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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

A new maintenance strategy for Power Holding Company Nigeria to contest the current power demand problem / O.K. Ewulum

Ewulum, Ogemdi Kilian January 2008 (has links)
Power Holding Company of Nigeria (PHCN), responsible for generating, transmitting and distributing electricity in Nigeria is being faced with an apparent huge maintenance problem which seemingly contributes greatly to the power demand problem of the country. This apparent maintenance problem is investigated by surveying its root causes through interviews, questionnaires and data gathered from selected case studies. Questionnaires were used scientifically with a confidence level of 95% and interval of +-5% and +-4.4% to establish a high level of integrity on data gathered. Findings and deliverables are compared to South Africa’s power utility company Eskom for validation of the final deliverable. With the findings of this survey, the research problem was overcome by developing a new maintenance strategy and work authorization system for the company while making some recommendations on the training being given to its maintenance personnel. The New strategy called ‘Utility Availability Centered Maintenance Strategy’ or UACMS is presented in the form of a flow chart/ block diagram with its different sections fully explained. It mainly combines preventative, predictive and corrective maintenance strategies alongside other modern maintenance techniques. It’s all linked to a computer database support to ensure high effectiveness. Furthermore, the work authorization system called ‘Internal Task Authorization form’ serves to ensure responsibility in task execution within the company. During the course of this research, an excessive application of corrective maintenance strategy, lack of root cause analysis and unavailability of computer based applications were discovered in PHCN. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
32

A new maintenance strategy for Power Holding Company Nigeria to contest the current power demand problem / O.K. Ewulum

Ewulum, Ogemdi Kilian January 2008 (has links)
Power Holding Company of Nigeria (PHCN), responsible for generating, transmitting and distributing electricity in Nigeria is being faced with an apparent huge maintenance problem which seemingly contributes greatly to the power demand problem of the country. This apparent maintenance problem is investigated by surveying its root causes through interviews, questionnaires and data gathered from selected case studies. Questionnaires were used scientifically with a confidence level of 95% and interval of +-5% and +-4.4% to establish a high level of integrity on data gathered. Findings and deliverables are compared to South Africa’s power utility company Eskom for validation of the final deliverable. With the findings of this survey, the research problem was overcome by developing a new maintenance strategy and work authorization system for the company while making some recommendations on the training being given to its maintenance personnel. The New strategy called ‘Utility Availability Centered Maintenance Strategy’ or UACMS is presented in the form of a flow chart/ block diagram with its different sections fully explained. It mainly combines preventative, predictive and corrective maintenance strategies alongside other modern maintenance techniques. It’s all linked to a computer database support to ensure high effectiveness. Furthermore, the work authorization system called ‘Internal Task Authorization form’ serves to ensure responsibility in task execution within the company. During the course of this research, an excessive application of corrective maintenance strategy, lack of root cause analysis and unavailability of computer based applications were discovered in PHCN. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
33

