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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.
21

Re-descobrindo ser-si-mesmo: a existencialidade de mulheres praticantes de pole dance

Ferreira, Carolina Fernandes 24 November 2015 (has links)
Submitted by Luan Nogueira (luan_zx_@hotmail.com) on 2016-02-22T15:18:23Z No. of bitstreams: 1 Dissertação - Carolina Fernandes Ferreira.pdf: 1875851 bytes, checksum: 1f1d71cc02c1ed8cd0ac34da6a57c56e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-22T19:35:20Z (GMT) No. of bitstreams: 1 Dissertação - Carolina Fernandes Ferreira.pdf: 1875851 bytes, checksum: 1f1d71cc02c1ed8cd0ac34da6a57c56e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-22T19:43:33Z (GMT) No. of bitstreams: 1 Dissertação - Carolina Fernandes Ferreira.pdf: 1875851 bytes, checksum: 1f1d71cc02c1ed8cd0ac34da6a57c56e (MD5) / Made available in DSpace on 2016-02-22T19:43:33Z (GMT). No. of bitstreams: 1 Dissertação - Carolina Fernandes Ferreira.pdf: 1875851 bytes, checksum: 1f1d71cc02c1ed8cd0ac34da6a57c56e (MD5) Previous issue date: 2015-11-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Physical activity is a trainer for everyday life, promoting sound judgment and situational awareness, enabling reaction in face of environmental changes, and having social relations as a performance mediators. The Pole Dance is a sport that is gaining ground in the media. Therefore, the present study, titled "Re-discovering being-one-self: the existentialism of women pole dance practitioners", is aimed at understanding how pole dance women practitioners mean their existence from the practice of sports. It is a qualitative research, which was developed according to the precepts of the phenomenological method and analysis from the assumptions of the Phenomenology of Merleau-Ponty. Twelve women pole dance practitioners from a studio in the city of Manaus were considered as participants and the data collection was carried out from a guiding question. Through those speeches the following categories of analysis were created: Starting "to pole", Obstacles versus Overcoming , Pre-Concepts, Re-discovering be one-self and "What does pole dance mean for you?". In such analysis, the most diverse experiences were seized on a common practice, in which of them the being-in- the-world of each of these women was verified and how they see themselves and perceive their bodies in interaction with themselves and with the world. It was understood that behind a simple movement, there are countless beings- in- the-world and that the most certain existing fact is individuality / A atividade física é um preparador para a vida cotidiana, promovendo a capacidade de julgamento e percepção da situação, possibilitando reação frente a alterações do ambiente, tendo as relações sociais como mediadores de desempenho. A Pole Dance é uma modalidade esportiva que está ganhando espaço na mídia. Por conseguinte, a presente pesquisa, intitulada “Re-descobrindo ser-si-mesmo: a existencialidade das mulheres praticantes de pole dance”, teve como objetivo compreender como mulheres praticantes de pole dance significam a sua existência a partir da prática da atividade esportiva. É uma pesquisa de natureza qualitativa, que se desenvolveu de acordo com os preceitos do método fenomenológico e a análise a partir dos pressupostos da Fenomenologia de Merleau-Ponty. Foram consideradas como participantes doze mulheres praticantes de pole dance de um estúdio na cidade de Manaus e a obtenção dos dados foi realizada a partir de uma questão norteadora. Através dos discursos foram criadas as categorias de análise: Começando a “polear”, Obstáculos versus Superação, Pré-Conceitos, Re-descobrindo ser-si-mesmo e “O que significa pole dance para você?”. Nelas foram apreendidas as mais diversas experiências sobre uma mesma prática, em que se verificou o ser-no-mundo de cada uma dessas mulheres e como elas se veem e percebem o seu corpo na interação com-si-mesmas e com-o-mundo. Compreendeu-se que por trás de um simples movimento, há inúmeros seres-no-mundo e que a individualidade é o fato mais certo que existe
22

Spektrální charakteristika iontového pole různých druhů ionizorů / Spectral charakteristic of Ion area for different type of ionisors

Novák, Roman January 2009 (has links)
This work deals with issues of explanations and describing of a whole kind of probléme, which appear duiring a generations and measurings of a anionts. I would like to explain and warn for different factors why we should continue with measuring and inventing in this thema. Understanding of a anionts behavior and practice measuring of a ionts area is the most important part of my work, to correctly analyse iont area probléme, or to suggest suitable solution.
23

Řízení inverzního kyvadla programovatelným automatem / Control of real cart pole balancer by PLC

