纹理相似性度量研究及基于纹理特征的图像检索

纹理相似性研究是纹理合成和基于内容检索研究中的一个重要组成部分.在相似性 判断中,采用与人类视觉感知相对应的纹理特征,将比使用其他无明确含义的纹理特征,对 系统的进一步改善有着更为重要的指导意义.在Tamura,Amadasun和Haralick等人提出的 纹理特征的基础上分析了与人类视觉特征有较为明确对应关系的19个纹理特征,不同纹理 之间的相似性由这19个纹理特征构成的归一化特征向量之间的加权欧氏距离决定.对大量 纹理图像的相似性进行了度量,实验结果表明所选的纹理特征有较强的描述能力.使用了主 成分分析算法来压缩特征向量的维数,结果表明,6维特征主分量已经可以给出较好的纹理相 似性度量.     

生物多样性和均匀度显著性的统计检验及网络计算软件

Shaanon-Wiener多样性指数和均匀度以其简单易用而被广泛应用于生物多样性和群落生态学等研究中。然而，由于缺乏适合的统计检验等原因，其分析的可信性较低，本研究以Shaanon-Wiener指数和Ewens-Caswell检验为基础，研制了生物多样性和均匀度显著性统计检验的Internet计算软件EwensCaswellTest。该软件由4个Java类和一个HTML文件组成，可运行于多种网络浏览器上。用EwensCaswellTest对水稻田节肢动物群落多样性（15个地点，17个功能群），以及中国民族HLA-DQB1等位基因的多态性（12个民族和人群，17个等位基因）进行了分析。结果显示，该检验可有效地反映多样性和均匀度的显著性。     

基于GO体系的基因功能相似性度量方法

比较基因或基因产物功能上的相似性是生命科学研究的一项重要内容,它在生物大分子功能预测、基因聚类、生物网络分析和疾病相关基因筛选等方面具有广泛的应用。计算基因之间的功能相似性已经成为生物信息学研究的基础性工作。基因本体GO(Gene Ontology)体系集成了多种异质数据库的信息,用结构化的自然语言术语对基因和基因产物的功能进行注释和分类,是研究基因功能相似性的有力工具。从GO术语之间相似性、基因之间功能相似性两个方面,总结和评述过去十几年里,人类利用生物信息学方法在语义水平上研究基因功能相似性的进展和取得的成果,分析基因功能相似性计算方法存在的问题和面临的挑战,指出基于GO体系的基因功能相似性度量方法今后的主要研究方向。     

序列数据相似性查询技术研究综述

序列数据在文本、Web访问日志文件、生物数据库等应用中普遍存在,对其进行相似性查询是一种提取有用信息的重要手段.近年来,随着各种科学计算的发展和序列数据的大量产生,序列相似性查询已经成为数据分析领域一个研究热点.其涉及到的几个重要问题有面向各种应用领域的相似性度量及其相互之间的关系;随机序列数据中距离分布的统计信息及其对分析查询算法性能的作用;在大规模数据中,各种高效回答相似性查询的关键技术及各自的优缺点比较.总结了序列数据的分类和特点,给出了几种序列数据相似性度量和随机序列之间距离分布的统计信息,并进一步分析了这些度量之间的关系.接着给出了几种序列相似性查询的类型,以及序列相似性查询要解决的核心问题.在此基础上,针对各种序列相似性查询关键技术进行分类和评价.最后,讨论了关于序列数据相似性查询研究所面临的挑战,并归结了未来的研究方向.     

基于相似性的图像融合质量的客观评估方法

研究图像融合结果的质量评估问题,提出一种新的基于相似性的图像融合质量客观评估方法.这种方法考虑人类视觉对局部变化更加敏感的特性,用源图像和融合结果的梯度场相似性来衡量融合的性能.这种相似性度量相对于现有的对比度度量,有了全方向的边缘辨识能力;相对于互信息量的度量方法,考虑了图像像素的局部关系,更加符合人的视觉特征.实验结果表明,这种客观评估方法很好地反映了图像融合的质量,与主观评价具有高度的一致性.     

Road2vec:一种基于出租车轨迹数据的城市道路可视分析方法EI北大核心CSCD

发掘轨迹数据的时空连续性对分析路网结构和人类移动模式的非常重要,基于出租车GPS数据,提出一种城市道路的可视分析方法——road2vec.首先利用词嵌入技术将轨迹数据视为文本进行建模,得到道路的向量表示形式;然后计算得到道路向量在向量空间中的位置关系,并用这种位置关系来表示道路向量之间的相似性;最后根据相似性来探索道路在轨迹中的位置信息和连接关系.文中还设计了一套可视分析系统,以支持用road2vec方法探索城市道路相关信息.基于温州市出租车GPS数据的案例分析表明,该方法可以有效地反映人群在城市路网中的移动模式.     

