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1.
公交换乘算法的仿真研究   总被引:1,自引:0,他引:1  
研究建立城市公交换乘查询网络问题.传统的公交换乘算法忽略了公交乘客的出行寻求优化路径的心理,并且算法的时间效率较低.为了解决上述问题,提出乘坐公交车出行的最优方案为换乘次数最少并且距离最短的线路.首先建立了公交网络及最小换乘次数的数学模型,然后运用线性规划方法建立线性规划模型,重新构造公交站点的数据结构以改进原有的最小换乘算法,得到一个新的算法并用改进算法对线性规划模型进行求解.仿真结果表明:新算法为核心的公交网络查询仿真系统,在一定程度上可以提高城市公共交通系统的服务水平,为实际设计提供依据.  相似文献   

2.
Q学习算法中网格离散化方法的收敛性分析   总被引:6,自引:1,他引:5  
Q学习算法是Watkins提出的求解信息不完全马尔可夫决策问题的一种强化学习方法,要用Q学习算法来求解有连续状态和决策空间的随机最优控制问题,则需要先离散化问题的状态和决策空间,在本文中,我们证明了在满足一定的Lipschitz连续性和有关集合为紧集的条件下,随着网格密度的增加,空间离散化后Q学习算法求得的最优解依概率1收敛于原连续问题的最优解。  相似文献   

3.
针对目前大多数的低秩张量填充模型存在稀疏过约束而导致恢复数据的细微特征被忽略的现象,本文借助低秩矩阵分解和框架变换,引入软阈值算子的■范数正则项,提出一个基于近似稀疏正则化的低秩张量填充模型.为有效地求解该模型,我们将■范数改写为具有非线性不连续权函数的加权■范数,并用连续权函数逼近不连续权函数,在此基础上设计块逐次上界极小化的求解算法.在一定条件下,证明该算法的收敛性.大量实验表明,本文所提出的算法比现有一些经典算法能更好地重建得到图像的局部细节特征.  相似文献   

4.
一个基于约束图的参数化设计模型   总被引:1,自引:0,他引:1  
基于图论的约束求解方法是目前参数化设计的主要方法,此方法已经应用于许多商品化软件中。该文提出了一个基于几何约束图的参数化设计模型,并给出了参数化模型的数据结构和约束求解算法。此算法可以有效地检查系统的过约束和欠约束情况。  相似文献   

5.
针对一类带节点处理速率限制的连续时间容量网络,提出了该网络中的最短动态时间流问题,并给出其线性规划形式;通过分析该网络与经典网络之间的内在联系,利用最大接收流和退流的思想分别设计出准确求解两种网络最短动态时间流的高效算法;证明了算法的正确性并分析出算法有较小的复杂度;最后,通过一个算例演示了算法的执行。  相似文献   

6.
弹载SAR平台轨迹的设计是研究弹载SAR成像算法的前提。为了在满足SAR成像条件的同时降低导弹打击时间,需要对SAR成像导引头的弹道进行优化。该问题属于非线性最优控制问题,本文采用序列二次规划(SQP)优化算法进行求解。首先以波束驻留时间最小为指标函数,导弹俯仰、偏航加速度为优化变量,建立了SAR成像导引头三维弹道优化模型,模型的约束包括SAR成像约束、过载约束和导弹飞行高度约束。然后,将原最优控制问题进行参数化,转换成非线性规划问题,利用SQP算法进行求解。参数化时,离散节点越多,得到的非线性规划问题规模越大,求解速度就越慢。仿真结果表明,SQP算法能够有效解决SAR成像导引头三维弹道优化问题,得到的解满足模型约束。  相似文献   

7.
在基于目标函数线性化的序列线性规划矩阵方法(SLPMM)的框架下,研究了线性时不变系统静态 输出反馈(SOF)H¥ 控制问题的数值解法,提出了一种改进的SLPMM 算法:通过求解一个LMI 特征值问题得到 SLPMM 算法的初始解,减少了运算的迭代次数,并同时给出了对H¥ 范数的一个初始估计.文中给出了基于该算法 的静态输出反馈H¥ 控制问题的详细求解步骤,最后用一个飞机纵向控制器的设计实例说明算法的有效性.  相似文献   

