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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.
251

Relevância da taxa de desconto atuarial na avaliação dos benefícios pós-emprego com características de benefício definido de previdência privada fechada e seus reflexos na patrocinadora

Sartori, Robinson Luis January 2015 (has links)
A previdência complementar é um importante instrumento para a complementação de renda na aposentadoria e configura-se como benefício atrativo às carreiras que as provêm. Pela própria natureza, geralmente produz efeitos a longo prazo e demanda avaliação atuarial para a determinação da saúde financeira dos planos, utilizando-se, para tal, de premissas aderentes às características econômicas e biográficas da população alvo. A presente dissertação procura, a partir da premissa taxa de desconto, apresentar as variações da obrigação atuarial frente ao nível da taxa de juros, principalmente quando aplicada a um cenário de oscilação relevante desta última. Procura-se identificar a pertinência da variação de uma obrigação de longo prazo em virtude de uma premissa que varia no curto prazo. O estudo foca os reflexos nas patrocinadoras de benefícios pós-emprego com características de benefício definido de previdência privada fechada, conforme normativos emitidos pelo IASB (International Accounting Standards Board), CPC (Comitê de Pronunciamentos Contábeis) e CVM (Comissão de Valores Mobiliários). / The complementary pension is an important tool for supplementary income in retirement and appears as attractive benefit to careers that offer. Generally produces long-term effects and demand actuarial valuation to determine the financial health of the plans, using up to this end, economic assumptions and biographical characteristics of the target population. This dissertation seeks from the discount rate assumption, demonstrate the variations of actuarial liabilities against the level of interest rates, especially when applied to a relevant oscillation scenario. Seek to identify the relevance of changes in a long-term obligation by virtue of a premise that varies in the short term. The study focuses on the reflex in the sponsors of postemployment benefits with defined benefit characteristics of closed pension, conform regulations issued by the IASB (International Accounting Standards Board), CPC (Accounting Pronouncements Committee) and CVM (Brazilian Securities Commission).
252

ARKHAM : an advanced refinement toolkit for handling service level agreements in software-defined networking / ARKHAM : um avançado conjunto de ferramentas de refinamento para manipulação de acordos de nível de serviço em redes definidas por software

Machado, Cristian Cleder January 2015 (has links)
Redes definidas por software (Software-Defined Networking – SDN) tem como objetivo fornecer uma arquitetura mais sofisticada e precisa para gerenciar e monitorar o tráfego da rede. SDN permite centralizar parte da lógica de tomada de decisão sobre o processamento de fluxo e roteamento de pacotes em dispositivos chamados controladores. Apesar disso, o comportamento dos dispositivos de rede e suas configurações são muitas vezes escritos para situações específicas diretamente no controlador. Isto torna-se um problema quando há um aumento no número de elementos, ligações e serviços de rede, resultando numa grande quantidade de regras e uma elevada sobrecarga relacionada à configuração da rede. Como alternativa , técnicas, tais como gerenciamento baseado em políticas (Policy-Based Management – PBM) e refinamento de políticas podem ser utilizadas por operadores de alto nível para escrever Acordos de Nível de Serviço (Service Level Agreements – SLAs) em uma interface amigável, sem a necessidade de alterar o código implementado nos controladores. No entanto, o refinamento de políticas na nova área de pesquisa SDN tem sido um tema negligenciado, em parte, porque o refinamento não é um processo trivial. Ao utilizar SLAs, a sua tradução para políticas de baixo nível, por exemplo, regras para a configuração de elementos de comutação, não é simples. Se essa tradução não for realizada corretamente, os elementos do sistema podem não ser capaz de cumprir os requisitos implícitos especificados no SLA. Neste contexto, este trabalho apresenta ARKHAM: um avançado conjunto de ferramentas de refinamento para manipulação de acordos de nível de serviço em redes definidas por software. Este conjunto de ferramentas é composto por (i) um framework para criação de políticas que usa raciocínio lógico para a especificação de objetivos de nível de negócio e automatização de seu refinamento; (ii) um controlador OpenFlow que realiza a coleta de informações e implantação de configurações na rede; e (iii) uma representação formal de políticas de alto nível utilizando Event Calculus e aplicando raciocínio lógico para modelar tanto o comportamento do sistema quanto o processo de refinamento de políticas para o gerenciamento de SDN. Como resultado, a abordagem é capaz de identificar as necessidades e os recursos que precisam ser configurados de acordo com o refinamento do SLA, podendo assim configurar e executar com sucesso ações dinâmicas de suporte à reconfiguração de infraestrutura. / Software-Defined Networking (SDN) aims to provide a more sophisticated and accurate architecture for managing and monitoring network traffic. SDN permits centralizing part of the decision-making logic regarding flow processing and packet routing in controller devices. Despite this, the behavior of network devices and their configurations are often written for specific situations directly in the controller. This becomes an issue when there is an increase in the number of network elements, links, and services, resulting in a large amount of rules and a high overhead related to network configuration. As an alternative, techniques such as Policy- Based Management (PBM) and policy refinement can be used by high-level operators to write Service Level Agreements (SLAs) in a user-friendly interface without the need to change the code implemented in the controllers. However, policy refinement in the new research area of SDN has been a neglected topic, in part, because refinement is a nontrivial process. When using SLAs, their translation to low-level policies, e.g., rules for configuring switching elements, is not straightforward. If this translation is not performed properly, the system elements may not be able to meet the implicit requirements specified in the SLA. In this context, we introduce ARKHAM: an Advanced Refinement Toolkit for Handling Service Level Agreements in Software-Defined Networking. This work presents (i) a Policy Authoring Framework that uses logical reasoning for the specification of business-level goals and to automate their refinement; (ii) an OpenFlow controller which performs information gathering and configuration deployment; and (iii) a formal representation using event calculus that describes our solution. As a result, our approach is capable of identifying the requirements and resources that need to be configured in accordance with SLA refinement, and can successfully configure and execute dynamic actions for supporting infrastructure reconfiguration.
253

