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1.
This paper investigates the completion and the zero prime factorization for matrices over a K-Hermite ring. The authors have generalized Kaplansky's related results, solved similar Lin-Bose problem and generalized Serre problem over a K-Hermite ring.  相似文献   

2.
By constructing a Gray map, a class of constacyclic codes over ring R = R+vR is studied. Using cyclic codes and negacyclic codes of length p s over ring R, the structure of (1?2v)-constacyclic codes and dual codes of length p s over ring R are given, the Gray images of (1 ? 2v)-constacyclic codes in a particular case are also studied. It is shown that linear codes of length p s over ring R are (1?2v)-constacyclic codes if and only if their Gray images are distance-invariant cyclic codes of length 2p s over ring R.  相似文献   

3.
基于动态广义直方图均衡的红外图像增强方法   总被引:1,自引:0,他引:1  
针对直方图均衡法进行红外图像增强时存在的问题,提出了动态广义直方图均衡方法。首先,广义直方图通过基于局部复杂度计算的分数值计数,体现了图像的不同区域特性,防止了过增强和放大噪声。然后,对广义直方图利用SG算法平滑滤波后,采用GK聚类算法实现对直方图的动态划分,避免高概率灰度背景对低概率灰度目标的影响。最后,动态分配目标和背景的输出灰度区间,突出目标细节,控制增强效果。实验结果表明,算法能有效克服传统直方图均衡法丢失目标细节、不能控制增强效果和过分放大噪声的不足,是一种有效的红外图像增强方法。  相似文献   

4.
针对传统滤波方法在α稳定分布噪声环境下性能退化的问题,从加权Myriad滤波以及加权Merid滤波方法出发,以M估计理论为基础,推导得到稳健加权(robust weighted,RW)滤波方法的统一算法结构,并据此提出了基于RW滤波的新算法,即基于稳健加权滤波的统一框架,从而将加权Myriad、加权Merid以及基于广义柯西分布的加权滤波器统一起来。此外,针对线性调频(linear frequency modulation, LFM)信号采用基于RW的LVD(RW LVD)方法估计其参数,并根据估计性能对RW方法的抑噪效果进行分析。仿真结果表明,与基于加权Myriad滤波、加权Merid滤波以及基于广义柯西分布的加权滤波等多种方法相比,在强脉冲噪声下RW滤波方法能有效抑制脉冲噪声,并具有良好的稳健性。  相似文献   

5.
对于多目标跟踪系统,滤波器的起始波门的设计是一个关键问题,首先给出了利用量测标准差与采样周期比值的相对大小来确定滤波器启始的方法,然后利用目标速度极限的先验信息构造环状波门,并考虑量测量噪声对环状波门的影响,利用矩阵范数特性,导出一种更精细的基于两点外推的滤波器启始法,仿真结果表明利用本文方法的构造出的波门的置信区间比其他两种方法所构作出的更为合理。  相似文献   

6.
PARALLEDOMAINDECOMPOSITIONALGORITHMSFORAGENERALIZEDSTOKESPROBLEM¥CHUDelin;ZHOUFangjun(DepartmentofAppliedMathematics,Tsinghua...  相似文献   

7.
It is one of the oldest research topics in computer algebra to determine the equivalence of Riemann tensor indexed polynomials. However, it remains to be a challenging problem since Grbner basis theory is not yet powerful enough to deal with ideals that cannot be finitely generated. This paper solves the problem by extending Grbner basis theory. First, the polynomials are described via an infinitely generated free commutative monoid ring. The authors then provide a decomposed form of the Grbner basis of the defining syzygy set in each restricted ring. The canonical form proves to be the normal form with respect to the Grbner basis in the fundamental restricted ring, which allows one to determine the equivalence of polynomials. Finally, in order to simplify the computation of canonical form, the authors find the minimal restricted ring.  相似文献   

8.
This paper deals with the problem of H∞ fault estimation for linear time-delay systems in finite frequency domain. First a generalized coordinate change is applied to the original system such that in the new coordinates all the time-delay terms are injected by the system’s input and output. Then an observer-based H∞ fault estimator with input and output injections is proposed for fault estimation with known frequency range. With the aid of Generalized Kalman-Yakubovich-Popov lemma, sufficient conditions on the existence of the H∞ fault estimator are derived and a solution to the observer gain matrices is obtained by solving a set of linear matrix inequalities. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.  相似文献   

9.
This paper introduces and considers a new system of generalized mixed variational inequalities in a Hilbert space,which includes many new and known systems of variational inequalities and generalized variational inequalities as special cases.By using the two concepts of 77-subdifferential andη-proximal mappings of a proper function,the authors try to demonstrate that the system of generalized mixed variational inequalities is equivalence with a fixed point problem.By applying the equivalence, a new and innovativeη-proximal point algorithm for finding approximate solutions of the system of generalized mixed variational inequalities will be suggested and analyzed.The authors also study the convergence analysis of the new iterative method under much weaker conditions.The results can be viewed as a refinement and improvement of the previously known results for variational inequalities.  相似文献   

10.
基于口令的身份认证机制是分布式系统安全体系的重要组成部分。利用一个无需求逆的广义椭圆曲线签名算法构造了一个动态远程用户认证方案:GECSA方案。该方案基于“质询响应”机制,无需时戳,其安全性基于单向Hash函数和椭圆曲线离散对数计算的困难性,包括注册阶段、登录阶段、认证阶段和更改口令阶段,允许用户自主选择并更改口令,实现了双向认证;具备完备性和不可转让性,是一个低开销的、安全的远程用户认证机制。  相似文献   

