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The Global ETD Search service is a free service for researchers
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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.
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Showing 11 to 20 of 20 (0.032 seconds)| 11 |
Adolescents' Perceptions of Rejection Status and Potentially Rejecting SituationsBaker, Tracie R. 08 November 2011 (has links)
No description available.
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Design and implementation of band rejected antennas using adaptive surface meshing and genetic algorithms methods : simulation and measurement of microstrip antennas with the ability of harmonic rejection for wireless and mobile applications including the antenna design optimisation using genetic algorithmsBinmelha, Mohammed Saeed January 2013 (has links)
With the advances in wireless communication systems, antennas with different shapes and design have achieved great demand and are desirable for many uses such as personal communication systems, and other applications involving wireless communication. This has resulted in different shapes and types of antenna design in order to achieve different antenna characteristic. One attractive approach to the design of antennas is to suppress or attenuate harmonic contents due to the non-linear operation of the Radio Frequency (RF) front end. The objectives of this work were to investigate, design and implement antennas for harmonic suppression with the aid of a genetic algorithm (GA). Several microstrip patch antennas were designed to operate at frequencies 1.0, 1.8 and 2.4 GHz respectively. The microstrip patch antenna with stub tuned microstrip lines was also employed at 1.0 and 1.8 GHz to meet the design objectives. A new sensing patch technique is introduced and applied in order to find the accepted power at harmonic frequencies. The evaluation of the measured power accepted at the antenna feed port was done using an electromagnetic (EM) simulator, Ansoft Designer, in terms of current distribution. A two sensors method is presented on one antenna prototype to estimate the accepted power at three frequencies. The computational method is based on an integral equation solver using adaptive surface meshing driven by a genetic algorithm. Several examples are demonstrated, including design of coaxially-fed, air-dielectric patch antennas implanted with shorting and folded walls. The characteristics of the antennas in terms of the impedance responses and far field radiation patterns are discussed. The results in terms of the radiation performance are addressed, and compared to measurements. The presented results of these antennas show a good impedance matching at the fundamental frequency with good suppression achieved at the second and third harmonic frequencies.
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Purificação de rejeitos de lascas de quartzo das industrias de silicio / Purification of quartz lascas rejected by silicon industriesArgonz, Raquel 14 February 2001 (has links)
Orientador: Carlos K. Suzuki / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-31T20:22:15Z (GMT). No. of bitstreams: 1
Argonz_Raquel_D.pdf: 6011460 bytes, checksum: 288a8671c5c8ed96310d3c57226ce9c8 (MD5)
Previous issue date: 2001 / Resumo: O Brasil é na atualidade um dos principais produtores de silício para o mundo, sendo que a quantidade de quartzo extraído para a sua produção incluindo o ferro-silício, é da ordem de 2 milhões de toneladas/ano. Para a obtenção do quartzo destinado à redução carbotérmica em silício, nos diversos estágios de extração, britagem, seleção, transporte, e lavagem, cerca de 300.000 toneladas/ano de lascas de quartzo tomam-se rejeitos. Neste trabalho foi desenvolvida uma metodologia ambientalmente correta, denominada "quench-Ieaching" e "crush-leaching", que se utiliza da lixiviação aquosa para a purificação deste material. Os resultados mostram que ocorre uma remoção efetiva de impurezas majoritárias nas lascas de quartzo, tais como, AI, Fe, Na, K, Ca, Mn, ..., dando-lhe uma pureza de 99,9% de SI 'O IND 2'. Uma comparação com diversos insumos de quartzo produzidos no exterior para uso em tecnologia avançada, como para produção de sílica vítrea translucente e "fillers" de "micro-chips", revela que este material purificado com esta tecnologia toma-se de qualidade equivalente ao pó de quartzo internacional / Abstract: Nowadays, Brazil is one of the main silicon metal and iron-silicon producer in the world. But on the other hand, the amount of natural quartz that has been extracted for this purpose is up to 2 milliontons/year. The key-point is the large quantity of rejected quartz lascas, approximately 300,000 tons/year, generated during the various stages of extraction, crushing, selection, transportation, and washing. A new environrnentally mendly purification methodology denominated "quench-Ieaching" and "crush-leaching, that only uses aqueous leaching, has been developed. The result shows an effective elimination of major quartz impurities, such as Al, Fe, Na, K, Ca, Mn, ... , that transforms this rejected material into a 99.9% purity SI 'O IND 2'. The quality of this material is as high as the quartz powder commercially available in the intemational market for use as "fillers" and translucent silica glass raw material for semiconductor industries / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica
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Design and implementation of band rejected antennas using adaptive surface meshing and genetic algorithms methods. Simulation and measurement of microstrip antennas with the ability of harmonic rejection for wireless and mobile applications including the antenna design optimisation using genetic algorithms.Bin-Melha, Mohammed S. January 2013 (has links)
With the advances in wireless communication systems, antennas with different shapes and design have achieved great demand and are desirable for many uses such as personal communication systems, and other applications involving wireless communication. This has resulted in different shapes and types of antenna design in order to achieve different antenna characteristic. One attractive approach to the design of antennas is to suppress or attenuate harmonic contents due to the non-linear operation of the Radio Frequency (RF) front end.
