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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.
41

Gender Specific Features of Language : Their Representation in a Popular TV Show

Boström Eriksson, Linda January 2008 (has links)
<p>The aim of this study was to find out how features that have been found to be typical of women’s language, such as hedges, tag questions and a high level of talkativeness etc., are represented in a popular TV series. Five cross-sex conversations from one episode of the sitcom <em>The New Adventures of Old Christine </em>were analyzed, and the results show that many of the features of interest, as for instance tag questions, minimal responses and indirect style, are unexpectedly used more frequently by men in this small investigation. In fact, the only feature that was used more frequently by the female main character was hedges. Several factors affect the results of the study, as for instance the fact that the conversations are fictional. The special characteristics of the speakers also affect the results, as well as the tone and the topic of the chosen conversations. Many of the features of interest were used to a very small extent, which is probably a result of the fact that the language in a sitcom is to be entertaining and rather quick, which leaves little or no room for the features studied.</p>
42

Fjärrfrånskiljares inverkan på kundavbrottstiden i Vattenfall Eldistributions lokalnät

Larsson, Hans January 2009 (has links)
<p>I samband med de ökade kraven på ett vädersäkrat nät har funderingar kring att placera ut fler frånskiljare/brytare i luftledningsnätet för att reducera medelavbrottstiden för anslutna kunder (SAIDI) kommit fram. I Finland använder man till stor del fjärrmanövrerade apparater för att reducera SAIDI. Rapportens inledande avsnitt innefattar en förstudie om ursprunget till avbrottstid och SAIDI-statistik i Vattenfall Eldistributions nät. En jämförelse med Eldistributions nät och klimatet i Finland utförs och av detta fås olika förutsättningar för nätet i de olika länderna. Som en generell slutsats av väderjämförelsen mellan Sverige och Finland fastställs att Eldistribution i Sverige har sämre förutsättningar vädermässigt när det gäller luftledningsnät. Resultaten från beräkningarna på sex exempelnät visar att den maximala reduceringen av SAIDI uppgår till 36 % och den minimala med 17 % i exempelnäten. Om alla nät skulle gå att bygga om enligt liknande principer skulle det innebära en reducering av Eldistributions mellanspännings-SAIDI med cirka 12 % ifall de 200 sämsta linjerna ur SAIDI-synpunkt kompletterades med fjärrfrånskiljare i motsvarande grad som exempelnäten. Jämförelser av investeringskostnader mellan fjärrfrånskiljaralternativ och kablifieringsalternativ visar att det är mer kostnadseffektivt att bygga om med fjärrfrånskiljare och därför är detta lämpligt om önskan är att så billigt som möjligt reducera SAIDI. Som en allmän rekommendation bör reservmatningar i nätet vara fjärrmanövrerade och dessutom bör linjer ha minst en fjärrfrånskiljare utlokaliserad. Då delas linjen upp i fler fjärrsektioneringsområden vilket förbättrar kundavbrottstiden för linjen. Ifall en linje inte har reservmatningmöjligheter bör det utredas ifall det är möjligt att med acceptabelt stora resurser bygga ihop nätet med ett annat nät för att möjliggöra en reservmatningsväg. Om det finns fler platser på linjen som är lämpliga för komplettering med fjärrfrånskiljare bör dessa utnyttjas för att så prisvärt som möjligt få ner SAIDI på den aktuella linjen. Ett allmänt råd angående antalet fjärrfrånskiljare per linje är svårt att ge men generellt sett är den första fjärrfrånskiljaren mycket mer kostnadseffektiv än de efterföljande. Stolpbrytare (reclosers) bör placeras ut där goda förutsättningar finns för att det skall bli lönsamt. Exempel på sådana platser kan vara vid övergång från kabel till luftledningsnät och innan en sträcka där fel ofta inträffar.</p> / <p>An alternative approach in Vattenfall Eldistribution’s network has evolved from the increased demands on reducing network downtime. Eldistribution are using remote controlled disconnectors / reclosers in Finland to reduce the system average interruption duration index (SAIDI). The initial section of the report includes a study on the source of downtime and SAIDI-statistics in Eldistribution’s network. A comparison with network and the climate in Finland is carried out which indicate different conditions in the two countries. The weather comparison shows that it’s more difficult to use non-insulated overhead-lines in Sweden because of the climate conditions. The result shows a maximum reduction of SAIDI by 36% and a minimum of 17% based on calculations on six example-lines. If all the lines would be possible to build under similar principles it would result in a reduction of Eldistributions SAIDI by approximately 12 % if the 200 worst lines was supplemented with remote controlled disconnectors with a corresponding amount of reduced SAIDI-minutes. Comparisons with cable alternatives show that it’s more cost-effective to invest in remoted controlled disconnectors if the target is a quick and cheap reduction of SAIDI. As a general recommendation the backup powering of a network should be remote controlled and the lines should have at least one outsourced remote controlled disconnector. This will split the line in multiple remote controlled areas, which will reduce disruption time for customers connected to the line. If a line doesn’t have any backup powering it should be investigated whether it’s possible to connect the line to another line to ensure backup-feeding if this is possible to do at acceptable costs. If there are more locations on the line suitable for supplementation of remote controlled disconnectors, those places should be used to get as much reduced SAIDI as possible at a cost-effective level. It's difficult to give a general advice concerning the number of remote controlled disconnectors but the first disconnector is generally more cost-effective than the subsequent ones. Reclosers should be deployed at appropriate locations to be equally costefficient as remoted controlled disconnectors. Examples of such places can be when switching from cable to non-insulated line and before a section where errors often occur.</p>
43

