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The relationship between compassion fatigue and coping styles in nurses working in a hospital trauma unitNkosi, Siyabonga Ntokozo Peter-Claver 23 February 2010 (has links)
MA,Clinical Psychology, Faculty of Humanities, University of the Witwatersrand, 2002
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Performance evaluation of unit trusts in South Africa over the last two decadesMibiola, Oluwole Jacob 02 August 2013 (has links)
Thesis (M.M. (Finance & Investment))--University of the Witwatersrand, Faculty of Commerce, Law and Management, Graduate School of Business Administration, 2013. / Unit trust investment looks cosy and attractive from the surface, but a detailed understanding of unit trust and its performance can be daunting. Having discussed the evolution of mutual funds in the US and other industrial and financially sound countries; it is concerning that not much has been done in terms of research works on the South Africa unit trust industry’s performance. Several studies have been aimed at investigating the investment in mutual funds relative to mutual fund returns, but an extensive study on the performance of active unit trusts against their bench-marking index is still lacking. This study contributes to the debate by conducting a detailed study of the performances of mutual funds in the last two decades and also what the global investment fund witnessed over this period, with particular interest in the South African market. Another contribution of this study was to provide reasons for the slow growth of investment funds in South Africa; this study attempts to ascribe reasons as to why this has been so.
This study used three different performance measures (namely: the nominal returns, Sharpe Ratios and CAPM Alphas) to test the possibility of superior performance by the market or the funds. In order to carry out this detailed analysis of the performance of unit trusts, these performance tests were applied individually to the net returns obtained from a sample of 64 South African domestic general equity unit trusts, covering the 20-year period from January 1st 1992 to December 31st 2011. This 20-year period was further divided into 7 different periods of four 5-year periods, two 10-year periods and the whole 20-year period. This was done to avoid survivorship bias. In all of the periods, strong evidence of superior performance by the domestic general equity unit trust over the market could not be found. Furthermore, several reasons were deduced form the study as to investment funds continue to experience slow growth. Some of the reasons include the following: cost of index fund, investor’s sentiments, and commissions amongst others.
Finally, having said all these, outperformance, perhaps may not be the main objective of unit trusts. The findings of this study may not have provided strong evidence of outperformance, it however reveal that there is a need for unit trusts to evaluate the costs and benefits involved in their trading activities in order to provide investors with maximum possible returns for the level of risk they take.
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Estudo das eficiências de operação e consumo de energia em plantas de produção de biodiesel. / Operation efficiency evaluation and energy consumption assessment at a biodiesel production plant.Costa, Regiane Adelina Borella 01 December 2009 (has links)
Este trabalho visa contribuir para o conhecimento dos consumos de energia em uma planta típica de produção de biodiesel. A energia consumida no processo de produção de um combustível deve ser compatível com aquela por ele disponibilizada em suas utilizações. Assim, avaliou-se a energia térmica teórica em kJ/kg envolvida na produção de uma unidade de massa de biodiesel comparando-a com o seu poder calorífico inferior (PCI). Às operações unitárias deste processo, foram aplicados os balanços de materiais e de energia como método para calcular a carga térmica em cada operação para determinar o consumo de energia. Para tanto foi necessário encontrar uma fórmula molecular representativa para o óleo e uma para o biodiesel, com cálculos partindo da massa molar de cada um. A aplicação dos cálculos do balanço de entalpia em algumas operações unitárias dependia dos valores das entalpias de formação do óleo e do biodiesel, que foram calculadas pelo princípio de Hess, através das reações de combustão. O consumo de vapor da planta de biodiesel foi calculado através da massa de vapor consumida em todo o processo sendo comparada com o consumo de biodiesel necessário para a produção desse vapor. O processo analisado consome 25% do biodiesel produzido para gerar suas necessidades de aquecimento, confirmando a utilização do biodiesel como combustível em termos energéticos. / This work aims at contributing to the knowledge of energy consumption in a typical plant of biodiesel production. The energy consumed in the production of fuel must be compatible to the one available in its updating. Therefore, the theoretical thermal energy involved in the production of a biodiesel mass unit in kJ/kg has been evaluated compared to its lower heat value (LHV). To the unitary operations of this process, the balance of materials and energy has been applied as a method to calculate the thermal charge in each operation to determine the energy consumption. To do so, it was necessary to find representative molecular formulas for both oil and biodiesel, with calculations based on the molar mass of each. The application of the calculations of the enthalpy balance in some unitary operations depended on the values of the formation enthalpies of oil and biodiesel, which have been calculated through the principle of Hess, by means of the reactions of combustion. The consumption of steam from the biodiesel plant has been calculated through the steam mass consumed all over the process being compared to the necessary consumption of biodiesel to produce this steam. The analyzed process consumes 25% of the biodiesel produced to generate its heating necessities, confirming the use of biodiesel as fuel in energy terms.
