检索结果-内蒙古大学图书馆

Generic Optimal Temperature Profiles for a Class of Jacketed Tubular Reactors

IFAC Proceedings Volumes 2008年第2期41卷 12923-12928页

作者： Filip Logist Peter M. Van Erdeghem Ilse Y. Smets Jan F. Van Impe BioTeC Department of Chemical Engineering Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven Belgium. (Tel: +32-16-32.26.75

This paper deals with the optimal and safe operation of jacketed tubular reactors. Despite the existence of advanced distributed controllers, optimal steady-state reference profiles to be tracked are often unknown. In Logist et al. [2008], a procedure which combines analytical and numerical optimal control techniques, has been proposed for deriving optimal analytical (and thus generic) references, and it has been illustrated for plug flow reactors. The aim of this paper is to illustrate the general applicability of this procedure by allowing dispersion. As dispersion significantly complicates a possible solution process (due to second-order derivatives and split boundary conditions), hardly any generic results are known. Nevertheless, the dispersive plug flow reactor model is important for practice, since varying the dispersion level allows to mimic an entire reactor range, i.e., from plug flow to perfectly mixed reactors. As an example a jacketed tubular reactor in which an exothermic irreversible first-order reaction takes place is adopted. It is shown that the procedure yields generic reference solutions for ( i ) three different cost criteria, and ( ii ) different dispersion levels.

关键词： chemical industry distributed-parameter systems model-based control optimal control reactor control second-order systems

来源：评论

学校读者我要写书评

暂无评论

Optimal control of distributed-parameter systems based on differentiable orthogonal functions

Optimal control of distributed-parameter systems based on di...

引用

6th IASTED International Conference on Intelligent systems and Control

作者： Wang, QY Zhu, Y Nanjing Univ Sci & Technol Dept Automat Nanjing 210094 Peoples R China

ISBN: (纸本)0889864365

Taking the advantages of the properties of the differentiability of differentiable orthogonal functions, such as the Chebyshev function sequences, we can apply differential operation matrices, instead of the corresponding integral operation matrices, to the solution of the optimal control of distributed-parameter systems. The advantage of this method is that we can solve the optical control problems through differential operations and obtain an analytical linear presentation of the optimal solutions. As we know, the operation process based on the method of integral operations for solving such problems is quite sophisticated and tedious. The method based on differentiable orthogonal functions presented in this paper can greatly simplify the solution process and avoid such complex work and the solution results are quite satisfactory. The proposed method of the differentiable function sequences approach for the solution in this paper avoids tedious integral operations and is characterized by directness and feasibility.

关键词： Chebyshev sequences distributed-parameter systems optimal control differentiable operation matrices

来源：评论

学校读者我要写书评

暂无评论

Virtual Decomposition Control of a Planar Flexible-Link Robot

引用

IFAC Proceedings Volumes 2008年第2期41卷 1697-1702页

作者： Wen-Hong Zhu Christian Lange Mathilde Callot Spacecraft Engineering Space Technologies Canadian Space Agency 6767 route de l'Aeroport Saint-Hubert QC Canada J3Y 8Y9 (Tel: 450-926-5177

Use of flexible link robots is motivated by applications featuring lightweight or long arms. However, the control problem faces strong technical challenges resulting from the complex dynamics. In this paper, the virtual decomposition control (VDC) approach is applied for the first time to address the technical challenges of this thorny problem mainly resulting from the dynamic coupling effects among flexible links. In view of the VDC approach, the control problem of a multiple-flexible-link robot is no more complex than the control problem of individual flexible links subject to kinematics constraints. A planar beam governed by Euler-Bernoulli equation is studied as an example for simplicity. A possible extension to robots with multiple flexible links is theoretically possible by creating appropriate virtual power flows at the two ends of each beam. The validity of the theoretical results is verified by simulations with respect to two typical space systems in planar motion.