Resiliência em redes definidas por software através de replicação

Fonseca, Paulo César da Rocha 30 July 2013 (has links)
Made available in DSpace on 2015-04-11T14:02:49Z (GMT). No. of bitstreams: 1 paulo cesar.pdf: 2356898 bytes, checksum: 3103951fb7cb8f61e3fd1e03b8817b22 (MD5) Previous issue date: 2013-07-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Software-Defined Network (SDN) is a new paradigm that allows the development of innovative network management applications and provides a new way to look for the resolution of problems which exist throughout the Internet today. In order to simplify the task of managing the network most of SDN architectures uses a centralized network management approach. However, such approach raises, among other problems, the issue of a single point of failure, that can compromise the proper functioning of the network. A proven method to achieve a higher level of network resilience is to use a replication technique. The aim of this work is to investigate: (1) how different replication techniques relate to each other, (2) how each one performs on the task of providing resilience to a SDN, and (3) which technique is the most suitable for different scenarios. Replication techniques are mainly classified in two types: passive and active replication.This work is one of the first to address this issue. For the purpose of proof-of-concept, the replication mechanisms implemented work for networks with one switch enabled for SDN protocol. Our results show that replication is a suitable way to increase resilience in a SDN and to build these services for networks using SDN is straightforward and much less complex. / Redes definidas por software (Software Defined Networking ou SDN) é um novo paradigma para o desenvolvimento de aplicações inovadoras de gestão de redes e uma nova forma de olhar para a resolução de muitos problemas que existem em toda a Internet hoje. A arquitetura mais popular para a implantação deste paradigma é o gerenciamento de rede centralizado, uma vez que o seu uso permite simplificar a tarefa complexa e difícil de controlar os serviços de uma rede. Um dos problemas levantados pela abordagem de controle centralizado e amplamente discutido na literatura é a questão de falha em um único ponto da rede, que pode comprometer negativamente o funcionamento de toda ela. Um método comprovado para alcançar um maior nível de tolerância a falhas é a utilização da técnica de replicação. O objetivo deste trabalho é dividido em três partes: (1) comparar diferentes técnicas de replicação, (2) verificar como cada uma desempenha a tarefa de proporcionar resiliência a uma SDN, e (3) investigar qual técnica é a mais adequada para diferentes cenários. Técnicas de replicação são principalmente classificadas em dois tipos: de replicação passiva e ativa. Este trabalho é um dos primeiros a tratar este problema. Para fins de prova-de-conceito, os mecanismos de replicação implementados funcionam para redes com um switch habilitado para o protocolo SDN. Nossos resultados mostram que a replicação é uma forma adequada para aumentar a resiliência em uma SDN e construir estes serviços para redes utilizando SDN é muito menos complexo e simples.
254

