2,757 research outputs found
Collaborative search and rescue by autonomous robots
No full textIn recent years, professional first responders have started to use novel technologies at the scene of disasters in order to save more lives. Increasingly, they use robots to search disaster sites. One of the most widely and successfully used robot platforms in the disaster response domain are unmanned aerial vehicles (UAVs). UAVs allow remote inspection and mapping. They are able to provide high resolution imagery and often need minimal infrastructure to fly. This allows settings where multiple UAVs are airborne accelerating the information gathering from the disaster site. However, current deployments use labour intensive, individually teleoperated UAVs. Given this, there is a drive toward using multiple robots operating with a certain level of autonomy, in order to decrease the operators' workload. One approach for utilising multiple robots in this way is semi-autonomous operation supervised by a small number of professionals; only requiring human experts for crucial decisions. Current commercial UAV platforms also allow the deployment of a diverse group of robots, allowing them to combine their individual capabilities to be more efficient. For example, fixed-wing UAVs are capable of flying faster and carry larger payload, but when they do so, they should be deployed with higher safety measures (safety pilots are required for non-lightweight aircraft). On the other hand, small rotary-wing UAVs are more agile and can approach and provide imagery about objects on the ground.To this end, this thesis develops a number of new approaches for the collaboration of a heterogeneous group of robots in disaster response. More specifically, the problem of collaborative planning with robots operating in an uncertain workflow based setting is investigated by solving the search and rescue (SAR) collaboration problem. Of course, the problem complexity increases when collaborating with different robots. It is not different in this setting, the actions of different types of robots need to be planned with dependencies between their actions under uncertainty.To date, research on collaboration between multiple robots has typically focused on known settings, where the possible robot actions are defined as a set of tasks. However, in most real world settings, there is a significant amount of uncertainty present. For example, information about a disaster site develops gradually during disaster relief, thus initially there is often very little certainty about the locations of people requiring assistance (e.g. damaged buildings, trapped victims, or supply shortages). Existing solutions that tackle collaboration in the face of uncertain information are typically limited to simple exploration or target search problems. Moreover, the use of generic temporal planners rapidly becomes intractable for such problems unless applied in a domain-specific manner. Finally, domain specific approaches rarely involve complex action relations, such as task dependencies where the actions of some robots are built on the actions of others. When they do so, decomposition techniques are applied to decrease the problem complexity, or simple heuristics are applied to enhance similar collaboration. Such approaches often lead to low quality solutions, because vital action dependencies across different roles are not taken into account during the optimisation.Against this background, we offer novel online planning approaches for heterogeneous multi-robot collaboration under uncertainty. First, we provide a negotiation-based bidirectional collaborative planning approach that exploits the potential in determinisation via hindsight optimisation (HOP) combined with long-term planning. Second, we extend this approach to create an anytime Monte Carlo tree search planner that also utilises HOP combined with long-term planning. In online planning settings, such as SAR, anytime planners are beneficial to ensure the ability of providing a feasible plan within the given computational budget. Third, we construct a scenario close to physical deployment that allows us to show how our long-term collaborative planning outperforms the current state of the art path-planning approaches by 25 %.We conclude that long-term collaborative planning under uncertainty provides an improvement when planning in SAR settings. When combined, the contributions presented in this thesis represent an advancement in the state of the art in the field of online planning under uncertainty. The approaches and methods presented can be applied in collaborative settings when uncertainty plays an important role for defining dependencies between partial planning problems..<br/
External interventions and the duration of civil wars
No full textThe authors combine an empirical model of external intervention, with a theoretical model of civil war duration. Their empirical model of intervention allows them to analyze civil war duration, using"expected"rather than"actual"external intervention as an explanatory variable in the duration model. Unlike previous studies, they find that external intervention is positively associated with the duration of civil war. They distinguish partial third-party interventions that extend the length of war, from multilateral"peace"operations, which have a mandate to restore peace without taking sides - and which typically take place at war's end, or at least when both sides have agreed to a cease-fire. In a future paper, the authors will examine whether partial third-party interventions - whatever their effect on a war's duration - increase the risk of war's recurrence. If that proves true, then even if interventions reduce the length of civil war, they may do so at the cost of further destabilizing the political system, and sowing the seeds of future rebellion.Children and Youth,Peace&Peacekeeping,Post Conflict Reconstruction,Post Conflict Reconstruction,International Affairs,Post Conflict Reconstruction,Social Conflict and Violence,Peace&Peacekeeping,Post Conflict Reconstruction,International Affairs
