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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.
1

The Impact of Knowledge Management System Usage on Organizational Capability and Organizational Performance

Chen, Yi-hsiang 09 September 2010 (has links)
In this knowledge explosion environment, knowledge management systems increasing organizational capability and performance.This research investigates play an important role in relationships among several major factors: service quality, knowledge management system quality (include System Quality and Content Quality), system usage, organizational capability (include Agility and Innovativeness) and organizational performance. An empirical study was performed to examine their relationships. The findings show significant positive relation among Service Quality, Knowledge Management System Quality and System Usage; System Usage and Organizational Capability, and Organizational Capability and organizational performance.The result is consistent with existing literature to support the value of knowledge management systems.
2

Analyzing The System Usage of ERP system From Multilevel Perspective

Yang, Wan-yu 02 July 2009 (has links)
none
3

EFICIÊNCIA DOS SISTEMAS DE APROVEITAMENTO DAS ÁGUAS PLUVIAIS NA REGIÃO CENTRAL DO RIO GRANDE DO SUL / THE EFFICIENCY OF RAINWATER USAGE SYSTEMS IN THE CENTRAL REGION OF RIO GRANDE DO SUL

Seeger, Lília Mayumi Kaneda 05 December 2008 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work shows a study about the system efficiency of rainwater s usage in the central region of Rio Grande do Sul and it aims to evaluate the utilization of not potable waters´ potential that come from impermeable surfaces. The hydrological potential was classified very good, considering pluvial sources (rainwater) from 30 regions' station, with historical series higher than 15 years. The activities to exploitation and its respectively demands were chosen, determining the efficiency of the system usage, with the use of different areas of captation and commercial volumes of rainwater tanks. The volumetric reliability was calculated in single-family house with the use of daily and monthly precipitation from the historic series of Santa Maria (code 02953034), volumes of 10, 12 and 20 m³ and areas of 70, 100, 150, 200 and 300 m². It was verified that the use of daily or monthly sources (datas) of precipitation conducted to nearest results. There are coincidences to minimum values, including in the dimension of the area s captation and the volume of storage. However, it was observed that to maximum reliability, the volume s results and the areas are bigger when monthly sources (datas) were used. In order to compare the sources, it was analyzed the efficiency applying volumes of water tanks determined by Kobiyama and Hansen Method (2002) to Cacequi´station (code 02954001). In this case, it was also determinated the captation s area that resulted in better volumetric reliability. The comparative analysis between the studied stations showed that there is a significant efficiency s development in function to the increase of the area of captation to the same volume of storage in comparison to a small variation of efficiency to the enlargement to the volume of a constant area. The methodology in this study offers an interconnected vision of the influence of the different constituents of the system usage, simulating the behavior of the system as a whole. The demands of single-family house with area of 70 m2 and water tanks of 500 L the minimum of efficiency found was 20% and the maximum was 28.33%. To multi-store building with area of 300 m² and 15000 L of reservoir s volume, the minimum was 10% and the maximum was 17.33%. In Gas Stations with 1000 m² of area and volume of 20000 L, the minimum volume was 40% and the maximum 58%. In beer s industry with area of 7000 m² and reservoir volume of 20000 L, the results showed minimum of 25% and maximum of 38.65¨%. The method presented makes possible the graphic visualization of the efficiency to be obtained in the usage systems to determine captation area, rainwater tanks volume and the implemented demands. It also allowed to verify the dimension to be projected in relation to captation s area and the volume of storage, since the demands has been determinated to reach and determine the intended efficiency. The equation s adjustment to the reservoir s sizing was obtained from a R2 coefficient adjustment of 0.9925 and from Nash coefficient of 0.9914. The criteria showed and discussed revealed adequate, resulting in efficiencies quite satisfactory to partial demands to not potable waters in the analyzed cities. / Este trabalho apresenta um estudo da eficiência do sistema de aproveitamento das águas pluviais na região central do Rio Grande do Sul e tem como objetivo geral avaliar o potencial de aproveitamento para fins não potáveis de águas provenientes de superfícies impermeáveis. O potencial hidrológico foi classificado considerando os dados pluviométricos de 30 estações da região, com séries históricas superiores a 15 anos e resultou Muito Bom . As atividades para aproveitamento e suas respectivas demandas foram escolhidas, determinando-se a eficiência do sistema de aproveitamento, com a utilização de diferentes áreas de captação e volumes comerciais de reservatórios. A confiabilidade volumétrica foi calculada em residência unifamiliar com a utilização de precipitações diárias e mensais da série histórica de Santa Maria (código 02953034), volumes de 10, 12 e 20 m³ e áreas de 70, 100, 150, 200 e 300 m². Foi verificado que o uso de dados diários ou mensais de precipitação conduziu a resultados próximos. Para valores mínimos há uma coincidência, inclusive, nas dimensões da área de captação e volume de armazenamento. Entretanto, para confiabilidade máxima observa-se que os resultados de volumes e áreas são maiores quando do uso de dados mensais. Por critérios comparativos procedeu-se, também, a análise da eficiência com o emprego de volumes de reservatório determinados pelo método de Kobiyama e Hansen (2002) para a estação de Cacequi (código 02954001). Neste caso, determinou-se também, as áreas de captação que resultavam em melhor confiabilidade volumétrica. A análise comparativa entre as estações estudadas demonstrou que existe um crescimento mais significativo da eficiência em função do aumento da área de captação para um mesmo volume de armazenamento em comparação a uma menor variação da eficiência para um aumento do volume a uma dada área constante. A metodologia proposta oferece uma visão interligada da influência dos diferentes constituintes do sistema de aproveitamento, simulando o comportamento deste como um todo. Para a demanda em residências unifamiliares com área de 70 m² e volume do reservatório de 500 L a eficiência mínima encontrada foi 20% e a máxima de 28,33%. Já para residências multifamiliares com área de 300 m² e volume de 15000 L a mínima foi de 10% e a máxima de 17,33%.. Nos postos de combustíveis com área de 1000 m² e volume de 20000 L o valor mínimo foi de 40% e o máximo de 58%. Em indústria de cerveja com área de 7000 m² e volume do reservatório de 200000 L os resultados demonstraram um mínimo de 25% e máximo de 38,65%. O método apresentado possibilita a visualização gráfica da eficiência a ser obtida nos sistemas de aproveitamento para determinada área de captação, volume de reservatório e demanda já implantada. Permite ainda, verificar as dimensões a serem projetadas em termos de área de captação e volume de armazenamento, conhecida a demanda, para que se consiga atingir uma determinada eficiência pretendida. O ajuste da equação para dimensionamento do reservatório foi obtido para um coeficiente de ajuste R2 de 0,9925 e Coeficiente de Nash de 0,9914. Os critérios apresentados e discutidos mostraram-se adequados resultando em eficiências consideravelmente satisfatórias ao atendimento parcial das demandas para fins não potáveis nos municípios analisados.
4