Modulador do sistema ATSC 3.0 usando Gnuradio Companion

Dionísio, Victor Morales 07 August 2017 (has links)
Submitted by Marta Toyoda (1144061@mackenzie.br) on 2018-02-07T23:34:13Z No. of bitstreams: 2 VICTOR MORALES DIONISIO.pdf: 15019971 bytes, checksum: cc45d6dd4e5209047a4c19cbfbe5eb00 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2018-02-22T13:35:18Z (GMT) No. of bitstreams: 2 VICTOR MORALES DIONISIO.pdf: 15019971 bytes, checksum: cc45d6dd4e5209047a4c19cbfbe5eb00 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-22T13:35:18Z (GMT). No. of bitstreams: 2 VICTOR MORALES DIONISIO.pdf: 15019971 bytes, checksum: cc45d6dd4e5209047a4c19cbfbe5eb00 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-07 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fundo Mackenzie de Pesquisa / This paper presents the characteristics of two recent technologies on the scienti c and telecommunications community: the Advanced Television Systems Committee (ATSC) 3.0; the Software De ned Radio (SDR). Later, the usage of the three is studied by developing the modulator of the ATSC 3.0 system with SDR technique and the GNURadio Companion (GRC). In order to prove the integrity of the modulator implementation, the transmitted signal is tested with the Dektec receiver, composed by the DTA-2131 hardware and the Atsc3Xpress software. All the codes are developed in C++ language and the tests made in GRC. Such tests prove the integrity of the implementation since the receiver was able to demodulate the signal correctly, and that the SDR platform is a suitable tool for prototyping and researching digital TV transmission systems. / Este projeto apresenta as definições e características de duas tecnologias recentes na comunidade científica e de telecomunicações: o Advanced Television Systems Committee (ATSC) 3.0; o Rádio Definido por Software, do inglês Software Defined Radio (SDR). Posteriormente, investiga a combinação delas, desenvolvendo um modulador do sistema ATSC 3.0 por meio da técnica de SDR, utilizando o software GNURadio Companion (GRC). Com o intuito de comprovar a integridade da implementação do modulador, o sinal _e testado com o receptor, composto pelo hardware DTA-2131 e software Atsc3Xpress da Dektec. O desenvolvimento do sistema _e feito por meio de algoritmos computacionais em linguagem C++ e os testes são feitos no GRC. Tais testes comprovam a integridade da implementação uma vez que o receptor foi capaz de demodular o sinal corretamente, e que a plataforma de SDR _e uma ferramenta adequada para prototipagem e pesquisa de sistemas de transmissão de TV digital.
255

Software Defined Network : Med openflow

Andersson, Peter, Blomqvist, Robin January 2016 (has links)
Detta projekt har haft som mål att skapa ett redundant SDN-nätverk som ska ligga som grund för ett fiktivt företag. Företeaget ska kunna använda nätverket som vi bygger upp för att vidareutveckla detta och anpassa det efter verksamhetens behov. Nätverket byggs upp med mininet som används för att simulera en nätverksmiljö. Det fiktiva företaget ska sedan bara kunna lyfta ut nätverket från mininet ut till ett riktigt nätverk. Nätverkets funktioner, såsom protokollen STP och LACP implementeras med hjälp av programmeringsspråket python. / The goal for this project is to setup a redundant Software Defined Network for a fictive company. The company should be able to use the network for future network extension. The network will be built in mininet. Mininet is a software that is used to simulate a real network environment. The company should also be able to take the simulated network in mininet and implement it in to a real network. The protocols STP and LACP are implemented in the network by means of the programming language python.
256

Design and Implementation of a Tool for Automating Cluster Configuration : For a Software Defined Storage System

