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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Increasing Reading Performance Through a Teacher's Assistant and Data-Based Instruction

Marks, Lori J. 01 August 1995 (has links)
No description available.
22

Evaluation of the First Year of a Statewide Problem Solving/Response to Intervention Initiative: Preliminary Findings

Castillo, Jose Michael, Educational Specialist 15 June 2009 (has links)
This program evaluation study examined the relationship between Problem Solving/Response to Intervention (PS/RtI) training and technical assistance and educator and implementation outcomes following the first year of a 3-year project. Educators from 40 pilot schools in eight districts participating in the study received ongoing professional development targeting the rationale for the initiative, systems change issues, and the steps of the PS/RtI model. Data on educator beliefs, educator perceived and demonstrated PS/RtI skills, and PS/RtI implementation were collected throughout the year from the 40 pilot schools as well as 33 comparison schools. To examine the relationships between PS/RtI training and technical assistance and preliminary outcomes, a series of multi-level models were conducted. Results of the analyses suggested that the ongoing professional development provided during the first year related to some outcomes. Specifically, PS/RtI training and technical assistance appeared to be positively related to increases in the beliefs and perceived skills of educators. The relationship between professional development activities and other outcomes targeted during the first year (i.e., demonstrated skills and implementation) was unclear. Potential explanations for the findings from this study and implications for future research are discussed.
23

Relationship Between Teachers' Use of Academic Progress Data and Students' Test Scores

Egan, Amanda Egan 01 January 2017 (has links)
A small private secondary school in Mexico implemented periodic progress testing with the intention of individualizing education of its students. The relationship between teachers' use of Measures of Academic Progress (MAP) data and students' mathematics and reading gain scores was not known. The purpose of this study was to determine whether the frequency of teachers' use of MAP data or student profiles was related to students' MAP mathematics and reading test gain scores between 2 years of test administrations. The theoretical framework for the study was Dewey's, Kolb's, and Vygotsky's ideas on pragmatism and constructivism, which support students' opportunities for growth in learning through realization of their strengths and talents. The mathematics and reading MAP gain scores of 76 students were examined, along with 8 teachers' responses from a questionnaire on teachers' frequency of use of MAP data or student profiles. Data were analyzed using analyses of variance. Results indicated significant differences in students' MAP gain scores in reading when their teachers reported using MAP data at least once per week (F = 4.086, p = 0.001) or online student profiles at least once per month (F = 3.638, p = 0.013). Targeted training videos and materials were created to support teachers' use of MAP results to inform instruction at the study site. Implications for social change include encouraging teachers and administrators to meet the individual needs of students, which may result in increased student reading and mathematics scores, graduation rates, and latitude in vocation selection.
24

Total Quality Management in Central America: A case study in leadership and data-based dialogue

