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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.
31

A circulação de saberes na formação continuada dos professores: uma análise do PEC-municípios na perspectiva dos estudos comparados em educação / The circulation of knowledge in the continuing education of teachers: an analysis of the PEC-cities in the perspective of comparative studies in education

Luciana Cristina Porfírio 21 June 2012 (has links)
O presente trabalho aborda a circulação de saberes em torno da profissionalização docente num programa de formação continuada de professores das séries iniciais, o PEC-Municípios, desenvolvido no Estado de São Paulo, por iniciativa da Secretaria de Estado da Educação, em parceria com algumas universidades, no período de 2006 a 2008. A pesquisa adotou as perspectivas teóricas mais recentes dos estudos comparados em educação, que podem ser classificados em duas tradições investigativas distintas: a primeira, representada por alguns autores vinculados à Universidade de Standford, dos quais se destacam Meyer e Ramírez, comumente citados nos trabalhos como neoinstitucionalistas; a segunda, modelarmente representada por Schriewer, por alguns, classificadas como tendência hermenêutica. Por meio do estudo do discurso e dos dispositivos didáticos presente no material produzido no âmbito do Programa para ser distribuído para os professores cursistas, foi possível identificar um conjunto de autores, textos e conceitos que têm circulado amplamente no contexto internacional das reformas educativas empreendidas desde os anos 1990. Foi notável na análise do material a presença das prescrições em torno da ideia de profissional reflexivo, que passa a ser o mote da reconstrução da identidade profissional docente nesse período, com ênfase nos saberes da prática e na apropriação das ideias centrais daquele conjunto de autores e textos que circulam internacionalmente. Nessa análise, os conceitos de externalização (Schriewer) e de estrangeiro indígena (Popkewitz) foram importantes ferramentas teóricas para compor um quadro analítico do discurso produzido no âmbito do PEC-Municípios. / The present paper discusses the circulation of knowledge about the professionalization of a program of continuous training of teachers in early grades, the PEC-cities, developed in the State of São Paulo, at the initiative of the Ministry of Education, in partnership with some universities in the period from 2006 to 2008. The research adopted the latest theoretical perspectives of comparative studies in education, which can be classified into two different investigative traditions: the first, represented by some authors linked to Stanford University, among which are Meyer and Ramirez, commonly mentioned in works like \"neo-institutionalists\", and the second is represented by modelarmente Schriewer by some tendency classified as hermeneutics. Through the study of speech and the devices in this didactic material produced under the program to be distributed to the participant teachers, it was possible to identify a set of authors, texts and concepts that have been circulating widely in the international context of educational reforms undertaken since 1990. In the present analysis of the material, it was noticed prescriptions around the idea of \"reflective practitioner\", which happens to be the theme of the reconstruction of professional identity of teachers in this period, with emphasis on the practical knowledge and ownership of the core ideas that set of authors and texts that circulate internationally. In this analysis, the concepts of externalization (Schriewer) and \"foreign native\" (Popkewitz) were important theoretical tools to compose an analytical framework of the discourse produced in the PEC-Cities.
32

Uso(s) das novas tecnologias em um programa de formação de professores: possibilidades, controle e apropriações / Use(s) of the new tecnologies in an education program for in-service teachers: possibilities, control and appropriations.

