No description available.

Research on racial border patrolling has demonstrated how people police racial borders in order to maintain socially constructed differences and reinforce divisions between racial groups and their members. Existing literature on border patrolling has primarily focused on white/black couples and multiracial families, with discussions contrasting “white border patrolling” and “black border patrolling,” in terms of differential motivations, intentions, and goals (Dalmage 2000). In my dissertation research, I examined a different type of policing racial categories and the spaces in-between these shifting boundaries. I offer up “multiracial interracial border patrolling” as a means of understanding how borderism impacts the lives of “multiracial” individuals in “interracial” relationships. In taking a look at how both identities and relationships involve racial negotiations, I conducted 60 in-depth, face-to-face qualitative interviews with people who indicated having racially mixed parentage or heritage. Respondents shared their experiences of publicly and privately managing their sometimes shifting preferred racial identities; often racially ambiguous appearance; and situationally in/visible “interracial” relationships in an era of colorblind racism. This management included encounters with border patrolling from strangers, significant others, and self. Not only did border patrolling originate from these three sources, but also manifested itself in a variety of forms, including benevolent (positive, supportive); beneficiary (socially and sometimes economically or materially beneficial); protective, and malevolent (negative, malicious, conflictive). Throughout, I discussed the border patrolling variations that “multiracial” individuals in “interracial” relationships face. I also worked to show how people’s participation in border patrolling encouraged their production of colorblind discourses as a strategy for masking their racial attitudes and ideologies about “multiracial” individuals in “interracial” relationships.

The revolution of autonomous vehicles has led to the development of robots with abundant sensors, actuators with many degrees of freedom, high-performance computing capabilities, and high-speed communication devices. These robots use a large volume of information from sensors to solve diverse problems. However, this usually leads to a significant modeling burden as well as excessive cost and computational requirements. Furthermore, in some scenarios, sophisticated sensors may not work precisely, the real-time processing power of a robot may be inadequate, the communication among robots may be impeded by natural or adversarial conditions, or the actuation control in a robot may be insubstantial. In these cases, we have to rely on simple robots with limited sensing and actuation, minimal onboard processing, moderate communication, and insufficient memory capacity. This reality motivates us to model simple robots such as bouncing and underactuated robots making use of the dynamical system techniques. In this dissertation, we propose a four-pronged approach for solving tasks in resource-constrained scenarios: 1) Combinatorial filters for bouncing robot localization; 2) Bouncing robot navigation and coverage; 3) Stochastic multi-robot patrolling; and 4) Deployment and planning of underactuated aquatic robots. First, we present a global localization method for a bouncing robot equipped with only a clock and contact sensors. Space-efficient and finite automata-based combinatorial filters are synthesized to solve the localization task by determining the robot’s pose (position and orientation) in its environment. Second, we propose a solution for navigation and coverage tasks using single or multiple bouncing robots. The proposed solution finds a navigation plan for a single bouncing robot from the robot’s initial pose to its goal pose with limited sensing. Probabilistic paths from several policies of the robot are combined artfully so that the actual coverage distribution can become as close as possible to a target coverage distribution. A joint trajectory for multiple bouncing robots to visit all the locations of an environment is incrementally generated. Third, a scalable method is proposed to find stochastic strategies for multi-robot patrolling under an adversarial and communication-constrained environment. Then, we evaluate the vulnerability of our patrolling policies by finding the probability of capturing an adversary for a location in our proposed patrolling scenarios. Finally, a data-driven deployment and planning approach is presented for the underactuated aquatic robots called drifters that creates the generalized flow pattern of the water, develops a Markov-chain based motion model, and studies the long- term behavior of a marine environment from a flow point-of-view. In a broad summary, our dynamical system approach is a unique solution to typical robotic tasks and opens a new paradigm for the modeling of simple robotics systems

No description available.

Police officers with patrolling duties are exposed to physically demanding situations on a regular basis, which puts a high demand on their physical abilities and condition. Police officers are regularly forced to make quick decisions in complex tactical situations which in some cases mean physical confrontation. Throughout the procedure to become a Swedish Police Officer, there are tests that measure the physical condition of future police officers from the day they are recruited, until they leave the school. Then, however, the testing stops. Therefore, the majority of the physical training throughout the career of a police officer is carried out on their own initiative, and in their spare time. But what do the individual officers think about their physical condition and resilience in relation to everyday work? Studies have shown that police officers who often think about the risk of being injured during interventions, or the dangers associated with their work, experience more stress than other police officers. The knowledge on how to increase the safety and security for police officers in situations where violence may occur, which should contribute to greater room for action in situations is scarce. The aim of the present investigation is to increase our understanding and fill a knowledge gap for the police officers resilience in with regards to physical confrontation on duty within the Swedish Police conflict management training program (POLKON). The studie is based on a qualitative method using semi-structured interviews among Swedish police officers. The respondents have answered questions regarding their view on physical sustainability in relation to their work. Thematic analysis has been conducted and a number of themes have been generated which will be presented.