Network Authentication to the Physical World

Sandberg, Joakim January 2018 (has links)
Quick Response (QR) codes have been used for both non-authentication purposes and authentication & authorization of a user. The visual representation of a QR code requires a reader/decoder to convert the code to a readable resource for an application. This raises some concerns, such as: What kind of information and how much information can be stored in this representation? What kind of vulnerabilities are there when using this technology in some type of authentication? The concrete problem addressed in this thesis is whether a mobile device displaying a QR code can be used as an authenticator for an Axis Communications A8105-E Network Video Door Station. To solve this problem the thesis investigates the use of QR codes in authentication & authorization based upon displaying a QR code on a mobile device, scanning this code via a camera, and then verifying the code using a validation server. Two important issues were what information to put into the QR code (given that the QR code is to be read by a camera) and where the decoding process should be carried out. This thesis also considers multiple types of authentication. Moreover, the system contains multiple components which themselves rely on secure communication and well-designed protocols to ensure security (against popular methods of attack) and stability. A prototype of the proposed authentication process was evaluated using a testbed consisting of three door stations, an Android app, and a backend service for analysing QR codes and making an authentication & authorization decision. QR codes proved to be as secure as the current solutions, such as magnetic stripe or RFID access cards. Using QR codes together with the user’s mobile device also offered additional functionality, such as easy management of the device registration/deregistration and compatibility with multifactor authentication. The conclusion is with the current door station products and the finalized design of the software; it is possible to have a secure and scalable system which is also cost-effective by eliminating the need of human verification as well as equipment required for access card systems. / Quick-Response (QR) koder har använts både för icke autentiseringssyften men även för just autentisering av en användare. Den visuella representationen av en QR-kod behöver en läsare för att kunna omvandla koden till en läsbar resurs för en applikation. Detta leder till frågeställningarna: Vad för information och hur mycket kan man lagra i en QR-kod? Vilka sårbarheter finns det med användningen av denna teknologi inom autentisering? Det konkreta problemet i detta examensarbete är huruvida en mobil enhet som visar en QR-kod kan användas med en Axis Communications A8105-E Network Video Door Station. För att lösa detta problem så undersöker detta arbete användningen av QR-koder inom autentisering baserat på att visa QR koden på den mobila enheten, skanna denna kod med en kamera och validera denna kod med en valideringsserver. Två viktiga frågor var vilken information som skulle lagras i QR-koden samt vart avläsningen av en QR-kod tog plats. Detta arbete undersöker också olika typer av multifaktor autentisering. Systemet består vidare av flera komponenter som förlitar sig på säker kommunikation och väldesignade protokoll sam ger säkerhet (mot de mest populära nätverksattackerna) och stabilitet. Den tänkta autentiseringsprocessens prototyp evaluerades i en testmiljö bestående av tre Door Station, en Android applikation och en backend service för att analysera QR-koder samt hantera autentiserings och behörighetslogik. QR-koder bevisades vara lika säkert som befintliga lösningar som till exempel kort accesskort med magnetremsa och RFID chip. Användning av QR-koder med de mobila enheterna gör dessutom att hantering av registrering/avregistrering av enheterna kan ske på ett enkelt sätt samt även integreras med multifaktor autentisering. Slutsatsen är att med de befintliga Door Station enheterna och den slutgiltiga designen av mjukvaran ger det säkert och skalbart system som dessutom är kostnadseffektivt genom att behovet av en mänsklig verifiering samt de fysiska komponenterna av befintliga accesskortsystem, inte längre finns.
34

Securing Print Services for Telemetry Post-Processing Applications

Hines, Larry, Kalibjian, Jeff 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / One of the primary goals of telemetry post processing is to format received data for review and analysis. This occurs by both displaying processed data on video monitors and by printing out the results to hardcopy media. Controlling access (i.e. viewing) of telemetry data in soft form (i.e. video monitor) is achieved by utilizing the existing framework of authentication and authorization on the client/server machines hosting the telemetry data (and post processing applications). Controlling access to hardcopy output has historically been much more problematic. This paper discusses how to implement secure printing services for telemetry post processing applications.
35

What Are the Security Challenges Concerning Maintenance Data in the Railway Industry

Khan, Hiba January 2019 (has links)
Recently, technology advancement has brought improvement in all the sectors, including the railway sector. The Internet of Things (IoT) based railway systems have immense potential to improve quality and systems that will enable more efficient, environmental friendly railway system. Many research brought innovations that offer enormous benefits for rail travel. The current research focuses on the railway industries, as they want to reap the benefits of IT concept such as Cloud Computing, Information Security, and Internet of Things (IoT). Railway industries are generating a large volume of data every day from different sources. In addition, machine and human interactions are rapidly increasing along with the development of technologies. This data need to be properly gathered, analysed and shared in a way that it is safe from different types of cyberattacks and calamities. To overcome smart devices’ and Cloud’s limitations, the new paradigm known as Fog computing has appeared. In which an additional layer processes the data and sends the results to the Cloud. Despite numerous benefits of Fog, computing brings into IoT-based environments, privacy and security issues remain the main challenge for its implementation. Hence, the primary purpose of this research is to investigate the potential challenges, consequences, threats, vulnerabilities, and risk management of data security in the railway infrastructure in the context of eMaintenance.
36

Právní režim pozemků pro výstavbu / The legal regime of the building land

Ouvínová, Kristýna January 2018 (has links)
This diploma thesis describes the legal regime of the building land, which is regulated by the legislation of the private and public law, and focuses on the recent amendment of the building code as amended by the act no. 225/2017 Sb. The use of the legal regulations is displayed in the case study analysing the legal regime of the specific lands designated for the construction. The main aim of this thesis is to characterize the process and the institutes of the public and the private law as having the crucial influence on the building land, to focus on their mutual connection and to demonstrate their application in the case study. According to the last amendment of the building code the aim of this thesis is to refer to the new or modified institutes influencing the legal regime of the building lands and to define the relevance of the amendment for the construction. The diploma thesis consists of four chapters. The first chapter includes the introductory information. The general listing and the description of the legal sources, the fundamental legal terms connected with the building lands and the characterization of the case study of the shopping centre is described in this chapter. The second chapter deals with the civil law regime of the building lands and analysis the civil law institutes such as the...
37

Proposta de arquitetura e solução de gerenciamento de credenciais para autenticação e autorização em ambientes de computação em nuvem. / Proposal of architecture and solution for credential, management for authentication and authorization in cloud computing environments.

