检索结果-南通市图书馆

PID Controller Optim.zation by GA and Its Perform.nces on the Electro-hydraulic Servo Control System

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2008年第4期21卷 378-384页

作者： Karam.m. Elbayom. School of Autom.tion Science and Electrical Engineering Beijing University of Aeronautics and Astronautics

A proportional integral derivative （PID） controller is designed and attached to electro-hydraulic servo actuator system.（EHSAS） to control the angular position of the rotary actuator which control the m.vable surface of space vehicles. The PID gain param.ters are optim.zed by the genetic algorithm.（GA）. The controller is verified on the new state-space m.del of servo-valves attached to the physical rotary actuator by SIm.LINK program. The controller and the state-space m.del are verified experim.ntally. Sim.lation and experim.ntal results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as com.ared with the classical PID controller and the com.ensator controller.

关键词： PID controller electro-hydraulic servo control system genetic controller GA

A REm.RK ON THE REGULARITY OF VECTOR-VALUED m.PPINGS DEPENDING ON TWO VARIABLES WHICH m.NIm.ZE SPLITTING-TYPE VARIATIONAL INTEGRALS

在线全文

学校读者我要写书评

暂无评论

Acta m.them.tica Scientia 2010年第3期30卷 963-967页

作者： m. Bildhauer m. Fuchs Universitt des Saarlandes Fachbereich 6.1 Mathematik

We com.ine the m.xim.m.principle for vector-valued m.ppings established by D＇Ottavio, Leonetti and m.sciano [7] with regularity results from.[5] and prove the Holder continuity of the first derivatives for local m.ni... 详细信息

关键词： Local m.nim.zers interior regularity anisotropic energies two-dim.nsional problem.

VIEWING URBAN DISRUPTIONS FROm.A DECISION INFORm.TICS PERSPECTIVE

在线全文

学校读者我要写书评

暂无评论

Journal of System. Science and System. Engineering 2005年第3期14卷 257-288页

作者： Jam.s m. TIEN Rensselaer Polytechnic Institute Troy New York USA

Urban infrastructures are the focus of terrorist acts because, quite sim.ly, they produce the m.st visible im.act, if not casualties. While terrorist acts are the m.st insidious and onerous of all disruptions, it is obvious that there are m.ny sim.larities to the way one should deal with these willful acts and those caused by natural and accidental incidents that have also resulted in adverse and severe consequences. However, there is one m.jor and critical difference between terrorist acts and the other types of disruptions： the terrorist acts are willful - and therefore also adaptive, if not coordinated. One m.st counter these acts with the sam., if not m.re sophisticated, willful, adaptive and inform.d approach. Real-tim., inform.tion-based decision m.king - which Tien （2003） has called the decision inform.tics paradigm.- is the approach advanced herein to help m.ke the right decisions at the various stages of a disruption. It is focused on decisions and based on m.ltiple data sources, data fusion and analysis m.thods, tim.ly inform.tion, stochastic decision m.dels and a system. engineering outlook; m.reover, it is m.ltidisciplinary, evolutionary and system.c in practice. The approach provides a consistent way to address real-tim. em.rgency issues, including those concerned with the preparation for a m.jor disruption, the prediction of such a disruption, the prevention or m.tigation of the disruption, the detection of the disruption, the response to the disruption, and the recovery steps that are necessary to adequately, if not fully, recuperate from.the disruption. The efforts of the U. S. Departm.nt of Hom.land Security and its academ.cally-based Hom.land Security Centers of Excellence are considered within the proposed types, stages and decisions fram.work.

关键词： Data fusion data analysis adaptive algorithm. decision m.deling system. engineering

THE SPUTNIK OF SERVGOODS： AUTONOm.US VEHICLES

在线全文

学校读者我要写书评

暂无评论

Journal of System. Science and System. Engineering 2017年第2期26卷 133-162页

作者： Jam.s m. Tien College of Engineering University of Miami Coral Gables Florida 33146 USA

In an earlier paper （Tien 2015）, the author defm.d the concept of a servgood, which can be thought of as a physical good or product enveloped by a services-oriented layer that m.kes the good sm.rter or m.re adaptable and custom.zable for a particular use. Adding another layer of physical sensors could then enhance its sm.rtness and intelligence, especially if it were to be connected with each other or with other servgoods through the Internet of Things. Such sensed servgoods are becom.ng the products of the future. Indeed, autonom.us vehicles can be considered the exem.lar servgoods of the future; it is about decision inform.tics and em.races the advanced technologies of sensing （i.e., Big Data）, processing （i.e., real-tim. analytics）, reacting （i.e., real-tim. decision-m.king）, and learning （i.e., deep learning）. Since autonom.us vehicles constitute a huge quality-of-life disruption, it is also critical to consider its policy im.act on privacy and security, regulations and standards, and liability and insurance. Finally, just as the Soviet Union inaugurated the space age on October 4, 1957, with the launch of Sputnik, the first m.n-m.de object to orbit the Earth, the U. S. has inaugurated an age of autom.ta or autonom.us vehicles that can be considered to be the U. S. Sputnik of servgoods, with the full support of the U. S. governm.nt, the U. S. auto industry, the U. S. electronic industry, and the U.S. higher educational enterprise.

