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1.
Multimedia Tools and Applications - The designing of 2-D digital differentiator is multimodal and high dimensional problem which requires large number of differentiator coefficients to be...  相似文献   

2.
This paper presents sliding mode tracking control for a class of uncertain nonlinear systems with unknown parameters and system states. The sliding mode tracking controller with the differential evolution (DE) algorithm using integral-chain differentiator (ICD) is designed for the trajectory tracking in uncertain nonlinear systems. The ICD added into the sliding mode tracking systems provides the estimation of unknown states. The DE optimisation algorithm on the basis of ICD realises the unknown parametric identification in the limitation of unknown system states. The simulation is implemented to illustrate that the combined control scheme achieves high precision tracking performances.  相似文献   

3.
针对目前差分进化算法收敛速度慢,易出现早熟的问题,提出一种新的带惯性变异与正交设计的差分进化改进算法。在经典差分进化算法的基础上,对每一代群体中优于前一代的个体执行惯性变异,寻求发现更优个体,在每一代群体更新结束后,对群体中最优个体在其局部邻域内使用正交设计方法进行搜索,加快发现最优解的速度。通过对7个常用的基准测试函数进行测试,结果表明提出的算法在求解精度、收敛速度、稳定性和扩展性等方面均有很好的表现,明显优于经典差分进化算法和目前常见的差分进化改进算法。  相似文献   

4.
This paper is concerned with the cost minimization of prestressed concrete beams using a special differential evolution-based technique. The optimum design is posed as single-objective optimization problem in presence of constraints formulated in accordance with the current European building code. The design variables include geometrical dimensions that define the shape of the cross section and the amount of prestressing steel. A special (μ?+?λ)-constrained differential evolution method is performed in order to solve the optimization problem. Its search mechanism depends on several mutation strategies whereas an archiving-based adaptive tradeoff model is in charge of selecting a specific constraint-handling technique. Finally, numerical examples are included to illustrate the application of the presented approach.  相似文献   

5.
Signal filtering can be treated as one of the basic requisite of communication networks. Design of an appropriate digital filter demands such filter coefficients that will create the desired frequency response with tolerable amount of ripples in the stop band(s) and pass band(s) along with high attenuation in the stop band(s). Now-a-days, artificial evolutionary methods are employed in the modern digital filter design due to lots of advantages over typical methods. In this paper, multipurpose digital linear phase double band filter (LPDBF) is designed proposing a hybrid meta-heuristic technique called hybrid firefly differential evolution (HFDE) algorithm. Generally these filters are required in different specific modern digital system networks for the simultaneous processing of signals present in two or three different channels. The proposed HFDE is an efficient evolutionary hybrid technique and is modelled considering both the optimization advantages of improved differential evolution (IDE) and firefly techniques. The global searching capability of IDE technique is strengthened by improved firefly movement. The performance of the proposed HFDE method of LPDBF design is contrasted with few popular optimal methods of design.  相似文献   

6.
A cellular neural network (CNN) based edge detector optimized by differential evolution (DE) algorithm is presented. Cloning template of the proposed CNN is adaptively tuned by using simple training images. The performance of the proposed edge detector is evaluated on different test images and compared with popular edge detectors from the literature. Simulation results indicate that the proposed CNN operator outperforms competing edge detectors and offers superior performance in edge detection in digital images.  相似文献   

7.
正交差分演化算法在工程优化设计中的应用   总被引:1,自引:1,他引:0  
提出一种基于正交设计的快速差分演化算法,并把它应用于工程优化设计中。新算法在保留传统差分演化算法简单、有效等特性的同时,还具有以下一些特点:(1)引入一种基于正交设计的杂交算子,并结合约束统计优生法来产生最好子个体;(2)提出一种简单的多样性规则,以处理约束条件;(3)简化基本差分演化算法的缩放因子,尽量减少算法的控制参数,方便工程人员的使用。通过对2个工程优化实例进行实验,并与其他算法的结果作比较,其结果表明,新算法在解的精度、稳定性、收敛性和收敛速度上表现出很好的性能,并且对所优化的问题没有特殊的要求,具有很好的普适性。  相似文献   

8.
为了解决基本差分进化算法易出现早熟收敛的问题, 提出了一种融合人工免疫系统和差分进化的混合算法。该算法在差分进化过程中引入了克隆选择操作和受体编辑机制, 以增强算法的局部搜索能力和种群多样性。通过对五个标准函数的仿真实验表明, 该算法不仅可有效避免早熟收敛, 而且全局优化能力和收敛速度有显著提高。  相似文献   

