Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-24T15:21:43Z No. of bitstreams: 1 Carlos Henrique.pdf: 3192728 bytes, checksum: b409baf77eae63d413fff22f89c2f1d9 (MD5) / Made available in DSpace on 2017-08-24T15:21:43Z (GMT). No. of bitstreams: 1 Carlos Henrique.pdf: 3192728 bytes, checksum: b409baf77eae63d413fff22f89c2f1d9 (MD5) Previous issue date: 2012-11-09 / FAPEMA / Currently, there is growing concern about the Power Quality (PQ) problems due to: introduction of automation in industrial processes, presence of personal computers and electronically controlled devices, load equipments with low capacity to withstand small PQ disturbances and increased perception of residential and industrial consumers with regard to PQ disturbances. In this context, an important issue with relation to PQ is the voltage conformity. That is, the adequacy of service voltage to the limits specified by regulatory agencies. The concern about compliance is due to the following problems caused by sustained undervoltages and overvoltages: improper or less-efficient equipment operation, tripping of sensitive loads, overheating of induction motors due to undervoltages, equipment damage or failure due to overvoltages and higher no-load losses in transformers caused by sustained overvoltages. Furthermore, there have been various incentives for connection of Distributed Generation (DG) in distribution networks due to: incentives for the using of electricity generation based on renewable energy sources and free access of independent energy producers to transmission and distribution networks owing to deregulation of the electric sector. In principle, the voltage profile of a distribution network can be improved with connection of DG. However, it is possible to notice severe deteriorations in the voltage profile of distribution networks in DG post-failure scenarios. These failures are caused by problems in the DG components, such as: cooling system, gears, turbines, etc. During the time period in which the DG is under repair, active and reactive power supports to correct the voltage profile are unavailable. Consequently, the voltage profile tends to deteriorate while the DG is disconnected. In this way, it is important to carry out studies to assess the impact of the DG installation on the voltage conformity indices considering the following issues: DG unavailability after an intrinsic failure and load curve. These aspects are subject to uncertainties due its random nature. Due to this, the most suitable approaches to assess the impact of uncertainties associated with load fluctuations and DG failures on the voltage conformity indices are the probabilistic methods. The main advantage of these methods is its capability to combine severity and probability to truly express the system risk. The main objective of this dissertation is the development of a method that models the random behavior of the distribution network in the voltage conformity indices estimation through the probabilistic methods. Models and techniques to incorporate stochastic variations in the demand and DG unavailability in voltage conformity indices estimation are proposed. The technique proposed in this dissertation to carry a Predictive Assessment of Voltage Conformity (PAVC) is based on the combination of the following techniques: power flow for radial distribution networks via current summation method, Quasi-Sequential Monte Carlo Simulation and Fourier analysis of time series. The PAVC model proposed in this dissertation was tested in 32 buses system. The results obtained with this system demonstrated that the DG has a great potential to improve the voltage conformity indices in the distribution network. However, the most significant improvements in the voltage conformity indices are associated with load points distant from the substation. Furthermore, it can be observed that the uncertainties associated with DG failures cause significant variations in the voltage conformity indices. Additionally, a sensitivity study demonstrated that the voltage conformity indices are worse (better) for systems where the load is modeled as constant power (impedance). / Atualmente há um interesse crescente com relação a problemas de Qualidade de Energia Elétrica (QEE) devido a: introdução de automação em processos industriais; presença de computadores pessoais e dispositivos controlados eletronicamente em instalações residenciais; equipamentos de carga com baixa capacidade para suportar pequenos distúrbios de qualidade de energia; e aumento da percepção dos consumidores