8.
针对求解全局优化问题,有很多种求解方法.文中提出了一种快速求解一般无约束最优化问题的辅助函数方法,即 F-C 函数方法.该方法与填充函数法和跨越函数法相比较,既有相同点又有不同点. F-C 函数法最大的优点就是在极小化 F-C 函数阶段中只需要进行一次局部极小化算法就能得到比当前极小值更低的目标函数局部极小点.文中在无Lipschitz 连续的条件下,给出了一类新的求解全局优化问题的 F-C 函数.文中讨论了该 F-C 函数的优良性质并对该函数设计了相应的算法.最后,通过数值试验表明该 F-C 函数方法具有有效性和可行性  相似文献   

9.
基于异步时间段的原油混输调度连续时间建模研究   总被引:1,自引:0,他引:1  
采用严格的数学规划方法对沿海炼厂的原油混输调度问题进行了建模和求解,提出了一个基于异步时间段的连续时间混合整数非线性规划(MINLP)数学模型。该模型具有整型变量少,求解快的优点。采用求解一系列MILP来近似求解非凸的MINLP,避免了原油混输MILP模型产生的浓度不一致问题。文中采用提出的新模型和算法对文献中的9个实例进行了计算,相同计算条件的4个实例比离散时间模型效率提高86%-1011%。  相似文献   

10.
提出通过分片线性逼近和分片线性规划,将非线性优化问题转化为一系列的线性规划进行求解的方法。讨论了分片线性规划的性质,证明了分片线性规划问题可以通过有限次线性规划得到求解,同时,给出了分片线性规划问题局部最优解的充要条件,并基于此构造了求解分片线性规划问题的下降算法。该算法与自适应链接超平面模型相结合,成功地对离心式冷水机组的工作点进行了优化。通过优化,机组的能耗比之当前工作点有了明显的下降,表明通过分片线性规划求解非线性优化问题的有效性。  相似文献   

11.
Algorithms developed to solve linear programming (LP) problems and advances in computer speed have made large-scale LP problems solvable in time for implementation. Solving an LP is relatively easier than solving an MIP for modern production planning problems. In this study, we propose a heuristic iterative algorithm between LP solution phases and setup decision computations for solving these difficult MIP production planning problems. By utilizing the shadow price information provided by the LP solution of the previous iteration, the setup decision computation converts an MIP problem into an LP problem, which can be efficiently solved in the current iteration. Extensive experiments show that the proposed heuristic algorithm performs well.  相似文献   

12.
This work presents a hybrid algorithm of Nested Partition (NP), Binary Ant System (BAS), and Linear Programming (LP) to solve the multidimensional knapsack problem (MKP). The hybrid NP+BAS+LP algorithm takes advantage of the global search strategies of the NP algorithm; the ability of BAS to quickly generate good solutions and incorporates information obtained from solving a LP relaxation of the MKP to help guide the search. It thus incorporates both the lower bounds (LB), found by the BAS, and the upper bounds (UB), found by solving the relaxed LP, into the search by embedding both in the NP framework. An adjustable computation budget is implemented where the number of samples increases if the LB and the UB point to different promising subregions. The proposed hybrid is compared to state-of-the-art solution techniques and is found to be one of the best algorithms in terms of the quality of solutions obtained and CPU time requirements.  相似文献   

13.
Linear programming(LP) is one of the most widely used Operations Research/Management Science/Industrial Engineering techniques. Recently, multiple criteria decision making or multiple objective linear programming has been well established as a practical approach to seeking satisfactory solutions to real-world decision problems.

In this paper we develop software tools for solving various linear programming problems such as a traditional LP problem, bicriteria LP problem, and multi-criteria LP problem on UNIX system. In a phase for reading data of various LP problems, we define a BNF(Backus-Nauel form) of various LP problems and implement BNF rules by using the C programming language.

In a phase for computing various LP problems, we use efficient methods for solving LP problems, develop various software tools on UNIX system, and combine each LP tool corresponding to an user request in which the Shell programming is used.

