural reactions of the house mouse (Mus musculus), using laboratory strains as models of wild animals, to ecologically meaningful chemical messages, including predator and plant chemical olfactory cues. My results showed that mice avoided complex ferret olfactory cues and ethanol which is a ubiquitous chemical related to fruit rotting and ripening. The feline protein Fel d 1, which belongs to the secretoglobin family and is a major cat allergen in humans, did not elicit significant avoidance or alter foraging behaviour in mice. However, Trimethylthiazoline purified from fox faeces, elicited clear avoidance behaviour and stress responses. I carried out a bibliographic review to evaluate and discuss rodent pest control methods from an ethical standpoint. This literature showed that many of the current methods of pest control are considered inhumane, and do not tally with current society concerns and welfare standards in other domains such as farms or laboratory animals. These results raise new research questions to identify ferret and plant chemical compounds that can induce rodent avoidance, and to carry out next stage of research with wild animals both under laboratory and field conditions.
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Creating Systems and Applying Large-Scale Methods to Improve Student Remediation in Online Tutoring Systems in Real-time and at ScaleSelent, Douglas A 08 June 2017 (has links)
"A common problem shared amongst online tutoring systems is the time-consuming nature of content creation. It has been estimated that an hour of online instruction can take up to 100-300 hours to create. Several systems have created tools to expedite content creation, such as the Cognitive Tutors Authoring Tool (CTAT) and the ASSISTments builder. Although these tools make content creation more efficient, they all still depend on the efforts of a content creator and/or past historical. These tools do not take full advantage of the power of the crowd. These issues and challenges faced by online tutoring systems provide an ideal environment to implement a solution using crowdsourcing. I created the PeerASSIST system to provide a solution to the challenges faced with tutoring content creation. PeerASSIST crowdsources the work students have done on problems inside the ASSISTments online tutoring system and redistributes that work as a form of tutoring to their peers, who are in need of assistance. Multi-objective multi-armed bandit algorithms are used to distribute student work, which balance exploring which work is good and exploiting the best currently known work. These policies are customized to run in a real-world environment with multiple asynchronous reward functions and an infinite number of actions. Inspired by major companies such as Google, Facebook, and Bing, PeerASSIST is also designed as a platform for simultaneous online experimentation in real-time and at scale. Currently over 600 teachers (grades K-12) are requiring students to show their work. Over 300,000 instances of student work have been collected from over 18,000 students across 28,000 problems. From the student work collected, 2,000 instances have been redistributed to over 550 students who needed help over the past few months. I conducted a randomized controlled experiment to evaluate the effectiveness of PeerASSIST on student performance. Other contributions include representing learning maps as Bayesian networks to model student performance, creating a machine-learning algorithm to derive student incorrect processes from their incorrect answer and the inputs of the problem, and applying Bayesian hypothesis testing to A/B experiments. We showed that learning maps can be simplified without practical loss of accuracy and that time series data is necessary to simplify learning maps if the static data is highly correlated. I also created several interventions to evaluate the effectiveness of the buggy messages generated from the machine-learned incorrect processes. The null results of these experiments demonstrate the difficulty of creating a successful tutoring and suggest that other methods of tutoring content creation (i.e. PeerASSIST) should be explored."
