一种分区域多方向数据融合图像插值方法

为满足高端工业检测中对检测精度和检测时间的严格要求,针对现有图像插值方法在插值速度与精度方面的矛盾,本文提出了一种分区域多方向数据融合图像插值方法。在灰度平坦区域,采用双线性插值算法进行插值。在边缘纹理区域,则选取待插值点在源图像中对应点的4×4邻域内4个插值方向上距离最近的12个像素点,基于距离平方反比计算估计值;然后结合方向灰度梯度和插值距离两个权 重因子,进行数据融合,获得最终插值。实验表明,新提出的插值方法运行速度快,并且在图像任意级别变换时都具有较高的插值精度,能够很好地保持图像的边缘纹理细节。     

基于块稀疏快速重构的MISO活跃用户集与信道联合估计

针对多用户多输入单输出（Multiple input single output, MISO)系统的用户选择与信道估计问题,引入基于用户分布式自选择的信道接入策略,设计一种新的结合该策略的时分双分复用（Time division duplex, TDD)模式数据传输帧结构。利用用户活跃模式自然稀疏性和信道冲激响应时延域稀疏性,将基站接收上行随机导频序列建模为块稀疏线性模型。基于凸松弛的l2/l1模型提出一种快速的块稀疏重构算法求解问题模型。算法首先对目标函数进行变量分裂,然后利用交替方向法对各变量进行交替更新,直至满足收敛条件。交替更新中,对于无法获得闭式解的信号变量项,采取块坐标下降法求解。计算机仿真表明,与块正交匹配追踪和块压缩采样匹配追踪比较,新算法能够在保持高重构精度的前提下获得更快的计算速度。     

Viewing direction measurements on flat and curved flexible E‐paper displays

The viewing direction characterization of reflective displays is more demanding than for emissive displays because defined illumination–detection geometries must be maintained for each viewing direction. In addition, the geometry should mimic the behavior of viewers who tend to exclude the reflection of light sources from a handheld reflective display. Viewing direction data was extracted from measured Bidirectional Reflectance Distribution Functions, showing that a source inclination of 45° sufficiently excludes the specular and haze components of source reflection from the measurement. Applying this so‐called 45/θ geometry to curved flexible displays is not straightforward since viewing direction, display curvature, and alignment each affect the measured reflectance. The viewing direction geometry proposed for convex cylindrical displays uses a ring light to deliver viewing‐direction independent illuminance, and maps the range of viewing directions onto the pixels of an image sensor. The illumination can also be applied to flat displays, allowing direct comparisons of flat and cylindrical display states. First results on e‐paper show good agreement with Bidirectional Reflectance Distribution Function data.     

质量检测行业在水利工程后期的现状及发展方向

水利工程建设期间成立的各种质量检测机构在工程后期都面临着检测任务减少,投入减少,生存和发展受到严峻的考验。企业走向新的工程或者走向城市建设检测市场是未来各个水利质量检测机构发展的方向。     

S-粗集与数据挖掘单位圆特征

给出单向S-粗集(one direction singular rough sets)、单向S-粗集对偶(dual of one direction singular rough sets)的结构。单向S-粗集与单向S-粗集对偶是改进Z.Pawlak粗集得到的,单向S-粗集与单向S-粗集对偶具有动态特性。给出单向S-粗集、单向S-粗集对偶与Z.Pawlak粗集的关系。S-粗集具有三类形式:单向S-粗集、单向S-粗集对偶、双向S-粗集,利用单向S-粗集、单向S-粗集对偶,给出数据内挖掘、数据外挖掘概念,给出数据内挖掘的外同心圆定理、数据外挖掘的内同心圆定理,并给出其应用。S-粗集是粗集理论与应用研究的新分支。     

一种离焦模糊图像边缘检测新方法

根据离焦模糊图像的特性,提出一种新的离焦模糊图像边缘检测算法,该算法通过定义一个新的边缘检测算子,利用新算子对图像各像素进行卷积,求得各像素的梯度和方向信息,根据梯度和方向信息进行阈值化处理,得到离焦模糊图像的边缘检测图像。实验结果表明,对于离焦模糊图像,利用新的边缘检测算子进行边缘检测,能够较好地检测被模糊而弱化的边缘,检测效果符合人眼视觉感受。     

基于方向ROEWA算子的高分辨率SAR图像道路提取

指数加权均值比率ROEWA算子是SAR图像阶跃边缘提取中较为常用的算法,但该方法只能提取边缘强度,不能得到边缘方向。本文在ROEWA算子的基础上,利用添加方向模板的方法,提出了获取边缘方向的ROEWA改进算法。并根据得到的边缘方向,分别提出了一种边缘筛选算法和快速的Hough变换算法,从而提取出图像中的直线信息。实验表明,本文方法准确、高效,且对SAR图像中的相干斑噪声具有很好的抑制作用。     

A model for describing and composing direction relations between overlapping and contained regions

Current models of direction relations are not designed to describe direction information inside the Minimum Bounding Rectangle (MBR) of a reference region. Thus, the direction relations between overlapping and contained regions cannot be effectively described and derived. To resolve this problem, a new model of direction relations, namely interior-boundary direction relations, is proposed in this study to describe direction concepts relative to the interior or boundary of a region, such as “east part of a region”, “west border of a region”, “a line goes through east part of a region”, and etc. By combining the interior and exterior direction relations, three types of compositions of direction relations are investigated: (1) composing two interior direction relations which can be used to derive the interior or exterior direction relations between two regions with the same parent region; (2) composing an interior direction relation with an exterior direction relation; and (3) composing an interior with an exterior direction relation. The results indicate that the new interior-boundary direction relations and its compositions with exterior direction relations are powerful in describing and deriving direction relations between overlapped and contained regions.     

An ant direction hybrid differential evolution heuristic for the large-scale passive harmonic filters planning problem

This article presents a heuristic which combines the orthogonal array experiment technique and an ant direction hybrid differential evolution algorithm (ADHDEOA) for planning of a large-scale passive harmonic filters problem. The addressed problem has a multi-bus and under abundant harmonic current sources in the system. In this study, an orthogonal array is first conducted to obtain the initial solution. Next, an ant direction hybrid differential evolution (ADHDE) is applied to search for a near optimum solution. The objective is to minimize the cost of the filter, the total demand distortion of harmonic currents and the total harmonic distortion of voltages at each bus simultaneously. In order to determine a set of weights of each term in the objective function, the simplest and most efficient form of triangular membership functions has been considered. The designed heuristic ADHDEOA is applied to a practical harmonic problem in a steel plant, and three design schemes are compared to demonstrate the performance of the ADHDEOA.     

基于单亲遗传算法和导向算子的图像分形编码

基于图像的近距自相似性,用一种采用实数编码的单亲遗传算法完成图像分形压缩中的最优码本匹配,针对含有边缘的Range块的匹配,通过一个导向算子使边缘R块的最优匹配搜索沿着图像的边缘进行。实验结果表明,相对于基本分形压缩算法,在基本保证解码图像主观质量的前提下,该方法的速度提高了约60倍。