Pouvoir lutter efficacement contre certains fléaux comme les incendies de forêt, les feux de brousse ou les catastrophes naturelles constitue un enjeu majeur dans plusieurs villes du monde.Avec l'avènement de la technologie de pointe représentée par les réseaux de capteurs, la détection de ces phénomènes devient plus aisée.En effet, des capteurs peuvent être déployés dans des zones difficiles d'accès et s'ils sont suffisamment nombreux pour couvrir la totalité de l'environnement à surveiller, une alerte peut être directement donnée par le capteur ayant détecté un certain type d'évènement (feu, secousse sismique...).Le centre de contrôle ayant reçu l'alerte peut ensuite décider d'intervenir sur la zone en cause.Nos travaux se situent dans ce cadre de la détection de phénomènes par un réseau de capteurs, en supposant que l'environnement est connu et que les capteurs sont mobiles, sans fil et en nombre insuffisant pour couvrir la totalité de l'environnement à surveiller.Parler de surveillance par un nombre faible d'entités mobiles nécessite de parcourir régulièrement certaines zones critiques de l'environnement, ce qui peut s'apparenter à une tâche de patrouille.Dans le cadre de cette thèse, nous nous sommes focalisés sur la détermination de stratégies de patrouille multi-capteurs appliquée à la détection d'évènements.Un problème similaire au nôtre est celui de la patrouille multi-agents dans un environnement connu.Ce problème consiste à faire visiter régulièrement les noeuds d'un graphe (représentant l'environnement) par des agents.Les capteurs peuvent être considérés comme des agents ayant des ressources limitées, en terme d'énergie en particulier.Le cadre de la patrouille multi-agents et les techniques proposées pour le résoudre ne peuvent pas être utilisés ici.Après avoir formulé mathématiquement le problème de la patrouille multi-capteurs appliquée à la détection d'évènements, nous proposons une technique de résolution approchée basée sur des colonies de fourmis.Des simulations ont été réalisées en considérant différents scenarii (topologies d'environnement, populations de capteurs, apparitions des événements) afin d'évaluer la pertinence de notre approche.Les résultats expérimentaux montrent que notre approche permet de déterminer des stratégies de patrouille satisfaisantes dans la majorité des scenarii. / To fight effectively against scourges like forest fires , brush fires or natural disasters is a major issue in many cities worldwide.With the advent of technology represented by sensor networks , detection of these phenomena becomes easier .Indeed , sensors can be deployed in remote areas and they are enough to cover the entire environment to monitor, an alert can be given directly by the sensor has detected a certain type of event (fire, earthquake ... ) .The control center has received the alert may then decide to intervene in the area in question .Our work takes place in the context of the detection of phenomena by a sensor network , assuming that the environment is known and that the sensors are mobile, wireless and insufficient to cover the entire environment to be monitored.Speaking of monitoring a small number of mobile entities requires regularly browse some critical environmental areas, which can be likened to a patrol task .In this thesis , we focused on identifying strategies patrol multi-sensor applied to the detection of events.A similar problem to ours is the multi-agent patrolling in a known environment .This problem is to regularly visit the nodes of a graph (representing the environment) by agents.The sensors can be considered as agents with limited resources , in terms of energy in particular.The framework of multi- agents and techniques proposed to solve patrol can not be used here .After mathematically formulated the problem of multi-sensor patrol applied to the detection of events, we propose an approximate solution technique based on ant colonies .Simulations were made ​​considering different scenarios ( environmental topologies populations sensors appearances events ) to assess the relevance of our approach.The experimental results show that our approach identifies strategies patrol satisfactory in the majority of scenarios.