industriais e residenciais com relação a distúrbios de QEE. Neste contexto, um aspecto importante com relação a QEE é a conformidade de tensão da rede de distribuição. Ou seja, a adequação da tensão de atendimento aos limites especificados pelos órgãos reguladores. A preocupação com a conformidade de tensão é devido aos seguintes problemas causados por subtensões e sobretensões sustentadas: operação indevida ou com baixa eficiência dos equipamentos elétricos dos consumidores; desligamento de cargas sensíveis; aquecimento de motores de indução devido à subtensões; danos ou falhas em equipamentos devido à sobretensões e aumento nas perdas em vazio nos transformadores causado pela presença de sobretensões sustentadas. Além disso, tem havido diversos incentivos para conexão de Geração Distribuída (GD) na rede de distribuição devido a: incentivo para utilização de sistemas de geração de energia elétrica baseados em fontes de energia renováveis; e livre acesso dos produtores independentes de energia às redes de transmissão e distribuição devido a desregulamentação do setor elétrico. Em princípio, o perfil de tensão de uma rede de distribuição pode ser melhorado com a conexão da GD. Contudo é possível observar deteriorações severas no perfil de tensão de redes de distribuição em cenários pós-falha da GD. Estas falhas são causadas por problemas nos componentes da GD, tais como: sistema de refrigeração, engrenagens, turbina, etc. Durante o período de tempo em que a GD está em reparo, o suporte de potência ativa e reativa da GD, para corrigir o perfil de tensão, está indisponível. Consequentemente, o perfil de tensão tende a se deteriorar enquanto a GD estiver desconectada. Desta forma, é importante realizar estudos para avaliar o impacto da instalação da GD nos índices de conformidade de tensão considerando os seguintes aspectos: indisponibilidade da GD após uma falha intrínseca e a curva de carga. Estes aspectos estão sujeitos a incertezas devido a sua natureza aleatória. Devido a isto, as técnicas mais adequadas para avaliar o impacto de incertezas associadas com flutuações de carga e falhas na GD nos índices de conformidade de tensão são os métodos probabilísticos. A principal vantagem destes métodos é a sua capacidade para combinar severidade e probabilidade para expressar verdadeiramente o risco do sistema. O principal objetivo desta dissertação é o desenvolvimento de um método que modele o comportamento aleatório da rede de distribuição na estimação dos índices de conformidade de tensão através de métodos probabilísticos. Modelos e técnicas para incorporar variações estocásticas na demanda e a indisponibilidade da GD na estimação dos índices de conformidade de tensão são propostos. A técnica proposta nesta dissertação para realizar uma Avaliação Preditiva da Conformidade de Tensão (APCT) se baseia na combinação das seguintes técnicas: fluxo de potência para redes de distribuição radiais via método de soma de correntes; simulação Monte Carlo Quasi-Sequencial e análise de Fourier de séries temporais. O modelo de APCT proposto neste artigo foi testado em um sistema de 32 barras. Os resultados obtidos neste sistema demonstraram que a GD tem um grande potencial para melhorar os índices de conformidade de tensão na rede de distribuição. Contudo, as melhorias mais significativas nos índices de conformidade estão associadas com os pontos de carga mais distantes da subestação. Além disso, pode-se observar que as incertezas associadas com as falhas na GD causam variações significativas nos índices de conformidade de tensão. Adicionalmente, um estudo de sensibilidade demonstrou que os índices de conformidade de tensão são piores (melhores) para sistemas onde a carga é modelada como potência (impedância) constante.

Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-29T13:12:16Z No. of bitstreams: 1 Tiago Silva.pdf: 3175763 bytes, checksum: 8eba0f17a1a1f6fa2606a5235969987e (MD5) / Made available in DSpace on 2017-08-29T13:12:16Z (GMT). No. of bitstreams: 1 Tiago Silva.pdf: 3175763 bytes, checksum: 8eba0f17a1a1f6fa2606a5235969987e (MD5) Previous issue date: 2012-11-09 / CNPQ / The Distributed Generation (DG) can improve the power quality indices associated with Short Duration Voltage Variations (SDVV) due to the reduction in the electric network loading, which in turn causes an improvement in the pre-fault voltage profile. On the other hand, the DG can also deteriorates the power quality indices related to SDVV due to the increasing in the fault currents, which in turns reduce the post-fault voltages. Furthermore, the