New Perspectives on the System Usage Construct

Burton-Jones, Andrew 11 August 2005 (has links)
Information systems are designed to support human and organizational purposes. To achieve their ends, information systems must be used. Although this may seem to be self-evident, there are many aspects of systems usage that are not so, and yet, in spite of this, there has been little intense conceptual scrutiny of this construct in past research. The objective of this thesis, therefore, is to develop new in-depth perspectives for studying system usage. Drawing on critical realist assumptions and studies of research diversity, I explain how epistemological factors enable while ontological factors constrain the diversity of meanings of system usage, and I build on this reasoning to advance a systematic approach for conceptualizing and measuring system usage in an appropriate way for a given research context. To demonstrate the approach and judge its usefulness, I carry out three empirical studies to test whether measures of system usage that are selected according to the proposed approach provide more explanatory power and lead to more coherent results in specific research contexts than other measures of system usage. Exploring the relationship between system usage and user task performance among 804 users of spreadsheet software, the experiments reveal support for the usefulness of the approach and demonstrate how it can enable researchers to conceptualize and measure system usage in an appropriate manner for a given research context. Together, the conceptual approach and empirical studies contribute by: (1) providing a systematic way to conceptualize and measure system usage for a given study context, (2) revealing rich new directions for research on the nature of system usage, its antecedents, and its consequences, and (3) suggesting a new approach for construct development and investigation in IS research.
5

Health Information Exchange Use in Primary Care

Apathy, Nathan Calvert 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The United States has invested over $40 billion in digitizing the health care system, yet the anticipated gains in improved care coordination, quality, and cost savings remain largely unrealized. This is due in part to limited interoperability and low rates of health information exchange (HIE) use, which can support care coordination and improve provider decision-making. Primary care providers are central to the US health care delivery system and frequently function as care coordinators, yet capability and HIE use gaps among these providers limit the potential of these digital systems to achieve their intended goals. I study HIE use in the context of primary care to examine 1) factors associated with provider HIE use, 2) the extent and nature of team-based HIE use, and 3) differences in HIE system use patterns across discrete groups of system users. First, I use a national sample of primary care providers to analyze market and practice factors related to HIE use for patient referrals. Overall, I find that only 43% of primary care provider referrals used HIE. Furthermore, I find substantial variation in HIE use rates across electronic health record (EHR) vendors. Second, I use HIE system log data to understand the breadth and depth of HIE use among teams, a care model underpinning primary care delivery reform efforts. I find that although use of HIE systems remains low, in primary care settings it overwhelmingly takes place in a manner consistent with team-based care workflows. Furthermore, team-based use does not differ in breadth from single provider HIE use, but illustrates less depth before and after visits. Third, I apply cluster analysis to 16 HIE use measures representing 7 use attributes, and identify 5 discrete user groups. I then compare two of these user groups and find user-level variation in volume and efficiency of use, both of which have implications for HIE system design and usability improvements. Ultimately, these findings help to inform how HIE use can be increased and improved in primary care, moving the US health care system closer to realizing the coordination, quality, and cost savings made possible by a digitized delivery system.
6