Gonzalez, Nelson Mimura 22 January 2014 (has links)
O modelo de computação em nuvem (cloud computing) reúne características como elasticidade, compartilhamento de recursos, obtenção de serviços sob demanda, e escalabilidade. Este modelo aumenta a eficiência de utilização de recursos, reduzindo drasticamente o custo de manutenção de infraestruturas de hardware e software. Contudo, diversos problemas relacionados a aspectos de segurança são observados nos ambientes de nuvem, o que reduz a adoção da tecnologia de maneira significativa. Os principais problemas identificados referem-se à confidencialidade dos dados dos usuário e à proteção dos canais de comunicação. Estes problemas podem ser resolvidos por meio do emprego de mecanismos de autenticação e autorização que controlem efetivamente o acesso aos recursos e aos serviços da nuvem por parte dos usuários e quaisquer outras entidades que consigam acessar estes elementos. Isto sugere a utilização de credenciais, que permitem estabelecer permissões e obrigações das entidades de um ecossistema de computação em nuvem. Esta dissertação apresenta uma proposta de Sistema de Gerenciamento de Credenciais (SGC) para computação em nuvem, que visa implementar uma solução de identificação de entidades e controle de acesso à nuvem. Para isto foi realizada uma pesquisa para levantar as principais referências relativas à computação em nuvem, segurança em computação em nuvem, e gerenciamento de credenciais. A partir dos resultados desta pesquisa, foi definido um modelo conceitual que descreve a solução proposta, identificando os seus requisitos e a sua arquitetura. Finalmente foi desenvolvido um protótipo para realização de testes, de modo a validar a solução proposta e verificar o atendimento aos requisitos definidos previamente. Os resultados revelam a possibilidade de desenvolver um Sistema de Gerenciamento de Credenciais (SGC) capaz de prover os mecanismos de segurança adequados para a nuvem sem a necessidade de modificar as aplicações e serviços originais da mesma, culminando em uma solução transparente para usuários, desenvolvedores, e administradores da nuvem. O sistema proposto foi, também, capaz de estabelecer canais de comunicação seguro entre as entidades da nuvem, permitindo proteger de maneira seletiva as informações que trafegam pela rede. Desta forma, é possível afirmar que soluções em nuvem podem ser tornar mais seguras (e confiáveis) por meio do emprego de mecanismos transparentes e abrangentes para autenticação e autorização de entidades e operações. / Cloud computing is a computing model based on characteristics such as elasticity, resource sharing, on-demand resource acquisition, and scalability. This model increases resource usage efficiency, drastically reducing maintenance costs of hardware and software infrastructures. However, problems related to security aspects represent obstacles for a wider adoption of the technology. The main problems identified are related to data confidentiality and communication channels protection. These problems can be addressed by authentication and authorization mechanisms which are able to effectively control the access to resources and services. This suggests the use of credentials which define the permissions and obligations of entities from a cloud computing ecosystem. This work presents a Credential Management System (CMS) for cloud computing, which implements a solution for identification and access control in the cloud environment. The research included a survey of references related to cloud computing, security in cloud computing, and credential management. Taking the results of this research, it was specified a conceptual model which describes the proposed solution, identifying the main requirements of the solution and its architecture. Finally it was developed a prototype in order to perform tests to validate the solution and verify if the requirements were addressed. The results reveal the possibility of developing a credential management solution able to provide the adequate security mechanisms without the need to modify the original applications and services, leading to a transparent solution for users, developers, and cloud administrators. The solution was also able to establish secure communication channels between cloud entities, allowing to selectively protect information that is exchanged in the network. The conclusion is that it is possible to make cloud applications and services more secure (and reliable) by using transparent and comprehensive mechanisms for authentication and authorization of entities and operations.
38

Vem granskar vem? / Who reviews whom?