Marakani, Sindhusha January 2015 (has links)
Context Traditional storage systems are proving to be inefficient to handle the growing storage need of a modern IT organization. The need for a cost effective and scalable storage framework has led to the development of a Software Defined Storage (SDS) solution. SDS can be defined as an enterprise class distributed storage solution that uses standard hardware, with all the important storage and management functions performed by an intelligent software. Configuring and maintenance of these storage clusters require converting an SDS from any unknown state to a predefined, known state. This configuration of the SDS is best done with minimal human intervention, to ensure minimal errors and save the man hours spent in the configuration process. Objectives A tool for automatic configuration of a SDS storage cluster has been designed and implemented. The tool has later been used to study the man hours saved in the configuration of the SDS cluster. The study also involves a cost-benefit analysis to estimate the break-even point for such a tool to motivate the automation of a SDS cluster configuration process. Methodology In this study, experts from the field of Software Defined Storage have been interviewed to identify interesting and most common states of a SDS cluster. Later a tool was build such that it communicates with the underlying SDS storage cluster to configure it into one of the identified final states. This tool built was later used to conduct experiments wherein the amount of man hours saved by automating the process of cluster configuration was calculated.    Results The tool built was validated through results obtained from the experiments which show that the work time involved in the process of cluster configuration is reduced by 90% - 96% (based on the complexity of the cluster configuration). Also, the lead times of the configuration process are similar when configuring simple states but is greatly reduced by automation when performing complex configurations. Conclusions Similar to any other software automation, the process of automating the configuration of a distributed storage cluster has proven to be beneficial. Automating the process of cluster configuration saves time, reduces human errors induced in the configuration process and improves repeatability of the configuration process. Through the cost-benefit analysis of the complete process, the use of the tool beyond 20 days is deemed profitable for the organization.
257

Member choice in a defined contribution pension plan : decision-making factors

Van Schalkwyk, Cornelis Hendrik 01 May 2013 (has links)
Ph.D. (Finance) / The majority of private pension plans offered by employers are defined contribution plans where the risk is borne by the member. In a member-directed pension plan, the individual members need to make decisions regarding the investment of their contributions. The board of trustees usually provide them with a number of options to choose from. This research answers the question: which factors influence the investment decisions of members of member-directed defined contribution pension plans? The study makes a unique contribution to the field of retirement finance by determining the impact of financial risk tolerance, demographics, behavioural factors, and pension plan design and presentation factors on the investment decisions of members of a member-directed defined contribution pension plan. The results of the study inform a number of role players in the pension value chain to ultimately aid the pension plan member to effect a more optimal investment choice. A survey approach was followed to collect primary data to analyse together with secondary data within a quantitative research paradigm. A census was conducted on individuals who were members of the member-directed defined contribution pension plan of a South African higher education institution on 31 March 2008. A structured questionnaire was used to collect data on members’ demographics, financial risk tolerance, behavioural factors, and pension plan design and presentation factors. Secondary data consisted of additional demographic factors, which were available on the employers’ information system and data on member investment decisions obtained from the administrators of the pension plan. Of the 879 survey instruments distributed, 620 were returned at least partially completed and could be used in the study.
258

Perceptions of dental fluorosis in the Central Karoo District of the Western Cape Province