Andressa de Andrade 19 March 2007 (has links)
Este trabalho apresenta resultados de uma investigação acerca dos usos das mídias interativas utilizadas no PEC - Formação Universitária Municípios, um programa de formação de professores em serviço que encerrou suas atividades em dezembro de 2004. O programa faz parte das políticas educacionais que têm incentivado a adoção da Educação a Distância (EaD) e o uso das Novas Tecnologias de Informação e Comunicação (NTIC) na formação docente. A metodologia qualitativa utilizada na pesquisa envolveu atividades de observação in loco, entrevistas gravadas com alunas-professoras e profissionais do programa e coleta de documentos de tipo diverso -impressos, digitalizados e em vídeo. As análises basearam-se nos conceitos de uso, consumo, estratégias e táticas de Michel de Certeau (1994), de apropriação, de Roger Chartier (2001) e de técnica, de Piérre Lévy (1999). Os usos das NTICs constituem o foco do trabalho e são entendidos sob três aspectos: uso potencial, uso proposto e uso efetivado. Parte-se da hipótese de que na proposta de formação do programa predomina um modelo industrial de EaD, em que ensino e aprendizagem relacionam-se como uma forma especial de produção e consumo. Porém, esse uso não é necessariamente passivo. Considerando que as políticas atuais enfatizam o papel das novas mídias, como meio e como finalidade das ações de formação em serviço, o trabalho busca analisar criticamente os discursos que defendem o uso das novas tecnologias em educação como forma de inclusão de docentes e alunos na denominada Sociedade da Informação e aqueles que enfatizam a contribuição inédita da EaD pelo caráter de interação e interatividade. As análises empreendidas levaram a perceber várias ambigüidades na execução do programa, decorrentes, de um lado, das contradições internas a que esteve sujeito, dada a complexidade da proposta que envolveu várias instituições e instâncias de decisão; e, de outro, de sua proposta metodológica, de vez que assentada em uma concepção instrumental das mídias interativas. Ao lançar mão das novas tecnologias como meio de formação em massa, o PEC acabou por transformar suas potencialidades em obrigatoriedades, promovendo massificação, padronização e mecanização do ensino. Todavia, as alunas-professoras, na condição de consumidoras astuciosas, apropriaram-se das mídias de formas diversas daquelas previstas pelo programa, adequando o uso das mesmas a suas próprias necessidades. Tais apropriações, como parte integrante e positiva de um processo de autoformação, não foram levadas em conta pelo programa, a despeito de sua proposta pedagógica colocar ênfase e adotar como um de seus princípios o valor da experiência prática dos docentes. / This work presents the results of an investigation concerning the uses of interactive media utilized in the PEC - Formação Universitária Municípios, a high education program for inservice primary teachers, which ended its activities in December 2004. The program is part of the current public policies in education that have encouraged the implementation of distance education methodology and the use of the Information and Communication Technologies (ICT) in teacher education. A qualitative approach was taken, consisted of in loco observation, recorded interviews with the student-teachers and professionals who worked for the program, and gathering of printed, digitalized and recorded documents. The analyses are based on the concepts of use, consumption, strategies and tactics by Michel Certeau (1994), of appropriation by Roger Chartier (2001) and of technique by Piérre Lévy (1999). The focus of the study is the use of the ICT, with regard to three aspects: their potential use, their intended use and their actual use. The work starts with the assumption that the industrial distance education model is the core of the program and consider that, in such model, the teaching and learning relate to each other in a productive consumptive (not necessarily passive) manner. It was taking into account that the current public policies emphasize the role of the new media and technologies as a means as well as an end of the in-service education. With that in mind, the work aims at making a critical analysis of both the discourse of those who support the use of ICT in education as a means of inclusion of teachers and pupils in the so called Society of Information and of those who underline the brand new contribution of distance education based on its interaction and interactivity characteristics. The analyses mad explicit the various ambiguities of the program due, in part, to the complexity of its proposal that involved different institutions and levels of decisions, and also to the employed methodology based on an instrumentalist concept of the interactive media. Making use of the technologies as a means of mass education, the PEC ended to transforming the potential uses of the new technologies in mandatory ones, which resulted in mass use, standardization and mechanization of the education. Nevertheless, the student-teachers, as clever consumers, appropriated of the media in ways that were not anticipated by the program, tailoring them to their own necessities. In spite of having as pedagogical principle the value of the practical experiences, such appropriations were not appreciated by the program as being an essential part of the teacher?s self-education.
33

Políticas públicas educacionais para universalização da alfabetização com ênfase na penitenciária de Cascavel / Public educational policies for universalization of literacy with emphasis on the Cascavel penitentiary