Gender Specific Features of Language : Their Representation in a Popular TV Show

Boström Eriksson, Linda January 2008 (has links)
The aim of this study was to find out how features that have been found to be typical of women’s language, such as hedges, tag questions and a high level of talkativeness etc., are represented in a popular TV series. Five cross-sex conversations from one episode of the sitcom The New Adventures of Old Christine were analyzed, and the results show that many of the features of interest, as for instance tag questions, minimal responses and indirect style, are unexpectedly used more frequently by men in this small investigation. In fact, the only feature that was used more frequently by the female main character was hedges. Several factors affect the results of the study, as for instance the fact that the conversations are fictional. The special characteristics of the speakers also affect the results, as well as the tone and the topic of the chosen conversations. Many of the features of interest were used to a very small extent, which is probably a result of the fact that the language in a sitcom is to be entertaining and rather quick, which leaves little or no room for the features studied.
44

Fjärrfrånskiljares inverkan på kundavbrottstiden i Vattenfall Eldistributions lokalnät

Larsson, Hans January 2009 (has links)
I samband med de ökade kraven på ett vädersäkrat nät har funderingar kring att placera ut fler frånskiljare/brytare i luftledningsnätet för att reducera medelavbrottstiden för anslutna kunder (SAIDI) kommit fram. I Finland använder man till stor del fjärrmanövrerade apparater för att reducera SAIDI. Rapportens inledande avsnitt innefattar en förstudie om ursprunget till avbrottstid och SAIDI-statistik i Vattenfall Eldistributions nät. En jämförelse med Eldistributions nät och klimatet i Finland utförs och av detta fås olika förutsättningar för nätet i de olika länderna. Som en generell slutsats av väderjämförelsen mellan Sverige och Finland fastställs att Eldistribution i Sverige har sämre förutsättningar vädermässigt när det gäller luftledningsnät. Resultaten från beräkningarna på sex exempelnät visar att den maximala reduceringen av SAIDI uppgår till 36 % och den minimala med 17 % i exempelnäten. Om alla nät skulle gå att bygga om enligt liknande principer skulle det innebära en reducering av Eldistributions mellanspännings-SAIDI med cirka 12 % ifall de 200 sämsta linjerna ur SAIDI-synpunkt kompletterades med fjärrfrånskiljare i motsvarande grad som exempelnäten. Jämförelser av investeringskostnader mellan fjärrfrånskiljaralternativ och kablifieringsalternativ visar att det är mer kostnadseffektivt att bygga om med fjärrfrånskiljare och därför är detta lämpligt om önskan är att så billigt som möjligt reducera SAIDI. Som en allmän rekommendation bör reservmatningar i nätet vara fjärrmanövrerade och dessutom bör linjer ha minst en fjärrfrånskiljare utlokaliserad. Då delas linjen upp i fler fjärrsektioneringsområden vilket förbättrar kundavbrottstiden för linjen. Ifall en linje inte har reservmatningmöjligheter bör det utredas ifall det är möjligt att med acceptabelt stora resurser bygga ihop nätet med ett annat nät för att möjliggöra en reservmatningsväg. Om det finns fler platser på linjen som är lämpliga för komplettering med fjärrfrånskiljare bör dessa utnyttjas för att så prisvärt som möjligt få ner SAIDI på den aktuella linjen. Ett allmänt råd angående antalet fjärrfrånskiljare per linje är svårt att ge men generellt sett är den första fjärrfrånskiljaren mycket mer kostnadseffektiv än de