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1.
为有效解决公租房退出问题,提出一种基于多源异构数据的模糊积分融合退出方法,该退出方法首先给出一种多源异构数据的同构化方法,然后针对常用模糊测度确定方法原理复杂、计算困难的问题,提出一种原理简单、易于计算的模糊测度确定方法,该模糊测度确定方法利用单个属性的相对重要程度和两两属性之间的交互度计算单个属性的全局重要程度,最后,根据模糊测度的单调性和有界性通过专家逐级打分计算各子属性集的重要程度。实例验证表明所提出的退出方法可行、有效。  相似文献   

2.
研究多粒度语言群决策中群体意见一致性问题.根据群体决策中多粒度语言的基本特征,提出一种基于隶属度分布函数的一致性测度计算方法.并且与基于二元语义的决策的一致性测度计算方法进行了比较,通过算例计算分析,说明了该方法的可行性和有效性.  相似文献   

3.
复测度鞅空间及其对偶   总被引:3,自引:0,他引:3  
侯友良  刘培德 《数学学报》1997,40(4):481-492
本文在Ψ满足(K)条件或   的条件下,讨论了关于复测度dμ=Ψdv的鞅空间    和aK_p.证明了它们之间的等价性以及与关于非负测度dv的相应鞅空间的同构性,给出了它们的对偶空间,特别地H1=BMO,最后证明了关于复测度软的均方算子S(f)是弱(1,1)有界的。  相似文献   

4.
在犹豫模糊集上提出一种新的距离测度。值得指出的是新距离测度不需要给长度较短的犹豫模糊元添加元素来保证不同的犹豫模糊元长度相同。研究了新距离测度的一些性质并证明了新距离测度不仅满足三角不等式而且满足单调性。进一步,通过实例说明新距离测度是有效的和实用的  相似文献   

5.
不变测度及其计算   总被引:4,自引:0,他引:4  
用统计方法研究混沌动力系统时需要藉助不变测度理论.本文通过引进Frobenius-Peron算子,概述了一类绝对连续不变测度的存在条件与计算现状  相似文献   

6.
模糊熵与距离测度的相互诱导及其应用   总被引:2,自引:0,他引:2  
模糊信息论就是利用模糊数学这一工具来研究带有模糊不确定性的信息的.模糊熵和距离测度是模糊信息论中两个重要的度量方法.本文主要讨论模糊熵和距离测度之间的相互关系,由此得到几个由模糊熵诱导的距离测度公式和几个由距离测度诱导出的模糊熵公式,说明了模糊熵和距离测度是可以相互诱导的.最后,举例说明距离测度公式在模式识别中的应用.  相似文献   

7.
针对准则值为概率语言术语集的决策问题,提出一种基于共识性测度的概率语言多准则群决策方法.首先,方法定义概率语言共识性测度公式,据此判断个体决策信息是否满足共识性检验.其次,建立考虑决策者协作意愿的群体共识反馈调整模型及权重惩罚体系.此外,利用网络层次分析法(ANP)和共识性测度公式构建指标定权模型,模型可有效解决指标间互相影响导致的权重计算失准问题.随后,提出改进的TODIM决策方法,结合准则权系数及通过共识性检验的群决策矩阵,对方案进行择优排序.最后,通过算例分析验证了该方法的有效性.  相似文献   

8.
针对现有犹豫模糊语言距离测度存在不满足直递性、改变了原始决策信息、忽略了犹豫度差异等方面的问题,提出了一系列更为合理的新型犹豫模糊语言距离测度方法。首先,对现有犹豫模糊语言距离测度的局限性进行了枚举和分析。其次,给出了犹豫模糊语言犹豫度的定义,分别提出了犹豫模糊语言集的Euclidean距离、Hamming距离、Hamming-Hausdorff距离、Euclidean-Hausdorff距离以及它们的广义形式、加权形式和广义加权形式等一系列新型犹豫模糊语言距离测度,并对新型犹豫模糊语言距离测度的相关性质和定理进行了证明。在此基础上,提出了一种基于新型犹豫模糊语言距离测度和离差最大化的多属性决策方法。最后,通过具体算例和对比分析验证了新型犹豫模糊语言距离测度和多属性决策方法的可行性和有效性。  相似文献   