Collaborative online planning for automated victim search in disaster response
No full textCollaboration is essential for effective performance by groups of robots in disaster response settings. Here we are particularly interested in heterogeneous robots that collaborate in complex scenarios with incomplete, dynamically changing information. In detail, we consider an automated victim search setting, where unmanned aerial vehicles (UAVs) with different capabilities work together to scan for mobile phones and find and provide information about possible victims near these phone locations. The state of the art for such collaboration is robot control based on independent planning for robots with different tasks and typically incorporates uncertainty with only a limited scope. In contrast, in this paper, we take into account complex relations between robots with different tasks. As a result, we create a joint, full-horizon plan for the whole robot team by optimising over the uncertainty of future information gain using an online planner with hindsight optimisation. This joint plan is also used for further optimisation of individual UAV paths based on the long-term plans of all robots. We evaluate our planner’s performance in a realistic simulation environment based on a real disaster and find that our approach finds victims 25% faster compared to current state-of-the-art approaches
Sisyphus in Kertész\u27s Fatelessness
No full textIn his article Sisyphus in Kertész\u27s Fatelessness Eric Beck Rubin discusses Imre Kertész\u27s novel in relation to the philosophy of eternal recurrence, namely the notion that an individual inhabits a universe made of finite possibilities experienced and re-experienced without variation or end. Early explorations of eternal recurrence by Friedrich Nietzsche were taken up by Albert Camus, and Beck Rubin argues that certain works by both authors are fundamental to any reading of Fatelessness. Further, Beck Rubin argues that Kertész\u27s contribution to the debate can be viewed from two perspectives: one sees Kertész as an author in conversation with fellow authors writing his own allegory of Sisyphus, the character who embodies eternal recurrence, and the other looks at Kertész as a writer who turns Sisyphus into a symbol subject to ironic reinterpretation. Through such a process, Kertész turns the world of the concentration camps into the original Tartarus
Prince Edward Island in the 'Age of Discovery': an exhibition of maps and engravings from the collection of James W. MacNutt
No full texttext by Boyde Beck and Edward MacDonald.; Catalogue of an exhibition held 13 September to 25 October, 1992, Confederation Centre Art Gallery and Musuem.; Front and back cover illustration of map "Nova Scotia Drawn from Surveys By T Kitching"
A minimal-distance chromatic polynomial for signed graphs
No full textIn the early 20th century the chromatic polynomial was introduced as a way to count the proper colorings of a graph. It was generalized to signed graphs, graphs consisting of an unsigned graph and a signing function that labels each edge with a positive or negative sign. In 2009 Babson and Beck developed a two-variable chromatic polynomial for unsigned graphs by requiring colors of adjacent nodes in a graph to be a minimal-color apart. We extend this idea to signed graphs for integral and modular coloring values, showing in both cases that the counting function is a piecewise-defined quasipolynomial of period 1 or 2. Furthermore, we establish a reciprocity relationship that mirrors Stanley's reciprocity theorem on the chromatic polynomial for an unsigned graph
The relationship between depression and self-mutilation in adolescence
No full textPlan BThe importance of the relationship between depression and self-mutilation in the adolescent population is becoming more apparent. Analysis of these two variables demonstrates that they are correlated with one another in the adolescent population. The present study examines the relationship between depression and self-mutilation. Two scales, the Beck Depression Inventory II (Beck, 1996) and the Self-Harm Survey (Conterio, Lader, & Bloom, 1998) were administered to participants and the scores were correlated to determine whether a relationship existed between the two variables. Participants were residents from a residential treatment center for adolescents. Data analysis using Pearson’s r correlation coefficients were used to determine if there was a positive correlation between depression and self-mutilation. The t-test for independent means was utilized to determine if there was a difference between gender and self-mutilation, age and self-mutilation, as well as length of stay in the residential treatment facility and self-mutilation. The means and standard deviations were also determined for these variables. Statistical differences were indicated based on these findings. Implications of this study as well as recommendations for future studies on depression and self-mutilation were discussed in detail
Para uma música borreama
No full textAfreudite : Revista Lusófona de Psicanálise Pura e AplicadaO autor explora a Composição Musical pela via de RSI e do Nó Borromeano no ensino de Jacques Lacan. Também elabora propostas técnicas e estéticas para uma Música Borromeana.The author explores the Musical Composition with the concepts of RSI and Borromean Ring in Jacques Lacan's teaching. He also elaborates some technicals and estheticals propositions for a Borromean Music
Risco e cosmopolitismo: ambiente, modernidade e Europa no pensamento de Ulrich Beck
