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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.
31

Systemsäkerhetsarbete för forsknings- och försöksverksamhet inom Försvarsmaktens dykeri

Glashoff, Sofia January 2023 (has links)
För att möjliggöra teknisk vidareutveckling och forskning krävs i många fall framtagning av nya system eller produkter som ännu inte finns på marknaden. De säkerhetsrisker som uppkommer vid nyutveckling av system eller produkter bör åtgärdas innan de tas i bruk. Inom Försvarsmakten (FM) utförs detta genom ett systemsäkerhetsarbete. Ett systemsäkerhetsarbete syftar till att systemet eller produkten genomgår en systematisk process för att uppnå de säkerhetskrav och tolerabla risknivåer som finns inom organisationen. Denna rapport undersöker hur ett systemsäkerhetsarbete kan appliceras på forsknings- och försöksuppställningar inom dykeri på Försvarsmaktens Dykeri och Navalmedicinska Centrum (FM DNC) i Karlskrona. Arbetet syftar till att undersöka den uppdaterade processen enligt den nya versionen av Handbok i Systemsäkerhet, utgiven år 2022. Vidare syftar arbetet till att undersöka hur handbokens process kan tillämpas på forsknings- och försöksuppställningar. I arbetet används systemet Inertgas Utvädringsmaskin (IGUM) som ett exempel för att ta fram en lämplig process i syfte att få systemet godkänt för användning inom forskning. I arbetet undersöks även om ett systemsäkerhetsarbete kan effektiviseras genom att ta fram en mer standardiserad process för denna typ av verksamhet. Arbetets metod består av fyra olika delar: Litteraturstudier, intervjuer, en kurs samt handledning. Genom att kombinera information, tagen från litteraturen, med inhämtade svar på specifika frågor till experter inom ämnet kunde ett resultat tas fram. Resultatet innefattar tre exemplifierade processmetoder, beroende på systemets eller produktens användningsområde, samt hur ett systemsäkerhetsarbete kan effektiviseras. De tre processmetoderna som presenteras utgår ifrån handboken samt en kombination mellan Regler för Militär Sjöfart Dyk (RMS-Dyk) och Handlingsregel 05 (HR 05), såväl som de svar som gavs under intervjuerna. I nutid finns ännu ingen etablerad kunskap i hur ett systemsäkerhetsarbete ska utföras på forsknings- och försöksuppställningar inom FM:s dykeri, vilket gör arbetet till en viktig tillgång för den fortsatta utvecklingen. Detta gynnar inte bara personal inom organisationen, utan även samhället, då det ökar möjligheten till vidareutveckling och forskning. / To enable further technical development and research, developing new systems or products that are not yet available on the market is often necessary. The safety risks that arise with newly developed systems or products should be addressed before they are put into use, which is done through system safety work within the Swedish Armed Forces (FM). System safety work aims for the system or product to undergo a systematic process to achieve the organization's safety requirements and tolerable risk levels. This report examines how system safety work can be applied to research and test setups in diving at the Swedish Armed Forces Diving and Naval Medicine Center (FM DNC) in Karlskrona. The work aims to examine the updated process according to the new version of the System Safety Handbook, published year 2022, and to apply it to research and experimental setups. The report uses the Inert Gas Utvädringsmaskin (IGUM) system as an example to be able to develop a suitable process with the aim of getting the system approved for research purposes. The report also examines whether system safety work can be made more efficient by developing a more standardized process. The method consists of four parts: Literature studies, interviews, a course, and supervision. By combining information from the literature with answers gathered from the interviews, a result was found. The outcome includes three exemplified process methods, depending on the system or product's area of use, as well as how system safety work can be made more efficient. The three process methods presented are based on the handbook and a combination of Regler för Militär Sjöfart Dyk (RMS-Dyk) and Handlingsregel 05 (HR 05), as well as the answers given during the interviews. Currently, there is still no established knowledge of how system safety work should be done on research and test setups within the Swedish Armed Forces diving operations, which makes the report an asset for further development within this field. This not only benefits personnel within the organization but also the society, as there is an opportunity for further development and research.
32

