检索结果-内蒙古大学图书馆

Conditions for convergence of solutions in the computation of optimal controls

IMA Journal of Applied Mathematics (Institute of Mathematics and Its Applications) 1978年第1期22卷 1-14页

作者： Stassinopoulos, G.I. Vinter, R.B. Department of Computing and Control Imperial College of Science and Technology London United Kingdom

This paper gives conditions under which algorithms possessing a certain descent property generate sequences which are convergent with limit points which are relaxed controls satisfying first-order conditions of optimality. Conditions are also given under which the sequence possesses accumulation points in the class of ordinary controls w.r.t. the L^p norm. Examples illustrate the applicability of the results. © 1978, by Academic Press Inc. (London) Ltd.

关键词： Converge arithmetic Sequences Optimal control Solutions Standing Orders algorithms cluster point

来源：评论

学校读者我要写书评

暂无评论

Diameter of back-up rolls in a 4-high rolling stand

引用

Metals Technology 1975年第1期2卷 532-534页

作者： Spooner, P.D. Smyth, R.M. Department of Computing and Control Imperial College of Science and Technology United Kingdom

The purpose of back-up rolls in a 4-high rolling-mill stand is to provide lateral stiffness to the work rolls to reduce bending and thereby minimize strip shape and profile defects. The maximum and minimum diameters of the work rolls are limited by considerations of roll force and roll wear. However, similar criteria are not availablefor determining the choice of back-up roll diameters. The effect of changing back-up roll diameter on strip shape and related parameters, with the aim of defining a range of possible diameters for any specific mill, is investigated. © 1975 Maney Publishing.

关键词：

来源：评论

学校读者我要写书评

暂无评论

The use of the Ada language for programming a distributed system

引用

Annual Review in Automatic Programming 1980年第C期10卷 39-44页

作者： Downes, V.A Goldsack, S.J Department of Computing and Control Imperial College of Science and Technology London United Kingdom

This paper discusses the programming of networks of co-operating computers in a control environment. The computers in the systems considered are weakly coupled, having no shared store and communicating by messages over a network. Such a system could be programmed in Ada, or any other language, as a set of separate machines, with the communication explicitly handled by input/output procedures. However, this would not be in the spirit of a distributed system, involving a very rigid structure, decided when the program was written. A system for control should preferably be written as a complete program, in a uniform language, regarding the manner in which it is executed, in a single machine or in a network of smaller machines, as an implementation detail. Being designed for the programming of embedded systems, Ada has many features which are appropriate for this purpose. There do seem, however, to be a number of areas where work is needed to resolve difficulties which will arise in practice. This paper attempts to identify these problem areas and offer possible solutions to some of them. It is suggested that it is useful to recognize a logical module for such programs which encapsulates groups of tasks which it is necessary to confine to a single processor node, due to timing or resource sharing constraints. These modules can be programmed in Ada as tasks, nevertheless they represent a sufficiently distinct abstraction to deserve separate nomendature;here they are referred to as zones. © 1982.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A feasible direction algorithm for convex optimization: Global convergence rates

引用

Journal of Optimization Theory and Applications 1980年第1期30卷 1-18页

作者： Allwright, J.C. Department of Computing and Control Imperial College of Science and Technology London United Kingdom

At each iteration, the algorithm determines a feasible descent direction by minimizing a linear or quadratic approximation to the cost on the feasible set. The algorithm is easy to implement if the approximation is easy to minimize on the feasible set, which happens in some important cases. Convergence rate information is obtained, which is sufficient to enable deduction of the number of iterations needed to achieve a specified reduction in the distance from the optimum (measured in terms of the cost). Existing convergence rates for algorithms for solving such convex problems are either asymptotic (and so do not enable the required number of iterations to be deduced) or decrease as the number of constraints increases. The convergence rate information obtained here, however, is independent of the number of constraints. For the case where the quadratic approximation to the cost is not strictly convex (which includes the linear approximation case), the diameter is the only property of the feasible set which affects the convergence rate information. If the quadratic approximation is strictly convex, the convergence rate is independent of the size and geometry of the feasible set. An application to a control-constrained optimal control problem is outlined. © 1980 Plenum Publishing Corporation.