efterföljande. Stolpbrytare (reclosers) bör placeras ut där goda förutsättningar finns för att det skall bli lönsamt. Exempel på sådana platser kan vara vid övergång från kabel till luftledningsnät och innan en sträcka där fel ofta inträffar. / An alternative approach in Vattenfall Eldistribution’s network has evolved from the increased demands on reducing network downtime. Eldistribution are using remote controlled disconnectors / reclosers in Finland to reduce the system average interruption duration index (SAIDI). The initial section of the report includes a study on the source of downtime and SAIDI-statistics in Eldistribution’s network. A comparison with network and the climate in Finland is carried out which indicate different conditions in the two countries. The weather comparison shows that it’s more difficult to use non-insulated overhead-lines in Sweden because of the climate conditions. The result shows a maximum reduction of SAIDI by 36% and a minimum of 17% based on calculations on six example-lines. If all the lines would be possible to build under similar principles it would result in a reduction of Eldistributions SAIDI by approximately 12 % if the 200 worst lines was supplemented with remote controlled disconnectors with a corresponding amount of reduced SAIDI-minutes. Comparisons with cable alternatives show that it’s more cost-effective to invest in remoted controlled disconnectors if the target is a quick and cheap reduction of SAIDI. As a general recommendation the backup powering of a network should be remote controlled and the lines should have at least one outsourced remote controlled disconnector. This will split the line in multiple remote controlled areas, which will reduce disruption time for customers connected to the line. If a line doesn’t have any backup powering it should be investigated whether it’s possible to connect the line to another line to ensure backup-feeding if this is possible to do at acceptable costs. If there are more locations on the line suitable for supplementation of remote controlled disconnectors, those places should be used to get as much reduced SAIDI as possible at a cost-effective level. It's difficult to give a general advice concerning the number of remote controlled disconnectors but the first disconnector is generally more cost-effective than the subsequent ones. Reclosers should be deployed at appropriate locations to be equally costefficient as remoted controlled disconnectors. Examples of such places can be when switching from cable to non-insulated line and before a section where errors often occur.
45

A Linguistic Hybrid? : a study of male linguistic features in female conversation

Lucchesi, Emilia January 2011 (has links)
This study investigates four women’s use of typically male linguistic features in casual same-sex conversation. The aim of the study is to see whether and how this group of women use the linguistic features; swearing, interrupting, disagreeing and ignoring, questions and monologues (‘playing the expert’) which are all more common in male conversation and often part of a competitive communication style. I will also attempt to answer if these women’s linguistic behavior is typically female or male. The four women were tape recorded during a planned conversation in a casual setting and the recording was transcribed. The transcription was analyzed by using definitions of the linguistic features above made by, for example, Jennifer Coates (2004). The results show that these four women were neither typically female nor male, but a mix of the two; a hybrid.
46