Formalisation de la cohérence et calcul des séquences de coupe minimales pour les systèmes binaires dynamiques et réparables / Formal definition of coherency and computation of minimal cut sequences for binary dynamic and repairable systems

Chaux, Pierre-Yves 15 April 2013 (has links)
L'analyse prévisionnelle des risques d'un système complexe repose aujourd'hui sur une modélisation de la dynamique du système vis-à-vis des défaillances et réparations de ses composants. L'analyse qualitative d'un tel système consiste à rechercher et à analyser les scénarios conduisant à la panne. En raison de leur nombre, il est courant de ne s'intéresser qu'aux scénarios les plus caractéristiques, les Séquences de Coupe Minimales (SCM). L'absence de formalisation de ces SCM a généré soit des définitions spécifiques à certains outils de modélisation soit des définitions informelles. Les travaux présentés dans cette thèse proposent: i) un cadre et une définition formelle des séquences de coupe minimales, tout deux indépendants de l'outil de modélisation de fiabilité utilisé, ii) une méthode permettant leur calcul, méthode basée sur des propriétés déduites de leur définition, iii) l'extension des premières définitions aux composants multimodes. Ce cadre permet le calcul des SCM pour des installations décrites avec les Boolean logic Driven Markov Processes (BDMP). Sous l'hypothèse que l'ensemble des scénarios représentés implicitement via le modèle de sûreté établi peut être modélisé à l'aide d'un automate fini, ces travaux définissent la notion de cohérence des systèmes dynamiques et réparables, et le moyen d'obtenir une représentation minimale de l'ensemble des scénarios menant à la défaillance du système. / Preventive risk assessment of a complex system rely on a dynamic models which describe the link between the system failure and the scenarios of failure and repair events from its components. The qualitative analyses of a binary dynamic and repairable system is aiming at computing and analyse the scenarios that lead to the system failure. Since such systems describe a large set of those, only the most representative ones, called Minimal Cut Sequences (MCS), are of interest for the safety engineer. The lack of a formal definition for the MCS has generated multiple definitions either specific to a given model (and thus not generic) or informal. This work proposes i) a formal framework and definition for the MCS while staying independent of the reliability model used, ii) the methodology to compute them using property extracted from their formal definition, iii) an extension of the formal framework for multi-states components in order to perform the qualitative analyses of Boolean logic Driven Markov Processes (BDMP) models. Under the hypothesis that the scenarios implicitly described by any reliability model can always be represented by a finite automaton, this work is defining the coherency for dynamic and repairable systems as the way to give a minimal representation of all scenarios that are leading to the system failure.
33

Development of an intelligent e-commerce assurance model to promote trust in online shopping environment

Mayayise, Thembekile Olivia 01 1900 (has links)
Electronic commerce (e-commerce) markets provide benefits for both buyers and sellers; however, because of cyber security risks consumers are reluctant to transact online. Trust in e-commerce is paramount for adoption. Trust as a subject for research has been a term considered in depth by numerous researchers in various fields of study, including psychology and information technology. Various models have been developed in e-commerce to alleviate consumer fears, thus promoting trust in online environments. Third-party web seals and online scanning tools are some of the existing models used in e-commerce environments, but they have some deficiencies, e.g. failure to incorporate compliance, which need to be addressed. This research proposes an e-commerce assurance model for safe online shopping. The machine learning model is called the Page ranking analytical hierarchy process (PRAHP). PRAHP builds complementary strengths of the analytical hierarchy process (AHP) and Page ranking (PR) techniques to evaluate the trustworthiness of web attributes. The attributes that are assessed are Adaptive legislation, Adaptive International Organisation for Standardisation Standards, Availability, Policy and Advanced Security login. The attributes were selected based on the literature reviewed from accredited journals and some of the reputable e-commerce websites. PRAHP’s paradigms were evaluated extensively through detailed experiments on business-to-business, business-to-consumer, cloud-based and general e-commerce websites. The results of the assessments were validated by customer inputs regarding the website. The reliability and robustness of PRAHP was tested by varying the damping factor and the inbound links. In all the experiments, the results revealed that the model provides reliable results to guide customers in making informed purchasing decisions. The research also reveals hidden e-commerce topics that have not received attention, which generates knowledge and opens research questions for future researchers. These ultimately made significant contributions in e-commerce assurance, in areas such as security and compliance through the fusing of AHP and PR, integrated into a decision table for alleviating trustworthiness anxiety in various e-commerce transacting partners, e-commerce platforms and markets. / College of Engineering, Science and Technology / D. Phil. Information Systems
34

