共查询到20条相似文献，搜索用时 21 毫秒
1.
2.
萤火虫算法是一种新的智能算法,被广泛的使用在优化问题的解决方面,针对算法存在收敛速度慢,求解精度低的缺点,提出了引入人工鱼群算法中的聚群行为和追尾行为改进算法,仿真实验采用3个经典测试函数来测试本文算法和萤火虫算法,实验结果说明了本文算法能够有效的提高性能。 相似文献
3.
4.
针对当前可用输电能力计算存在着易早熟、收敛速度慢等问题,提出了一种改进的人工鱼群算法进行求解,提高了计算结果的准确性、收敛性能以及计算速度。人工鱼群算法是群智能随机全局优化技术,该算法引入了禁忌搜索算法中的记忆功能,可以有效避免迂回搜索并提高计算的效率。在对人工鱼搜索的机制进行研究的基础上,对寻优行为进行改进,采用最好解优先选择前进的路径并以排序选择的方式接受劣解,从而进一步提高算法的效率。修改过的IEEE 30节点系统的计算结果表明,改进人工鱼群算法用于可用输电能力计算是有效的,具有良好的全局收敛性能和较高的计算效率。 相似文献
5.
6.
粒子群优化(PSO)粒子滤波算法比较而言,容易陷入局部最优,因此算法的准确度就会降低。本文在解决该问题时引入了一种基于鱼群的PSO粒子滤波算法。此算法是通过鱼群优化在采样过程中找到全局最优的相对位置,使其能够向全局最优的位置逐渐接近,同时提高估计有效的粒子数目,从而能够更有效的减少粒子退化与枯竭问题。实验表明,此算法与PSO粒子滤波算法相比,在估计准确度方面有了较大的提升。 相似文献
7.
研究人工鱼群算法优化问题,为了改进AFSA在非全局极值点出现较严重聚集情况时,收敛速度降低,甚至陷入局部极值,搜索性能劣化的问题,采用细胞膜优化算法物质的转运方式,对人工鱼群算法的寻优行为进行改进,从而一定程度上避免算法陷入局部最优,提出了一种基于细胞膜优化的人工鱼群算法.通过4个典型函数仿真和应用实例仿真结果表明,该算法是可行有效的,求解精度更高,算法更稳定. 相似文献
8.
9.
10.
《科技通报》2017,(2)
Adhoc的组播路由问题需要考虑延迟、带宽、费用和丢包率等服务质量约束的问题,其本质是一个NP问题。本文将人工蜂群算法和粒子群算法进行混合,在蜂群算法的蜜源更新的公式中引入柯西分布,能够帮助探路蜂跳出局部最优,提高产生全局最优解的速度,使用列维飞行可以减少寻找优化解的时间,在粒子群算法中采用自适应参数变换的思想,加速了产生种群的最优解。本文算法应用在Ad Hoc网络的组播路由算法中,在满足Qo S约束函数的前提下,降低了产生路由最优解的费用,缩短了时间。仿真实验说明本文的算法与基本的人工蜂群算法和粒子群算法相比在网络时延,网络消耗费用,网络成本和丢包率方面具有很好的效果。 相似文献
11.
12.
We consider the problem of placing copies of objects in a distributed web server system to minimize the cost of serving read and write requests when the web servers have limited storage capacities. We formulate the problem as a 0–1 optimization problem and present a hybrid particle swarm optimization algorithm to solve it. The proposed hybrid algorithm makes use of the strong global search ability of particle swarm optimization (PSO) and the strong local search ability of tabu search to obtain high quality solutions. The effectiveness of the proposed algorithm is demonstrated by comparing it with the genetic algorithm (GA), simple PSO, tabu search, and random placement algorithm on a variety of test cases. The simulation results indicate that the proposed hybrid approach outperforms the GA, simple PSO, and tabu search. 相似文献
13.