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-03-09T12:13:05Z No. of bitstreams: 1 rafaeljosefonsecadesa.pdf: 2699281 bytes, checksum: ca2455c138265324b1a8fcbb6075da41 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-10T12:58:01Z (GMT) No. of bitstreams: 1 rafaeljosefonsecadesa.pdf: 2699281 bytes, checksum: ca2455c138265324b1a8fcbb6075da41 (MD5) / Made available in DSpace on 2017-03-10T12:58:01Z (GMT). No. of bitstreams: 1 rafaeljosefonsecadesa.pdf: 2699281 bytes, checksum: ca2455c138265324b1a8fcbb6075da41 (MD5) Previous issue date: 2016-09-09 / Com a evolução da tecnologia, estão aumentando as aplicabilidades dos robôs em nosso meio. Em alguns casos, a utilização de sistemas com múltiplos robôs autônomos trabalhando em cooperação se torna uma ótima alternativa. Há várias pesquisas em andamento na área de robótica com o intuito de aprimorar estas tarefas. Entre estas pesquisas estão os sistemas de patrulhamento. Neste trabalho, o sistema de patrulhamento utilizando múltiplos robôs é implementado considerando a série de chegada de alertas nas estações de monitoramento e o robô pode andar somente em uma única direção. Devido ao número de estações que podem entrar em alerta e ao número de robôs, o controle desse sistema se torna complexo. Como a finalidade de um sistema de patrulhamento é atender possíveis alertas de invasores, é imprescindível que haja uma resposta rápida do controlador responsável para que um robô logo seja encaminhado com o propósito de atender a esse alerta. No caso de sistemas com múltiplos robôs, é necessário que haja uma coordenação do controlador para que os robôs possam atender o máximo de alertas possíveis em um menor instante de tempo. Para resolver esse problema, foi utilizado um controlador composto por uma técnica inteligente de otimização bioinspirada chamada de “Algoritmo Genético” (AG). Este controlador centraliza todas as decisões de controle dos robôs, sendo responsável por orientá-los em relação aos movimentos e captação de informação. As decisões são tomadas com o intuito de maximizar a recompensa do sistema. Esta recompensa é composta pelo ganho de informação do sistema e por uma penalização gerada pela demora em atender aos alertas ativados. Foram feitas simulações com a intenção de verificar a eficácia desse controlador, comparando-o com um controlador utilizando heurísticas pré-definidas. Essas simulações comprovaram a eficiência do controlador via Algoritmo Genético. Devido ao fato do controlador via AG analisar o sistema como um todo enquanto que o controlador heurístico analisa apenas o estágio atual, foi possível observar que a distribuição dos robôs no mapa permitia um atendimento mais ágil às estações com alerta ativados, assim como uma maior aquisição de informações do local. Outro fato importante foi em relação à complexidade do sistema. Foi notado que quanto maior a complexidade do sistema, ou seja, quanto maior o número de robôs e de estações, melhor era a eficiência do controlador via Algoritmo Genético em relação ao controlador heurístico. / New technologies have been considerable advances, and consequently, thus allows the robot appearance as an integral part of our daily lives. In recent years, the design of cooperative multi-robot systems has become a highly active research area within robotics. Cooperative multi-robot systems (MRS) have received significant attention by the robotics community for the past two decades, because their successful deployment have unquestionable social and economical relevance in many application domain. There are several advantages of using multi-robot systems in different application and task. The development and conception of patrolling methods using multi-robot systems is a scientific area which has a growing interest. This work, the patrol system using multiple robots is implemented considering the series of arrival of alerts in the monitoring stations known and the robot was limited to move in one direction. Due to the large number of stations that can assume alert condition and due to the large number of robots, the system control becomes extremely complex. Patrol systems are usually designed for surveillance. An efficient controller permits a patrol in a way that maximizes their chances of detecting an adversary trying to penetrate through the patrol path. The obvious advantage of multi-robot exploration is its concurrency, which can greatly reduce the time needed for the mission. Coordination among multiple robots is necessary to achieve efficiency in robotic explorations. When working in groups, robots need to coordinate their activities. However, a Genetic Algorithm approach was implemented to carryout an optimized control action provided from the controller. In fact the controller determines the robot's behavior. The decision strategies are implemented in order to maximize the system response. The present work deals with a computational study of controller based on Genetic Algorithm and it comparison with another controller based pre-defined heuristics. The simulation results show the efficiency of the proposed controller based on Genetic Algorithm, when compared with the controller based on heuristics. The right decisions from the controller based on Genetic Algorithm allowed a better distribution of the robots on the map leading to fast service stations with active alert, as well as increased acquisition of location information. Another important fact was regarding the complexity of the system. Also, as a result, it was noticed an excellent efficiency of the controller based on Genetic Algorithm when the existence of the large number of robots and stations.

