Two-parameter Fisher criterion.

This paper proposes further generalization of a multiclass Fisher's criterion. A formula describing the dependence between the generalized multiclass Fisher's criterion F(Theta) and the variance criterion F(v)Theta has been obtained. Using this formula, it has been shown that the feature extraction methods based on the Karhunen-Loeve (K-L) expansions are special cases of the discriminant method. A full evaluation of heuristic methods for feature extraction based on the K-L expansion with regard to discriminant methods has been presented. A new algorithm for sequential feature extraction has been proposed and is illustrated with an example.     

Computer diagnosis of goiters. V. The input

A scheme in which model construction and operation are considered as distinct processes has been designed for the differential diagnosis of goiters. The influence of classification and observation errors and of the recognition method on the diagnostic accuracy has been determined.     

A novel incremental principal component analysis and its application for face recognition.

Principal component analysis (PCA) has been proven to be an efficient method in pattern recognition and image analysis. Recently, PCA has been extensively employed for face-recognition algorithms, such as eigenface and fisherface. The encouraging results have been reported and discussed in the literature. Many PCA-based face-recognition systems have also been developed in the last decade. However, existing PCA-based face-recognition systems are hard to scale up because of the computational cost and memory-requirement burden. To overcome this limitation, an incremental approach is usually adopted. Incremental PCA (IPCA) methods have been studied for many years in the machine-learning community. The major limitation of existing IPCA methods is that there is no guarantee on the approximation error. In view of this limitation, this paper proposes a new IPCA method based on the idea of a singular value decomposition (SVD) updating algorithm, namely an SVD updating-based IPCA (SVDU-IPCA) algorithm. In the proposed SVDU-IPCA algorithm, we have mathematically proved that the approximation error is bounded. A complexity analysis on the proposed method is also presented. Another characteristic of the proposed SVDU-IPCA algorithm is that it can be easily extended to a kernel version. The proposed method has been evaluated using available public databases, namely FERET, AR, and Yale B, and applied to existing face-recognition algorithms. Experimental results show that the difference of the average recognition accuracy between the proposed incremental method and the batch-mode method is less than 1%. This implies that the proposed SVDU-IPCA method gives a close approximation to the batch-mode PCA method.     

Microcomputer programs for complex epidemiologic procedures. I. Computation of adjusted rates

In epidemiological cohort studies one measure of association based directly on incidence or mortality rates is the excess rate. This measure is defined as the excess in these rates between two groups with different exposure experience. At times the computation of these excess rates separately for each of the categories of a risk factor is crucial, as with these rates we can then determine whether the factor exerts a dose-response effect that may implicate a causal relation. Recently an indirect method of standardization has been reported, which computes the excess rates for a factor that are adjusted for the confounding effects of several other factors. The method involves a complex iterative procedure that cannot be carried out easily without the aid of a computer. The objective of this communication is to make available a microcomputer program that has been written to implement this laborious computation. In this pedagogic note the adjustment method is described and the application of the microcomputer program is illustrated.     

Image-based predictive display for high d.o.f. uncalibrated tele-manipulation using affine and intensity subspace models

The addition of immediate but estimated visual feedback, called predictive display, improves tele-manipulaton performance when the real video feedback is delayed. Current systems typically rely upon a previously calibrated camera and manipulator. We present a method where the motor-visual calibration is estimated on-line from motor commands and returned video images only. Predicted visual feedback is presented in two forms. As soon as a basic model has been estimated, a wire frame drawing of the predicted current pose is overlaid on the delayed video feedback. After some time when a rich model has been estimated, predicted intensity images are synthesized and these replace the delayed real video. In an intermediate situation where blurry synthesized images can be computed, the wireframe is overlaid on the synthesized images to show precisely the pose of the object. Experiments with a Utah/MIT robot hand and PUMA robot arm are shown.     