Towards a New GIS Maturity Model: An Organizational Usage Perspective

Alrwais, Omer Abdulaziz 01 January 2016 (has links)
The first condition required for an Information Technology (IT) system to produce value is that it be used by its designated target group of users. Despite the prevalence of “system use” in IS literature, it has been often limited to the individual level. The organizational perspective is rarely considered. This dissertation focuses on system usage in the GIS domain through an organizational lens. GIS is a technology with the potential to transform government by enhancing business processes and providing a platform to manage spatial and non-spatial data, which is expected to result in better decision-making. However, little is known about how this technology is actually implemented organization-wide and the environment surrounding its use. Current GIS maturity models have not examined this usage broadly or in depth. These models lack empirical validation and measurement tools to diagnose maturity are not readily available. Based on GIS, maturity models, and system usage literature, this dissertation presents a more comprehensive maturity model for evaluating local government usage of GIS along with a measurement tool. This work followed De Bruin et al., (2005) guidelines for developing maturity models. This new model was discussed with practitioners and academics, was pilot-tested, and then widely tested by Southern California local governments through an online questionnaire. Results show support for the validity of the proposed maturity model and demonstrate its utility. This dissertation revealed that system, task, user, organization and GIS department are viable dimensions of GIS usage from an organizational perspective. Results suggest that increasing actual GIS usage leads to an increase in GIS value. Results further show that the efficiency and effectiveness benefits of GIS are mostly realized; however, the societal benefits of GIS are small.
7

[en] OPTIMAL CONTRACTING OF TRANSMISSION SYSTEM USAGE AMOUNTS VIA FLEXIBLE STATIC EQUIVALENTS AND PROBABILISTIC LOAD FLOW. / [pt] CONTRATAÇÃO ÓTIMA DOS MONTANTES DE USO DO SISTEMA DE TRANSMISSÃO VIA EQUIVALENTES ESTÁTICOS FLEXÍVEIS E FLUXO DE POTÊNCIA PROBABILÍSTICO

NATASHA SOARES MONTEIRO DA SILVA 24 January 2019 (has links)
[pt] Na década de noventa, no Brasil, havia uma predominância de empresas verticalizadas no setor elétrico, pertencentes aos governos estaduais e federais, que no decorrer do processo de reestruturação e privatização sofreram uma desverticalização das suas atividades, em geração, transmissão, distribuição e comercialização. Após iniciada a privatização das companhias foi criada a Agência Nacional de Energia Elétrica (ANEEL),responsável por regular as atividades do setor elétrico brasileiro. Estas mudanças acarretaram em diferentes modelos de mercado caracterizados pelo acentuado uso dos sistemas de transmissão. Neste cenário, foi definido pela ANEEL que as concessionárias de distribuição devem pagar às transmissoras pela utilização de suas instalações o Encargo de Uso do Sistema de Transmissão (EUST). Para isso, é necessário informar o Montante de Uso do Sistema de Transmissão (MUST) para cada ponto de conexão e período tarifário por meio do Contrato de Uso do Sistema de Transmissão (CUST). Em caso de ultrapassagem dos valores firmados neste contrato acima de um percentual estipulado, a contratante terá que pagar uma penalidade. Esta dissertação tem por finalidade apresentar uma nova metodologia na determinação do valor ótimo do MUST, baseado em equivalentes estáticos flexíveis, fluxo de potência probabilístico e técnicas de otimização estocástica de modo a equilibrar o custo do transporte de energia e o custo da penalidade. Primeiro, utiliza-se uma técnica de redução de rede, flexível e precisa. Segundo, as incertezas provenientes das cargas, geração e topologia da rede são mapeadas nos pontos de conexão em análise. Terceiro, utiliza-se uma técnica simples de otimização estocástica para obter o MUST a ser contratado, pela distribuidora de energia elétrica, em cada barra de fronteira. Por último, a metodologia proposta é empregada no sistema acadêmico IEEE RTS com o objetivo de demonstrar a sua eficiência sendo os resultados obtidos amplamente discutidos. / [en] In Brazil, during the 1990s, there was a predominance of vertical companies in the electricity sector, belonging to the state and federal governments, which in the course of the restructuring and privatization process suffered a deverticalization of their activities into generation, transmission, distribution, and commercialization. After the beginning of this privatization process, the National Electric Energy Agency (ANEEL) was created, which is responsible for regulating the activities of the Brazilian electricity sector. These changes have led to different market models characterized by the strong use of the transmission systems. In this scenario, it was defined by ANEEL that the distribution concessionaires must pay the transmission companies for the use of their equipment. Thus, it is necessary to inform the Transmission System Usage Amount (MUST) for each connection point and tariff period by means of the Transmission System Use Agreement (CUST). In case of exceeding a specified percentage of the contracted amounts, the contractor will have to pay penalties. This dissertation aims to present a new methodology to determine the optimal value of MUST, based on flexible static equivalents, probabilistic power flow, and stochastic optimization techniques, in order to balance the energy transport and penalty costs. First, a flexible and accurate network reduction technique is used. Second, the uncertainties arising from the load, generation, and topology of the network are mapped at the connection points under analysis. Third, a simple stochastic optimization technique is used to obtain the MUST to be contracted by the electric power distributor at each border bus. Finally, the proposed methodology is used in the IEEE RTS academic system in order to demonstrate its efficiency, and the obtained results are widely discussed.
8

