检索结果-内蒙古大学图书馆

A Hybrid Multiobjective Differential Evolution Algorithm and Its Application to the Optimization of Grinding and Classification

引用

JOURNAL OF APPLIED MATHEMATICS 2013年第unknown期2013卷 1-15页

作者： Wang, Yalin Chen, Xiaofang Gui, Weihua Yang, Chunhua Caccetta, Lou Xu, Honglei Cent S Univ Sch Informat Sci & Engn Changsha 410083 Peoples R China Curtin Univ Dept Math & Stat Perth WA 6845 Australia

The grinding-classification is the prerequisite process for full recovery of the nonrenewable minerals with both production quality and quantity objectives concerned. Its natural formulation is a constrained multiobjective optimization problem of complex expression since the process is composed of one grinding machine and two classification machines. In this paper, a hybrid differential evolution (DE) algorithm with multi-population is proposed. Some infeasible solutions with better performance are allowed to be saved, and they participate randomly in the evolution. In order to exploit the meaningful infeasible solutions, a functionally partitioned multi-population mechanism is designed to find an optimal solution from all possible directions. Meanwhile, a simplex method for local search is inserted into the evolution process to enhance the searching strategy in the optimization process. Simulation results from the test of some benchmark problems indicate that the proposed algorithm tends to converge quickly and effectively to the Pareto frontier with better distribution. Finally, the proposed algorithm is applied to solve a multiobjective optimization model of a grinding and classification process. Based on the technique for order performance by similarity to ideal solution (TOPSIS), the satisfactory solution is obtained by using a decision-making method for multiple attributes.

关键词： HYBRID systems DIFFERENTIAL evolution (computer science) computer algorithms CLASSIFICATION COMBINATORIAL optimization DISTRIBUTION (Probability theory) STOCHASTIC convergence

来源：评论

学校读者我要写书评

暂无评论

algorithms Unlocked 1

引用

丛书名： MIT Press

2013年

作者： [美] Thomas H·Cormen

ISBN: (纸本)9780262518802

Have you ever wondered how your GPS can find the fastest way to your destination, selecting one route from seemingly countless possibilities in mere seconds? How your credit card account number is protected when you make a purchase over the Internet? The answer is algorithms. And how do these mathematical formulations translate themselves into your GPS, your laptop, or your smart phone? This book offers an engagingly written guide to the basics of computer algorithms. In algorithms Unlocked, Thomas Cormen -- coauthor of the leading college textbook on the subject -- provides a general explanation, with limited mathematics, of how algorithms enable computers to solve problems. Readers will learn what computer algorithms are, how to describe them, and how to evaluate them. They will discover simple ways to search for information in a computer; methods for rearranging information in a computer into a prescribed order ("sorting"); how to solve basic problems that can be modeled in a computer with a mathematical structure called a "graph" (useful for modeling road networks, dependencies among tasks, and financial relationships); how to solve problems that ask questions about strings of characters such as DNA structures; the basic principles behind cryptography; fundamentals of data compression; and even that there are some problems that no one has figured out how to solve on a computer in a reasonable amount of time.

关键词： computer algorithms

来源：评论

学校读者我要写书评

暂无评论

Energy-efficient control of an air handling unit for a single-zone VAV system

Energy-efficient control of an air handling unit for a singl...

引用

IEEE Annual Conference on Decision and Control

作者： Siddharth Goyal Prabir Barooah Department of Mechanical and Aerospace Engineering University of Florida Gainesville Florida USA

ISBN: (纸本)9781467357159

A large fraction of energy consumed by the HVAC (heating ventilation and air-conditioning) system in a commercial building is consumed at the AHUs (air handling units) that condition a mixture of outside and return air to specific temperature and humidity levels. Traditionally, the return air ratio and temperature of the air leaving the cooling coils in the AHU (conditioned air temperature) are maintained at pre-determined set points instead of being based on real-time measurements of occupancy, zone humidity, and outside weather. In this paper, we investigate the potential of energy savings as a function of the complexity of control algorithm. The inputs that can be commanded by the controllers are: air flow rate, return air ratio, conditioned air temperature, and the temperature of air leaving the heating coils in the AHU. Simulation results show that the controllers that use the measurements of occupancy, zone humidity, and outside weather result in significant savings over conventional controllers that do not use such measurements, without sacrificing thermal comfort or indoor air quality (IAQ). Surprisingly, a simple feedback control scheme is found to perform almost as well as a much more complex MPC (model predictive control) controller.

关键词： air handling units return air air temperature Controllers computer algorithms energy saving Heating coils condition of air Cooling coils AIR CONTROLLING commercial buildings Temperature Weather air Energy efficiency

来源：评论

学校读者我要写书评

暂无评论

Taking a break from chemotherapy to fight drug-resistance: The cases of Cancer and HIV/AIDS

Taking a break from chemotherapy to fight drug-resistance: T...

