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1.
提出了一种全自动、多模态的信息融合解决方案用于配准视频图像和磁跟踪数据。该配准方案将用于内窥镜图像的三维数字成像系统以对人体的三维解剖结构的外观和尺度进行重建,特别是用于微创手术。多模态标定方法如下:首先医生将磁跟踪器插入并固定于内窥镜的工作通道;然后利用该器械组对一个棋盘格模板的各个视角进行若干秒的采集;内窥镜坐标和磁跟踪器坐标的相对关系(平移和旋转)就可以立刻得到。在手术过程中,磁跟踪器显示的读数将可以自动用来推算出内窥镜的坐标(位置和朝向),并有利于重建器官的三维结构。虽然目前已有一些深入研究的算法用于从图像中推算相机的运动,他们通常非常容易受到图像分析、误差积累、结构形变等的影响。从实验结果分析可知,该方案提出使用磁跟踪器推算相机运动参数的方法可行且提高了精度。此外,该方法不需要特殊的训练或者昂贵的设备。  相似文献   

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基于灭点理论和平面控制场的相机标定方法研究   总被引:3,自引:0,他引:3       下载免费PDF全文
给出了一种基于灭点理论和平面控制场的相机解析自标定方法。在系统分析平面场景灭点几何的基础上,依据灭点理论并结合2维场景的共线方程严密论证和推导了平面控制场中相机外方位元素初值的实用算法。给出了一种圆形标志点的快速检测及定位方法,提出了一种基于计算可靠性矩阵QVVP的自检校光束法平差中各类观测值权值的确定方法。实验证明了该相机标定方法的正确性和有效性,为相机标定探索了一种可行的方法。  相似文献   

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In this paper, the minimization of a weighted total variation regularization term (denoted TV g ) with L 1 norm as the data fidelity term is addressed using the Uzawa block relaxation method. The unconstrained minimization problem is transformed into a saddle-point problem by introducing a suitable auxiliary unknown. Applying a Uzawa block relaxation method to the corresponding augmented Lagrangian functional, we obtain a new numerical algorithm in which the main unknown is computed using Chambolle projection algorithm. The auxiliary unknown is computed explicitly. Numerical experiments show the availability of our algorithm for salt and pepper noise removal or shape retrieval and also its robustness against the choice of the penalty parameter. This last property is useful to attain the convergence in a reduced number of iterations leading to efficient numerical schemes. The specific role of the function g in TV g is also investigated and we highlight the fact that an appropriate choice leads to a significant improvement of the denoising results. Using this property, we propose a whole algorithm for salt and pepper noise removal (denoted UBR-EDGE) that is able to handle high noise levels at a low computational cost. Shape retrieval and geometric filtering are also investigated by taking into account the geometric properties of the model.  相似文献   

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The structural transformation and transformation kinetics of Sb x Se100−x films (60 ≤ x ≤ 70) were studied to investigate the feasibility of applying Sb x Se100−x alloys in phase-change nonvolatile memories. The temperature-dependent van der Pauw measurements, Hall measurements, X-ray diffraction and a static tester were used to investigate the electrical properties and crystallization behavior of the Sb x Se100−x films. The sheet resistance difference between amorphous and crystalline state was higher than 104 Ω per square According to Hall measurement, Sb x Se100−x films have p-type conduction and the Hall mobility and carrier concentration increases with the increase in Sb content. The crystalline structure of the metastable phase of Sb x Se100−x alloys, which plays a major roll in fast crystallization, is similar to that of Sb2Te (rhombohedral structure). The transition temperature, sheet resistance and activation energy for transformation decrease as the amount of Sb increases in the Sb x Se100−x film. Applying the Kissinger method, the activation energies for crystallization were in the range from 1.90 ± 0.15 to 4.16 ± 0.28 eV. The desired crystallization speed can be obtained by a systematic change of the composition owing to the variation of the activation barrier with stoichiometry.  相似文献   

5.
A method for estimating a Lipschitz constant of the entropy operator of the Boltzmann type is suggested. Examples of the use of the obtained estimates in problems for restoring images by projections are given.__________Translated from Avtomatika i Telemekhanika, No. 7, 2005, pp. 54–65.Original Russian Text Copyright © 2005 by Popkov, Rublev.This work was supported by the Program “Branch of Information Technologies and Computer Systems” and the Russian Foundation for Basic Research, project no. 02-01-00198a.  相似文献   

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The method is suggested for the investigation of the existence, uniqueness, and localization of singular points of the DSEO class under consideration. The stability conditions are found “in the small” and “in the large.” Examples of the use of the obtained conditions are given.  相似文献   