基于小波子图映射的疵点织物判定方法

为了提高织物自动化疵点检测的效率和准确性,提出了一种基于小波子图映射的疵点织物判定方法,并详细阐述了小波子图映射、子图能量统计、子图能量分析,最终判定这一系列操作过程及相关的理论分析。通过实验以及与相关方法的比较,说明该方法的准确性高,可靠性强,计算量低,实现成本小,具有实践意义。     

船舶企业质量控制模型及数据仓库的构建

为有效对船舶企业产品质量进行控制和分析,针对造船企业质量信息特点,提出了基于过程质量数据仓库的多维数据模型,建立了面向主题的船舶企业质量数据仓库。并通过对OLAP数据源中抽取的数据进行转换,构建了面向产品实现全过程的企业主题数据模型,为船舶企业质量管理体系的稳步改进提供了技术保证。通过在某船舶企业的实际应用,验证了该模型和方法的合理性和有效性。     

基于H.263+视频传输的误差恢复技术

论文提出了一种应用于H.263+视频传输的误差恢复方法,即基于H.263+视频编解码器的差错掩盖方法。在这种方法中,在编码器端通过重传出现差错的数据和发送帧内编码帧来限制误差的扩散和繁衍;在解码器端利用视频信号在空间域和时间域上的相关性对受损的数据进行误差掩盖。模拟结果表明,这种误差恢复方法能够使得在有噪音干扰信道上传输的图像质量获得明显改善。其可以应用于公共交换电话网(PSTN)、Internet等能够提供反馈信道的视频通信环境中。     

面向属性的归纳与概念聚类

面向属性的归纳是新近提出的一种广泛用于数据库中的知识发现的方法，提出这种方法与一种机器学习方法－－概念聚类之间的紧密联系，并描述如何使用一个概念聚类算法进行面向属性的归纳。     

Unitary events in multiple single-neuron spiking activity: I. Detection and significance.

It has been proposed that cortical neurons organize dynamically into functional groups (cell assemblies) by the temporal structure of their joint spiking activity. Here, we describe a novel method to detect conspicuous patterns of coincident joint spike activity among simultaneously recorded single neurons. The statistical significance of these unitary events of coincident joint spike activity is evaluated by the joint-surprise. The method is tested and calibrated on the basis of simulated, stationary spike trains of independently firing neurons, into which coincident joint spike events were inserted under controlled conditions. The sensitivity and specificity of the method are investigated for their dependence on physiological parameters (firing rate, coincidence precision, coincidence pattern complexity) and temporal resolution of the analysis. In the companion article in this issue, we describe an extension of the method, designed to deal with nonstationary firing rates.     

面向H.264运动估计的分数搜索方法

H.264在进行运动估计时,为了提高搜索的准确性,在整数搜索得到的最佳点的周围,进行了精确度更高的分数搜索,文章给出了基于H.264的一种新分数搜索算法,可降低搜索点数,提高运动估计搜索的速度,并通过实验进行了验证。     

Determination of the method of construction of 1650 B.C. wall paintings

In this paper, a methodology of general applicability is presented for answering the question if an artist used a number of archetypes to draw a painting or if he drew it freehand. In fact, the contour line parts of the drawn objects that potentially correspond to archetypes are initially spotted. Subsequently, the exact form of these archetypes and their appearance throughout the painting is determined. The method has been applied to celebrated Thera Late Bronze Age wall paintings with full success. It has been demonstrated that the artist or group of artists has used seven geometrical archetypes and seven corresponding well-constructed stencils (four hyperbolae, two ellipses, and one Archimedes' spiral) to draw the wall painting "Gathering of Crocus" in 1650 B.C. This method of drawing seems to be unique in the history of arts and of great importance for archaeology, and the history of mathematics and sciences, as well.     

Kinematic analysis of a translational 3-d.o.f. micro-parallel mechanism using the matrix method

In this paper, we applied the matrix method to kinematic analysis of our translational 3-d.o.f. micro-parallel mechanism for an instance of general flexure mechanisms. The matrix method has been well developed in architecture to analyze frame structures. We found that this method is well suited to such a flexure mechanism with circular notched hinges as our micro-parallel mechanism because it can be approximated to a Rahmen structure. Our matrix method can calculate a compliance matrix with less matrix nodes than the conventional finite element method. First, the compliance matrices of a circular notched hinge and some other beams are defined, and the coordinate transformations of the compliance matrix are introduced. Secondly, an analysis of our micro-parallel mechanism is demonstrated.     

