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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.
91

Astrofotografia como estratégia no ensino da astronomia / Astrophotography as a strategy in the teaching of astronomy

Amaral, Jose Antonio do 15 March 2019 (has links)
Nesta dissertação, a observação do céu noturno utilizando como instrumento câmeras fotográficas comuns, sem qualquer pretensão profissional, adquire uma dimensão importante como instrumento de apoio ao Ensino de Astronomia, permitindo que estudantes de escolas públicas, ou qualquer pessoa interessada em aprender astronomia, tenha fácil acesso, uma vez que instrumentos óticos como telescópios, são acessíveis a bem poucos. Sob este ponto de vista, é vital oferecer aos estudantes da escola básica e a toda e qualquer pessoa interessada em ciências, oportunidade de participarem de atividades didáticas através da fotografia do céu noturno, resgatando assim o hábito latente de olhar para céu, esquecido pelas novas gerações, vítimas da poluição atmosférica e luminosa, fruto de nossa tecnologia mal dimensionada. O objetivo é incentivar o interesse pela astronomia, estabelecendo um contato sistemático deles com o céu noturno, despertando em cada um a questão fundamental: qual posição ocupamos no contexto do Universo. Este trabalho se preocupa principalmente em proporcionar estratégias acessíveis para fotografar o Céu e de como tratar sobre propostas didáticas para a Fotografia do Céu, utilizando equipamentos simples. Nosso objeto de estudo partiu de uma análise dos conteúdos de astronomia presentes na grade de Ensino Médio das escolas administradas pelo Centro Paula Souza, vinculados aos Parâmetros Curriculares Nacionais. Essa avaliação se apoiou em dois pontos de vista. No primeiro a análise se deu a partir dos conteúdos de astronomia presentes nos livros didáticos adotados pelas escolas para o triênio 2018/2019/2020, alinhados com os Parâmetros Curriculares Nacionais e a grade do ensino médio nas escolas técnicas. O segundo ponto de vista se deu através de uma pesquisa on-line com os estudantes dessas escolas, avaliando o percentual desses conteúdos a que eles efetivamente tiveram contato. Para subsidiar a análise desses percentuais, executamos um estudo sobre o conteúdo de Astronomia, na qual foram elencadas cinco questões, ligadas à proposição de temas abordados pelos professores das disciplinas que contém o tema Astronomia História da Astronomia; Sistema Solar; Estações Climáticas; Sistema Terra-Lua-Sol e Constelações do Hemisfério Sul. Os resultados mostram que, apesar da coerência entre os Parâmetros Curriculares Nacionais e a grade do ensino médio analisados, um percentual significativo de estudantes disseram não terem tido contato com um ou mais temas. A pesquisa serviu como norteadora da necessidade de elaboração e da aplicação de um material didático composto por atividades e oficinas que, utilizando a fotografia do céu noturno, a experimentação e construção de materiais didáticos, atuou como catalizador do aprendizado, reforçando esses conteúdos, utilizando as muitas formas de abordar os conceitos contidos no ensino médio, estimulando os estudantes e até mesmo professores a refletir sobre como nos relacionamos e aprendemos sobre o Universo. / In this work, the observation of the Night Sky using common photographic cameras as instrument, without any professional pretension, acquires an important dimension as a support tool for Astronomy Teaching, allowing students from public schools, or anyone interested in learning astronomy, to have easy access, since optical instruments such as telescopes are accessible to very few people. Under this point of view, it is vital to offer to students of elementary school, and to anybody interested in sciences, the opportunity to participate in didactic activities through photographs of the Night Sky, recovering therefore the habit of looking at the sky, forgotten by the new generations, victims of the atmospheric and luminous pollution, fruit of our ill-directed technology. The goal is to rise the interest for astronomy, establishing a systematic contact with the Night Sky, waking up in each one the fundamental question: which position do we occupy in the context of the Universe? This work concerns mainly in providing accessible strategies to photograph the sky and how do we deal on didactic proposals Sky photographs using simple equipment. Our object of study was based on an analysis of the astronomy contents present in the regular high-school curriculum of the schools administered by the Paula Souza Center, linked to the National Curricular Parameters. This assessment was based on two points of view. In the first one the analysis was based on the astronomy contents present in the textbooks adopted by the schools for the triennium 2018/2019/2020, aligned with the National Curricular Parameters and the high school curriculum in the technical schools. The second point of view was through an online survey with the students of these schools, evaluating the percentage of these contents to which they actually had contact. In order to subsidize the analysis of these percentages, we performed a study on the Astronomy contents, in which five issues were listed, related to the proposal of topics addressed by the teachers of the disciplines that contains the theme Astronomy - \"History of Astronomy\"; \"Solar system\"; \"Climatic seasons\"; \"Sun-Earth-Moon System\" and \"Constellations of the Southern Hemisphere\". The results show that, despite the consistency between the National Curriculum Parameters and the high school curriculum analyzed, a significant percentage of students said they did not have contact with one or more subjects. The research served as a guideline for the need to elaborate and apply a didactic material composed of activities and workshops that, using Night Sky photography, experimentation and construction of didactic materials, acted as a catalyst for learning, reinforcing these contents, using many ways to approach the concepts contained in high school, encouraging students and even teachers to reflect on how we relate and learn about the Universe.
92