Background. Police work is a stressful occupation with frequent exposure to traumatic events and psychological strain from work might increase the risk of burnout. This thesis focuses on patrolling police officers (PPO), who work most of their time in the community and have daily contact with the public. Since police work traditionally is a male coded occupation we assume that there are differences between women and men in burnout as well as experiences from psychosocial work environment. Aim. The overall aim of this thesis is to explore burnout, psychosocial and physical work environment, coping strategies, and stress of conscience when taking gender into consideration among patrolling police officers. Methods. This thesis employs both qualitative and quantitative methods. In Paper I a qualitative approach with narrative interviews was used where male PPO described experiences of traumatic situations when caring for victims of traffic accidents. A convenience sample of nine male PPO from a mid-sized police authority was recruited. Interviews were analyzed using qualitative content analysis. Papers II, III, and IV were based on a cross-sectional survey from a randomly selected sample stratified for gender from all 21 local police authorities in Sweden. In the final sample, 1554 PPOs were invited (778 women, 776 men), response rate was 55% (n=856) in total, 56% for women (n=437) and 53% for men (n=419). The survey included a self-administered questionnaire based on instruments measuring burnout, stress of conscience, psychosocial and physical work environment, and coping. Results. Findings from Paper I were presented in three themes; “being secure with the support system,” “being confident about prior successful actions,” and “being burdened with uncertainty.” Results from Paper II showed high levels of emotional exhaustion (EE), 30% for female PPOs and 26% for male PPOs. High levels of depersonalization (DP) were reported for 52 % of female PPO, corresponding proportions for male were 60%. Multiple logistic regression showed that stress of conscience (SCQ-A), high demand, and organizational climate increased the risk of EE for female PPO. For male PPO stress of conscience (SCQ-A), low control and high demand increased the risk of EE. Independent of gender, stress of conscience (SCQ-A) increased the risk of DP. Psychometric properties of the WOCQ were investigated with exploratory factor analysis and confirmatory factor analysis, a six-factor solution was confirmed. DIF analysis was detected for a third of the items in relation to gender. In Paper IV a block wise hierarchical multiple regression analysis was performed investigating the predictive impact of psychological demand, decision latitude, social support, coping strategies, and stress of conscience on EE as well as DP. Findings revealed that, regardless of gender, risk of EE and DP increased with a troubled conscience amongst the PPO. Conclusion. “Being burdened with uncertainty” in this male-dominated context indicate that the PPO did not feel confident talking about traumatic situations, which might influence their coping strategies when arriving to a similar situation. This finding can be related to Paper II and IV showing that stress of conscience increased the risk of both EE and DP. The associations between troubled conscience and the risk of experiencing both emotional exhaustion and depersonalization indicate that stress of conscience should be considered when studying the influence of the psychosocial work environment on burnout. Results from this study show that the psychosocial work environment is not satisfying and needs improvement for patrolling police officers in Sweden. Further studies including both qualitative and quantitative (longitudinal) methods should be used to improve knowledge in this area to increase conditions for preventive and rehabilitative actions.

The aim of this paper was to explore associations between previous victimization, police legitimacy and feelings of safety, and to also explore how different patrolling strategies were perceived in terms of general feelings of safety and police legitimacy. A questionnaire was created to measure these variables. The tests used were correlations and independent samples t-tests. The participants were 175 individuals living in Sweden, 67 were men and 108 were women, and the average age was 28. The correlation analysis showed that there was no significant relation between police legitimacy and feelings of safety regardless of previous victimization or not. One t-test showed no significant difference in patrolling strategies in terms of feelings of safety. However, a second t-test showed a significant difference in patrolling strategies in the general perception of police legitimacy. Participants with greater confidence in the police, perceived foot patrolling as more vital for their feelings of safety. The theory, Community oriented policing (COP), was used to further analyze results obtained within this study. Through this study, it was concluded that foot patrolling could promote cooperation between the police and the public. This might improve citizens' understanding of police legitimacy, which in turn can increase the overall levels of feelings of safety among the public. / Syftet med denna studie var att undersöka samband mellan tidigare viktimisering, tilltro till polisen och upplevd trygghet, samt skillnader i vilken patrulleringsstrategi som uppfattades som mest trygg vad gäller den generella upplevda tryggheten respektive den generella tilltron till polisen. En webbenkät som mätte dessa variabler skapades och analyserades sedan med hjälp av korrelationsanalyser och oberoende t-test. Antalet deltagare var 175 personer bosatta i Sverige där 67 var män och 108 var kvinnor och deras medelålder var 28. Korrelationsanalyserna visade inget signifikant samband mellan tilltro till polisen och upplevd trygghet även när tidigare viktimisering användes som kontrollvariabel. Det oberoende t-testet visade ingen signifikant skillnad i vilken patrulleringstrategi som deltagarna uppfattade som mest trygg vad gäller den generella upplevda tryggheten. Däremot visade ytterligare ett oberoende t-test att det fanns en signifikant skillnad i vilken patrulleringsstrategi deltagarna uppfattade som mest trygg vad gäller den generella tilltron till polisen, där personer med högre tilltro till polisen uppfattade fotpatrullering som mest tryggt. Teorin om Community oriented policing (COP) användes för att analysera resultaten. Sammanfattningsvis stödjer denna studies resultat uppfattningen om att fotpatrullering kan främja samarbetet mellan invånare och polis. Ökat samarbete mellan parterna kan tänkas leda till ökad tilltro till polisen, som i sin tur kan resultera i ökad upplevd trygghet bland befolkningen.

