Thesis (Ph.D.)--Technischen Universität Berlin, 2001. / Includes bibliographical references (leaves 195-201). Also available on the Internet via the World Wide Web.

The cost of health care services is rising and the number of patients requesting overseas treatment from the Kuwait Government continues to increase; this is becoming an unsustainable financial burden. A telemedicine system has the potential to support the Kuwaiti health system to provide medical consultations from global medical centres, and thereby reduce the number of Kuwaiti patients being sent abroad for treatment, and so reduce costs. This research investigates the readiness of the key stakeholders in regard to adoption of telemedicine systems in the Kuwaiti healthcare system. This is achieved by assessing the readiness of individuals (physicians and patients), the organisation (policy makers) and the technical infrastructure (IT managers). Moreover, the lack of research on this topic, particularly in the Arabian Gulf Region, was the reason behind carrying out this study. An in-depth study was conducted by using a quantitative and qualitative approach. A questionnaire was used to explore the attitudes of specialised physicians and patients by obtaining their opinions based on specific criteria. Next, semi-structured interviews were conducted: (1) with IT managers to assess the technical infrastructure of the health system; and (2) with policy makers to assess the organisation in regard to its readiness towards telemedicine adoption. The study shows that the overseas referral patients are ready to use telemedicine systems, as a consequence of their need to receive medical consultations from global experts. However, they expressed some concerns, such as privacy and confidentiality of their data. The specialised physicians also showed readiness towards adoption of telemedicine in the Kuwaiti health system, and their responses indicated that they are willing to use such systems. However, the findings of the interviews reveal that the current technical infrastructure for ICT in the Kuwaiti healthcare system is not ready for telemedicine adoption and there are needs to be change in the way management is organized in order to improve and enhance trust among departments. The qualitative approach identified factors that would inhibit and hinder the adoption of telemedicine in Kuwait, as well as the supportive factors in the organisation. Using the results, a strategy was developed to demonstrate how the Kuwaiti health system could be made ready to receive a telemedicine system, together with policies for the use of telemedicine systems by overseas referral patients. A comparison with Jordan and Syria shows that the Kuwaiti healthcare system is more ready to adopt a telemedicine system with respect to the individuals, technical infrastructure and governmental support. Finally, an economic analysis was performed in order to investigate the cost effectiveness of the proposed system.

M. Tech. (Electrical, Applied Electronics and Electronic Communication, Faculty of Engineering and Technology) Vaal University of Technology| / The demand for efficient and environmentally friendly power sources has become a major topic around the world. This research explores the capability of the zinc-air fuel cell to replace conventional power sources for various applications, more specifically telecommunication systems. The research consisted of a theoretical study of the zinc-air fuel cell and its components, as well as their performance characteristics. A zinc-air fuel ce.ll and test rig were built, and the system was tested under various conditions. It was found that the zinc-air fuel cell has an advantage over other fuel cells in that it does not require any expensive materials or noble metals, reducing the overall cost of such a system. The fuel cell showed the potential to power various applications, but problems persisted in the fueling process as well as constant leaking of the aqueous electrolyte.

Made available in DSpace on 2016-08-10T10:40:26Z (GMT). No. of bitstreams: 1 Bruno Quirino de Oliveira.pdf: 3736663 bytes, checksum: e1dc08656b351b56c485c6f1ee09217b (MD5) Previous issue date: 2015-03-12 / Telecommunications experience accelerated evolution. The environment is very competitive and the volume of financial resources involved is significant. The variety of available technologies makes system planning stage, a procedure not only desirable but necessary, especially in a competitive environment. The use of comprehensive and flexible methodologies that can assist in decision-making, based on mathematical optimization models, it seems an inevitable way. This paper presents mathematical models based on operational research, mixed integer linear programming (MILP) and fuzzy logic to assist in strategic planning and decision-making, for the telecommunications industry, where they are analyzed, discussed and applied optimization models approach node-arc and arc-path. The analysis is focused on minimizing the cost given the expected demand. The main network components, services and costs are identified and models are developed to determine the network configuration or service. The models allow for greater flexibility and a high degree of interaction with the planner. These characteristics make it possible to analyze various scenarios where there is inaccuracy, both for the selection of services and for network deployment. To ensure the practical validation of the methodology, results of computational experiments are presented and discussed. Noteworthy are the results: (1) the possibility of holding a multi-service planning, with the possibility of assigning priorities in the services and care (2) effectiveness of the model for network deployment, which revealed a gain of 2% in the optimal solution in a test instance of SNDlib repository. / As telecomunicações experimentam acelerada evolução. O ambiente é muito competitivo e o volume de recursos financeiros envolvidos é significativo. A variedade de tecnologias disponíveis faz da etapa de planejamento do sistema um procedimento não só desejável como necessário, principalmente num ambiente de competitividade. A utilização de metodologias abrangentes e flexíveis que possam auxiliar no processo de decisão, fundamentadas em modelos matemáticos de otimização, parece um caminho inevitável. Este trabalho apresenta modelos matemáticos baseados em pesquisa operacional, programação linear inteira mista (PLIM) e lógica fuzzy para ajudar no planejamento estratégico e na tomada de decisões, para o setor de telecomunicações, onde são analisados, aplicados e discutidos modelos de otimização com abordagem nó-arco e arco-caminho. A análise é orientada à minimização do custo atendendo a demanda prevista. Os principais componentes de rede, de serviços e de custos são identificados e os modelos são desenvolvidos para determinar a configuração de rede ou de prestação de serviços. Os modelos permitem uma maior flexibilidade e um alto grau de interação com o planejador. Estas características possibilitam analisar variados cenários onde há imprecisão, tanto para a seleção de serviços, quanto para a implantação de rede. Para garantir a validação prática da metodologia desenvolvida, resultados de experimentos computacionais são apresentados e discutidos. Destacam-se nos resultados: (1) a possibilidade de realizar um planejamento multi-serviço, com possibilidade de atribuir prioridades no atendimento dos serviços e (2) eficácia do modelo, para a implantação de rede, onde se obteve um ganho de 2% na solução ótima, em uma instância de teste do repositório SNDlib.