Rogowski, Delir Freitas 21 September 2017 (has links)
Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2018-02-16T18:45:00Z No. of bitstreams: 2 Delir_Rogowski2017.pdf: 3564114 bytes, checksum: 4257b1cf67d9327ca894a517770d6a7f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-16T18:45:00Z (GMT). No. of bitstreams: 2 Delir_Rogowski2017.pdf: 3564114 bytes, checksum: 4257b1cf67d9327ca894a517770d6a7f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-09-21 / The dissertation investigates the development of educational public policies for the universalization of literacy in Paraná, the population in the context of deprivation of liberty by the EJA and government program, according to the Federal Constitution / 1988, the Law of Directives and Bases of Education - Law 9394/1996, with the objective of unveiling them. The methodology of the descriptive and documental research includes analysis of the legislation on the quality of the criminal treatment, including consultation in the SPR in search of the profile and school data of the prisoners in the State Penitentiary of Cascavel / PR. The theoretical reference is constituted by conceptual and contemporary approaches to public educational and criminal policies, based on the study, in addition to the aforementioned legislation, Law 10.172 / 2001, the Ibero- American Plan and the Internet, including official websites. The EJA, at the beginning of the 21st century, emerges as a policy of basic education implemented and brings important transformations with respect to the diversity and specificities of the subjects. In 1990 at the World Conference on Education for All in Jomtien, Thailand, valuable progress was made in discussing and creating the basic documents for eradicating illiteracy. In Latin America, in 1st place is Brazil, with 14 million and 815 thousand (IBGE-2000). In 2003, it created the Literate Brazil Program with a target of 50% reduction in the regions with the largest public target and by adhesion in the state , the so-called Parana Alfabetizado, with ⅓ of the investment by the Union. The commitment of the Ibero-American Plan, coordinated by the Organization of Ibero-American States xi (OEI), after studies in 2006, indicated actions as a solution to the countries, and to Brazil: during 9 years, investment of 3% of the MEC budget, but only applied 1%. Legal frameworks for prison education were strengthened through cooperation and governmental partnership between MEC / MJ and Paraná, between SEED / SEJU, to the universalization of literacy, culminating in the creation of specific CEEBJA / APED in the context of deprivation of liberty and selection of Public Server by public notice. The creation of CEQP / DEPEN-PR in 2012, with identified demand of 799 illiterate prisoners in the screening, (re) defined actions and methodologies to expand Educational Assistance, listing illiteracy, as a priority among the challenges to be faced. Thus, the government program is implemented in 2013 to enroll, by security measure, that prisoner unable to attend class daily, collaborating with the reduction to 77 illiterates in 2014 and proposal to overcome illiteracy in 2016. In the PEC, from the beginning of the the highest index was in 2011 with 5.05% and in 2014 with 0%. In the operational milestones, the SEJA-DEB / SEED Pedagogical Technician conceives the name of the Monitor / Alphabet, selected by specific edict, with criteria established to the function, to teach up to 05 Literate (illiterate) in the cell. In conclusion, in the state of Paraná, two forms of insertion of the illiterate to the universalization of