关键词： Autonom.us vehicles goods services servgoods sensors Internet of Things decisioninform.tics Big Data real-tim. analytics cloud com.uting deep learning privacy security regulations,standards liability insurance Sputnik

Finite Elem.nt Analysis of Residual Stress and Distortion in an Eccentric Ring Induced by Quenching

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料热处理学报 2004年第05B期25卷 746-751页

作者： LI m. Victor Portland State University PO Box 751-ME Portland OR 97207-075J USA

The residual stresses and distortion induced by quenching in an eccentric ring were investigated in this study with finite elem.nt m.thod. The ring was m.de of AISI 52100 steel. A fully coupled 3D tem.erature-displacem.nt analysis was perform.d to sim.late heat transfer, phase transform.tions, and m.chanical stresses and strains during the heating and subsequent quenching processes. Com.ercial FEA package ABAQUS/Standard 6.4 was used for the analyses along with user subroutines developed by the authors to m.del the therm.l and m.chanical constitutive behavior. The sim.lation results show that transform.tion plasticity plays an im.ortant role on the residual stress distribution.

关键词：残余应力有限元分析变形偏心环相变塑性

Variable fluid properties and variable heat flux effects on the flow and heat transfer in a non-Newtonian m.xwell fluid over an unsteady stretching sheet with slip velocity

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第9期22卷 480-485页

作者： Ahm.d m. m.gahed Departm.nt of m.them.tics Faculty of ScienceBenha University

The effects of variable fluid properties and variable heat flux on the flow and heat transfer of a non-Newtonian m.xwell fluid over an unsteady stretching sheet in the presence of slip velocity have been studied. The governing differential equations are transform.d into a set of coupled non-linear ordinary differential equations and then solved with a num.rical technique using appropriate boundary conditions for various physical param.ters. The num.rical solution for the governing non-linear boundary value problem.is based on applying the fourth-order Runge-Kutta m.thod coupled with the shooting technique over the entire range of physical param.ters. The effects of various param.ters like the viscosity param.ter, therm.l conductivity param.ter, unsteadiness param.ter, slip velocity param.ter, the Deborah num.er, and the Prandtl num.er on the flow and tem.erature profiles as well as on the local skin-friction coefficient and the local Nusselt num.er are presented and discussed. Com.arison of num.rical results is m.de with the earlier published results under lim.ting cases.

关键词： m.xwell fluid unsteady stretching sheet variable fluid properties variable heat flux

ROBUST OUTPUT FEEDBACK STABILIZATION OF NONLINEAR NETWORKED SYSTEm. VIA A FINITE DATA-RATE COm.UNICATION CHANNEL

在线全文

学校读者我要写书评

暂无评论

Journal of System. Science & Com.lexity 2011年第1期24卷 1-13页

作者： Teddy m. CHENG School of Electrical Engineering and Telecom.unications the University of New South Wales Sydney NSW 2052 Australia

This paper addresses a robust stabilization problem.of a class of uncertain nonlinear system. using output m.asurem.nts via a finite data-rate com.unication channel. The authors assum.s that there exist an observer and a control law for the system. in the absence of any finite data-rate com.uni- cation channel. Based on the observer and the control law, the authors constructs an encoder/decoder pair and provides a sufficient condition, including suitable sam.ling period and data rate, which will guarantee the stability of the closed-loop system. when a finite data-rate com.unication channel is introduced.

关键词： Control over com.unication networks nonlinear control output feedback uncertain system..

Novel delay-dependent stability analysis of Takagi-Sugeno fuzzy uncertain neural networks with tim. varying delays

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第7期21卷 49-60页

作者： m. Syed Ali Departm.nt of m.them.tics Thiruvalluvar University

This paper presents the stability analysis for a class of neural networks with tim. varying delays that are represented by the Takagi^ugeno IT-S） m.del. The m.in results given here focus on the stability criteria using a new Lyapunov functional. New relaxed conditions and new linear m.trix inequality-based designs are proposed that outperform.the previous results found in the literature. Num.rical exam.les are provided to show that the achieved conditions are less conservative than the existing ones in the literature.

关键词： neutral neural networks linear m.trix inequality Lyapunov stability tim. varying delays

A survey of RDF data m.nagem.nt system.

在线全文

学校读者我要写书评

暂无评论

Frontiers of Com.uter Science 2016年第3期10卷 418-432页

作者： m. Tam.r OZSU Cheriton School of Com.uter Science University of Waterloo Waterloo N2L 3G1 Canada

RDF is increasingly being used to encode data for the sem.ntic web and data exchange. There have been a large num.er of works that address RDF data m.nage- m.nt following different approaches. In this paper we pro- vide an overview of these works. This review considers cen- tralized solutions （what are referred to as warehousing ap- proaches）, distributed solutions, and the techniques that have been developed for querying linked data. In each category, further classifications are provided that would assist readers in understanding the identifying characteristics of different approaches.

关键词： RDF SPARQL linked object data.