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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.
1041

Ultracapacitor/Battery Hybrid Energy Storage Systems for Electric Vehicles

Moshirvaziri, Mazhar 22 November 2012 (has links)
This thesis deals with the design of Hybrid Energy Storage System (HESS) for Light Electric Vehicles (LEV) and EVs. More specifically, a tri-mode high-efficiency non-isolated half-bridge converter is developed for the LEV based HESS applications. A 2 kW, 100 V interleaved two-phase converter prototype was implemented. The peak efficiency of 97.5% and a minimum efficiency of 88% over the full load range are achieved. Furthermore, a power-mix optimizer utilizing the real-time Global Positioning System (GPS) data for the EV based HESS is proposed. For a specific design, it is shown that at the cost of less than 1.5% of the overall energy savings, the proposed scheme reduces the peak battery charge and discharge rates by 76% and 47%, respectively. A 30 kW bi-directional dc-dc converter is also designed and implemented for future deployment of the designed HESS into a prototype EV, known as A2B.
1042

Conception et évaluation d'un système transparent de capture de mouvements des mains pour l'interaction 3D temps réel en environnements virtuels

Hernoux, Franck 07 December 2011 (has links) (PDF)
Le but de cette thèse est de proposer et d'évaluer un système transparent de capture de mouvements des mains en temps réel pour permettre la réalisation d'interactions 3D en environnement virtuel (E.V.). Les outils tels que le clavier et la souris ne suffisent plus lorsque l'on travaille dans des E.V. 3D et les systèmes de capture de mouvements actuels ont l'inconvénient du coût et du port de matériel. Les systèmes basés sur des caméras et le traitement d'images comblent en partie ces lacunes, mais ne permettent pas encore une capture de mouvements 3D précise, efficace et temps réel. Notre système propose une solution à ce problème grâce à une caméra 3D. Nous avons implémenté des modalités qui permettent une interaction plus naturelle avec les objets et l'E.V. L'objectif de notre système est d'obtenir des performances au moins égales à celles d'outils couramment utilisés en réalité virtuelle tout en offrant une meilleure acceptabilité globale, mesurée sous l'angle de l'utilité, de l'utilisabilité et du sentiment d'immersion. Pour répondre à cet objectif, nous avons mené 3 études expérimentales impliquant plus de 100 participants. L'étude 1 a comparé, pour une tâche de sélection, la première version de notre système (basé sur une Camera 3D MESA SwissRanger) à une souris classique. L'expérimentation 2 est axée sur l'étude de la réalisation de tâches de manipulation d'objets (positionnement, orientation, redimensionnement) et de navigation en E.V. Pour cette étude, nous avons comparé la version améliorée de notre système (basée sur la Microsoft Kinect) à des gants de données associés à des capteurs magnétiques. La 3ème étude, complémentaire, porte sur l'évaluation de nouvelles modalités d'interaction, implémentées d'après les commentaires recueillis auprès des participants de la seconde étude.
1043

Space use pattern, dispersal and social organisation of the raccoon dog (Nyctereutes procyonoides), an invasive, alien canid in Central Europe / Raumnutzung, Ausbreitung und Sozialsystem des Marderhundes (Nyctereutes procyonoides), eines invasiven, allochthonen Kaniden in Zentraleuropa

Drygala, Frank 14 December 2009 (has links) (PDF)
Abstract Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young racoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radio-collared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.
1044

Social ångeststörning (SAD) och beteendeinhibering som barn – en psykometrisk och jämförande studie

Håkansson, Anders January 2014 (has links)
Social ångeststörning (SAD) är ett ångestsyndrom som orsakar stor funktionsnedsättning och försämrad livskvalitet. I föreliggande studie presenteras förklaringsmodeller till SAD med fokus på temperamentsforskning och reinforcement sensitivity theory (RST). Syftet var att genom explorativ faktoranalys identifiera latenta variabler i frågeformuläret ”Hur man var som barn” (HMVSB), som administrerats i en klinisk population (n= 100) och i en kontrollgrupp (n= 246). Faktoranalysen extraherade två faktorer som döptes till beteendeinhibering (BI) respektive beteendeaktivering (BA). Ett andra syfte var att jämföra den kliniska populationen med kontrollgruppen avseende de extraherade faktorerna. Resultaten visade att HMVSB uppvisade god intern konsistens och tillfredsställande instrumentell reliabilitet. Vissa signifikanta korrelationer mellan HMVSB och jämförda skattningsformulär vid SAD erhölls. Gruppjämförelserna visade att den kliniska gruppen var signifikant mer beteendeinhiberad och mer beteendeaktiverad som barn. En subgrupp med generaliserad SAD var både signifikant mer beteendeaktiverad och beteendeinhiberad som barn. Subgruppen med specifik SAD skilde sig ej signifikant från kontrollgruppen. Studien manar till att beakta temperamentala faktorer vid SAD där kombinationen hög BI och hög BA skulle kunna korrelera med allvarligare klinisk bild.
1045