关键词： Virtual decomposition control Flexible arms Robot control End point control Model-based control distributed-parameter systems Partial differential equations

来源：评论

学校读者我要写书评

暂无评论

Optimal activation policies for continuous scanning observations in parameter estimation of distributed systems

引用

INTERNATIONAL JOURNAL OF systems SCIENCE 2006年第11期37卷 763-775页

作者： Patan, Maciej Univ Zielona Gora Inst Control & Computat Engn Zielona Gora Poland

The problem of determining an optimal measurement scheduling for identification of unknown parameters in distributed systems described by partial differential equations is discussed. The discrete- scanning observations are performed by an optimal selection of measurement data from spatially fixed sensors. In the adopted approach, the sensor scheduling problem is converted to a constrained optimal control problem. In this framework, the control value represents the selected sensor configuration. Thus the control variable is constrained to take values in a discrete set and switchings between sensors may occur in continuous time. By applying the control parameterization enhancing transform technique, a computational procedure for solving the optimal scanning measurement problem is obtained. The numerical scheme is then tested on a computer example regarding an advection- diffusion problem.

关键词： distributed-parameter systems sensor scheduling parameter estimation

来源：评论

学校读者我要写书评

暂无评论

IDENTIFICATION MODELS OF A ONE-DIMENSIONAL SPACE- TIME PROCESS

引用

CYBERNETICS AND systems ANALYSIS 2007年第5期43卷 704-718页

作者： Skopetskii, V. V. Stoyan, V. A. Natl Acad Sci Ukraine VM Glushkov Inst Cybernet Kiev Ukraine Taras Shevehenko Natl Univ Kiev Ukraine

Problems of constructing linear and polynomially nonlinear mathematical models are solved for distributed space-time processes with discretely-continuously observable states under distributed space-time perturbations that create such states. The cases of exact and optimal (with respect to the mean-square criterion) identification of kernels of such models are considered. The identifiability conditions are specified for the process and accuracy conditions are established for its mathematical models.

关键词： distributed-parameter systems dynamics simulation identification the Green function

来源：评论

学校读者我要写书评

暂无评论

Constraints driven optimal actuation policies for diffusion processes with collocated actuators and sensors

Constraints driven optimal actuation policies for diffusion ...

引用

26th American Control Conference

作者： Dubljevic, Stevan Univ Calif Los Angeles David Geffen Sch Med Los Angeles CA 90095 USA

ISBN: (纸本)9781424409884

This work introduces modal model predictive control (MMPC) design methodology in the framework of optimal actuation policies which arise due to the presence of input and state constraints for a class of distributed parameter systems modeled by parabolic PDEs. The predictive control law accounts for input and state constraints and with respect to actuator/sensor position placement it generates an optimal actuation policy that switches applied control action among available pre-specified actuator locations. The proposed constrained predictive control law utilizes a low order modal representation in the optimization functional while higher modes are included only in the PDE state constraints. Accordingly, the proposed control law is formulated by the minimization algorithm whereby optimization is performed over all available preset collocated actuator/sensor positions. In this sense, the minimizing algorithm provides a control law that chooses among best collocated actuator/sensor positions available with respect to the lowest optimal cost among these positions. An example of a diffusion-reaction process, with spatially-uniform unstable steady state, subject to flux boundary conditions is considered.

关键词： distributed-parameter systems model predictive control input/state constraints optimal actuator switching

来源：评论

学校读者我要写书评

暂无评论

AN ALGEBRAIC APPROACH TO THE CONTROL OF SPATIALLY distributed systems — THE 2-D systems CASE WITH A PHYSICAL APPLICATION

引用

IFAC Proceedings Volumes 2007年第20期40卷 196-201页

作者： P. Augusta Z. Hurák E. Rogers Institute of Information Theory and Automation Academy of Sciences Prague Czech Republic School of Electronics and Computer Science University of Southampton Southampton UK

In this paper we develop new results on control systems design for spatially distributed linear systems using an n -D systems approach. The basic ideas are explained using as an example heat conduction in a rod where the measurements and control action applied are based on an array of sensors and heaters. The first part of the analysis given shows how the process dynamics for this case can be approximately described by a 2-D transfer function, i.e. a fraction of two bivariate polynomials. This is followed by stability analysis and tests. Finally, a Youla-Kucera parametrization of all stabilizing controllers is used to develop a simple design procedure for H 2 -optimal control laws.