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Loose coupling and substitution principle in objet-oriented frameworks for web services / Couplage faible et principe de substitution dans les environnements à objets pour les services webAllam, Diana 10 July 2014 (has links)
Actuellement, l’implémentation des services (modèles SOAP et RESTful) et de leurs applications clientes est de plus en plus basée sur la programmation par objet. Ainsi, les cadriciels orientés-objets pour les services Web sont essentiellement composés de deux couches : une couche à objets qui enveloppe une couche à services. Dans ce contexte, deux principes sont nécessaires pour la spécification de ces cadriciels : (i) En premier lieu, un couplage faible entre les deux couches, ce qui permet de cacher la complexité des détails techniques de la couche à services dans la couche à objets et de faire évoluer la couche à services avec un impact minimal sur la couche à objets (ii) En second lieu, une interopérabilité induite par le principe de substitution associée au sous-typage dans la couche à objets. Dans cette thèse, nous présentons d’abord les faiblesses existantes dans les cadriciels orientés-objets liés à ces deux principes. Ensuite, nous proposons une nouvelle spécification pour ces cadriciels en vue de résoudre ces problèmes. Comme application, nous décrivons la mise en œuvre de notre spécification dans le cadriciel cxf, à la fois pour SOAP et RESTful. / Today, the implementation of services (SOAP and RESTful models) and of client applications is increasingly based on object-oriented programming languages. Thus, object-oriented frameworks for Web services are essentially composed with two levels: an object level built over a service level. In this context, two properties could be particularly required in the specification of these frameworks: (i)First a loose coupling between the two levels, which allows the complex technical details of the service level to be hidden at the object level and the service level to be evolved with a minimal impact on the object level, (ii) Second, an interoperability induced by the substitution principle associated to subtyping in the object level, which allows to freely convert a value of a subtype into a supertype. In this thesis, first we present the existing weaknesses of object-oriented frameworks related to these two requirements. Then, we propose a new specification for object-oriented Web service frameworks in order to resolve these problems. As an application, we provide an implementation of our specification in the cxf framework, for both SOAP and RESTful models.
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A potencialidade pedagógica do uso da lousa eletrônica: uma experiência em aulas de HistóriaElias, Maria Beatriz de Campos 18 August 2008 (has links)
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Previous issue date: 2008-08-18 / In the current scenery of the information society, the new communication and information tecnologies are affecting especially the professional and educational worlds. But do the multimedia messages, that already invaded classrooms, really
work? Richard Mayer s answer is yes, as he proposes his multimedia cognitive learning theory. And how have teachers been applying these techonological resources they now have access to? In order to answer this question, a ten day imersion was made on the Colégio Portinari in Salvador, concerning especially a history course in which the teacher uses multimedia sequences made by himself. / No cenário atual da sociedade da informação, as novas tecnologias da comunicação e da informação vêm afetando em particular o mundo do trabalho e o da educação. Mas as mensagens multimídias, que já invadiram as salas de aula, realmente funcionam? Sim, responde Richard Mayer, ao propor sua teoria cognitiva da aprendizagem multimídia. E na prática, como os professores vêm utilizando os recursos tecnológicos de que dispõem? Em busca da resposta a essa pergunta, fez-se uma imersão de dez dias no Colégio Portinari, de Salvador, onde leciona um professor de História que constrói suas próprias sequências multimídias.
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Peer Response to Messages of Distress: Do Sex and Content Matter?Barton, Alison L., Hirsch, Jameson K., Lovejoy, Christine M. 05 July 2013 (has links)
Background: Suicidal young adults often confide their distress to peers. It is unclear, however, what types of assistance a friend may offer in response to various symptoms of distress as well as whether the sex of either individual affects responses. Aims: We examined open-ended responses to e-mail vignettes from a fictitious friend exhibiting depressed, irritable, or overtly suicidal communications. Method: College student participants (n = 106) read e-mail messages from a fictitious friend, to which they composed a reply. Replies were coded to reflect the presence/absence of mention of professional help, problem-oriented (personal) help, and social support. Results: Problem-oriented help was offered the most across conditions; professional help was offered least in response to depressed or irritable vignettes. Women were more likely to offer any type of help than men. Patterns of help-giving and sex differences in help-giving varied by condition. Conclusions: Results indicate students’ preferences for solving peer problems personally rather than professionally. Campus prevention and intervention efforts should focus on enhancing students’ peer support and referral skills.
