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人体系统非优性的进化论诠释 被引量:3
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作者 吴廷瑞 《医学与哲学》 1999年第1期20-23,共4页
从进化论的角度论述了人体系统非优性的成因,说明了生物进化在人体系统中保留下大量的时空沉迹。其形式与特征表现为层次套叠,多元集合,转化退化。从而成为新与旧、高级与低级、复杂与简单,一句话就是优与非优相互缠绕、相互作用、... 从进化论的角度论述了人体系统非优性的成因,说明了生物进化在人体系统中保留下大量的时空沉迹。其形式与特征表现为层次套叠,多元集合,转化退化。从而成为新与旧、高级与低级、复杂与简单,一句话就是优与非优相互缠绕、相互作用、互补关联的协同统一体。而疾病的发生则是这种辩证统一的失调或破坏。 展开更多
关键词 人体系统 非优性 进化论 医学哲学
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人体系统的非优性与疾病的时空特征 被引量:5
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作者 吴廷瑞 《医学与哲学》 1995年第6期292-294,共3页
人体系统并非完美,生命抛物线是由生理年龄、社会年龄、人体熵三大要素在非线性作用下相干的结果,从而呈现现一种复杂的网状“大X构架”。每一个交叉点都具有阶段性态变的意义和对生命质量的表征。疾病是人体系统非优的必然。熵压决... 人体系统并非完美,生命抛物线是由生理年龄、社会年龄、人体熵三大要素在非线性作用下相干的结果,从而呈现现一种复杂的网状“大X构架”。每一个交叉点都具有阶段性态变的意义和对生命质量的表征。疾病是人体系统非优的必然。熵压决定了熵的退行性运动,从而也决定了生命时间的有限性。疾病是熵增过程造成机体不同程度封闭的结果。每次疾病都是对熵的增压,造成机体的物质丢失、时间丢失与跳跃,出现熵运动方向的引力偏折,从而在局部时空上出现结构异位、功能失常、信息失真,进而影响整个机体对物能的吞吐能力及对熵的交换质量。疾病在时空上的分布又是决定性与随机性的统一。 展开更多
关键词 人体系统 非优性 疾病 时空特征 医学哲学
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对免疫系统非优性的探讨
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作者 李华 朱锡华 吴廷瑞 《医学与哲学》 2000年第2期19-21,共3页
免疫系统是维持机体自身稳定的一个重要系统。从系统的功能、环境和信息方面阐述免疫系统优与非优的表现和关系;并提出由于免疫系统存在非优信息的特点,科研人员在对免疫系统认识过程中应客观、全面,在认识事物优的同时也应看到事物... 免疫系统是维持机体自身稳定的一个重要系统。从系统的功能、环境和信息方面阐述免疫系统优与非优的表现和关系;并提出由于免疫系统存在非优信息的特点,科研人员在对免疫系统认识过程中应客观、全面,在认识事物优的同时也应看到事物非优的一面。 展开更多
关键词 免疫系统 非优性
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X-刀的两面观 被引量:1
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作者 吴胜青 张可成 吴廷瑞 《医学与哲学》 1998年第2期89-90,共2页
X-刀的两面观第三军医大学第二附属医院神经外科(重庆400037)吴胜青张可成吴廷瑞科学进入20世纪后,特别是二战后的和平时期,高新科学在很短时间内酝酿发育,立即获得了迅猛发展的态势。在这个形势下,科学创造了以往任何... X-刀的两面观第三军医大学第二附属医院神经外科(重庆400037)吴胜青张可成吴廷瑞科学进入20世纪后,特别是二战后的和平时期,高新科学在很短时间内酝酿发育,立即获得了迅猛发展的态势。在这个形势下,科学创造了以往任何时代都不可想象的技术奇迹,X-刀就... 展开更多
关键词 X刀 手术适应症 辨证分析 非优性
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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怎样认识自由基
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作者 周仲玲 许霖水 《医学与哲学》 1996年第10期533-533,共1页
怎样认识自由基第三军医大学基础生化教研室研究生(重庆630038)周仲玲导师许霖水一、自由基的非优性1.环境污染与自由基:在地球外层空间的臭氧层,对保护地球上的生物有机体免受过量紫外线和宇宙线的攻击很重要。但在地球下... 怎样认识自由基第三军医大学基础生化教研室研究生(重庆630038)周仲玲导师许霖水一、自由基的非优性1.环境污染与自由基:在地球外层空间的臭氧层,对保护地球上的生物有机体免受过量紫外线和宇宙线的攻击很重要。但在地球下层大气中,天空闪电、植物呼吸、汽车... 展开更多
关键词 自由基 非优性 优异 医学哲学
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Analysis of Mine Ventilation Network Using Genetic Algorithm
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作者 谢贤平 冯长根 王海亮 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期33-38,共6页
Aim To determine the global optimal solution for a mine ventilation network under given network topology and airway characteristics. Methods\ The genetic algorithm was used to find the global optimal solution of the ... Aim To determine the global optimal solution for a mine ventilation network under given network topology and airway characteristics. Methods\ The genetic algorithm was used to find the global optimal solution of the network. Results\ A modified genetic algorithm is presented with its characteristics and principle. Instead of working on the conventional bit by bit operation, both the crossover and mutation operators are handled in real values by the proposed algorithms. To prevent the system from turning into a premature problem, the elitists from two groups of possible solutions are selected to reproduce the new populations. Conclusion\ The simulation results show that the method outperforms the conventional nonlinear programming approach whether from the viewpoint of the number of iterations required to find the optimum solutions or from the final solutions obtained. 展开更多
关键词 mine ventilation network nonlinear programming OPTIMIZATION genetic algorithms
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New Math Model for Designing Engine Radiator
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作者 黄虹宾 刘淑艳 +1 位作者 郑世琴 阎为革 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期141-146,共6页
Aim To raise the H-NE math model for designing engine radiators.Methods Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original data.Through the sens... Aim To raise the H-NE math model for designing engine radiators.Methods Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original data.Through the sensitivity analysis about radiatoroptimization designing,some major restraints were obtained.Results Type 1301C radiator wasoptimizingly renwed by use o this model,and the new radiator is more excellent than theold one in respect of the heat transfer factor and the manufacturing cost.Conclusion Theradiation performance can be improved,the area can be reduced,and the fitting scope can bewidened if this model is used in designing radiators. 展开更多