assessment of the DG impact on SDVV is more difficult with the presence of renewable energy resources. This complexity is due to fluctuations in output power caused by stochastic variations in the primary energy source (sun, wind, tide levels, etc.). Additionally, the bibliographical review on Predictive Assessment of Short Duration Voltage Variations (PAVV) revealed that none of the existing methodology considered the impact of fluctuations in the output power of a wind DG on power quality indices related to SDVV. It was also noticed that the load variations during the study period are ignored in the papers on SDVV. The existence of these deficiencies and the governmental incentives for the use of wind generation motivated this research. The main aim of this dissertation is the development of a methodology for the PAVV capable of recognizing uncertainties associated with wind DG and load fluctuations. The modeling of these uncertainties was carried out using NonSequential Monte Carlo Simulation (MCS). The nodal voltages in the fault scenarios generated by MCS were evaluated using the Admittance Summation Method (ASM) in phase coordinates. The combination of the MCS with the ASM allowed estimating the following indices related to SDVV: the expected value of the SARFI (“System Average RMS – Variation – Frequency Index”) and expected nodal frequency of SDVV. Furthermore, the probability distributions and box plots of the SARFI index have been obtained. The proposed method for the PAVV was tested and validated in a test system with 32 buses. The tests results demonstrated that the DG insertion causes an improvement in the power quality indices associated with SDVV. Additionally, the substitution of conventional DG by wind DG cause a small deterioration in the power quality indices related to SDVV due to fluctuations in the output power of the wind DG. Finally, it was observed that the load fluctuations during the study period cause significant variations in the SARFI index. / A Geração Distribuída (GD) pode melhorar os índices de qualidade de energia associados com as Variações de Tensão de Curta Duração (VTCD) devido a redução no carregamento da rede elétrica, que por sua vez causa uma melhoria no perfil de tensão pré- falta. Por outro lado, a GD também pode degradar os índices de qualidade de energia associados com VTCD devido ao aumento nas correntes de falta, que por sua vez reduzem as tensões pós-falta. Além disso, a avaliação do impacto da DG sobre VTCD é mais difícil com a presença de fontes de energia renováveis. Esta complexidade se deve as flutuações na potência de saída causadas pelas variações estocásticas na fonte de energia primária (sol, vento, níveis de maré, etc.). Adicionalmente, a revisão bibliográfica realizada sobre Avaliação Preditiva de VTCD (APVT) revelou que nenhuma metodologia existente considerou o impacto de flutuações na potência de saída de geradores eólicos nos índices de qualidade referentes às VTCD. Também foi observado que flutuações de carga ao longo do período de estudo são desconsideradas nos artigos sobre APVT. A existência destas deficiências nos métodos de APVT e os incentivos governamentais para o uso de geração eólica motivaram esta pesquisa. O principal objetivo desta dissertação é o desenvolvimento de uma metodologia para a APVT capaz de reconhecer as incertezas associadas com a GD eólica e flutuações de carga. A modelagem destas incertezas na APVT foi realizada através do uso da Simulação Monte Carlo (SMC) não-sequencial. As tensões nodais nos cenários de falta gerados pela Simulação Monte Carlo (SMC) foram calculadas usando-se o Método de Soma de Admitância (MSA) em coordenadas de fase. A combinação da SMC com o MSA permitiu estimar os seguintes índices probabilísticos relacionados com as VTCD: valor esperado do SARFI (“System Average RMS – Variation – Frequency Index”) e frequência nodal esperada de VTCD. Além disso, foram obtidas distribuições de probabilidade e diagramas de caixa associados com o SARFI. O método proposto nesta dissertação para a APVT foi testado em uma rede de distribuição de 32 barras. Os resultados dos testes mostram que a inserção de GD causa uma melhoria nos índices de qualidade associados com as VTCD. Adicionalmente, a substituição de GD convencional por GD eólica causa uma pequena deterioração nos índices de qualidade referentes às VTCD devido as flutuações na potência de saída da GD eólica. Finalmente, também foi observado que as flutuações na carga ao longo do período de estudo causam variações significativas no índice SARFI.

