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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Je švédský snus preventivní náhražkou cigaret? / Is Swedish snus a preventive substitute for cigarettes?

Oppoyen, Fredrik January 2010 (has links)
This is a review paper on the usage of smokeless tobacco, snus. A narrative view of published papers and other date sources (for example, internet-base information) on snus use, use of other tobacco products, and changes in health status in Sweden and Norway. The snus consumption have increased substantially during the recent decades and today more than every fifth male adult uses snus daily in Norway and Sweden. Some of the publications made from snus are written in Scandinavia, and therefore some of the papers are directly translated from Scandinavian into English. It must be emphasized that this is not a study on snus, rather a review paper. This text will shortly be about the dramatic increase in snus usage among adults in Scandinavia, mainly Sweden and Norway the last decade and their short and longterm effects. In the recent times the tobacco industry has been active in developing and marketing new products that might be perceived as less harmful to health than typical cigarettes. At the same time, there has been an increasingly vigorous debate within the public health community over the most appropriate response to the new products being developed by the industry. In this debate, public health advocates have been mindful of the historical precedents set by previous tobacco industry attempts to...
2

Risk Identification and Prevention in China’s Guarantee Industry

January 2016 (has links)
abstract: This study seeks to develop a framework that can help firms in China’s guarantee industry to better identify and prevent risk when they offer guarantee services to small and medium-sized enterprises (SME). With the continuously increasing demands of SME financing, the guarantee industry has developed rapidly in China. Meanwhile, the turmoil in global financial markets and the significant slowdown of global economy have started to have a negative impact on China’s economy, increasing the risk exposure of China’s guarantee industry. In this context, risk identification and prevention becomes the core competence of a guarantee company. Based on a review of the existing research, two in-depth case studies, and the author’s personal experiences in this industry, this paper does not only provide a comprehensive list of the risks that guarantee firms face in China but also measures for risk identification and prevention. This thesis is organized as follows. First, I provide a brief description about the emergence and development of China’s guarantee industry, as well as its current status. Next, I explain what kinds of risks faced by guarantee firms in China that influence their performance and survival, and summarize the various external and internal risk factors. I also conduct one in-depth case analysis to illustrate how a guarantee firm can better identify the risks it is exposed to. Next, on the basis of another in-depth case analysis, I develop a framework that can help guarantee firms to systematically develop effective measures of risk identification and prevention. I conclude with a discussion of this study’s implications for guarantee firms and the regulatory governmental agencies in China. / Dissertation/Thesis / Doctoral Dissertation Business Administration 2016
3

Les pratiques de jardinage face aux risques sanitaires et environnementaux des pesticides : les approches différenciées de la France et du Québec / The gardening practices in front of sanitary and environmental pesticides risks : the differentiated approaches of France and Québec