Outiller la conception centrée utilisateur en milieu industriel complexe : des techniques de traitement automatique de textes pour la conception des cockpits / Create tools for user centred design in a highly complex environment : automatic text analysis for cockpit design

Papaïx, Benoît 20 December 2011 (has links)
Dans le milieu aéronautique professionnel (un des secteurs professionnels les plus sûr au monde), la gestion des conséquences des erreurs humaines doit être améliorée pour garantir une sécurité maximum. Pour ce faire, il est nécessaire de mettre en place des techniques de conception centrées sur l’utilisateur. Cependant, la mise en place de ces techniques est rendue difficile par les particularités des systèmes sociotechniques complexes (la certification, la complexité des systèmes conçus, le nombre de personnes impliquées…). Notre étude a pour but de développer et de valider des outils d’aide à la conception centrée sur l’utilisateur, notamment pour le traitement automatique de grande quantité de données. Pour ce faire, nous avons, dans un premier temps, réalisé une étude basée sur le jugement d’expert visant à identifier, dans une base de données, des scenarii susceptibles de contenir une erreur de l’équipage. Les résultats de cette méthode par jugement d’expert ont été comparés à ceux obtenus à l’aide d’outils de traitement automatique. Cette comparaison a permis :1/ D’identifier des algorithmes pertinents pour l’extraction d’information dans des bases de données (algorithme des plus proches voisins et de filtrage bayesien) ;2/ De proposer une méthodologie permettant l’extraction automatique de situations à risque pouvant donner lieu à des études plus approfondies, sur simulateur par exemple. Cette étape est primordiale dans cadre de la conception centrée utilisateur.Les liens établis avec les études des incidents/accidents laissent envisager des impacts positifs sur la sécurité aérienne. / In the professional aeronautical field (one of the safest in the world), human error management must be improved to reach a better safety level. To do this, a user centred design process has to be implemented. However, due to the complexity of socio technical systems, the implementation of an efficient user centred design process could be challenging. To ease this process, our study aims to develop and validate specific tools, particularly for processing large amounts of textual data. In our study, we will firstly undertake an extraction of scenarios that can contain human errors in a specific database. This extraction will be based on expert judgment (control condition). Secondly, we will confront the control condition with results obtained automatically. The results of this comparison allow:1/ The identification of relevant algorithms for automatic information extraction within large textual databases (Nearest Neighbour, Bayesian filtering);2/ The identification of a methodology to extract risk situations that could be included in specific studies. This step is very important for the user centred design process.Links that we have established between our results and incident/accident studies allow us to consider positive impacts on aviation safety.
35

Katalog der Risiken - Risiken und ihre Darstellung

Proske, Dirk 24 September 2008 (has links)
Die Welt wird beherrscht durch Veränderung. Von den kleinsten Elementarteilchen bis zu den größten Galaxien kann man ein Entstehen und Vergehen beobachten. Diese Regel schließt auch die lebende Materie mit ein. Wir sehen Bäume wachsen oder das Getreide auf den Feldern reifen und wir müssen erkennen, daß auch wir, die Menschen, diesem Gesetz der Veränderung, dieser Vergänglichkeit unterliegen....
36

Tool Integration and Safety : A Foundation for Analysing the Impact of Tool Integrationon Non-functional Properties

