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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.
111

INCLUDING NONTARGETED INFORMATION WHEN TEACHING MULTIPLE EXEMPLARS OF SHAPES WITH THE CONSTANT TIME DELAY PROCEDURE

Matthews, Samantha D 01 January 2014 (has links)
Five elementary age students with moderate to severe intellectual disabilities were taught shape identification. A multiple probe design across behaviors, replicated across participants, was used to determine the effectiveness of constant time delay to determine the effectiveness of Constant Time Delay to teach shapes. Nontarget information was included in praise statements. All students met criterion on target information of shape identification. All students increased their ability to identify shape words, spell shape words, tell the number of sides of the shapes when presented and tell the number of angles of shapes presented. Generalization occurred during daily walks through the school and community as well as during the probe sessions.
112

Automatic clustering with application to time dependent fault detection in chemical processes

Labuschagne, P. J. January 2009 (has links)
Thesis (M.Eng.(Control Engineering))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.
113

Identification of Printed Nonsense Words for an Individual with Autism: A Comparison of Constant Time Delay and Stimulus Fading

January 2011 (has links)
abstract: This study compared a stimulus fading (SF) procedure with a constant time delay (CTD) procedure for identification of consonant-vowel-consonant (CVC) nonsense words for a participant with autism. An alternating treatments design was utilized through a computer-based format. Receptive identification of target words was evaluated using a computer format and the researcher conducted a generalization probe for expressive identification evaluation. Neither treatment condition resulted in consistent gains on the receptive identification measure. Both treatment conditions resulted in gains on the expressive identification assessment. The SF treatment condition was more efficient due to 1) accuracy in identifying all of the SF target words in fewer sessions than the CTD target words and 2) incidental learning that occurred as a result of exposure to additional SF words as distracter choices and in receptive identification assessments. Implications are discussed. / Dissertation/Thesis / Ph.D. Special Education 2011
114

On Identification and Control of Multivariable Systems Including Multiple Delays and Their Application to Anesthesia Control / 複数のむだ時間を含む多変数系の同定と制御およびそれらの麻酔制御への応用 / フクスウ ノ ムダ ジカン オ フクム タヘンスウケイ ノ ドウテイ ト セイギョ オヨビ ソレラ ノ マスイ セイギョ エ ノ オウヨウ

Sawaguchi, Yoshihito 24 March 2008 (has links)
This thesis proposes novel methods for identification and control of multivariable systems including multiple delays and describes their application to control of general anesthesia administration. First, an identification method for multivariable systems whose input and output paths have different time delays is presented. Second, a state predictor for multivariable systems whose input and output paths have different time delays is proposed. Third, the state predictor is used for constructing a state-predictive servo control system for controlled processes whose output paths have different time delays. A robust stability analysis method of the state-predictive servo control system is also examined. Furthermore, based on results of these theoretical studies, control systems for use in general anesthesia administration are developed. First, an identification method for multivariable systems whose input and output paths have different time delays is proposed. This method comprises two steps. In the first step, the delay lengths are estimated from the impulse response matrix identified from input and output (I/O) sequences using a subspace identification algorithm. In the second step, I/O sequences of a delay-free part are constructed from the original sequences and the delay estimates, and the system matrices of the delay-free part are identified. The proposed method is numerically stable and efficient. Moreover, it requires no complex optimization to obtain the delay estimates, nor does it require an assumption about the structure of the system matrices. Second, a state predictor is proposed for multivariable systems whose input and output paths have different time delays. The predictor consists of a full-order observer and a prediction mechanism. The former estimates a vector consisting of past states from the output. The latter predicts the current state from the estimated vector. The prediction error converges to zero at an arbitrary rate, which can be determined using pole assignment method, etc. In the proposed predictor, the interval length of the finite interval integration fed to the observer is shorter than that of an existing delay-compensating observer. Consequently, the proposed predictor is more numerically accurate than the delay-compensating observer. Using the proposed state predictor, a design method of a state-predictive servo controller is described for multivariable systems whose output paths have different time delays. Furthermore, a sufficient stability condition of the state-predictive servo control system against parameter mismatches is derived. Using a characteristic equation of the perturbed closed-loop system, a stability margin can be given on a plane whose axes correspond to the magnitudes of the mismatches on system matrices and on delay lengths. In the remainder of this thesis, development of anesthesia control systems is described to illustrate an application of the theoretical results described above. First, a hypnosis control system is presented. This system administers an intravenous hypnotic drug to regulate an electroencephalogram-derived index reflecting the patient’s hypnosis. The system comprises three functions: i) a model predictive controller that can take into account effects of time delay adequately, ii) an estimation function of individual parameters, and iii) a risk-control function for preventing undesirable states such as drug over-infusion or intra-operative arousal. Results of 79 clinical trials show that the system can reduce the total amount of drug infusion and maintain hypnosis more accurately than an anesthesiologist’s manual adjustment. Second, a simultaneous control system of hypnosis and muscle relaxation is described. For development of this system, a multivariable model of hypnosis and muscle relaxation is identified using the method proposed in this thesis. Then a state-predictive servo control system is designed for controlling hypnosis and muscle relaxation. Finally, the control system’s performance is evaluated through simulation. The resultant simultaneous control system satisfies the performance specifications of settling time, disturbance rejection ability, and a robust stability range. Although this system is not fully developed, the procedure of constructing this control system demonstrates the effectiveness of the proposed methods: the identification method for systems whose input and output paths have different time delays and the design and stability analysis methods of the state-predictive servo control system. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13820号 / 工博第2924号 / 新制||工||1432(附属図書館) / 26036 / UT51-2008-C736 / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 小林 哲生, 教授 萩原 朋道, 准教授 古谷 栄光 / 学位規則第4条第1項該当
115