Barrault, Julia 21 September 2012 (has links)
La thèse met en évidence, dans le cas de la France, une forme de régulation composite des risques sanitaires et environnementaux liés aux usages des pesticides par les jardiniers amateurs, qui comporte trois principales dimensions. (1) Intimement articulée aux mécanismes de marché, cette forme de régulation impute l’essentiel de la responsabilité à l’utilisateur considéré en tant que consommateur à responsabiliser, alors que les autorités publiques considèrent les firmes de pesticides comme des opérateurs économiques dont les avantages compétitifs sont à valoriser, veillant donc à respecter la dynamique de l’offre et de la demande tout en se chargeant d’encadrer ce marché par l’homologation des produits. (2) Elle épouse les principes de la société singulariste où l’individu serait la référence centrale de la dynamique des sociétés contemporaines et le régulateur des problèmes collectifs par ses choix de consommation et ses prises de positions individuelles. (3) Elle s’opère dans un contexte où l’État a per¬du sa centralité sous la double influence de l’européanisation et de la décentralisation et où les modes de régulations politiques sont caractérisés par des formes moins dirigistes de gouvernement pouvant être définies comme des « politiques sans politique ». La régulation composite des pesticides domestiques est porteuse d’un postulat implicite qui impute la responsabilité des risques aux usagers et qui, si elle laisse ouverte la voie à une po¬ten-tielle réduction de l’usage des produits, tend à limiter leur exclusion et réduit les possibilités d’une transition vers un jardinage sans pesticides. / In 2008, the amount of pesticides used by amateur gardeners in the approximately fifteen million private gardens which exist in France and which represent a total area of a million hectares, rose to 3500 tons. Within the framework of a highly growing social awareness regarding health and environment problems and whilst the cut back on the use of pesticides in agriculture represents one of the main political objectives in the field of environmental protection, and Europe defines its chemical substances control policies (REACH), a study on the use of pesticides in gardening practices represents a good observation point to understand representations, dispositions and social practices linked to the use of pesticides in private gardens, to question the announced “greening” of life styles, to appreciate the capacity of the commercial production-distribution chain to manage such problems, and finally to evaluate the impact and direction of public policies to prevent health and environment risks.The results of the thesis are supported by sociological investigations carried out with amateur gardeners, by means of questionnaires (N=900) and interviews (N=24), with producers and distributors of phytosanitary products and with the press specialized in gardening (N=17) in France. The analysis of the pesticides code of management applied since 2003 in Quebec and which constitutes a regulation which prohibits the use and sale of a series of pesticides recognized as the most hazardous health-wise in municipal and private gardens, represents a counterpoint of the French situation.In the case of France, the thesis underlines a sort of composite regulation regarding the sanitary and environmental risks linked to the use of pesticides by amateur gardeners, involving three dimensions. (1) Intimately linked to the marketing mechanisms, this type of regulation attributes the core of the responsibility to the user, considered as the consumer to be blamed, while public authorities consider the firms which produce the pesticides as economic operators whose competitive advantages must be considered, seeking to respect the dynamics of offer and demand as well as controlling this market based on product certification. (2) It adopts the principles of the one-man society where the individual would be the main reference of the dynamics of contemporary societies and the regulator of collective problems based on his consumer choices and his individual position-taking. (3) It is located in a context where the State has lost its central position under the double influence of “Europeanization” and “decentralization” and where the types of political regulations are characterized by less interventionist forms of government, which can be defined as “politics without politics”. The composite regulation of domestic pesticides has an implicit postulate which attributes the responsibility of the risks involved to the users and which , in case of leaving an open door to the potential reduction of the use of products, tends to limit their exclusion as well as the possibilities of a transition towards pesticide free gardening.
4

La gestion du risque contractuel par le contrat : étude du droit français à la lumière du droit anglais / Managing contractual risk through the contract

Downe, Alexis 09 November 2018 (has links)
Si le contrat est un acte de prévision, il est également à l’origine de certains risques. Ces risques contractuels désignent l’éventualité d’un écart avec la réalisation de l’opération contractuelle. Lorsqu’ils sont pensés en corrélation avec la norme contractuelle, il est possible de classer les risques contractuels en trois selon qu’il s’agit de risques sémantiques, opérationnels ou financiers. Avant d’observer la marge de manœuvre des parties pour gérer ces risques, il faut délimiter la répartition par défaut desdits risques. Une telle répartition varie considérablement en fonction du type contractuel, de l’unilatéralisme du contrat-échange vers le partage dans le contrat-alliance en passant par l’équilibre des risques au sein des contrats-coopération. La gestion des risques par les parties repose sur le principe de liberté contractuelle, mais cette possibilité doit être plus ou moins encadrée selon la nature de la relation contractuelle. Par conséquent, il est possible de proposer un contrôle distinct pour les contrats d’adhésion et les contrats négociables. Toutefois, même valides, les clauses de gestion des risques contractuels sont limitées au stade de leur application que ce soit en raison de l’extinction du contrat ou du comportement des parties. / The contract is often thought of as an act of anticipation. However, it can also be viewed as the origin of certain risks. These contractual risks refer to the possibility of a discrepancy in achieving the completion of the contractual operation. When these risks are compared with the contractual norm, it is possible to classify them in three groups: semantic, operational and financial. Before studying how these risks can be managed by the parties, it is important to examine how the legal system allocates these risks by default. Such an allocation varies considerably from one contractual type to another. In exchange-contracts the risks are allocated unilaterally to one of the parties. Whereas in cooperation-contracts an equilibrium is sought, whilst in alliance-contracts the risks are shared. The possibility for parties to manage these risks rests upon the principle of freedom of contract. However, this possibility must be regulated depending on the nature of the contractual relationship. Therefore, regulation must be more severe in certain standard contracts and less intrusive in negociable contracts. Even when valid, certain risk-management clauses may be affected by external factors such as the extinction of the contract or the behaviour of the parties.
5