We also demonstrate some real-world LP problems by using LP software tools developed here on an UNIX System. Sanyo MPS 020.  相似文献   


14.
We compare the computational performance of linear programming (LP) and the policy iteration algorithm (PIA) for solving discrete-time infinite-horizon Markov decision process (MDP) models with total expected discounted reward. We use randomly generated test problems as well as a real-life health-care problem to empirically show that, unlike previously reported, barrier methods for LP provide a viable tool for optimally solving such MDPs. The dimensions of comparison include transition probability matrix structure, state and action size, and the LP solution method.  相似文献   

15.
Recently, a multiple criteria decision making (MCDM) has been well established as a practical approach to seek a satisfactory solution to a decision making problem. Linear programming (LP) is one of the most widely used OR/MS/IE techniques for solving MCDM problems. In the realistic decision making problems, many LP problems are involved a large number of 0–1 decision variables and a special type of system structures. So much kind of the large-scale 0–1 LP problems are simply too large fit into a microcomputer/workstation.

In this paper, we develop a software package micro 0–1LP(GUB) for solving LP problems with a generalized upper bounding (GUB) structure as large-scale 0–1LP problems on UNIX systems. From the views of the computational experience and storage requirement, micro 0–1LP(GUB) using the C programming language is implemented an efficient method in which the GUB structure would be effectively handled.

As a real-world large-scale 0–1LP problem with the GUB structures by the micro 0–1LP (GUB) software package developed here, we demonstrate an optimization problem of system reliability for selecting the allocating the components on an UNIX system, Sanyo/Icon MPS 020.  相似文献   


16.
This paper provides a unifying algorithm for computing any analytic interpolant of bounded complexity. Such computation can be performed by solving an optimization problem, due to a theorem by Georgiou and Lindquist. This optimization problem is numerically solvable by a continuation method. The proposed numerical algorithm is useful, among other cases, for designing a low-degree controller for a benchmark problem in robust control. The algorithm unifies previously developed algorithms for the Carathéodory extension and the Nevanlinna–Pick interpolation to one for more general interpolation problems.  相似文献   

17.
由于线性规划在理论和实践中的重要性,对求解大规模规划问题并行算法的研究已引起许多学者的兴趣.本文根据Galperin提出的线性规划的一种线性时间的立方算法特别适合并行的特点,提出了一种基于SPMD模型和主从式MPI的线性规划并行算法,并对算法性能进行了深入分析,理论分析和在曙光3000上的实验结果表明:该算法具有粗粒度并行、良好的可扩展性和理想加速比模型等优点,明显优于目前为止求解同类不对称线性规划问题的其他并行算法,可用于求解此类大规模线性规划问题的高性能计算.  相似文献   

18.
In this paper, we propose a real‐time algorithm for nonlinear receding horizon control using multiple shooting and the continuation/GMRES method. Multiple shooting is expected to improve numerical accuracy in calculations for solving boundary value problems. The continuation method is combined with a Krylov subspace method, GMRES, to update unknown quantities by solving a linear equation. At the same time, we apply condensing, which reduces the size of the linear equation, to speed up numerical calculations. A numerical example shows that both numerical accuracy and computational speed improve using the proposed algorithm by combining multiple shooting with condensing. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

19.
This paper considers the linear weighted complementarity problem (denoted by LWCP). We introduce a parametric smoothing function which is a broad class of smoothing functions for the LWCP and enjoys some favourable properties. Based on this function, we propose a new non-interior continuation method for solving the LWCP. In general, the non-interior continuation method consists of finding an exact solution of a system of equations at each iteration, which may be cumbersome if one is solving a large-scale problem. To overcome this difficulty, our method uses an inexact Newton method to solve the corresponding linear system approximately and adopts a non-monotone line search to obtain a step size. Under suitable assumptions, we show that the proposed method is globally and locally quadratically convergent. Preliminary numerical results are also reported.  相似文献   

20.
In this paper, an improved version of online continuation method controller for PWM systems is presented. The online continuation method controller solves the PWM-type deadbeat control problem numerically. By using this algorithm, iterations for solving the set of nonlinear equations always start from a good solution candidate and therefore it can be used online. The original continuation method is modified so that it is applicable to real systems. The validity of the proposed control method is demonstrated by a laboratory-scale flexible arm manipulator.  相似文献   

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