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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.
1

Evaluation of USDA feeder calf grades and health status of steers and their impact on live and carcass performance in south Texas

Groschke, David Wayne 01 November 2005 (has links)
In 2003-2004, the Texas A&M University Ranch to Rail South program evaluated 430 steers in Edroy, TX. Data were analyzed on several traits, but feeder calf frame and muscle grades and health status were emphasized. Muscle thickness grade (M), frame size grade (F), muscle thickness by frame size interaction (M*F), sire breed type classification (SIRECODE), lung score (LUNG), ranch of origin (RANCH), and level of treatment (LVLTRT) were evaluated as independent variables as affecting ribeye area (REA), marbling score (MARB), fat thickness (FAT), hot carcass weight (HCW), average daily gain (ADG), medicine costs (MED), days on feed (DOF), initial value (VALUE), carcass value (CARVAL), and initial weight (INWT). M (P < .0001), F (P < .0001), M*F (P < .0001), SIRECODE (P < .0001), RANCH (P < .0001), LVLTRT (P = .0016), and INWT (P < .0001) were all significant influences on initial value upon arrival. SIRECODE (P = .0344), RANCH (P = .0571), and INWT (P < .0001) were significant in impacting carcass value. RANCH (P = .0045) and INWT (P < .0001) were very significant influences upon ribeye area when the steers were harvested. RANCH (P < .0001) was also influential on marbling score, and LVLTRT (P = .1096) was slightly significant for MARB. M (P = .0659), F (P = .0721), and M*F (P = .0722) were moderately significant in influencing fat thickness. However, SIRECODE (P = .0148) and RANCH (P < .0001) were significant in impacting FAT. HCW was significantly affected by SIRECODE (P = .0056), RANCH (P < .0001), and INWT (P < .0001). For live performance, SIRECODE (P = .0120) and RANCH (P < .0001) were significant influences upon average daily gain. SIRECODE (P < .0001), RANCH (P < .0001), LVLTRT (P < .0001), and INWT (P < .0001) were significant influences on days on feed for the steers. Finally, RANCH (P < .0001) and LVLTRT (P < .0001) were significant in affecting medicine costs. These findings suggest ranch of origin and breed type play major roles in affecting live and carcass performance.
2

Gestão da QOS em arquiteturas de grades computacionais orientadas a serviços

Cedro, Daniela Medeiros 08 1900 (has links)
CEDRO, D. M. Gestão da QOS em arquiteturas de grades computacionais orientadas a serviços. 2010. 72 f. Dissertação (Mestrado em Engenharia de Teleinformática) - Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2010. / Submitted by Marlene Sousa (mmarlene@ufc.br) on 2012-04-26T19:22:09Z No. of bitstreams: 1 2010_dis_dmcedro.pdf: 1683786 bytes, checksum: ad1aa16b7584d623bbff6ed9867f1845 (MD5) / Approved for entry into archive by Marlene Sousa(mmarlene@ufc.br) on 2012-04-26T19:23:16Z (GMT) No. of bitstreams: 1 2010_dis_dmcedro.pdf: 1683786 bytes, checksum: ad1aa16b7584d623bbff6ed9867f1845 (MD5) / Made available in DSpace on 2012-04-26T19:23:17Z (GMT). No. of bitstreams: 1 2010_dis_dmcedro.pdf: 1683786 bytes, checksum: ad1aa16b7584d623bbff6ed9867f1845 (MD5) Previous issue date: 2010-08 / The increasing deployment of services on the Internet is augmenting the demand for processing resources on the server side encouraging the use of Clusters of Computers and Grid Computing. At the same time, the engineering software brings new paradigms such as Service Orientation, which impose new challenges to be addressed by service providers. The convergence of these factors led Architectures for Service Oriented Grid Computing. This work presents an architecture proposed for service oriented grid computing, called G-DSAC (Grid - DiffServ Admission Control), which deals with aspects related to QoS (Quality of Service) and service differentiation. The G-DSAC architecture is an extension of WS-DSAC architecture (Web Servers - AdmissionControl DiffServ). This extension includes design of a Service Oriented Grid Computing Architecture which is able to ensure SLAs (Service Level Agreements) established with consumers using effectively the resources available in the grid. The solution also provides service differentiation in relation to response times offered to customers, end users and service consumers. The proposed new architecture introduces a block of functionality in a service oriented grid computing platform composited by Multclusters. This block allows publishing and localization of services, authentication and classification of requests and scheduling of those within the grid according to the service class they belong. It was also implemented a prototype that allowed the realization of experiments in a testing platform to evaluate the solution's ability to achieve the objectives proposed by the new architecture. / A crescente disponibilização de serviços através da Internet vem impondo uma demanda cada vez maior por recursos de processamento no lado servidor favorecendo a utilização dos Clusters de Computadores e das Grades Computacionais. Em paralelo, a engenharia de software traz novos paradigmas, como a Orientação a Serviços, que impõem novos desafios a serem tratados pelos fornecedores de serviços. A convergência destes fatores deu origem às Arquiteturas de Grades Computacionais Orientadas a Serviços. Neste trabalho é apresentada uma proposta de arquitetura em grades computacionais orientada a serviços, denominada G-DSAC (Grid – DiffServ Admission Control), que trata de aspectos ligados à QoS (Quality of Service) e a diferenciação de serviços. A arquitetura G-DSAC é uma extensão da arquitetura WS-DSAC (Web Servers – DiffServ AdmissionControl). Esta extensão compreende a concepção de uma solução voltada para grades computacionais que é capaz de garantir os SLAs (Service Level Agreements) estabelecidos com os consumidores de serviços utilizando de forma otimizada os recursos de processamento disponibilizados na grade. A solução permite ainda a diferenciação de serviços no que diz respeito aos tempos de resposta oferecidos aos clientes, usuários finais e serviços consumidores. A nova arquitetura proposta introduz um bloco de funcionalidades em uma plataforma de grade computacional orientada a serviços formada por multclusters. Esse bloco permite a publicação e localização de serviços, autenticação e classificação de requisições e o escalonamento das mesmas dentro da grade de acordo com a classe de serviço a qual pertencem. Foi também implementado um protótipo que permitiu a realização de experimentos em uma plataforma real de testes visando avaliar a capacidade da solução em atingir os objetivos por ela propostos.
3