11.
具有多值映射的两级优化问题的广义算法研究   总被引:1,自引:0,他引:1  
两级优化问题是一种非凸非光滑问题,绝大多数问题的求解都是建立在下层有唯一解的基础之上的。而本文针对多值映射,即下层非唯一解的情形,利用隐函数理论,将两级优化问题转化为带有隐函数的非光滑问题,提出求解这类问题的广义算法框架,并证明其收敛性,最后通过实例验证该方法的实用性.  相似文献   

12.
针对指标间相关联的模糊多目标指派问题,引入广义模糊测度刻画指标间的关联,提出了基于广义模糊测度和Choquet积分的模糊权重信息集结算子,基于该算子给出了一种将模糊多目标指派问题转化为传统指派问题的算法.数值实验证明了该方法的可行性与有效性.  相似文献   

13.
A DYNAMIC OPTIMAL ADVERTISING MODEL FOR NEW PRODUCTS   总被引:2,自引:0,他引:2  
Many dynamic optimal control models for advertising make efforts to solve the problem of determining optimal advertising expenditures and other variables of interest over time for a firm or several competing firms,However,after analyzing the extant literature,one can find that few dynamic optimal advertising models available consider the problem within the product diffusion framework.Furthermore,the established models involving product diffusion are inspired by the Bass model,which has been out of date.This paper poses a dynamic optimal advertising model for new products,which considers the product diffusion based on the relative newly developed generalized version of the Bass model.In this paper,the optimal control model is used to derive the optimal advertising expenditure policy,which gives some implications to advertising practice.  相似文献   

14.
This paper deals with Henig globally efficiency in vector optimization involving generalized cone-preinvex set-valued mapping. Some properties of generalized cone-preinvex set-valued map are derived. It also disclose the closed relationships between Henig globally efficiency of generalized conepreinvex set-valued optimization problem and Henig globally efficiency of a kind of vector variational inequality.  相似文献   

15.
This paper obtains some stability results for parametric generalized set-valued weak vector equilibrium problem. Under new assumptions, which do not contain any information about solution mappings, the authors establish the continuity of the solution mapping to a parametric generalized set-valued weak vector equilibrium problem without monotonicity. These results extend and improve some results in the literature. Some examples are given to illustrate the results.  相似文献   

16.
Reliability is a desirable performance indicator of many real-world systems to measure the quality level. One general method for evaluating multi-state reliability is using d-minimal paths (d-MPs). However, being an NP-hard problem, searching for all d-MPs is a rather challenging task. This paper proposes an improved algorithm to solve the d-MP problem. To reduce the search space of d-MPs, a concept of lower capacity bound is introduced into the d-MP problem, and an effective technique is developed to find lower capacity bounds. Meanwhile, the fast enumeration method which is a recent improvement to the traditional enumeration method is employed to solve d-MPs. In addition, by introducing the operation of transforming undirected edges into directed edges, the proposed algorithm is applicable to solving both directed networks and undirected networks. Through numerical experiments, it is found that the proposed algorithm holds a distinct advantage over the existing methods in solving all d-MPs.  相似文献   

17.
具参数不确定性广义系统的保成本控制   总被引:8,自引:1,他引:7  
胡刚 《系统工程》2003,21(4):106-111
考虑一类具参数不确定性广义系统保成本控制器的设计问题。针对不确定连续广义系统,利用广义二次稳定的有关结果,首次提出广义二次保成本的概念,通过采用矩阵不等式方法.导出广义二次保成本的一个充要条件,并给出一个保成本控制器的设计方法。所举实例说明了本方法的有效性。  相似文献   

18.
针对广义变结构控制系统的抖振问题,给出了新的控制策略:动态软变结构控制。首先给出了软变结构控制定义和控制器构造形式。其次讨论了广义动态软变结构控制系统的稳定性,构造了合适的广义动态软变结构控制器,给出了动态软变结构控制的具体算法。所设计的动态软变结构控制是无滑模的变结构控制,调节精度高,响应速度快,有效地削弱了系统抖振,具有良好的动态品质。最后,用一个仿真实例验证了本文方法的可行性和有效性,展示了它进一步的发展前景。  相似文献   

19.
Minimax programming problems involving generalized (p, r)-invex functions are consid- ered. Parametric sufficient optimality conditions and duality results are established under the aforesaid assumptions on the objective and constraint functions.  相似文献   

20.
Path determination is a fundamental problem of operations research.Current solutions mainly focus on the shortest and longest paths.We consider a more generalized problem;specifically,we consider the path problem with desired bounded lengths(DBL path problem).This problem has extensive applications;however,this problem is much harder,especially for large-scale problems.An effective approach to this problem is equivalent simplification.We focus on simplifying the problem in acyclic networks and creating a path length model that simplifies relationships between various path lengths.Based on this model,we design polynomial algorithms to compute the shortest,longest,second shortest,and second longest paths that traverse any arc.Furthermore,we design a polynomial algorithm for the equivalent simplification of the DBL path problem.The complexity of the algorithm is 0(m),where m is the number of arcs.  相似文献   

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