[pt] APLICAÇÕES DO MÉTODO DA ENTROPIA CRUZADA EM ESTIMAÇÃO DE RISCO E OTIMIZAÇÃO DE CONTRATO DE MONTANTE DE USO DO SISTEMA DE TRANSMISSÃO / [en] CROSS-ENTROPY METHOD APPLICATIONS TO RISK ESTIMATE AND OPTIMIZATION OF AMOUNT OF TRANSMISSION SYSTEM USAGE

23 November 2021 (has links)
[pt] As companhias regionais de distribuição não são autossuficientes em energia elétrica para atender seus clientes, e requerem importar a potência necessária do sistema interligado. No Brasil, elas realizam anualmente o processo de contratação do montante de uso do sistema de transmissão (MUST) para o horizonte dos próximos quatro anos. Essa operação é um exemplo real de tarefa que envolve decisões sob incerteza com elevado impacto na produtividade das empresas distribuidoras e do setor elétrico em geral. O trabalho se torna ainda mais complexo diante da crescente variabilidade associada à geração de energia renovável e à mudança do perfil do consumidor. O MUST é uma variável aleatória, e ser capaz de compreender sua variabilidade é crucial para melhor tomada de decisão. O fluxo de potência probabilístico é uma técnica que mapeia as incertezas das injeções nodais e configuração de rede nos equipamentos de transmissão e, consequentemente, nas potências importadas em cada ponto de conexão com o sistema interligado. Nesta tese, o objetivo principal é desenvolver metodologias baseadas no fluxo de potência probabilístico via simulação Monte Carlo, em conjunto com a técnica da entropia cruzada, para estimar os riscos envolvidos na contratação ótima do MUST. As metodologias permitem a implementação de software comercial para lidar com o algoritmo de fluxo de potência, o que é relevante para sistemas reais de grande porte. Apresenta-se, portanto, uma ferramenta computacional prática que serve aos engenheiros das distribuidoras de energia elétrica. Resultados com sistemas acadêmicos e reais mostram que as propostas cumprem os objetivos traçados, com benefícios na redução dos custos totais no processo de otimização de contratos e dos tempos computacionais envolvidos nas estimativas de risco. / [en] Local power distribution companies are not self-sufficient in electricity to serve their customers, and require importing additional energy supply from the interconnected bulk power systems. In Brazil, they annually carry out the contracting process for the amount of transmission system usage (ATSU) for the next four years. This process is a real example of a task that involves decisions under uncertainty with a high impact on the productivity of the distributions companies and on the electricity sector in general. The task becomes even more complex in face of the increasing variability associated with the generation of renewable energy and the changing profile of the consumer. The ATSU is a random variable, and being able to understand its variability is crucial for better decision making. Probabilistic power flow is a technique that maps the uncertainties of nodal injections and network configuration in the transmission equipment and, consequently, in the imported power at each connection point with the bulk power system. In this thesis, the main objective is to develop methodologies based on probabilistic power flow via Monte Carlo simulation, together with cross entropy techniques, to assess the risks involved in the optimal contracting of the ATSU. The proposed approaches allow the inclusion of commercial software to deal with the power flow algorithm, which is relevant for large practical systems. Thus, a realistic computational tool that serves the engineers of electric distribution companies is presented. Results with academic and real systems show that the proposals fulfill the objectives set, with the benefits of reducing the total costs in the optimization process of contracts and computational times involved in the risk assessments.
9