The objectives of this work were to investigate, design and implement antennas for harmonic suppression with the aid of a genetic algorithm (GA). Several microstrip patch antennas were designed to operate at frequencies 1.0, 1.8 and 2.4 GHz respectively. The microstrip patch antenna with stub tuned microstrip lines was also employed at 1.0 and 1.8 GHz to meet the design objectives.
A new sensing patch technique is introduced and applied in order to find the accepted power at harmonic frequencies. The evaluation of the measured power accepted at the antenna feed port was done using an electromagnetic (EM) simulator, Ansoft Designer, in terms of current distribution. A two sensors method is presented on one antenna prototype to estimate the accepted power at three frequencies.
The computational method is based on an integral equation solver using adaptive surface meshing driven by a genetic algorithm. Several examples are demonstrated, including design of coaxially-fed, air-dielectric patch antennas implanted with shorting and folded walls. The characteristics of the antennas in terms of the impedance responses and far field radiation patterns are discussed. The results in terms of the radiation performance are addressed, and compared to measurements. The presented results of these antennas show a good impedance matching at the fundamental frequency with good suppression achieved at the second and third harmonic frequencies. / Home government
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Multiple Band-Notched UWB Antenna With Band-Rejected Elements Integrated in the Feed LineZhu, F., Gao, S., Ho, A.T.S., Abd-Alhameed, Raed, See, Chan H., Brown, T.W.C., Li, J., Wei, G., Xu, J. January 2013 (has links)
No / To mitigate potential interferences with coexisting wireless systems operating over 3.3-3.6 GHz, 5.15-5.35 GHz, or 5.725-5.825 GHz bands, four novel band-notched antennas suitable for ultra-wideband (UWB) applications are proposed. These include UWB antennas with a single wide notched band, a single narrow notched band, dual notched bands, and triple notched bands. Each antenna comprises a half-circle shaped patch with an open rectangular slot and a half-circle shaped ground plane. Good band-notched performance is achieved by using high permittivity and low dielectric loss substrate, and inserting quarter-wavelength horizontal/vertical stubs or alternatively embedding quarter-wavelength open-ended slots within the feed line. The results of both simulation and measurement confirm that the gain suppression of the single and multiple band-notched antennas in each desired notched band are over 15 dB and 10 dB, respectively. The radiation pattern of the proposed triple band-notched design is relatively stable across the operating frequency band.
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Educator perceptions of the implementation of integrated quality management systems (IQMS) in further education and training colleges in South Africa / Karnagie Pillay.Pillay, Karnagie January 2010 (has links)
The purpose of this study was to investigate educator perceptions of the implementation of Integrated Quality Management Systems (IQMS) in Further Education and Training (FET) Colleges in South Africa. Quality in education is presently put more firmly on the agenda not withstanding the fact that a vast range of literature is available to support the process of improving the quality in education. The department of education has made many attempts to introduce an effective appraisal system in support of quality education only to find that the previous appraisal systems were rejected by the educator force for the mere fact that it was perceived as a form of inspection and supervision rather than for development purposes.
This study also focuses on a review of the integrated quality management system (IQMS), of its purpose, guidelines and its subsequent implementation in FET colleges in South Africa in 2004. The primary focus of the discussion is on the processes, the methods, the guiding principles and the pitfalls of the implementation of quality management systems in educational organizations To guide this discussion literature reviews on quality, quality education, quality management and quality management systems were undertaken.
The empirical study entailed gleaning information from a structured questionnaire which was distributed to a sample group of lecturers at Sedibeng College for FET in the Gauteng Province. The questions were structured in a manner to gain information about the understanding of the operational principles of quality management, the aims and guiding principles of IQMS, the importance of quality control and the external relationships of the college. The major finding emanating from this study was that there was a need for intensive training in IQMS, thus a management's strategy for ensuring that IQMS is effectively implemented was proposed. The overall recommendation arising from this study includes ensuring that management designs a quality manual to guide the process of quality assurance. / Thesis (M.Ed. (Education Management))--North-West University, Vaal Triangle Campus, 2010.