On Weak Limits and Unimodular Measures

Artemenko, Igor 14 January 2014 (has links)
In this thesis, the main objects of study are probability measures on the isomorphism classes of countable, connected rooted graphs. An important class of such measures is formed by unimodular measures, which satisfy a certain equation, sometimes referred to as the intrinsic mass transport principle. The so-called law of a finite graph is an example of a unimodular measure. We say that a measure is sustained by a countable graph if the set of rooted connected components of the graph has full measure. We demonstrate several new results involving sustained unimodular measures, and provide thorough arguments for known ones. In particular, we give a criterion for unimodularity on connected graphs, deduce that connected graphs sustain at most one unimodular measure, and prove that unimodular measures sustained by disconnected graphs are convex combinations. Furthermore, we discuss weak limits of laws of finite graphs, and construct counterexamples to seemingly reasonable conjectures.
1046

Space use pattern, dispersal and social organisation of the raccoon dog (Nyctereutes procyonoides GRAY, 1834) an invasive, alien canid in Central Europe

Drygala, Frank 16 August 2010 (has links) (PDF)
Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of North-East Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair mates sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young raccoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radiocollared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.
1047

Political economy of intergovernmental grants

Jarocinska, Elena 27 October 2006 (has links)
Esta tesis investiga la economía política de las transferencias intergubernamentales. Se centra en los factores políticos que determinan la asignación de fondos bajo control de gobiernos centrales a las diversas regiones. El primer capítulo, contribuye a este asunto a través de un nuevo análisis de los datos del panel y una medida comprensiva de necesidades de gastos para el caso de Rusia. El segundo capítulo, desarrolla nuevas herramientas metodológicas para analizar sistemas políticos del multi-partido. Estas herramientas permiten medir a votantes cambiantes en dos dimensiones ideológicas usando datos individuales de los estudios electorales. En el tercer capítulo se utilizan las medidas de votantes cambiantes para probar teorías de las políticas distributivas para el caso de España. Este capítulo demuestra que las variables políticas son significativas en la asignación de las subvenciones del estado, y la magnitud del efecto es comparable a la de variables económicas. / This thesis investigates the political economy view of intergovernmental grants. It centers on the political factors that determine allocation of funds under the control of central governments to different regions. The first chapter contributes to this topic by a novel analysis of panel data and a comprehensive measure of expenditure "needs" for the case of Russia. The second chapter develops new methodological tools for analyzing multi-party political systems. These tools allow to measure swing voters on two "ideological" dimensions using individual survey data. In the third chapter the measures of swing voters are used to test theories of distributive politics for the case of Spain. This chapter shows that political variables are significant in the allocation of state subventions, and the magnitude of the effect is comparable to that of economic variables.
1048

Inteligência computacional aplicada na geração de respostas impulsivas bi-auriculares e em aurilização de salas / Computational intelligence applied to binaural impulse responses generation and room auralization

José Francisco Lucio Naranjo 19 May 2014 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Neste trabalho é apresentada uma nova abordagem para obter as respostas impulsivas biauriculares (BIRs) para um sistema de aurilização utilizando um conjunto de redes neurais artificiais (RNAs). O método proposto é capaz de reconstruir as respostas impulsivas associadas à cabeça humana (HRIRs) por meio de modificação espectral e de interpolação espacial. A fim de cobrir todo o espaço auditivo de recepção, sem aumentar a complexidade da arquitetura da rede, uma estrutura com múltiplas RNAs (conjunto) foi adotada, onde cada rede opera uma região específica do espaço (gomo). Os três principais fatores que influenciam na precisão do modelo arquitetura da rede, ângulos de abertura da área de recepção e atrasos das HRIRs são investigados e uma configuração ideal é apresentada. O erro de modelagem no domínio da frequência é investigado considerando a natureza logarítmica da audição humana. Mais ainda, são propostos novos parâmetros para avaliação do erro, definidos em analogia com alguns dos bem conhecidos parâmetros de qualidade acústica de salas. Através da metodologia proposta obteve-se um ganho computacional, em redução do tempo de processamento, de aproximadamente 62% em relação ao método tradicional de processamento de sinais utilizado para aurilização. A aplicabilidade do novo método em sistemas de aurilização é reforçada mediante uma análise comparativa dos resultados, que incluem a geração das BIRs e o cálculo dos parâmetros acústicos biauriculares (IACF e IACC), os quais mostram erros de magnitudes reduzidas. / This work presents a new approach to obtain the Binaural Impulse Responses (BIRs) for an auralization system by using a committee of artificial neural networks (ANNs). The proposed method is capable to reconstruct the desired modified Head Related Impulse Responses (HRIRs) by means of spectral modification and spatial interpolation. In order to cover the entire auditory reception space, without increasing the networks architecture complexity, a structure with multiple RNAs (group) was adopted, where each network operates in a specific reception region (bud). The three major parameters that affect the models accuracy the networks architecture, the reception regions aperture angles and the HRIRs time shifts are investigated and an optimal setup is presented. The modeling error, in the frequency domain, is investigated considering the logarithmic nature of the human hearing. Moreover, new parameters are proposed for error evaluation in the time domain, defined in analogy with some of the well known acoustical quality parameters in rooms. It was observed that the proposed methodology obtained a computational gain of approximately 62%, in terms of processing time reduction, compared to the classical signal processing method used to obtain auralizations. The applicability of the new method in auralizations systems is validated by comparative analysis, which includes the BIRs generation and calculation of the binaural acoustic parameters (IACF and IACC), showing very low magnitude errors.
1049