[pt] INCENTIVOS REGULATÓRIOS E ECONÔMICOS PARA USINAS HÍBRIDAS RENOVÁVEIS / [en] ON THE REGULATORY AND ECONOMIC INCENTIVES FOR RENEWABLE HYBRID POWER PLANTS IN BRAZIL

PEDRO GEORGE PRESCOTT FERRAZ 07 December 2023 (has links)
[pt] A complementaridade entre os perfis de geração renovável tem sido amplamente explorada na literatura. No entanto, as estruturas regulatórias eeconômicas para usinas híbridas de energia apresentam desafios e oportunidades interessantes para investidores, reguladores e planejadores. Focando nomercado de energia brasileiro, este artigo propõe um cálculo unificado e isonômico de Garantia Física (GF) para geradores renováveis não controláveis, quenos permite 1) generalizar o conceito de GF para unidades híbridas e 2) capturar as sinergias regulatórias e econômicas entre as fontes. Com base na GFnão discriminatória proposta para usinas híbridas de energia, a co-otimizaçãodas estratégias de contratação de energia no mercado de futuro e da rede, o Montante de Uso do Sistema de Transmissão (MUST), é estudada, e seus incentivos econômicos são demonstrados. A participação ótima de fontes renováveisque compõem a geração da usina híbrida também é considerada no modelo eanalisada em nossos estudos de caso. Com base em dados reais do mercadode energia brasileiro, quantificamos os benefícios das estruturas e modelos demercado propostos para uma unidade híbrida típica de eólico-solar. / [en] The complementarity between renewable generation profiles has been widely explored in literature. Notwithstanding, the regulatory and economic frameworks for hybrid power plants add interesting challenges and opportunities for investors, regulators, and planners. Focusing on the Brazilian power market, this paper proposes a unified and isonomic firm energy certificate (FEC) calculation for non-controllable renewable generators, which allows us to 1) generalize the FEC concept for hybrid units and 2) capture the regulatory and economic synergies between sources. Based on the non-discriminatory FEC proposed for hybrid power plants, the co-optimization of both forward-market and network-access contracting strategies is studied, and its economic incentives are demonstrated. The optimal share of renewable sources composing the hybrid power plant is also considered in the model and analyzed in our case studies. Based on real data from the Brazilian power market, we quantify the benefits of the proposed market structures and model for a typical wind–solar hybrid unit.
10

A model representing the factors that influence virtual learning system usage in higher education

Padayachee, I 06 1900 (has links)
In higher education institutions, virtual learning systems (VLSs) have been adopted, and are becoming increasingly popular among educators. However, despite this ubiquity of VLS use, there has not been widespread change in pedagogic practice to take advantage of the functionality afforded by VLSs. Knowledge of the actual usage of e-learning systems is limited in terms of what specific feature sets are deemed useful, and how this influences system usage. VLSs have a suite of tools with associated functions/features and properties, as well as non-functional system characteristics. In addition, these systems incorporate pedagogic features to cater for online teaching. Educators in higher education, who are the chief agents of e-learning, are confounded by system-related, pedagogic, organisational, user difference and demographic factors that influence VLS usage. Virtual learning system usage involves system feature usage extent and frequency, total system usage and usage clusters. The aim of this study is to develop a model representing the factors that influence usage of VLSs in higher education. The links between system usage and system-related factors, pedagogic factors, organisational factors, user-difference and demographic factors is researched. This research incorporated a literature study, a pilot study, interviews and surveys. A case study research strategy was combined with a mixed methods research design. The results of the qualitative analysis was triangulated with the findings of the quantitative analysis and compared to the findings of the literature study. The study was conducted at two residential higher education institutions (HEI), namely, University of KwaZulu-Natal and Durban University of Technology. The main contribution of this study is the Virtual Learning System Usage Model (VLSUM) representing the factors that influence VLS usage in residential higher education institutions. The proposed VLSUM is based on the empirical results of this study. VLSUM can be used by managers of educational technology departments and instructional designers to implement interventions to optimize usage. The constructs of VLSUM confirmed existing theories, replicated and synthesised theories from different fields, and extended existing models to produce a new model for understanding the factors that influence VLS usage in higher education. / Computing / D. LITT. et. Phil. (Information Systems)

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