共查询到20条相似文献，搜索用时 15 毫秒
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Bilender P. Allahverdiev Hüseyin Tuna Yüksel Yalinkaya 《Mathematical Methods in the Applied Sciences》2019,42(10):3508-3526
In this article, we discuss a conformable fractional Sturm‐Liouville boundary‐value problem. We prove an existence and uniqueness theorem for this equation and formulate a self‐adjoint boundary value problem. We also construct the associated Green function of this problem, and we give the eigenfunction expansions. Finally, we will give some examples. 相似文献
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由于粒子群算法在处理高维复杂函数时存在容易陷入局部最优的问题,提出了多种群子空间学习粒子群算法(SLPSO),采用多种群进化模式,在粒子更新公式中加入了全局最优粒子,加快了粒子收敛速度,同时在种群之间采用了交叉学习的方法,大大提高了算法的全局搜索能力.另外,还增加了一种子空间学习方法,充分地利用粒子的历史经验,有效地避免了陷入局部最优的问题.通过在高维基准测试函数的仿真实验表明,SLPSO算法的测试结果都明显优于其他两种算法,随着函数维数增加,SLPSO算法测试结果的下降幅度明显低于其他两种算法.在6个极其复杂的复合函数的测试中,SLPSO算法有2个测试函数结果非常接近理论值,其他4个也明显优于其他三种算法. 相似文献
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Raweerote Suparatulatorn Phakdi Charoensawan Kanyuta Poochinapan 《Mathematical Methods in the Applied Sciences》2019,42(18):7268-7284
We introduce a new self‐adaptive algorithm for applications to image restoration problems. In order to study an image restoration, we consider the algorithm that contains inertial effects and step sizes, which is independent from the norm of the bounded linear operator. With some control conditions, the strong convergence to the minimum norm solution of the algorithm is obtained. Convergence analysis of the proposed algorithm is also discussed. Moreover, numerical results of image restoration problems illustrate that the proposed algorithm is efficient and outperforms other ones. 相似文献
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The paper introduces an intelligent decision-making model which is based on the application of artificial neural networks (ANN) and swarm intelligence technologies. The proposed model is used to generate one-step forward investment decisions for stock markets. The ANN are used to make the analysis of daily stock returns and to calculate one day forward decision for purchase of the stocks. Subsequently the Particle Swarm Optimization (PSO) algorithm is applied in order to select the “the best” ANN for the future investment decisions and to adapt the weights of other networks towards the weights of the best network. The experimental investigations were made considering different forms of decision-making model: different number of ANN, ANN inputs, sliding windows, and commission fees. The paper introduces the decision-making model, its evaluation results and discusses its application possibilities. 相似文献
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本文依照更具有现实意义的“加工厂—配送中心—用户”的模式建立物流配送中心连续型选址模型,并针对较大规模的选址问题提出求解算法。该算法是将具有较强鲁棒性的自适应粒子算法和改进的ALA(Alert Location-Allocation)方法结合而得,该算法中种群规模自适应变化,对经典粒子移动方程进行改进,消除了学习因子,惯性因子随粒子适应值自适应变化,改进的ALA方法提高了算法计算效率。数值试验表明,本文所建模型具有一定的实践优越性,所提出的算法能有效避免陷入局部最优,寻优能力和鲁棒性均较强。 相似文献
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基于GA-SVM的太原市空气质量指数预测 总被引：1，自引：0，他引：1
针对大气环境的复杂多变性和不确定性,采用太原市2014年至2016年的空气污染物监测数据,分别将改进的粒子群算法(IPSO)和遗传算法(GA)与支持向量机(SVM)相结合,通过参数寻优构建新模型完成对空气质量指数(AQI)的预测.实验结果表明,GA-SVM在预测精度、误差率和可靠性方面均优于IPSO-SVM与SVM.因此GA-SVM模型更适用于AQI的预测,为大气污染防治提供了科学合理的理论依据和新的预测方法. 相似文献