Educação em saúde na prevenção do risco gravídico pré-natal e interconcepcional / Health education to the prevention of prenatal and interconceptional risk

Candeias, Nelly Martins Ferreira 22 March 1979 (has links)
Este trabalho discute alguns aspectos de particular interesse para Educadores de Saúde Pública com o objetivo de aperfeiçoar o componente educativo de programas de saúde materno-infantil. Com vistas no diagnóstico educativo e para fins de análise estatística, dividiu-se a população amostral, constituída por 404 mulheres internadas no Serviço de ObstetrÍcia de um Hospital em São Paulo, Brasil, a partir dos seguintes critérios: mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez e mulheres que a iniciaram no terceiro trimestre da gravidez ou sem assistência pré-natal; mulheres com atitudes positivas e mulheres com atitudes negativas em relação à gravidez; mulheres cujos maridos ou companheiros demonstraram atitudes positivas e mulheres cujos maridos ou companheiros demonstraram atitudes negativas em relação à gravidez. Ao analisar as sub-amostras, procurou a Autora verificar se a proporção de mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez diferia significantemente da proporção de mulheres que iniciaram a assistência pré-natal no terceiro trimestre ou que não receberam assistência pré-natal. Nesta comparação consideraram-se as seguintes variáveis: idade, paridade, histórico, intervalo entre as gestações, renda per capita familiar, escolaridade, naturalidade, estado civil, risco gravídico e atitudes em relação à gravidez. Para avaliação do risco gravídico da população amostral, recorreu-se ao sistema de avaliação de Perkin. A análise estatística permitiu verificar que, no que concerne as variáveis doenças intercorrentes, intervalo entre gestações, estado civil e atitudes em relação à gravidez de mulheres casadas e de seus maridos, as diferenças nas proporções entre o grupo de mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez e o grupo de mulheres que iniciaram a assistência pré-natal no terceiro trimestre da gravidez ou que não receberam assistência pré-natal foram estatisticamente significantes. Compararam-se também mulheres com atitudes positivas e mulheres com atitudes negativas em relação à gravidez em termos das variáveis estado civil, idade, puridade e risco gravídico, tendo-se observado, nos dois grupos, diferenças de proporções estatisticamente significantes. Igualmente significante foi a diferença de proporções entre maridos com atitudes positivas e maridos com atitudes negativas em relação à gravidez de suas mulheres de acordo com o risco gravídico das mesmas. Não foi significante, entretanto, a diferença de proporção entre atitudes em relação à gravidez dos companheiros de mulheres solteiras e risco gravídico das mesmas. A Autora apresenta um Programa de Educação em Saúde a ser aplicado durante a assistência pré-natal e durante a internação, no período pós-parto. O conteúdo educativo do programa visa ao controle do risco gravídico no período natal e interconcepcional. / This paper discusses aspects of particular interest for Health Educators with the objectif of strenthening the educational component of maternal and child health programmes. With the purpose of educational diagnosis and statistical analysis, the study sample composed of 404 women hospitalized at the Obstetric Ward of a general Hospital in São Paulo, Brazil, was divided in the following subsamples: women who began prenatal care in the first and second trimesters of pregnancy and women who began in the last trimester of pregnancy along with women without prenatal care; women with positive attitudes and women with negative attitudes towards pregnancy: women whose husbands or \"companions\" showed positive attitudes and women whose husbands or \"companions\" showed negative attitudes. In analysing the subsamples, the Author tried to verify if the proportion of women that began the prenatal care in the first and second trimesters differed significantly from the proportion of women that began the prenatal care in the last trimester as well as with women without prenatal care. In this comparison the following variables were considered: age, parity, medical history, birth interval, family income, schooling, place of birth, marital status, reproductive risk and attitudes towards pregnancy. To assess the reproductive risk of the study group, Perkin\'s system of evaluation for identifying reproductive risk was used. Statistical analysis showed that there was a significant difference between proportions corresponding to women who began prenatal care in the first and second trimesters of pregnancy and those corresponding to women who began in the last trimester or received no attention at all in terms of the following variables: pathologic conditions, birth interval, marital status and attitudes towards pregnancy. Women with positive attitudes and those with negative attitudes towards pregnancy were compared in terms of marital status, age, parity and pregnancy risk. It was observed that there were statistically significant differences of proportions between the two groups. Equally significant was the difference of proportions between husbands with positive attitudes and husbands with negative attitudes towards the reproductive risk of their wives\' pregnancies. However, the differences between proportions corresponding to attitudes towards pregnancy were not statistically significant regarding \"companions\" of unmarried women and the reproductive risk of such women. A Health Education Programme to be applied during prenatal care and during hospitalization after child birth is presented. The educational content of the programme is centered around prevention and control of reproductive risk in the prenatal and interconceptional periods.
6