关键词： convergence rates for optimization algorithms Convex programming feasible direction algorithms

来源：评论

学校读者我要写书评

暂无评论

Stabilizability and semigroups with discrete generators

引用

IMA Journal of Applied Mathematics (Institute of Mathematics and Its Applications) 1977年第3期20卷 371-378页

作者： Vinter, R.B. Department of Computing and Control Imperial College of Science and Technology London United Kingdom

A number of semigroups of bounded linear transformations on a Banach space of importance in applications have the property that the infinitesimal generator is "discrete". For evolution equations defined through such semigroups, it is often possible to give simple criteria for stabilizability (and detectability). Such criteria are important in the study of certain control and filtering problems. © 1977 Academic Press Inc. (London) Limited.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A language‐independent system to aid the development of structured programs

引用

Software: Practice and Experience 1976年第4期6卷 487-503页

作者： Cunningham, R.J. Pugh, C.G. Department of Computing and Control Imperial College of Science and Technology London United Kingdom

The GLIDE system is an effectively language‐independent aid of modest proportions for developing programs by stepwise refinement. The basis of the system is a suitable program file environment The system has been implemented on the Imperial College Computer Centre control Data machine and is currently available for the development of programs written in PASCAL, ALGOL, FORTRAN, SIMULA and JCL (Job control Language). The program itself is written in PASCAL The facilities obtained within the scope and limitations of the system conception suggest that this type of system could be given further attention. Copyright © 1976 John Wiley & Sons, Ltd

关键词： Software development aid Structured programming

来源：评论

学校读者我要写书评

暂无评论

Production of exotic hadrons in pp and nuclear collisions

引用

Nuclear Science and Techniques 2025年第4期36卷 1-22页

作者： Jin-Hui Chen Feng-Kun Guo Yu-Gang Ma Cheng-Ping Shen Qi-Ye Shou Qian Wang Jia-Jun Wu Bing-Song Zou Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Key Laboratory of Atomic and Subatomic Structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China Department of Physics Tsinghua UniversityBeijing 100084China

Exotic hadrons,beyond the conventional quark model,have been discovered over the past two *** these states can lead to a deeper understanding of the nonperturbative dynamics of the strong *** this review,we focus on the production of exotic hadrons in pp,PP^(-),and nuclear *** observations of light and hypernuclei as prototypes of hadronic molecules in heavy-ion collisions are also briefly discussed.

关键词： Exotic hadrons Hadron-hadron collision Heavy-ion collision

来源：评论

学校读者我要写书评

暂无评论

Towards Energy-Efficiency: Integrating MATD3 Reinforcement Learning Method for Computational Offloading in RIS-Aided UAV-MEC Environments

引用

IEEE Internet of Things Journal 2025年

作者： Wu, Liangshun Zhang, Cong Zhang, Bin Du, Jianbo Qu, Junsuo Key Laboratory of Embedded System and Service Computing Tongji University Ministry of Education Shanghai201804 China Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai201210 China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai200240 China Xi'an Key Laboratory of Advanced Control and Intelligent Process School of Automation Xi'an University of Posts & Telecommunications Xi'an710061 China Xinjiang University of Political Science and Law Tumushuke832003 China School of Remote Sensing and Information Engineering Wuhan University Wuhan430079 China Department of Computer City University of Hong Kong 999077 Hong Kong School of Communications and Information Engineering Xi'an University of Posts & Telecommunications Xi'an710061 China

