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Design of Phase Measurement Systems for Phasing Identification of Distribution TransformersTsou, Yao-yang 08 July 2008 (has links)
Taipower Company has already completed the installation of the Outage Management System (OMS) automatic mapping and facility management system in all service districts. However, the service phases of distribution transformers (DT¡¦s) are difficult to be identified without applying the proper instruments because of under-ground systems with complicated connection of facility components. The phase information of transformers in the OMS database is often inconsistent with the actual service phase, leading to a decrease in the performance of distribution system analysis, planning, and operation of Taipower System.
The objective of this thesis is to present a new Phasor Measurement System (PMS) to identify the phases of DT¡¦s to support the update of OMS of Taipower Company. The attributes of DT¡¦s in OMS, including the locations and Utility Facility Identifications (UFID), are downloaded to a portable personal computer. The PMS will measure the voltage levels of the potential transformer in substations (S/S) and secondary side of field transformers for the calculation of phase angles with the synchronized mode. By integrating the GPRS communication module in the PMS, the time synchronization of two PMS units at the S/S and the DT can be obtained. The voltage phase angle at S/S can be retrieved by the PMS units as reference for phasor comparison to identify the phases of DT¡¦s.
The PMS developed in this study includes two units, which will be installed at S/S and field DT sites respectively. The voltage measurement and process module are used to measure voltage signals at the S/S and DT. The PMS at S/S will transmit the phase angle with time tag to the PMS at DT to identify the phases of DT¡¦s. The proposed PMS to be presented in this study will enhance the effectiveness of the PMS used by the Taipower distribution system. By integrating the interface program, the transformer phases information in OMS can be updated to support various distribution system application functions more effectively.
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The Application of Outage Management System to Distribution System Loss AnalysisChen, Yu-Wen 23 June 2005 (has links)
This thesis is to study the distribution system loss by applying the outage management system (OMS). To enhance the efficiency of loss analysis, the distribution system network has been obtained by retrieving the component information from OMS database. The topology process and node reduction have also been applied to identify the network configuration and to prepare the input data for load flow analysis. The load survey study is used to derive the typical load patterns of various customer classes. With the monthly energy consumption of customers served by each transformer, which has been retrieved from the customer information system (CIS), the hourly loading of each distribution transformer is then derived. By executing the three phase load flow analysis for different types of distribution feeders, the power loss of distribution feeders has been obtained, which will be used to evaluate the operation efficiency of whole distribution system.
To demonstrate the effectiveness of proposed methodology to solve distribution system loss, three practical distribution feeders in Taipei City District of Taipower are selected for computer simulation. With many transformers to serve voluminous low tension residential and commercial customers and high tension commercial and official customers in Taipei, the transformer core loss and high tension line loss contribute most of the distribution feeder loss. According to distribution feeder loss analysis, the transformer copper loss and low tension line loss are varied with the customer loading. With the distribution system loss model derived in this thesis, the distribution system loss can be estimated in a very efficient manner, which can provide utility an effective tool to analyze the power loss of whole distribution system and each individual feeder for assessment of system operation efficiency.
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Optimal Capacitor Planning of Distribution Feeders Using Immune AlgorithmWu, Jiun-De 05 July 2006 (has links)
Power System consists of generation, transmission and distribution systems to deliver the power service to customers. Distribution systems cover a very wide area with components such as main transformers, primary feeders, laterals, distribution transformers, low tension lines and meters. All these components contribute distribution line loss to deteriorate system operation efficiency. With the power system deregulation and Kyoto Protocol, it becomes an important issue for utility companies to achieve loss minimization by various strategies. The objective of this thesis is to derive both the optimal planning of capacitor placement and the operation strategy of switched capacitors by considering the loss reduction and investment cost of capacitors. A practical distribution feeder in Taipower has been selected for three-phase load flow analysis to solve power loss by considering the mutual-coupling effect and feeder daily load curve. The loading in each service zone is analyzed according to the feeder network configuration and power consumption of customers served. The immune algorithm is utilized to derive the optimal locations and capacity of capacitors to be installed along the feeder.
To demonstrate the effectiveness of the proposed capacitor planning, Feeder BW34, which served by Shang-Liao secondary substation of Feng-Shan District, is selected for computer simulation. The installation locations of both fixed and switched capacitors as well as the operation time of switched capacitors are determined according to the reactive power loading profiles of distribution feeders and distribution transformers. With the optimal capacitor planning proposed, the feeder power loss can be reduced effectively and cost benefit of capacitor investment can be enhanced too.