GCT变换及几何图形形状相似性判定

目的 人类的视觉能力可以轻易地判定两个几何图形形状的相似性,但是,这对于计算机来说仍是一个开问题。在计算机视觉应用中,不仅需要对图形形状进行分类和相似性判定,还需要对图形形状的相似性度量给出与人类的视觉判断一致的结果,这是目前图形形状表示和分类算法没有较好解决的问题。方法 通过GCT变换,将图形形状从实数空间的坐标表示变换到复数空间的复数特征向量表示,进而将判定两个几何形状的相似性问题转化为判定它们的复数空间特征向量的相似性问题。GCT变换不仅可以判定图形形状的相似性,它还是可逆的,它可以近似重建原图形形状。结果 GCT变换具有位移、尺度和旋转不变性,它不仅可以判定几何图形形状的相似性,给出与人类视觉判断一致的相似性结果,而且在两个几何图形形状相似的情况下,还能计算出它们的角度旋转和尺度缩放。结论 对于封闭的几何形状,如果几何形状的中心点位于几何形状的内部且过中心点的任一直线与该几何形状有且只有两个交点,理论证明和实验验证,GCT变换可以高效准确地判定这类几何图形形状的相似性,并给出与人类视觉判定一致的结果。     

基于等价分量交叉相似性的Pareto支配性预测

研究用最近邻分类预测多目标优化问题Pareto支配性的相似性测度方法. 在分析决策分量对各目标分量贡献率的基础上定义决策向量的等价子向量,等价子向量由贡献率相同的决策分量所组成.提出基于等价子向量的最小交叉距离加 权和相似性测度方法.对每个目标分量,独立评价待测数据与N个已知样本的相似度,每个样本按其相似度值的升序赋予[0:N-1]之间的序号,按各目标上的序号之和最小准则确定最近邻样本.等价子向量最小交叉距离加权和相似性测度以及多目标最近邻搜索方法在确定决策向量相似性时,引入了决策空间到目标向量空间的映射知识,使决策变量相似性测度更真实地反映目标向量相似性.对典型多目标优化问题的Pareto支配性最近邻分类实验结果表明,提出的方法可显著地提高分类准确性.     

非血统文化圈的汉民族族称问题试探

羌族人夏启建立了中国历史上第一个真正意义上的国家夏朝。夏王朝的主要部族是羌;西汉元始年羌族总人口多达1300多万,占全国总人口的四分之—,是当时的主体民族。汉族是以羌人为主体发展和壮大而来。羌族在现代中国人染色体里Y占有最大比重。汉族之名起于刘邦称帝之后。汉民族本来就不是血统圈,而是文化圈。     

基于平均交互信息量的DNA序列相似性分析

序列相似性分析是生物信息学中一个重要问题,对于研究物种的进化起源有着重要的意义.序列相似性算法包括基于序列比对的方法及非比对方法两种.基于比对的方法对于序列整体的衡量略有欠缺;非比对算法中有DNA曲线化方法以及比较序列各自整体碱基分布间的信息量差异的方法,只是考虑了序列整体信息间的差异,但未考虑序列各个位点间的差异.因此,提出了一种基于信息熵的相似性度量模型,把序列比对与信息量差异结合起来,将两条比对后的序列间的平均交互信息量与其联合熵之比作为两条序列的相似性度量.使用该度量构建了11个物种的相似性矩阵,对各物种间的相似性进行了分析,结果在一定程度上与生物分类学相契合.通过距离矩阵所构建的进化树,也反映了各物种间的进化关系,表明该模型的设计具有合理性.     

Human performance interfaces in air traffic control

This paper examines how human performance factors in air traffic control (ATC) affect each other through their mutual interactions. The paper extends the conceptual SHEL model of ergonomics to describe the ATC system as human performance interfaces in which the air traffic controllers interact with other human performance factors including other controllers, software, hardware, environment, and organisation. New research hypotheses about the relationships between human performance interfaces of the system are developed and tested on data collected from air traffic controllers, using structural equation modelling. The research result suggests that organisation influences play a more significant role than individual differences or peer influences on how the controllers interact with the software, hardware, and environment of the ATC system. There are mutual influences between the controller-software, controller-hardware, controller-environment, and controller-organisation interfaces of the ATC system, with the exception of the controller-controller interface. Research findings of this study provide practical insights in managing human performance interfaces of the ATC system in the face of internal or external change, particularly in understanding its possible consequences in relation to the interactions between human performance factors.     

Correspondence analysis approach for finding allele associations in population genetic study

In population genetic study, one of the first analyses is to explore the relationships among the frequencies of alleles within or between loci. Hardy-Weinberg equilibrium is tested for two alleles of a single locus, and the linkage disequilibrium is tested for an allele from each of two loci. Although the equilibrium plays an important role and often serves as a basis for genetic inference, research on the graphical representation of this information is rare. In this study, we consider correspondence analysis and biplot approaches as tools for finding associations between alleles. We also propose the supplementary data method to compare allele frequencies of several populations from different studies. These approaches provide the graphical representation which makes it easy to interpret the patterns of disequilibrium and to compare the allele frequencies between populations. These proposed methods are illustrated with numerical examples.     