Orientador: Helio Waldman / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T21:18:47Z (GMT). No. of bitstreams: 1 Magro_JulioCesar_M.pdf: 1795144 bytes, checksum: cc5adfc75b6040f36e37ce144569c2be (MD5) Previous issue date: 2005 / Resumo: Este trabalho descreve o estudo da qualidade de voz em redes IP a partir de uma revisão dos protocolos e mecanismos relativos a qualidade de serviço (QoS) e os aspectos do impacto sistêmico na presença ou ausência destes; revisão dos diversos métodos de avaliação da qualidade da voz com ênfase nos métodos automáticos (objetivos e repetitivos) para auxiliar na análise dos efeitos na voz dos diversos fatores presentes em uma rede de pacotes, tais como perda de pacote, atraso e jitter, bem como a própria codificação da voz em baixas taxas; revisão dos principais protocolos de sinalização utilizados para implementação de voz sobre IP (VoIP) ou telefonia sobre IP, evidenciando-se seus pontos fortes e fracos com relação a facilidade de implementação, extensibilidade e adequabilidade para várias aplicações de rede e qualidade de serviço (QoS) e realização de testes em redes IP simulada e experimental. O principal objetivo é a caracterização do serviço de voz em redes IP levando-se em consideração os efeitos dos fatores de rede e gateway no tempo de estabelecimento de uma chamada (conexão) e na qualidade da voz. Para simulação da rede IP foi utilizado o software Cloud da Shunra onde é possível tratar, de forma isolada, a influência da perda de pacote, do atraso fixo, do atraso variável (jitter), bem como do efeito conjunto da perda de pacote e jitter. Soluções a tais efeitos são investigadas em testes experimentais. Resultados de simulações sistêmicas são apresentados e discutidos. As degradações na voz devidas a tais efeitos são avaliadas e um método prático para solucionar é testado. Os resultados experimentais demonstram a viabilidade técnica da utilização da voz sobre IP (ou telefonia IP) pelos provedores de serviço, bem como pelas corporações privadas, podendo trafegar voz e dados em uma mesma rede convergente IP / Abstract: This work describes the study of voice quality in IP networks based on a revision of quality of service (QoS) protocols and mechanisms and aspects of the system impact associated with the presence or absence of them; revision of the diverse evaluation methods of voice quality with emphasis in the automatic methods (objective and repetitive) used to analyze the effects in the voice due to diverse factors presented in packet networks, such as packet loss, delay and jitter, as well as the proper voice coding at low rate; revision of the main protocols of signalling for implementation of voice over IP (VoIP) or IP telephony, considering its strong and weak points with regard to implementation facility, scalability and adequacy for some network applications and quality of service (QoS) and accomplishment of tests in simulated and experimental IP networks. The main objective is the characterization of voice service in IP networks taking into account the effect of the network factors in call set-up (connection) and in voice quality . For the simulation of the IP network the Shunra¿s Cloud software was used where it is possible to deal with, in isolated form, the influence of packet loss, fixed delay, delay variation ( jitter), as well as the composed effect of packet loss and jitter. Solutions to such effects are investigated in experimental tests. Results of system simulations are presented and discussed. Degradations in voice due to such effects are evaluated and a practical method to solve them is considered. The experimental results demonstrate the technical feasibility of using voice over IP (or IP telephony) by service providers, as well as private corporations being able to forward voice and data over the same converged IP network / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Abstract in English, Afrikaans and Zulu / The aim of this study was to determine the key factors which explain the adoption of mobile data services in South Africa and incorporate them into an explanatory framework that can be used to indicate whether a new mobile data service that is introduced into the South African Mobile Market will be successful. Additionally, it shows that the current usage of mobile data services in South Africa supports