共查询到19条相似文献,搜索用时 78 毫秒
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提出非线性等式和有界约束优化问题的结合非单调技术的仿射信赖域方法.
结合信赖域方法和内点回代线搜索技术, 每一步迭代转到由一般信赖域子问题产生的回代步中且满足严格内点可行条件.
在合理的假设条件下, 证明了算法的整体收敛性和局部超线性收敛速率.
最后, 数值结果表明了所提供的算法具有有效性. 相似文献
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非线性规划的序列仿射尺度投影内点算法 总被引:2,自引:0,他引:2
本文提出了求解非线性规划的一种序列二次规划内点算法,与其他算法的不同之处在于引进了仿射尺度变换,且避免了一维搜索,这使得该算法的计算量获得了明显的减少,本文给出了算法的详细迭代步骤并讨论了算法的收敛性。 相似文献
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Shearlet框架的构造和图像处理 总被引:1,自引:0,他引:1
本文指出了频域划分和拓扑群之间的联系,给出了构造shearlet框架的一般方法,并具体地构造出了-个衰减性良好的shearlet函数.在数值计算方面,本文提出了框架系数的计算方法和基于此方法的图像重构算法.最后的数值实验说明本文构造的shearlet在图像重构方面表现良好. 相似文献
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提出了结合仿射尺度技术的正割算法解非线性等式与有界约束优化问题.
在合理假设下, 证明了渐弱滤子线搜索方法可以保证新算法具有整体收敛性.
通过引入一个高阶修正方向, 克服Maratos效应的影响, 使得算法二步$q$-\!\!超线性收敛于最优点.
进一步地, 对算法进行修改, 使得新算法达到$q$-\!\!超线性收敛性. 相似文献
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对于道路网络聚类问题,提出了仿射传播算法。首先,将道路网络上的交叉路口和结点作为顶点,建立了无向图;然后,根据最短路径计算网络距离,进而得到图的相似度矩阵;并基于仿射传播算法对道路网络进行聚类;最后,试验结果证实了本文方法的有效性与稳定性。 相似文献
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提供了一种新的非单调内点回代线搜索技术的仿射内点信赖域方法解线性不等式约束的广义非线性互补问题(GCP).基于广义互补问题构成的半光滑方程组的广义Jacobian矩阵,算法使用l2范数作为半光滑方程组的势函数,形成的信赖域子问题为一个带椭球约束的线性化的二次模型.利用广义牛顿方程计算试探迭代步,通过内点映射回代技术确保迭代点是严格内点,保证了算法的整体收敛性.在合理的条件下,证明了信赖域算法在接近最优点时可转化为广义拟牛顿步,进而具有局部超线性收敛速率.非单调技术将克服高度非线性情况加速收敛进展.最后,数值结果表明了算法的有效性. 相似文献
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提供了一种新的非单调内点回代线搜索技术的仿射内点信赖域方法解线性不等式约束的广义非线性互补问题(GCP).基于广义互补问题构成的半光滑方程组的广义Jacobian矩阵,算法使用l_2范数作为半光滑方程组的势函数,形成的信赖域子问题为一个带椭球约束的线性化的二次模型.利用广义牛顿方程计算试探迭代步,通过内点映射回代技术确保迭代点是严格内点,保证了算法的整体收敛性.在合理的条件下,证明了信赖域算法在接近最优点时可转化为广义拟牛顿步,进而具有局部超线性收敛速率.非单调技术将克服高度非线性情况加速收敛进展.最后,数值结果表明了算法的有效性. 相似文献
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Ning ZHANG~ 《中国科学A辑(英文版)》2007,50(7):941-950
This paper discusses two problems:one is some important theories and algorithms of affine bracket algebra;the other is about their applications in mechanical theorem proving.First we give some efficient algorithms including the boundary expanding algorithm which is a key feature in application.We analyze the characteristics of the boundary operator and this is the base for the implementation of the system.We also give some new theories or methods about the exact division,the representations and structure of affine geometry and so on.In practice,we implement the mechanical auto-proving system in Maple 10 based on the above algorithms and theories.Also we test about more than 100 examples and compare the results with the methods before. 相似文献
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A new trust-region and affine scaling algorithm for linearly constrained optimization is presented in this paper. Under no
nondegenerate assumption, we prove that any limit point of the sequence generated by the new algorithm satisfies the first
order necessary condition and there exists at least one limit point of the sequence which satisfies the second order necessary
condition. Some preliminary numerical experiments are reported.