关键词 radiator performance multi-nonlinear regression analysis optimizing design
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DISCRETE BIDIRECTIONAL ASSOCIATIVE MEMORY WITH LEARNING FUNCTION
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作者 王正欧 魏清刚 王红晔 《Transactions of Tianjin University》 EI CAS 1999年第1期25-30,共6页
In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the opti... In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the optimal associative mapping proposed by Kohonen. Like LBAM and NBAM proposed by one of the present authors,the present BAM ensures the guaranteed recall of all stored patterns,and possesses far higher capacity compared with other existing BAMs,and like NBAM, has the strong ability to suppress the noise occurring in the output patterns and therefore reduce largely the spurious patterns. The derivation of DBAM is given and the stability of DBAM is proved. We also derive a learning algorithm for DBAM,which has iterative form and make the network learn new patterns easily. Compared with NBAM the present BAM can be easily implemented by software. 展开更多
关键词 bidirectional associative memory cross inhibitory connections optimal associative mapping nonlinear function stability of network memory capacity noise suppression
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Swarm intelligence for mixed-variable design optimization 被引量:7
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作者 郭创新 胡家声 +1 位作者 叶彬 曹一家 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期851-860,共10页
Many engineering optimization problems frequently encounter continuous variables and discrete variables which adds considerably to the solution complexity. Very few of the existing methods can yield a globally optimal... Many engineering optimization problems frequently encounter continuous variables and discrete variables which adds considerably to the solution complexity. Very few of the existing methods can yield a globally optimal solution when the objective functions are non-convex and non-differentiable. This paper presents a hybrid swarm intelligence ap-proach (HSIA) for solving these nonlinear optimization problems which contain integer, discrete, zero-one and continuous variables. HSIA provides an improvement in global search reliability in a mixed-variable space and converges steadily to a good solution. An approach to handle various kinds of variables and constraints is discussed. Comparison testing of several examples of mixed-variable optimization problems in the literature showed that the proposed approach is superior to current methods for finding the best solution, in terms of both solution quality and algorithm robustness. 展开更多
关键词 Swarm intelligence Mixed variables Global optimization Engineering design optimization
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Swarm intelligence optimization and its application in geophysical data inversion 被引量:30
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作者 Yuan Sanyi Wang Shangxu Tian Nan 《Applied Geophysics》 SCIE CSCD 2009年第2期166-174,共9页
The inversions of complex geophysical data always solve multi-parameter, nonlinear, and multimodal optimization problems. Searching for the optimal inversion solutions is similar to the social behavior observed in swa... The inversions of complex geophysical data always solve multi-parameter, nonlinear, and multimodal optimization problems. Searching for the optimal inversion solutions is similar to the social behavior observed in swarms such as birds and ants when searching for food. In this article, first the particle swarm optimization algorithm was described in detail, and ant colony algorithm improved. Then the methods were applied to three different kinds of geophysical inversion problems: (1) a linear problem which is sensitive to noise, (2) a synchronous inversion of linear and nonlinear problems, and (3) a nonlinear problem. The results validate their feasibility and efficiency. Compared with the conventional genetic algorithm and simulated annealing, they have the advantages of higher convergence speed and accuracy. Compared with the quasi-Newton method and Levenberg-Marquardt method, they work better with the ability to overcome the locally optimal solutions. 展开更多
关键词 Swarm intelligence optimization geophysical inversion MULTIMODAL particle swarm optimization algorithm
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Neural Network Nonlinear Predictive Control Based on Tent-map Chaos Optimization 被引量:5
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作者 宋莹 陈增强 袁著祉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期539-544,共6页