Educação em saúde na prevenção do risco gravídico pré-natal e interconcepcional / Health education to the prevention of prenatal and interconceptional risk

Nelly Martins Ferreira Candeias 22 March 1979 (has links)
Este trabalho discute alguns aspectos de particular interesse para Educadores de Saúde Pública com o objetivo de aperfeiçoar o componente educativo de programas de saúde materno-infantil. Com vistas no diagnóstico educativo e para fins de análise estatística, dividiu-se a população amostral, constituída por 404 mulheres internadas no Serviço de ObstetrÍcia de um Hospital em São Paulo, Brasil, a partir dos seguintes critérios: mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez e mulheres que a iniciaram no terceiro trimestre da gravidez ou sem assistência pré-natal; mulheres com atitudes positivas e mulheres com atitudes negativas em relação à gravidez; mulheres cujos maridos ou companheiros demonstraram atitudes positivas e mulheres cujos maridos ou companheiros demonstraram atitudes negativas em relação à gravidez. Ao analisar as sub-amostras, procurou a Autora verificar se a proporção de mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez diferia significantemente da proporção de mulheres que iniciaram a assistência pré-natal no terceiro trimestre ou que não receberam assistência pré-natal. Nesta comparação consideraram-se as seguintes variáveis: idade, paridade, histórico, intervalo entre as gestações, renda per capita familiar, escolaridade, naturalidade, estado civil, risco gravídico e atitudes em relação à gravidez. Para avaliação do risco gravídico da população amostral, recorreu-se ao sistema de avaliação de Perkin. A análise estatística permitiu verificar que, no que concerne as variáveis doenças intercorrentes, intervalo entre gestações, estado civil e atitudes em relação à gravidez de mulheres casadas e de seus maridos, as diferenças nas proporções entre o grupo de mulheres que iniciaram a assistência pré-natal no primeiro e segundo trimestres da gravidez e o grupo de mulheres que iniciaram a assistência pré-natal no terceiro trimestre da gravidez ou que não receberam assistência pré-natal foram estatisticamente significantes. Compararam-se também mulheres com atitudes positivas e mulheres com atitudes negativas em relação à gravidez em termos das variáveis estado civil, idade, puridade e risco gravídico, tendo-se observado, nos dois grupos, diferenças de proporções estatisticamente significantes. Igualmente significante foi a diferença de proporções entre maridos com atitudes positivas e maridos com atitudes negativas em relação à gravidez de suas mulheres de acordo com o risco gravídico das mesmas. Não foi significante, entretanto, a diferença de proporção entre atitudes em relação à gravidez dos companheiros de mulheres solteiras e risco gravídico das mesmas. A Autora apresenta um Programa de Educação em Saúde a ser aplicado durante a assistência pré-natal e durante a internação, no período pós-parto. O conteúdo educativo do programa visa ao controle do risco gravídico no período natal e interconcepcional. / This paper discusses aspects of particular interest for Health Educators with the objectif of strenthening the educational component of maternal and child health programmes. With the purpose of educational diagnosis and statistical analysis, the study sample composed of 404 women hospitalized at the Obstetric Ward of a general Hospital in São Paulo, Brazil, was divided in the following subsamples: women who began prenatal care in the first and second trimesters of pregnancy and women who began in the last trimester of pregnancy along with women without prenatal care; women with positive attitudes and women with negative attitudes towards pregnancy: women whose husbands or \"companions\" showed positive attitudes and women whose husbands or \"companions\" showed negative attitudes. In analysing the subsamples, the Author tried to verify if the proportion of women that began the prenatal care in the first and second trimesters differed significantly from the proportion of women that began the prenatal care in the last trimester as well as with women without prenatal care. In this comparison the following variables were considered: age, parity, medical history, birth interval, family income, schooling, place of birth, marital status, reproductive risk and attitudes towards pregnancy. To assess the reproductive risk of the study group, Perkin\'s system of evaluation for identifying reproductive risk was used. Statistical analysis showed that there was a significant difference between proportions corresponding to women who began prenatal care in the first and second trimesters of pregnancy and those corresponding to women who began in the last trimester or received no attention at all in terms of the following variables: pathologic conditions, birth interval, marital status and attitudes towards pregnancy. Women with positive attitudes and those with negative attitudes towards pregnancy were compared in terms of marital status, age, parity and pregnancy risk. It was observed that there were statistically significant differences of proportions between the two groups. Equally significant was the difference of proportions between husbands with positive attitudes and husbands with negative attitudes towards the reproductive risk of their wives\' pregnancies. However, the differences between proportions corresponding to attitudes towards pregnancy were not statistically significant regarding \"companions\" of unmarried women and the reproductive risk of such women. A Health Education Programme to be applied during prenatal care and during hospitalization after child birth is presented. The educational content of the programme is centered around prevention and control of reproductive risk in the prenatal and interconceptional periods.
7