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Flying-V是一种典型的非传统布局方式,根据其布局方式的特性,针对仓储货位分配优化问题,以货物出入库效率最高和货物存放的重心最低为优化目标,建立了货位分配多目标优化模型,并采用自适应策略的遗传算法(GA),以及粒子群算法(PSO)进行求解。根据货位分配的优化特点,在GA算法的选择、交叉和变异环节均采用自适应策略, 同时采用惯性权重线性递减的方法设计了PSO算法,有效地解决了两种算法收敛速度慢和易“早熟”的问题,提高了算法的寻优性能。为了更好地表现两种优化求解算法的有效性和优越性,结合具体的货位分配实例利用MATLAB软件编程实现。通过对比分析优化结果表明,PSO算法在收敛速度和优化效果方面相比于自适应GA算法更具有优势,更加合适于解决Flying-V型仓储布局货位分配优化问题。 相似文献
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王丰效 《数学的实践与认识》2011,41(20)
GM(1,1)幂模型是灰色Verhulst模型的推广.由于初始条件选取影响GM(1,1)幂模型的精度,将平均相对误差函数分别看成是幂指数、发展系数、灰作用量的函数,利用蚁群算法进行参数辨识,从而建立多个单项GM(1,1)幂模型.利用这些单项模型建立了线性组合GM(1,1)幂模型,组合权系数利用最大相对误差最小化原则采用粒子群算法确定.实例表明,组合GM(1,1)幂模型的建模精度高于传统GM(1,1)幂模型,同时也说明方法是有效的和可行的,具有重要的理论意义. 相似文献
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研究无人机任务规划问题,从无人机侦查和轰炸两方面入手.首先,运用迭代算法求解出从基地到雷达区域边际上任一目标出入口的最短路径.在此基础上,以无人机在雷达范围内滞留时间最短,以及被探测次数最少为目标,建立多目标最优化模型.通过改进交叉算子的遗传算法找出最优侦查路径.对于轰炸任务,以无人机在雷达范围内滞留时间最短,以及轰炸总时间最短为目标,建立多目标最优化模型.采用改变惯性权重的自适应粒子群算法找出最佳轰炸路线.由于计算时间较长,本文对68个目标进行聚类分析,提出针对轰炸任务的快速算法,相较原轰炸方案,其计算效率提高80%以上. 相似文献
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等间距灰色GOM（1,1）模型是一种基于反向累加生成的灰色预测模型．为了拓广适用范围,提高GOM（1,1）模型的拟合和预测精度,给出了非等间距灰色GOM（1,1）模型的建模方法,并利用粒子群优化算法对非等间距灰色GOM（1,1）模型的参数进行优化．最后,利用一个仿真实例,表明基于粒子群优化算法的灰色GOM（1,1）模型... 相似文献
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Fabrizio Colombo Samuele Mongodi Marco Peloso Stefano Pinton 《Mathematical Methods in the Applied Sciences》2019,42(5):1662-1686
Let e?, for ? = 1,2,3, be orthogonal unit vectors in and let be a bounded open set with smooth boundary ?Ω. Denoting by a point in Ω, the heat equation, for nonhomogeneous materials, is obtained replacing the Fourier law, given by the following: into the conservation of energy law, here a, b, are given functions. With the S‐spectrum approach to fractional diffusion processes we determine, in a suitable way, the fractional powers of T. Then, roughly speaking, we replace the fractional powers of T into the conservation of energy law to obtain the fractional evolution equation. This method is important for nonhomogeneous materials where the Fourier law is not simply the negative gradient. In this paper, we determine under which conditions on the coefficients a, b, the fractional powers of T exist in the sense of the S‐spectrum approach. More in general, this theory allows to compute the fractional powers of vector operators that arise in different fields of science and technology. This paper is devoted to researchers working in fractional diffusion and fractional evolution problems, partial differential equations, and noncommutative operator theory. 相似文献
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Fabrizio Colombo Marco M. Peloso Stefano Pinton 《Mathematical Methods in the Applied Sciences》2019,42(18):6259-6276
In the recent years, there has been a lot of interest in fractional diffusion and fractional evolution problems. The spectral theory on the S‐spectrum turned out to be an important tool to define new fractional diffusion operators stating from the Fourier law for nonhomogeneous materials. Precisely, let e?, e?=1,2,3 be orthogonal unit vectors in and let be a bounded open set with smooth boundary ?Ω. Denoting by a point in Ω, the heat equation is obtained replacing the Fourier law given by into the conservation of energy law. In this paper, we investigate the structure of the fractional powers of the vector operator T, with homogeneous Dirichlet boundary conditions. Recently, we have found sufficient conditions on the coefficients a, b, such that the fractional powers of T exist in the sense of the S‐spectrum approach. In this paper, we show that under a different set of conditions on the coefficients a, b, c, the fractional powers of T have a different structure. 相似文献
