Reconnaissance des actions humaines à partir d'une séquence vidéo

The work done in this master's thesis, presents a new system for the recognition of human actions from a video sequence. The system uses, as input, a video sequence taken by a static camera. A binary segmentation method of the the video sequence is first achieved, by a learning algorithm, in order to detect and extract the different people from the background. To recognize an action, the system then exploits a set of prototypes generated from an MDS-based dimensionality reduction technique, from two different points of view in the video sequence. This dimensionality reduction technique, according to two different viewpoints, allows us to model each human action of the training base with a set of prototypes (supposed to be similar for each class) represented in a low dimensional non-linear space. The prototypes, extracted according to the two viewpoints, are fed to a $K$-NN classifier which allows us to identify the human action that takes place in the video sequence. The experiments of our model conducted on the Weizmann dataset of human actions provide interesting results compared to the other state-of-the art (and often more complicated) methods. These experiments show first the sensitivity of our model for each viewpoint and its effectiveness to recognize the different actions, with a variable but satisfactory recognition rate and also the results obtained by the fusion of these two points of view, which allows us to achieve a high performance recognition rate.

Mesurer l'apport unique de l'adhésion à la culture des gangs de rue à l'explication des conduites délinquantes chez les adolescents et les hommes contrevenants

L’apport disproportionné aux taux de criminalité des membres des gangs de rue est, nul doute, une proposition empirique robuste. De nombreuses études ont conclu que l’association aux gangs de rue est un facteur de risque supplémentaire à celui que constitue déjà la fréquentation de pairs délinquants au nombre des meilleurs prédicteurs de la délinquance avec les antécédents criminels et les traits antisociaux de la personnalité. Pourtant, la contribution spécifique de l’association aux gangs de rue à l’explication de la délinquance est largement méconnue. Au nombre des variables les plus souvent citées pour l’expliquer figure néanmoins le concept de l’adhésion à la culture de gang qui n’a toutefois jamais été spécifiquement opérationnalisé. Le but de la thèse est d’étudier la contribution spécifique de l’adhésion d’un contrevenant à la culture des gangs de rue à l’explication de la délinquance. Plus précisément, elle a comme objectifs de définir la culture des gangs de rue, d’opérationnaliser l’adhésion à la culture des gangs de rue, d’examiner la fidélité de la mesure de l’adhésion à la culture de gang et d’étudier sa relation avec la nature, la variété et la fréquence des conduites délinquantes de contrevenants placés sous la responsabilité des centres jeunesse et des services correctionnels du Québec. Trois articles scientifiques, auxquels un chapitre régulier est joint, ont servi la démonstration de la thèse. D’abord, le premier article présente les démarches relatives au développement de la première Mesure de l’adhésion à la culture de gang, la MACg. Plus précisément, l’article présente la recension des écrits qui a permis de proposer une première définition de la culture de gang et d’opérationnaliser le concept. Il fait aussi état de la démarche de la validation de la pertinence de son contenu et des données préliminaires qui révèlent la très bonne cohérence interne de la MACg. Cette première étude est suivie de la présentation, dans le cadre d’un chapitre régulier, des résultats de l’examen de la cotation des principaux indicateurs de la culture de gang. Cette démarche constitue un complément nécessaire à l’examen de la validité apparente de la MACg. Les résultats révèlent des degrés de concordance très satisfaisants entre les observations de divers professionnels des centres jeunesse et des services correctionnels du Québec qui ont été invités à coter les indicateurs de la culture de gang à partir de deux histoires fictives d’un contrevenant mineur et d’un second d’âge adulte. Puis, le deuxième article présente les résultats d’un premier examen de la fidélité de la MACg à l’aide du modèle de Rasch de la Théorie de la réponse aux items. Ses résultats soutiennent l’unidimensionnalité de la MACg et sa capacité à distinguer des groupes d’items et de personnes le long d’un continuum de gravité d’adhésion à la culture de gang. Par contre, le fonctionnement différentiel et le mauvais ajustement de certains items sont observés, ainsi que l’inadéquation de la structure de réponses aux items (de type Likert) privilégiée lors de l’élaboration de la MACg. Une version réaménagée de cette dernière est donc proposée. Enfin, le troisième et dernier article présente les résultats de l’examen de la relation entre la délinquance et l’adhésion d’un contrevenant à la culture de gang telle que mesurée par la MACg. Les résultats soutiennent l’apport unique de l’adhésion d’un contrevenant à la culture de gang à la diversité et à la fréquence des conduites délinquantes auto-rapportées par des contrevenants placés sous la responsabilité des centres jeunesse et des services correctionnels du Québec. Le score à l’échelle originale et réaménagée de la MACg s’avère, d’ailleurs, un facteur explicatif plus puissant que l’âge, la précocité criminelle, les pairs délinquants et la psychopathie au nombre des meilleurs prédicteurs de la délinquance. L’étude met aussi en lumière l’étroite relation entre une forte adhésion à la culture de gang et la présence marquée de traits psychopathiques annonciatrice de problèmes particulièrement sérieux. Malgré ses limites, la thèse contribuera significativement aux développements des bases d’un nouveau modèle explicatif de l’influence de l’association aux gangs de rue sur les conduites des personnes. La MACg pourra aussi servir à l’évaluation des risques des hommes contrevenants placés sous la responsabilité du système de justice pénale et à l’amélioration de la qualité des interventions qui leur sont dédiées.