The work was done while visiting Institute of Applied Mathematics, AMSS, CAS. 相似文献
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In this paper we undertake a systematic investigation of affine invariant object detection and image denoising. Edge detection is first presented from the point of view of the affine invariant scale-space obtained by curvature based motion of the image level-sets. In this case, affine invariant maps are derived as a weighted difference of images at different scales. We then introduce the affine gradient as an affine invariant differential function of lowest possible order with qualitative behavior similar to the Euclidean gradient magnitude. These edge detectors are the basis for the extension of the affine invariant scale-space to a complete affine flow for image denoising and simplification, and to define affine invariant active contours for object detection and edge integration. The active contours are obtained as a gradient flow in a conformally Euclidean space defined by the image on which the object is to be detected. That is, we show that objects can be segmented in an affine invariant manner by computing a path of minimal weighted affine distance, the weight being given by functions of the affine edge detectors. The gradient path is computed via an algorithm which allows to simultaneously detect any number of objects independently of the initial curve topology. Based on the same theory of affine invariant gradient flows we show that the affine geometric heat flow is minimizing, in an affine invariant form, the area enclosed by the curve. 相似文献
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In this paper, we propose an infeasible-interior-point algorithm for linear programning based on the affine scaling algorithm by Dikin. The search direction of the algorithm is composed of two directions, one for satisfying feasibility and the other for aiming at optimality. Both directions are affine scaling directions of certain linear programming problems. Global convergence of the algorithm is proved under a reasonable nondegeneracy assumption. A summary of analogous global convergence results without any nondegeneracy assumption obtained in [17] is also given. 相似文献
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提供了一类新的结合非单调内点回代线搜索技术的仿射变换Levenberg-Marquardt法解Karush-Kuhn-Tucker(KKT)系统. 基于由KKT系统转化得到的等价的部分变量具有非负约束的最小化问题,建立了Levenberg-Marquardt方程. 证明了算法不仅具有整体收敛性,而且在合理的假设条件下,算法具有超线性收敛速率. 数值结果验证了算法的实际有效性. 相似文献
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分组峦码是现代密码学中一个重要的研究分支,而置换理论在分组密码中有重要的地位.199j年,美国Tcledyne电子技术公司的Lothrop Mittenthal博士提出了一种置换,即正形置换.止形置换是一类完全映射,完全映射是由Mann在1942年研究正交拉丁方的构造时引入的,其具有良好的密码学性质(良好的扩散性和完令平衡性),因此,正形置换常用来构造密码系统的算法,研究正形置换也就非常订必要.本文根据文章[1]的方法讨论了F2^n(n=4,5)上的4次正形置换多项式的形式与计数,至于n〉5的情形我们将在以后的篇章中继续讨论. 相似文献
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In this paper, we introduce the notion of partial affine system that is a subset of an affine system. It has potential applications in signal analysis. A general affine system has been extensively studied; however, the partial one has not. The main focus of this paper is on partial affine system–based frames and dual frames. We obtain a necessary condition and a sufficient condition for a partial affine system to be a frame and present a characterization of partial affine system–based dual frames. Some examples are also provided. 相似文献
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This paper is concerned with the solution of the nonlinear least squares problems. A new secant method is suggested in this paper, which is based on an affine model of the objective function and updates the first-order approximation each step when the iterations proceed. We present an algorithm which combines the new secant method with Gauss-Newton method for general nonlinear least squares problems. Furthermore, we prove that this algorithm is Q-superlinearly convergent for large residual problems under mild conditions. 相似文献