Análise do comportamento de juntas de CCR com alto teor de finos / Behavior of RCC joints with high powder content

Traboulsi, Maurice Antoine January 2007 (has links)
A tecnologia do concreto compactado com rolo tem se desenvolvido e transformado o cenário das construções de barragens, modernizando os conceitos sobre os processos construtivos, além de se mostrar uma técnica competitiva em comparação com os métodos já consagrados de construção de Barragens de terra, enrocamento e enrocamento com face de concreto. Até a década de 70 era usual o lançamento de um elemento de ligação entre camadas de concreto. Nesta época, estudos realizados pelo U.S. Bureau of Reclamation e U.S. Army Corps of Engineers mostraram que a sua utilização era desnecessária, desde que as juntas fossem cuidadosa e adequadamente preparadas. A construção da barragem de Willow Creek, com CCR sem nenhuma especificação de um elemento de ligação entre as camadas de concretagem, acabou resultando num alto nível de percolação de água. Devido a este fato, os grandes projetistas de estruturas hidráulicas e de barragens passaram a adotar um concreto de berço, lançado entre as camadas de CCR, abrangendo entre 30 % da seção superficial da junta, a partir do paramento de montante, até toda a camada. Neste projeto de pesquisa foi proposta a execução de maciços experimentais em laboratório, os quais simulam uma pequena fatia de uma barragem de CCR. Para simular o lançamento e adensamento do concreto destes maciços utilizou-se um equipamento existente no Laboratório de Concreto de FURNAS Centrais Elétricas S.A., localizado em Goiânia-GO. Foram confeccionados 11 maciços experimentais, nos quais foram realizadas avaliações referentes ao intervalo de lançamento entre camadas de concreto compactado com rolo, variando-se o tempo de exposição, a temperatura ambiente de lançamento, o tipo de tratamento da junta e a utilização de argamassa de ligação, ou seja, procurou-se avaliar o grau de maturidade das juntas, a partir do qual são necessárias providências para promover uma adequada aderência entre camadas e mostrar a importância da confecção prévia de maciços experimentais em laboratório para auxiliar a tomada de decisão durante a elaboração do projeto. / The roller compacted concrete technology has been increasable developed and, consequently, modified the dam constructions procedures, leading to improved concepts about the construction processes, besides presenting technical competitively when compared to earth, rockfill and concrete faced rockfill gravity dams construction methodology. The use of a bonding element (concrete or mortar), between concrete layers was common in the 70´s. At that time, studies conducted by the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers showed that this technique was unnecessary in traditional dam constructions for the cases of well and strictly prepared joints. The Willow Creek dam construction, using RCC without any specification about bonding element between layers, presented a high level of percolation. Since that, great hydraulic structures designers adopted a bed of small aggregate concrete, placed between RCC layers in about 30% of the superficial section of joint from the upstream face. To the herein research it was proposed the execution of experimental laboratory bulks simulating a small part of a RCC dam. For the simulation of placing and compaction of concrete it was used the equipment owned by FURNAS CENTRAIS ELETRICAS S.A., at the laboratory of Goiania, Brazil. Eleven experimental bulks were produced, in which were assessed the exposure of RCC layers in different time delays and temperatures, varying the layer concrete surface treatment and the use of mortar between layers in order to evaluate the maturity degree of joints and to define the procedures to a suitable bonding between layers. The studies show the importance of laboratory test fills during the design phases, as useful tools to help the technical decision processes.
116