Mitiska, Daniel January 2009 (has links)
This thesis deals with design of inversion pendulum, pole rod balancing on mobile vehicle.In the first part is described projection and realisation of mechanical part of the task, the problems encountered during the projection and eventuallly its final solution. Follows verification of the mechanical and electrical part and testing of possibilities of operating by programated machine.
24

Added CFO Voltages from Fiberglass Poles and its Electrical Degradation

Li, Xiaoyong 14 December 2001 (has links)
THE CRITICAL FLASHOVER (CFO) VOLTAGE OF AN INSULATION STRUCTURE IS COMMONLY USED TO DESCRIBE THE INSULATION STRUCTURE¡¯S LIGHTNING IMPULSE STRENGTH. THE FIBERGLASS DISTRIBUTION POLE WAS RECENTLY INTRODUCED TO POWER DISTRIBUTION SYSTEMS. HOWEVER, VERY LITTLE WORK HAS BEEN DONE ON EITHER THE LIGHTNING IMPULSE CHARACTERISTICS OF DISTRIBUTION LINE STRUCTURES WITH FIBERGLASS POLES OR THE ELECTRICAL DEGRADATION OF FIBERGLASS. THE WORK IN THIS THESIS REPRESENTS THE RESULTS OF A LABORATORY STUDY ON LIGHTNING IMPULSE CHARACTERISTICS OF DISTRIBUTION LINE STRUCTURES WITH FIBERGLASS POLES AND THE ELECTRICAL DEGRADATION OF FIBERGLASS. THE CRITICAL FLASHOVER (CFO) VOLTAGES OF THE FIBERGLASS DISTRIBUTION POLE AS AN INSULATION STRUCTURE ALONE AND ITS COMBINATION WITH VARIOUS INSULATORS WERE EVALUATED. THE ADDED CFO VOLTAGES FROM FIBERGLASS DISTRIBUTION POLES TO BASIC INSULATION COMPONENTS WERE CALCULATED BASED ON THE TEST RESULTS. THE ACCELERATED AGING TESTS AND CORRESPONDING ELECTRICAL EVALUATION TESTS WERE ALSO CONDUCTED TO INVESTIGATE THE ELECTRICAL DEGRADATION OF FIBERGLASS.
25

Ultra-Wideband Antenna Characterization and Modeling

Licul, Stanislav 17 November 2004 (has links)
A new methodology is presented for characterizing an antenna system both in the time and frequency domain with one set of parameters using a singularity expansion method representation. A minimal set of parameter modeling antenna systems using the Matrix-Pencil method has been demonstrated. It has been shown that it is possible to obtain frequency-domain patterns from pole/residue models of antenna realized effective length. Thus, a pole/residue model of the antenna realized effective length presents a complete description in both the time and frequency domains. Once such a model is available, one can obtain the antenna pattern, directivity and gain in the frequency domain and the radiated transient waveform for an arbitrary excitation waveform and an arbitrary antenna orientation. / Ph. D.
26

SPATIAL AND TEMPORAL PATTERNS IN SHORT TERM EMPLOYMENT CHANGE WITHIN THE SOUTHERN ONTARIO URBAN SYSTEM

Stankovic, Dan January 1974 (has links)
"Regional growth theory requires the explicit introduction of two fundamental dimensions - time and space. The time dimension was successfully brought into economic theory with the release of Keynes’ assumption of a constant production capacity. Model building in the field of growth theory of national economics continues to achieve high levels of theoretical sophistication, including the empirical application of rather abstract models. Independent of these striking developments in dynamic analysis was the introduction of the spatial dimension, mainly through the work of Walter Isard in the late 1950's. These two. fundamental innovations, however, failed to be integrated. Growth theory formulated its models for a wonderland of no spatial dimension, and regional science did not bother to introduce the time dimension." (Siebert, 1969, pp. 5 - 6). The importance of incorporating temporal dynamics into building urban and regional planning models is becoming increasingly recognized. Forrester’s (1969) urban dynamics model, which gives a purely temporal, non-spatial simulation model of the city is one example of this line of development. The Lowry (1964) model of urban land use has been given a number of temporal reinterpretations such as the Tomm and Empiric models (Lowry, 1967). A third approach is the work focussing on the spatial transmission and description of business cycle impulses in urban and regional economic systems. The present study falls in line with the last approach. It involves an empirical identification of the variations in the timing and intensity of employment fluctuations existing among cities in Southern Ontario. Economic change or growth in one urban place is viewed as, at least, a partial function of changes taking place elsewhere in the urban system. The structure of urban interdependencies is conditioned by the frictions of distance, by the existence of urban size thresholds and hierarchies and by inter-market, industrial and financial linkages. These spatial relations are examined in reference to growth pole theory and to the literature on economic fluctuations in urban/regional systems. Some spatial considerations in growth pole theory are discussed first, followed by a review of a number of limitations and neglected issues found in the empirical research. Based on this theoretical and empirical review, the study attempts to show how an analysis of urban short run phenomena such as cyclical fluctuations is related to growth pole theoretical constructs and how it is useful in the empirical testing of growth pole processes and in planning applications. A conceptual framework is then outlined, structuring the way economic impulses are generated through national, regional and local mechanisms and transmitted through the urban system and how the impacts of these impulses on urban centres vary in intensity and timing. From this conceptual framework, three analytical procedures for examining certain questions about change in an urban system and for investigating spatial interdependencies in urban short run economic behaviour, are outlined. First, factor analysis as a technique for studying spatial— temporal patterns in the intensity and timing of growth among cities is presented. Second, a model that deals with the decomposition of urban time series data into three components, a long term growth trend, a national cyclical component and a regional component, is presented. Third, a model for testing for spatial-temporal growth trends (polarization trends) at the regional level is developed. Time series data, consisting of monthly industrial composite employment indicies for a five year time period from January, 1968, to December, 1972, for 29 cities in Southern Ontario, are applied to the analytical methodologies. The monthly observations are seasonally, adjusted, using dummy variables and least squares multiple regression. Some concluding statements are made in the final chapter. / Thesis / Master of Arts (MA)
27