Planejamento de redes horizontais por simulações numéricas

Guzatto, Matheus Pereira January 2017 (has links)
Embora o tema planejamento de redes geodésicas seja largamente investigado, especialmente a partir da segunda metade da década de 70, no âmbito nacional, poucos estudos são encontrados relativos ao planejamento de redes geodésicas, especialmente por meio de simulações numéricas. Recentemente, KLEIN (2014) propôs um método para o planejamento de redes geodésicas (denominado aqui de Método Klein – MK), solucionado por meio de tentativa e erro. Dentro desse contexto objetivo deste trabalho é propor melhorias e adaptar o MK para redes horizontais por meio de simulações numéricas, algo que ainda não é encontrado na Literatura aplicado à otimização de redes. No referido método, cada vez que a rede é reprovada em algum dos critérios considerados, necessita-se de um incremento feito com base na expertise do usuário. Neste trabalho foi desenvolvido um programa (em código aberto) para tornar o método independente de decisões por parte do usuário com o objetivo de tornar o MK viável. Enquanto o geodesista testa decisões em um espaço limitado de opções (por tentativa e erro), a proposta desenvolvida nessa pesquisa testa à exaustão todas as possibilidades do problema por simulações numéricas. Para isso, o usuário deve informar, além dos parâmetros considerados no MK, as seguintes informações: as coordenadas dos pontos de controle (suas precisões e direção(ões) do(os) azimute(es)); as coordenadas aproximadas dos pontos desconhecidos; quais observações serão usadas inicialmente; possíveis novas observações e, por fim, os equipamentos disponíveis. Foram implementadas três estratégias visando minimizar o custo na etapa de planejamento, em ordem crescente de custo, são elas: repetição das observações originalmente propostas (E1); adição de novas visadas (E2) e troca de equipamento por outro de maior precisão (E3). O programa desenvolvido foi testado em três experimentos usando dados provenientes de uma rede real implantada no entorno do campus Florianópolis do Instituto Federal de Santa Catarina e simulando o uso de três equipamentos distintos. Os resultados obtidos mostram que as adaptações tornaram o MK viável do ponto de vista prático e os objetivos propostos foram concluídos com sucesso. Entre as conclusões obtidas deve-se citar: existe uma limitação para incerteza final da rede em função do equipamento utilizado; as visadas adicionais devem ser combinadas de forma a diminuir o número de estações entre os pontos de controle e os vértices desconhecidos da rede; a melhor maneira de aumentar consideravelmente o nível de confiabilidade de uma observação é repetindo-a. Por fim, são feitas considerações sobre as limitações do método proposto: dificuldade do usuário em encontrar valores ideais para a incerteza final da rede; interface visual pouco amigável; método limitado a redes horizontais; e ausência da variável custo de maneira quantitativa na etapa de planejamento. / Although the topic of geodetic network planning has been extensively investigated, especially since the second half of the 1970s, at the national level, few studies have been carried out regarding the planning of geodetic networks, especially through numerical simulations. Recently, KLEIN (2014) proposed a method for the planning of geodesic networks (here called Klein - MK Method), solved by trial and error. Within this context, the objective of this work is to propose improvements and to adapt the MK to horizontal networks through numerical simulations, something that is not yet found in Literature applied to network optimization. In Klein’s work, each time the network is disapproved in any of the considered criteria, an increment is necessary based on the user's expertise. In this work, a program (open source) was developed to make the method independent of user’s decisions with the objective of disseminating the Klein Method (MK) in the related community. While the geodesist tests decisions in a limited range of options (by trial and error), the proposal developed in this paper exhausts all possibilities of the problem by numerical simulations. For this, the user must inform, in addition to the parameters considered in the MK, the following information: coordinates control points (their precisions and direction (s) of the azimuth (s)); approximate coordinates of the unknown points; which observations will be used initially; new possible observations and, finally, the available equipments. Three strategies were implemented in order to minimize the cost of the designing step, in order of increasing cost, they are: repetition of the originally proposed observations (E1); Addition of new sights (E2) and exchange of equipment for another one of better precision (E3). The developed program was tested in three experiments using data from a real network implanted in the surroundings of Florianópolis campus of the Federal Institute of Santa Catarina and simulating the use of three different equipments. Satisfactory results were obtained and the proposed objectives were successfully completed. Among the conclusions obtained should be mentioned: there is a limitation for the final accuracy of the network according to the equipment used; additional sights must be combined in such a way to reduce the number of stations between control points and unknown vertices of the network; The best way to greatly increase the level of reliability of an observation is by repeating it. Finally, considerations are made about the limitations of the proposed method: the difficulty of the user to find ideal values for the final uncertainty of the network; Unfriendly visual interface; Method limited to horizontal networks and absence of quantitative cost analysis in the planning step.
93