Made available in DSpace on 2016-03-15T19:33:57Z (GMT). No. of bitstreams: 1 Fabiano Stefanoni Redondo.pdf: 528934 bytes, checksum: 8c12328dd5aa339df2c262010954dc47 (MD5) Previous issue date: 2012-09-20 / Certain that has received a review Montesquieu adapting it to the aspirations and social dynamism, so that the division of powers can respond with greater agility and speed expectations of the Company, however, emphasize the need to maintain a fair balance between the powers, fundamental point, to ensure that national and perpetuate democracy; However, we are faced with the political scene, whose Democracy was built based on precepts and fears of a totalitarian recent past, whose effects were perpetuated during the Constituent Assembly and, consequently, the Constitution of 1988 which brought in its wake traces of control and concentration of power primarily to the Executive, with emphasis on the legislative process, and especially with the adaptation of the Institute of decree-Law, Constitutional Law, originating in Brazil in 1937, resumed in 1965 and resurfaced in the mold of Italian decree-law in Federal Brazilian Constitution dated 1988, identified an atrophy of the national legislative power in the legislature; Faced with this scenario, confronted the historical development of the country, both in the doctrinal, legal and social, highlighting the importance of the Legislature for Democracy and proposing, in an attempt at least to minimize the effects of the supremacy of the Executive time as can be observed during the study, this trend is over by proving inevitable media aimed at strengthening the Congress. / Certo que a teoria de Montesquieu tem merecido uma reanálise adequando-a aos anseios e ao dinamismo social, para que a divisão dos poderes consiga responder com maior agilidade e presteza as expectativas da sociedade, no entanto, ressalta-se a necessidade de manter um justo equilíbrio entre os poderes, fundamental ponto, para que garanta e perpetue a democracia nacional. Ao nos deparamos com o cenário político brasileiro, cuja democracia foi construída embasada em preceitos e receios de um passado recente totalitário, cujos efeitos se fizeram perpetuar no decorrer da assembleia constituinte e, consequentemente, na constituição de 1988 que trouxe no seu bojo resquícios de controle e concentração de poder primordialmente para o executivo, com ênfase no processo legislativo e, sobretudo, com a adaptação do instituto do decreto-lei, originário no direito constitucional brasileiro em 1937, retomado em 1965 e ressurgido nos moldes do decreto-legge italiano na constituição de 1988, identificamos uma atrofia do poder normativo no legislativo nacional. Diante de tal cenário, confrontou-se a evolução histórica do país, tanto na esfera doutrinária, legal e social, evidenciando a importância do poder legislativo para a democracia e propondo, na tentativa, ao menos, de minimizar os efeitos da supremacia do executivo, vez que conforme pode ser observado no decorrer do estudo, tal tendência acaba-se por provar inevitável, meios que visem o fortalecimento do congresso nacional.

This thesis presents the RF and mechanical design of a metal-to-metal contact RF MEMS switch. Metal-to-metal contact RF MEMS switches are especially preferred in low frequency bands where capacitive switches suffer from isolation due to the limited reactance. Frequency band of operation of the designed switch is from DC to beyond X-band. Measured insertion loss of the structure is less than 0.2 dB, return loss is better than 30 dB, and isolation is better than 20 dB up to 20 GHz. Isolation is greater than 25 dB below 10 GHz. Hence, for wideband applications, this switch offers very low loss and high isolation. Time domain measurement is necessary for the investigation of the dynamic behavior of the devices, determination of the &lsquo / pull in&rsquo / and &lsquo / pull out&rsquo / voltages of the membranes, switching time and power handling of the devices. Also, failure and degradation of the switches can be monitored using the time domain setup. For these purposes a time domain setup is constructed. Moreover, failure mechanisms of the RF MEMS devices are investigated and a power electronic circuitry is constructed for the biasing of RF MEMS switches. Advantage of the biasing circuitry over the direct DC biasing is the multi-shape, high voltage output waveform capability. Lifetimes of the RF MEMS devices are investigated under different bias configurations. Finally, for measurement of complicated RF MEMS structures composed of large number of switches, a bias waveform distribution network is constructed where conventional systems are not adequate because of the high voltage levels. By this way, the necessary instrumentation is completed for controlling a large scale RF MEMS system.