Espectroscopia do núcleo 23Mg acima do limiar de decaimento de prótons com interesse para astrofísica nuclear / Spectroscopy of 23Mg nucleus above the proton threshold of interest to nuclear astrophysics

Lara, Alessandro Luiz de 05 November 2018 (has links)
O conhecimento das reações nucleares que ocorrem no interior das estrelas permite estudar como será a evolução destes astros e as relações de abundância entre os isótopos de alguns elementos. Em alguns casos, a detecção de elementos traços pode ser útil para inferir a ocorrência de eventos explosivos, como novas e supernovas. Um destes elementos é o 22Na, cuja abundância depende da reação de captura de próton 22Na(p, ?)23Mg. Assim, o estudo dos estados de ressonância do 23Mg, é importante para compreender o mecanismo de reação e determinar a abundância do 22Na. O núcleo de 23Mg ainda participa do ciclo NeNa na fase AGB da evolução de estrelas de massa média. Com essa motivação propomos o estudo espectroscópico do núcleo 23Mg por meio da reação de transferência 24Mg(3He, 4He)23Mg, cujos dados experimentais foram obtidos no laboratório Tandem-Orsay (França), com o uso de um feixe de 3He de 25 MeV. As ressonâncias de interesse do núcleo 23Mg estudadas nesse trabalho estão compreendidas na faixa de energia de excitação 7.5 MeV a 9.5 MeV. Os estados de ressonância do 23Mg foram populados com a interação do feixe com o alvo de natMg, e as partículas de 4He foram analisadas com o espectrógrafo Split-pole. Os espectros de posição das partículas de 4He foram então calibrados em rigidez magnética, por meio de um polinômio de segunda ordem. Após a calibração os espectros de rigidez magnética foram transformados em espectros de energia de excitação. Nesses espectros pudemos identificar e estudar a presença de contaminantes. Vários estados abaixo e alguns estados acima do limiar de decaimento foram observados e identificados. Dentre os estados acima do limiar estão os estados: 7.586, 7.648, (7.782 e 7.786), 7.855, 8.076, 8.163, 8.420, 8.453, 8.943 e 8.990 MeV do 23Mg. Sendo que apenas os estados 7.586 e 8.163 tem o spin J=5/2+ estabelecido. Ao final apresentamos uma discussã / The knowledge of the nuclear reactions that take place inside the stars allows to study how the evolution of this star will be and the relations of abundance between the isotopes of some elements. In some cases the detection of trace elements can be useful to infer about the occurrence of explosive events, as novae and the supernovae. One of these elements is the 22Na, whose abundance depends on the proton capture reaction 22Na(p, ?)23Mg. The gamma radiation photon with energy 1.275 MeV emitted by 22Na may be a novae type event indicator. Thus, the study of the resonance states of 23Mg is important to understand the mechanism of reaction and determine the 22Na abundance. The nucleus of 23Mg still participate in the cycle NeNa in the AGB phase of the evolution of average stars. With this motivation, we propose to study the spectroscopy of the 23Mg by the 24Mg(3He, 4He)23Mg neutron transfer reaction, whose experimental data were obtained in the Tandem-Orsay facility (France), using the 3He beam of energy 25 MeV. The resonances of interest for this work are in the range of 7.5 MeV up to 9.5 MeV, above the decay threshold for protons. The resonance states of 23Mg were obtained with the interaction of the beam with the natMg target, and the 4He particles were analyzed in a Split-pole spectrograph. The position spectra were then calibrated in magnetic rigidity by means of a second-order polynomial function. The effects of the contaminants were analyzed by converting the spectra into excitation energy, in which it was possible to separate the states 7.586, 7.648, (7.782 e 7.786), 7.855, 8.076, 8.163, 8.420, 8.453, 8.943 e 8.990 MeV of 23Mg. Finally we present a qualitative discussion of the angular distribution for some states and we discuss the possibilities for the future.
28