Análise do comportamento de juntas de CCR com alto teor de finos / Behavior of RCC joints with high powder content

Traboulsi, Maurice Antoine January 2007 (has links)
A tecnologia do concreto compactado com rolo tem se desenvolvido e transformado o cenário das construções de barragens, modernizando os conceitos sobre os processos construtivos, além de se mostrar uma técnica competitiva em comparação com os métodos já consagrados de construção de Barragens de terra, enrocamento e enrocamento com face de concreto. Até a década de 70 era usual o lançamento de um elemento de ligação entre camadas de concreto. Nesta época, estudos realizados pelo U.S. Bureau of Reclamation e U.S. Army Corps of Engineers mostraram que a sua utilização era desnecessária, desde que as juntas fossem cuidadosa e adequadamente preparadas. A construção da barragem de Willow Creek, com CCR sem nenhuma especificação de um elemento de ligação entre as camadas de concretagem, acabou resultando num alto nível de percolação de água. Devido a este fato, os grandes projetistas de estruturas hidráulicas e de barragens passaram a adotar um concreto de berço, lançado entre as camadas de CCR, abrangendo entre 30 % da seção superficial da junta, a partir do paramento de montante, até toda a camada. Neste projeto de pesquisa foi proposta a execução de maciços experimentais em laboratório, os quais simulam uma pequena fatia de uma barragem de CCR. Para simular o lançamento e adensamento do concreto destes maciços utilizou-se um equipamento existente no Laboratório de Concreto de FURNAS Centrais Elétricas S.A., localizado em Goiânia-GO. Foram confeccionados 11 maciços experimentais, nos quais foram realizadas avaliações referentes ao intervalo de lançamento entre camadas de concreto compactado com rolo, variando-se o tempo de exposição, a temperatura ambiente de lançamento, o tipo de tratamento da junta e a utilização de argamassa de ligação, ou seja, procurou-se avaliar o grau de maturidade das juntas, a partir do qual são necessárias providências para promover uma adequada aderência entre camadas e mostrar a importância da confecção prévia de maciços experimentais em laboratório para auxiliar a tomada de decisão durante a elaboração do projeto. / The roller compacted concrete technology has been increasable developed and, consequently, modified the dam constructions procedures, leading to improved concepts about the construction processes, besides presenting technical competitively when compared to earth, rockfill and concrete faced rockfill gravity dams construction methodology. The use of a bonding element (concrete or mortar), between concrete layers was common in the 70´s. At that time, studies conducted by the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers showed that this technique was unnecessary in traditional dam constructions for the cases of well and strictly prepared joints. The Willow Creek dam construction, using RCC without any specification about bonding element between layers, presented a high level of percolation. Since that, great hydraulic structures designers adopted a bed of small aggregate concrete, placed between RCC layers in about 30% of the superficial section of joint from the upstream face. To the herein research it was proposed the execution of experimental laboratory bulks simulating a small part of a RCC dam. For the simulation of placing and compaction of concrete it was used the equipment owned by FURNAS CENTRAIS ELETRICAS S.A., at the laboratory of Goiania, Brazil. Eleven experimental bulks were produced, in which were assessed the exposure of RCC layers in different time delays and temperatures, varying the layer concrete surface treatment and the use of mortar between layers in order to evaluate the maturity degree of joints and to define the procedures to a suitable bonding between layers. The studies show the importance of laboratory test fills during the design phases, as useful tools to help the technical decision processes.
117

Improving Proctoring by Using Non-Verbal Cues During Remotely Administrated Exams

January 2015 (has links)
abstract: This study investigated the ability to relate a test taker’s non-verbal cues during online assessments to probable cheating incidents. Specifically, this study focused on the role of time delay, head pose and affective state for detection of cheating incidences in a lab-based online testing session. The analysis of a test taker’s non-verbal cues indicated that time delay, the variation of a student’s head pose relative to the computer screen and confusion had significantly statistical relation to cheating behaviors. Additionally, time delay, head pose relative to the computer screen, confusion, and the interaction term of confusion and time delay were predictors in a support vector machine of cheating prediction with an average accuracy of 70.7%. The current algorithm could automatically flag suspicious student behavior for proctors in large scale online courses during remotely administered exams. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2015
118

Uma contribuição ao estudo das redes mutuamente conectadas de DPLLs usando modelos de tempo discreto. / A contribution to study of mutually-connected DPLL networks using discrete time models.