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Characterization of Motor Unit Discharge Rate in Patients with Amyotrophic Lateral SclerosisKasi, Patrick K 04 May 2009 (has links)
In this study, we used a custom made quadrifilar needle electrode and multichannel electromyography (EMG) software tool to decompose EMG signals and investigate the behavior of motor unit discharge rate (MUDR) of concurrently active motor units in patients with amyotrophic lateral sclerosis (ALS). Decomposition is a technique used to break down the complex EMG signal into its constituent motor units. A motor unit is a single alpha motor neuron and all the muscle fibers it innervates. ALS is a progressive degenerative disorder of both the upper and lower motor neurons. We recorded four differentially amplified EMG signals from the first dorsal interosseous (FDI) muscle of six ALS patients (four with predominant lower motor neuron pathology and two with predominant upper motor neuron pathology) and seven control subjects. Recordings were made from force contractions of 20 and 50% of maximum voluntary contraction (MVC). All control subjects were between the ages of 40 and 70 years and were examined by a practicing physiatrist for exclusion criteria including neuromuscular disorders or any medications that might affect muscle activity. We observed differences in initial firing rates and variability of active motor units between control subjects and ALS patients. Furthermore we observed differences in firing rates and variability of active motor units between ALS patients with predominant upper motor neuron pathology and ALS patients with predominant lower motor neuron pathology. Initial motor unit firing rates for control subjects were 16.22 +/- 2.06 Hz at 20% MVC and 19.79 +/- 1.66 Hz at 50% MVC. As expected, initial motor unit firing rates from patients with predominant lower motor neuron pathology were higher than those of control subjects; 18.87 +/- 4.73 Hz at 20% MVC and 24.28 +/- 5.01 Hz at 50% MVC. ALS patients with predominant upper motor neuron pathology, as expected, had initial motor unit firing rates that were lower than those observed in control subjects; 9.22 +/- 1.68 Hz at 20% MVC and 12.83 +/- 2.26 Hz at 50% MVC. Motor unit firing rate time series in ALS patients with predominant upper motor neuron pathology showed decreased variability, 0.99 +/- 0.17 Hz at 20% MVC and 1.70 +/- 0.52 Hz at 50% MVC, when compared to control subjects, 2.37 +/- 0.67 at 20% MVC and 4.20 +/- 1.00 at 50% MVC. Variability of motor unit firing rate time series in ALS patients with predominant lower motor neuron were high, 3.38 +/- 1.2 Hz at 20% MVC and 4.07 +/- 1.56 Hz at 50% MVC, compared to control subjects. At 50% MVC, motor unit substitution was observed in ALS patients with predominant upper motor neuron pathology despite the contractions lasting just a few seconds. Motor unit action potentials (MUAPs) recorded from patients were polyphasic when compared to those from control subjects, as is characteristically found in practice.
