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91.
In this paper, an adaptive Takagi–Sugeno (T–S) fuzzy controller based on reinforcement learning for controlling the nonlinear dynamical systems is proposed. The parameters of the T–S fuzzy system are learned using the reinforcement learning based on the actor-critic method. This on-line learning algorithm improves the controller performance over the time, which it learns from its own faults through the reinforcement signal from the external environment and tries to reinforce the T–S fuzzy system parameters to converge. The updating parameters are developed using the Lyapunov stability criterion. The proposed controller is faster in learning than the T–S fuzzy that parameters learned using the gradient descent method under the same conditions. Moreover, it is able to handle the load changes and the system uncertainties. The test is carried out based on two mathematical models. In addition, the proposed controller is applied practically for controlling a direct current (DC) shunt machine. The results indicate that the response of the proposed controller has a good performance compared with other controllers.  相似文献   
92.
An adaptive numerical method for solving multi-delay optimal control problems with piecewise constant delay functions is introduced. The proposed method is based on composite pseudospectral method using the well-known Legendre–Gauss–Lobatto points. In this approach, the main problem converts to a mathematical optimization problem whose solution is much more easier than the original one. The necessary conditions of optimality associated to nonlinear piecewise constant delay systems are derived. The method is easy to implement and provides very accurate results.  相似文献   
93.
Written for teachers, who generally lack a sufficient knowledge of how people learn, Pritchard's book aims at enhancing the effectiveness and efficiency of education through raising teachers' understanding of learning theory. However, it does not do so very effectively: even if you are a keen teacher, you will probably find only parts of much interest or use. Mohammad Ali Salmani Nodoushan  相似文献   
94.
This article reports the second stage of a study examining an academic partnership in which Bangladeshi doctoral students in a western university focus their research in the grounded context of Bangladesh and investigate the processes for change. After briefly outlining the previous published stage which examined the academic trade in higher education with developing countries, the article builds on the concept of fair academic trade to critically reflect on the development of a doctoral learning community, a publication project and three specific doctoral studies. The methodological approach is one of participatory action research, with focus on critical reflection on practice.  相似文献   
95.
We examined written expression performance in a sample of adolescents with ADHD and subthreshold ADHD using two different strategies: examining performance on standardized measures of written expression and using other indicators of written expression developed in this study. We examined associations between standardized measures of written expression, cognitive processing measures (working memory, processing speed, language, fine motor ability, and reading efficiency) and behavioral ratings of ADHD by parents and teachers. We also developed a coding scheme for a writing sample to measure productivity and the ratio of self-corrections to errors. The results indicated that written expression performance was most consistently associated with cognitive processing measures and not behavioral ratings of ADHD, based on correlational and simultaneous regression analyses. These results were consistent in the analyses with both the standardized measures and the coding scheme measures of written expression. Findings generally remained robust, regardless of whether participants who met criteria for a learning disability were included or excluded in the analyses. The current results suggest that written expression difficulties in adolescents with ADHD are attributable to processing difficulties that may be associated with ADHD, not to ADHD reported symptoms. Implications for assessment and intervention are discussed.  相似文献   
96.
In this paper, a method is proposed to reject disturbances in the model predictive control (MPC) strategy. In addition, uncertainties in the system parameters (i.e., internal disturbances) are considered as well. To achieve these goals, adaptive neural networks are designed as the predictor model and as the nonlinear disturbance observer, respectively. The disturbances are rejected via the optimization problem of the MPC. Stability of the closed-loop system is studied based on the Input-to-State Stability method. The proposed method is applied to the pH neutralization process and CSTR system and its effectiveness in optimal rejection of the disturbances and satisfying the system constrains is compared with the feed-forward control method.  相似文献   
97.
Cytochrome P450 2C9 (CYP2C9) is involved in metabolism of many important drugs and its genotype variations is thought to affect drug efficacy and the treatment process. The aim of this study was to assess the distribution of CYP2C9 allele and genotypic variants in Sistani ethnic group, living in Gorgan, South East of Caspian Sea and North East of Iran. This study included 140 Sistani, referred to the health center of Gorgan. CYP2C9 genotyping was carried out by polymerase chain reaction–restriction fragment length polymorphism technique. The allele frequency of CYP2C9*1, CYP2C9*2 and CYP2C9*3 was 76.1, 16.1 and 7.8%, respectively. The frequency of CYP2C9*1/*1, CYP2C9*1/*2, CYP2C9*1/*3, CYP2C9*2/*2, CYP2C9*2/*3 and CYP2C9*3/*3 genotypes was 53.9, 22.1, 11.4, 2.9, 4.3% and nil, respectively. In this study the genotypic variations of the CYP2C9 allele among the Sistani ethnic group was investigated and great differences were observed in comparison to other populations. Our findings suggest that different genotypes of CYP2C9 may influence the pharmacokinetics of some drugs. More studies on the pharmacokinetic effects of CYP2C9 genotypes may help physicians choose optimal dosage of some drugs for treatment and prevention of their side effects. Since different ethnic groups from all over the world use medications, it suggests to investigate the pharmacokinetic effects of CYP2C9 genotypes in different populations.  相似文献   
98.
This study examines the effect of the student teaching experience on preservice elementary teachers?? self-efficacy beliefs and the sources of their beliefs about technology integration in teaching in the UAE. The participants were 62 pre-service elementary teachers at the United Arab Emirates University. Pre- and post-survey was administered to examine participants?? self-efficacy beliefs for technology integration prior to and at the end of the teaching experience. Additionally, a purposeful subset of the sample (n?=?16) were interviewed based on their high self-efficacy belies to explore the sources of the high self-efficacy beliefs. Results showed a significant effect of student teaching experiences on participants?? judgment of their self-efficacy about technology integration. Mastery experience and vicarious experience reported to be the most influential sources of self-efficacy to integrate technology among preservice elementary teachers.  相似文献   
99.
This paper addresses the issue of how games can reshape education by describing current educational practices. It argues that there are conservative camps that emphasize structure and development of basic literacy and numeracy skills in education as well as liberal camps that emphasize immersion, and notices that both camps fail to train students able to address the crisis of innovation. A post-progressive pedagogy that integrates both structure and immersion to address this innovation crisis is described in the paper. It is also emphasized that epistemic games can serve as excellent tools at the hand of this post-progressive pedagogy.  相似文献   
100.
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