literacy were developed: by the EJA (formal education) and by the PPA as a result of the consensus elaborated in the national and international scope. The need to increase the supply of prison education by the EJA is clear, with more investments including construction of classrooms in the penal units. / A dissertação investiga o desenvolvimento de políticas públicas educacionais para a universalização da alfabetização no Paraná, à população no contexto da privação de liberdade pela EJA e programa de governo, segundo a Constituição Federal/1988, a Lei de Execução Penal – Lei 7.210/1984, a Lei de Diretrizes e Bases da Educação – Lei 9394/1996, com objetivo de desvendá-las. A metodologia da pesquisa descritiva e documental inclui análise da legislação na qualidade do tratamento penal, inclusive consulta no SPR em busca do perfil e dados escolares dos presos na PEC–Penitenciária Estadual de Cascavel/PR. O referencial teórico constitui-se por abordagens conceituais e contemporâneas de políticas públicas educacionais e penais, a partir do estudo além da legislação já citada, da Lei 10.172/2001, do Plano Ibero-Americano e na internet, inclusive em sites oficiais. A EJA, no início do século XXI, emerge como política da educação básica implementada e traz importantes transformações com respeito a diversidade e especificidades dos sujeitos. Em 1990, na Conferência Mundial de Educação para Todos, em Jomtien -Tailândia, alcançou-se valioso progresso de discussão e criação dos documentos básicos para erradicação do analfabetismo. Na América Latina, em 1º lugar está o Brasil, com 14 milhões e 815 mil (IBGE-2000), cria em 2003, o Programa Brasil Alfabetizado com meta de 50% de redução nas regiões com maior público alvo e por adesão, no estado, o denominado Paraná Alfabetizado, com ⅓ do investimento pela União. O compromisso do Plano Ibero-Americano, coordenado pela Organização dos ix Estados Ibero-Americanos (OEI), após estudos em 2006, indicou ações como solução aos países, e ao Brasil: durante 9 anos, investimento de 3% do orçamento do MEC, porém aplicou-se somente 1%. Os marcos legais à educação prisional se fortaleceram a partir da cooperação e parceria governamental entre MEC/MJ e no Paraná, entre SEED/SEJU, à universalização da alfabetização, culminou na criação dos CEEBJA/APED específicos ao contexto da privação de liberdade e seleção de Servidor Público por edital. A criação da CEQP/DEPEN-PR em 2012, com demanda identificada de 799 presos analfabetos na triagem, (re) definiu ações e metodologias para ampliação da Assistência Educacional, elencando o analfabetismo, como prioridade entre os desafios a enfrentar. Assim, o programa de governo é implantado em 2013 para matrícula, por medida de segurança, daquele preso impossibilitado de frequentar aula diariamente, colaborando com a redução para 77 analfabetos em 2014 e proposta de superação do analfabetismo em 2016. Na PEC, do início da pesquisa, o maior índice foi em 2011 com 5,05% e em 2014 com 0%. Nos marcos operacionais, o Técnico Pedagógico SEJA-DEB/SEED concebe o nome do Monitor/Alfabetizador, selecionado por edital específico, com critérios estabelecidos à função, para ensinar até 05 Alfabetizandos (analfabeto), na cela. Em conclusão, no estado do Paraná, foram desenvolvidas duas formas de inserção do analfabeto à universalização da alfabetização: pela EJA (educação formal) e pelo PPA como resultado do consenso elaborado no âmbito nacional e internacional. É notória, a necessidade de ampliar oferta à educação prisional pela EJA, com mais investimentos inclusive para construção de salas de aula nas unidades penais.
34