9.
Many engineering problems can be categorized into constrained optimization problems (COPs). The engineering design optimization problem is very important in engineering industries. Because of the complexities of mathematical models, it is difficult to find a perfect method to solve all the COPs very well. \(\varepsilon \) constrained differential evolution (\(\varepsilon \)DE) algorithm is an effective method in dealing with the COPs. However, \(\varepsilon \)DE still cannot obtain more precise solutions. The interaction between feasible and infeasible individuals can be enhanced, and the feasible individuals can lead the population finding optimum around it. Hence, in this paper we propose a new algorithm based on \(\varepsilon \) feasible individuals driven local search called as \(\varepsilon \) constrained differential evolution algorithm with a novel local search operator (\(\varepsilon \)DE-LS). The effectiveness of the proposed \(\varepsilon \)DE-LS algorithm is tested. Furthermore, four real-world engineering design problems and a case study have been studied. Experimental results show that the proposed algorithm is a very effective method for the presented engineering design optimization problems.  相似文献   

10.
李康顺  左磊  李伟 《计算机应用》2016,36(1):143-149
为了克服传统差分演化(DE)算法在求解约束优化问题时出现的收敛性慢和容易陷入早熟等缺陷,提出一种新的基于单形正交实验设计的差分演化(SO-DE)算法。该算法设计了一种结合单形交叉和正交实验设计的混合交叉算子来提高差分演化算法的搜索能力;同时采用了一种改进的个体优劣比较准则对种群个体进行比较和选择。这种新的混合交叉算子利用多个父代个体进行单形交叉产生多个子代个体,从两者中选择优秀个体进行正交实验设计得到下一代种群个体。改进的个体优劣比较准则对不同状态下的种群采用不同的处理方案,其目的在于能够有效地权衡目标函数值和约束违反量之间的关系,从而选择优秀个体进入下一代种群。通过对13个标准测试函数和2个工程设计问题进行仿真实验,实验结果表明SO-DE算法求解的精度和标准方差都要优于HEAA算法和COEA/OED算法。SO-DE算法具有更高的精度以及更好的稳定性。  相似文献   

11.
Solving engineering design and resources optimization via multiobjective evolutionary algorithms (MOEAs) has attracted much attention in the last few years. In this paper, an efficient multiobjective differential evolution algorithm is presented for engineering design. Our proposed approach adopts the orthogonal design method with quantization technique to generate the initial archive and evolutionary population. An archive (or secondary population) is employed to keep the nondominated solutions found and it is updated by a new relaxed form of Pareto dominance, called Pareto-adaptive ϵ-dominance (paϵ-dominance), at each generation. In addition, in order to guarantee to be the best performance produced, we propose a new hybrid selection mechanism to allow the archive solutions to take part in the generating process. To handle the constraints, a new constraint-handling method is employed, which does not need any parameters to be tuned for constraint handling. The proposed approach is tested on seven benchmark constrained problems to illustrate the capabilities of the algorithm in handling mathematically complex problems. Furthermore, four well-studied engineering design optimization problems are solved to illustrate the efficiency and applicability of the algorithm for multiobjective design optimization. Compared with Nondominated Sorting Genetic Algorithm II, one of the best MOEAs available at present, the results demonstrate that our approach is found to be statistically competitive. Moreover, the proposed approach is very efficient and is capable of yielding a wide spread of solutions with good coverage and convergence to true Pareto-optimal fronts.  相似文献   

12.
A new method based on the differential evolution (DE) algorithm is proposed for antenna-array pattern synthesis with prescribed nulls. The array excitation amplitudes are the only controlling parameters, and the objectives are to synthesize array patterns with nulls imposed on directions of interferences while keeping the sidelobe levels (SLLs) below prescribed levels. Many factors such as the excitation dynamic range ratio, null depth level, null width, and SLLs are taken into account in the synthesis. Simulation results of several typical problems are compared with published results to illustrate the effectiveness of the proposed method. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14: 57–63, 2004.  相似文献   

13.
为了克服差分进化算法容易出现早熟和收敛速度慢的问题,提出了一种混合差分进化算法.该算法在趋药性差分进化算法(CDE)的基础上,通过对较优个体进行变异操作,维护了种群多样性、避免早熟;通过将较差的个体与较优个体进行杂交,提高了开采能力、加快了收敛速度.基于这两种策略,算法的开采能力与探索能力达到了平衡.用该算法解决标准函数优化问题,并将仿真结果与其他算法进行比较,数值结果表明该文算法具有较快的收敛速度和很强的跳出局部最优的能力.  相似文献   

14.
一种新的差分进化算法   总被引:2,自引:0,他引:2       下载免费PDF全文
针对高维复杂函数的优化问题,提出了一种新的差分进化算法(NDE)。该算法在运行中根据迭代次数自动地调整交叉概率因子,从而在搜索的初始阶段提高种群多样性,而在搜索后期加强局部搜索能力。对几种经典函数的测试表明,新算法不仅具有很强的全局搜索能力,而且能有效避免早熟收敛问题。  相似文献   