On Risk Prevention and Supervision of Local Trading Platforms for Financial Assets

January 2017 (has links)
abstract: This dissertation focuses on risk prevention and regulatory issues of financial asset trading platforms, exploring the composition of a financial asset trading platform and its risks, formulating the general framework of platform risk prevention and regulation, and discussing the methodologies for monitoring and managing the risk of financial assets trading platform. The dissertation is divided into eight chapters. The first chapter is the introduction, which discusses the current status in this research field, the motivation and significance of the research topic. The second chapter discusses the transaction cost theory, information asymmetry theory, financial risk management theory, financial supervision theory and other related basic theories related to financial asset trading platform risk prevention and supervision. The third chapter presents the definition, the main types, the generating mechanism and the transmission mechanism of the financial asset trading platform. The fourth chapter elaborates theoretically on the general framework of financial asset trading platform risk prevention and supervision based on the aspects of basic principles, key tasks, applicable methods and constituent elements. The fifth chapter discusses the performance of financial asset trading business, asset return trading business, financing business and information coupling business on financial asset trading platforms, and analyzes the risk prevention of financial asset trading platforms from a business perspective. The sixth chapter discusses the development of financial asset trading platforms in developed countries, and summarizes the experience and practice of their risk prevention and supervision based on four categories of business lines. On this basis, the dissertation draws the inspiration and implications for the future development of the trading platforms in our country. The seventh chapter puts forward policy recommendations regarding risk prevention and supervision of financial asset trading platforms in five aspects: legal positioning, credit information system, protection of consumer rights, self-discipline management and business supervision. / Dissertation/Thesis / Doctoral Dissertation Business Administration 2017
8

"A AIDS ta no babado": concepções de risco e prevenção frente a epidemia do HIV/AIDS entre homossexuais da zona urbana de Senhor do Bonfim

