Travelling wave fault locators (TWFL) have the possibility to get rid of the limitation of typical locators based on the 50Hz impedance. Their principles were invented in the early 1900's, but only recently became economically viable. Some TWFL devices are now commercialized.Despite the recent commercialization of TW fault locators, actual field experience of TWFL is hard to acquire and rarely presented in the literature. Due to this, most studies are based on simplified simulation models.Practical experience in the form of TW records are important. It is the basis to understand the practical difficulties of applying TWFL algorithms. It is also necessary to illustrate the simulations limitations, and to test algorithms on real records.The work performed in this thesis was supported by Siemens with the hope to develop TWFL devices based on the results. The aim of the work was first to acquire experience in the practical side of TWs and their recording in substations. Based on this practical experience, the second objective was to study a TWFL that includes a new method for wave detection: the pattern recognition algorithm (PRA). The practical experience was acquired with a measurement campaign performed in the Belgian transmission network, and with laboratory tests that reproduce the measurements of currents inside a substation.Fault records suitable to TW studies were acquired during the measurement campaign, and are analysed in this report. The fault records and the laboratory tests highlighted and characterized the impact of the substation measurements on the waves recorded. Modelling those measurement systems is shown to improve the accuracy of the simulation tools.This report also presents a theoretical development of the PRA. The algorithm is adapted to take into account the practical difficulties previously analysed. An applicable version of the algorithm is proposed and tested. The algorithm proposal provides a precision better than 300m when applied to the simulation models. This precision varies with the set of parameters used, with the line topology, and with the fault location. On the field record acquired, the algorithm provides the fault location with a precision of 110m.A prototype has been developed by Siemens, and some devices have been installed at the end of this thesis. The TW records that will be acquired by those prototypes will provide a significant help in continuing the work presented in this report. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

Made available in DSpace on 2014-10-09T12:34:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:48Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:08/05286-1

Made available in DSpace on 2014-10-09T12:34:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:48Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho apresenta o desenvolvimento de uma plataforma para o estudo teórico e experimental de dispositivos amplificadores de micro-ondas do tipo válvula de ondas progressivas (TWT). A plataforma é composta por um modelo matemático e uma bancada de testes. O modelo matemático descreve a TWT como uma linha de transmissão acoplada a um feixe eletrônico unidimensional, onde as forças de carga espacial AC e DC são calculadas auto consistentemente, eliminando-se a necessidade de um cálculo separado para o fator de redução de carga espacial. O modelo matemático deu origem a dois códigos para a simulação da TWT. Ambos foram comparados com resultados experimentais e teóricos disponíveis na literatura especializada para uma pré-validação. O nível de concordância entre os presentes resultados e aqueles de referência foi acima de 90%, o que atendeu as expectativas de exatidão do modelo, tendo em vista que nem todos os parâmetros de entrada estavam disponíveis na referência. A bancada de testes construída é composta por uma TWT com banda de operação de 6,0 a 18 GHz e potência saturada máxima em torno de 55 dBm (316 W) em 13 GHz, um circuito de polarização para a mesma e a instrumentação necessária para a realização das medidas pertinentes aos amplificadores de potência. A TWT em questão foi caracterizada segundo seu comportamento mono-sinal e multi-sinal. As curvas de ganho e potência foram obtidas em função da frequência utilizando a voltagem de aceleração do feixe eletrônico e a potência de entrada como parâmetros. As curvas de transferência de potência, de fase e compressão de ganho foram obtidas para frequências escolhidas ao longo da banda, tendo novamente a voltagem de aceleração como parâmetro. Adicionalmente, a produção de produtos de intermodulação de terceira ordem foi caracterizada no ponto de 1 dB de compressão de ganho ao longo da banda analisada. Um teste de linearização por injeção de sinais, que estava previsto no plano de trabalho, não apresentou o desempenho esperado devido a problemas no funcionamento do circuito linearizador. Esses problemas foram analisados e listou-se uma série de passos para saná-los. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:08/05286-1

A cochlear implant is a prosthetic device that can provide severe-to-profoundly deaf individuals with partially restored hearing. It emulates the function of a normal cochlea through combined functioning of externally situated electronics and an electrode array surgically implanted into the cochlea. Speech coding strategies implemented in speech processors aim to stimulate the auditory nerve in a way similar to that of a normal working cochlea by modelling the way the cochlea processes sound. Current speech processing strategies rely on the tonotopicity of the cochlea, i.e. the relation between distance from the base of the cochlea and the specific frequency that causes the highest amplitude of deflection at the specific point. The phenomenon of the travelling wave on the basilar membrane is thus reduced to its point or points of maximal deflection. In this study, the behaviour along the full length of the basilar membrane will be investigated in the time domain, i.e. the deflection along the whole membrane for any point in time, in order to evaluate the relevance of the travelling wave in coding sound in a cochlear implant system. The additional information acquired by emulating the motion of the fluid and the basilar membrane in the cochlea, will be transmitted to the recipient in electrical stimulus patterns, to assess whether it provides recipients of cochlear implants with better pitch perception. It will be shown that for the individuals that partook in the experiments, improvement of discrimination around 100 Hz were obtained when compared to current speech coding strategies like the advanced combination encoder (ACE) speech coding strategy in the same recipient. / Dissertation (MEng (Bio-Engineering))--University of Pretoria, 2007. / Electrical, Electronic and Computer Engineering / unrestricted

This thesis deals with selected foreign journeys of Czech and Austrian nobility in the second half of the 18th and at the beginning 19th centuries and their influences and impacts. In addition to the general passages devoted to the travelling of nobility from the 16th to the middle of the 18th centuries and to the expeditions carried out during the period under review, attention is paid to five persons who have been divided into three groups based on their activities influenced by experience gained in foreign countries. The first of the circuits is connected with creating of landscape parks inspired by the ideas of 18th -century philosophy and expeditions to Great Britain and German territory, where the first picturesque gardens appeared. The relationship between travel and landscaping of the second half of the 18th and early 19th centuries is illustrated by the example of Johann Rudolf Czernin of Chudenice and his parks in Krásný Dvůr, Jemčina, Chudenice and Petrohrad or Alois I. Josef of Liechtenstein, whose name is connected with the arrangement of Lednice-Valtice area. Scientific motivated journeys represent the second group. Leopold I. Berchtold of Uherčice, who collected his knowledge of medicine and actively helped others during his journeys, was chosen as a suitable representative. The...