Ensino “Além Mar” : trajetórias e travessias de estudantes africanos no ensino superior em Juiz de Fora - MG

Laier, Aline Cristina 10 March 2014 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-06-18T12:24:38Z No. of bitstreams: 1 alinecristinalaier.pdf: 2654107 bytes, checksum: 70d41f793d23b069a88714a3b7724649 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-06-27T12:13:25Z (GMT) No. of bitstreams: 1 alinecristinalaier.pdf: 2654107 bytes, checksum: 70d41f793d23b069a88714a3b7724649 (MD5) / Made available in DSpace on 2018-06-27T12:13:26Z (GMT). No. of bitstreams: 1 alinecristinalaier.pdf: 2654107 bytes, checksum: 70d41f793d23b069a88714a3b7724649 (MD5) Previous issue date: 2014-03-10 / A presente pesquisa tem por objetivo apreender as trajetórias e travessias dos estudantes africanos que migram para a cidade de Juiz de Fora para cursarem o ensino superior, notadamente os estudantes atrelados ao Programa estudante convênio graduação – PEC-G. Partindo do pressuposto de que a migração estudantil, para além do deslocamento espacial, traz em seu cerne transformações acerca das identidades dos indivíduos e se realiza por intermédio das redes sociais estabelecidas entre o país de origem e o país de destino, busca-se refletir como estudantes africanos se inserem no seio do universo estudantil da sociedade brasileira e de que forma a interação dentro desta nova realidade social contribui para que indivíduos e os grupos por eles formados acionem novas categorias identitárias, operando transformações no plano individual e social. “Ser africano” no contexto da vivência da sociabilidade de uma juventude universitária, é uma faceta identitária que se (re)afirma cotidianamente. Esta faceta também é celebrada através de eventos organizados por estes estudantes; através dos discursos do que é ser africano no contexto migratório, forma pela qual alguns elementos simbólicos são acionados. Também se pretende refletir acerca do projeto da migração estudantil, da decisão de migrar para cursar o ensino superior, a chegada e as experiências vivenciadas, assim como os planos para depois da formação. Como método, utilizou-se a etnografia, através da observação participante e de entrevistas abertas. E para um entendimento maior do universo social do qual estes estudantes são oriundos e sobre as origens e implicações das migrações estudantis, fez-se necessário uma pesquisa acerca da história das relações Brasil-África; sobre a (re)configuração de uma identidade negra à partir do século XX; a questão dos PALOP e a língua portuguesa como um patrimônio cultural em comum; assim como os acordos governamentais empreendidos pelo governo brasileiro e os países africanos de modo a fomentar as migrações / The current research aims at gathering the path and crossings of African students migrating to the city of Juiz de Fora to take a college degree, notoriously students related to the ProgramaEstudanteConvênioGraduação – PEC-G. Assuming that student migration, beyond spatial displacement, brings in its core shifts regarding individual identity and carries itself out through social networking established between home country and destination country, we aim to think over on how African students settle at the bosom of schooling universe of the Brazilian society and in what ways the interaction amongst this new social reality contributes for individuals and groups formed by them to activate new identity categories, operating changes individually and socially-wise. “Being African” in the context of sociability living of a college youth, is an identity facet reassured daily. This facet is also celebrated through events which are organized by those students; through speeches of what is being African in the migration setting, a way by which some symbolic elements are triggered. We also intend to reflect on the project of student migration, the choice of migration to take a college degree, the arrival and experiences lived, as much as plans after graduation. For a method, ethnography was used, through the observation of participants and open interviews. Also, for a better understanding of those students’ original student universe and about the origins and implications of student migration, a research about the Brazilian-African relation was necessary; about the (re)setting of a black identity at the 20th century; the question of Portuguese-speaking African countries and Portuguese language as a common cultural inheritance; as well as governmental agreements moved by the Brazilian government and African countries in order to encourage migrations.
35

Převedení výroby litiny z kuplovny na indukční pec / Change in production of cast iron

Sedláková, Jitka January 2010 (has links)
The subject of this work is to validate the possibility of managing the cast iron strength through residual Mg content and to determine methodically whether it is possible to exploit this technology in a foundry. It is another subject to determine the economics of the exchange of cupola furnace for electric induction furnace and methodically assess the possibilities of melting in the electric induction furnace.
36