Asplund, Fredrik January 2012 (has links)
The increasing complexity of embedded systems development is becoming difficult to handle with development environments based on disjoint engineering tools. Support for interactions between various engineering tools, especially through automated means, has therefore received an increased amount of attention during the last few years. The subsequent increase in the amount of tool integration is leading to an increased impact of tool integration on non-functional properties of development efforts, development environments and end products. At the same time there is a lack of methods and tools for analysing the relationship between these properties and tool integration. To establish a foundation for analysing this generic relationship, the specific relationship between tool integration and the safety of end products is analysed in this thesis. A survey was conducted to analyze the State of the Art of tool integration as related to safety. This survey specifically identified the lack of an efficient handling of tool integration by modern safety standards as an important concern. In relation to this survey, three theories were identified as of specific importance. These are the school of thought known as Systems Thinking, the Systems-Theoretic Accident Model and Processes (STAMP) causality model and the System-Theoretic Process Analysis (STPA) hazard analysis technique. Building on these theories, this thesis provides original contributions intended to (1) describe concepts and models related to tool integration and safety (the first and second contribution), (2) link tool integration to safety in a way that reduces complexity during analysis (the third contribution) and (3) propose how to interpret and make use of the implications of the presented theories and the first three contributions (the fourth and fifth contribution). • The first contribution is a new conceptual model of a development effort that emphasizes tool integration. • The second contribution is a new reference model for tool integration in highly heterogeneous environments. • The third contribution consists of nine safety-related tool chain properties, i.e. properties of tool chains that could mitigate at least part of the risks introduced by tool integration. • The fourth contribution is a proposition on how to identify safety implications due to a high level of automation of tool integration. • The fifth contribution is a proposition for a new software tool qualification process.
37

Development and Testing of Control Strategies for the Ohio State University EcoCAR Mobility Challenge Hybrid Vehicle

Rangarajan, Hariharan January 2021 (has links)
No description available.
38

Campus Sexual Assault: How Oregon University System Schools Respond

Murphy, Michael William 01 January 2011 (has links)
College is usually thought of as a time where students, often living alone for their first time, are encouraged towards healthy risk-taking behavior, as well as social, intellectual, and vocational development. Unfortunately for female students, college becomes the time of their lives where they are exposed to the highest risk of sexual victimization. Many colleges across America have taken steps to address the significant problem of sexual assault on their campuses. However, even with rising concern about the sexual victimization of college students, there remains very little systematic information published about the content of sexual assault policies, protocols and programs that exist on college campuses. Focusing on the seven schools of the Oregon University System (OUS), this study sought to examine the schools' sexual assault policies, as well as their prevention and response efforts to sexual assault. Additionally schools' willingness for assistance and training from Oregon Sexual Assault Task Force (OSATF) was also studied. Specifically, official school sexual assault policies were content analysis and secondary survey data gathered by the OSATF was examined. Results demonstrated that, in most cases, policies of the OUS schools were vague in their definitions of what constituted a sexual assault, and lacked the additional information necessary for victims to respond to their sexual victimization. However, Universities also offered various forms of educational opportunities and awareness raising activities. While this proves promising, there is clearly room for improvement. OUS schools also appeared willing to work with the OSATF to improve the delivery of their sexual assault prevention services. The findings of this thesis are important in directing future actions of the OUS when developing and implementing sexual assault response and prevention strategies.
39

Empirical Essays on Transport and Regional Economics: Safety, Intermodality, and Commuting Dynamics