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O objetivo deste trabalho é conhecer e compreender melhor os imprevistos no fornecimento de energia elétrica, quando ocorrem as variações de tensão de curta duração (VTCD). O banco de dados necessário para os diagnósticos das faltas foi obtido através de simulações de um modelo de alimentador radial através do software PSCAD/EMTDC. Este trabalho utiliza um Phase-Locked Loop (PLL) com o intuito de detectar VTCDs e realizar a estimativa automática da frequência, do ângulo de fase e da amplitude das tensões e correntes da rede elétrica. Nesta pesquisa, desenvolveram-se duas redes neurais artificiais: uma para identificar e outra para localizar as VTCDs ocorridas no sistema de distribuição de energia elétrica. A técnica aqui proposta aplica-se a alimentadores trifásicos com cargas desequilibradas, que podem possuir ramais laterais trifásicos, bifásicos e monofásicos. No desenvolvimento da mesma, considera-se que há disponibilidade de medições de tensões e correntes no nó inicial do alimentador e também em alguns pontos esparsos ao longo do alimentador de distribuição. Os desempenhos das arquiteturas das redes neurais foram satisfatórios e demonstram a viabilidade das RNAs na obtenção das generalizações que habilitam o sistema para realizar a classificação de curtos-circuitos. / The objective of this work is to know and understand the unforeseen in the supply of electricity, when there are short duration voltage variations (SDVV). The required databases for the diagnosis of faults were obtained through simulations of a model of radial feeder through software PSCAD/EMTDC. This work uses a Phase-Locked Loop (PLL) in order to detect and perform the estimation SDVV automatic frequency, phase angle and amplitude of the voltage and current from the power grid. This research is developing two artificial neural networks: one to identify and another to locate the SDVV occurred in the distribution system of electricity. The technique proposed here applies to three-phase feeders with unbalanced loads, which can have side extensions triphasic, biphasic and monophasic. In developing the same, it is considered that there is availability of measurements of voltages and currents at the node of the initial feeder and also in some points scattered along the distribution feeder. The performances of the architectures of neural networks were satisfactory and demonstrate the feasibility of ANNs in obtaining the generalizations that enables the system for the classification of short circuits.

Power losses are always a cause of worry for any power grid. In India, the situation is even worse. Though recent reports by Ministry of Power shows that Aggregate Technical and Commercial losses (AT &C losses) have come down from 36.64% in 2002-03 to 27% in 2011-12, yet they are much higher than the losses seen in many of the developed nations. The reduction shown in power loss is because of the Electricity Act, 2003 and the amendments made to it in 2007 which controlled the commercial losses rather than the technical losses. According to Ministry of Power, technical losses (Transmission & Distribution losses or T&D losses) in India are reported to be 23.65% in 2011-12. However, according to the study done by EPRI, for systems deployed in developed countries, these losses are estimated to be in the range of 7-15.5%. T & D losses occur in four system components namely step-up transformers and high voltage transmission (0.5-1%), step down to in intermediate voltage, transmission and step down to sub transmission voltage level (1.5-3%), sub-transmission system and step down to low voltage for distribution (2-4.5%), and distribution lines (3-7%). 1% of power loss is approximately equivalent to annual loss of Rs 600 million for a single state. Hence, in a year, loss in distribution line alone causes approximate loss of Rs 1.8-4.2 billion per state. Understanding and reducing power losses in distribution lines which contribute nearly 50% of the total T&D losses assume significance and has formed the motivation for the work reported in the thesis. In recent years, the trend has been to encourage users to generate solar power predominantly at residential complexes and captive power plants at industrial complexes. It has been suggested in the literature that Distributed Generation (DG) can not only reduce the load demanded from the power grid but also the power loss. In this thesis, it has been shown that by the choice of proper size and location of DG, the power loss can be reduced substantially as compared to unplanned deployment of DGs. The objective of the thesis is to design strategy for location of distributed user generated power to maximize the reduction in power loss. The thesis begins with a study of distributed generation in primary distribution networks and proceeds to problem formulation, with the aim being to develop an algorithm that can find out the optimal locations for DG allocation in a network. A greedy approximation algorithm, named