Análise dinâmica não linear geométrica de estruturas e mecanismos reticulados planos com ligações deslizantes / Geometrical nonlinear dynamical analysis of plane frame structures and mechanisms with sliding joints

Siqueira, Tiago Morkis 26 February 2016 (has links)
Desenvolve-se uma formulação lagrangeana total do método dos elementos finitos para análise dinâmica de estruturas e mecanismos reticulados planos contendo ligações deslizantes sujeitas a grandes deslocamentos e rotações. Estas são introduzidas ao sistema mecânico na forma de juntas prismáticas e cilíndricas por meio do método dos multiplicadores de Lagrange, permitindo sua utilização na simulação de diversos tipos de estruturas e mecanismos. Também são consideradas rótulas entre as barras, estas introduzidas por meio da compatibilidade cinemática dos graus de liberdade dos nós comuns. A formulação do método dos elementos finitos adotada utiliza como parâmetros nodais as posições e os giros de modo desacoplado. Assim, pode-se utilizar a cinemática exata para barras de Reissner na análise de deslocamentos e giros finitos da estrutura. Adota-se o modelo constitutivo de Saint-Venant-Kirchhoff que relaciona a medida de deformação objetiva de Green-Lagrange com o tensor de tensões de Piola-Kirchhoff de segunda espécie. O equilíbrio dinâmico do sistema é obtido pelo princípio da energia total estacionária e a solução do sistema não linear de equações resultante é obtida pelo método de Newton-Raphson. A integração temporal é realizada pelo método de Newmark. São apresentados diversos exemplos para validação da formulação desenvolvida, os quais são comparados com soluções analíticas de modo a evidenciar as possibilidades de aplicação da formulação proposta. / A total lagrangian finite element method formulation is developed for the dynamic analysis of plane frame structures and mechanisms containing sliding joints that undergoes large displacements and rotations. Those connections are introduced in the mechanical system as prismatic and cylindrical joints by the method of Lagrange multipliers, allowing its use on the simulation of several types of structures and mechanisms. Hinges between bars are also considered by kinematic compatibility of the degrees of freedom on the common node. The adopted finite element formulation uses as nodal parameters uncoupled positions and angles. Therefore, Reissner exact kinematics for bars can be utilized for structural finite deformation. The Saint-Venant-Kirchhoff constitutive model, which relates the objective Green-Lagrange strain measure with the second Piola-Kirchhoff stress tensor, is adopted. The principle of stationary total energy is used to obtain the dynamic nonlinear equilibrium of the system and the solution of the resulting nonlinear system of equations is done by the Newton-Raphson method. The Newmark method is adopted for time integration. Several examples are presented for the validation of the developed formulation, and those are compared with analytical solutions in order to clarify the possibilities of application of the proposed formulation.
94