9.
基于对偶犹豫模糊集的定义,首先由对偶犹豫模糊集距离测度的定义,给出了对偶犹豫模糊集的Hamming距离测度公式。其次给出了一个最优化模型来计算完全未知的属性权重。最后提出了以便用来度量两个对偶犹豫模糊信息之间相关关系的相关系数,并给出定义和加权相关系数计算公式,使决策运算更快捷有效。由此提出一种属性权重完全未知的模糊多属性决策方法,并给出此方法的计算步骤,通过实例验证了该方法的有效性。  相似文献   

10.
研究了函数和集在某点的邻近正则性与次微分连续性,给出邻近正则函数的次微分在某种意义下的单调性及函数的邻近正则性与其上图的邻近正则性的关系.  相似文献   

11.
We tackle the problem of computing the Voronoi diagram of a 3-D polyhedron whose faces are planar. The main difficulty with the computation is that the diagram's edges and vertices are of relatively high algebraic degrees. As a result, previous approaches to the problem have been non-robust, difficult to implement, or not provenly correct.

We introduce three new proximity skeletons related to the Voronoi diagram: (1) the Voronoi graph (VG), which contains the complete symbolic information of the Voronoi diagram without containing any geometry; (2) the approximate Voronoi graph (AVG), which deals with degenerate diagrams by collapsing sub-graphs of the VG into single nodes; and (3) the proximity structure diagram (PSD), which enhances the VG with a geometric approximation of Voronoi elements to any desired accuracy. The new skeletons are important for both theoretical and practical reasons. Many applications that extract the proximity information of the object from its Voronoi diagram can use the Voronoi graphs or the proximity structure diagram instead. In addition, the skeletons can be used as initial structures for a robust and efficient global or local computation of the Voronoi diagram.

We present a space subdivision algorithm to construct the new skeletons, having three main advantages. First, it solves at most uni-variate quartic polynomials. This stands in sharp contrast to previous approaches, which require the solution of a non-linear tri-variate system of equations. Second, the algorithm enables purely local computation of the skeletons in any limited region of interest. Third, the algorithm is simple to implement.  相似文献   


12.
根据灰度图像的二维直方图的特点,在已有的二维Arnold混沌系统的基础上,结合Bernstein形式的Bézier曲线的生成算法,给出了一种基于生成Bézier曲线的de Casteljau算法构造伪随机序列的方法,实验结果表明生成的二维序列不仅具有伪随机性,而且还具有在近似圆盘中随机分布的性质,这使得该伪随机序列更适合对灰度图像的二维灰度直方图进行基于混沌优化的图像分割.在此基础上,给出了一种基于混沌优化的二维最大熵的灰度图像分割算法,该算法对于含噪图像取得了良好的分割效果.  相似文献   

13.
Many methods to compute the winding number of plane curves have been proposed, often with the aim of counting the number of roots of polynomials (or, more generally, zeros of analytic functions) inside some region by using the principle of argument. In this paper we propose another method, which are not based on numerical integration, but on discrete geometry. We give conditions that ensure its correct behavior, and a complexity bound based on the distance of the curve to singular cases. Besides, we provide a modification of the algorithm that detects the proximity to a singular case of the curve. If this proximity is such that the number of operations required grows over certain threshold, set by the user, the modified algorithm returns without winding number computation, but with information about the distance to singular case. When the method is applied to polynomials, this information refers to the localization of the roots placed near the curve.  相似文献   

14.
Binarization is an important basic operation in image processing community. Based on the thresholded value, the gray image can be segmented into a binary image, usually consisting of background and foreground. Given the histogram of input gray image, based on minimizing the within-variance (or maximizing the between-variance), the Otsu method can obtain a satisfactory binary image. In this paper, we first transfer the within-variance criterion into a new mathematical formulation, which is very suitable to be implemented in a fast incremental way, and it leads to the same thresholded value. Following our proposed incremental computation scheme, an efficient heap- and quantization-based (HQ-based) data structure is presented to realize its implementation. Under eight real gray images, experimental results show that our proposed HQ-based incremental algorithm for binarization has 36% execution-time improvement ratio in average when compared to the Otsu method. Besides this significant speedup, our proposed HQ-based incremental algorithm can also be applied to speed up the Kittler and Illingworth method for binarization.  相似文献   

15.
基于邻近度量函数的最小值,对P*(κ)阵线性互补问题提出了一种新的宽邻域预估-校正算法,在较一般的条件下,证明了算法的迭代复杂性为O(κ+1)23n log(x0ε)Ts0.算法既可视为Miao的P*(κ)阵线性互补问题Mizuno-Todd-Ye预估-校正内点算法的一种变形,也可以视为最近Zhao提出的线性规划基于邻近度量函数最小值的宽邻域内点算法的推广.  相似文献   