OPLODER (i.e. Optimal Locations for Distributed Energy Resources), is proposed for the same and its performance on a benchmark data set is observed, which is found to be satisfactory. The thesis then moves on to describe the actual data of 101,881 commercial, residential and industrial consumers of Bangalore metropolitan area. A loss model is discussed and is used to calculate the line losses in LV part of the grid and loss is estimated for the said actual data. The detailed analysis of the losses in the distribution network shows that in most cases the losses are correlated with the sanctioned load. However there are also some outliers indicating otherwise. The analysis concludes that the distributed generated sources need to be optimally located in order to benefit fully. Also presented thereafter is a study about the impact of electrical properties and the structure of the network on power loss. In the second part of the thesis, OPLODER was again used to process the BESCOM data of 101,881 consumers by modeling them to be connected in three topologies namely Bus (i.e. linear structure), Star (i.e. directly connected) and Hybrid (i.e. tree structure). In case of Bus topology, when DG capacity available is 5% of the demand in substation, OPLODER reduced the loss from 14.65% to 10.75%, from 11.63% to 7.71% and from 13.33% to 9.24% for IISc, Brindavan, and Gokula substations respectively. Similarly, for the same amount of DG in case of star topology, OPLODER reduced loss from 1.75% to 1.26%, from 3.39% to 2.59% and from 2.96% to 1.99% for IISc, Brindavan, and Gokula substations respectively. Thereafter, the available real world data is re-modeled as a tree-type structure which is closer to the real world distribution network and OPLODER is run on it. The results obtained are similar to those presented above and are highly encouraging. When applied to the three substations viz. IISc, Brindavan and Gokula, the power loss dips from 9.95% to 7.42%, from 6.01% to 4.44% and from 8.07% to 5.95%, in case of DG used is 5% of the demand in substation. For the optimal strategies worked out in the thesis, additional overheads will be present. These overheads are studied and it has been found that the present infrastructure and technologies will be sufficient to handle the smart distribution network and the optimal strategy for distributed sources.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O objetivo deste trabalho é conhecer e compreender melhor os imprevistos no fornecimento de energia elétrica, quando ocorrem as variações de tensão de curta duração (VTCD). O banco de dados necessário para os diagnósticos das faltas foi obtido através de simulações de um modelo de alimentador radial através do software PSCAD/EMTDC. Este trabalho utiliza um Phase-Locked Loop (PLL) com o intuito de detectar VTCDs e realizar a estimativa automática da frequência, do ângulo de fase e da amplitude das tensões e correntes da rede elétrica. Nesta pesquisa, desenvolveram-se duas redes neurais artificiais: uma para identificar e outra para localizar as VTCDs ocorridas no sistema de distribuição de energia elétrica. A técnica aqui proposta aplica-se a alimentadores trifásicos com cargas desequilibradas, que podem possuir ramais laterais trifásicos, bifásicos e monofásicos. No desenvolvimento da mesma, considera-se que há disponibilidade de medições de tensões e correntes no nó inicial do alimentador e também em alguns pontos esparsos ao longo do alimentador de distribuição. Os desempenhos das arquiteturas das redes neurais foram satisfatórios e demonstram a viabilidade das RNAs na obtenção das generalizações que habilitam o sistema para realizar a classificação de curtos-circuitos. / The objective of this work is to know and understand the unforeseen in the supply of electricity, when there are short duration voltage variations (SDVV). The required databases for the diagnosis of faults were obtained through simulations of a model of radial feeder through software PSCAD/EMTDC. This work uses a Phase-Locked Loop (PLL) in order to detect and perform the estimation SDVV automatic frequency, phase angle and amplitude of the voltage and current from the power grid. This research is developing two artificial neural networks: one to identify and another to locate the SDVV occurred in the distribution system of electricity. The technique proposed here applies to three-phase feeders with unbalanced loads, which can have side extensions triphasic, biphasic and monophasic. In developing the same, it is considered that there is availability of measurements of voltages and currents at the node of the initial feeder and also in some points scattered along the distribution feeder. The performances of the architectures of neural networks were satisfactory and demonstrate the feasibility of ANNs in obtaining the generalizations that enables the system for the classification of short circuits.

