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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.
211

A systematic review of barriers and facilitators to and interventions for proxy decision-making by family carers of people with dementia

Lord, Kathryn, Livingston, G., Cooper, C. 08 1900 (has links)
No / Relatives of people with dementia report that proxy decision-making is difficult and distressing. We systematically reviewed the literature about barriers and facilitators to family carers of people with dementia making proxy decisions, and interventions used to facilitate their decision-making. We searched electronic databases and references of included papers up to February 2014. Two authors independently evaluated study quality using a checklist. We included the 30/104 papers from our search which fitted predetermined criteria and prioritized higher quality papers. Family carers report that proxy decision-making is challenging and can be distressing, especially when decisions are made against the wishes of the care recipient and support from healthcare professionals is lacking. Decision-specific manualized aids have been developed, and while results for those supporting decisions about respite and percutaneous endoscopic gastrostomy (PEG) feeding have shown promising results in pilot trials, no intervention has yet been shown to significantly reduce decisional conflict or carer burden, or increase knowledge in randomized controlled trials; a decision aid for advance care planning increased decisional conflict. We recommend development and testing of decision aids targeting the decisions carers report finding most distressing, including those around where people should live, accessing services, and end of life treatments. Being provided with information to make decisions which have not previously been considered may increase feelings of conflict, suggesting these aids should be carefully targeted.
212

Comparing proxy rated quality of life of people living with dementia in care homes

Robertson, S., Cooper, C., Hoe, J., Lord, Kathryn, Rapaport, P., Marston, L., Cousins, S., Lyketsos, C.G., Livingston, G. 21 October 2020 (has links)
Yes / . Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes. Methods. We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews. Results. Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family’s (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as ‘Poor’ (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents’ QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia. Conclusion. Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently / This research was supported by the UK Economic and Social Research Council and the National Institute of Health Research Grant number NIHR/ESRC (S.R., P.R, L.M., G.L., C.C., S.C., ES/L 001780/1); the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care North Thames at Bart’s Health NHS Trust (SR, PP, GL); the UCLH NIHR Biomedical Research Centre (GL, CC); and the Johns Hopkins Alzheimer’s Disease Research Center (C.L., P50AG005146, PI: Albert).
213

Applying Dynamic Software Updates to Computationally-Intensive Applications

Kim, Dong Kwan 22 July 2009 (has links)
Dynamic software updates change the code of a computer program while it runs, thus saving the programmer's time and using computing resources more productively. This dissertation establishes the value of and recommends practices for applying dynamic software updates to computationally-intensive applications—a computing domain characterized by long-running computations, expensive computing resources, and a tedious deployment process. This dissertation argues that updating computationally-intensive applications dynamically can reduce their time-to-discovery metrics—the total time it takes from posing a problem to arriving at a solution—and, as such, should become an intrinsic part of their software lifecycle. To support this claim, this dissertation presents the following technical contributions: (1) a distributed consistency algorithm for synchronizing dynamic software updates in a parallel HPC application, (2) an implementation of the Proxy design pattern that is more efficient than the existing implementations, and (3) a dynamic update approach for Java Virtual Machine (JVM)-based applications using the Proxy pattern to offer flexibility and efficiency advantages, making it suitable for computationally-intensive applications. The contributions of this dissertation are validated through performance benchmarks and case studies involving computationally-intensive applications from the bioinformatics and molecular dynamics simulation domains. / Ph. D.
214

Can understanding of catchment hydromorphology improve the success of Salmonidae spawning gravelrestoration? / Kan förståelse för hydromorfologin i avrinningsområden förbättra utfallet vid restaurering av lekgrus för Salmonidae?

Eckerlid, Sara January 2024 (has links)
The long history of moderating watercourses to accommodate timber floating in northern Sweden lay the ground for river restorations. One restoration method is supplementing spawning gravel for Salmonidae to lay their eggs in. The success of Salmonidae reproduction is essential for the ecology in streams as well as for the economy and culture of Sweden. However, finding appropriate locations for the gravel beds, benefiting their longevity have been difficult. The aim of this study was to investigate if hydraulic and geomorphic characteristics influence mobility of 64 restored spawning beds in 11 streams in the Vindel River catchment, Sweden. Field measurements of the spawning beds condition were taken as percentage remaining and function. Metrics of fluvial power were calculated by geospatial analysis and compared to each other by a correlation model. A linear mixed effects model was made with belonging likelihood test comparing slope, drainage area, stream power proxy, distance to lake upstream, water depth over riverbed, channel width, restoration type and all variables together to the percentage remaining. The result showed that 84% of the spawning beds had moved while 71% of the beds were recorded as functioning. No significant correlation was found between any of the investigated variables by themselves or together and percentage remaining, suggesting other variables influenced mobility of the spawning gravel. Such as variations on a local-scale and variables connected to the northern hemisphere region. The lack of adequate data, subjectivity in the condition measurements and the proxy used for stream power also influenced the result.
215