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Educator perceptions of the implementation of integrated quality management systems (IQMS) in further education and training colleges in South Africa / Karnagie Pillay.Pillay, Karnagie January 2010 (has links)
The purpose of this study was to investigate educator perceptions of the implementation of Integrated Quality Management Systems (IQMS) in Further Education and Training (FET) Colleges in South Africa. Quality in education is presently put more firmly on the agenda not withstanding the fact that a vast range of literature is available to support the process of improving the quality in education. The department of education has made many attempts to introduce an effective appraisal system in support of quality education only to find that the previous appraisal systems were rejected by the educator force for the mere fact that it was perceived as a form of inspection and supervision rather than for development purposes.
This study also focuses on a review of the integrated quality management system (IQMS), of its purpose, guidelines and its subsequent implementation in FET colleges in South Africa in 2004. The primary focus of the discussion is on the processes, the methods, the guiding principles and the pitfalls of the implementation of quality management systems in educational organizations To guide this discussion literature reviews on quality, quality education, quality management and quality management systems were undertaken.
The empirical study entailed gleaning information from a structured questionnaire which was distributed to a sample group of lecturers at Sedibeng College for FET in the Gauteng Province. The questions were structured in a manner to gain information about the understanding of the operational principles of quality management, the aims and guiding principles of IQMS, the importance of quality control and the external relationships of the college. The major finding emanating from this study was that there was a need for intensive training in IQMS, thus a management's strategy for ensuring that IQMS is effectively implemented was proposed. The overall recommendation arising from this study includes ensuring that management designs a quality manual to guide the process of quality assurance. / Thesis (M.Ed. (Education Management))--North-West University, Vaal Triangle Campus, 2010.
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[en] ARTHUR RAMOS AND THE PROBLEM CHILD AS A REJECTED ONE: PSYCHOANALYSIS, CIVILIZATION AND SCHOOL MENTAL HYGIENE IN THE ANCIENT FEDERAL DISTRICT (1934-1939) / [pt] ARTHUR RAMOS E A CRIANÇA-PROBLEMA COMO CRIANÇA ESCORRAÇADA: PSICANÁLISE, CIVILIZAÇÃO E HIGIENE MENTAL ESCOLAR NO ANTIGO DISTRITO FEDERAL (1934-1939)CATIA REGINA PAPADOPOULOS 28 May 2019 (has links)
[pt] Esta dissertação tem por objetivo pensar sobre a criança escorraçada como
criança-problema no ponto de vista de Arthur Ramos e sua relação com a higiene
mental, civilização, família e escola. Compreende o período de 1934 a 1939
tempo em que funcionou o Serviço de Ortofrenia e Higiene Mental (S.O.H.M.) do
Instituto de Pesquisas Educacionais chefiado pelo médico, a convite de Anísio
Teixeira, que era o Diretor do Departamento de Educação da Secretaria Geral de
Educação e Cultura do Distrito Federal à época. Tinha como finalidade a
organização de trabalhos de cunho preventivo e corretivo, atendendo e tratando os
possíveis problemas psíquicos da criança no lar e na escola e suas dificuldades
com a aprendizagem, atuando nas escolas públicas do ensino primário do Distrito
Federal, mais precisamente, nas Escolas Experimentais. Foram utilizadas fontes
documentais como os livros sobre o assunto, os impressos de vulgarização
dirigidos aos professores e famílias, todos de autoria de Arthur Ramos, além de
reportagens de jornais e revistas de grande circulação no País, inquéritos dirigidos
às diretoras e professoras das Escolas Experimentais, correspondências, estudos
realizados pelo médico, bem como as fichas de observação comportamental de
alunos das referidas Escolas oriundas do S.O.H.M. Este estudo procura responder
as seguintes questões: Qual a importância da psicanálise e da higiene mental
escolar para a transformação da sociedade brasileira em sociedade civilizada?