Neurotransmitters Functional Balance in Neurodegenerative Disease Management:recent Advances

The recent developments in neurobiology have rendered new prominence and potential to study about the structure and function of brain and related disorders. Human behaviour is the net result of neural control of the communication between brain cells. Neurotransmitters are chemicals that are used to relay, amplify and modulate electrical signals between neurons and/or another cell. It mediates rapid intercellular communication through the nervous system by interacting with cell surface receptors. These receptors often trigger second messenger signaling pathways that regulate the activity of ion channels. The functional balance of different neurotransmitters such as Acetylcholine (Ach), Dopamine (DA), Serotonin (5-HT), Norepinephrine (NE), Epinephrine (EPI), Glutamate and Gamma amino butyric acid (GABA) regulates the growth, division and other vital functions of a normal cell / organism (Sudha, 1998). Any change in neurotransmitters' functional balance will result in the failure of cell function and may lead to the occurrence of diseases. Abnormalities in the production or functioning of neurotransmitters have been implicated in a number of neurological disorders like Schizophrenia, Alzheimer's, Epilepsy, Depression and Parkinson's disease. Changes in central and peripheral neuronal signaling system is also noted in diabetes, cancer, cell proliferation, alcoholism and aging. Elucidation of neurotransmitters receptor interaction pathways and gene expression regulation by second messengers and transcriptional factors in health and disease conditions can lead to new small molecules for development of therapeutic agents to improve neurological disease conditions. Increased awareness of the global effects of neurological disorders should help health care planners and the neurological community set appropriate priorities in research, prevention, and management of these diseases.

Development of Total Quality Management System in Seafood (Freezing) Industry in Kerala

Quality related problems have become dominant in the seafood processing industry in Kerala. This has resulted in the rejection of seafood sent from India to many destinations. The latest being the total block listing of seafood companies from India from being exported to Europe and partial block listing by the US. The quality systems prevailed in the seafood industry in India were outdated and no longer in use in the developed world. According to EC Directive discussed above all the seafood factories exporting to European countries have to adopt HACCP. Based on this, EIA has now made HACCP system mandatory in all the seafood processing factories in India. This transformation from a traditional product based inspection system to a process control system requires thorough changes in the various stages of production and quality management. This study is conducted by the author with to study the status of the existing infrastructure and quality control system in the seafood industry in Kerala with reference to the recent developments in the quality concepts in international markets and study the drawbacks, if any, of the existing quality management systems in force in the seafood factories in Kerala for introducing the mandatory HACCP concept. To assess the possibilities of introducing Total Quality Management system in the seafood industry in Kerala in order to effectively adopt the HACCP concept. This is also aimed at improving the quality of the products and productivity of the industry by sustaining the world markets in the long run.