Rickers, B. G. January 2013 (has links)
Masters of Public Health - see Magister Public Health / Dental fluorosis is an endemic condition in a number of regions of South Africa, varying in degree of affliction according to the drinking water fluoride concentration in the area. Objective: While a number of South African studies have reported on the relationship between fluorosis and fluoride concentration in the drinking water, the purpose of this study was to determine perceptions of dental fluorosis in the Central Karoo District of the Western Cape. Methods: Learners aged 12-15 years and who had been lifelong residents in their respective areas were selected from schools in Leeu Gamka, Merweville, Nelspoort and Murraysburg. All the children meeting the inclusion criteria were included realising a total sample of 189. Drinking water fluoride concentration of each town was determined and concomitant fluorosis affliction was assessed. An interviewer administered questionnaire was used to determine respondents’ self-rated perceptions of fluorosis as well as their responses to a set of statements on clinically defined fluorosis. To this end four photographs, each depicting a different degree of fluorosis: (No fluorosis; Mild fluorosis; Moderate fluorosis; Severe fluorosis) were shown to the respondents. Results: In Leeu Gamka, with the highest fluoride concentration ([F] = 1.62ppm), 82% of respondents were aware of fluorosis stains as opposed to 6%-20% awareness in Merweville ([F] = 0.68), Nelspoort ([F] = 0.70) and Murraysburg ([F] = 0.56). Two thirds of respondents in Leeu Gamka found the appearance of their teeth embarrassing compared to only 2%-10% in the other 3 areas. The majority of respondents in Leeu Gamka (82%) indicated that they would want to remove the fluorosis spots with only 4%-20% in the lower fluoride areas. Two thirds (67%) of the Leeu Gamka respondents were teased compared to 2%-6% in the other areas. Most of the respondents have not tried to do anything to the appearance of the teeth, even in the higher fluoride area of Leeu Gamka. The average response varied little for all the photographs across the geographic areas (the minimum and maximum scores varied between 4.00 and 5.00) and reflected a greater tendency towards strongly disagreeing with the statement on aesthetics-even for the photographs depicting no fluorosis and mild fluorosis. The average response varied between 1 and 2 among all four geographic regions showing a tendency to “agree” and “strongly agree” to the statement on embarrassment. The average response to the statement on neglect varied little for all the photographs across the geographic areas as the minimum and maximum average response scores varied between 1.36 and 2.39 (agree and strongly agree). The response to the statement on disadvantage varied little for all the four photographs across the geographic areas (minimum=1.00, maximum=2.07) and reflected a greater tendency toward strongly agreeing and agreeing with the statement. Conclusion: The respondents from the higher fluoride area were more aware of dental fluorosis, had a greater perception of embarrassment and the strongest desire to remove the fluorosis staining. There was little variation in the average response to the statements on clinically defined fluorosis across the geographic areas. The learners erroneously believed that dental fluorosis was due to neglect, which is an indication that many learners are not aware of the cause of dental fluorosis in their community. The general consensus of the communities was that fluorosis was judged with feelings of negativity (embarrassment and a disadvantage for the child into adulthood).
259

Software Defined Networking for Smart Grid Communications

Aydeger, Abdullah 07 July 2016 (has links)
Emerging Software Defined Networking (SDN) technology has provided excellent flexibility to large-scale networks in terms of control, management, security, and maintenance. On the other hand, recent years witnessed a tremendous growth of the critical infrastructure networks, namely the Smart-Grid, in terms of its underlying communication infrastructure. Such large local networks requires significant effort in terms of network management and security. We explore the potential utilization of the SDN technology over the Smart Grid communication architecture. Specifically, we introduce three novel SDN deployment scenarios in local networks of Smart Grid. Moreover, we also investigate the pertinent security aspects with each deployment scenario along with possible solutions. On the other hand, we conducted experiments by using actual Smart Grid communication data to assess the recovery performance of the proposed SDN-based system. The results show that SDN is a viable technology for the Smart Grid communications with almost negligible delays in switching to backup wireless links.
260

Lightweight Middleware for Software Defined Radio (SDR) Inter-Components Communication

Putthapipat, Pasd 11 April 2013 (has links)
The ability to use Software Defined Radio (SDR) in the civilian mobile applications will make it possible for the next generation of mobile devices to handle multi-standard personal wireless devices and ubiquitous wireless devices. The original military standard created many beneficial characteristics for SDR, but resulted in a number of disadvantages as well. Many challenges in commercializing SDR are still the subject of interest in the software radio research community. Four main issues that have been already addressed are performance, size, weight, and power. This investigation presents an in-depth study of SDR inter-components communications in terms of total link delay related to the number of components and packet sizes in systems based on Software Communication Architecture (SCA). The study is based on the investigation of the controlled environment platform. Results suggest that the total link delay does not linearly increase with the number of components and the packet sizes. The closed form expression of the delay was modeled using a logistic function in terms of the number of components and packet sizes. The model performed well when the number of components was large. Based upon the mobility applications, energy consumption has become one of the most crucial limitations. SDR will not only provide flexibility of multi-protocol support, but this desirable feature will also bring a choice of mobile protocols. Having such a variety of choices available creates a problem in the selection of the most appropriate protocol to transmit. An investigation in a real-time algorithm to optimize energy efficiency was also performed. Communication energy models were used including switching estimation to develop a waveform selection algorithm. Simulations were performed to validate the concept.

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