引用

Annual International Conference of the IEEE Engineering in Medicine and Biology Society

作者： Marios M. Hadjiandreou Georgios D. Mitsis Department of Electrical and Computer Engineering University of Cyprus

ISBN: (纸本)9781457702150

In this work, we present how optimized treatment interruptions during chemotherapy may be used to control drug-resistance, a major challenge for clinicians worldwide. Specifically, we examine resistance in cancer and HIV/AIDS. For each disease, we use mathematical models alongside real data to represent the respective complex biological phenomena and optimal control algorithms to design optimized treatment schedules aiming at controlling disease progression and patient death. In both diseases, it is shown that the key to controlling resistance is the optimal management of the frequency and magnitude of treatment interruptions as a way to facilitate the interplay between the competitive resistant/sensitive strains.

关键词： Drug Therapy Cancer Cancer treatment interruption Antineoplastic Agents computer algorithms maladjustment fight Respite Care Disease Progression observational data Mathematical Model Biological Phenomena

来源：评论

学校读者我要写书评

暂无评论

Automatic Resonant Frequency Tracking in Unregulated LLC Resonant Converters Based on Total Resonant Current Harmonic Calculation

Automatic Resonant Frequency Tracking in Unregulated LLC Res...

引用

IEEE Energy Conversion Congress and Exposition

作者： Siyao Jiang Weimin Zhang Bo Liu Fred Wang School of Information Science and Engineering Shandong University Jinan China Department of Electrical Engineering and Computer Science The University of Tennessee Knoxville USA

ISBN: (纸本)9781479903375

The desired working condition for the unregulated LLC resonant converter is to have the switching frequency equal to the resonant frequency in order to achieve higher efficiency. However, since the converter works in open-loop condition, the switching frequency usually deviates from the resonant frequency in real converter prototype. In this paper, a novel switching frequency control scheme to track the resonant frequency is proposed. Theoretically, the primary side current of LLC resonant converter is a pure sinusoidal waveform when it works at resonant frequency. The proposed control algorithm is based on tracking the minimum value of the total resonant current harmonic to realize the switching frequency tracking the resonant frequency. A closed-loop digital controller is presented to calculate the total resonant current harmonic to estimate the shape of the waveform. The switching frequency can be well controlled to track the resonant frequency. As a result, the higher efficiency can be achieved.

关键词： resonant frequencies resonant converter Switching frequency Converters digital controller minimum value computer algorithms

来源：评论

学校读者我要写书评

暂无评论

MPC for Reducing Energy Storage Requirement of Wind Power Systems

MPC for Reducing Energy Storage Requirement of Wind Power Sy...

引用

American Control Conference

作者： Chiao-Ting Li Huei Peng Jing Sun Department of Mechanical Engineering University of Michigan Department of Naval Architecture and Marine Engineering University of Michigan

ISBN: (纸本)9781479901777

This paper discusses using the battery energy storage system (BESS) to mitigate wind power intermittency, so that wind power can be dispatchable on an hourly basis like fossil fuel power plants. In particular, model predictive control (MPC) is used to control the charge and discharge of BESS to compensate for wind power forecast errors and minimize operation costs to the wind farm owner. A ramp rate penalty on wind power scheduling is included in the optimization to make the optimal control trajectory smoother, while the performance is kept intact. Numerical simulations with a one-year long wind power dataset show that MPC controller is much more effective in reducing the operation cost to the wind farm owner than the heuristic control algorithm or conventional reserves, in that BESS with a much smaller capacity will be suffice to achieve the same cost reduction.

关键词： Wind energy Fossil fueled power plants Wind farms wind power system battery energy storage system COST REDUCTION computer algorithms Wind

来源：评论

学校读者我要写书评

暂无评论

A Novel Time Optimal Path Following Controller with Bounded Velocities for Mobile Robots with Independently Steerable Wheels

A Novel Time Optimal Path Following Controller with Bounded ...