With the unique erggdicity, i rregularity, and.special ability to avoid being trapped in local optima, chaos optimization has been a novel global optimization technique and has attracted considerable attention for a... With the unique erggdicity, i rregularity, and.special ability to avoid being trapped in local optima, chaos optimization has been a novel global optimization technique and has attracted considerable attention for application in various fields, such as nonlinear programming problems. In this article, a novel neural network nonlinear predic-tive control (NNPC) strategy baseed on the new Tent-map chaos optimization algorithm (TCOA) is presented. Thefeedforward neural network'is used as the multi-step predictive model. In addition, the TCOA is applied to perform the nonlinear rolling optimization to enhance the convergence and accuracy in the NNPC. Simulation on a labora-tory-scale liquid-level system is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 model-based predictive control neural network Tent-map chaos optimization nonlinear system
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A novel stabilization approach for small signal disturbance of power system with time-varying delay 被引量:4
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作者 杨波 孙元章 《Journal of Central South University》 SCIE EI CAS 2013年第12期3522-3527,共6页
Small signal instability may cause severe accidents for power system if it can not be dear correctly and timely. How to maintain power system stable under small signal disturbance is a big challenge for power system o... Small signal instability may cause severe accidents for power system if it can not be dear correctly and timely. How to maintain power system stable under small signal disturbance is a big challenge for power system operators and dispatchers. Time delay existing in signal transmission process makes the problem more complex. Conventional eigenvalue analysis method neglects time delay influence and can not precisely describe power system dynamic behaviors. In this work, a modified small signal stability model considering time varying delay influence was constructed and a new time delay controller was proposed to stabilize power system under disturbance. By Lyapunov-Krasovskii function, the control law in the form of nonlinear matrix inequality (NLMI) was derived. Considering synthesis method limitation for time delay controller at present, both parameter adjustment method by using linear matrix inequality (LMI) solver and iteration searching method by solving nonlinear minimization problem were suggested to design the controller. Simulation tests were carried out on synchronous-machine infinite-bus power system. Satisfactory test results verify the correctness of the proposed model and the feasibility of the stabilization approach. 展开更多
关键词 power system stability small signal disturbance time-varying delay power system stabilizer
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Collective Directional Transport in Symmetric Periodic Potentials by Breaking the Coupling Symmetry 被引量:1
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作者 LIXiao-Wen ZHENGZHi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期549-554,共6页
Collective unidirectional motion of an asymmetrically coupled array of oscillators in symmetric periodic potentials is studied. A directed current is observed when the drift coupling is presented, while no external bi... Collective unidirectional motion of an asymmetrically coupled array of oscillators in symmetric periodic potentials is studied. A directed current is observed when the drift coupling is presented, while no external biased force is applied. Negative directed current is found when varying system parameters. An addition of a periodic rocking force may enhance the efficiency of directed transport. Resonant steps of the current are found and interpreted as the mode locking between the array and the ac force. Noise-assisted transport is observed, and an optimal noise intensity can give rise to a most efficient transport. The directed transport thus can be optimized and furthermore controlled by suitably adjusting the parameters of the system. 展开更多
关键词 directional transport mode locking stochastic resonance
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PIECEWISE LINEAR NCP FUNCTION FOR QP FREE FEASIBLE METHOD 被引量:6
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作者 Pu Dingguo Zhou Yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期289-301,共13页