股東行動主義與惡意併購個案之研究 / Case study on the shareholder activist and hostile takeover in Taiwan

賴燕玲, Lai, Yen Ling Unknown Date (has links)
股東權益與意見在公司治理中屬重要一環,否則少數公司決策者(例如董事會或公司的CEO)會過度左右企業資源的分配,甚至發生浪費、貪污等代理問題,進而損及小股東權益,甚至勞工權益。本論文以公司治理的基本概念及架構為基礎,並以惡意併購的個案作為案例,探討並說明股東行動主義的經濟與法律意涵。其中,主要就「金融控股公司依金融控股公司法申請轉投資審核原則」法規設計,選擇具代表性個案,探討個案公司於股東治理的基礎規範與相關運作程序,包括非合意併購、委託書爭奪戰等相關法律問題。若根據目前台灣上市/櫃公司,其公司治理的實施狀況,許多法律學者均認為職業股東屬必要之罪,委託書是在目前公司所有權與經營權不分下,可能的外部監督力量。目前台灣委託書的相關規定過於保護大股東、公司派,導致小股東的權益受到一定程度的損害。若能自由化委託書收購,並且讓委託書可以在自由市場買賣,如此所創造的市場機制,據委託書的價格及外部市場機制,對於台灣過度依賴大股東或管理階層的公司治理結構會產生顯著改善效果,有效提升公司治理。本論文所選擇的個案公司,可以充分顯現上述這些方面的法律與經濟意涵。另外一個好的金融控股公司合併政策有賴一個健全之法律制度加以配套。針對金控公司是否得以所謂非合意併購達成合併之目的,金管會僅以行政命令「金融控股公司依金融控股公司法申請轉投資審核原則」與「公開收購公開發行公司有價證券管理辦法」作為主要法源,在法律上之位階上似乎有將行政命令之位階提高至法律位階之必要,本文以個案公司為例探討其相關法律問題。 關鍵字:公司治理、委託書、非合意併購、代理理論、價購委託書 / Shareholder’s interests play an important role in corporate governance. Otherwise, few decision-makers (ex. Board members, directors, etc) might misuse corporate assets and abuse in related party transactions in which interests of minority shareholders and employees will be jeopardized. This thesis will explore synergies of shareholder’s activism based on basic concepts and framework of corporate governance. In particular, case studies will focus on related regulations and practicable mechanisms of corporate governance in which certain legal issues, such as hostile takeover and proxy battle, will be elaborated based on ‘Principles of supervising investment application from financial holding companies’. Related regulations of proxy rights in Taiwan tend to protect interests of major shareholders and result in negative impacts of minority shareholders. If purchase offers of proxy could be freely traded in public, marketing mechanisms will balance the distortion of major shareholders and enhance the essence of corporate governance effectively. Case studies in this thesis therefore will reflect the above-mentioned legal and business implications. In addition, merge policies of financial conglomerate need supplementally sound regulations. In Taiwan, legal sources in financial holding companies are based on “Principles of supervising investment application from financial holding companies “ and “Regulations Governing Tender Offers for Purchase of the Securities of a Public Company “ issued by Financial Supervisory Committee of Executive Yuan. Positions of legal sources, in which case studies will be reviewed, seemingly need to be upgraded from administrative to legal level. Key word: Corporate Governance, Proxy,Hostile takeover,Agency Theory, Proxy Buying
216

Intemperismo químico e influência antropogênica em uma bacia tropical granito-gnáissica situada na Região Serrana - RJ