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Perspectives of Young Adults Toward Tobacco UseOmoalako-Adesanya, Caroline Oluwatosin 01 January 2016 (has links)
Conditions related to tobacco use constitute the single most preventable cause of death in the United States. Approximately 443,000 U.S. adults die each year from smoking-related illnesses. During young adulthood, social and behavioral changes occur; experimentation with tobacco products such as cigarettes is common and may lead to a habit of smoking. A gap was identified in the literature on the perceived impact of family communication on young adults' decisions regarding smoking. The purpose of this descriptive phenomenological study was to address this gap by gathering information on the perspectives of young adults toward tobacco use. Fifteen young adults aged 18 to 26 from the northeastern region of New Jersey who were currently engaged in the use of tobacco products participated in open-ended interviews. Research questions were designed to investigate young adults' views and perceptions regarding cigarette use and to explore information regarding how smoking-related communication received from family members influenced young adults' decision to smoke. The theory of planned behavior and social learning theory provided the theoretical underpinnings and consistent themes by young adults from the study. Van Manen's data analysis strategy demonstrated thematic reports from young adults that behaviors, habits, attitudes, communications, including verbal and nonverbal cues and practices are learned from their parental figures in the home environment. Recommendations for future research include exploring young adults from other geographical locations regarding their perspectives toward tobacco use. This study may promote positive social change for the public and health practitioners by providing insight on family interactions regarding smoking behaviors for young adults..
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The role of communication messages and explicit niching in distributed evolutionary multi-objective optimizationBui, Lam Thu, Information Technology & Electrical Engineering, Australian Defence Force Academy, UNSW January 2007 (has links)
Dealing with optimization problems with more than one objective has been an important research area in evolutionary computation. The class of multi-objective problems (MOPs) is an important one because multi-objectivity exists in almost all aspects of human life; whereby there usually exist several compromises in each problem. Multi-objective evolutionary algorithms (MOEAs) have been applied widely in many real-world problems. This is because (1) they work with a population during the course of action, which hence offer more flexible control to find a set of efficient solutions, and (2) real-world problems are usually black-box where an explicit mathematical representation is unknown. However, MOEAs usually require a large amount of computational effort. This is a sub- stantial challenge in bringing MOEAs to practice. This thesis primarily aims to address this challenge through an investigation into issues of scalability and the balance between exploration and exploitation. These have been outstanding research challenges, not only for MOEAs, but also for evolutionary algorithms in general. A distributed framework of local models using explicit niching is introduced as an overarching umbrella to solve multi-objective optimization problems. This framework is used to address the two-part question about first, the role of communication messages and second, the role of explicit niching in distributed evolutionary multi-objective optimization. The concept behind the framework of local models is for the search to be conducted locally in different areas of the decision search space, which allows the local models to be distributed on different processing nodes. During the optimization process, local models interact (exchange messages) with each other using rules inspired from Particle Swarm Optimization (PSO). Hence, the hypothesis of this work is that running simultaneously several search engines in different local areas is better for exploiting local information, while exchanging messages among those diverse engines can provide a better exploration strategy. For this framework, as the models work locally, they gain access to some global knowledge of each other. In order to validate the proposed framework, a series of experiments on a wide range of test problems was conducted. These experiments were motivated by the following studies which in their totality contribute to the verification of our hypothesis: (1) studying the performance of the framework under different aspects such as initialization, convergence, diversity, scalability, and sensitivity to the framework's parameters, (2) investigating interleaving guidance in both the decision and objective spaces, (3) applying local models using estimation of distributions, (4) evaluating local models in noisy environments and (5) the role of communication messages and explicit niching in distributed computing. The experimental results showed that: (1) the use of local models increases the chance of MOEAs to improve their performance in finding the Pareto optimal front, (2) interaction strategies using PSO rules are suitable for controlling local models, and that they also can be coupled with specialization in order to refine the obtained non-dominated set, (3) estimation of distribution improves when coupled with local models, (4) local models work well in noisy environments, and (5) the communication cost in distributed systems with local models can be reduced significantly by using summary information (such as the direction information naturally determined by local models) as the communication messages, in comparison with conventional approaches using descriptive information of individuals. In summary, the proposed framework is a successful step towards efficient distributed MOEAs.
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