Bülling, Emelie, Lind, Annchristine January 2011 (has links)
Senast som revisionsplikten var föremål för aktiebolagskommitténs arbete var 1995. Skälet som angavs då för inskränkning av revisionsplikten var att revisionen innebar en kostnad för företagen. Vid det tillfället skedde inga ändringar då revisionsplikten ansågs förhindra ekonomisk brottslighet i framförallt de mindre bolagen med ett litet aktiekapital. Vid ett möte i mars 2007 betonade det Europeiska rådet kraftiga gemensamma insatser för att minska de administrativa bördorna för företag. Det betonades att små och medelstora företags kostnader för revision och redovisning är särskilt betungande. Den 1 november 2010 avskaffades revisionsplikten i Sverige för aktiebolag som underskrider två av tre följande värden: 3 mnkr i nettoomsättning, 1,5 mnkr i balansomslutning och tre anställda.Uppsatsen fokuserar på hur aktören redovisningskonsult har påverkats av den frivilliga revisionen och följande fråga kan ställas: Innebär den frivilliga revisionen att auktoriserade redovisningskonsulter kan komma att få en alltmer framträdande och betydande roll bland de mindre bolagen och intressenterna och i sådana fall hur?Syftet med denna studie är att övergripande undersöka och belysa redovisningskonsultens mer framträdande roll och ansvar efter det att reglerna om frivillig revision trätt i kraft. I studien har vi även försökt klarlägga om redovisningskonsulten har fått något indirekt ökat ansvar efter det att reformen trätt i kraft och hur det kan ha påverkat intressenterna. Avsikten med litteraturgenomgången är att belysa samt är att ge en översiktsbild av redovisningskonsulten.Empirin består av kvalitativa intervjuer som har genomförts med intressenter som har påverkats av den frivilliga revisionen. Det empiriska materialet har sammanställts för att sedan analyseras genom vår fördjupade litteraturgenomgång. Från resultatet som framkommer ur vår analys kan slutsatsen dras att den frivilliga revisonen leder till att den auktoriserade redovisningskonsulten kommer få en mer betydande roll. Den nya situationen kommer att leda till omstruktureringar i branschen och redovisningskonsultens roll och ansvar blir mer framträdande. Studiens avsikt och resultat bidrar till att lyfta fram och skapa en helhetsbild av redovisningskonsulten som kan sättas in i en större kontext inom redovisningen. / Program: Civilekonomprogrammet
39

Um serviço de autorização Java EE baseado em certificados de atributos X.509. / A Java EE authorization service based on X.509 attribute certificates.

Guilhen, Stefan Neusatz 03 June 2008 (has links)
O surgimento e a popularização de arquiteturas de software que fornecem suporte à programação distribuída orientada a objetos, como CORBA, .NET e Java EE, gerou uma demanda por infra-estruturas de segurança eficientes, capazes de proteger os recursos dos sistemas de ataques maliciosos. Essa proteção começa pela identificação dos usuários que interagem com os sistemas, processo conhecido como autenticação. Entretanto, a autenticação por si só não é suficiente para garantir a segurança dos recursos, uma vez que a autenticação não determina quais ações os usuários estão autorizados a executar depois de autenticados. Em outras palavras, um mecanismo de autorização, que faz valer as políticas de controle de acesso aos recursos definidas pelos administradores de sistemas, se faz necessário. Neste trabalho estudamos mecanismos de controle de acesso baseado em papéis e a aplicabilidade dos certificados de atributos X.509 como estrutura de armazenamento desses papéis em um ambiente Java EE. Em particular, estendemos a infra-estrutura de segurança do servidor de aplicações JBoss, de modo que ela passasse a comportar os certificados de atributos X.509. Além disso, analisamos as vantagens e desvantagens do uso de tais certificados e avaliamos o desempenho da extensão desenvolvida em relação a outras alternativas que são oferecidas pelo JBoss para o armazenamento de papéis dos usuários. / The popularization of software architectures that provide support for distributed object-oriented programming, like CORBA, .NET, and Java EE, revealed the need for efficient security infrastructures to protect the resources of enterprise systems from malicious attacks. This protection usually begins with the identification of the users that interact with the systems, a process known as authentication. However, authentication alone is not enough to guarantee the protection of the resources, as it cannot determine what actions a particular user is allowed to execute on a given resource. In other words, an authorization mechanism is needed in order to enforce the access control policies as defined by the system administrators. In this dissertation we studied role-based access control mechanisms and the use of X.509 attribute certificates as data structures that store the users roles in a Java EE environment. Particularly, we added X.509 attribute certificates support to the existing JBoss application server security infrastructure. Furthermore, we evaluated the pros and cons of using these certificates, and compared the performance of the developed extension to the performance of the existing solutions provided by JBoss to store the users roles.
40

Proposta de arquitetura e solução de gerenciamento de credenciais para autenticação e autorização em ambientes de computação em nuvem. / Proposal of architecture and solution for credential, management for authentication and authorization in cloud computing environments.