Costa, Amanda Cristine Santos da 20 September 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-09-20T16:23:02Z No. of bitstreams: 1 Dissertacao_AmandaCristineSantosdaCosta (1).pdf: 3976192 bytes, checksum: 2af7ce18076b8c783880d3ac0c5acba5 (MD5) / Made available in DSpace on 2017-09-20T16:23:02Z (GMT). No. of bitstreams: 1 Dissertacao_AmandaCristineSantosdaCosta (1).pdf: 3976192 bytes, checksum: 2af7ce18076b8c783880d3ac0c5acba5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / importante sistema de drenagem da Região Serrana do estado do Rio de Janeiro. É caracterizada por clima tropical de altitude úmido com pluviosidade média anual de 2300 mm e temperatura média anual de 19ºC. A geologia local é definida por granitos e gnaisses representativos da região sudeste brasileiro com domínio de quatro principais unidades litoestratigráficas: suíte Serra dos Órgãos (53%), complexo Rio Negro (14%), suíte Cordeiro (13%) e suíte Nova Friburgo (7%). A área é predominantemente florestada, porém há interferência antropogênica como atividades de agricultura, pastagem e ocupação urbana. Amostras de água foram coletadas em Fevereiro e Agosto de 2013 em 21 pontos selecionados de forma a contemplar as variações litológicas e de formas de uso do solo. Uma alíquota foi filtrada e acidificada para posterior análise de cátions e para a análise de ânions as amostras foram filtradas e congeladas. Os elementos Na+, Mg2+, Ca2+, K+, SiO2 foram analisados por ICP-OES, o elemento Al3+ por ICP-MS e PO4 3-, Cl- e SO4 2- por cromatografia iônica. Dados secundários foram levantados complementando as análises realizadas (litogeoquímica, concentração de compostos fosfatados e nitrogenados, parâmetros físico-químicos e composição da chuva). Uma análise estatística de agrupamentos separou as sub-bacias de acordo com as formas de uso do solo, mostrando forte influência sobre a qualidade das águas. Para a análise dos processos intempéricos foi selecionada uma sub-bacia de cabeceira situada em uma unidade de conservação cuja floresta encontra-se em seu clímax de maturidade, livre de influência antrópica direta. Foram reunidas informações de mineralogia essencial da subbacia, índices de saturação (PHREEQC), composição química da chuva e fluxo de elementos maiores para definir as principais reações de intemperismo atuantes e quantificar o processo de intemperismo. O plagioclásio foi identificado como principal mineral intemperizado, sendo consumido em uma taxa de 649 mol ha-1 ano-1 formando os minerais caulinita e gibbsita, e contribuindo com a liberação de no mínimo 818 e no máximo 1491 mol ha-1 ano-1 de silício no rio (valor medido). Para explicar todo este fluxo de silício medido, o solo deveria ser composto por 14% de caulinita e 86% de gibbsita em percentual relativo às duas fases minerais. Com relação à qualidade das águas superficiais foi proposta a razão Na:Si como uma alternativa simples e eficiente de avaliação da influência antrópica sob as condições de toda a bacia. Razões acima de 0,6 indicariam um ambiente afetado por atividade antrópica. Verificou-se uma boa correlação do proxy sugerido com outros compostos indicadores de poluição, com razão Na:Si mínima de 0,4 e máxima de 0,6 para pontos de cabeceira. Baixas razões de Na:Si, porém com concentrações mais elevadas de compostos nitrogenados e fosfatados foram associadas a áreas agrícolas. Para áreas onde é observada a influência de atividade antrópica urbana (esgotos domésticos), a razão apresentou valores elevados com máximo de 5,1. / The Piabanha basin is part of the Paraíba do Sul River system. It is an important drainage in the Rio de Janeiro mountainous region. It is characterized by humid altitude tropical climate with 2300mm of annual rainfall and 19ºC of average annual temperature. The local geology is defined by granites and gneisses representative of the Brazilian southeast region with the dominance of four main lithostratigraphic units: Serra dos Órgão suite (53%), Rio Negro complex (14%), Cordeiro suite (13%) and Nova Friburgo suite (7%). The area is mainly forested, however there are anthropogenic interference such as agricultural activities, pasture and urban area. Water samples were collected in February and August 2013 at 21 selected points. They were chosen to cover lithological variations and land use patterns. One aliquot was filtered and acidified for further cation analysis. Another sample aliquot was filtered and frozen to anion analysis. The elements Na+, Mg2+, Ca2+, K+, SiO2 . were analyzed by ICPOES the element Al3+ by ICP-MS and PO4 3-, Cl- and SO4 2- by ionic chromatography. Data from literature were collected (litogeochemistry, phosphate and nitrogen compounds concentration, physico-chemical parameters and rain composition). The statistical cluster analysis classified the sub-basins according to land use patterns, due to the strong influence on water quality. To the weathering processes analysis, a headwater sub-basin was selected. It is located in a conservation unit with a climax forest, free of direct anthropogenic influence. Information on this sub-basin’s essential mineralogy, saturation indexes, rain chemical composing and major elements flow were gathered so the main weathering reactions were defined in order to quantify the weathering process. The plagioclase was identified as the main weathered mineral, being consumed at a rate of 649 mol ha-1 year-1 forming the minerals kaolinite and gibbsite and contributing to the liberation of 818 at least and 1491 mols maximum ha-1 year-1 of silicon on the river (measured value). In order to explain all this measured silicon flow, the soil should be composed by 14% of kaolinite and 86% of gibbsite in percentage relative of the two mineral phases. Regarding the water quality, the Na:Si ratio was proposed as a simple and efficient way to evaluate the anthropogenic influence. Ratios above 0,6 would indicate an environment affected by anthropogenic influence. There was a good correlation of the suggested proxy with other pollutants indicator compounds, with a ratio of Na: Si minimum of 0,4 and maximum of 0,6 for headwater points. Low ratio values of Na:Si related with high concentration of N and P compounds are associated with agricultural areas because of the use of fertilizers. Areas with high urban anthropic activity showed the highest ratio values with a maximum value of 5,1.
217