Osland, Asbjorn January 1994 (has links)
No description available.
25

Critério otimizado para projeto de controle regulatório baseado em dados

Bordignon, Virgínia January 2018 (has links)
Métodos de controle por modelo de referência, usualmente encontrados na literatura de controle baseado em dados, têm como principal característica a especificação do desempenho desejado em malha fechada através de um modelo de referência. Estes métodos são, no entanto, comumente desenvolvidos para tratar o problema de seguimento de referência, em detrimento do comportamento relativo à perturbação de carga. Nesse sentido, recentemente foi desenvolvido o método de controle baseado em dados Virtual Disturbance Feedback Tuning – VDFT, que pode ser interpretado como um método de controle por modelo de referência para perturbação, em que o controlador é sintonizado para alcançar em malha fechada o comportamento regulatório especificado. A escolha no entanto do modelo de referência para perturbação mostra-se desafiadora, especialmente considerando o cenário em que pouca ou nenhuma informação sobre o modelo paramétrico do sistema está disponível. Dessa forma, este trabalho tem como objetivo estudar o impacto da escolha deste modelo sobre a sintonia do controlador utilizando o método VDFT e propor uma abordagem sistemática para lidar com essa variável de projeto. A solução aqui concebida é a de flexibilizar o modelo de referência para perturbação e identificar parte do seu numerador juntamente aos parâmetros do controlador que, associada a um conjunto de diretivas de projeto, permitem aproximar o comportamento em malha fechada do inicialmente especificado. Esse resultado viabiliza a utilização do método VDFT com critério flexível no contexto de uma estrutura hierárquica de controle, em que uma malha externa de controle preditivo é associada à malha de controle por VDFT, evitando a etapa de identificação de um modelo para o processo. Por fim, a formulação do método VDFT, assim como sua adaptação flexível, é estendida a fim de levar em conta processos multivariáveis. Experimentos e resultados em simulação ilustram as contribuições deste trabalho. / Model reference control methods, usually found within data-based control literature, have as main feature the specification of the desired closed-loop performance through a reference model. These methods are however commonly developed to address the set point tracking problem, to the disadvantage of load disturbance rejection. In this sense, the data-based control method Virtual Disturbance Feedback Tuning – VDFT was recently developed, which could be interpreted as a model reference control method for disturbance, in which the controller is tuned in order to reach in closed-loop the specified regulatory behavior. Nonetheless, the choice of the disturbance reference model is challenging, especially considering the scenario where little or no information on the process’ parametric model is available. This work aims therefore to study the impact of the disturbance reference model choice on the controller tuning using the VDFT method and to propose a systematic approach to deal with this design variable. The solution here conceived is to loosen the disturbance reference model and identify part of its numerator along with the controller parameters, which, associated with a set of design directions, allow the closed-loop behavior to be drawn closer to the one initially specified. This result enables the use of the VDFT method with flexible criterion in the context of a hierarchical control structure, in which an external predictive control loop is associated to the VDFT control loop, avoiding thus the identification of a process model. Finally, VDFT method’s formulation, as well as its flexible adaptation, is extended in order to take into account multivariable processes. Experiments and simulation results illustrate the contributions of this work.
26

Ajuste baseado em dados de controladores : o método VRFT embarcado em um aplicativo móvel

Garcia, Cristiane Silva January 2017 (has links)
O método VRFT (Virtual Reference Feedback Tuning) é um método baseado em dados utilizado para ajustar os parâmetros de um controlador. Uma das vantagens deste método é que não é necessário um conhecimento detalhado do modelo do processo a ser controlado. Neste trabalho é apresentado o desenvolvimento de um aplicativo Android que utiliza o método VRFT, e uma versão recursiva do mesmo, para ajustar os parâmetros de um controlador PID com base nos dados de entrada e saída coletados de um experimento realizado no processo. O experimento pode ser configurado, inicializado, monitorado, e interrompido através da aplicação móvel. Para viabilizar a comunicação com o controlador também foram desenvolvidos um gateway Bluetooth-Modbus e um protocolo de comunicação simples, que opera sobre o serviço de comunicação serial do protocolo Bluetooth. A solução proposta foi validada através de experimentos realizados em processos simulados e em um processo real, mostrando bons resultados em ambos os casos. / The Virtual Reference Feedback Tuning (VRFT) method is a data-driven method employed to tune the parameters of a controller. An advantage of this method lies in the fact that it does not need a detailed knowledge of the process model. This work presents the development of an Android application which employs the VRFT method and a newly developed recursive version of it to tune a PID controller based upon the data collected from an experiment conducted on the process. The experiment can be set up, started, monitored, and stopped from inside the mobile application. To communicate with the controller a Bluetooth-Modbus gateway and an application layer protocol, designed over the Bluetooth serial communication service, are employed, both newly developed. Finally, the entire solution is verified in two steps: first some experiments were conducted on a simulated process, then another experiment was conducted to tune a real commercial controller, both showing good results.
27