16.
Recently, optimization algorithms for solving a minimization problem whose objective function is a sum of two convex functions have been widely investigated in the field of image processing. In particular, the scenario when a non-differentiable convex function such as the total variation (TV) norm is included in the objective function has received considerable interests since many variational models encountered in image processing have this nature. In this paper, we propose a fast fixed point algorithm based on the adapted metric method, and apply it in the field of TV-based image deblurring. The novel method is derived from the idea of establishing a general fixed point algorithm framework based on an adequate quadratic approximation of one convex function in the objective function, in a way reminiscent of Quasi-Newton methods. Utilizing the non-expansion property of the proximity operator we further investigate the global convergence of the proposed algorithm. Numerical experiments on image deblurring problem demonstrate that the proposed algorithm is very competitive with the current state-of-the-art algorithms in terms of computational efficiency.  相似文献   

17.
大规模离散元的并行计算通常基于理想的球体单元,然而自然界或工业生产中普遍存在的是由非球形颗粒组成的复杂体系,其在不同空间尺度下的动力学行为及力学性质与球形颗粒具有显著差异.基于连续函数包络的超二次曲面单元能有效地构造非球形颗粒的几何形态,并通过非线性Newton迭代算法准确计算单元间的作用力.针对非球形颗粒间接触判断的复杂性及其大规模离散元计算的需求,该文发展了基于CUDA-GPU构架下超二次曲面单元并行算法.该方法在球形颗粒并行计算的基础上,通过核函数建立单元包围盒的粗判断列表及Newton迭代的细判断列表,并优化并行算法和内存访问模式以提高算法的计算效率.为检验超二次曲面并行算法的可靠性,对非球形颗粒的流动过程进行离散元模拟, 并与试验结果进行对比验证.在此基础上,进一步分析了颗粒单元不同长宽比和表面尖锐度对颗粒材料流动特性的影响,为非球形颗粒材料的大规模离散元模拟提供一种有效的数值方法.  相似文献   

18.
Our work considers the optimization of the sum of a non-smooth convex function and a finite family of composite convex functions, each one of which is composed of a convex function and a bounded linear operator. This type of problem is associated with many interesting challenges encountered in the image restoration and image reconstruction fields. We developed a splitting primal-dual proximity algorithm to solve this problem. Furthermore, we propose a preconditioned method, of which the iterative parameters are obtained without the need to know some particular operator norm in advance. Theoretical convergence theorems are presented. We then apply the proposed methods to solve a total variation regularization model, in which the L2 data error function is added to the L1 data error function. The main advantageous feature of this model is its capability to combine different loss functions. The numerical results obtained for computed tomography (CT) image reconstruction demonstrated the ability of the proposed algorithm to reconstruct an image with few and sparse projection views while maintaining the image quality.  相似文献   

19.
申远  李倩倩  吴坚 《计算数学》2018,40(1):85-95
本文考虑求解一种源于信号及图像处理问题的鞍点问题.基于邻近点算法的思想,我们对原始-对偶算法进行改进,构造一种对称正定且可变的邻近项矩阵,得到一种新的原始-对偶算法.新算法可以看成一种邻近点算法,因此它的收敛性易于分析,且无需较强的假设条件.初步实验结果表明,当新算法被应用于求解图像去模糊问题时,和其他几种主流的高效算法相比,新算法能得到较高质量的结果,且计算时间也是有竞争力的.  相似文献   

20.
The Weiszfeld algorithm for continuous location problems can be considered as an iteratively reweighted least squares method. It generally exhibits linear convergence. In this paper, a Newton algorithm with similar simplicity is proposed to solve a continuous multifacility location problem with the Euclidean distance measure. Similar to the Weiszfeld algorithm, the main computation can be solving a weighted least squares problem at each iteration. A Cholesky factorization of a symmetric positive definite band matrix, typically with a small band width (e.g., a band width of two for a Euclidean location problem on a plane) is performed. This new algorithm can be regarded as a Newton acceleration to the Weiszfeld algorithm with fast global and local convergence. The simplicity and efficiency of the proposed algorithm makes it particularly suitable for large-scale Euclidean location problems and parallel implementation. Computational experience suggests that the proposed algorithm often performs well in the absence of the linear independence or strict complementarity assumption. In addition, the proposed algorithm is proven to be globally convergent under similar assumptions for the Weiszfeld algorithm. Although local convergence analysis is still under investigation, computation results suggest that it is typically superlinearly convergent.  相似文献   

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