Costa, José Hermógenes Moura da 29 August 2007 (has links)
Submitted by Oliveira Santos Dilzaná (dilznana@yahoo.com.br) on 2016-07-12T14:27:29Z No. of bitstreams: 1 dissertação de José Hermógenes Moura da Costa.pdf: 575660 bytes, checksum: 5ff33d69927a96d0d70ff9da05f10333 (MD5) / Approved for entry into archive by Oliveira Santos Dilzaná (dilznana@yahoo.com.br) on 2016-07-25T15:10:42Z (GMT) No. of bitstreams: 1 dissertação de José Hermógenes Moura da Costa.pdf: 575660 bytes, checksum: 5ff33d69927a96d0d70ff9da05f10333 (MD5) / Made available in DSpace on 2016-07-25T15:10:42Z (GMT). No. of bitstreams: 1 dissertação de José Hermógenes Moura da Costa.pdf: 575660 bytes, checksum: 5ff33d69927a96d0d70ff9da05f10333 (MD5) / Considerando o quadro de retomada ou estabilização do risco de infecção pelo HIV entre homens que fazem sexo com outros homens, e o concomitante processo de interiorização da epidemia da AIDS, o estudo pretendeu a problematização dos modos como os homossexuais de Senhor do Bonfim se orientam nas situações de interação sexual frente a epidemia. As noções êmicas de risco e prevenção são categorias chave. Os contextos e configurações das interações sexuais proporcionam a constituição de modalidades de prevenção muito próprias, atestando o quanto questões que envolvem o risco e a prevenção são concebidas sócioculturalmente uma vez que são negociadas nas diversas situações em que os sujeitos se engajam em relações sexuais. A prevenção é tomada enquanto uma construção cultural, portanto, não podendo ser estudada senão sob a visão do conjunto das representações da doença, do corpo, da infelicidade e do mundo no qual os indivíduos estão inseridos. Assim, a vivência do risco e mesmo a sua percepção não se restringem ao universo individual, ao contrário, o comportamento de risco é percebido e negociado na rede de relações sociais. Em última instância, ele é fruto das interações sociais. Considering the retaking picture or stabilization of the infection risk for HIV among men that make sex with other men, and the concomitant process of interiority of the epidemic of AIDS, the study intended the questioner of the manners as the homosexuals of Mister of Bonfim they are guided in the situations of interaction sexual front the epidemic. The notions risk and prevention are categories key. The contexts and configurations of the sexual interactions provide the constitution of very own prevention modalities, attesting him/it as subjects that involve the risk and the prevention are become pregnant partner-culturally once they are negotiated in the several situations in that the subjects are engaged in sexual relationships. The prevention is taken while a cultural construction, therefore, not could be studied except under the vision of the group of the representations of the disease, of the body, of the unhappiness and of the world in which the individuals are inserted. Like this, the existence of the risk and same his/her perception doesn't limit to the individual universe, to the opposite, the risk behavior is noticed and negotiated in the net of social relationships. Ultimately, he is fruit of the social interactions.
9

Prevence rizik při konstrukci základových stanic veřejné telekomunikační sítě / Risk prevention of the construction of public telecommunication network base stations

Smrž, Petr January 2013 (has links)
This master thesis consist of two parts, theoretical and practical part. The theoretical part of the thesis deals with the general description of the base stations of mobile public telecommunication networks, their structure, maintenance, construction and staff requirements. The practical part consists of performing an audit of the company in terms of risk prevention at base stations, audit evaluation and recommendation for improvement.
10