Gas-loading apparatus for large-volume high-pressure cell

Bocian, Artur January 2012 (has links)
The Paris-Edinburgh cell (PEC) is a widely used opposed-anvil device for neutron scattering. Since its development, it has been used to study a number of samples loaded as solids or liquids. However, studying gases at room temperature has not yet been possible. Up until now only a few gases could be loaded as liquids, in cryogenic conditions. Thus, it was impossible to study many gases and gas mixtures and also it was difficult to use gases as pressure-transmitting media (PTM). In order to overcome these limitations, a technique that would enable loading of gases into the PEC was required. The work described in this thesis was focused on the design and use of a gas-loading system for the PEC. The challenge of designing such a system comes from the fact that the gases need to be loaded into the gasket at sufficient density in order to achieve any significant pressure during further compression in the cell. This can be achieved by using a separate pressure vessel. Because the whole PEC is too large to be placed inside the vessel, a technique of loading gas into the anvils separated from the rest of the cell had to be devised. Designing the holder for the anvils, which would make this possible, presented a major challenge as it should allow the anvils to be transferred between the vessel and the PEC, with the gasket filled with high-pressure gas. Then it needs to allow further compression of the gasket inside the PEC. The developed system consists of a pressure vessel and a locking clamp for the anvils. The pressure vessel is a closed-end thick-walled cylinder with a top cover which has an opening for a piston. The vessel is placed on the table of a hydraulic press and the piston, sealed by a high-pressure reciprocating seal, is used to transmit the force from hydraulic ram onto the anvils which are held by the clamp and placed inside the vessel. One of the anvils is fixed to the clamp and the other one is supported by spring-loaded latches - the latches engage when the anvils are pushed towards each other. Thus, when the force is applied onto the anvils to compress the gasket, latches lock the anvils in their positions stopping them from retracting and maintaining the gasket compressed after the force is released. The clamp allows the gasket to be filled with the gas and then deformed to seal the compressed gas. The locking mechanism keeps the gasket compressed, which enables the clamp to be transferred from the vessel to the PEC. After the system was built and tested, it was installed at ISIS neutron source (Oxfordshire, UK), where it has been used in several experiments. The first experiment prepared with the gas-loading system was a neutron diffraction study of nitrogen at high pressure. Nitrogen was chosen as a sample material because its high-pressure structural phase diagram is well established. Nitrogen was loaded into the gasket using the gas loader and then it was compressed in increments to 6 GPa in the PEC. β and δ phases of solid nitrogen were clearly seen in the collected neutron diffraction data. The experiment proved the usability of the gas-loading system and verified its expected performance. The second experiment utilizing the gas-loading system was to study singlecrystal and powder samples of sodium chloride (NaCl) and squaric acid (H2C4O4). For these studies argon was used as a PTM, replacing the conventionally used methanol-ethanol mixture (ME). Up until this experiment the highest pressure reported in single-crystal neutron-scattering experiments was 12 GPa. This limit was set by the solidi cation pressure of ME. With argon as the PTM, the samples were compressed to 15 GPa without any damage to the crystals. Another advantage of replacing ME with argon is improved hydrostaticity. The highest pressure that ME remain hydrostatic to is 11 GPa. Compressing beyond this point causes sheer stress acting on the sample which affects the quality of the neutron scattering data manifested in the appearance of peak-broadening in the diffraction patterns. With use of argon, the powder samples have been compressed to 18 GPa while maintaining quasi-hydrostatic pressure conditions, resulting in clean and sharp diffraction patterns without any noticeable peak-broadening.
37

The influence of sleep on memory

Mograss, Melodee A. January 2007 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.
38

Stored-grain Monitoring Utilizing Radio Wave Imaging

Asefi, Mohammad 20 June 2016 (has links)
Storage of large amounts of grain post-harvest is common during drying, distribution and preservation of crops. During storage, where grain is usually held in a large metallic container or bin, changes in temperature, moisture, and insect infestation can cause grain to spoil annual post-harvest crop losses are estimated up to 30% in some countries while Canadian losses of 2% exceed a billion dollars. Currently, locally-sensitive temperature and moisture sensors are a common way to monitor grain bins. Sensors are generally strung on heavy duty cables that can withstand the forces generated when unloading grain. This monitoring method provides a coarse sampling of the storage environment due to system cost and the fact that using many sensor cables would require significantly reinforcing the bin. Further, these cables are not suitable for monitoring stored crops that are dried by a combination of stirring and aeration. Over the past four years, I have developed multiple electromagnetic imaging based grain-monitoring systems with the goals of overcoming the deficiencies of existing sensor technology and allowing farmers and distributors a robust way to preserve our food stores and increase revenue. The proposed technology aims to produce global, quantitative images of grain properties throughout the bin from measurements taken by a few side-mounted antennas used to interrogate the bin contents. To develop this technology intensive research was put into the design of low profile, robust antennas as well as numerical analysis of the effects of different field distributions within conducting boundaries. Both electric and magnetic field sensitive antennas were built and tested in small lab-scale as well as full-scale grain bins to experimentally evaluate the performance of such imaging system. This thesis provides details on different system designs and analysis and describes the advantages and challenges associated with the techniques described. / October 2016
39