the framework. The research used a design based on a mixed methods methodology. The research was conducted using a literature survey and two research phases. The literature survey was an extensive review of communication technology adoption frameworks and all the possible factors of adoption. This literature survey was also used to develop the discussion document which was used as the guidelines for the Phase 1 interviews. The interviews were with experts in the telecommunications market in South Africa and were used to determine the key drivers of adoption and possible moderating factors of mobile data services. From those interviews a preliminary model was proposed. Phase 2 was a market survey which tested the framework and moderating factors in different metropolitan areas as well as examined the current usage of mobile data services. The statistical analysis used in determining the framework incorporated Descriptive Statistics, Factor Analysis, using Principal Axis Factoring, and Structural Equation Modelling. The framework, which was based on the Technology Acceptance Model, introduced two new constructs. The first new construct was the Mobile Service Providers Marketing Tactics and the second was Social Pressure and Aspirational Value. The two constructs combined can be used to explain why mobile service providers with low cost strategies are not successful. Demographic factors such as Age were found to influence the adoption as well as Socio-economic factors such as Income. Personal factors such as Technical Knowledge, Ability and Skills and Attitude towards Technology were also found to influence adoption. Geographical location was found to be the most important moderating factor. The current mobile data usage supported the framework. The results of data usage highlighted the fact that nearly 50% of the study’s participants spent over 4 hours per day interacting with their mobile devices and that the participants from Gauteng spent more than 2½ times on mobile services than those in the other metropolitan municipalities of Cape Town and eThekwini / Die doel van hierdie studie was om die sleutelfaktore te bepaal wat die aanneming van selfoondatadienste in Suid-Afrika verklaar, en hulle te verenig in ʼn raamwerk waarmee aangetoon kan word of ʼn nuwe selfoondatadiens die Suid-Afrikaanse selfoondatamark suksesvol sal betree. Afgesien hiervan dui hierdie studie aan dat die huidige gebruik van selfoondatadienste in Suid-Afrika die geldigheid van die voorgestelde raamwerk bevestig. ʼn Mengsel van metodes is in die navorsing toegepas. Die navorsing het uit ʼn literatuuroorsig en twee navorsingsfases bestaan. Die literatuuroorsig het ʼn deurtastende oorsig van die raamwerke vir die aanneming van kommunikasietegnologie en alle moontlike faktore daarvoor behels. Uit die literatuuroorsig is die besprekingsdokument saamgestel wat as riglyn gedien het vir die onderhoude in fase 1 van die navorsing. Onderhoude is met kundiges uit die Suid-Afrikaanse telekommunikasiebedryf gevoer om die belangrikste dryfvere vir aanneming en moontlike remfaktore ten opsigte van selfoondatadienste te bepaal. ʼn Voorlopige model is op grond van die onderhoude aangebied. Fase 2 het ʼn markopname behels waarin die raamwerk en remfaktore in verskeie metropolitaanse gebiede getoets en die huidige gebruik van selfoondatadienste ondersoek is. Die statistiese analise waarop die raamwerk berus, het bestaan uit beskrywende statistiek, faktorontleding met behulp van hoofasfaktorering, en struktuurvergelykingsmodellering. Twee nuwe konstrukte het uit die raamwerk wat op die tegnologieaanvaardingsmodel gegrond was, gespruit. Die eerste was selfoondiensverskaffers se bemarkingstrategieë en die tweede sosiale druk en aspirerende waarde. Saam verklaar die twee konstrukte waarom selfoondiensverskaffers wat laekostestrategieë volg, misluk. Daar is bevind dat demografiese faktore soos ouderdom, en sosiaal-ekonomiese faktore soos inkomste, aanneming beïnvloed. Volgens die bevindings word aanneming eweneens bepaal deur persoonlike faktore soos tegniese kennis, vermoë en vaardighede asook houding jeens tegnologie. Daar is bevind dat geografiese ligging die belangrikste remfaktor is. Die huidige selfoondatagebruik bevestig die geldigheid van die raamwerk. Die uitslag van datagebruik benadruk die feit dat byna 50% van die