Uma contribuição para a parametrização da proteção em sistemas de distribuição considerando custo de interrupções

Mattos, Marcel Souza January 2016 (has links)
A continuidade no fornecimento de energia elétrica a clientes é um objetivo constante das distribuidoras de energia, as quais estão constantemente buscando desenvolver soluções tecnológicas a fim de melhorar o desempenho das redes de distribuição. Com o crescimento das cargas eletrônicas e o expressivo aumento dos dispositivos automáticos nas redes, surge uma nova forma de analisar a rede de distribuição sob o aspecto da filosofia da proteção, considerando interrupções sustentadas e momentâneas, sob dois aspectos distintos, o primeiro considera o custo da energia não fornecida sob o período de contingência, enquanto que o segundo refere-se ao impacto do custo social para diferentes classes de clientes, durante o período das interrupções. Desta forma este trabalho propõe o desenvolvimento de uma estratégia de minimização de custos dessas interrupções considerando as características das cargas, bem como o tempo necessário para reinicialização da carga. Para este fim, é aplicado um modelo de programação não-linear, que emprega variáveis binárias para definir a habilitação ou não de curvas rápidas nos religadores e uma abordagem de otimização clássica. Os algoritmos foram desenvolvidos no software Matlab e posteriormente convertido para linguagem GAMS (Generic Algebraic Modeling System). A metodologia foi testada e validada em um alimentador de distribuição real urbano, localizado na região metropolitana de Porto Alegre (RS, Brasil). / Uninterrupted power delivery is a permanent goal of power utilities. One way of attaining this objective is constantly investing in technological solutions to improve the performance of distribution networks. With increasing loads, mainly electronic ones, as well as growing insertion of automatic reclosers, the protection philosophy of distribution systems has to be rethought taking into account temporary and permanent interruptions. In this work, we propose a strategy to minimize the cost of interruptions taking into account the load characteristics and the time required to restart the load. This is achieved by deriving a mixed integer nonlinear programming model. The proposed model uses binary variables to define if the instantaneous characteristic of the recloser should be enabled and a classical explicit mathematical optimization approach. The algorithms were developed with Matlab software and the conversion was made to a General Algebraic Modeling System (GAMS). The applicability of the proposed methodology is tested in an actual feeder from Porto Alegre.
47

Uma contribuição para a parametrização da proteção em sistemas de distribuição considerando custo de interrupções

Mattos, Marcel Souza January 2016 (has links)
A continuidade no fornecimento de energia elétrica a clientes é um objetivo constante das distribuidoras de energia, as quais estão constantemente buscando desenvolver soluções tecnológicas a fim de melhorar o desempenho das redes de distribuição. Com o crescimento das cargas eletrônicas e o expressivo aumento dos dispositivos automáticos nas redes, surge uma nova forma de analisar a rede de distribuição sob o aspecto da filosofia da proteção, considerando interrupções sustentadas e momentâneas, sob dois aspectos distintos, o primeiro considera o custo da energia não fornecida sob o período de contingência, enquanto que o segundo refere-se ao impacto do custo social para diferentes classes de clientes, durante o período das interrupções. Desta forma este trabalho propõe o desenvolvimento de uma estratégia de minimização de custos dessas interrupções considerando as características das cargas, bem como o tempo necessário para reinicialização da carga. Para este fim, é aplicado um modelo de programação não-linear, que emprega variáveis binárias para definir a habilitação ou não de curvas rápidas nos religadores e uma abordagem de otimização clássica. Os algoritmos foram desenvolvidos no software Matlab e posteriormente convertido para linguagem GAMS (Generic Algebraic Modeling System). A metodologia foi testada e validada em um alimentador de distribuição real urbano, localizado na região metropolitana de Porto Alegre (RS, Brasil). / Uninterrupted power delivery is a permanent goal of power utilities. One way of attaining this objective is constantly investing in technological solutions to improve the performance of distribution networks. With increasing loads, mainly electronic ones, as well as growing insertion of automatic reclosers, the protection philosophy of distribution systems has to be rethought taking into account temporary and permanent interruptions. In this work, we propose a strategy to minimize the cost of interruptions taking into account the load characteristics and the time required to restart the load. This is achieved by deriving a mixed integer nonlinear programming model. The proposed model uses binary variables to define if the instantaneous characteristic of the recloser should be enabled and a classical explicit mathematical optimization approach. The algorithms were developed with Matlab software and the conversion was made to a General Algebraic Modeling System (GAMS). The applicability of the proposed methodology is tested in an actual feeder from Porto Alegre.
48