Hans Jürgen Eysenck. Life and work of one of the most infl uential scientist in the history of psychology

On this article, the biography and work of one of the most influential scientists in psychology history is briefl y introduced. With his work, he laid the bases for the scientific study not only on personality, but also on human behaviour. Hence, the most important contributions done by this author are highlighted in a wide range of areas of our discipline, as well as the vision he had about how psychology should be as a science. A series of considerations related to the current situation of scientific psychology in Argentina, lead us to the conclusion that it is essential to rescue his work from forgetfulness, apart from going back over some of his lines of research and thoughts. 

Alteraciones en el material genético de pintores de carros expuestos a solventes orgánicos en una localidad de Bogotá

Los solventes orgánicos son sustancias químicas que por sus propiedades físico-químicas son fácilmente inhalados o absorbidos por la piel, pueden causar daños de diversa índole en la salud. En Colombia existen normas que contemplan las medidas de protección, sin embargo persiste la informalidad en el sector de pintores de autos, por lo cual los trabajadores expuestos, a largo plazo pueden ver afectada su salud. En este estudio se analizó la relación entre individuos expuestos laboralmente a los solventes orgánicos versus no expuestos con respecto a la longitud de sus telómeros y formación de fragilidades. Se emplearon muestras de sangre extraídas por venopunción, recolectada en dos tubos: uno con Heparina, destinado al cultivo de linfocitos, para obtener cromosomas metafásicos y evaluar en ellos la presencia de fragilidades; el otro tubo con EDTA, fue empleado para la extracción de ADN y se utilizó para obtener los valores de longitud telomérica mediante la técnica de PCR cuantitativa. Los análisis estadísticos se realizaron aplicando la prueba de rangos de Wilcoxon, en el caso de la presencia de fragilidades se analizó la razón No.Fragilidades/No.Metafases, aplicando el método de Wilcoxon se encontró que existe diferencia estadísticamente significativa entre expuestos y no expuestos (p = 0,036), en donde los expuestos presentan mayor frecuencia de fragilidades. Por otra parte el valor relativo de longitud telomérica del grupo de expuestos fue mayor que el observado en el grupo de no expuestos, esta diferencia fue estadísticamente significativa (Wilcoxon, p = 0.002).

Annual textural banding in Holocene estuarine silts, Severn Estuary Levels (SW Britain): patterns, cause and implications

A high-resolution textural study has been made of laminated and banded estuarine silts exposed intertidally at representative localities and horizons in the Holocene deposits of the Severn Estuary Levels. The laminae, on a submillimetre to millimetre scale, are sharp-based, graded couplets formed of a lower silty part overlain by a finer-textured clayey element. The centimetre- to decimetre-scale banding is formed of laminae in alternating, gradually intergrading sets of relatively coarse and relative fine-grained examples. At outcrop in the field, the banding is recognizable because the coarse sets prove to be recessive to varying degrees under the influence of weathering and current action. Independent evidence at two localities points toward an annual origin for the banding; at a third it arose during part of what appears to have been a relatively short period. Quantified physical arguments suggest that the textural banding is a response of suspended fine sediment to marked seasonal changes in sea temperature and windiness. The banded silts occur in four distinct stratigraphical contexts and record high deposition rates (order 0.01-0.1 m/yr). Because physical factors determine their textures, the silts potentially afford insights in all contexts into aspects of changing Holocene climatic conditions. In one context, the thickness of the bands points to high (order 0.01-0.1 m/yr) but comparatively short-lived (order 10s-100s yrs) rates of relative water-level rise. In the others, however, the banding has no implications for sea-level behaviour, and simply records gross environmental disequilibrium, for example, the recovery of mudflats/marshes after an erosional episode. Similarly, because on account of their rapid accumulation the banded silts preserve animal and human tracks and trackways especially well, they provide an archive of animal and human behaviour in the area during the Holocene.

A little learning is a dangerous thing: an experimental demonstration of ignorance-driven inference

Studies of ignorance-driven decision making have been employed to analyse when ignorance should prove advantageous on theoretical grounds or else they have been employed to examine whether human behaviour is consistent with an ignorance-driven inference strategy (e. g., the recognition heuristic). In the current study we examine whether-under conditions where such inferences might be expected-the advantages that theoretical analyses predict are evident in human performance data. A single experiment shows that, when asked to make relative wealth judgements, participants reliably use recognition as a basis for their judgements. Their wealth judgements under these conditions are reliably more accurate when some of the target names are unknown than when participants recognize all of the names (a "less-is-more effect"). These results are consistent across a number of variations: the number of options given to participants and the nature of the wealth judgement. A basic model of recognition-based inference predicts these effects.