La détection et le suivi de cibles sont des missions fréquentes pour la robotique mobile, que le contexte soit civil, industriel ou militaire. Ces applications constituent un domaine de choix pour la planification multirobot, et sont abordées par de multiples communautés selon différents points de vue. Nous proposons dans un premier temps une taxonomie commune qui permetde regrouper et de comparer les différentes approches de ces problèmes, afin de mieux les analyser et de mettre en évidence leurs lacunes respectives. En particulier, on note la faible représentativité des modèles exploités, peu expressifs : la plupart des algorithmes évoluent dans un monde en deux dimensions où les observations et le déplacement sont conditionnés par lesmêmes obstacles. Ces modèles éloignés de la réalité nous semblent trop restrictifs pour pleinement exploiter la synergie des équipes multirobot hétérogènes : nous proposons une organisation des différents modèles nécessaires, en explicitant une séparation claire entre modèles et algorithmes de planification. Cette organisation est concrétisée par une librairie qui structure lesmodèles disponibles et définit les requêtes nécessaires aux algorithmes de planification. Dans un second temps, nous proposons un ensemble d’algorithmes utilisant les modèles définis précédemment pour planifier des missions de patrouille de zones et de poursuite de cibles. Ces algorithmes s’appuient sur un formalisme mathématique rigoureux afin d’étudier l’impact des modèlessur les performances. Nous analysons notamment l’impact sur la complexité – c’est-à-dire en quoi des modèles plus élaborés impactent la complexité de résolution – et sur la qualité des solutions résultantes, indépendamment des modèles, selon des métriques usuelles. D’une manière plus générale, les modèles sont un lien essentiel entre l’Intelligence Artificielle et la Robotique : leur enrichissement et leur étude approfondie permettent d’exhiber des comportements plus efficaces pour la réussite des missions allouées aux robots. Cette thèse contribue à démontrer l’importance des modèles pour la planification et la conduite de mission multirobots. / Detecting, localizing or following targets is at the core of numerous robotic applications in industrial, civilian and military application contexts. Much work has been devoted in various research communities to planning for such problems, each community with a different standpoint. Our thesis first provides a unifying taxonomy to go beyond the frontiers of specific communities and specific problems, and to enlarge the scope of prior surveys. We review various work related to each class of problems identified in the taxonomy, highlighting the different approaches, models and results. This analysis specifically points out the lack of representativityof the exploited models, which are in vast majority only 2D single-layer models where motion and sensing are mixed up. We consider those unrealistic models as too restrictive to handle the full synergistic potential of an heterogeneous team of cooperative robots. In response to this statement, we suggest a new organisation of the necessary models, stating clearly the links and separation between models and planning algorithms. This has lead to the development of a C++ library that structures the available models and defines the requests required by the planning process. We then exploit this library through a set of algorithms tackling area patrolling and target tracking. These algorithms are supported by a sound formalism and we study the impact of the models on the observed performances, with an emphasis on the complexity and the quality of the resultingsolutions. As a more general consideration, models are an essential link between Artificial Intelligence and applied Robotics : improving their expressiveness and studying them rigorously are the keys leading toward better robot behaviours and successful robotic missions. This thesis help to show how important the models are for planning and other decision processes formulti-robot missions.