One of the basic requirements in grasping and manipulation of objects is the determination of a suitable set of grasping forces such that the external forces and torques applied on the object are balanced and the obje...
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An algorithm for computing the minimum distance between two convex polyhedra is presented. The algorithm is applied to polyhedral objects which can be represented as convex hulls of its value of vertices in three-dime...
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An algorithm for computing the minimum distance between two convex polyhedra is presented. The algorithm is applied to polyhedral objects which can be represented as convex hulls of its value of vertices in three-dimensional space. nonlinear programming techniques are then employed to computer the minimum distance between two convex polyhedra, and according to the minimum distance, it can be concluded whether or not the objects will collide. The algorithm of collision detecting presented in this paper improves the efficiency of collision detecting by simulation experiences.
In this paper, a general multiperiod nonlinear optimization model is presented, which incorporates synthesis, design, and operation, and takes into account the corresponding benefits and costs in each time period. The...
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In this paper, a general multiperiod nonlinear optimization model is presented, which incorporates synthesis, design, and operation, and takes into account the corresponding benefits and costs in each time period. The model is formulated as a non linear programming (NLP) model in which plant structure decisions are modeled in terms of a superstructure embedded in the overall model. This approach is novel since it involves new decision variables, integrates algebraic and differential equations, and solves a NLP problem even when discrete decisions are involved. The proposed model is applied to a Brandy production plant with high detail level in the operations description. The optimal solution is found and different tradeoffs between process and design variables are assessed.
A study of grade transitions as encountered in polymerization reactors is presented. The results underscore the need for global optimization algorithms to fully realize the benefits of grade transition that are necess...
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A study of grade transitions as encountered in polymerization reactors is presented. The results underscore the need for global optimization algorithms to fully realize the benefits of grade transition that are necessarily non-convex. For comparison purposes we use a non-gradient, parallel search, stochastic method, namely differential evolution (DE). Our simulations indicate that while the DE solution is highly dependent on the algorithm parameters and mutation strategy, the SQP solution depends on the initial guess value and consistently provides faster convergence. Finally, we also explore the issue of evaluating the optimal grade changeover time. All of the above issues have been demonstrated for the grade transition of polymethyl methacrylate (PMMA) in a non-isothermal CSTR.
Both real-time and off-line optimizations are commonly performed in order to enhance productivity. The optimization problem is often posed as a nonlinear programming (NLP) problem solved by a SQP algorithm. When proce...
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Both real-time and off-line optimizations are commonly performed in order to enhance productivity. The optimization problem is often posed as a nonlinear programming (NLP) problem solved by a SQP algorithm. When processes need to be described by differential equations, difficulties will arise in using SQP algorithms, since Jacobians of constraints described by differential equations will have to be evaluated. In this paper, we show how to derive analytical expressions for both Jacobian and Hessian matrices for the constraints described by ordinary differential equations, without increasing the dimension of the resultant NLP problem to be solved.
The present paper presents an approach of identifying the structure of a dynamic system using Mixed Integer nonlinear programming (MINLP) techniques. It is shown that the problem can be tackled by minimizing, for exam...
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The present paper presents an approach of identifying the structure of a dynamic system using Mixed Integer nonlinear programming (MINLP) techniques. It is shown that the problem can be tackled by minimizing, for example, Akaike's Information Criterion (AIC). The presented techni ques are applied in determining the structure and the parameters of some illustrative Auto-Regressive Moving Average (ARMA) time series. The example problems are solved using the Extended Cutting Plane (ECP) method.
Generally, researchers are faced to identify the true statistical distributions for the analysis of a various hydrologic data sets. Using traditional statistical analysis methods one choose a hypothesized distribution...
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OPTRAGEN is a MATLAB toolbox for numerically solving optimal control problems. OPTRAGEN translates optimal control problems of the form min_(x(t),u(t)) J velence (PHI)_(i)(x(t_(0)), u(t_(0)), t_(0)) min_(x(t),u(t)) J ...
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ISBN:
(纸本)1424401704;9781424401703
OPTRAGEN is a MATLAB toolbox for numerically solving optimal control problems. OPTRAGEN translates optimal control problems of the form min_(x(t),u(t)) J velence (PHI)_(i)(x(t_(0)), u(t_(0)), t_(0)) min_(x(t),u(t)) J velence + integral from x=t_(0) to x=t_(f) of (PHI)_(t)(x(t), u(t), t)d(tau) min_(x(t),u(t)) J velence +(PHI)_(f)(x(t_(f)), u(t_(f)), t_(f)) subject to dynamics x velence f(x, u, t) and constraints l_(i) <= (PSI)_(i)(x(t_(0)), u(t_(0)), t_(0)) <= u_(i) (Init. Constr.) l_(t) <= (PSI)_(t)(x(t), u(t),t) <= u_(t) (Traj. Const.) l_(f) <= (PSI)_(f)(x(t_(f)), u(t_(f)), t_(f)) <= u_(f) (Final Constr.), to nonlinear programming problems of the form min from rho of F(rho) subject to L <= {rho} <= U. L <= {A(rho)} <= U. L <= {G(rho)} <= U. The transcription of optimal control problem (OCP) to nonlinear programming (NLP) problem is done by parameterizing trajectories as Splines. The output of the transcription is a cost function and a constraint function that can be interfaced with any commercially available nonlinear programming solver. OPTRAGEN can be considered to be a parser that translates optimal control problems to nonlinear programming problems, and is not dependent on any nonlinear programming solver.
In this paper, a new kind of optimal design model and methodology for large flexible antenna in space with deployed and retracted states are investigated. The purpose is to search for a minimum weight design by means ...
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ISBN:
(纸本)0780393953
In this paper, a new kind of optimal design model and methodology for large flexible antenna in space with deployed and retracted states are investigated. The purpose is to search for a minimum weight design by means of selecting the cables' tension and cross-sectional areas of the surround truss whilst satisfying the constraints such as, for deployed state, the precision of reflector surface, material strength, eigenfrequency and variables sides, and, for retracted state, the stowage volume, eigenfrequency, material strength and variables sides. To solve the problem, an improved genetic algorithm (GAs) is proposed and applied to a 17-m-diameter antenna with reasonable result, which is currently under design and manufacturing in China.
Considering the characteristics of mesh reflector antenna, two adjusting methodologies are proposed in this paper. One is to search for highest reflector precision whilst satisfying nonlinear constrains, such as eigen...
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ISBN:
(纸本)0780393953
Considering the characteristics of mesh reflector antenna, two adjusting methodologies are proposed in this paper. One is to search for highest reflector precision whilst satisfying nonlinear constrains, such as eigen frequency, material strength and sides by finding the optimum adjusting cables' increment. The other is to search for the highest reflector precision and the minimum adjusting cable numbers whilst satisfying the same constraints as the above by finding out two kinds of variables, i.e., number of adjusting cables and increment of adjusting cables' length. Obviously the latter is a nonlinear programming problem with two objectives and both continuous and discrete design variables. The numerical simulation of a 17 m cable mesh antenna is carried out to demonstrate the methodology given in this paper.
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