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Connectivity Identification of Distribution Transformers and Customers Served Using Power Line Carrier TechnologyChou, Hsing-chih 08 July 2008 (has links)
This thesis is to develop the power line carrier based
identifier for the determination of customers served by each
distribution transformer. The signal transmission characteristics
of the power line carrier (PLC) over low voltage distribution
lines and investigated. By executing the connectivity validation
with the identifier developed, the accuracy of outage
management system database can be enhanced for different
types of customers (commercial /office buildings, commercial/
buildings, residential buildings) Various application functions
such as contingency maintenance, transformer load
management and customer outage management can be
supported by outage management system (OMS) system more
effecting.
The mathematical models of 1£r2W, 1£r3W, 3£r3W and
3£r4W distribution have been developed by including the high
frequency equivalent circuits of transformers, low voltage lines
and customer loads in the computer simulation. The systems of
signal coupling circuit, data processing, man machine interface
have been designed with the embedded firmware for the PLC
identifier.
To demonstrate the effectiveness of the PLC identifier, a
field test has been performed in Tainan District of Taipower. It
is found that the customers served by each distribution
transformer can be determined correctly with the PLC identifier
developed.
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Elucidating the organic-OMS interface and its implications for heterogeneous catalystsWang, Qingqing 2011 May 1900 (has links)
Organic – ordered mesoporous silica (OMS) hybrid materials have attracted great interest due to their potential applications for gas separations, and heterogeneous catalysis. Amine-functionalized OMS materials are active in a variety of base-catalyzed reactions. The key to successfully achieving the desired reactivity is the ability to rationally tether the targeted organic functionality onto the OMS surface. Understanding the organic-inorganic interface is crucial for rational design of heterogeneous catalysts, because the local structure and molecule dynamics are paramount in determining the reactivity of the organic groups attached to the OMS surface. This dissertation focuses on three goals that will lead to a description of the organic-OMS interface and designing hybrid catalysts: 1) Determining the dynamics of organic groups attached to the OMS surface, 2) Catalytic testing to understand how the local structure and dynamics of the organic moiety influence the catalytic properties of organic-OMS catalysts, 3) Designing more active hybrid catalysts by introducing higher loadings of organic group using dendrimer structures.
Solid-state NMR is uniquely suited for quantifying dynamics in the milli- to nano-second time scale. Deuterium (2H) NMR is a powerful tool to obtain detailed information about the dynamics or organic molecules. In this study, several simple functional groups isotopically labeled with deuterium have been attached to MCM-41 and SBA-15. The spectra display different molecular motions for different organic moieties. The results have indicated that the interactions between the functional groups and silanol groups on the surface influence the mobility of the organic fragments. Also, the porosity of the solid supports effects dynamics via confinement.
The catalytic properties of simple amine groups attached to MCM-41, containing primary, secondary, and tertiary amines have been compared in the Nitroaldol (Henry) reaction. The effects of amine identity, structure, loading, presence of surface silanols, and the substrate topology on the catalytic properties have been investigated. The dramatic decrease of the activity of amine-functionalized MCM-41 by capping the residual silanol groups with hexamethyldisilazane was ascribed to the decrease of the interactions of hydrogen bonding between the amine functional groups and surface silanols. The result was consistent with the changes of the molecular motions shown by 2H NMR measurements.
Fabricating OMS hybrid materials with high densities of organic functional groups leads to challenges in realizing uniform, catalytically active sites. Our group has immobilized melamine-based dendrimers on the surfaces of amine-functionalized SBA-15 materials by iterative synthesis procedures. The current studies in this dissertation mainly describe the catalytic properties of these dendrimers on SBA-15 and MCM-41 in the Nitroaldol (Henry) reaction, the transesterification reaction of triglycerides and methanol to synthesize methyl esters, and the cross aldol reaction between acetone and 5-hydroxymethylfurfural. The results indicate that the OMS-dendron materials have potential as solid base catalysts for a range of reactions.