引用

IEEE/RSJ International Conference on Intelligent Robots and Systems

作者： Reza Oftadeh Reza Ghabcheloo Jouni Mattila Intelligent Hydraulics and Automation Department Tampere University of Technology 33101 Finland

ISBN: (纸本)9781467363563

Mobile robots with independently steerable wheels possess many high maneuverability features of omnidirectional robots while benefiting from better performance and capability of moving on rough terrains. However, motion control of such robots is a challenging task due to presence of singular configurations and unboundedly large steering velocities in the neighborhood of those singularities. Many proposed approaches rely on numerical solutions that keep the robot out of bulky regions around the singular points and hence lose some of the robot maneuverability. Based on a class of traditional path followers we design a new globally stable path following controller that exploits the high maneuverability of the platform. This design allows us to derive a set of closed-form analytical functions that describe the robot base velocity as a function of the wheels driving and steering velocities while abide to the robot non-holonomic constraints. Those functions are then utilized to find the maximum instantaneous velocity of the body that keeps the wheels velocities under the pre-specified bounds no matter how much the robot gets close or far from its singular configurations. The control algorithms developed in this paper have been evaluated on iMoro, a four wheel independently steered mobile manipulator designed and developed at IHA/TUT. Experimental data is also shown that show efficacy of the method.

关键词： Mobile robots Wheels Controllers Robot maneuverability Mobile manipulator Time optimal computer algorithms Motor Control

来源：评论

学校读者我要写书评

暂无评论

Artificial force in robust control of mobile manipulator application

Artificial force in robust control of mobile manipulator app...

引用

Workshop on Robot Motion and Control

作者： Alicja Mazur Mateusz Cholewinski Institute of Computer Engineering Control and Robotics Wroclaw University of Technology

ISBN: (纸本)9781467355094

In the paper mobile manipulator using skid steering platform, has been considered. Such system is underactuated. This paper presents the concept of artificial force applied in robust control an discussion of obtained results. Artificial force concept assumes full rank of input matrix, describing relationships between controlled variables and number of actuators. Despite of assumption that the additional actuator signal is identically equal to zero, the invertibility of the input matrix is achieved. This signal is used to generate reference signal, needed in control algorithm. Mathematical proof of proper action of such a control law has been presented using Lyapunov-like function. Usefulness of this concept, under the assumption of parametric uncertainty of the terrain as well as in order to track inadmissible trajectories, has been verified in numerous simulations.

关键词： Robust control Mobile manipulator control law full rank actuators Reversibility Force Reference signals computer algorithms terrains

来源：评论

学校读者我要写书评

暂无评论

Improved Steady State and Transient Behavior of Static Power Converters by Means of an Operating Mode Identifier Algorithm

Improved Steady State and Transient Behavior of Static Power...

引用

Annual Conference of the IEEE Industrial Electronics Society

作者： E. Maurelia J. Espinoza R. Ramirez M. Reyes P. Melin Cesar A. Silva Javier Munoz Electrical Engineer Department Concepcion University Electronic Engineer Department Santa Maria University Department of Industrial Technologies Universidad de Talca

ISBN: (纸本)9781479902255

Nowadays Finite-Control-Set Model Predictive Control (FCS-MPC) is being successfully used in static power converters. The algorithm requires defining a functional in order to optimize it and thus find the best switch combination. So far the functional optimizes either the steady state or the transient operation. In fact, for steady state operation, the minimization of the switching frequency as well as high quality waveforms are the basic objectives. Contrary, during transient conditions the settling time minimization is usually used as a basic objective. This work presents an algorithm that is able to detect if the system is either under steady state or transient operating mode and applies the appropriate control algorithm. Hence, both operating modes are controlled under optimum conditions. Simulated results show the performance of the proposed control scheme.

关键词： Current control Transient identification Steady state identification Predictive control Predictive control Current control Transient performance Static power converters operation mode Steady state power conversion unit Economic Resources TRANSIENT OPERATION computer algorithms algorithms

来源：评论

学校读者我要写书评

暂无评论

Priority and Buffer Based Admission Control in Relay-enhanced LTE-A systems

Priority and Buffer Based Admission Control in Relay-enhance...

引用

European Wireless 2013;19th European Wireless Conference

作者： Fasil Tesema Fabrizio Granelli Federica Vitiello Simone Redana University of Trento Nokia Siemens Networks St.

Relay Nodes (RNs) introduction is one of the main features of LTE-Advanced (LTE-A) with the aim of enhancing network coverage and capacity at cell-edge. However, a proper admission control scheme is required to increase the total number of admitted users in the system. This work proposes the implementation and evaluation of three types of admission control schemes taking into account the optimal resource partitioning between RNs and DeNB. The first scheme bases the admission and rejection of users on the resources' availability. The second scheme adds an admission control algorithm based on users' priorities. Finally, the third scheme introduces a dynamic buffer in order to utilize the free resources during the empty arrival periods and to further improve the performance. Performance analysis of the proposed admission control algorithms for different download bit rates and file size is performed through simulations. The optimal buffer configuration that minimizes the probability of unhappy users is determined.

关键词： Relay LTE-Advanced Admission Control Relay Node Admission control Trunk Node relay computer algorithms Long Term Evolution Consumers File Size precedence

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：