The Development of the Benign Paroxysmal Positional Vertigo Symptom Impact Questionnaire (BSIQ)

Akin, Faith, Smith, Sherri, Hall, Courtney D., Riska, Kristal M., Larkin, Annabelle 10 February 2019 (has links)
No description available.
95

The Development of the Benign Paroxysmal Positional Vertigo Symptom Impact Questionnaire (BSIQ)

Akin, Faith W., Smith, Sherri L., Hall, Courtney D., Riska, Kristal M., Larkin, Annabelle 26 February 2019 (has links)
No description available.
96

Automating Geographic Object-Based Image Analysis and Assessing the Methods Transferability : A Case Study Using High Resolution Geografiska SverigedataTM Orthophotos

Hast, Isak, Mehari, Asmelash January 2016 (has links)
Geographic object-based image analysis (GEOBIA) is an innovative image classification technique that treats spatial features in an image as objects, rather than as pixels; thus resembling closer to that of human perception of the geographic space. However, the process of a GEOBIA application allows for multiple interpretations. Particularly sensitive parts of the process include image segmentation and training data selection. The multiresolution segmentation algorithm (MSA) is commonly applied. The performance of segmentation depends primarily on the algorithms scale parameter, since scale controls the size of image objects produced. The fact that the scale parameter is unit less makes it a challenge to select a suitable one; thus, leaving the analyst to a method of trial and error. This can lead to a possible bias. Additionally, part from the segmentation, training area selection usually means that the data has to be manually collected. This is not only time consuming but also prone to subjectivity. In order to overcome these challenges, we tested a GEOBIA scheme that involved automatic methods of MSA scale parameterisation and training area selection which enabled us to more objectively classify images. Three study areas within Sweden were selected. The data used was high resolution Geografiska Sverigedata (GSD) orthophotos from the Swedish mapping agency, Lantmäteriet. We objectively found scale for each classification using a previously published technique embedded as a tool in eCognition software. Based on the orthophoto inputs, the tool calculated local variance and rate of change at different scales. These figures helped us to determine scale value for the MSA segmentation. Moreover, we developed in this study a novel method for automatic training area selection. The method is based on thresholded feature statistics layers computed from the orthophoto band derivatives. Thresholds were detected by Otsu’s single and multilevel algorithms. The layers were run through a filtering process which left only those fit for use in the classification process. We also tested the transferability of classification rule-sets for two of the study areas. This test helped us to investigate the degree to which automation can be realised. In this study we have made progress toward a more objective way of object-based image classification, realised by automating the scheme. Particularly noteworthy is the algorithm for automatic training area selection proposed, which compared to manual selection restricts human intervention to a minimum. Results of the classification show overall well delineated classes, in particular, the border between open area and forest contributed by the elevation data. On the other hand, there still persists some challenges regarding separating between deciduous and coniferous forest. Furthermore, although water was accurately classified in most instances, in one of the study areas, the water class showed contradictory results between its thematic and positional accuracy; hence stressing the importance of assessing the result based on more than the thematic accuracy. From the transferability test we noted the importance of considering the spatial/spectral characteristics of an area before transferring of rule-sets as these factors are a key to determine whether a transfer is possible.
97

Discovery and Extraction of Protein Sequence Motif Information that Transcends Protein Family Boundaries