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Study on Fault Restoration Strategy of Distribution Feeders and Main TransformersChen, I-Tsung 07 July 2007 (has links)
The demand for electric load in recent years has been growing consistently in Taiwan. Besides supplying the load demand, the electricity service of distribution systems has to be reliable to meet the power quality of high tech industry. For a fault contingency in distribution systems, the fault location has to be identified and isolated by operating the boundary line switches. The electricity service for the un-faulted but outaged area has to be restored by transfering the loading to the neighboring feeders. The service reliability of distribution systems, a comprehensive distribution automation system DAS is implemented by integrating the computer master station, the communication system and the remote controlling equipments. The master station of DAS system to perform the function of fault detection, isolation and restoration (FDIR) can accelerate the process of service restoration for fault contingency.
To support the topology process of distribution system network, the outage management system (OMS), which has also been installed in all Taipower districts to store the attributes of distribution components, has been applied in this study. The operating mapping system is created to support distribution system operation by retrieving the static data from the OMS system and the dynamic data of line switch status from the real time database (RTDB). By this way, the distribution system network is updated by executing the network topology processor according to the operation of line switches.
In this thesis, a rule-based expert system is developed for fault restoration of distribution systems. To assure the proposed switch operation plan for fault restoration can comply with the distribution system operation regulation in Taipower, all of the feeders with open the switch to each feeder are formulated as a supporting group. The reserve capacity of each supporting feeders is used to compare the loading of unfaulted but outaged sections for downstream restoration. Based on the embeded rule base in the application program, the op line switch plan for fault restoration can therefore be derived for dispatchers engineers to restore the service in a short time period.
Besides the FDIR function, the application software can also be used to derive the optimal switching operation for loading balance of distribution feeders to enhance the operation efficiency of distribution systems.
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Construindo consensos e não-consensos internacionais em saúde : os medicamentos irregularesGomes, Cammilla Horta 06 March 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Centro de Estudos Avançados Multidisciplinares, Programa de Pós-Graduação em Desenvolvimento, Sociedade e Cooperação Internacional, 2015. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-04-26T18:43:51Z
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2015_CammillaHortaGomes.pdf: 1689004 bytes, checksum: b62c9bed3a00902744d0a4691c5f4ee5 (MD5) / A ocorrência de “medicamentos irregulares” no mercado é uma ameaça ao direito à saúde. O presente estudo objetiva compreender, a partir do referencial analítico do Sistema-Mundo de Wallerstein, os processos de formulação de consensos internacionais - especificamente nas negociações multilaterais na Organização Mundial da Saúde (OMS), na área de medicamentos irregulares - estabelecendo uma reflexão crítica quanto aos interesses que podem determinar seus resultados. O trabalho de investigação foi estruturado em uma pesquisa documental na base de dados da OMS e em diversas bases de dados de documentos acadêmicos / científicos. Os dados coletados são apresentados e analisados comparativamente, com foco na identificação de conceitos relacionados a “medicamentos irregulares” - categoria analítica criada especialmente para o trabalho de pesquisa. A pesquisa propicia uma melhor compreensão dos processos negociadores na OMS sobre medicamentos irregulares, no período de 1985 a 2014, e apresenta um diagnóstico quanto à abordagem do tema pela literatura científica. Identificam-se problemas, limites e desafios no processo de construção de consensos internacionais sobre a questão dos medicamentos irregulares, e os achados sugerem que há interesses diversos, fora do campo social (da saúde pública), que determinam seus resultados. / The existence of “non-regular drugs” in the market is a threat to the right to health. This study aims at understanding, from the analytical perspective of Wallerstein’s World-System, the processes of achieving international consensus - specifically related to multilateral negotiations within the World Health Organization (WHO), concerning non-regular drugs - elaborating a critical thinking regarding the interests that might determine their results. The investigation work was structured as a documental research in the WHO database and in several other databases of scientific and academic documents. The data collected is presented and comparatively analyzed, with a focus on the identification of definitions relating to “non-regular drugs” - an analytical category created especially for this research project. The research enables further understanding of the negotiating processes within WHO concerning non-regular drugs, from 1985 to 2014, and presents a diagnosis related to the subject’s approach by the academic literature. We identify problems, constraints and challenges in the course of international consensus-building about non-regular drugs, and the results suggest that there are other interests, outside the social arena (public health), that influence its outcomes.