基于国标人体测量学数据的虚拟人缩放方法

具有准确人体测量学数据的虚拟人模型在虚拟制造和虚拟维修领域有重要的理论和现实意义。此外,根据某些人体测量学数据,参照典型的人体模型生成特定的虚拟人,即实现人体模型的参数化控制,对于合理地进行人机功效分析也有重要的应用价值。该文在分析我国成年人体测量学数据标准的基础上,通过研究Jack软件中人体模型表示方法和人体测量学数据之间的映射关系,提出了一种基于人体测量学数据的人体模型动态缩放方法。利用该方法在Jack软件中建立了基于国标人体测量学数据的人体模型动态缩放子系统。     

Tuning lock-based multicore program based on sliding windows to tolerate data race

The Journal of Supercomputing - Because in-house debugging and test are difficult to discover all potential data races in multicore programs, it is necessary and significant to tolerate the...     

基于优化的DTW算法的人体运动数据检索

随着大量三维人体运动数据库的建立,使得在数据库中实现基于内容的三维人体运动检索面临着诸多困难,文中提出一种分阶段的动态时间变形(DTW)优化算法的人体运动数据检索技术,可有效检索出逻辑上相似的运动。该算法首先对齐两个运动序列的坐标位置,基于窗口距离构造距离矩阵。其次采用基于全局和局部约束的DTW优化算法进行相似度匹配,得到两个运动间的对应关系。最后通过归一化相似度和DTW平均距离分阶段判断运动的相似性。实验结果表明,分阶段的DTW优化算法在提高效率的同时对长度不等的运动能取得较好的检索结果。     

An Experimental Study on Three General Interface Layout Designs for Chemical Process Plants

The human‐machine interface design is not a new problem; however, existing knowledge appears to be focused either on interface conceptual design, which determines what information at what time needs to be displayed, or on interface detailed design, which determines the form of display elements. This article presents a study on interface layout design. Three interface layout designs were proposed based on the proximity compatibility priniciple, which were on the same interface conceptual design. In particular, the first interface layout design is with the highest degree of proximity cognition and the second and third with a reduced degree of proximity cognition. They are called sophisticated, semisophisticated, and nonsophisticated interfaces, respectively. An experiment with a simple process plant was conducted to understand user behaviors on the three interfaces. It is noted that in order to provide an unbiased comparative evaluation of these interfaces the same application problem and similar look‐and‐feel forms of interfaces were designed. In the experiment, three general classes of tasks were considered, namely, normal control operation, fault detection (or monitoring), and fault diagnosis. Two categories of measures were used: the performance measure and the subjective measure. The major results obtained from the experiment are 1) the nonsophisticated interface is the best for fault detections in terms of performance measure; besides, this interface has the lowest mental workload for fault detection; 2) the sophisticated interface is the best for normal operation in terms of performance measure; 3) there appears no significant difference for fault diagnosis in terms of performance measures for all these three interfaces; 4) for normal operation and fault diagnosis, the mental workloads for the three interfaces have no significant difference. Overall, the experiment suggests that the nonsophisticated interface be used in practice with additional two reasons: 1) most of time in the chemical process plant today is the fault detection or operation monitoring task, and 2) it is relatively easier for the nonsophisticated interface to adapt to changes in the chemical process plant design, which are common in today's manufacturing environments.     

Using differential solubilization and 2-D gel electrophoresis to visualize increased numbers of proteins in the human cortex and caudate nucleus and putamen

The aim of this study was to determine if differential solubilization of human CNS proteins would increase the total number of proteins that could be visualized using 2-D gel electrophoresis. Hence, proteins were solubilized into Tris, CHAPS and SB3-10 before separation across a pH 4-7 IEF gradient and a 12-14% SDS polyacrylamide gel, which could be achieved with a run-to-run variation of 35% in spot intensity. Because Western blot analyses suggested proteins could be in more than one detergent fraction, we completed a conservative analyses of our 2-D gels assuming spots that appeared on multiple gels at the same molecular weight and pI were the same protein. These analyses show that we had visualized over 3000 unique protein spots across three 2-D gels generated from each sample of human frontal cortex and caudate-putamen. This represented, at worst, a significant increase in the number of spots visualized in the acidic protein spectrum compared to what has been reported in other studies of human CNS. This study, therefore, supports the proposal that the analysis of the human CNS proteome using 2-D gel electrophoresis, combined with appropriate sample preparation, can be used to expand the studies on the pathologies of neurological and psychiatric diseases.     

Estimating sub-pixel components of a semi-arid woodland

Mixture models were applied to Landsat-MSS and -TM data in a semi-arid woodland in central western New South Wales, Australia to extract information on soil, herbage and tree cover. There was a significant correlation (r² = 0-71) between estimated and ground data for tree cover using the TM data, with a mean error of ± 143 per cent, and a mean error of ±11-2 per cent for the bare soil cover estimates. Only general trends were observed using the MSS data. The main areas of confusion were between senesced herbage and soil, and between green grass and the green leaves of trees.