Marcus Vinícius Richardelle Unzueta 07 July 2008 (has links)
Este trabalho tem por objetivo apresentar uma nova forma de analisar as redes de sincronismo de fase mutuamente conectadas. Estas redes são formadas por Phase-Locked Loops digitais ou DPLLs. O sinal gerado por cada DPLL é enviado a todos os demais dispositivos, formando a rede mutuamente conectada. Parte-se do pressuposto de que as ligações entre os dispositivos são dotadas de atrasos, o que dificulta o tratamento do problema. No entanto, é apresentado aqui um método para análise das malhas de sincronismo via discretização do modelo de tempo contínuo, objetivando dirimir essa dificuldade, já que atrasos são facilmente representados em modelos de tempo discreto. Para tanto, o modelo da rede no espaço de estados é equacionado a partir da rede. Esse modelo no espaço de estados é, então, discretizado e, enfim, pode-se determinar o estado síncrono da rede incluindo a freqüência de sincronismo e analisar sua estabilidade. Como se poderá constatar, escolhendo um período de amostragem adequado, pode-se representar o comportamento das redes de sincronismo com modelos discretos, obtendo elevado grau de precisão. / This work introduces a new method for studying a mutually-delayed-connected network of Digital Phase-Locked Loops DPLLs. The signal generated by a DPLL in the network is sent to all other devices in this same network. Because of delayed signals, it is difficult to treat this problem. So, its shown here a method for analyzing the networks via discretization of continuous time delay model in order to deal with this issue easily, considering that delays are naturally represented in discrete time models. First of all, a continuous state space model is obtained from mutually-connected network. Then, this model is discretized and, finally, the synchronous state can be determined and the stability can be analyzed. As shown below, choosing a proper time sample, the behavior of mutually-delayed-connected networks can be approximately represented by a discrete time model.
119

ContribuiÃÃes ao estudo de sistemas SISO e MIMO com atraso de transporte / Contribuitions to the study of SISO and MIMO systems with dead-time

Wilkley Bezerra Correia 22 January 2016 (has links)
This work presents a contribution to the study of control of dead-time systems. Within this context, it is presented a literature review covering from the Smith predictor until its recent variations. For the state space representation dead-time is normally dealt under the discrete-time perspective, where it is included as state augmentation. In the first case, this work proposes a novel control structure with simple tuning rules, able to deal with single input and output systems that presents multiple delays due to multiple internal paths. However, the design method allows the proposed structure to be readily applied for the single delay case. The study is extended for the state space representation, where it is presented a modification to a predictor recently presented in literature, in order to use it as a predictor-observer within the state space representation. In this case, all the matrices involved in the observer have the same order as those of the plant, i. e., there is no need of the state augmentation to deal with dead-time. Hence, the well known techniques for the optimal and robust control may be applied for multivariable delayed systems. Besides, an alternative way of tuning for the LQG control, based on the T-polynomial approach, is proposed. In this case, the technique may be applied for both the delay free systems and dead-time systems. The latter by applying the modified predictor mentioned earlier in the observer structure. Additionally, it is also proposed a new predictor structure, based on the CARIMA model with T-polynomial, for dead-time systems. This work is full of examples throughout the text which are suitable for both the control strategies studied herein and the proposed ones, applicable for stable, unstable or integrating systems, as well as multivariable systems. Case studies for laboratories plants validate the effectiveness of the discussed methods. / Este trabalho apresenta uma contribuiÃÃo ao estudo de controle de sistemas dinÃmicos que exibem atraso de transporte. Nesse contexto, apresenta-se uma revisÃo bibliogrÃfica que traz desde o surgimento do preditor de Smith atà algumas de suas variaÃÃes mais recentes. Na representaÃÃo baseada em espaÃo de estados à comum que se tenha a abordagem em tempo discreto, em que o atraso de transporte à normalmente incluÃdo atravÃs do aumento da ordem do estado. No primeiro caso, este trabalho traz a proposta de uma nova estrutura de controle, de sintonia simplificada, capaz de lidar com sistemas de entrada e saÃda Ãnicas, mas que apresentam mÃltiplos atrasos em caminhos diversificados internamente. A metodologia considerada, entretanto, permite que a estrutura proposta possa ser facilmente aplicada a sistemas com atraso simples. O estudo à ampliado para a representaÃÃo em espaÃo de estados no tempo discreto, em que apresenta-se uma abordagem que leva à adaptaÃÃo de um preditor proposto recentemente na literatura para atuar como observador de estados. Neste caso, tem-se a vantagem de que todas as matrizes envolvidas tem a mesma ordem daquelas que descrevem o sistema, ou seja, nÃo hà aumento da ordem do estado. Assim, as tÃcnicas conhecidas de controle robusto e Ãtimo para a representaÃÃo em espaÃo de estados podem ser aplicadas a sistemas com mÃltiplas entradas e saÃdas. Apresenta-se ainda uma forma alternativa de sintonia do controle LQG, baseada no polinÃmio-T. Neste caso, a sintonia proposta pode ser aplicada tanto para sistemas sem atraso de transporte quanto para aqueles com atraso quando se considera a adaptaÃÃo da estrutura do preditor no observador de estados. AlÃm disso, este trabalho apresenta ainda a proposta de um novo preditor cuja estrutura à baseada no modelo CARIMA com polinÃmio-T, aplicado a sistemas com atraso de transporte. O trabalho à repleto de exemplos em que aplicam-se tanto as estratÃgias de controle estudadas quanto as propostas, a sistemas estÃveis, instÃveis ou integradores em malha aberta, bem como a sistemas multivariÃveis. Estudos de caso aplicados a plantas de laboratÃrio comprovam a eficiÃncia dos mÃtodos discutidos.
120