Nova metodologia para o desenvolvimento de inferências baseadas em dados

Fleck, Thiago Dantas January 2012 (has links)
As inferências têm diversas aplicações na indústria de processos químicos, sendo essenciais no sucesso de projetos de controle avançado. O desempenho do controle será sempre ligado ao desempenho da inferência, sendo importante a manutenção da sua qualidade ao longo do tempo. Neste trabalho, uma nova metodologia é sugerida para o desenvolvimento de inferências baseadas em dados seguindo uma abordagem segmentada com o objetivo de facilitar a sua manutenção. A nova proposta consiste em modelar a parte estacionária separada da parte dinâmica, diferentemente do que é feito na metodologia tradicional, onde o modelo dinâmico é gerado diretamente dos dados de processo. O modelo estacionário é obtido através de uma regressão PLS (Partial Least Squares), enquanto as dinâmicas são inseridas posteriormente utilizando-se um algoritmo de otimização. A técnica é aplicada a uma coluna de destilação e o resultado obtido é semelhante ao de inferências dinâmicas e estáticas desenvolvidas com métodos tradicionais. Outras etapas do desenvolvimento de inferências também são investigadas. Na seleção de variáveis, métodos estatísticos são comparados com a busca exaustiva e se conclui este último deve ser usado como padrão, visto que custo computacional não é mais um problema. Também são apresentadas boas práticas no pré-tratamento de dados, remoção do tempo morto do cromatógrafo modelado e detecção de estados estacionários. / Soft-sensors have several applications in the chemical processes industry and are essential for the success of advanced control projects. Its performance will always be linked to the performance of the soft-sensor, so it is important to maintain its quality over time. In this paper, a new methodology is suggested for the development of data-based soft-sensors following a segmented approach in order to facilitate its maintenance. The new proposal is to model the stationary part separated from the dynamic, unlike the traditional methodology where the dynamic model is generated directly from process data. The stationary model is obtained by a PLS (Partial Least Squares) regression, while the dynamics are inserted using an optimization algorithm. The technique is applied to a distillation column and its performance is similar to dynamic and static soft-sensors developed using traditional methods. Other steps in the development of soft-sensors are also investigated. In variable selection issue, statistical methods are compared with the testing of all possibilities; the latter should be used as default, since computational cost is no longer a problem. We also present best practices in data pre-processing, gas chromatograph dead-time removal and steady state detection.
28

A New Field-data Based Eaf Model Applied To Power Quality Studies

Gol, Murat 01 September 2009 (has links) (PDF)
Electric Arc Furnace (EAF) modeling has been a common research area to date. This thesis work proposes a new field-data based EAF-specific model. The data used in developing the proposed model is obtained from field measurements of instantaneous voltages and currents of EAF the plants. This model presents the dynamic behavior of the EAF system including all its parts, which are the EAF transformer, the secondary circuit, the electrodes moving and the arc itself. It consists of a cascade connected variable-resistance and &ndash / inductance combination to represent the variation in time of the fundamental frequency, and a current source in parallel with it to inject the harmonics and interharmonics content of the EAF current. The proposed model is capable of representing both AC and DC EAFs, whose controllers&rsquo / set points are the impedance values seen from the low voltage (LV) side of the EAF transformer. The validity of the proposed model has been verified by comparing EMTDC/PSCAD simulations of the model with the field measurements. The results obtained have shown quite satisfactory correlation between the behavior of the proposed model and v the actual EAF operation. To show the advantages of the model while developing FACTS solutions for power quality (PQ) problem mitigation of a given busbar supplying single- or multi-EAF installations, various applications are presented.
29

Teacher Perspectives on the Instructional Impact of the Florida Alternate Assessment