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从资产组合管理角度出发,用信用风险修正的方法对企业信用等级阈值进行修正,同时考虑商业银行持续经营的特点,将修正后的信用风险引入到多阶段的模型当中去,建立一个基于信用风险修正的多阶段银行资产组合优化模型.针对该模型的特点,给出了把Monte Carlo模拟的动态算法和改进粒子群的多阶段算法相结合求解方法.数值试验表明所建... 相似文献
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Yasin Fadaei Ali Ahmadi Kiavash Fekri Rohollah Masoumi Ami Radunskaya 《Mathematical Methods in the Applied Sciences》2021,44(1):391-406
In this study, a mathematical, fractional‐order model was developed for B cell chronic lymphocytic leukemia, with immune system, and then analyzed. Interactions between B leukemia cells, natural killer cells, cytotoxic T cells, and T‐helper cells are considered to be incorporated into a system consisting of four fractional differential equations. For estimation of the parameters, clinical data of six patients were used. By numerical solution of the system, the interactions between the leukemia cell population and the immune system cell populations for values of α ∈ (0,1) at different times were explained. By determining points of equilibrium and stability of the system were met. Bifurcation analysis showed that use of the fractional‐order model, figure out unpredictable behaviors of the system such as saddle‐node, bistability and hysteresis phenomenon occurred in the system by changing the values of some of the parameters, it was predictable. 相似文献
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《Mathematical Methods in the Applied Sciences》2018,41(9):3430-3440
This paper deals with 2 core aspects of fractional calculus including existence of positive solution and Hyers‐Ulam stability for a class of singular fractional differential equations with nonlinear p‐Laplacian operator in Caputo sense. For these aims, the suggested problem is converted into an integral equation via Green function , for ε∈(n−1,n], where n≥4. Then, the Green function is examined whether it is increasing or decreasing and positive or negative function. After these properties, some classical fixed‐point theorems are used for the existence of positive solution. Hyers‐Ulam stability of the proposed problem is also considered. For the application of the results, an expressive example is included. 相似文献
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利用截断的Thiele连分式,本文给出了一个求解非线性单变量方程的单步迭代方法,并证明了所提出的迭代方法具有四阶收敛性.最后,本文通过一些数值例子说明了所提出的方法的有效性和表现. 相似文献
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In this paper, we study the original Meyer model of cartoon and texture decomposition in image processing. The model, which is a minimization problem, contains an l1‐based TV‐norm and an l∞‐based G‐norm. The main idea of this paper is to use the dual formulation to represent both TV‐norm and G‐norm. The resulting minimization problem of the Meyer model can be given as a minimax problem. A first‐order primal‐dual algorithm can be developed to compute the saddle point of the minimax problem. The convergence of the proposed algorithm is theoretically shown. Numerical results are presented to show that the original Meyer model can decompose better cartoon and texture components than the other testing methods. 相似文献