Nelson Mimura Gonzalez 22 January 2014 (has links)
O modelo de computação em nuvem (cloud computing) reúne características como elasticidade, compartilhamento de recursos, obtenção de serviços sob demanda, e escalabilidade. Este modelo aumenta a eficiência de utilização de recursos, reduzindo drasticamente o custo de manutenção de infraestruturas de hardware e software. Contudo, diversos problemas relacionados a aspectos de segurança são observados nos ambientes de nuvem, o que reduz a adoção da tecnologia de maneira significativa. Os principais problemas identificados referem-se à confidencialidade dos dados dos usuário e à proteção dos canais de comunicação. Estes problemas podem ser resolvidos por meio do emprego de mecanismos de autenticação e autorização que controlem efetivamente o acesso aos recursos e aos serviços da nuvem por parte dos usuários e quaisquer outras entidades que consigam acessar estes elementos. Isto sugere a utilização de credenciais, que permitem estabelecer permissões e obrigações das entidades de um ecossistema de computação em nuvem. Esta dissertação apresenta uma proposta de Sistema de Gerenciamento de Credenciais (SGC) para computação em nuvem, que visa implementar uma solução de identificação de entidades e controle de acesso à nuvem. Para isto foi realizada uma pesquisa para levantar as principais referências relativas à computação em nuvem, segurança em computação em nuvem, e gerenciamento de credenciais. A partir dos resultados desta pesquisa, foi definido um modelo conceitual que descreve a solução proposta, identificando os seus requisitos e a sua arquitetura. Finalmente foi desenvolvido um protótipo para realização de testes, de modo a validar a solução proposta e verificar o atendimento aos requisitos definidos previamente. Os resultados revelam a possibilidade de desenvolver um Sistema de Gerenciamento de Credenciais (SGC) capaz de prover os mecanismos de segurança adequados para a nuvem sem a necessidade de modificar as aplicações e serviços originais da mesma, culminando em uma solução transparente para usuários, desenvolvedores, e administradores da nuvem. O sistema proposto foi, também, capaz de estabelecer canais de comunicação seguro entre as entidades da nuvem, permitindo proteger de maneira seletiva as informações que trafegam pela rede. Desta forma, é possível afirmar que soluções em nuvem podem ser tornar mais seguras (e confiáveis) por meio do emprego de mecanismos transparentes e abrangentes para autenticação e autorização de entidades e operações. / Cloud computing is a computing model based on characteristics such as elasticity, resource sharing, on-demand resource acquisition, and scalability. This model increases resource usage efficiency, drastically reducing maintenance costs of hardware and software infrastructures. However, problems related to security aspects represent obstacles for a wider adoption of the technology. The main problems identified are related to data confidentiality and communication channels protection. These problems can be addressed by authentication and authorization mechanisms which are able to effectively control the access to resources and services. This suggests the use of credentials which define the permissions and obligations of entities from a cloud computing ecosystem. This work presents a Credential Management System (CMS) for cloud computing, which implements a solution for identification and access control in the cloud environment. The research included a survey of references related to cloud computing, security in cloud computing, and credential management. Taking the results of this research, it was specified a conceptual model which describes the proposed solution, identifying the main requirements of the solution and its architecture. Finally it was developed a prototype in order to perform tests to validate the solution and verify if the requirements were addressed. The results reveal the possibility of developing a credential management solution able to provide the adequate security mechanisms without the need to modify the original applications and services, leading to a transparent solution for users, developers, and cloud administrators. The solution was also able to establish secure communication channels between cloud entities, allowing to selectively protect information that is exchanged in the network. The conclusion is that it is possible to make cloud applications and services more secure (and reliable) by using transparent and comprehensive mechanisms for authentication and authorization of entities and operations.

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