Alta disponibilidade: uma abordagem com DNS e Proxy Reverso em Multi-Cloud

Pires, Luis Paulo Gon?alves 15 December 2016 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-02-01T13:15:39Z No. of bitstreams: 1 LUIS PAULO GONCALVES PIRES.pdf: 3166033 bytes, checksum: 043d546bf3a8212c07798369bfcc2f7f (MD5) / Made available in DSpace on 2017-02-01T13:15:39Z (GMT). No. of bitstreams: 1 LUIS PAULO GONCALVES PIRES.pdf: 3166033 bytes, checksum: 043d546bf3a8212c07798369bfcc2f7f (MD5) Previous issue date: 2016-12-15 / Pontif?cia Universidade Cat?lica de Campinas ? PUC Campinas / While there is considerable enthusiasm for the migration of on-premise data centers to cloud computing services, there is still some concern about the availability of these same services. This is due, for example, to historical incidents such as that in 2011, when a crash on Amazon's servers caused sites of several of its customers to go down for almost 36 hours. In view of this, it becomes necessary to develop strategies to guarantee the availability offered by the providers. In the present work, a solution is proposed, which implements high availability in Multi-Cloud environments, through the distribution of DNS access and the use of reverse proxy. A financial analysis was also carried out, taking into account market values in Cloud Computing services, which showed that the proposed solution may even be advantageous with respect to the traditional one. Specifically, a Multi-Cloud system, consisting of two Clouds with 99.90% availability each, provides total availability of 99.999%, and it costs 34% less than a single Cloud with 99.95% availability. The simulation results, obtained in a virtualized environment, using two Clouds, with availability of 99.49% and 99.43%, showed a system availability of 99.9971%. In this way, using Multi-Cloud systems it is possible to obtain high availability systems, from lower availability Clouds, according to user?s needs, besides saving with provider services costs. / A despeito de haver consider?vel entusiasmo quanto ? migra??o de data-centers on-primese para servi?os de Cloud Computing, ainda existe certo receio no que se refere ? disponibilidade destes mesmos servi?os. Isso se deve, por exemplo, a incidentes hist?ricos como o ocorrido em 2011, quando uma falha nos servidores da Amazon fez com que sites de v?rios de seus clientes ficassem fora do ar por quase 36 horas. Em vista disso, torna-se necess?rio desenvolver estrat?gias para garantir a disponibilidade oferecida pelos provedores. No presente trabalho, descreve-se uma solu??o que implementa alta disponibilidade em ambientes Multi-Cloud, mediante a distribui??o de acesso por DNS e a utiliza??o de proxy reverso. Realizou-se tamb?m uma an?lise financeira, levando-se em conta valores de mercado em servi?os de Cloud Computing, o que mostrou que a solu??o proposta pode ser mesmo vantajosa com a rela??o ? solu??o tradicional. Especificamente, um sistema Multi-Cloud, composto por duas Clouds com disponibilidade de 99,90%, que prov? disponibilidade total de 99,999%, custa 34% menos do que uma ?nica Cloud com disponibilidade de 99,95%. Os resultados de simula??o, obtidos em ambiente virtualizado, utilizando-se duas Clouds, com disponibilidades de 99,49% e 99,43%, alcan?aram disponibilidade 99,9971%. Desta forma, utilizando-se sistemas Multi-Cloud ? poss?vel se obter sistemas de alta disponibilidade, de acordo necessidade do usu?rio, a partir de Clouds de mais baixa disponibilidade, al?m de ser poss?vel economizar com os custos dos servi?os do provedor.
218