Grades dieletricas anisotropicas

Silva, Nildsen Fernando Lisboa da 16 April 1999 (has links)
Orientador: Attilio Jose Giarola / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-07-25T06:42:08Z (GMT). No. of bitstreams: 1 Silva_NildsenFernandoLisboada_M.pdf: 2044790 bytes, checksum: 0aadc23825dcd8d3900a89173ed7b05b (MD5) Previous issue date: 1999 / Resumo: A análise de grades dielétricas anisotrópicas foi feita considerando-se uma anisotropia do tipo uniaxial. Procurou-se estudar as características dicróicas, na faixa de freqüências milimétricas, das grades dielétricas anisotrópicas utilizando a teoria Modal Rigorosa. Os resultados numéricos são apresentados em função da variação das constantes dielétricas do tipo senoidal e do tipo degrau, assim como, para polarizações da onda incidente dos tipos TE e TM. O efeito da anisotropia é estudado variando-se o quadrado da razão de anisotropia do material uniaxialmente anisotrópico. Os resultados numéricos mostram como esta variação afeta o perfil ressonante destas grades e quais as vantagens em se usar a anisotropia em grades dielétricas utilizadas como filtros / Abstract: The analysis of anisotropic dielectric gratings was done by considering an uniaxial anisotropy. The dichroic characteristics were studied in the millimeter wave band of anisotropic dielectric gratings using a Rigorous Modal Theory. The numerical results are presented as functions of parameters of sinosoidally and step varying dielectric constants, as well as of wave polarizations of TE or TM type. The anisotropy effect is studied by varying the square of the anisotropy ratio of the material. The numerical results show how this variation affects the resonant profile of these gratings and the advantages ofusing anisotropic dielectric gratings in filters / Mestrado / Mestre em Engenharia Elétrica
4

A Description Of A Gifted Program In A Rural Mississippi County School District Through The Perceptions Of Its Student Participants

Dumas, Theresa Young 15 December 2007 (has links)
The purpose of this study was to describe a gifted program in a rural Mississippi county school district through the perceptions of its student participants. This study consisted of a total of 19 participants. Thirteen participants in this study were students in grades 7-8 who were currently enrolled in the gifted program and six participants were students in grades 11-12 who had previously been enrolled in the gifted program. The researcher interviewed each focus group on two separate occasions using a tape recorder to record the participants’ responses. Each focus group interview lasted about one hour. This study used qualitative research. Fraenkel & Wallen (2003) stated that “Qualitative researchers have a much greater flexibility in both strategies and techniques they use and the overall research process itself. Their designs tend to emerge during the course of the research” (p.16). Data in this study were collected using an Interview Protocol created by the researcher. The Interview Protocol was comprised of background information, topics regarding the gifted program, and topics regarding students’ perspectives. After transcribing the data, the researcher developed a matrix to determine the themes/patterns found in the study. Results suggested that most students entered the gifted program in the second grade by teacher recommendation and taking an IQ test. Results suggested that the perspectives of students who were presently participating in the gifted program, or who had previously participated in the gifted program, were positive in respect to the gifted program. Furthermore, results suggested that the rigorous content of the gifted program prepared 7 - 8 grade participants for the course content taught in their regular education classes and for entrance into high school. This study also suggested that students in the 11- 12 grades were better prepared for the course content taught in their regular education classes and the Advanced Placement classes offered in their school. Results from interviews indicated that some participants’ self-esteem rose due to being in the gifted program. Results also indicated that the participants felt a need to overachieve as a gifted student. It is recommended that a longitudinal study be conducted with a follow-up of gifted program graduates.
5