针对现有水资源配置模型存在的不精确问题,在现有水资源模型基础上增加了决策偏好系数和排放污染物种类以提高模型精确性,以吉林市水资源基础数据初始化水资源优化配置模型,针对目前对模型进行优化的粒子群算法易出现局部最优等情况,引入萤火虫算法对其进行改进,通过萤火虫趋向最优解的原理改善粒子群算法出现局部最优的情况,并加速其收敛速度。应用改进粒子群算法对模型进行优化求解,得出水资源优化配置方案,以满足经济效益、社会效益、生态环境效益的全面要求。 相似文献
14.
阐述了运用粒子群优化人工神经网络建立煤层顶板导水裂隙带高度预测模型的思路与方法。利用粒子群优化神经网络模型的权值和阈值,克服了神经网络容易收敛到局部最小值,以及收敛速度慢的缺点。煤层导水裂隙带高度预测实例表明,该方法不仅能更快地收敛于最优解,且预测精度有明显的提高。 相似文献
15.
《Information processing & management》2022,59(5):103005
In real-life applications, resources in construction projects are always limited. It is of great practical importance to shorten the project duration by using intelligent models (i.e., evolutionary computations such as genetic algorithm (GA) and particle swarm optimization (PSO) to make the construction process reasonable considering the limited resources. However, in the general EC-based model, for example, PSO easily falls into a local optimum when solving the problem of limited resources and the shortest period in scheduling a large network. This paper proposes two PSO-based models, which are resource-constrained adaptive particle swarm optimization (RC-APSO) and an input-adaptive particle swarm optimization (iRC-APSO) to respectively solve the static and dynamic situations of resource-constraint problems. The RC-APSO uses adaptive heuristic particle swarm optimization (AHPSO) to solve the limited resource and shortest duration problem based on the analysis of the constraints of process resources, time limits, and logic. The iRC-APSO method is a combination of AHPSO and network scheduling and is used to solve the proposed dynamic resource minimum duration problem model. From the experimental results, the probability of obtaining the shortest duration of the RC-APSO is higher than that of the genetic PSO and GA models, and the accuracy and stability of the algorithm are significantly improved compared with the other two algorithms, providing a new method for solving the resource-constrained shortest duration problem. In addition, the computational results show that iRC-APSO can obtain the shortest time constraint and the design scheme after each delay, which is more valuable than the static problem for practical project planning. 相似文献
16.
分布式水循环模型的参数优化算法比较及应用 总被引：1，自引：0，他引：1
分布式水文模型的优势在于还原水文过程的时空变异性,可以很好地模拟和反映各种水文要素和下垫面因素的时空分布不均匀性。由此也导致模型参数过多,在子流域过多的情况下,人工调节参数繁琐复杂,应用优化算法实现参数自动调节成为首选。本文选取石羊河流域九条岭站1988-2005年实测径流资料,分别应用SCE-UA算法、遗传算法(GA)和粒子群算法(PSO)对分布式水循环模型(时变增益模型)进行参数率定,对比3种算法的收敛速度、所需迭代次数和算法稳定性。结果表明:通过SCE-UA、GA和PSO的优化,模型水平衡系数都控制在0.0左右,而相关系数和效率系数分别能达到0.90和0.84以上,模拟精度较好。但粒子群算法的全局搜索能力和收敛速度优于SCE-UA和遗传算法,所需迭代次数最少,初值敏感性小,更适合时变增益模型的参数寻优,有很高的扩展性和改进潜力。 相似文献
17.