David and Solomon : investigating the archaeological evidence

Thompson, Lynn 02 1900 (has links)
The historicity of the United Monarchy has recently come under attack. The biblical 'minimalists' say that a reconstruction of ancient Israel is impossible with the sources that we have access to, and the glory and wealth of Solomon's empire is mere fiction. They disregard the Bible as a reliable source, and archaeology because it is mute and open to interpretation. Some scholars have suggested lowering the traditional dates on certain archaeological strata, resulting in an entirely different picture of the tenth century BCE. Other scholars say that the United Monarchy definitely did exist and consider the Bible a valuable historical source. The evidence for the tenth century and the United Monarchy as shown by the Hebrew Bible and archaeology is investigated as well as various key sites in Israel. The conclusion is that the traditional chronology and viewpoint of the United Monarchy still needs to be respected. / Biblical and Ancient Studies / M.A. (Biblical Studies)
1050

Inteligência computacional aplicada na geração de respostas impulsivas bi-auriculares e em aurilização de salas / Computational intelligence applied to binaural impulse responses generation and room auralization

José Francisco Lucio Naranjo 19 May 2014 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Neste trabalho é apresentada uma nova abordagem para obter as respostas impulsivas biauriculares (BIRs) para um sistema de aurilização utilizando um conjunto de redes neurais artificiais (RNAs). O método proposto é capaz de reconstruir as respostas impulsivas associadas à cabeça humana (HRIRs) por meio de modificação espectral e de interpolação espacial. A fim de cobrir todo o espaço auditivo de recepção, sem aumentar a complexidade da arquitetura da rede, uma estrutura com múltiplas RNAs (conjunto) foi adotada, onde cada rede opera uma região específica do espaço (gomo). Os três principais fatores que influenciam na precisão do modelo arquitetura da rede, ângulos de abertura da área de recepção e atrasos das HRIRs são investigados e uma configuração ideal é apresentada. O erro de modelagem no domínio da frequência é investigado considerando a natureza logarítmica da audição humana. Mais ainda, são propostos novos parâmetros para avaliação do erro, definidos em analogia com alguns dos bem conhecidos parâmetros de qualidade acústica de salas. Através da metodologia proposta obteve-se um ganho computacional, em redução do tempo de processamento, de aproximadamente 62% em relação ao método tradicional de processamento de sinais utilizado para aurilização. A aplicabilidade do novo método em sistemas de aurilização é reforçada mediante uma análise comparativa dos resultados, que incluem a geração das BIRs e o cálculo dos parâmetros acústicos biauriculares (IACF e IACC), os quais mostram erros de magnitudes reduzidas. / This work presents a new approach to obtain the Binaural Impulse Responses (BIRs) for an auralization system by using a committee of artificial neural networks (ANNs). The proposed method is capable to reconstruct the desired modified Head Related Impulse Responses (HRIRs) by means of spectral modification and spatial interpolation. In order to cover the entire auditory reception space, without increasing the networks architecture complexity, a structure with multiple RNAs (group) was adopted, where each network operates in a specific reception region (bud). The three major parameters that affect the models accuracy the networks architecture, the reception regions aperture angles and the HRIRs time shifts are investigated and an optimal setup is presented. The modeling error, in the frequency domain, is investigated considering the logarithmic nature of the human hearing. Moreover, new parameters are proposed for error evaluation in the time domain, defined in analogy with some of the well known acoustical quality parameters in rooms. It was observed that the proposed methodology obtained a computational gain of approximately 62%, in terms of processing time reduction, compared to the classical signal processing method used to obtain auralizations. The applicability of the new method in auralizations systems is validated by comparative analysis, which includes the BIRs generation and calculation of the binaural acoustic parameters (IACF and IACC), showing very low magnitude errors.

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