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This paper addresses a problem of optimal control design associated with the linear networked control systems (NCSs). We study a class of the conventional networked systems in the presence of time delays and propose a hybrid LQ-based theoretical and computational approach to the above NCSs. In particular, we develop an explicit theoretical representation of the networked control processes by an adequate auxiliary hybrid systems. For the constructive feedback control design procedure we derive the necessary hybrid Riccati-formalism and propose an implementable solution procedure. 相似文献
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This article examines how education unfolded as a science in Estonia in the period 1944–1991, i.e. from the second Soviet occupation to the fall of the USSR. Historical analysis of the way prominent scholars and institutions succeeded in overcoming the adverse conditions of that period is conducted by viewing their respective contributions through two theoretical lenses: cultural trauma theory to explore the adversities they had to contend with, and resilience theory to explain how those challenges were overcome. Through these means an account is constructed of how individuals and institutions succeeded in preserving the national Estonian and inter-war European legacy of educational philosophy, in the process confronting and countering adverse socio-cultural-political conditions. 相似文献
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Vadim Lvovich Deglin 《Infancia y Aprendizaje》2013,36(2):37-53
RESUMENUno de los rasgos característicos del cerebro humano consiste en la asimetría funcional de los hemisferios cerebrales. Existen gran cantidad de procedimientos para estudiar esta especialización hemisférica, pero aquí se propone un método basado en electrochoques unilaterales, de forma que se consiga que uno de los hemisferios quede inactivo. Así, un individuo que sólo tiene activo el hemisferio izquierdo conserva todos los aspectos que se refieren al pensamiento abstracto o conceptual y la comunicación puramente verbal. Hay, sin embargo, un deterioro en lo que concierne al pensamiento concreto, la imaginación y la prosodia. Lo contrario ocurre en un individuo que sólo tiene activado el hemisferio derecho.Las funciones del hemisferio izquierdo son las que han llevado a la humanidad al lugar actual en la escala de la evolución, aunque es necesaria la interacción complementaria de los dos hemisferios para una plena captación de la realidad. 相似文献
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Yazan M. Alsmadi Alaa M. Abdel-hamed Abo Eleyoun Ellissy Amged S. El-Wakeel Almoataz Y. Abdelaziz Vadim Utkin Ali Arshad Uppal 《Journal of The Franklin Institute》2019,356(8):4191-4214
This paper proposes an optimization scheme for optimal configuration and energy management of the micro-grid (MG), using the Cuckoo search optimization algorithm (CSOA). The selected MG supplies a load profile located between 30.119 latitude and 31.605 longitude. The energy produced by the MG generation sources, according to meteorological data of the proposed location, is calculated using MATLAB. The objective/fitness function is modeled and designed for minimizing the total investment cost (TIC) including capital, investment, operation and maintenance costs. A novel weighted goal attainment function (WGAF) has been proposed to reduce CO2 emissions and their associated costs. Moreover, WGAF also applies higher taxes on the amount of emissions that exceed governmental approved limits. To investigate the effects of WGAF on the TIC ($/year), annual cost of energy ($/kWh), and CO2 emissions, various weighted coefficients are analyzed. The simulation results have shown that the designed optimization scheme can robustly and efficiently produce the optimal MG configuration that is both eco-friendly and generates economic benefits. 相似文献
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Hannu Räty Katri Komulainen Tuuli Paajanen Mia Markkanen Nina Skorokhodova Vadim Kolesnikov 《Educational studies》2012,38(5):573-586
This study sets out to examine Finnish and Russian children’s representations of intellectual competence as contextualised in the hierarchies of abilities, age and gender. Finnish and Russian pupils, aged 11–12?years, were asked to draw pictures of an intelligent person and an ordinary person. It was found that gender appearance of intelligent men and women was less heterosexual than that of ordinary men and women. In Russian pictures, the intelligent characters, especially women, were widely separated from the ordinary ones in terms of cognitive-mental features. In Finnish depictions, the differentiation between the intelligent and ordinary characters, especially women, was not so categorical and was primarily based on status. It appears that Russian children are apt to relate their representations of intellectual ability to the institutionalised systems of cognitive competence, education and science, whereas Finnish children associate intelligence to social success as well. Further, cultural and gender-related hierarchies of age seemed to reflect in the children’s images. 相似文献
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Sliding mode control algorithms for buck and boost power converters are surveyed in the paper. Current and voltage controls are demonstrated for the both cases. It is shown, that direct voltage control for a boost converter results in unstable zero dynamics. Chattering suppression based on harmonic cancellation principle along with switching frequency control is demonstrated. 相似文献
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Vadim Azhmyakov 《Journal of The Franklin Institute》2012,349(4):1323-1336
This paper is devoted to a theoretic framework for a general optimal control problem (OCP) associated with the classic sliding mode process. The sliding dynamic behavior is interpreted here as a special kind of additional constraints related to the main optimization problem. We are specially interested in the development of some adequate constructive approximations of the original OCPs. The mathematical approach based on the set-valued analysis allows to study the discontinuity of sliding mode dynamics in the abstract setting. Moreover, we also establish some sensitivity properties of the optimal solutions. The obtained results provide an universal analytical tool for the corresponding conceptual approximation schemes related to the original OCPs. The constructive approximations proposed in this paper are numerically stable and can be applied to various classes of optimal control processes governed by the affine control systems. 相似文献
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In different areas of engineering, mathematical models are used to describe real life phenomena and experiments are conducted to validate them. It is common that these models may contain a number of parameters that cannot be measured directly or calculated. Thus, parameter estimation is an important step in the process of modeling based on empirical data of the system.In the control system’s literature, one can find considerable amount of research in the area of system parameters identification. Most of these techniques are based on minimizing the estimation error in some statistical framework such as least square error based methods. In most cases, using these techniques, one can prove the uniform exponential stability of the state and parameter estimation error, but the convergence rate can be too low. However, when designing control systems, knowledge of unknown immeasurable (or even time varying) parameters might be crucial for the operation of the controller and thus have to be accurately estimated with a desired rate of convergence. In this paper, we demonstrate a way to provide an estimation technique with tunable convergence rate using sliding mode with linear operators such as time delay. 相似文献