The purpose of this thesis is to make an exploratory study of the British Columbia Mainland Travelling Child Guidance Clinic. One of the main goals is a more definitive statement and clarification of the current functions and services of the clinic. The study includes: (1) A description of travelling child guidance clinics generally, in terms of underlying theory and assumptions, historical development, and current problems and functioning; (2) A brief description of the travelling child guidance services in Canada; (3) A detailed description of the British Columbia Mainland Travelling Child Guidance Clinic: a. its historical development; b. its stated functions and goals; c. its operation "in the field." The above includes material drawn directly from a sample of clinic files, which describes: the characteristic group of clients referred for individual service; problems seen by the referral sources as indicating the need of clinical assessment and help; the channels of referral and presentation to the clinic; the professional members of the community who, through attendance at case conference, come into direct contact with clinical concepts and knowledge about the understanding and treatment within the community of behavior disorders in children, and general mental health methods in the alleviation and prevention of further similar difficulties; and the recommendations made for such community treatment of the disorder. A questionnaire circulated to all Social Welfare Branches indicated the field offices' concept of the effectiveness and adequacy of clinical services. The British Columbia Mainland Travelling Clinic has achieved a good beginning. Staff exigencies in both the clinic and the field have made ideal objectives impossible to achieve. The addition of another travelling clinic team together with more field personnel will alter this criticism. The success of any such undertaking will always depend on harmonious relationships among clinic staff, field health and welfare staff, and other citizens in the communities. / Arts, Faculty of / Social Work, School of / Graduate

The Tour Construction Framework (TCF) integrates both global and local heuristics in a complementary framework in order to efficiently solve the Travelling Salesman Problem (TSP). Most tour construction heuristics are strictly local in nature. However, the experimental method presented in this research includes a global heuristic to efficiently solve the TSP. The Global Path (GP) component and Super Node (SN) component comprise the TCF. Each component heuristic is tuned with one or more parameters. Genetic Algorithms (GA) are used to train the collection of parameters for the TCF components on subsets of benchmark TSPs. The GA results are used to run the TCF on the full TSP instances. The performance of the TCF is evaluated for speed, accuracy, and computational complexity, and it is compared against six mainstream TSP solvers: Lin-Kernighan-Helsgaun (LKH-2), 2-Opt, Greedy, Boruvka, Quick-Boruvka, and Nearest Neighbor. The empirical study demonstrates the effectiveness of the TCF in achieving near-optimal solutions for the TSP with reasonable costs.

This thesis deals with a solution of lifting equipment for sheet metal samples handling. Facility will be part of an automatic production line for semi-finished test specimens for testing the mechanical properties of sheet metals. The options of solutions discussed in this thesis is performed that choice which should be the concept of lifting equipment. Course work cycle of the selected concept is designed, so that material flow provided by the facility meets requirements of the production line. Calculations for the design parts of the main cylinder and the running gear are carried out using a set of parameters and then strength check of steel construction follows. The 3D model of the manipulator, the manipulator assembly drawings and layout drawings of the production line are annexes of this work.

This thesis deals with proposal hoisting device of travelling crab with lifting capacity of 20000 kg for placement in the scrap yard foundries. The main objective is design of bearing elements of cable system (choice of ropes, pulleys, rope drum), strenght calculation block and a proposal to operate the hoisting device (engine, transmission and brake). It also deals with the proposal propel cats (engine, transmission, brakes, wheel load). Drawing documentation contains a set of trolleys, cable drum assembly weldments and detail spigot cable drum.

No / This paper presents a new class of heuristics which embed an exact algorithm within the framework of a local search heuristic. This approach was inspired by related heuristics which we developed for a practical problem arising in electronics manufacture. The basic idea of this heuristic is to break the original problem into small subproblems having similar properties to the original problem. These subproblems are then solved using time intensive heuristic approaches or exact algorithms and the solution is re-embedded into the original problem. The electronics manufacturing problem where we originally used the embedded local search approach, contains the Travelling Salesman Problem (TSP) as a major subproblem. In this paper we further develop our embedded search heuristic, HyperOpt, and investigate its performance for the TSP in comparison to other local search based approaches. We introduce an interesting hybrid of HyperOpt and 3-opt for asymmetric TSPs which proves more efficient than HyperOpt or 3-opt alone. Since pure local search seldom yields solutions of high quality we also investigate the performance of the approaches in an iterated local search framework. We examine iterated approaches of Large-Step Markov Chain and Variable Neighbourhood Search type and investigate their performance when used in combination with HyperOpt. We report extensive computational results to investigate the performance of our heuristic approaches for asymmetric and Euclidean Travelling Salesman Problems. While for the symmetric TSP our approaches yield solutions of comparable quality to 2-opt heuristic, the hybrid methods proposed for asymmetric problems seem capable of compensating for the time intensive embedded heuristic by finding tours of better average quality than iterated 3-opt in many less iterations and providing the best heuristic solutions known, for some instance classes.