15.
针对变异算子学习方式的单一性,提出一种朴素变异算子,其基本思想是向优秀的个体靠近,同时远离较差个体,其实现方式是设计一种缩放因子调整策略,如果三个随机个体在某维上比较接近,则缩放因子变小,反之变大.在实验过程中通过平均适应度评价次数、成功运行次数和加速比等指标表明,基于朴素变异算子的差分进化算法能有效提高算法的收敛速度和健壮性.  相似文献   

16.
This paper presents a fast terminal sliding‐mode tracking control for a class of uncertain nonlinear systems with unknown parameters and system states combined with time‐varying disturbances. Fast terminal sliding‐mode finite‐time tracking systems based on differential evolution algorithms incorporate an integral chain differentiator (ICD) to feedback systems for the estimation of the unknown system states. The differential evolution optimization algorithm using ICD is also applied to a tracking controller, which provides unknown parametric estimation in the limitation of unknown system states for trajectory tracking. The ICD in the tracking systems strengthens the tracking controller robustness for the disturbances by filtering noises. As a powerful finite‐time control effort, the fast terminal sliding‐mode tracking control guarantees that all tracking errors rapidly converge to the origin. The effectiveness of the proposed approach is verified via simulations, and the results exhibit high‐precision output tracking performance in uncertain nonlinear systems.  相似文献   

17.
如何有效地确定模糊Petri网(FPN)的各项参数、摆脱自学习能力差的缺点,一直是悬而未决的问题。针对此问题,将差分进化算法首次引入到FPN参数优化中,根据FPN的实际特征,提出了一种改进的差分进化算法。算法采用混沌策略产生初始种群,融合自适应变异因子及早熟惩罚策略提高种群多样性,同时保证很强的收敛性与全局性。仿真实验表明,将改进的差分进化算法与传统算法相比较,收敛到理想参数值的速度提高了5倍。  相似文献   

18.
Profit-based unit-commitment problem (PBUCP) is a notable combinatorial optimizing problem faced in the deregulated power industry. The PBUCP finds the best profitable solution by committing and scheduling the thermal generating units efficiently. To solve the PBUCP, a new memetic binary differential evolution algorithm is proposed which considers binary differential evolution (BDE) algorithm as global search operator to improve the exploration aspect and binary hill-climbing (BHC) algorithm as local search operator to improve the exploitation aspect. A binary differential evolution algorithm is introduced whereby a new mutation strategy is implemented. A novel BHC algorithm makes priority-based perturbations on unit’s status to improve the global best solution searched by the BDE algorithm alone. A new excessive unit de-commitment strategy based on priority and total profit is also proposed. The power to committed units is allocated based on priority of units. The efficacy of algorithms has been researched on the PBUCP test systems comprising of 10-, 40- and 100-units over a time horizon. The outcomes of the proposed algorithms are compared with previously known best solutions. Simulated outcomes achieved by the proposed algorithms compete with the already reported algorithms to solve the PBUCP. Wilcoxon signed-rank test proves the predominance of the proposed algorithms statistically.  相似文献   

19.
Differential evolution (DE) is a powerful yet simple evolutionary algorithm for optimization of real-valued, multimodal functions. DE is generally considered as a reliable, accurate and robust optimization technique. However, the algorithm suffers from premature convergence and/or slow convergence rate resulting in poor solution quality and/or larger number of function evaluation resulting in large CPU time for optimizing the computationally expensive objective functions. Therefore, an attempt to speed up DE is considered necessary. This research introduces a modified differential evolution (MDE) that enhances the convergence rate without compromising with the solution quality. The proposed MDE algorithm maintains a failure_counter (FC) to keep a tab on the performance of the algorithm by scanning or monitoring the individuals. Finally, the individuals that fail to show any improvement in the function value for a successive number of generations are subject to Cauchy mutation with the hope of pulling them out of a local attractor which may be the cause of their deteriorating performance. The performance of proposed MDE is investigated on a comprehensive set of 15 standard benchmark problems with varying degrees of complexities and 7 nontraditional problems suggested in the special session of CEC2008. Numerical results and statistical analysis show that the proposed modifications help in locating the global optimal solution in lesser numbers of function evaluation in comparison with basic DE and several other contemporary optimization algorithms.  相似文献   

20.
针对网络防火墙、路由器等设备中包匹配的速度问题,提出运用差分演化算法实现包匹配多层核心基的提取。该算法运用多层基础基描述包的多层特征,在每层中分别运用差分演化算法进行比特基和实体基的提取,运用平均自信息和平均互信息量衡量基础基选择的优劣。这种方法可以根据规则库实际规模选择提取比特实体基的层数,非常适应规则库的增长。实验结果表明,所提算法在时间效率、空间效率方面相对于已有的递归数据流匹配算法和基于实数编码的差分演化的包匹配算法,综合性能最优。  相似文献   

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