In this paper, a QP-free feasible method with piecewise NCP functions is proposed for nonlinear inequality constrained optimization problems. The new NCP functions are piecewise linear-rational, regular pseudo-smooth... In this paper, a QP-free feasible method with piecewise NCP functions is proposed for nonlinear inequality constrained optimization problems. The new NCP functions are piecewise linear-rational, regular pseudo-smooth and have nice properties. This method is based on the solutions of linear systems of equation reformulation of KKT optimality conditions, by using the piecewise NCP functions. This method is implementable and globally convergent without assuming the strict complementarity condition, the isolatedness of accumulation points. Purr thermore, the gradients of active constraints are not requested to be linearly independent. The submatrix which may be obtained by quasi-Newton methods, is not requested to be uniformly positive definite. Preliminary numerical results indicate that this new QP-free method is quite promising. 展开更多
关键词 constrained optimization SEMISMOOTH nonlinear complementarity convergence.
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Particle swarm optimization based RVM classifier for non-linear circuit fault diagnosis 被引量:5
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作者 高成 黄姣英 +1 位作者 孙悦 刁胜龙 《Journal of Central South University》 SCIE EI CAS 2012年第2期459-464,共6页
A relevance vector machine (RVM) based fault diagnosis method was presented for non-linear circuits. In order to simplify RVM classifier, parameters selection based on particle swarm optimization (PSO) and preprocessi... A relevance vector machine (RVM) based fault diagnosis method was presented for non-linear circuits. In order to simplify RVM classifier, parameters selection based on particle swarm optimization (PSO) and preprocessing technique based on the kurtosis and entropy of signals were used. Firstly, sinusoidal inputs with different frequencies were applied to the circuit under test (CUT). Then, the resulting frequency responses were sampled to generate features. The frequency response was sampled to compute its kurtosis and entropy, which can show the information capacity of signal. By analyzing the output signals, the proposed method can detect and identify faulty components in circuits. The results indicate that the fault classes can be classified correctly for at least 99% of the test data in example circuit. And the proposed method can diagnose hard and soft faults. 展开更多
关键词 non-linear circuits fault diagnosis relevance vector machine particle swarm optimization KURTOSIS ENTROPY
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Application of a Derivative-Free Method with Projection Skill to Solve an Optimization Problem 被引量:1
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作者 PENG Fei SUN Guo-Dong 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第6期499-504,共6页
Improving numerical forecasting skill in the atmospheric and oceanic sciences by solving optimization problems is an important issue. One such method is to compute the conditional nonlinear optimal perturbation(CNOP),... Improving numerical forecasting skill in the atmospheric and oceanic sciences by solving optimization problems is an important issue. One such method is to compute the conditional nonlinear optimal perturbation(CNOP), which has been applied widely in predictability studies. In this study, the Differential Evolution(DE) algorithm, which is a derivative-free algorithm and has been applied to obtain CNOPs for exploring the uncertainty of terrestrial ecosystem processes, was employed to obtain the CNOPs for finite-dimensional optimization problems with ball constraint conditions using Burgers' equation. The aim was first to test if the CNOP calculated by the DE algorithm is similar to that computed by traditional optimization algorithms, such as the Spectral Projected Gradient(SPG2) algorithm. The second motive was to supply a possible route through which the CNOP approach can be applied in predictability studies in the atmospheric and oceanic sciences without obtaining a model adjoint system, or for optimization problems with non-differentiable cost functions. A projection skill was first explanted to the DE algorithm to calculate the CNOPs. To validate the algorithm, the SPG2 algorithm was also applied to obtain the CNOPs for the same optimization problems. The results showed that the CNOPs obtained by the DE algorithm were nearly the same as those obtained by the SPG2 algorithm in terms of their spatial distributions and nonlinear evolutions. The implication is that the DE algorithm could be employed to calculate the optimal values of optimization problems, especially for non-differentiable and nonlinear optimization problems associated with the atmospheric and oceanic sciences. 展开更多