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The object of the present paper is the investigation and study of (fuzzy) hyperideals in H v - semigroups. Regular equivalence relations play in H v - semigroup theory a role analogous to congruences in semigroup theory, so we introduce fuzzy regular equivalence relations on H v -semigroups and then we study fuzzy Rees regular relations on H v -semigroups. Using this ideas, we establish a relation between fuzzy hyperideal of an H v -semigroup H and fuzzy hyperideal of a quotient H v -semigroup of H. Some characterizations of them are then shown.   相似文献   

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提出了一种新的基于DCT域的MPEG-2码流转换算法,该算法与现有算法,即通过解码、空域采样率转换来设定新的码流参数,再编码的算法相比,无需IDCT、DCT操作,便可在DCT域实现码流转换,而且省去了运动矢量估值和运动补偿过程,不仅节省了大量帧存和减少了运算量,而且更具有实时性的优点,对MPEG-2 MP@ML到4:2:2Profile@ML码流转换算法实例的分析和现实表明:该算法能简单有效的实现压缩域码流转换,其思想同样可广泛用于其他基于DCT压缩图象的采样率转换、线性滤波等任务。  相似文献   

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In dieser Arbeit wird anhand von zwei konkreten Beispielen erl?utert, was Wissensmanagement (WM) ist und warum WM eine so wichtige Rolle in der Zukunft spielen wird. Dies gilt freilich nur, wenn es sich bei WM um mehr handelt als die Verwendung von Informationssystemen oder verteilten Datenbanken für anspruchsvolle Aufgaben.  相似文献   

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为分析高次多项式动力凸轮型线的特性参数对配气机构性能的影响,以某高速汽油机双顶置凸轮轴配气系统为研究对象,基于配气机构运动学和动力学计算理论,建立高次多项式动力凸轮型线的数学模型.在AVL-TYCON中建立运动学和动力学仿真模型,计算并分析丰满因数、正加速脉冲宽度和润滑因数等关键评价指标的变化规律,结果表明:随着各阶幂指数的增大,丰满因数逐渐增加,发动机获得较好的充气性能,但正加速度宽度逐渐减小,配气机构工作平稳性变差.  相似文献   

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为了在激烈的竞争中获取利润,一些商业欺诈现象泛滥成灾,不但未能受到遏制反而因技术的现代化而愈趋隐蔽。以低质低价的产品混充优质产品在一些业主看来似乎永远是一条致富的捷径。如果说设计艺术不单纯是为了美化我们的生活,更重要的是要提高我们日常生活的质量的话,那么,设计师就有义务推动和促进公平交易的实现。  相似文献   

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电力产业是国民工业系统中重要的产业。在电网运行管理中,对于负荷预测具有非常重要的作用。更加准确的电力负荷预测可以为电网的安全稳定运行、实时进行电网负荷的调度提供了重要依据。特别是在经济方面,精确的电力负荷预测可以优化发、用电电网调度计划,合理调度和分配资源,从而起到使社会效益、经济效益最大化的作用。然而随着中国经济的飞速发展,对电力的需求不断增长,电力负荷本身受诸多因素以及政策影响比如日期、天气、气候、市场等其他因素,这些因素更大大加大了准确进行电力负荷预测的困难性。一直以来,人们一直都致力于提高电力负荷预测的准确性,人工神经网络算法具有泛化、学习能力强等优点,现在该算法已在电力负荷预测领域中得到了广泛应用,并且取得了良好的效果。近年来,人工神经网络领域取得重大突破,涌现出一个新的深度学习研究领域。本文就是基于最新发展的人工神经网络算法,结合实际地区电网数据研究了短期电力负荷预测的相关问题。  相似文献   

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Given a closed, convex set X\subseteq \bbR n , containing the origin, we consider the problem (P) : max {c^\T x\colon x ∈ X} . We show that, for a fixed dimension, n , and fixed \eps , 0 <\eps<1 , the existence of a combinatorial, strongly polynomial \eps -approximation separation algorithm for the set X is equivalent to the existence of a combinatorial, strongly polynomial \eps -approximation optimization algorithm for the problem (P) . Received June 5, 1996; revised September 25, 1997.  相似文献   

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This paper generalizes the standard long memory modeling by assuming that the long memory parameter d is stochastic and time-varying: we introduce a STAR process on this parameter characterized by a logistic function. We propose an estimation method of this model. Some simulation experiments are conducted. The empirical results suggest that this new model offers an interesting alternative competing framework to describe the persistent dynamics in modeling some financial series.   相似文献   

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