Urban climates and global climate change

Cities and global climate change are closely linked: cities are where the bulk of greenhouse gas emissions take place through the consumption of fossil fuels; they are where an increasing proportion of the world’s people live; and they also generate their own climate – commonly characterized by the urban heat island. In this way, understanding the way cities affect the cycling of energy, water, and carbon to create an urban climate is a key element of climate mitigation and adaptation strategies, especially in the context of rising global temperatures and deteriorating air quality in many cities. As climate models resolve finer spatial-scales, they will need to represent those areas in which more than 50% of the world’s population already live to provide climate projections that are of greater use to planning and decision-making. Finally, many of the processes that are instrumental in determining urban climate are the same factors leading to global anthropogenic climate change, namely regional-scale land-use changes; increased energy use; and increased emissions of climatically-relevant atmospheric constituents. Cities are therefore both a case study for understanding, and an agent in mitigating, anthropogenic climate change. This chapter reviews and summarizes the current state of understanding of the physical basis of urban climates, as well as our ability to represent these in models. We argue that addressing the challenges of managing urban environments in a changing climate requires understanding the energy, water, and carbon balances for an urban landscape and, importantly, their interactions and feedbacks, together with their links to human behaviour and controls. We conclude with some suggestions for where further research is needed.

Effects of action observation on corticospinal excitability: muscle specificity, direction, and timing of the mirror response

Many human behaviours and pathologies have been attributed to the putative mirror neuron system, a neural system that is active during both the observation and execution of actions. While there are now a very large number of papers on the mirror neuron system, variations in the methods and analyses employed by researchers mean that the basic characteristics of the mirror response are not clear. This review focuses on three important aspects of the mirror response, as measured by modulations in corticospinal excitability: (1) muscle specificity, (2) direction, and (3) timing of modulation. We focus mainly on electromyographic (EMG) data gathered following single-pulse transcranial magnetic stimulation (TMS), because this method provides precise information regarding these three aspects of the response. Data from paired-pulse TMS paradigms and peripheral nerve stimulation (PNS) are also considered when we discuss the possible mechanisms underlying the mirror response. In this systematic review of the literature, we examine the findings of 85 TMS and PNS studies of the human mirror response, and consider the limitations and advantages of the different methodological approaches these have adopted in relation to discrepancies between their findings. We conclude by proposing a testable model of how action observation modulates corticospinal excitability in humans. Specifically, we propose that action observation elicits an early, non-specific facilitation of corticospinal excitability (at around 90 ms from action onset), followed by a later modulation of activity specific to the muscles involved in the observed action (from around 200 ms). Testing this model will greatly advance our understanding of the mirror mechanism and provide a more stable grounding on which to base inferences about its role in human behaviour.

North Sea archaeologies

North Sea Archaeologies traces the way people engaged with the North Sea from the end of the last ice age, around 10,000 BC, to the close of the Middle Ages, about AD 1500, drawing upon archaeological research from many countries, including the UK, Netherlands, Germany, Denmark, Sweden, Norway, Belgium, and France. It addresses topics which include the first interactions of people with the emerging North Sea, the origin and development of fishing, the creation of coastal landscapes, the importance of islands and archipelagos, the development of seafaring ships and their use by early seafarers and pirates, and the treatment of boats and ships at the end of their useful lives. The study offers a ‘maritime turn’ in Archaeology through the investigation of aspects of human behaviour that have been, to various extents, disregarded, overlooked, or ignored in archaeological studies of the land. The study concludes that the relationship between humans and the sea challenges the frequently invoked dichotomy between pre-modernity and modernity, since many ancient beliefs, superstitions, and practices linked to seafaring and engagement with the sea are still widespread in the modern era.