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Systemo 5 : an entertainment centerKeithley, Claude A January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Factors influencing the decision to adopt multiple unit franchising arrangementsWeaven, Scott, n/a January 2004 (has links)
Franchising performs an important role in the production and distribution of goods and services. Current research suggests that much of the future growth in franchising in many world economies will be attributable to the growth in multiple unit franchising arrangements. Multiple unit franchising refers to an organisational arrangement in which franchisees are permitted to own more than one unit in the same franchise system. Although the Australian franchising sector has reached an early stage of maturity, the limited acceptance of multiple unit practices contrasts with overseas experiences. This remains a curious anomaly, as significantly higher levels of multiple unit ownership are observable in comparably mature markets in other countries. Multiple unit franchising appears a conceptually unsound alternative to traditional dyadic revenue sharing franchising relationships as it does not benefit from the structural and operational synergies commensurate with ownership attention at the unit level. Therefore, from the franchisor's perspective, multiple unit franchising appears a suboptimal alternative to traditional franchising. From the franchisee's perspective, alternative investment opportunities may present superior choices to multiple unit arrangements. Franchisees have only limited control of their organisation, pay substantial percentages of their gross revenues in the form of fees and royalties, and forgo the ability to capitalise on the growth in the value of their intangible assets. While these apparent disadvantages may be overcome by an individual's desire to 'buy a job', the reasons explaining a franchisee's desire to own multiple units is less clear. Recent research has attempted to explain the ubiquity and increasing popularity of this organisational form, given these operational disadvantages, albeit mostly from the perspective of the franchisor. Previous empirical research in the United States views multiple unit franchising as a driver of system growth, promoting system-wide adaptation to competition. However, this conventional wisdom fails to consider additional franchisor motivational incentives. Moreover, anecdotal evidence in the Australian franchising sector contrasts markedly with the relationships exposed in multiple unit analyses overseas. Thus, existing franchising research does not adequately capture the range of incentives motivating an entrepreneur's decision to elect the franchising channel of distribution. In addition, at this time no theoretical framework exists espousing the reasons that lead to a franchisee's adoption of these hybridised organisational forms. This has led some researchers to conclude that multiple unit franchising is in an embryonic stage. Further complicating our understanding of the choice of this organisational form is the absence of multiple unit incentives analysis in Australia. In addition to gaining valuable insights into current managerial practice, the first purpose of this research is to support informed decision-making in the future through an investigation of the fundamental and under-researched question of why franchisors choose to grow and expand through multiple unit arrangements. This research focuses upon theory development by integrating known concepts with newly identified motivational incentives that caveat the adoption of this organisational arrangement. These incentives are incorporated in a model of multiple unit franchising from the perspective of the franchisor. The model describes multiple unit franchising as a function of the context of franchise system context (age, system corporatisation, plurality of distribution, geographic dispersion of available units and level of existing intra-firm conflict), and strategic (ownership redirection, perceived future agency cost minimisation, and system rewards) factors. In an attempt to extend the cross cultural boundaries of previous franchising research, a given level of multiple unit expansion is described through the predicted outcome of franchise system growth. Secondly, this research investigates the reasons why franchisees become multiple unit holders. This process involved the integration of existing theories drawn from different disciplines and presents an integrated theoretical model explaining why individuals are driven to create their own subsystems within a franchisor-owned network. The multi-perspective approach is critical to advancing our understanding of the genesis of this organisational arrangement, and specifically the issues of who should engage in multiple unit franchising arrangements, and when franchisors and franchisees should sanction and adopt mini-chains within a single franchising system. Thus, this proposal addresses gaps in the literature by investigating the research question: What are the motivational incentives that influence franchisors and franchisees to adopt