Ductile steel plate shear walls with PEC columns

Dastfan, Mehdi 11 1900 (has links)
The behavior of steel plate shear walls under the effects of lateral loads depends on the stiffness of the surrounding frame members. Previous research has quantified the minimum required stiffness of columns in the middle stories of steel plate shear wall systems. As the columns of the steel plate shear wall system are subjected to both large axial forces and bending moments, use of composite columns is a viable option in this system. Among the different types of composite columns, the recently developed partially encased composite columns with built-up steel sections have some advantages over other types of composite columns and thus their performance as columns in steel plate shear wall systems needs to be studied. In the first part of this research, a numerical and analytical study has developed a new design parameter and determined the minimum required stiffness of end beams in end panels of the steel plate shear wall system. The effect of the rigidity of the frame connections on the uniformity of the tension field has also been studied in this part. The second part of this research includes two large scale tests on steel plate shear walls with built-up partially encased composite (PEC) columns. One of the test specimens was modular and the other one used reduced beam sections in the frame. The results of the tests show that the columns were stiff enough to anchor the infill plate. The PEC columns in these tests performed in a ductile manner. The overall system behavior was ductile, stable and the specimens showed good seismic behavior and redundancy. Based on the results and observations of this research, design recommendations for PEC columns used as the vertical boundary members of steel plate shear walls are provided. / Structural Engineering
40

Improving secondary structure prediction with covariation analysis and structure-based alignment system of RNA sequences

Shang, Lei, active 2013 10 February 2014 (has links)
RNA molecules form complex higher-order structures which are essential to perform their biological activities. The accurate prediction of an RNA secondary structure and other higher-order structural constraints will significantly enhance the understanding of RNA molecules and help interpret their functions. Covariation analysis is the predominant computational method to accurately predict the base pairs in the secondary structure of RNAs. I developed a novel and powerful covariation method, Phylogenetic Events Count (PEC) method, to determine the positional covariation. The application of the PEC method onto a bacterial 16S rRNA sequence alignment proves that it is more sensitive and accurate than other mutual information based method in the identification of base-pairs and other structural constraints of the RNA structure. The analysis also discoveries a new type of structural constraint – neighbor effect, between sets of nucleotides that are in proximity in the three dimensional RNA structure with weaker but significant covariation with one another. Utilizing these covariation methods, a proposed secondary structure model of an entire HIV-1 genome RNA is evaluated. The results reveal that vast majority of the predicted base pairs in the proposed HIV-1 secondary structure model do not have covariation, thus lack the support from comparative analysis. Generating the most accurate multiple sequence alignment is fundamental and essential of performing high-quality comparative analysis. The rapid determination of nucleic acid sequences dramatically increases the number of available sequences. Thus developing the accurate and rapid alignment program for these RNA sequences has become a vital and challenging task to decipher the maximum amount of information from the data. A template-based RNA sequence alignment system, CRWAlign-2, is developed to accurately align new sequences to an existing reference sequence alignment based on primary and secondary structural similarity. A comparison of CRWAlign-2 with eight alternative widely-used alignment programs reveals that CRWAlign-2 outperforms other programs in aligning new sequences with higher accuracy. In addition to aligning sequences accurately, CRWAlign-2 also creates secondary structure models for each sequence to be aligned, which provides very useful information for the comparative analysis of RNA sequences and structures. The CRWAlign-2 program also provides opportunities for multiple areas including the identification of chimeric 16S rRNA sequences generated in microbiome sequencing projects. / text

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