Análise do comportamento de juntas de CCR com alto teor de finos / Behavior of RCC joints with high powder content

Traboulsi, Maurice Antoine January 2007 (has links)
A tecnologia do concreto compactado com rolo tem se desenvolvido e transformado o cenário das construções de barragens, modernizando os conceitos sobre os processos construtivos, além de se mostrar uma técnica competitiva em comparação com os métodos já consagrados de construção de Barragens de terra, enrocamento e enrocamento com face de concreto. Até a década de 70 era usual o lançamento de um elemento de ligação entre camadas de concreto. Nesta época, estudos realizados pelo U.S. Bureau of Reclamation e U.S. Army Corps of Engineers mostraram que a sua utilização era desnecessária, desde que as juntas fossem cuidadosa e adequadamente preparadas. A construção da barragem de Willow Creek, com CCR sem nenhuma especificação de um elemento de ligação entre as camadas de concretagem, acabou resultando num alto nível de percolação de água. Devido a este fato, os grandes projetistas de estruturas hidráulicas e de barragens passaram a adotar um concreto de berço, lançado entre as camadas de CCR, abrangendo entre 30 % da seção superficial da junta, a partir do paramento de montante, até toda a camada. Neste projeto de pesquisa foi proposta a execução de maciços experimentais em laboratório, os quais simulam uma pequena fatia de uma barragem de CCR. Para simular o lançamento e adensamento do concreto destes maciços utilizou-se um equipamento existente no Laboratório de Concreto de FURNAS Centrais Elétricas S.A., localizado em Goiânia-GO. Foram confeccionados 11 maciços experimentais, nos quais foram realizadas avaliações referentes ao intervalo de lançamento entre camadas de concreto compactado com rolo, variando-se o tempo de exposição, a temperatura ambiente de lançamento, o tipo de tratamento da junta e a utilização de argamassa de ligação, ou seja, procurou-se avaliar o grau de maturidade das juntas, a partir do qual são necessárias providências para promover uma adequada aderência entre camadas e mostrar a importância da confecção prévia de maciços experimentais em laboratório para auxiliar a tomada de decisão durante a elaboração do projeto. / The roller compacted concrete technology has been increasable developed and, consequently, modified the dam constructions procedures, leading to improved concepts about the construction processes, besides presenting technical competitively when compared to earth, rockfill and concrete faced rockfill gravity dams construction methodology. The use of a bonding element (concrete or mortar), between concrete layers was common in the 70´s. At that time, studies conducted by the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers showed that this technique was unnecessary in traditional dam constructions for the cases of well and strictly prepared joints. The Willow Creek dam construction, using RCC without any specification about bonding element between layers, presented a high level of percolation. Since that, great hydraulic structures designers adopted a bed of small aggregate concrete, placed between RCC layers in about 30% of the superficial section of joint from the upstream face. To the herein research it was proposed the execution of experimental laboratory bulks simulating a small part of a RCC dam. For the simulation of placing and compaction of concrete it was used the equipment owned by FURNAS CENTRAIS ELETRICAS S.A., at the laboratory of Goiania, Brazil. Eleven experimental bulks were produced, in which were assessed the exposure of RCC layers in different time delays and temperatures, varying the layer concrete surface treatment and the use of mortar between layers in order to evaluate the maturity degree of joints and to define the procedures to a suitable bonding between layers. The studies show the importance of laboratory test fills during the design phases, as useful tools to help the technical decision processes.

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