Safety-Bag pour les systèmes complexes / Safety-Bag for complex systems

Brini, Manel 23 November 2018 (has links)
Les véhicules automobiles autonomes sont des systèmes critiques. En effet, suite à leurs défaillances, ils peuvent provoquer des dégâts catastrophiques sur l'humain et sur l'environnement dans lequel ils opèrent. Le contrôle des véhicules autonomes robotisés est une fonction complexe, qui comporte de très nombreux modes de défaillances potentiels. Dans le cas de plateformes expérimentales qui n'ont suivi ni les méthodes de développement ni le cycle de certification requis pour les systèmes industriels, les probabilités de défaillances sont beaucoup plus importantes. En effet, ces véhicules expérimentaux se heurtent à deux problèmes qui entravent leur sûreté de fonctionnement, c'est-à-dire la confiance justifiée que l'on peut avoir dans leur comportement correct. Tout d'abord, ils sont utilisés dans des environnements ouverts, au contexte d'exécution très large. Ceci rend leur validation très complexe, puisque de nombreuses heures de test seraient nécessaires, sans garantie que toutes les fautes du système soient détectées puis corrigées. De plus, leur comportement est souvent très difficile à prédire ou à modéliser. Cela peut être dû à l'utilisation des logiciels d'intelligence artificielle pour résoudre des problèmes complexes comme la navigation ou la perception, mais aussi à la multiplicité de systèmes ou composants interagissant et compliquant le comportement du système final, par exemple en générant des comportements émergents. Une technique permettant d'augmenter la sécurité-innocuité (safety) de ces systèmes autonomes est la mise en place d'un composant indépendant de sécurité, appelé « Safety-Bag ». Ce système est intégré entre l'application de contrôle-commande et les actionneurs du véhicule, ce qui lui permet de vérifier en ligne un ensemble de nécessités de sécurité, qui sont des propriétés nécessaires pour assurer la sécurité-innocuité du système. Chaque nécessité de sécurité est composée d'une condition de déclenchement et d'une intervention de sécurité appliquée quand la condition de déclenchement est violée. Cette intervention consiste soit en une inhibition de sécurité qui empêche le système d'évoluer vers un état à risques, soit en une action de sécurité afin de remettre le véhicule autonome dans un état sûr. La définition des nécessités de sécurité doit suivre une méthode rigoureuse pour être systématique. Pour ce faire, nous avons réalisé dans nos travaux une étude de sûreté de fonctionnement basée sur deux méthodes de prévision des fautes : AMDEC (Analyse des Modes de Défaillances, leurs Effets et leur Criticité) et HazOp-UML (Etude de dangers et d'opérabilité) qui mettent l'accent respectivement sur les composants internes matériels et logiciels du système et sur l'environnement routier et le processus de conduite. Le résultat de ces analyses de risques est un ensemble d'exigences de sécurité. Une partie de ces exigences de sécurité peut être traduite en nécessités de sécurité implémentables et vérifiables par le Safety-Bag. D'autres ne le peuvent pas pour que le système Safety-Bag reste un composant relativement simple et validable. Ensuite, nous avons effectué des expérimentations basées sur l'injection de fautes afin de valider certaines nécessités de sécurité et évaluer le comportement de notre Safety-Bag. Ces expériences ont été faites sur notre véhicule robotisé de type Fluence dans notre laboratoire dans deux cadres différents, sur la piste réelle SEVILLE dans un premier temps et ensuite sur la piste virtuelle simulée par le logiciel Scanner Studio sur le banc VILAD. Le Safety-Bag reste une solution prometteuse mais partielle pour des véhicules autonomes industriels. Par contre, il répond à l'essentiel des besoins pour assurer la sécurité-innocuité des véhicules autonomes expérimentaux. / Autonomous automotive vehicles are critical systems. Indeed, following their failures, they can cause catastrophic damage to the human and the environment in which they operate. The control of autonomous vehicles is a complex function, with many potential failure modes. In the case of experimental platforms that have not followed either the development methods or the certification cycle required for industrial systems, the probabilities of failure are much greater. Indeed, these experimental vehicles face two problems that impede their dependability, which is the justified confidence that can be had in their correct behavior. First, they are used in open environment, with a very wide execution context. This makes their validation very complex, since many hours of testing would be necessary, with no guarantee that all faults in the system are detected and corrected. In addition, their behavior is often very difficult to predict or model. This may be due to the use of artificial intelligence software to solve complex problems such as navigation or perception, but also to the multiplicity of systems or components interacting and complicating the behavior of the final system, for example by generating behaviors emerging. A technique to increase the safety of these autonomous systems is the establishment of an Independent Safety Component, called "Safety-Bag". This system is integrated between the control application and the actuators of the vehicle, which allows it to check online a set of safety necessities, which are necessary properties to ensure the safety of the system. Each safety necessity is composed of a safety trigger condition and a safety intervention applied when the safety trigger condition is violated. This intervention consists of either a safety inhibition that prevents the system from moving to a risk state, or a safety action to return the autonomous vehicle to a safe state. The definition of safety necessities must follow a rigorous method to be systematic. To do this, we carried out in our work a study of dependability based on two fault prevention methods: FMEA and HazOp-UML, that respectively focus on the internal hardware and software components of the system and on the road environment and driving process. The result of these risk analyzes is a set of safety requirements. Some of these safety requirements can be translated into safety necessities, implementable and verifiable by the Safety-Bag. Others cannot be implemented in the Safety-Bag. The latter must remain simple so that it is easy to be validated. Then, we carried out experiments based on the faults injection in order to validate some safety necessities and to evaluate the Safety-Bag's behavior. These experiments were done on our robotic vehicle type Fluence in our laboratory in two different settings, on the actual track SEVILLE at first and then on the virtual track simulated by the Scanner Studio software on the VILAD testbed. The Safety-Bag remains a promising but partial solution for autonomous industrial vehicles. On the other hand, it meets the essential needs for the safety of experimental autonomous vehicles.

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