Hawley, Katherine 01 January 2013 (has links)
This study examined special education teachers' perspectives of the instructional impact of the Florida Alternate Assessment (FAA) for students with significant cognitive disabilities. Through purposeful sampling, six special education teachers who serve students with significant cognitive disabilities and had experience administering the FAA were identified. Interviews posed questions about how they used the FAA to impact their instructional decision-making, how the FAA has influenced how the development of Individualized Education Program (IEP) goals, and how the FAA impacted how they defined access to the general education curriculum. The interviews, along with IEP artifacts, and a research journal formed the research design. Results revealed 8 major themes and 18 sub-themes. Teachers reported that the FAA ignores the complex needs of their students, and highlighted the curricular tensions between academics and life skills. A third of the teachers indicated they have created and adopted curriculum to mirror the FAA, and five out of the six teachers integrated more daily assessments similar to the FAA. In addition, the study revealed varied results for utilizing FAA results on IEP development and writing goals. Finally, teachers had varied beliefs on the value of curriculum content standards called access points for students with significant cognitive disabilities. Most of the teachers stated that higher standards lead to higher expectations. The results also revealed teachers' perspectives of the instructional impact of the FAA were influenced by their teaching context: center setting versus general education setting. Implications for future research and practice are included.
30

Contribuições para métodos de controle baseados em dados obtidos em apenas um experimento

Campestrini, Lucíola January 2010 (has links)
Este trabalho apresenta algumas contribuições para métodos de controle baseados em dados obtidos em apenas um experimento, a fim de torná-los mais atrativos quanto à aplicação em processos industriais. A partir de dados obtidos em experimentos no processo, os métodos baseados em dados estimam os parâmetros de um controlador de estrutura fixa por meio da minimização do erro entre a saída do sistema real em malha fechada e uma saída desejada, dada por um modelo de referência. O método Virtual Reference Feedback Tuning - VRFT é o método mais expressivo na literatura que estima os parâmetros do controlador usando apenas uma batelada de dados, mas o mesmo apresenta alguns inconvenientes em sua formulação que limitam a sua aplicação. Neste trabalho, o método VRFT é modificado de forma que se obtém um método VRFT flexível, o qual minimiza um critério flexível, pelo qual são estimados tanto os parâmetros do controlador quanto os parâmetros do numerador do modelo de referência; assim, caso a planta que se deseja controlar seja de fase não-mínima, o critério é capaz de estimar esses zeros e os mesmos devem ser incluídos no modelo de referência que será utilizado no projeto do controlador. Além disso, em sistemas com ruído, o método VRFT necessita de uma variável instrumental para que a estimativa dos parâmetros do controlador seja não-polarizada. Para eliminar a necessidade de usar variáveis instrumentais, um novo método de controle baseado em dados é proposto, o qual é descrito sob a ótica de identificação. Este método pode ser visto como a identificação de um sistema, no qual a função de transferência do processo é reparametrizada em função do controlador ideal e do modelo de referência. Além disso, estende-se a teoria de projeto de experimento com solução baseada em restrições LMI para o caso da identificação do controlador ótimo. Todas essas contribuições são ilustradas através de simulações. / This work presents some contributions to data-based control methods where data is obtained in only one experiment, in order to make them more attractive to industrial process applications. Using data from experiments on the process, data-based methods estimate the parameters of fixed structure controller, through the minimization of the error between the closed loop response of the system and the desired response, given by a reference model. The Virtual Reference Feedback Tuning - VRFT method is the most expressive method in the literature that estimates the controller parameters using only one batch of data, but this method presents some inconveniences in its formulation which limit its application. In this work, the VRFT method is modified in order to obtain a flexible VRFT method, which minimizes a flexible criterion, and then obtains the controller parameters together with the parameters related to the reference model numerator; thus, if the plant which we want to control is non-minimum phase, then the criterion is able to estimate these zeros and they need to be included in the reference model that will be used in the control design. Besides, when dealing with noisy systems, the VRFT method needs an instrumental variable so the controller parameters estimate is unbiased. In order to eliminate this necessity, a new data-based control is proposed in this work, which is formulated using identification theory. This method can be seen as the identification of a system, where the process transfer function is reparameterized as a function of the ideal controller and the reference model. Besides, we extend the experimental design theory where the problem is solved using LMI constraints to the case of the optimal controller identification method. All these contributions are illustrated through simulations.

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