Yogendra Arya 《Journal of The Franklin Institute》2018,355(5):2662-2688
The interconnected large-scale power systems are liable to performance degradation under the presence of sudden small load demands, parameter ambiguity and structural changes. Due to this, to supply reliable electric power with good quality, robust and intelligent control strategies are extremely requisite in automatic generation control (AGC) of power systems. Hence, this paper presents an output scaling factor (SF) based fuzzy classical controller to enrich AGC conduct of two-area electrical power systems. An implementation of imperialist competitive algorithm (ICA) is made to optimize the output SF of fuzzy proportional integral (FPI) controller employing integral of squared error criterion. Initially the study is conducted on a well accepted two-area non-reheat thermal system with and without considering the appropriate generation rate constraint (GRC). The advantage of the proposed controller is illustrated by comparing the results with fuzzy controller and bacterial foraging optimization algorithm (BFOA)/genetic algorithm (GA)/particle swarm optimization (PSO)/hybrid BFOA-PSO algorithm/firefly algorithm (FA)/hybrid FA-pattern search (hFA-PS) optimized PI/PID controller prevalent in the literature. The proposed approach is further extended to a newly emerged two-area reheat thermal-PV system. The superiority of the method is depicted by contrasting the results of GA/FA tuned PI controller. The proposed control approach is also implemented on a multi-unit multi-source hydrothermal power system and its advantage is established by Correlating its results with GA/hFA-PS tuned PI, hFA-PS/grey wolf optimization (GWO) tuned PID and BFOA tuned FPI controllers. Finally, a sensitivity analysis is performed to demonstrate the robustness of the proposed method to broad changes in the system parameters and size and/or location of step load perturbation. 相似文献
18.
粒子群优化（PSO）算法是一种模拟自然生物群体（swarm）行为的优化技术。PSO算法源于对鸟群觅食行为的研究,该算法简单易实现,可调参数少,已得到广泛研究和应用。PSO算法不仅仅是种算法,更是一种学习和思维的创新,体现出学科之间交互所发生的一些突破。它不但是计算机理论上极大的理论创新,而且在哲学上也具有丰富的内涵。对此进行了论述。 相似文献
19.
The optimal location of a static synchronous compensator (STATCOM) and its coordinated design with power system stabilizers (PSSs) for power system stability improvement are presented in this paper. First, the location of STATCOM to improve transient stability is formulated as an optimization problem and particle swarm optimization (PSO) is employed to search for its optimal location. Then, coordinated design problem of STATCOM-based controller with multiple PSS is formulated as an optimization problem and optimal controller parameters are obtained using PSO. A two-area test system is used to show the effectiveness of the proposed approach for determining the optimal location and controller parameters for power system stability improvement. The nonlinear simulation results show that optimally located STATCOM improves the transient stability and coordinated design of STATCOM-based controller and PSSs improve greatly the system damping. Finally, the coordinated design problem is extended to a four-machine two-area system and the results show that the inter-area and local modes of oscillations are well damped with the proposed PSO-optimized controllers. 相似文献
20.
《Information processing & management》2020,57(5):102255
Collaborative frequent itemset mining involves analyzing the data shared from multiple business entities to find interesting patterns from it. However, this comes at the cost of high privacy risk. Because some of these patterns may contain business-sensitive information and hence are denoted as sensitive patterns. The revelation of such patterns can disclose confidential information. Privacy-preserving data mining (PPDM) includes various sensitive pattern hiding (SPH) techniques, which ensures that sensitive patterns do not get revealed when data mining models are applied on shared datasets. In the process of hiding sensitive patterns, some of the non-sensitive patterns also become infrequent. SPH techniques thus affect the results of data mining models. Maintaining a balance between data privacy and data utility is an NP-hard problem because it requires the selection of sensitive items for deletion and also the selection of transactions containing these items such that side effects of deletion are minimal. There are various algorithms proposed by researchers that use evolutionary approaches such as genetic algorithm(GA), particle swarm optimization (PSO) and ant colony optimization (ACO). These evolutionary SPH algorithms mask sensitive patterns through the deletion of sensitive transactions. Failure in the sensitive patterns masking and loss of data have been the biggest challenges for such algorithms. The performance of evolutionary algorithms further gets degraded when applied on dense datasets. In this research paper, victim item deletion based PSO inspired evolutionary algorithm named VIDPSO is proposed to sanitize the dense datasets. In the proposed algorithm, each particle of the population consists of n number of sub-particles derived from pre-calculated victim items. The proposed algorithm has a high exploration capability to search the solution space for selecting optimal transactions. Experiments conducted on real and synthetic dense datasets depict that VIDPSO algorithm performs better vis-a-vis GA, PSO and ACO based SPH algorithms in terms of hiding failure with minimal loss of data. 相似文献