Automatic Stability Checking for Large Analog Circuits

Mukherjee, Parijat 1985- 14 March 2013 (has links)
Small signal stability has always been an important concern for analog designers. Recent advances such as the Loop Finder algorithm allows designers to detect and identify local, potentially unstable return loops without the need to identify and add breakpoints. However, this method suffers from extremely high time and memory complexity and thus cannot be scaled to very large analog circuits. In this research work, we first take an in-depth look at the loop finder algorithm so as to identify certain key enhancements that can be made to overcome these shortcomings. We next propose pole discovery and impedance computation methods that address these shortcomings by exploring only a certain region of interest in the s-plane. The reduced time and memory complexity obtained via the new methodology allows us to extend automatic stability checking to much larger circuits than was previously possible.
29

Effect of Woodpecker Damage and Wood Decay on Wood Utility Pole Strength

Steenhof, Mark January 2011 (has links)
In many regions of North America, Europe, and Australia, wood utility poles are used as main and secondary structural members for the support of electrical distribution and transmission lines. In the province of Ontario alone there are over 40000 H-frame, 6000 Gulfport, and thousands of single pole structures constructed of over 2 million wood utility poles (Pandey et al. 2010b). Currently, utility companies report an increasing number of woodpecker damage incidents on in-service utility poles (HONI 2010). In addition, many aging poles have woodpecker damage in combination with wood decay. Both these forms of degradation cause strength reductions in utility poles, making their structural integrity questionable. This has raised concerns regarding the safety of utility maintenance workers and the public, and the dependability of the electrical network. In response to these concerns, Hydro One Networks Incorporated (HONI) initiated a research project on the effect of woodpecker damage and wood decay on wood utility pole strength. The objective of the research was to develop methods of quantifying the strength reduction caused by woodpecker damage and wood decay. This information was then used to develop in-service assessment methods for determination of whether pole replacement is necessary when specific levels of woodpecker damage and wood decay are present. By developing better assessment methods, in-service utility poles will not be unnecessarily replaced, reducing maintenance costs. In this study, three analytical models were developed that predicted the theoretical cross-sectional strength reduction caused by the presence of woodpecker damage. A bending failure model was developed since, in the structural design of utility poles, bending moment stresses are known to be the critical design parameter. It was decided that the significance of shear stress in a cross-section should also be considered since the presence of woodpecker damage could cause shear stresses to be a significant parameter. As a result, a shear-bending and a shear failure model was developed to determine the significance of shear stress on cross-section behaviour. These models were developed for analysis purposes and were verified by the subsequent experimental program. A total of 28 new and in-service utility poles were received from HONI for experimental testing. The new poles were received in as-new condition, while the in-service poles received had varying levels of woodpecker damage and wood decay. The poles received were cut into 4.25 m lengths for beam testing. A single new pole and in-service specimen from each pole was tested as a control specimen without woodpecker damage to obtain reference utility pole bending strengths. The remainder of the new pole specimens were mechanically introduced with woodpecker damage, while the remainder of the in-service specimens were tested with natural woodpecker damage. The tested specimens were analyzed and the results were compared with the woodpecker damage analytical model predictions. Results indicated that the effect of woodpecker damage is well modelled by the woodpecker damage analytical models. Overall, the bending failure analytical model was preferable for cross-section analysis due to the accuracy of the model predictions and the simplicity of required calculations. It was evident from the experimental program that the presence of woodpecker damage can severely reduce the strength of utility poles, making replacement necessary according to CSA C22.3 No. 1 Cl. 8.3.1.3 (2006a). In-service specimen experimental results indicated that if wood decay is detected in wood utility poles, severe reduction in wood strength has occurred and the utility pole should be replaced. Analytical and experimental results were used to develop three application methods for determining whether utility pole replacement is necessary due to the presence of woodpecker damage. These three methods include the simplified method, the chart method, and the case-specific method. The simplified method allows determination of whether a utility pole should be replaced based only on knowledge of the most severe level of woodpecker damage present in a pole. The chart method takes into account additional factors such as the diameter of the pole at the location of the woodpecker damage and the width of the hole opening. The case-specific method is advantageous since it accounts for the parameters used in the chart method and allows the location of woodpecker damage along the length of a pole to be accounted for. The simplified and chart methods are preferable since they are relatively simple and easy to implement in the field. The case-specific method requires a full structural analysis of the utility pole in question to be undertaken and is useful for more accurately assessing whether replacement is necessary. These three methods show how the research completed can be used for improved assessment of in-service utility poles resulting in reduced unnecessary pole replacement and maintenance costs.
30