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Estudo retrospectivo de tumores odontogênicos em dois centros de estudo no Brasil e três no MéxicoLawall, Melaine de Almeida 04 May 2009 (has links)
Os tumores odontogênicos compõem um grupo de lesões incomuns, porém interessantes, que se forma a partir dos tecidos que dão origem aos dentes. Esses tumores vêm sendo estudados há décadas por patologistas e cirurgiões que buscam entender seus mecanismos de formação e desenvolvimento, assim como desenvolver técnicas adequadas de tratamento. Inúmeras foram as tentativas realizadas até hoje para classificar esses tumores odontogênicos, sendo a última a nova Classificação de Tumores Odontogênicos da Organização Mundial da Saúde, publicada em 2005. Assim sendo, este trabalho teve por objetivo determinar a prevalência dos tumores odontogênicos diagnosticados nos Serviços de Anatomia Patológica das Faculdades de Odontologia de Bauru (USP) e de Araçatuba (UNESP) no Brasil, e das Faculdades de Odontologia da UNAM, da UAM-X e do Laboratório privado Peribact no México, compará-las e definir um perfil da ocorrência desses tumores nessas instituições e países seguindo essa nova classificação. Todos os casos diagnosticados como tumores e cistos odontogênicos passíveis de reanálise diagnóstica foram selecionados dos arquivos dessas instituições. Os dados demográficos e os aspectos clínicos de cada lesão foram obtidos a partir dos laudos e das fichas de requisição de exame anatomopatológico e as lâminas examinadas por um avaliador. Os resultados demonstraram que a inclusão do queratocisto no grupo de tumores provocou uma alteração significante na prevalência dessas lesões. O tumor odontogênico queratocístico foi a lesão mais prevalente, seguida pelo odontoma, ameloblastoma e mixoma no Brasil e no México. Quanto aos dados demográficos e localização, nossos achados corroboram com aqueles descritos na maior parte dos trabalhos realizados em todo o mundo, com diferenças pontuais em países como a China. Entretanto, a falta de maiores conhecimentos biomoleculares e genéticos dificulta a compreensão dessas diferenças. / Odontogenic tumors constitute a group of uncommon and particularly interesting lesions, arising from the odontogenic tissues. These tumors have been studied for decades by pathologists and surgeons seeking understand the mechanisms of formation and development, and trying to develop appropriate techniques of treatment. Many were the attempts made so far to classify these odontogenic tumors, the most recent being the new classification of odontogenic tumor of the World Health Organization, published in 2005. Therefore, this study aimed to determine the prevalence of odontogenic tumors diagnosed in five centers of diagnostic pathology: Laboratory of Oral Pathology, Faculty of Dentistry of Bauru USP; Laboratory of Oral Pathology, Faculty of Dentistry of Araçatuba UNESP, in Brazil; and Department of Oral Pathology, Faculty of Dentistry UNAM; Laboratory of Oral Pathology, Faculty of Dentistry of UAM-Xochimilco and Peribact Laboratory, a private laboratory of oral pathology, in Mexico; compare them and develop a profile of the occurrence of these tumors in these institutions and countries, following this new classification. All cases diagnosed as odontogenic cysts and tumors were selected for diagnostic review. The demographic and clinical features were obtained from the records when available. The cases were re-evaluated, and the diagnosis in each case was confirmed or modified when necessary. The results showed that the inclusion of keratocyst in the group of tumors caused a significant change in the prevalence of these lesions. The keratocyst odontogenic tumor was the most prevalent lesion, followed by odontoma, ameloblastoma and myxoma in Brazil and Mexico. Our findings corroborate with those reported arround the world, with occasional differences in countries, such as China. However, the lack of molecular and genetic knowledge precludes a better comprehension of these differences.