Um modelo de diagnóstico distribuído e hierárquico para tolerância a ataques de manipulação de resultados em grades computacionais / A model of diagnosis distributed hierarchical and tolerance to the attacks of manipulation of results in computational grids

Martins, Felipe Sampaio 08 August 2006 (has links)
MARTINS, F. S. Um modelo de diagnóstico distribuído e hierárquico para tolerância a ataques de manipulação de resultados em grades computacionais. 2006. 95 f. Dissertação (Mestrado em Engenharia de Teleinformática) – Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2006. / Submitted by Marlene Sousa (mmarlene@ufc.br) on 2016-04-04T14:27:55Z No. of bitstreams: 1 2006_dis_fsmartins.pdf: 22736379 bytes, checksum: 3da7a67368d4aa866f5518b6203a556c (MD5) / Approved for entry into archive by Marlene Sousa(mmarlene@ufc.br) on 2016-04-06T17:45:30Z (GMT) No. of bitstreams: 1 2006_dis_fsmartins.pdf: 22736379 bytes, checksum: 3da7a67368d4aa866f5518b6203a556c (MD5) / Made available in DSpace on 2016-04-06T17:45:30Z (GMT). No. of bitstreams: 1 2006_dis_fsmartins.pdf: 22736379 bytes, checksum: 3da7a67368d4aa866f5518b6203a556c (MD5) Previous issue date: 2006-08-08 / Information security in grid computing involves requirements that go beyond the traditional networks. Concerning specifically Integrity, most of existing solutions deal with it only during data transmission, ensuring non-violation of data in the communication between machines. Nevertheless, it is also necessary to guarantee data integrity during its processing, so that jobs results must not suffering any improper handling. Otherwise, the results manipulation compromises the application as a whole, also causing a high processing overhead. In order to avoid that grid users obtain uncorrected results due to malicious elements, this work proposes a diagnosis model for tolerating security faults in largescale computational grids, considering the integrity verification during job processing. In this way, it is possible to exclude those misbehaving processing units (nodes) interested in damaging the execution of processes, providing thus a high performance computing environment only formed by reliable nodes. The usage of system-level diagnosis as a strategy against jobs results manipulation attacks reveals itself an efficient solution, since it does not depend on the hardware platform and it is interoperable with security local solutions. This feature allows the employment of the proposed model at the majority of grid computing middlewares. Furthermore, the proposed diagnosis model organizes the nodes into logical clusters, establishing a hierarchy among them, in accordance to the role of each node (executor, tester or ultra-reliable), assigned through its historical behavior in the environment. This approach enables diagnosis to be made in a distributed way with the participation of nodes that provide an expected degree of confidence. To validate this strategy, a new security layer was implemented in a grid simulator in order to introduce the assertions and the behaviors described in the proposed model. The results testify the effectiveness of the model at scenarios with different quotas of malicious nodes, providing a rate of detection of 100% and accuracy of 99,7% of processed jobs, with 12,3% of overhead. / A segurança da informação em grades computacionais envolve requisitos que vão além dos estabelecidos para as redes convencionais. Tratando-se especificamente de Integridade, a maioria das soluções existentes resolve essa questão apenas no escopo de transmissão, garantindo a nao-violação dos dados durante a comunicação entre as maquinas. Todavia, e preciso também garantir a integridade dos dados durante o seu processamento, de modo que os resultados das tarefas (jobs) processados em uma grade não sofram qualquer alteração indevida. De outra forma, a manipulação de resultados compromete a aplicação como um todo, incidindo num alto custo em termos de desempenho. Para evitar que usuários obtenham resultados incorretos em virtude de elementos maliciosos, esta dissertação propõe um modelo de diagnostico para tolerância a falhas de segurança em grades computacionais de larga escala, abordando a verificação de integridade na execução dos jobs. Desta forma, e possível excluir as unidades de processamento (nós) de má conduta interessadas em comprometer as aplicações, oferecendo, portanto, um ambiente de computação de alto desempenho formado apenas por nos confiáveis. A utilização de diagnostico em nível de sistema como estratégia contra ataques de manipulação de resultados de jobs mostra-se uma solução eficaz, visto que independe das plataformas de hardware utilizadas e é interoperavel com soluções de segurança locais, o que viabiliza seu emprego na maioria das middlewares de grades computacionais. Além disso, o modelo de diagnostico aqui apresentado organiza os nós em clusters lógicos, estabelecendo assim uma hierarquia entre os mesmos, de acordo com o papel de cada nó (executor, testador ou ultra-confiável), atribuído segundo seu histórico comportamental no ambiente. Essa abordagem permite que o diagnóstico seja feito de forma distribuída com a participação dos nós que possuem um nível mínimo de confiabilidade. Para validar esta estratégia, uma nova camada de segurança foi implementada em um simulador de grades, a fim de introduzir as asserções e os comportamentos descritos no modelo proposto. Os resultados obtidos atestam a sua eficácia em cenários com diferentes taxas de nós mal intencionados, oferecendo um índice de detecção de 100% e acurácia de 99,7% dos jobs processados, com 12,3% de custo de processamento.
6