Computergestützte Entwurfsmethoden auf gekrümmten Oberflächen

Kühnert, Tom 27 August 2015 (has links) (PDF)
Im Fokus dieser Arbeit steht die Entwicklung und Realisierung einer Nutzerschnittstelle für die computergestützte Bearbeitung von Oberflächen dreidimensionaler Designobjekte, die durch herkömmliche CAD-Systeme nur unzureichend unterstützt werden können. Es werden Methoden und Algorithmen erarbeitet, um die Interaktion des Benutzers direkt auf Basis der für das Design relevanten 3D Objektoberflächen zu ermöglichen. Den Ausgangspunkt bildet das Proxy-Konzept des Forschungsfeldes zur Mensch-Maschine-Interaktion, in welchem physische Stellvertreterobjekte zur Manipulation virtueller Objekte genutzt werden. Im ersten Teil der Arbeit wird dieses Konzept um eine auf die Oberfläche des bearbeiteten Objektes bezogene Interaktion und Designfunktionalität erweitert. Dazu wird das Konzept eines CAD-Proxys entwickelt und verschiedene Umsetzungen und Anwendungen erläutert. Dabei werden die CAD-Proxys in drei Typen unterschieden. Der exakte CAD-Proxy ermöglicht es, ein virtuelles Objekt mit einem formgleichen, physischen Gegenstück zu bearbeiten. Beim abstrakten CAD-Proxy wird gezeigt, wie auch ein anders geformtes Gegenstück zum Einsatz kommen kann. Der augmentierte CAD-Proxy erlaubt die Anzeige des Designs direkt auf dem physischen Gegenstück. Nutzerstudien belegen, dass die CAD-Proxys zur Erstellung eines Designs auf einer Oberfläche deutlich besser geeignet sind als eine klassische Nutzerschnittstelle. Dies gilt insbesondere für anspruchsvolle Designaufgaben, etwa im künstlerischen Design. Im zweiten Teil der Arbeit wird die Verarbeitung von Linienzügen im Gestaltungsprozess eingeführt, welche das Konzept der aktiven Konturen auf Oberflächen erweitern. Diese Linienzüge werden auf die Form der Oberfläche bezogen verarbeitet und beachten gleichzeitig wichtige Merkmale, wie bspw. die Kanten des Objektes. Es wird ein neues Verfahren vorgestellt, mit dem aktive Konturen auch auf schlecht vernetzten Oberflächen eingesetzt werden können und gleichzeitig Formen flexibler repräsentieren können als bisherige Ansätze. Für den Bezug der Designlinien zur Oberfläche wird eine neue Datenstruktur eingeführt, die ein geometrisches Nachbarschaftsproblem löst. Es wird gezeigt, dass diese Struktur auf den getesteten Objekten mindestens um Faktor 14 schneller ist als alternative Ansätze und auch direkt auf andere Problemstellungen anwendbar ist. Der dritte Teil enthält die Betrachtungen zum Formverständnis der Designobjekte, welche für die Designlinien und die Modellierung der Designobjekte benötigt werden. Dabei kommt die Krümmungsberechnung als etabliertes Werkzeug derartiger Analysen zum Einsatz. Hier wird eine neue Betrachtung erarbeitet, die den Einfluss unterschiedlicher Faktoren auf die Genauigkeit der Krümmungsschätzung und auf die Eignung verschiedener Schätzungsverfahren erstmals umfassend untersucht. Durch die Kombination existierender Verfahren kann das Verfahren der Shape Operator Approximation entwickelt werden, welches Eigenschaften wie Schätzungsgenauigkeit, Performanz und eine einfache Formulierung bekannter Verfahren vereint.
219

Conception de protocoles cryptographiques préservant la vie privée pour les services mobiles sans contact / Design of privacy preserving cryptographic protocols for mobile contactless services