multiple unit franchising? That is, this thesis aims to identify the reasons that justify the existence of multiple unit franchising forms from the franchisor and franchisee perspectives. A three-stage methodological approach is used in this research. Franchisor motivations are examined within stages one and two. Franchisee motivations are detailed in section three. An examination of the parent disciplines of resource scarcity theory, agency theory, and the immediate discipline of multiple unit franchising resulted in the development of a preliminary conceptual model and general set of propositions explaining why franchisors choose to engage in multiple unit franchising arrangements. In stage one an exploratory survey of seven franchisors from a range of industries of different type, size and age was conducted using a convergent interviewing technique, to gather insights and reasons into multiple unit practices. The stage one findings were used to clarify and confirm the appropriateness of the conceptual model of multiple unit franchising. Permission was granted by the Franchise Council of Australia to include a limited number of questions in the Franchising Australia 2002 survey. In the (second) stage of this research, a sample of the population of franchisors in Australia was surveyed by an electronic questionnaire administered on the World Wide Web in June and July 2002. The resultant data was analysed to test a revised theoretical model of franchisor motivations to adopt multiple unit franchising arrangements. Inferential statistical tests were used to test the relationships hypothesised in the model of multiple unit franchising from the franchisor's perspective. The results built upon the inductive stage of the research, providing a descriptive snapshot of multiple unit franchising in Australia. The third stage of this research explored the factors influencing a franchisee's decision to become a multiple unit owner. Following a review of the predominantly single unit literature, a model and series of general propositions explaining multiple unit franchising was developed explaining multiple unit ownership in terms of subsystem size (expected decision making power and anticipated subsystem economies of scale), franchisee context (franchisee liquidity, entrepreneurial orientation), and strategic (pre-empt future intra-system competition) factors. The appropriateness of the conceptual model and propositions were tested through convergent interviews with ten multiple unit and nine single unit franchisees within a prominent fast-food system. This resulted in a revised conceptual model and general set of propositions that contribute to the development of existing theory and will form the basis of future empirical assessment. This research makes an original contribution to the body of knowledge about multiple unit practice through inductive analysis that not only recognises the reach of this franchising phenomenon, but also develops our theoretical understanding of why franchisors and franchisees engage in intra-firm mini-chain development. So, apart from gaining valuable insight into current managerial motivations and practice in Australia, a concomitant aim of this research is to enhance the generalisability of prior franchising theory developed in the United States through examination of the under-researched areas of why franchisors allow, and franchisees choose, to own more than one unit within the same franchising system. This research has contributed to the body of knowledge on franchising. Based upon the extant literature and exploratory analyses, models of multiple unit franchising from the franchisor and franchisee perspective were developed. It is the first empirical analysis of multiple unit franchising in Australia and provides a starting point for future research. This research has made a valuable contribution in being the first to: investigate multiple unit franchising in an Australian setting using primary data sources; utilise an inductive convergent interviewing technique to clarify and confirm the appropriateness of theories derived from the extant literatures; survey a large representative sample of Australian franchisors about multiple unit franchising; survey a sample of franchisees about multiple unit franchising; incorporate aspects of agency theory, resource constraints theory and multiple unit franchising to develop a model of multiple unit franchising; use a three-stage methodology involving qualitative and quantitative analyses; investigate motivations and factors influencing multiple unit franchising choice; introduce new constructs and reposition existing constructs into multiple unit franchising theory. In conclusion, this original and comprehensive research has found that more experienced Australian franchisors appear to adopt multiple unit franchising, possibly as a method of sustaining growth in units and system-wide sales. Furthermore, entrepreneurial franchisees appear to source private sources of equity in order to grow their holdings sequentially as they anticipate savings accruing from economies of scale while limiting competition within their franchise system.