Effect of Woodpecker Damage and Wood Decay on Wood Utility Pole Strength

Steenhof, Mark January 2011 (has links)
In many regions of North America, Europe, and Australia, wood utility poles are used as main and secondary structural members for the support of electrical distribution and transmission lines. In the province of Ontario alone there are over 40000 H-frame, 6000 Gulfport, and thousands of single pole structures constructed of over 2 million wood utility poles (Pandey et al. 2010b). Currently, utility companies report an increasing number of woodpecker damage incidents on in-service utility poles (HONI 2010). In addition, many aging poles have woodpecker damage in combination with wood decay. Both these forms of degradation cause strength reductions in utility poles, making their structural integrity questionable. This has raised concerns regarding the safety of utility maintenance workers and the public, and the dependability of the electrical network. In response to these concerns, Hydro One Networks Incorporated (HONI) initiated a research project on the effect of woodpecker damage and wood decay on wood utility pole strength. The objective of the research was to develop methods of quantifying the strength reduction caused by woodpecker damage and wood decay. This information was then used to develop in-service assessment methods for determination of whether pole replacement is necessary when specific levels of woodpecker damage and wood decay are present. By developing better assessment methods, in-service utility poles will not be unnecessarily replaced, reducing maintenance costs. In this study, three analytical models were developed that predicted the theoretical cross-sectional strength reduction caused by the presence of woodpecker damage. A bending failure model was developed since, in the structural design of utility poles, bending moment stresses are known to be the critical design parameter. It was decided that the significance of shear stress in a cross-section should also be considered since the presence of woodpecker damage could cause shear stresses to be a significant parameter. As a result, a shear-bending and a shear failure model was developed to determine the significance of shear stress on cross-section behaviour. These models were developed for analysis purposes and were verified by the subsequent experimental program. A total of 28 new and in-service utility poles were received from HONI for experimental testing. The new poles were received in as-new condition, while the in-service poles received had varying levels of woodpecker damage and wood decay. The poles received were cut into 4.25 m lengths for beam testing. A single new pole and in-service specimen from each pole was tested as a control specimen without woodpecker damage to obtain reference utility pole bending strengths. The remainder of the new pole specimens were mechanically introduced with woodpecker damage, while the remainder of the in-service specimens were tested with natural woodpecker damage. The tested specimens were analyzed and the results were compared with the woodpecker damage analytical model predictions. Results indicated that the effect of woodpecker damage is well modelled by the woodpecker damage analytical models. Overall, the bending failure analytical model was preferable for cross-section analysis due to the accuracy of the model predictions and the simplicity of required calculations. It was evident from the experimental program that the presence of woodpecker damage can severely reduce the strength of utility poles, making replacement necessary according to CSA C22.3 No. 1 Cl. 8.3.1.3 (2006a). In-service specimen experimental results indicated that if wood decay is detected in wood utility poles, severe reduction in wood strength has occurred and the utility pole should be replaced. Analytical and experimental results were used to develop three application methods for determining whether utility pole replacement is necessary due to the presence of woodpecker damage. These three methods include the simplified method, the chart method, and the case-specific method. The simplified method allows determination of whether a utility pole should be replaced based only on knowledge of the most severe level of woodpecker damage present in a pole. The chart method takes into account additional factors such as the diameter of the pole at the location of the woodpecker damage and the width of the hole opening. The case-specific method is advantageous since it accounts for the parameters used in the chart method and allows the location of woodpecker damage along the length of a pole to be accounted for. The simplified and chart methods are preferable since they are relatively simple and easy to implement in the field. The case-specific method requires a full structural analysis of the utility pole in question to be undertaken and is useful for more accurately assessing whether replacement is necessary. These three methods show how the research completed can be used for improved assessment of in-service utility poles resulting in reduced unnecessary pole replacement and maintenance costs.

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