deelnemers aan die studie langer as vier uur per dag met hulle selfone doenig is, en dat deelnemers in Gauteng twee en half keer meer as deelnemers in die metropolitaanse munisipaliteite van Kaapstad en eThekwini aan selfoondienste bestee. / Inhloso yalolu cwaningo bekuwukuthola izinto ezibalulekile ezichaza ukwamukelwa kwezinsiza zamadatha amaselula eNingizimu Afrika nokuzifaka ohlakeni oluchazayo olungasetshenziswa ukukhombisa ukuthi ngabe insiza entsha yedatha ethulwe emakethe yamaselula eNingizimu Afrika izophumelela. Ngaphezu kwalokho, kukhombisa ukuthi ukusetshenziswa kwamanje kwezinsiza zedatha yamaselula eNingizimu Afrika kuyalusekela uhlaka. Ucwaningo lusebenzise umklamu osuselwe ezindleleni zokwenza ezixubile. Ucwaningo lwenziwe kusetshenziswa ucwaningo lwezincwadi kanye nezigaba ezimbili zocwaningo. Ucwaningo lwezincwadi belungukubuyekezwa okubanzi kokwamukela kwenzinhlaka zobuchwepheshe kwezokuxhumana kanye nazo zonke izici ezingenzeka ukuthi zamukelwe. Lolu cwaningo lwezincwadi lusetshenzisiwe futhi ukuthuthukisa umqulu wezingxoxo osetshenziswe njengezinkombandlela zokuxoxisana nabantu besigaba 1. Izingxoxo ebezinazo bezingochwepheshe emakethe yezokuxhumana eNingizimu Afrika futhi zasetshenziselwa ukuthola izidingongqangi zokwamukelwa kanye nezici zokulingisanisa kwezinsiza zamadatha amaselula. Kulezo zingxoxo, kuphakanyiswe isifaniselo sokuqala. Isigaba 2 bekungukucwaningo lwezimakethe oluhlola uhlaka kanye nezici zokulinganisa ezindaweni ezahlukahlukene zedolobha kanye nokuhlola ukusetshenziswa kwamanje kwezinsiza zedatha yamaselula. Ukuhlaziywa kwezibalo okusetshenzisiwe ekunqumeni uhlaka lufake izibalo ezichazayo, ukuhlaziya izakhi, kusetshenziswa izisekelo eziyinhloko zokuphamba, kanye nesifaniselo sokulinganisa esihlelekile. Uhlaka, olwalususelwa kusifaniselo sokwamukela ubuchwepheshe, lwethule izakhiwo ezimbili ezintsha. Isakhiwo esisha sokuqala kwakungamacebo wokukhangisa wabahlinzeki bezinsiza zamaselula futhi owesibili kwakuyingcindezi yomphakathi nenani lesifiso. Lezi zakhiwo zombili ezihlanganisiwe zingasetshenziswa ukuchaza ukuthi kungani abahlinzeki bezinsizakalo zamaselula abanamasu ezindleko eziphansi bengaphumeleli. Izici ezithinta abantu ezinjengobudala zitholakele ukuthonya ukwamukelwa kanye nezici zezomnotho nezenhlalo ezifana nomholo. Izici ezithinta umuntu ngqo ezifana nolwazi lwezobuchwepheshe, ukwazi ukwenza kanye namakhono, nesimo sengqondo maqondana nezobuchwepheshe zatholakala zithonya ukwamukelwa. Indawo yendawo yatholakala njengesici sokulinganisa esibaluleke kakhulu. Ukusetshenziswa kwedatha yeselula yamanje kusekele uhlaka. Imiphumela yokusetshenziswa kwedatha igcizelele iqiniso lokuthi bacishe babe ngama-50% ababambe iqhaza kulolu cwaningo bachithe isikhathi esingaphezu kwamahora amane ngosuku bexhumana nemishini yabo yamaselula nokuthi ababambiqhaza abavela eGauteng bachithe izikhathi ezingaphezu kwezingu-2½ kuzinsiza zamaselula kunalabo bakwamanye amadolobha amakhulu aseKapa naseThekwini. / Business Management / D.B.L.

La presente tesina consiste en el diseño de migración de nodos B aplicado para una RNC caída de una red móvil, con la finalidad de solucionar los problemas que se presenten ante un incidente que afecte los servicios de voz y datos de los usurarios de una red móvil. En el desarrollo de la tesina, se describe el planteamiento del problema, el marco teórico de la tecnología UMTS y posteriormente nos centramos en los elementos principales de esta tecnología. También describimos los equipos importantes a utilizar en desarrollo del proyecto, en este caso nos enfocamos en la descripción de la RNC. Y finalmente describimos el desarrollo del proyecto, el diseño de la solución e implementación de la misma, y en donde se presentan los resultados del diseño. This thesis is the design of migration of nodes B and its a applied when RNC fall for a mobile network, in order to solve the problems that arise before an incident affecting voice and data services from a mobile network. In developing the thesis, we describe the theoretical framework of UMTS technology and then we focus on the main elements of this technology. We also describe the important equipment used in project development; in this case we focus on the description of the RNC. And finally we describe the solution of design and implementation .Also, the results of this project.