Avaliação de custos decorrentes de descargas atmosféricas em sistemas de distribuição de energia / Evaluation of the costs arising from atmospheric discharges in power distribution systems.

Alberto Akio Shiga 16 March 2007 (has links)
As descargas atmosféricas sempre foram tratadas como acontecimentos fortuitos e de força maior, inerentes à vontade do homem. Contudo, mudanças significativas a esse respeito ocorreram recentemente na legislação brasileira, no Código Civil e na norma ABNT NBR 5410: 2004 (Instalações Elétricas de Baixa Tensão). Além disso, em 29 de abril de 2004 foi publicada a Resolução Normativa nº 61 da ANEEL, que estabelece as disposições relativas ao ressarcimento de danos, em equipamentos elétricos instalados em unidades consumidoras, causados por perturbações no sistema elétrico. De acordo com essa nova visão, as descargas atmosféricas devem ser tratadas como fenômenos que podem ter as suas conseqüências previstas, evitadas ou ao menos minimizadas, fazendo com que os custos associados não sejam considerados simplesmente como prejuízos, mas sim passíveis de ressarcimento junto à concessionária. Tais fatores, aliados à inexistência de uma metodologia comum para análise dos prejuízos causados por esse fenômeno, motivaram a realização deste trabalho, que teve por objetivo avaliar os custos decorrentes de descargas atmosféricas em sistemas de distribuição de energia. Além de aspectos técnicos e jurídicos, são discutidos os custos referentes à energia não fornecida, danos em equipamentos, mão-de-obra e ressarcimento de pedidos de indenização por danos (PIDs). Discute-se ainda, embora de forma superficial, a importância de contabilização do custo da imagem da empresa junto aos consumidores. Finalmente, apresenta-se uma metodologia para determinação de tais custos, a qual é aplicada a casos reais, com comparação e análise dos resultados obtidos em diferentes situações. / Lightning discharges have always been treated as Acts of God and force majure events, inherent to man?s will. However, significant changes to this regard have recently occurred in the Brazilian Law, in the Civil Code and on the Brazilian Standard ABNT NBR 5410: 2004 (Low Voltage Electric Installations). In addition, on April 29th, 2004, ANEEL Normative Resolution No. 61 was published, which establishes the provisions regarding reimbursement of damages in electrical equipment installed in consumer units, caused by disturbances in the electrical system. According to this new version, the lightning discharges must be treated as phenomena which may have their consequences foreseen, avoided or at least minimized, causing the associated costs to be considered not only as losses, but also entitled to reimbursement with the operator. Such factors, allied to the non-existence of a common methodology for the review of the losses caused by such phenomenon, motivated the development of this work, which aimed at assessing the lightning-related costs in power distribution systems. In addition to the technical and legal aspects, the costs regarding non-supplied power, equipment damage, labor and indemnity claims (PIDs), are also discussed. Although superficially, the importance of taking into account the cost of the company?s image with the consumers is also discussed. Finally, a methodology for the determination of such costs is presented and applied to actual cases, with comparison and analysis of the results obtained in different situations.
49

Value of Fast Switching Devices to Electric Distribution Networks : An Approach to Reduce Voltage Sags and Interruptions in Distribution Networks