Text in Afrikaans / Summaries in Afrikaans and English / Bemagtiging van verpleegkundiges in gesondheidsdienste in Suid-Afrika bly 'n voortdurende kwessie en die mate waartoe verpleegbestuur verpleegkundiges bemagtig om outonoom op te tree, is onbekend. Wanneer verpleegkundiges bemagtig is, lei dit tot verbeterde pasientsorg deur middel van verhoogde produktiwiteit en werktevredenheid. Die wyse waarop bemagtiging van verpleegkundiges meet geskied is nog nie in SuidAfrika in diepte ondersoek nie. Die doel van hierdie studie was om daardie elemente wat vir die verpleegbestuurder noodsaaklik is om verpleegkundiges te kan bemagtig, te identifiseer. Deur middel van 'n beskrywende, ontdekkende studie wat van 'n vraelys gebruik gemaak het om inligting te bekom, is die nodige elemente gei'soleer. Verpleegbestuurders in gesondheidsdienste in die Gauteng-area het as teikengroep gedien. Definisies van bestuursbemagtiging is geanaliseer ten einde 'n konseptuele raamwerk te ken saamstel. Ses konsepte het die raamwerk vir hierdie studie gevorm, naamlik: • die bydrae van bestuurstrukture tot die bemagtiging van verpleegkundiges; • die rel van magsdeling in die bemagtiging van verpleegkundiges; • deelnemende besluitneming in die bemagtiging van verpleegkundiges; • die verpleegbestuurder se vaardighede en verantwoordelikhede in haar daaglikse taakontwerp en bestuur wat tot die bemagtiging van verpleegkundiges bydra; • motivering- en beloningstrategiee wat tot bemagtiging bydra; en • eienskappe wat kenmerkend van 'n bemagtigende verpleegbestuurder is. Uit die ontleding van die data het die volgende belangrike elemente ender andere na vore gekom: • Daar behoort gedesentraliseerde verspreiding van mag na die laagste moontlike vlak in die gesondheidsdiens plaas te vind; • Die voorstelle van verpleegkundiges behoort erken en indien aanvaarbaar, geimplementeer te word; • Gesag behoort op so n wyse gedelegeer te word dat onafhanklike besluitneming bevorder word; • Verpleegkundiges se take behoort sodanig ontwerp te word dat onafhanklike optrede in die werkplek bevorder word. Die bevindinge van hierdie studie het getoon dat verpleegbestuurders positief ingestel is betreffende die bemagtiging van verpleegkundiges. Hulle beskou dit as deel van hulle bestuursfunksie. 'n Uitdaging waarmee die bestuurder van die toekoms te kampe sal he, is die van 'n omvattende begrip vir personeellede en om van beheer deur middel van streng burokratiese reels, af te sien. / Empowerment of nurses in health services in South Africa remains an ongoing issue, but the extent to which nursing management empowers nurses to act autonomously is not known. When nurses are empowered patient care and nursing services improve through enhanced productivity and job satisfaction. The way in which nurses could be empowered by management has yet to be addressed by researchers in South Africa. The aim of the present study was to identify those essential elements through which nurse managers can empower nurses. By making use of a descriptive exploratory study, utilizing a questionnaire to acquire the necessary information, the essential elements were isolated. Nurse managers in health services in the Gauteng region formed the target group. Definitions of empowerment in management were analyzed and from this a conceptual framework regarding empowerment was formulated. Six concepts served as the basis of this study: • the contribution of management structures, towards the empowerment of nurses; • the role of power-sharing in the empowerment of nurses; • participative decision making in the empowerment of nurses; • the management skills and responsibilities of the nurse manager in her daily task design and management that contribute to the empowerment of nurses; • motivation and reward strategies that contribute towards empowerment; • attributes which characterise an empowered nurse manager. From the analysis of. the data the following important elements among others emerged: • Decentralization of the distribution of power to the lowest possible level should take place in the health services; • The suggestions of nurses should be acknowledged and if found acceptable, to be implemented; • Authority should be delegated in such a way that independent decision making by nurses is enhanced; • Nurses' tasks should be designed in a way that promote independent performance in the work place. The findings of this study revealed that nurse managers are favourably disposed towards the empowerment of nurses. They see this as part of their managerial function. A challenge which confronts the manager of the future is that of comprehensively understanding staff members, and setting aside control through bureaucratic behaviour. / Health Studies / D. Litt. et Phil.

This study of contemporary jazz discourse and gender applies the techniques of critical discourse analysis, inspired by M.A.K. Halliday's systemic functional linguistics and Norman Fairclough's qualitative critical discourse analysis, to explicate the unequal distribution of power in society as represented by the institutions of jazz and mass media, in discourse about jazz vocal artists. Specifically, the study focuses on the way the genres of jazz CD review, jazz performance review, and interviews with jazz artists – disseminated via the institutions JazzTimes and Live New Orleans – represent the artists' identities, roles, achievements and skills. Following Norman Fairclough and the feminist scholar Mary Talbot, the study assumes that institutions of mass media not only discursively construct the gender of jazz vocal artists, but also represent the performers' achievement and skills from a hegemonic standpoint, reflecting the commonsense assumptions about women and men and their roles in patriarchal society.