Chen, Bernard 17 July 2009 (has links)
Protein sequence motifs are gathering more and more attention in the field of sequence analysis. The recurring patterns have the potential to determine the conformation, function and activities of the proteins. In our work, we obtained protein sequence motifs which are universally conserved across protein family boundaries. Therefore, unlike most popular motif discovering algorithms, our input dataset is extremely large. As a result, an efficient technique is essential. We use two granular computing models, Fuzzy Improved K-means (FIK) and Fuzzy Greedy K-means (FGK), in order to efficiently generate protein motif information. After that, we develop an efficient Super Granular SVM Feature Elimination model to further extract the motif information. During the motifs searching process, setting up a fixed window size in advance may simplify the computational complexity and increase the efficiency. However, due to the fixed size, our model may deliver a number of similar motifs simply shifted by some bases or including mismatches. We develop a new strategy named Positional Association Super-Rule to confront the problem of motifs generated from a fixed window size. It is a combination approach of the super-rule analysis and a novel Positional Association Rule algorithm. We use the super-rule concept to construct a Super-Rule-Tree (SRT) by a modified HHK clustering, which requires no parameter setup to identify the similarities and dissimilarities between the motifs. The positional association rule is created and applied to search similar motifs that are shifted some residues. By analyzing the motifs results generated by our approaches, we realize that these motifs are not only significant in sequence area, but also in secondary structure similarity and biochemical properties.
98

Physikalische und transkriptionelle Kartierung der mit dem Russell-Silver-Syndrom assoziierten Chromosomenregion 17q23-q24 / Physical and transcriptional mapping of the chromosomal region 17q23-q24 associated with Russell-Silver syndrome

Dörr, Sylvia 27 January 2000 (has links)
No description available.
99

DEVELOPMENT OF NOVEL AHR ANTAGONISTS

Lee, Hyosung 01 January 2010 (has links)
Aryl hydrocarbon receptor (AHR) is a sensor protein, activated by aromatic chemical species for transcriptionally regulating xenobiotic metabolizing enzymes. AHR is also known to be involved in a variety of pathogenesis such as cancer, diabetes mellitus, cirrhosis, asthma, etc. The AHR signaling induced by xenobiotics has been intensively studied whereas its physiological role in the absence of xenobiotics is poorly understood. Despite a number of ligands of AHR have been reported thus far, further applications are still hampered by the lack of specificity and/or the partially agonistic activity. Thus, a pure AHR antagonist is needed for deciphering the AHR cryptic as well as potential therapeutic agent. The Proteolysis Targeting Chimera (PROTAC) is a bi-functional small molecule containing a ligand and proteolysis inducer. PROTAC recruits the target protein to proteolysis machinery and elicits proteolysis. Thus far, a number of PROTAC have been prepared and demonstrated to effectively induce the degradation of targeted protein in cultured cells, validating PROTAC as a useful research tool. In the present study, PROTACs based on apigenin was prepared and demonstrated to induce the degradation of AHR, providing the proof of concept. To improve activity, a synthetic structure, CH-223191, was optimized for antagonistic activity by positional scanning identifying several AHR antagonists. PROTACs based on the optimal structure were prepared and assessed their biological activity. The products and synthetic scheme described hereby will be helpful for the further understanding on AHR biology as well as for developing therapeutic agents targeting AHR.
100

IMPACT OF MICROPHONE POSITIONAL ERRORS ON SPEECH INTELLIGIBILITY

Muthukumarasamy, Arulkumaran 01 January 2009 (has links)
The speech of a person speaking in a noisy environment can be enhanced through electronic beamforming using spatially distributed microphones. As this approach demands precise information about the microphone locations, its application is limited in places where microphones must be placed quickly or changed on a regular basis. Highly precise calibration or measurement process can be tedious and time consuming. In order to understand tolerable limits on the calibration process, the impact of microphone position error on the intelligibility is examined. Analytical expressions are derived by modeling the microphone position errors as a zero mean uniform distribution. Experiments and simulations were performed to show relationships between precision of the microphone location measurement and loss in intelligibility. A variety of microphone array configurations and distracting sources (other interfering speech and white noise) are considered. For speech near the threshold of intelligibility, the results show that microphone position errors with standard deviations less than 1.5cm can limit losses in intelligibility to within 10% of the maximum (perfect microphone placement) for all the microphone distributions examined. Of different array distributions experimented, the linear array tends to be more vulnerable whereas the non-uniform 3D array showed a robust performance to positional errors.

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