Quem era a criança escorraçada como criança-problema e como a higiene mental
escolar através da psicanálise contribuiu no sentido de tentar modificar o
comportamento desajustado e a dificuldade com a aprendizagem apresentados por
elas? De que forma a higiene mental escolar buscou orientar família e escola em
relação à criança escorraçada? Para efeito de reflexão, tomou-se por base a
abordagem histórica desenvolvida através do entrelaçamento da análise dos
citados documentos com o conteúdo bibliográfico, em uma perspectiva teórica
baseada na concepção de Norbert Elias sobre o processo civilizatório, na visão de
Sigmund Freud sobre as relações entre o indivíduo e o que ele denominou a
“civilização” e a higiene mental como forma de tratar as neuroses em decorrência
da civilização, buscando entender as concepções de Arthur Ramos sobre esses
processos. Constatou-se que, para Ramos, a base para que o país fosse civilizado e
preparado para o progresso estava no cuidado com a criança através da higiene
mental escolar e preceitos da psicanálise, bem como nas orientações dedicadas à
família e escola, a fim de esclarecer as consequências nefastas do escorraçamento
infantil. / [en] This paper has the purpose of thinking about the rejected child as a problem
one according to Arthur Ramos point of view and the relationship with mental
hygiene, civilization, family and school. All this was based on the period between
1934 and 1939 which the Ortofrenia and the Mental Hygiene of the Institute of
Educational Research worked and was run by the doctor invited by Anísio
Teixeira who was the Director of the Education Department of the General
Department of Education and Culture of the Federal District at that time. Its aim
was the organization of assignments based on prevention and correction, dealing
and treating the possible psychic problems of the child at home and at school and
his difficulties in learning, acting in the Public Primary Schools of the Federal
District, more precisely in the Experimental Schools. Documented sources were
used such as books concerning the subject, the leaflets of vulgarization addressed
to the teachers and the family, all of them were the authorship of Arthur Ramos,
besides the newspaper and magazine articles of great circulation in the country,
investigations headed for the directors and teachers of the Experimental Schools,
correspondences, studies carried out by the doctor, as well as files based on
behavioral observation of the students from the referred schools that came from
the S.O.H.M. This study tries to answer the following questions: What s the
importance of Psychoanalysis and the School Mental Hygiene for the changing of
the Brazilian society into a civilized one? Who was the rejected child considered
as a problem one and how the School Mental Hygiene through Psychoanalysis
contributed to change the misfit behavior and the difficulty in learning presented
by them? How did the School Mental Hygiene contribute to guide the family and
the school in relation to the problem child? As a way of reflecting all this, it was
taken into consideration a historical approach developed through the conjunction
of the analysis of the mentioned documents with the bibliographic content in a
theoretical perspective based on Norbert Elias opinion about the civilized
process, according to Sigmund Freud about the relationships among the individual
and what he called civilization and the mental hygiene as a mean of treating
neurosis as a result of the civilization, in order to understand Arthur Ramos
concepts of these proceedings. It was noticed that in Ramos opinion, the basis for
the country to become civilized and prepared for the progress was centered on the
care with the child through School Mental Hygiene and the rules of
Psychoanalysis, as well as the orientations dedicated to the family and the school,
as to clarify the tragic consequences of a child s rejection.
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Parental Report of Medication Acceptance Among Youth: Implications for Every Day PracticePolaha, Jodi, Dalton, William T., III, Lancaster, Blake M. 01 November 2008 (has links)
No description available.
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Evaluation of Target Tracking Using Multiple Sensors and Non-Causal AlgorithmsVestin, Albin, Strandberg, Gustav January 2019 (has links)
Today, the main research field for the automotive industry is to find solutions for active safety. In order to perceive the surrounding environment, tracking nearby traffic objects plays an important role. Validation of the tracking performance is often done in staged traffic scenarios, where additional sensors, mounted on the vehicles, are used to obtain their true positions and velocities. The difficulty of evaluating the tracking performance complicates its development. An alternative approach studied in this thesis, is to record sequences and use non-causal algorithms, such as smoothing, instead of filtering to estimate the true target states. With this method, validation data for online, causal, target tracking algorithms can be obtained for all traffic scenarios without the need of extra sensors. We investigate how non-causal algorithms affects the target tracking performance using multiple sensors and dynamic models of different complexity. This is done to evaluate real-time methods against estimates obtained from non-causal filtering. Two different measurement units, a monocular camera and a LIDAR sensor, and two dynamic models are evaluated and compared using both causal and non-causal methods. The system is tested in two single object scenarios where ground truth is available and in three multi object scenarios without ground truth. Results from the two single object scenarios shows that tracking using only a monocular camera performs poorly since it is unable to measure the distance to objects. Here, a complementary LIDAR sensor improves the tracking performance significantly. The dynamic models are shown to have a small impact on the tracking performance, while the non-causal application gives a distinct improvement when tracking objects at large distances. Since the sequence can be reversed, the non-causal estimates are propagated from more certain states when the target is closer to the ego vehicle. For multiple object tracking, we find that correct associations between measurements and tracks are crucial for improving the tracking performance with non-causal algorithms.
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