Text in Afrikaans / Summaries in Afrikaans and English / Bemagtiging van verpleegkundiges in gesondheidsdienste in Suid-Afrika bly 'n voortdurende kwessie en die mate waartoe verpleegbestuur verpleegkundiges bemagtig om outonoom op te tree, is onbekend. Wanneer verpleegkundiges bemagtig is, lei dit tot verbeterde pasientsorg deur middel van verhoogde produktiwiteit en werktevredenheid. Die wyse waarop bemagtiging van verpleegkundiges meet geskied is nog nie in SuidAfrika in diepte ondersoek nie. Die doel van hierdie studie was om daardie elemente wat vir die verpleegbestuurder noodsaaklik is om verpleegkundiges te kan bemagtig, te identifiseer. Deur middel van 'n beskrywende, ontdekkende studie wat van 'n vraelys gebruik gemaak het om inligting te bekom, is die nodige elemente gei'soleer. Verpleegbestuurders in gesondheidsdienste in die Gauteng-area het as teikengroep gedien. Definisies van bestuursbemagtiging is geanaliseer ten einde 'n konseptuele raamwerk te ken saamstel. Ses konsepte het die raamwerk vir hierdie studie gevorm, naamlik: • die bydrae van bestuurstrukture tot die bemagtiging van verpleegkundiges; • die rel van magsdeling in die bemagtiging van verpleegkundiges; • deelnemende besluitneming in die bemagtiging van verpleegkundiges; • die verpleegbestuurder se vaardighede en verantwoordelikhede in haar daaglikse taakontwerp en bestuur wat tot die bemagtiging van verpleegkundiges bydra; • motivering- en beloningstrategiee wat tot bemagtiging bydra; en • eienskappe wat kenmerkend van 'n bemagtigende verpleegbestuurder is. Uit die ontleding van die data het die volgende belangrike elemente ender andere na vore gekom: • Daar behoort gedesentraliseerde verspreiding van mag na die laagste moontlike vlak in die gesondheidsdiens plaas te vind; • Die voorstelle van verpleegkundiges behoort erken en indien aanvaarbaar, geimplementeer te word; • Gesag behoort op so n wyse gedelegeer te word dat onafhanklike besluitneming bevorder word; • Verpleegkundiges se take behoort sodanig ontwerp te word dat onafhanklike optrede in die werkplek bevorder word. Die bevindinge van hierdie studie het getoon dat verpleegbestuurders positief ingestel is betreffende die bemagtiging van verpleegkundiges. Hulle beskou dit as deel van hulle bestuursfunksie. 'n Uitdaging waarmee die bestuurder van die toekoms te kampe sal he, is die van 'n omvattende begrip vir personeellede en om van beheer deur middel van streng burokratiese reels, af te sien. / Empowerment of nurses in health services in South Africa remains an ongoing issue, but the extent to which nursing management empowers nurses to act autonomously is not known. When nurses are empowered patient care and nursing services improve through enhanced productivity and job satisfaction. The way in which nurses could be empowered by management has yet to be addressed by researchers in South Africa. The aim of the present study was to identify those essential elements through which nurse managers can empower nurses. By making use of a descriptive exploratory study, utilizing a questionnaire to acquire the necessary information, the essential elements were isolated. Nurse managers in health services in the Gauteng region formed the target group. Definitions of empowerment in management were analyzed and from this a conceptual framework regarding empowerment was formulated. Six concepts served as the basis of this study: • the contribution of management structures, towards the empowerment of nurses; • the role of power-sharing in the empowerment of nurses; • participative decision making in the empowerment of nurses; • the management skills and responsibilities of the nurse manager in her daily task design and management that contribute to the empowerment of nurses; • motivation and reward strategies that contribute towards empowerment; • attributes which characterise an empowered nurse manager. From the analysis of. the data the following important elements among others emerged: • Decentralization of the distribution of power to the lowest possible level should take place in the health services; • The suggestions of nurses should be acknowledged and if found acceptable, to be implemented; • Authority should be delegated in such a way that independent decision making by nurses is enhanced; • Nurses' tasks should be designed in a way that promote independent performance in the work place. The findings of this study revealed that nurse managers are favourably disposed towards the empowerment of nurses. They see this as part of their managerial function. A challenge which confronts the manager of the future is that of comprehensively understanding staff members, and setting aside control through bureaucratic behaviour. / Health Studies / D. Litt. et Phil.