With the proliferation of IoT devices, there is an escalating demand for enhanced computing and communication capabilities. Mobile Edge computing (MEC) addresses this need by relocating computing resources to the network edge, thereby delivering swifter and more efficient services. This paper introduces a computation offloading and energy consumption optimization framework that leverages Reconfigurable Intelligent Surfaces (RIS), Unmanned Aerial Vehicles (UAVs), and MEC. The scheme aims to maximize energy efficiency through the optimization of task allocation, RIS phase shifts, and UAV trajectories. By employing the Multi-Agent Twin Delayed Deep Deterministic Policy Gradient (MATD3) reinforcement learning algorithm, the paper further refines UAV trajectories and RIS configurations. The simulation results indicate that the proposed method surpasses the traditional Concave-Convex Procedure (CCCP) algorithm in both UAV trajectory control and RIS configuration, demonstrating quicker convergence and enhanced stability. The method proves to be adaptable to diverse environments and tasks, showcasing notable benefits in RIS-assisted interference suppression, particularly with large RIS, thereby enhancing UAV data reception rates. Additionally, MATD3 exhibits faster and smoother convergence for extended task durations and smaller RIS scenarios. Simulation results reveal that UAVs tend to move closer to RIS, with energy efficiency falling as IoT tasks increase, affirming the proposed algorithm's high energy efficiency and effectiveness. © 2025 IEEE.

关键词： Unmanned aerial vehicles (UAV)

来源：评论

学校读者我要写书评

暂无评论

COMPUTER-AIDED MECHANICAL ENGINEERING - 1958 TO 1988

引用

COMPUTER-AIDED DESIGN 1989年第5期21卷 274-288页

作者： ELLIOTT, WS Department of Computing and Control Imperial College of Science and Technology 180 Queens Gate London SW7 8BP UK

A review of the development of CAD, seen from a mechanical engineering and UK perspective, is presented. Thirty years of work on various aspects of CAD are discussed and the origins of some commercial packages such as... 详细信息

关键词： mechanical CAE CADCAM history

来源：评论

学校读者我要写书评

暂无评论

A framework for load frequency regulation in multi-area grid-connected hybrid power systems with plug-in electric vehicles

引用

Renewable Energy Focus 2025年 54卷

作者： Gulzar, Muhammad Majid Jameel, Ahlam Habib, Salman Arishi, Ali Irfan, Rasmia Ahmad, Hasnain Tehreem, Huma Department of Control & Instrumentation Engineering King Fahd University of Petroleum & Minerals Dhahran31261 Saudi Arabia King Fahd University of Petroleum & Minerals Dhahran31261 Saudi Arabia Department of Electrical Engineering Lahore College for Women University Lahore54000 Pakistan King Fahd University of Petroleum & Minerals Dhahran31261 Saudi Arabia Department of Industrial Engineering King Khalid University Abha61421 Saudi Arabia Institute of Electrical Electronics and Computer Engineering University of the Punjab Lahore54000 Pakistan Islamabad45650 Pakistan School of Computing Engineering & Digital Technologies Teesside University Middlesbrough Campus TS1 3BX United Kingdom

Due to technological advancements, the rapid expansion of renewable energy in the power sector has led to challenges with operation, security, and management. Reduced grid inertia necessitates maintaining normal operating frequency and lowering tie-line power changes to assure stability and reliability. In this article, a framework for load frequency controller (LFC) that is based on the combinations of traditional controllers is proposed. In this study, the filtered derivative proportional controller cascaded with β proportional integral, abbreviated as PDF+(β+PI), is suggested for LFC applications. In addition, the optimization of the proposed controller parameters for two-area power grids is tuned using the grasshopper optimization algorithm (GOA). The contribution of aggregated model for electric vehicles (EVs) is also taken into consideration. The performance of the proposed controller is evaluated with the effectiveness of other controllers like cascaded proportional integral and derivative (PI-PD), 1 plus proportional integral derivative (1+PID), 1 plus proportional integral (1+PI), and fractional order proportional integral derivative (FOPID). The proposed GOA optimizer tuned PDF+(β+PI) controller is tested for reliability against variations in load, penetration of renewable energy sources, and parametric uncertainties of the grid for the time integral absolute error (ITAE) objective function. By employing the proposed controller, the system achieves rapid and efficient minimization of the objective function. Thus, the controller is highly suitable for applications requiring quick response and precise performance. © 2025 Elsevier Ltd

关键词： Two term control systems

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：