Kasala, Sinduri January 2014 (has links)
Power Quality (PQ) has gained a lot of importance in the last decade. Several solutions to power quality problems have been proposed and developed. With the advent of solid state technology and power electronics in the power system protection devices, faster switching is achievable. In order to control and minimize the power quality problems which occur in extremely short times of less than 100ms, the need arises for a selection of devices that can switch faster than today. Also, the economic losses that occur in the network due to the power quality problems increase the incentive to transform the existing devices into faster and e fficient devices. This transformation can be seen as valuable from both a technical and economical point of view to the distribution networks today where a large number of customers are connected. However, in order to interpret the value these fast switching devices render to the distribution network a prior study is required. This thesis presents a picture of the devices that can be suitable for fast switching in today’s distribution network, and how to determine their value to the distribution network. Further it summarizes the research work related to this field. The description of the devices and technical aspects is presented first. A literature review of proposed devices is given. The technical aspects of power quality and its problems is described. An approach to estimate the value of the fast switching devices is detailed from different literature. The study shows that fast switching devices can be worthy to invest in when seen from a distribution network’s perspective provided that different technical aspects are taken into account.
50

Properties and Impact of Vicinity in Mobile Opportunistic Networks / Propriétés et impact du voisinage dans les réseaux mobiles opportunistes

Phe-Neau, Tiphaine 23 January 2014 (has links)
Les réseaux opportunistes (DTN) permettent d'utiliser de nouveaux vecteurs de transmissions. Avant de pouvoir profiter de toutes les capacités des DTN, nous devons nous pencher sur la compréhension de ce nouveau paradigme. De nombreuses propriétés des réseaux DTN sont maintenant reconnues, cependant les relations entre un noeud du réseau et son voisinage proche ne semblent pas encore avoir été passée au crible. Souvent, la présence de noeuds voisins proches mais pas directement lié par le contact est ignorée. Dans cette thèse, nous montrons à quel point considérer les noeuds à proximité nous aide à améliorer les performances DTNs.En identifiant le paradoxe binaire dans les DTN, nous montrons que les caractérisations actuelles ne sont pas suffisantes pour bénéficier de toutes les possibilités de transmission dans les DTN. Nous proposons une définition formelle du voisinage pour les DTNs avec le ``k-vicinity''. Nous étudions les caractérisations temporelles du k-vicinity avec différentes données. Ensuite, nous nous concentrons sur l'étude de l'organisation interne du k-vicinity. Nous avons crée le Vicinity Motion qui permet d'obtenir un modèle markovien à partir de n'importe quelle trace de contact. Nous en extrayions trois mouvements principaux: la naissance, la mort et les mouvements séquentiels. Grâce aux valeurs du Vicinity Motion, nous avons pu créer un générateur synthétique de mouvements de proximité nommé TiGeR. Enfin, nous posons la question de la prévisibilité des distances entre deux noeuds du k-vicinity. En utilisant le savoir emmagasiné dans le Vicinity Motion, nous mettons au point une heuristique permettant de prédire les futures distances entre deux noeuds. / The networking paradigm uses new information vectors consisting of human carried devices is known as disruption-tolerant networks (DTN) or opportunistic networks. We identify the binary assertion issue in DTN. We notice how most DTNs mainly analyze nodes that are in contact. So all nodes that are not in contact are in intercontact. Nevertheless, when two nodes are not in contact, this does not mean that they are topologically far away from one another. We propose a formal definition of vicinities in DTNs and study the new resulting contact/intercontact temporal characterization. Then, we examine the internal organization of vicinities using the Vicinity Motion framework. We highlight movement types such as birth, death, and sequential moves. We analyze a number of their characteristics and extract vicinity usage directions for mobile networks. Based on the vicinity motion outputs and extracted directions, we build the TiGeR that simulates how pairs of nodes interact within their vicinities. Finally, we inquire about the possibilities of vicinity movement prediction in opportunistic networks. We expose a Vicinity Motion-based heuristic for pairwise shortest distance forecasting. We use two Vicinity Motion variants called AVM and SVM to collect vicinity information. We find that both heuristics perform quite well with performances up to 99% for SVM and around 40% for AVM.

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