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Utvärdering av enhetstestning för Palasso / Evaluation of unit testing on PalassoHedman Fallquist, Mattias, Johansson, Fredrik January 2009 (has links)
<p>The market-leading wage and PA-.system for the Swedish public sector Palasso is developed in Karlstad. In order to achieve the highest quality of code , the developing team behind Palasso has been conducting extensive testing. Testing is done to ensure that the software does what it should do. However, the testing has been done at a high level. In order to continue to evolve, the group that develops Palasso has started to look at the new development methods that have become popular in the computer industry in recent years. These methods are based on the use of tests as low as possible so-called unit tests.</p><p>To examine the possibility for Palasso to use unit testing, the study has been divided into two parts. First, a study of existing frameworks to find the best suited one for Palasso. Then, by using the selected framework, a second study is conducted to see if it is possible integrate unit testing with the Palasso system. This part was divided into two methods.</p><p>In the first method a existing functionality was redeveloped to show how the code should be structured and implemented to be suitable for unit tests. In the second method unit testing was introduced on legacy code to prove that it was possible to introduce unit test and that small changes can make the code more testable.</p><p>The best suited framework for Palasso was TestNG. TestNG was chosen because it was easy to use and it had scalability. The second study showed that it is possible to integrate unit tests with the Palasso system. But it should be introduced when new modules are developed or when existing code is modified. The introduction of unit testing provides many advantages. It is concluded that the quality of the Palassos system would benefit from using unit testing.</p> / <p> </p><p>I Karlstad utvecklas det marknadsledande löne- och PA-stytemet för den statliga sektorn Palasso. För att få så hög kvalité på Palasso som möjligt genomförs omfattande testning. Testning genomförs för att säkerställa att mjukvaran gör det den ska göra. Dock har testningen varit på en högre nivå. För att fortsätta utvecklas har gruppen som utvecklar Palasso börjat att snegla på de nya utvecklingsmetoderna som har blivit populära inom dataindustrin de senaste åren. Dessa utvecklingsmetoder bygger på att använda sig av test på så låg nivå som möjligt, så kallade enhetstest.</p><p>För att undersöka möjligheterna för Palasso att använda enhetstest, har två olika delar undersökts av detta arbete. Först genomfördes en studie av de befintliga ramverk som finns för enhetstest. Därefter valdes det ramverk som var bäst lämpad för Palasso. Därefter genomfördes en experimentdel för att se om det var möjligt att införa enhetstest på Palasso. Detta gjordes med det valda testramverket. Denna del delades upp i två metoder. I metod 1 togs en modul av Palasso och skrevs om för att visa på hur koden måste vara uppbyggd för att enhetstestning ska kunna införas. I metod 2 infördes enhetstest på befintlig kod för att bevisa att det var möjligt att införa enhetstest och att små ändringar gör koden mer testbar.</p><p>Det ramverk som valdes till det bäst lämpade för Palasso blev TestNG. Detta för att det var lätt att använda och att det var skalbart. Genom experimentdelen kunde slutsatsen dras att det var möjligt att införa enhetstest på Palasso. Det ska dock införas i samband med nyutveckling eller när ändringar av den befintliga koden ska genomföras. Införandet av enhetstest ger många fördelar därför är slutsatsen att det vore Palassossystemets kvalité till gagn att använda sig av enhetstest.</p>
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Wide-area state estimation using synchronized phasor measurement unitsHurtgen, Michaël 01 June 2011 (has links)
State estimation is an important tool for power system monitoring and the present study involves integrating phasor measurement units in the state estimation process. Based on measurements taken throughout the network, the role of a state estimator is to estimate the state variables of the power system while checking that these estimates are consistent with the measurement set. In the case of power system state estimation, the state variables are the voltage phasors at each network bus.\
The classical state estimator currently used is based on SCADA (Supervisory Control and Data Acquisition) measurements. Weaknesses of the SCADA measurement system are the asynchronicity of the measurements, which introduce errors in the state estimation results during dynamic events on the electrical network.\
Wide-area monitoring systems, consisting of a network of Phasor Measurement Units (PMU) provide synchronized phasor measurements, which give an accurate snapshot of the monitored part of the network at a given time. The objective of this thesis is to integrate PMU measurements in the state estimator. The proposed state estimators use PMU measurements exclusively, or both classical and PMU measurements.\
State estimation is particularly useful to filter out measurement noise, detect and eliminate bad data. A sensitivity analysis to measurement errors is carried out for a state estimator using only PMU measurements and a classical state estimator. Measurement errors considered are Gaussian noise, systematic errors and asynchronicity errors. Constraints such as zero injection buses are also integrated in the state estimator. Bad data detection and elimination can be done before the state estimation, as in pre-estimation methods, or after, as in post-estimation methods. For pre-estimation methods, consistency tests are used. Another proposed method is validation of classical measurements by PMU measurements. Post-estimation is applied to a measurement set which has asynchronicity errors. Detection of a systematic error on one measurement in the presence of Gaussian noise is also analysed. \
The state estimation problem can only be solved if the measurements are well distributed over the network and make the network observable. Observability is crucial when trying to solve the state estimation problem. A PMU placement method based on metaheuristics is proposed and compared to an integer programming method. The PMU placement depends on the chosen objective. A given PMU placement can provide full observability or redundancy. The PMU configuration can also take into account the zero injection nodes which further reduce the number of PMUs needed to observe the network. Finally, a method is proposed to determine the order of the PMU placement to gradually extend the observable island. \
State estimation errors can be caused by erroneous line parameter or bad calibration of the measurement transformers. The problem in both cases is to filter out the measurement noise when estimating the line parameters or calibration coefficients and state variables. The proposed method uses many measurement samples which are all integrated in an augmented state estimator which estimates the voltage phasors and the additional parameters or calibration coefficients.