Arfaoui, Ghada 23 November 2015 (has links)
Avec l'émergence de nouvelles technologies telles que le NFC (Communication à champ proche) et l'accroissement du nombre de plates-formes mobiles, les téléphones mobiles vont devenir de plus en plus indispensables dans notre vie quotidienne. Ce contexte introduit de nouveaux défis en termes de sécurité et de respect de la vie privée. Dans cette thèse, nous nous focalisons sur les problématiques liées au respect de la vie privée dans les services NFC ainsi qu’à la protection des données privées et secrets des applications mobiles dans les environnements d'exécution de confiance (TEE). Nous fournissons deux solutions pour le transport public: une solution utilisant des cartes d'abonnement (m-pass) et une autre à base de tickets électroniques (m-ticketing). Nos solutions préservent la vie privée des utilisateurs tout en respectant les exigences fonctionnelles établies par les opérateurs de transport. À cette fin, nous proposons de nouvelles variantes de signatures de groupe ainsi que la première preuve pratique d’appartenance à un ensemble, à apport nul de connaissance, et qui ne nécessite pas de calculs de couplages du côté du prouveur. Ces améliorations permettent de réduire considérablement le temps d'exécution de ces schémas lorsqu’ils sont implémentés dans des environnements contraints par exemple sur carte à puce. Nous avons développé les protocoles de m-passe et de m-ticketing dans une carte SIM standard : la validation d'un ticket ou d'un m-pass s'effectue en moins de 300ms et ce tout en utilisant des tailles de clés adéquates. Nos solutions fonctionnent également lorsque le mobile est éteint ou lorsque sa batterie est déchargée. Si les applications s'exécutent dans un TEE, nous introduisons un nouveau protocole de migration de données privées, d'un TEE à un autre, qui assure la confidentialité et l'intégrité de ces données. Notre protocole est fondé sur l’utilisation d’un schéma de proxy de rechiffrement ainsi que sur un nouveau modèle d’architecture du TEE. Enfin, nous prouvons formellement la sécurité de nos protocoles soit dans le modèle calculatoire pour les protocoles de m-pass et de ticketing soit dans le modèle symbolique pour le protocole de migration de données entre TEE. / The increasing number of worldwide mobile platforms and the emergence of new technologies such as the NFC (Near Field Communication) lead to a growing tendency to build a user's life depending on mobile phones. This context brings also new security and privacy challenges. In this thesis, we pay further attention to privacy issues in NFC services as well as the security of the mobile applications private data and credentials namely in Trusted Execution Environments (TEE). We first provide two solutions for public transport use case: an m-pass (transport subscription card) and a m-ticketing validation protocols. Our solutions ensure users' privacy while respecting functional requirements of transport operators. To this end, we propose new variants of group signatures and the first practical set-membership proof that do not require pairing computations at the prover's side. These novelties significantly reduce the execution time of such schemes when implemented in resource constrained environments. We implemented the m-pass and m-ticketing protocols in a standard SIM card: the validation phase occurs in less than 300ms whilst using strong security parameters. Our solutions also work even when the mobile is switched off or the battery is flat. When these applications are implemented in TEE, we introduce a new TEE migration protocol that ensures the privacy and integrity of the TEE credentials and user's private data. We construct our protocol based on a proxy re-encryption scheme and a new TEE model. Finally, we formally prove the security of our protocols using either game-based experiments in the random oracle model or automated model checker of security protocols.
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Kontroll, manipulering och lögner : Socialarbetares beskrivningar av postseparationsvåld mot kvinnor / Control, manipulation and lies : Socialworkers´ descriptions of post-separation violence towards women

Engberg, Linda, Österman, Anette January 2021 (has links)
Denna kvalitativa studie syftade till att undersöka socialarbetares beskrivningar av deras erfarenheter kring postseparationsvåld mot kvinnor samt hinder och möjligheter i att motverka detta. Fem socialarbetare från olika organisationer deltog i intervjuerna. Studiens resultat visade att postseparationsvåld är vanligt förekommande men svårt att bevisa. Det framkom att de mest framträdande våldsformerna var det psykiska och ekonomiska våldet där kontroll är avgörande. Studien visade även att samhällets attityder och regelsystem kunde verka både främjande och hindrande i arbetet mot postseparationsvåld vilket vidare analyserades utifrån makt- och feministisk teori. Resultatet bekräftade den tidigare forskningen där utsatta kvinnor beskriver postseparationsvåld och hur myndigheters bedömningar och beslut kan användas som en del av mannens våld mot henne. / This qualitative study aimed to examine social workers' descriptions of their experiences concerning post-separation violence against women and the difficulties and possibilities in counteracting this. Five social workers from different organizations were interviewed. The results of the study showed that post-separation violence is common but difficult to prove. It appeared that the most prominent forms of violence were psychological and economic, where control is essential. The study also showed that attitudes and regulatory systems within society could have both a supportive and hindering effect on the work against post-separation violence. This was further analyzedusing power and feminism theories. The result confirmed previous research where women exposed to violence describe post-separation violence and how the assessments and decisions of authorities can be used as a part of the man's violence against her.

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