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Estudo retrospectivo de tumores odontogênicos em dois centros de estudo no Brasil e três no MéxicoMelaine de Almeida Lawall 04 May 2009 (has links)
Os tumores odontogênicos compõem um grupo de lesões incomuns, porém interessantes, que se forma a partir dos tecidos que dão origem aos dentes. Esses tumores vêm sendo estudados há décadas por patologistas e cirurgiões que buscam entender seus mecanismos de formação e desenvolvimento, assim como desenvolver técnicas adequadas de tratamento. Inúmeras foram as tentativas realizadas até hoje para classificar esses tumores odontogênicos, sendo a última a nova Classificação de Tumores Odontogênicos da Organização Mundial da Saúde, publicada em 2005. Assim sendo, este trabalho teve por objetivo determinar a prevalência dos tumores odontogênicos diagnosticados nos Serviços de Anatomia Patológica das Faculdades de Odontologia de Bauru (USP) e de Araçatuba (UNESP) no Brasil, e das Faculdades de Odontologia da UNAM, da UAM-X e do Laboratório privado Peribact no México, compará-las e definir um perfil da ocorrência desses tumores nessas instituições e países seguindo essa nova classificação. Todos os casos diagnosticados como tumores e cistos odontogênicos passíveis de reanálise diagnóstica foram selecionados dos arquivos dessas instituições. Os dados demográficos e os aspectos clínicos de cada lesão foram obtidos a partir dos laudos e das fichas de requisição de exame anatomopatológico e as lâminas examinadas por um avaliador. Os resultados demonstraram que a inclusão do queratocisto no grupo de tumores provocou uma alteração significante na prevalência dessas lesões. O tumor odontogênico queratocístico foi a lesão mais prevalente, seguida pelo odontoma, ameloblastoma e mixoma no Brasil e no México. Quanto aos dados demográficos e localização, nossos achados corroboram com aqueles descritos na maior parte dos trabalhos realizados em todo o mundo, com diferenças pontuais em países como a China. Entretanto, a falta de maiores conhecimentos biomoleculares e genéticos dificulta a compreensão dessas diferenças. / Odontogenic tumors constitute a group of uncommon and particularly interesting lesions, arising from the odontogenic tissues. These tumors have been studied for decades by pathologists and surgeons seeking understand the mechanisms of formation and development, and trying to develop appropriate techniques of treatment. Many were the attempts made so far to classify these odontogenic tumors, the most recent being the new classification of odontogenic tumor of the World Health Organization, published in 2005. Therefore, this study aimed to determine the prevalence of odontogenic tumors diagnosed in five centers of diagnostic pathology: Laboratory of Oral Pathology, Faculty of Dentistry of Bauru USP; Laboratory of Oral Pathology, Faculty of Dentistry of Araçatuba UNESP, in Brazil; and Department of Oral Pathology, Faculty of Dentistry UNAM; Laboratory of Oral Pathology, Faculty of Dentistry of UAM-Xochimilco and Peribact Laboratory, a private laboratory of oral pathology, in Mexico; compare them and develop a profile of the occurrence of these tumors in these institutions and countries, following this new classification. All cases diagnosed as odontogenic cysts and tumors were selected for diagnostic review. The demographic and clinical features were obtained from the records when available. The cases were re-evaluated, and the diagnosis in each case was confirmed or modified when necessary. The results showed that the inclusion of keratocyst in the group of tumors caused a significant change in the prevalence of these lesions. The keratocyst odontogenic tumor was the most prevalent lesion, followed by odontoma, ameloblastoma and myxoma in Brazil and Mexico. Our findings corroborate with those reported arround the world, with occasional differences in countries, such as China. However, the lack of molecular and genetic knowledge precludes a better comprehension of these differences.
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Three Phase Balancing of Distribution Systems Using Heuristic RulesHuang, Chih-Wei 09 July 2007 (has links)
In this paper, the heuristic rules are proposed to derive the rephasing strategy of laterals and distribution transformers to improve the three phase unbalance of distribution systems. The distribution feeder network has been obtained by retrieving the attribute data of distribution components from the database of outage management system (OMS) in Taipower. The topology process and node reduction have also been executed to identify the network configuration and to prepare the input data for load flow analysis. With the monthly energy consumption of customers served by each transformer, which has been retrieved from the Customer Information System (CIS), the hourly loading of each distribution transformer can be derived. By performing the three phase load flow analysis, the three phase currents and neutral current of each primary trunk line section and each lateral can be calculated. The heuristic rule is employed to determine the phase adjustment strategy laterals and distribution transformers for rephasing to achieve three phase balancing.
In order to demonstrate the effectiveness of the proposed methodology for three phase balancing, two practical distribution feeders in Taipower Fengshan District are selected for simulation. After rephasing the distribution transformers and laterals proposed by this paper, the three phase currents and netural of the test feeders have been collected. By companing to the neutral current before rephasing, it is found that the neutral current of test feeders have been reduced significantly and there phase balancing has been obtained by executing the proposed strategy derived using the heuristic rule.
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