No full textTese de mestrado em Filosofia da Natureza e do Ambiente apresentada à Faculdade de Letras da Universidade de Lisboa, 2008Esta dissertação insere-se nas áreas de Filosofia do Ambiente e Filosofia Política e pretende levar a cabo a análise do pensamento de Ulrich Beck, sociólogo alemão e autor da obra Risk Society. Partindo do conceito de Sociedade de Risco elaborado por Beck, tenta-se averiguar a forma como a presença do risco nas sociedades contemporâneas, sociedades industrialmente avançadas dominadas pela incerteza e pela insegurança devido à eclosão de desastres ambientais e tecnológicos de dimensão global e cujas efeitos não são totalmente previsíveis, conduziu a importantes alterações nas principais instâncias responsáveis pelo desenvolvimento do projecto da Modernidade - ciência, tecnologia e política -, provocando com isso um clima de descontinuidade e ruptura com os paradigmas fundamentais do pensamento moderno, nomeadamente com o seu paradigma tecnocientífico fundado no século XVII por Francis Bacon e Descartes, obrigando o momento actual da Modernidade a uma confrontação crítica com as consequências nocivas das suas inúmeras conquistas , algo que Beck designa como Modernidade Reflexiva. Perante ameaças de dimensão global, a solução para os problemas da Sociedade de Risco consiste num esforço de cooperação internacional a nível das instituições políticas. Nesse sentido, tenta-se averiguar, na segunda parte deste estudo, a forma como o Cosmopolitismo, como elemento primordial de uma nova cultura política em era de globalização, e a Europa, como modelo de instituições transnacionais, poderão contribuir para a resolução das diversas ameaças com que se confrontada a sociedade contemporânea.This dissertation has been made in the fields of Environmental Philosophy and Political Philosophy and intends to examine the thought of Ulrich Beck, German sociologist and author of the book entitled Risk Society. Taking the concept of Risk Society developed by Beck, we try to investigate the way the presence of risk in contemporary societies, industrially developed societies ruled by uncertainty and insecurity due to rising of environmental and technological threats of global scope and whose effects can't be totally predicted, has led to fundamental changes in the main authorities in charge of the project of Modernity science, technology and politics -, causing a breakthrough with the fundamental thesis of modern thought, mainly with its technocientific paradigm started in the 17th century by Francis Bacon and Descartes, compelling the present moment of Modernity to a critical confrontation with the harmful consequences of its countless victories, something that Beck calls Reflexive Modernization. In the presence of threats with a global scope, the solution to the problems of Risk Society can only be international cooperation on the level of political institutions. Being so, on the second part of this dissertation, we focus our attention in Cosmopolitanism, as an essential element of a new political culture in the age of globalization, and Europe, as a model of transnational institutions, can contribute to the solution of the several threats faced by contemporary society
Risco e cosmopolitismo: ambiente, modernidade e Europa no pensamento de Ulrich Beck
No full textTese de mestrado em Filosofia da Natureza e do Ambiente apresentada à Faculdade de Letras da Universidade de Lisboa, 2008Esta dissertação insere-se nas áreas de Filosofia do Ambiente e Filosofia Política e pretende levar a cabo a análise do pensamento de Ulrich Beck, sociólogo alemão e autor da obra Risk Society. Partindo do conceito de Sociedade de Risco elaborado por Beck, tenta-se averiguar a forma como a presença do risco nas sociedades contemporâneas, sociedades industrialmente avançadas dominadas pela incerteza e pela insegurança devido à eclosão de desastres ambientais e tecnológicos de dimensão global e cujas efeitos não são totalmente previsíveis, conduziu a importantes alterações nas principais instâncias responsáveis pelo desenvolvimento do projecto da Modernidade - ciência, tecnologia e política -, provocando com isso um clima de descontinuidade e ruptura com os paradigmas fundamentais do pensamento moderno, nomeadamente com o seu paradigma tecnocientífico fundado no século XVII por Francis Bacon e Descartes, obrigando o momento actual da Modernidade a uma confrontação crítica com as consequências nocivas das suas inúmeras conquistas , algo que Beck designa como Modernidade Reflexiva. Perante ameaças de dimensão global, a solução para os problemas da Sociedade de Risco consiste num esforço de cooperação internacional a nível das instituições políticas. Nesse sentido, tenta-se averiguar, na segunda parte deste estudo, a forma como o Cosmopolitismo, como elemento primordial de uma nova cultura política em era de globalização, e a Europa, como modelo de instituições transnacionais, poderão contribuir para a resolução das diversas ameaças com que se confrontada a sociedade contemporânea.This dissertation has been made in the fields of Environmental Philosophy and Political Philosophy and intends to examine the thought of Ulrich Beck, German sociologist and author of the book entitled Risk Society. Taking the concept of Risk Society developed by Beck, we try to investigate the way the presence of risk in contemporary societies, industrially developed societies ruled by uncertainty and insecurity due to rising of environmental and technological threats of global scope and whose effects can't be totally predicted, has led to fundamental changes in the main authorities in charge of the project of Modernity science, technology and politics -, causing a breakthrough with the fundamental thesis of modern thought, mainly with its technocientific paradigm started in the 17th century by Francis Bacon and Descartes, compelling the present moment of Modernity to a critical confrontation with the harmful consequences of its countless victories, something that Beck calls Reflexive Modernization. In the presence of threats with a global scope, the solution to the problems of Risk Society can only be international cooperation on the level of political institutions. Being so, on the second part of this dissertation, we focus our attention in Cosmopolitanism, as an essential element of a new political culture in the age of globalization, and Europe, as a model of transnational institutions, can contribute to the solution of the several threats faced by contemporary society
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