Estudo do atraso de grupo em grandes compensadoras de dispersão

Rocha, Monica de Lacerda 13 October 1999 (has links)
Orientadores: Rui Fragassi Souza, Raman Kashya / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-07-26T08:48:30Z (GMT). No. of bitstreams: 1 Rocha_MonicadeLacerda_D.pdf: 15009595 bytes, checksum: 51316f6ab94a3a5f532f03b0f04ded3b (MD5) Previous issue date: 1999 / Resumo: Este trabalho descreve o estudo das grades de Bragg com chirp, em fibra, a partir de sua análise, caracterização e aplicação à compensação da dispersão em regime linear, com ênfase no aspecto oscilatório do atraso de grupo de grades não-apodizadas. Seu principal objetivo é o de investigar soluções ao problema deste caráter ondulatório através de simulações numéricas e implementações experimentais. Observou-se boa concordância entre ambas. Resultados de simulações sistêmicas são apresentados e discutidos. A penalidade devida às oscilações do atraso de grupo é avaliada e métodos práticos para seu controle são propostos. A redução destas oscilações, a partir dos métodos sugeridos, encontra aplicação em sistemas ópticos, operando em enlaces longos (acima de 100 km) de fibra convencional, com transmissão em taxas iguais ou superiores a 10 Gb/s / Abstract: This work describes a study of chirped fibre Bragg gratings, based on their analysis, characterization and application on dispersion compensation, for optical communication systems operating in a linear regime. It concentrates on the group delay oscillatory behaviour, observed in dispersion compensating gratings, known as Group Delay Ripple. The main scope of this work is to investigate possible solutions to that problem, rather than apodisation techniques, using numerical simulations and experimental implementations. A good agreement between both results was observed. Numerical system simulations are presented and discussed. The penalties due to the group delay oscillation is evaluated and new methods for controlling this ripple are suggested. Those techniques can be applied to long haul sytems (distances greater than 100 km and bit rates equal or greater than 10 Gb/s) operating with standard singlemodefibre / Doutorado / Doutor em Engenharia Elétrica
7

Exploring teachers' perceptions of the barriers and solutions to using one teacher laptop per class in a multi-grade context : the case of Intel®Teach-ICT implementation