QSAR studies of the pyrethroid insecticides. Part 3. A putative pharmacophore derived using methodology based on molecular dynamics and hierarchical cluster analysis

Previous studies of the conformational behaviour of a group of synthetic pyrethroid insecticides have been extended to a more structurally diverse set. This includes compounds with different backbones and differing stereochemistry, with both Types I and II biological activity. These compounds also encompass a large range of biological activities. A parameterisation of the CHARMM force field for these compounds has been performed and the extra parameters are reported. Conformational sampling, using molecular dynamics (MD), has been performed for each of the 41 active structures. The accessible conformations of each have been characterised by the values of the common torsion angles using hierarchichal cluster analysis (HCA). A further CA, based on the centroids derived from the conformational sampling, identified a conformation common to at least 39 of the 41 structures. The critical torsion angles of this conformation lie at the centre of the molecule about the ester linkage and are defining an extended conformation, which differs from the minimum energy conformation of deltamethrin used previously. This may represent a putative pharmacophore for kill. The methods used here improve significantly on those used previously. The CHARMM force field was parameterised for the compounds and an improved method of conformational sampling, based on centroid clustering, has also been used.     

规则基专家系统概率区间推理模式研究

知识不确定性的二值表示法已经成为专家系统中不确定推理模型设计的重要出发点,本文基于不确定信息的概率区间表示,给出了专家系统中不确定信息的组合、积累和传播过程中概率区间的计算模式,并结合一个实例进行了说明。最后,我们对概率区间计算理论的一般情况进行了讨论。     

Modal synthesis: Generalization of MacNeal's method. theoretical basis

In this paper, a theoretical basis of the generalization of MacNeal's modal synthesis method [1] is presented.This method allows the computation of eigenvectors and eigenfrequencies of a structure from the eigenfrequencies and modes of the subcomponents of this structure, already independently analysed. These frequencies and modes may have been obtained by computation or measured. A set of linear equations expresses the assembly conditions of the subsets.There are in this method no restrictions on the boundary conditions of the subsets. They may have been analysed free-free or supported. The global system may also be supported or not.This theoretical formulation has been introduced and tested in the ASKA program.     

基于Faster-RCNN的结核杆菌自动检测方法研究与应用

染色处理可使结核杆菌在显微镜拍摄的医学图像中显现,医生通过检测图像中的 结核杆菌辅助诊断结核病。近年来卷积神经网络(CNN)在目标检测上取得了突破性进展,但结 核杆菌存在图像上尺度小,构造标注数据难,不适用迁移学习等问题,使得基于 CNN 的目标 检测方法在结核杆菌检测方面尚存在一定的困难。为此,以 Faster-RCNN 目标检测算法为基 础,研究在医学图像上的结核杆菌检测问题。针对结核杆菌尺度小,提出重叠子图划分策略; 针对标注数据构造难,提出分块、迭代标注策略。实践证明,该方法有较高的准确度以及可 接受的速度,已构建了 13 261 个结核杆菌的训练数据,应用于合作单位的医疗检测产品,能 满足实际应用需求。     

Numerical analysis of coupled thermomechanical frictional contact problems. Computational model and applications

Summary In this paper a numerical model for the analysis of coupled thermomechanical multi-body frictional contact problems at finite deformations is presented. The multi-body frictional contact formulation is fully developed on the continuum setting and then a spatial (Galerkin projection) and temporal (time-stepping algorithm) discretization is applied. A contact pressure and temperature dependent thermal contact model has been used. A fractional step method arising from an operator split of the governing equations has been used to solve the coupled nonlinear system of equations, leading to a staggered solution algorithm. The numerical model has been implemented into an enhanced version of the computational finite element program FEAP. Numerical examples and simulation of industrial metal forming processes show the performance of the numerical model in the analysis of coupled thermomechanical frictional contact problems.     

Integrating human factors with the Jackson System Development method: an illustrated overview.

The motivation for integrating human factors with structured systems analysis and design methods has been set out in earlier papers. In addition, a preliminary conception of such an integration has been proposed for the Jackson System Development method (referred to as JSD*), and a set of requirements, research and strategies suggested for further developing this conception. The present paper reports the progress of the research, and presents an overview of the stage-wise design process, scope and notation of the JSD* method. The method is discussed and illustrated using a simple case-study concerning a Recreation Booking System.