North Sea archaeologies: a maritime biography, 10,000 BC - AD 1500

North Sea Archaeologies traces the way people engaged with the North Sea from the end of the last ice age, around 10,000 BC, to the close of the Middle Ages, about AD 1500, drawing upon archaeological research from many countries, including the UK, Netherlands, Germany, Denmark, Sweden, Norway, Belgium, and France. It addresses topics which include the first interactions of people with the emerging North Sea, the origin and development of fishing, the creation of coastal landscapes, the importance of islands and archipelagos, the development of seafaring ships and their use by early seafarers and pirates, and the treatment of boats and ships at the end of their useful lives. The study offers a ‘maritime turn’ in Archaeology through the investigation of aspects of human behaviour that have been, to various extents, disregarded, overlooked, or ignored in archaeological studies of the land. The study concludes that the relationship between humans and the sea challenges the frequently invoked dichotomy between pre-modernity and modernity, since many ancient beliefs, superstitions, and practices linked to seafaring and engagement with the sea are still widespread in the modern era.

Should system dynamics be described as a 'hard' or 'deterministic' systems approach?

This paper explores the criticism that system dynamics is a ‘hard’ or ‘deterministic’ systems approach. This criticism is seen to have four interpretations and each is addressed from the perspectives of social theory and systems science. Firstly, system dynamics is shown to offer not prophecies but Popperian predictions. Secondly, it is shown to involve the view that system structure only partially, not fully, determines human behaviour. Thirdly, the field's assumptions are shown not to constitute a grand content theory—though its structural theory and its attachment to the notion of causality in social systems are acknowledged. Finally, system dynamics is shown to be significantly different from systems engineering. The paper concludes that such confusions have arisen partially because of limited communication at the theoretical level from within the system dynamics community but also because of imperfect command of the available literature on the part of external commentators. Improved communication on theoretical issues is encouraged, though it is observed that system dynamics will continue to justify its assumptions primarily from the point of view of practical problem solving. The answer to the question in the paper's title is therefore: on balance, no.

PETS 2014: dataset and challenge

This paper describes the dataset and vision challenges that form part of the PETS 2014 workshop. The datasets are multisensor sequences containing different activities around a parked vehicle in a parking lot. The dataset scenarios were filmed from multiple cameras mounted on the vehicle itself and involve multiple actors. In PETS2014 workshop, 22 acted scenarios are provided of abnormal behaviour around the parked vehicle. The aim in PETS 2014 is to provide a standard benchmark that indicates how detection, tracking, abnormality and behaviour analysis systems perform against a common database. The dataset specifically addresses several vision challenges corresponding to different steps in a video understanding system: Low-Level Video Analysis (object detection and tracking), Mid-Level Video Analysis (‘simple’ event detection: the behaviour recognition of a single actor) and High-Level Video Analysis (‘complex’ event detection: the behaviour and interaction recognition of several actors).

Simple Question, Complex Answer : Pathways Towards a 50% Decrease in Building Energy Use

Addressing building energy use is a pressing issue for building sector decision makers across Europe. In Sweden, some regions have adopted a target of reducing energy use in buildings by 50% until 2050. However, building codes currently do not support as ambitious objectives as these, and novel approaches to addressing energy use in buildings from a regional perspective are called for. The purpose of this licentiate thesis was to provide a deeper understanding of most relevant issues with regard to energy use in buildings from a broad perspective and to suggest pathways towards reaching the long-term savings objective. Current trends in building sector structure and energy use point to detached houses constructed before 1981 playing a key role in the energy transition, especially in the rural areas of Sweden. In the Swedish county of Dalarna, which was used as a study area in this thesis, these houses account for almost 70% of the residential heating demand. Building energy simulations of eight sample houses from county show that there is considerable techno-economic potential for energy savings in these houses, but not quite enough to reach the 50% savings objective. Two case studies from rural Sweden show that savings well beyond 50% are achievable, both when access to capital and use of high technology are granted and when they are not. However, on a broader scale both direct and indirect rebound effects will have to be expected, which calls for more refined approaches to energy savings. Furthermore, research has shown that the techno-economic potential is in fact never realised, not even in the most well-designed intervention programmes, due to the inherent complexity of human behaviour with respect to energy use. This is not taken account of in neither current nor previous Swedish energy use legislation. Therefore an approach that considers the technical prerequisites, economic aspects and the perspective of the many home owners, based on Community-Based Social Marketing methodology, is suggested as a way forward towards reaching the energy savings target.