Borsati, Mattia 25 June 2020 (has links)
The following doctoral thesis, sponsored by Autostrada del Brennero S.p.A. (an Italian highway concession company in charge of managing toll roads) consists on empirical essays at the crossroad between transport and regional economics. They focus on different aspects that directly involve motorways (i.e, safety, intermodality, and commuting dynamics) and they are aimed at providing further evidences that transport institutions and policy makers could take into account throughout their decision-making processes. The first chapter presents a research article that seeks to determine the impact of an average speed enforcement system in reducing highway accidents. Indeed, at the end of 2005, Autostrade per l'Italia (ASPI) and the Italian traffic police progressively deployed along the Italian tolled motorway network an average speed enforcement system, named Safety Tutor, able to determine the average speed of vehicles over a long section to encourage drivers to comply with speed limits and improve safety. To empirically test the extent to which Safety Tutor led to a reduction in both total and fatal accidents on Italian highways during the period of 2001-2017, we carried out a generalized difference-in-differences estimation using a unique panel dataset that exploits the heterogeneous accident data within all tolled motorway sectors in a quasi-experimental setting. To deal with the potential endogeneity of the non-random placement of Safety Tutor sites, we utilized an instrumental variable strategy by using the network of motorway sectors managed by ASPI and its controlled concessionaires from 2005 onwards (i.e., when the technology was available) as an instrument to predict Safety Tutor adoption. We found that a 10% increase in Safety Tutor coverage led to an average reduction in total accidents of 3.9%, whereas there is no evidence of a significant causal effect of Safety Tutor in reducing fatal accidents. The second chapter presents a research article that seeks to investigate the inter-modal competition between motorway and high-speed rail (HSR) services, as the extent to which HSR demand could be the result of a modal shift from motorways is a relevant issue in any cost-benefit analysis of HSR investments. Indeed, the development of HSR has had a notable impact on modal market shares on the routes on which its services have been implemented. To analyse whether the HSR expansion in Italy has led to a modal shift from motorway to HSR, we empirically test i) whether HSR openings adjacent to motorway sectors have reduced the total km travelled by light vehicles on these sectors during the period 2001-2017; and ii) whether this reduction has been persistent or even more evident after the opening of on-track competition between two HSR operators. To do so, we carried out a generalized difference-in-differences estimation, using a unique panel dataset that exploits the heterogeneous traffic data within all tolled motorway sectors in a quasi-experimental setting. Our findings reveal that neither HSR openings nor the opening of on-track competition led to a modal shift from motorway to HSR services, as the two transport modes are non-competing. Conversely, HSR expansion had a slightly positive impact on motorway traffic. The third chapter presents a data article in a “data in brief” format that describes a dataset on municipality-to-municipality commuting patterns in Italy over the 1991, 2001, and 2011 censuses aimed at investigating the role of transport infrastructures and the structural transformation of the economy on worker mobility. At this purpose, a core origin-destination dataset on the number of workers moving between municipalities, or within the same municipality, has been linked with further municipality covariates on jobs location, population, and the distances in meters and journey times in minutes between all municipalities. Even though these data are freely available online, they require some tedious work to organize. Therefore, this data article brings the necessary information together and makes the dataset available on request. The dataset offers applied researchers an alternative source of information to shed new lights on the changing shape of urban systems by analysing i) the impact of infrastructural endowment in providing better job accessibility, or ii) the connection between increasing commuting patterns and the structural transformation of the economy due to the tertiarization process from 1991 to 2011.
40

Early-Stage Validation of Autonomous Vehicles in Ambiguous Environments : A Systems-Theoretic Process Analysis (STPA) of an Autonomous Military Defense Industry Vehicle / Validering av autonoma fordon i oklara miljöer under tidiga utvecklingsstadier : En säkerhetsanalys med analysmetoden STPA genomförd på ett autonomt militärt fordon inom försvarsindustrin

Axelsson, Maria January 2024 (has links)
This report delves into the early developmental phase of an autonomous vehicle designed for defense applications. Navigating diverse terrains, this unmanned ground vehicle (UGV) poses unique challenges, particularly in the absence of clearly defined directives found in typical traffic scenarios. The analysis employs the Systems-Theoretic Process Analysis (STPA) to identify and anticipate risks inherent in the conceptual stage of product development. Beyond the specific UGV case, the report explores the broader landscape of validating autonomous systems. It discusses prevalent methods, emphasizing adaptability to different contexts and stages of development. By shedding light on the risks and challenges of autonomy in vehicles and examining effective validation strategies, this report aims to contribute valuable insights to the ongoing discourse surrounding autonomous vehicle development.

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