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71.
A tolerance region is a map from the sample space of one statistical model to the event space of a second statistical model having the same parameter. This paper derives an optimum β-expectation tolerance region for the multivariate regression model. A measure of power is proposed and evaluated.  相似文献   
72.
Let T be a homogeneous tree of homogeneity q+1. Let denote the boundary of T, consisting of all infinite geodesics b=[b 0,b 1,b 2,] beginning at the root, 0. For each b, 1, and a0 we define the approach region ,a (b) to be the set of all vertices t such that, for some j, t is a descendant of b j and the geodesic distance of t to b j is at most (–1)j+a. If >1, we view these as tangential approach regions to b with degree of tangency . We consider potentials Gf on T for which the Riesz mass f satisfies the growth condition T f p (t)q –|t|<, where p>1 and 0<<1, or p=1 and 0<1. For 11/, we show that Gf(s) has limit zero as s approaches a boundary point b within ,a (b) except for a subset E of of -dimensional Hausdorff measure 0, where H (E)=sup>0inf i q –|t i|:E a subset of the boundary points passing through t i for some i,|t i |>log q (1/).  相似文献   
73.
一种基于正负差图像的运动目标检测新方法   总被引:1,自引:1,他引:1       下载免费PDF全文
运动目标检测领域中现有的差图像法是利用绝对值差图像检测差图像上运动目标区域,用现有方法检测时易受噪声干扰,而且当摄像机有自运动时需要进行背景运动补偿。因此,提出一种新算法,即首先分别计算正差图像与负差图像,然后利用运动目标区域在正差图像与负差图像中的幅值、形状以及运动等信息的对称性对其进行检测,最后给出针对飞机尾焰序列图像进行检测的结果。实验结果表明:该方法可提高运动目标检测的可靠性与效率。  相似文献   
74.
Research into microdisk lasers demonstrates new achievements both in the technology and in the associated physical effects and applications. Melting and rounding of the disk edge boosts the Q-factors due to improved surface smoothness. In-plane cavity shape is widely used as a design instrument. Optimal shaping of pumped area lowers the threshold power. Photonic molecules made of several microdisks as “photonic atoms” show lasing at several closely spaced frequencies. A microdisk with a single quantum dot as an active region is considered as the most promising system for realisation of a single photon emitter necessary for quantum computing. These new effects and devices can be simulated with accurate numerical techniques, developed recently for “warm-cavity” linear modelling, that are able to bring a new vision of the physics of lasing.  相似文献   
75.
再入飞行器驻点流光辐射特性的理论建模   总被引:1,自引:0,他引:1  
本文用直接模拟蒙特卡罗法,对再入体驻点区域的流场、光辐射特性进行了研究.针对头部锥体驻点区(包括激波层),建立了流场中的化学反应模型,中性粒子和等离子体的热运动、粒子间碰撞的理论模型,碰撞激发辐射和化学发光辐射的物理模型.给出了样本粒子运动方向和速率、粒子碰撞对的选择等蒙特卡罗法概率模型和计算方法.  相似文献   
76.
Expressions are derived for the tunnel electric current between two metals produced by the adiabatic transitions of the electrons through a bridge electron level. A new possible physical phenomenon is discussed, viz. electronically driven oscillations of the electron bridge level between two molecular wires.  相似文献   
77.
Digital image correlation (DIC) has received a widespread research and application in experimental mechanics. In DIC, the performance of subpixel registration algorithm (e.g., Newton-Raphson method, quasi-Newton method) relies heavily on the initial guess of deformation. In the case of small inter-frame deformation, the initial guess could be found by simple search scheme, the coarse-fine search for instance. While for large inter-frame deformation, it is difficult for simple search scheme to robustly estimate displacement parameters and deformation parameters simultaneously with low computational cost. In this paper, we proposed three improving strategies, i.e. Q-stage evolutionary strategy (T), parameter control strategy (C) and space expanding strategy (E), and then combined them into three population-based intelligent algorithms (PIAs), i.e. genetic algorithm (GA), differential evolution (DE) and particle swarm optimization (PSO), and finally derived eighteen different algorithms to calculate the initial guess for qN. The eighteen algorithms were compared in three sets of experiments including large rigid body translation, finite uniaxial strain and large rigid body rotation, and the results showed the effectiveness of proposed improving strategies. Among all compared algorithms, DE-TCE is the best which is robust, convenient and efficient for large inter-frame deformation measurement.  相似文献   
78.
Based on a differentiable merit function proposed by Taji et al. in "Math. Prog. Stud., 58, 1993, 369-383", the authors propose an affine scaling interior trust region strategy via optimal path to modify Newton method for the strictly monotone variational inequality problem subject to linear equality and inequality constraints. By using the eigensystem decomposition and affine scaling mapping, the authors form an affine scaling optimal curvilinear path very easily in order to approximately solve the trust region subproblem. Theoretical analysis is given which shows that the proposed algorithm is globally convergent and has a local quadratic convergence rate under some reasonable conditions.  相似文献   
79.
In this paper, the gluon propagator in Landau gauge has been studied on a lattice, including the quenched and the unquenched one. The small geometry size of lattice we use is 16^3 × 32, and the big one is 20^3 × 64. For the quenched approximation, we fit the numerical results and give a little different fitting values. We also obtain unquenched effects by comparing the gluon propagator resulting from the quenched and unquenched configurations, for both the two-flavor and three-flavor cases. For the unquenched configurations, an obvious quark mass dependence has not been found in the small quark mass case, but is found in the three-flavor case when the quark mass is big.  相似文献   
80.
衢州市拥有龙游“小南海”,江山江郎山,市区孔庙和料柯山等景点,于是浙江省旅游局在《浙江省旅游业1998~2003年发展规划及2004~2010年发展 》中提出以市区(文化旅游区)为中心,龙游、江山(山水旅游区)为两翼的旅游业布局和建设的设想,这思路刘对头的。但是,常山和开化县还有丰富的动植物资源,诸如衢桔、胡柚、龙顶茶叶以及古田山自然保护区的多种珍稀动植物,根据旅游业发展。  相似文献   
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