关键词 differential evolution algorithm spectral projected gradient algorithm CNOP Burgers' equation optimization problem
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Modified Self-adaptive Immune Genetic Algorithm for Optimization of Combustion Side Reaction of p-Xylene Oxidation 被引量:1
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作者 陶莉莉 孔祥东 +1 位作者 钟伟民 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1047-1052,共6页
In recent years, immune genetic algorithm (IGA) is gaining popularity for finding the optimal solution for non-linear optimization problems in many engineering applications. However, IGA with deterministic mutation fa... In recent years, immune genetic algorithm (IGA) is gaining popularity for finding the optimal solution for non-linear optimization problems in many engineering applications. However, IGA with deterministic mutation factor suffers from the problem of premature convergence. In this study, a modified self-adaptive immune genetic algorithm (MSIGA) with two memory bases, in which immune concepts are applied to determine the mutation parameters, is proposed to improve the searching ability of the algorithm and maintain population diversity. Performance comparisons with other well-known population-based iterative algorithms show that the proposed method converges quickly to the global optimum and overcomes premature problem. This algorithm is applied to optimize a feed forward neural network to measure the content of products in the combustion side reaction of p-xylene oxidation, and satisfactory results are obtained. 展开更多
关键词 self-adaptive immune genetic algorithm artificial neural network measurement p-xylene oxidation process
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Optimal Seat Suspension Design Using Genetic Algorithms 被引量:3
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作者 Wael Abbas Ossama B. Abouelatta +2 位作者 Magdy El-Azab Mamdouh El-Saidy Adel A. Megahed 《Journal of Mechanics Engineering and Automation》 2011年第1期44-52,共9页
The linear seat suspension is considered due to the low cost consideration therefore, the optimal linear seat suspension design method can be used for this purpose. In this paper, the design of a passive vehicle seat ... The linear seat suspension is considered due to the low cost consideration therefore, the optimal linear seat suspension design method can be used for this purpose. In this paper, the design of a passive vehicle seat suspension system was handled in the framework of linear optimization. The variance of the dynamic load resulting from the vibrating vehicle operating at a constant speed was used as the performance measure of a suspension system. Using 4-DOF human body model developed by Abbas et al., with linear seat suspension and coupled with half car model. A genetic algorithm is applied to solve the linear optimization problem. The optimal design parameters of the seat suspension systems obtained are kse = 3 012.5 N/m and cse = 1 210.4 N.s/m, respectively. 展开更多
关键词 Biodynamic response seated human models SIMULATION genetic algorithms.
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Nonlinear optimization of load allocation in a manufacturing system
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作者 郭彩芬 王宁生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第3期343-346,共4页
Based on the queuing theory, a nonlinear optimization model is proposed in this paper. A novel transformation of optimization variables is devised and the constraints are properly combined so as to make this model int... Based on the queuing theory, a nonlinear optimization model is proposed in this paper. A novel transformation of optimization variables is devised and the constraints are properly combined so as to make this model into a convex one, from which the Lagrangian function and the KKT conditions are derived. The interiorpoint method for convex optimization is presented here as a computationally efficient tool. Finally, this model is evaluated on a real example, from which such conclusions are drawn that the optimum result can ensure the full utilization of machines and the least amount of WIP in manufacturing systems; the interior-point method for convex optimization needs fewer iterations with significant computational savings. It appears that many non-linear ootimization oroblems in the industrial engineering field would be amenable to this method of solution. 展开更多
关键词 load allocation queuing theory convex optimization
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