Subramanien, Brenda January 2013 (has links)
This interpretive exploratory case study investigated the challenges and barriers to the multi-grade context in general, as well as to Information and Communication Technology (ICT) implementation in a multi-grade context. Possible solutions based on teacher perceptions were generated inductively within a three-level typology. The research took place in three phases. Pre-training data were gathered in the first phase, using an open-ended questionnaire (all participants: n=20); personal interviews (n=9); and two focus group interviews, which consisted of three participants per focus group. Training on the Intel® Teach ICT programme and the provision of laptops (one per teacher) constituted the second phase. The third phase included post-training data generation using an open-ended questionnaire (all participants) and two focus group interviews, which consisted of three participants per focus group, to elicit teacher perceptions of the training programme and their use of the laptops in the classroom after the training. The findings suggest that first order (school or meso level) challenges pertaining to multi-grade teaching relate to the lack of resources; curriculum challenges; learner related challenges; isolation, impact on communication and teaching; time constraints; and a work overload as a result of the multiple roles. Second order challenges (self or micro level) related to the perceived uncaring attitude of the Department of Basic Education that left teachers feeling hurt and neglected; the unpreparedness for the multi-grade context which demotivated teachers; and the negative perceptions the teachers had about their learners. Third order challenges (system level, beyond the school level or micro level) were related to the lack of Departmental support from officials; the lack of curriculum training for the multi-grade context; and the lack of support on various fronts. Regarding ICT related challenges, the findings suggest that first order barriers related to the lack of suitable infrastructure for ICT implementation; lack of peer support; lack of access to appropriate hardware and software; and lack of time. Second order barriers related to the negative beliefs in the self; negative perceptions about the learners’ ability to use the laptop; and negative beliefs related to teaching and learning. The third order barriers were related to the lack of support and assistance from the Department of Basic Education for ICT implementation. The findings suggest that the participants viewed the provisioning of enabling programmes for parents as an important solution to first order challenges, and a change in mindset as the most important solution for second order problems. Third order solutions included a “multi-grade Renaissance” towards a new model for multi-grade teaching; re-thinking the curriculum requirements regarding multi-grade teaching by the Department of Basic Education; increased support and training from the Department; incentives to teach with ICT in the multi-grade context; encouraging further research inmulti-grade teaching; providing sufficient resources; establishing partnerships with stakeholders; and the closure and merger of multi-grade schools. There was evidence that the laptops provided were used in a variety of ways after the Intel® Teach training by the participants, including email as a tool to communicate with their fellow multi-grade peers, which serve to break their sense of isolation. Quantitative data from the open-ended questionnaire confirmed an increase in the usage of the laptop after the Intel® Teach training intervention. Although the participants generally experienced the Intel teach training intervention as positive, they also identified negative experiences. These findings enabled the embedding of ‘self and sustainable support from stakeholders’ more explicitly in the professional teacher development ICT implementation framework of Du Plessis and Webb (2012b), which suggests that the Intel® Teach training intervention can be used as a vehicle to address ICT implementation within the multi-grade context. It is suggested that the Department of Basic Education should consider exposing all teachers to the Intel® Teach programme and assist multi-grade teachers by providing better on-going support and putting the necessary policies, implementation and infrastructure in place.
8

An Evaluation of Teaching Procedures and Curricula of the Primary Grades of Two Local Elementary Schools

Ballard, Irene January 1942 (has links)
An evaluation of teaching procedures and curricula of the primary grades of two local elementary schools according to criteria formulated from accepted educational psychology and democratic philosophy of educational leaders constitutes the problem at hand.
9

A case study of multigrade teaching in Canada: implications for South Africa

Muthayan, Saloshini January 2000 (has links)
This study examines multigrade teaching in selected schools in Canada and its implications for improving multigrade teaching in South Africa, where over 50 % of primary schools are multigrade and the teachers have not received preparation in multigrade teaching. The case study method was adopted because it allowed for 'an intensive, holistic description and analysis' of the multigrade classroom. The approach is interpretivist, based on the assumption that social phenomena are 'socially constituted' and 'valuationally based'. Research techniques included a literature review, interviews and observations. Four classrooms with grade combinations ranging from two grades to eight grades (Kindergarten to grade 7) were studied. Despite problems such as the lack of official recognition, inadequate teacher education and support - problems common to both Canada and South Africa - the Canadian teachers managed their classrooms effectively. This was indicated by their understanding of the children's needs, their integration of the curriculum for teaching across the grades and the learning areas, their use of effective instructional strategies and their involyement of parents in the classroom. A reason for their success may be that their teacher education includes child-centred, activity based approaches, integration of the curriculum, critical thinking, flexibility and effective instructional strategies, which they may adapt for effective multigrade teaching. The study found that successful multigrade teaching depended on the teacher. For South Africa, this may imply that intervention programmes should focus on relevant preparation and support for multigrade teachers. The emphasis on material resources in the implementation of Curriculum 2005 has not been balanced with adequate training on policy, curriculum and instructional strategies. Teacher education should include methodologies that are experiential, reflective and participatory. A variety of instructional strategies should be employed in the multigrade classroom. The respondents in the study believed further that multigrade teaching is more beneficial than single-grade teaching because it caters for the diversity of needs amongst children and allows for peer tutoring, thereby exploiting Vygotsky's theory of the 'zone of proximal development'. Thus, instead of viewing multigrade teaching as a temporary phenomenon, it should be viewed as an opportunity for improving school effectiveness.
10

The Personal Reading Interests of Third, Fourth, and Fifth Grade Children in Selected Arkansas Public Schools

Berry, Mary Ann 12 1900 (has links)
The purpose of this study was to determine the personal reading interests of students in the third, fourth and fifth grades and to determine if advances in technology in the past twenty years have changed their reading interests.

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