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Integration of Memory Subsystem with Microprocessor Supporting On-Chip Real Time Trace CompressionLai, Chun-hung 06 September 2007 (has links)
In this thesis, we integrate the memory subsystem, including cache and MMU¡]Memory Management Unit¡^ with the embedded 32 bits microprocessor SYS32TM-II to support the virtual memory mechanism of the operating system and make memory management effectively among multi-processes in the system. To provide the virtual to physical address translation with MMU and to improve the system performance with cache. We reuse the memory subsystem of the LEON2 SoC platform and design the communication interface to coordinate the processor core SYS32TM-II with the LEON2 memory subsystem, and modify the LEON2 memory subsystem to compatible with SYS32TM-II.
After the integration of memory subsystem, a reusing cache for program address trace compression in real time is proposed. The advantage is that reusing cache with minor hardware modification can not only save the hardware compressor overhead but also obtain a high compression ratio. Experimental results show that the proposed approach causes few hardware area overhead but achieves approximately 90% compression ratio at real-time.
Therefore, this thesis is the memory subsystem with parameterized design and with the ability to support system debugging. The role of the memory subsystem is not only to improve the system performance and to provide the hardware support requiring by the operating system, with minor modification, the memory susbsystem can also capture the dynamic program execution trace in parallel with microprocessor. The address trace compression mechanism will not effect the program execution and capable to compress at real-time.
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Investigation in modeling a load-sensing pump using dynamic neural unit based dynamic neural networksLi, Yuwei 15 January 2007
Because of the highly complex structure of the load-sensing pump, its compensators and controlling elements, simulation of load-sensing pump system pose many challenges to researchers. One way to overcome some of the difficulties with creating complex computer model is the use of black box approach to create an approximation of the system behaviour by analyzing input/output relationships. That means the details of the physical phenomena are not so much of concern in the black box approach. Neural network can be used to implement the black box concept for system identification and it is proven that the neural network have the ability to model very complex behaviour and there is a well defined set of neural and neural network structures. Previous studies have shown the problems and limitations in dynamic system modeling using static neuron based neural networks. Some new neuron structures, Dynamic Neural Units (DNUs), have been developed which open a new area to the research associated with the system modelling.<p>The overall objective of this research was to investigate the feasibility of using a dynamic neural unit (DNU) based dynamic neural network (DNN) in modeling a hydraulic component (specifically a load-sensing pump), and the model could be used in a simulation with any other required component model to aid in hydraulic system design. To be truly representative of the component, the neural network model must be valid for both the steady state and the transient response. Due to three components (compensator, pump and control valve) in a load sensing pump system, there were three different pump model structures (the pump, compensator and valve model, the compensator and pump model, and the pump only model) from the practical point of view, and they were analysed thoroughly in this study. In this study, the DNU based DNN was used to model a pump only model which was a portion of a complete load sensing pump. After the trained DNN was tested with a wide variety of system inputs and due to the steady state error illustrated by the trained DNN, compensation equation approach and DNN and SNN combination approach were then adopted to overcome the steady state deviation. <p>It was verified, through this work, that the DNU based DNN can capture the dynamics of a nonlinear system, and the DNN and SNN combination can eliminate the steady state error which was generated by the trained DNN. <p>The first major contribution of this research was in investigating the feasibility of using the DNN to model a nonlinear system and eliminating the error accumulation problem encountered in the previous work. The second major contribution is exploring the combination of DNN and SNN to make the neural network model valid for both steady state and the transient response.
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