关键词： distributed-parameter systems spatially distributed systems multidimensional systems multivariate polynomials

来源：评论

学校读者我要写书评

暂无评论

INTEGRODIFFERENTIAL APPROACH TO OPTIMAL CONTROL PROBLEMS OF ELASTIC BEAM MOTIONS

引用

IFAC Proceedings Volumes 2007年第14期40卷 153-156页

作者： G.V. Kostin V.V. Saurin Institute for Problems in Mechanics of the Russian Academy of Sciences

An approach to modeling and optimization of controlled dynamical systems with distributed elastic and inertial parameters is considered. The general method of integrodifferential relations (IDR) for solving a wide class of boundary value problems is developed and criteria of solution quality are proposed. A numerical algorithm for discrete approximation of controlled motions has been worked out and applied to design the optimal control law moving an elastic system to the terminal position and minimizing the given objective function. The polynomial control for plane motions of a homogeneous cantilever beam is investigated. The optimal control problem of beam transportation from the initial rest position to given terminal states, in which the total mechanical energy of the system reaches its minimal value, is considered. Copyright © 2002 IFAC

关键词： Approximate analysis distributed-parameter systems Optimal control

来源：评论

学校读者我要写书评

暂无评论

OPTIMAL JACKETED TUBULAR REACTOR OPERATION: CLASSIC VS. FLOW REVERSAL

引用

IFAC Proceedings Volumes 2007年第5期40卷 355-360页

作者： F. Logist A. Vande Wouwer I.Y. Smets J.F. Van Impe BioTeC Dept of Chemical Engineering K.U.Leuven W. de Croylaan 46 B-3001 Leuven Belgium Service d'Automatique Faculté Polytechnique de Mons Boulevard Dolez 31 B-7000 Mons Belgium

Optimal steady-state temperature profiles for jacketed tubular reactors often exhibit a trapezoidal shape along the reactor, i.e., first an increase, then a constant part and finally a decrease (Smets et al. , 2002; Logist et al. , 2006&). The practical realisation of these reactor temperature profiles is complex given the (infinite dimensional) spatially varying jacket fluid temperature profile required for the constant reactor temperature part. Therefore, based on simulations this paper compares two practically feasible alternatives with a near-optimal performance. The first splits the jacket into a finite number of isothermal zones. The second considers a flow reversal strategy, which also induces trapezoidally shaped temperature profiles (Logist et al. , 2006a).

关键词： chemical reactors computer-aided design computer simulation distributed-parameter systems model-based control optimal control

来源：评论

学校读者我要写书评

暂无评论

Stability analysis of controlled, partially-connected, distributed-parameter systems through perturbation methods

引用

JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS 2003年第2期116卷 379-392页

作者： Robertson, LM Balas, MJ USAF Res Lab Space Vehicles Directorate Kirtland AFB NM 87117 USA Univ Colorado Dept Aerosp Engn Boulder CO 80309 USA

A stability result for locally-controlled, interconnected, distributed-parameter systems (DPS) is developed. Using a special perturbation operator, exponential stability is shown to be a function of both the value of the perturbation operator and the characteristics of the interconnected DPS. Proof of the bound is shown using the expansion of the matrix operator and the solution vector through a set of gauge functions. Each expansion term is power matched and individually bound using stationary phase methods. Special consideration is given to interconnected systems of a structural dynamic nature.

关键词： distributed-parameter systems perturbation theory induction methods control

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：