A new method for evaluating the log-likelihood gradient (score) oflinear dynamic systems

A novel method is presented that is based on the optimal smoothing equations. The result can be used for efficient calculations and approximations of gradient-search algorithms for maximum-likelihood estimation of the unknown system parameters. The method is applied to the continuous-discrete case     

A new method for improvement of image quality in medical ultrasonic diagnostics

The problem of dividing noise and texture elements with regard to specific features of an ultrasonic image is studied. A mathematical model is developed that describes statistical and spectral properties of various elements of the image structure. Based on the mathematical model, the procedure of noise suppression is realized. Clinical tests of the method proved its effectiveness.     

A simple and practical method for evaluating machine translation quality

This article describes a simple and cost effective evaluation method based on post-editing. The results of an experiment using this method, to investigate the improvement of an MT system over time are given, along with some practicalities in carrying through the evaluation (time, effort etc.)     

A new discriminative coding method for image classification

Multimedia Systems - The bag-of-words (BOW) based methods are widely used in image classification. However, huge number of visual information is omitted inevitably in the quantization step of the...     

A new benchmark image test suite for evaluating colour texture classification schemes

Several image test suites are available in the literature to evaluate the performance of classification schemes. In the framework of colour texture classification, OuTex-TC-00013 (OuTex) and Contrib-TC-00006 (VisTex) are often used. These colour texture image sets have allowed the accuracies reached by many classification schemes to be compared. However, by analysing the classification results obtained with these two sets of colour texture images, we have noticed that the use of colour histogram yields a higher rate of well-classified images compared to colour texture features. It does not take into account any texture information in the image, this incoherence leads us to question the relevance of these two benchmark colour texture sets for measuring the performances of colour texture classification algorithms. Indeed, the partitioning used to build these two sets consists of extracting training and validating sub-images of an original image. We show that such partitioning leads to biased classification results when it is combined with a classifier such as the nearest neighbour. In this paper a new relevant image test suite is proposed for evaluating colour texture classification schemes. The training and the validating sub-images come from different original images in order to ensure that the correlation of the colour texture images is minimized.     

手指静脉图像质量评价

根据手指静脉图像本身的特征,首次提出了手指静脉图像质量评价方法.在分析人类视觉系统(HVS)性能的基础上,将图像有效区域、对比度、位置偏移度、模糊度、信息熵作为评价手指静脉图像质量的参数.并综合分析这些参数,加权获得静脉图像总质量评价函数.实验表明,得到了与主观评价结果相一致的客观评价值.     

一种角膜新生血管图像的分割方法

为了提高眼科外眼病图像的分割效果,提出了一种基于直方图和形态学的分割方法,用于分割角膜新生血管的充血区域和血管像素,分割结果用于定量分析充血面积和充血密度,并给出实验结果和误差讨论。实验结果表明,该方法简单快速,分割效果较好。     

A new method of fictitious viscous damping determination for the dynamic relaxation method

This paper develops a new method for calculating the viscous fictitious damping of the dynamic relaxation (DR) method to overcome one of the most crucial difficulties in its application – the low convergence rate. The DR formulation was derived by error minimizations between two successive iterations to deduce an optimum fictitious mass and viscous damping with the aid of the Stodola iterative process. The efficiency of the new method was verified by its application to a wide range of typical structures with strong nonlinearity. The results show that compared to the conventional DR algorithm such as kinetic approach, the new method improves the convergence rate considerably.     

A repartition method improving visual quality for PCA image coding

Image coding using principal component analysis (PCA), a type of image compression technique, projects image blocks to a subspace that can preserve most of the original information. However, the blocks in the image exhibit various inhomogeneous properties, such as smooth region, texture, and edge, which give rise to difficulties in PCA image coding. This paper proposes a repartition clustering method to partition the data into groups, such that individuals of the same group are homogeneous, and vice versa. The PCA method is applied separately for each group. In the clustering method, the genetic algorithm acts as a framework consisting of three phases, including the proposed repartition clustering. Based on this mechanism, the proposed method can effectively increase image quality and provide an enhanced visual effect.     

A local structural information representation method for image quality assessment

Multimedia Tools and Applications - Image is a typical example of visual data, and its quality inevitably affects its application. Hence, measuring image quality accurately is a beneficial task. In...     

一种新的星图中星的提取方法

在分析扫描法和矢量法的基础上,提出了块扫描法.首先,根据星像扩散范围和导航星间距确定扫描块的大小;其次,以扫描块为单位,获得其最大灰度值像素,若灰度大于设定背景阈值,则存储其位置信息与灰度值;再次,以存储像素为中心搜索3×3像素阵,若存在像素灰度值大于存储像素,则剔除存储像素;否则,判断像素阵中灰度大于背景阈值的像素个...     

A new level set method for inhomogeneous image segmentation

Intensity inhomogeneity often appears in medical images, such as X-ray tomography and magnetic resonance (MR) images, due to technical limitations or artifacts introduced by the object being imaged. It is difficult to segment such images by traditional level set based segmentation models. In this paper, we propose a new level set method integrating local and global intensity information adaptively to segment inhomogeneous images. The local image information is associated with the intensity difference between the average of local intensity distribution and the original image, which can significantly increase the contrast between foreground and background. Thus, the images with intensity inhomogeneity can be efficiently segmented. What is more, to avoid the re-initialization of the level set function and shorten the computational time, a simple and fast level set evolution formulation is used in the numerical implementation. Experimental results on synthetic images as well as real medical images are shown in the paper to demonstrate the efficiency and robustness of the proposed method.     

A new fast reversible method for image safe transfer

In this paper a novel reversible method for fast and safe image transfer is proposed. The method combines compression, data hiding and partial encryption of images in a single processing step. The proposed approach can embed data into the image according to the message size and partially encrypt the image and the message without changing the original image content. Moreover, during the same process the image is lossless compressed. Nevertheless, the compression rate depends on the upper bound of message size to embed in the image. The main idea is to decompose the original image into two sub-images and to apply various processes to each sub-image in order to gain space and increase the amount of embedded data. The two sub-images are then scrambled and partially encrypted. The most significant characteristic of the proposed method is the utilization of a single procedure to simultaneously perform the compression, the reversible data hiding and the partial encryption rather than using three separate procedures. Our approach reduces then the computational effort and the required computation time. This method is specially suited for medical images where one can associate the patient diagnostic to the concerned medical image for safe transfer purpose.     

A new method for evaluating weapon systems using fuzzy set theory

This paper presents a new method for evaluating weapon systems using fuzzy set theory. The proposed method is more flexible than the one presented in Mon et al. (1994) due to the fact that it allows each item of criteria to have a different weight represented by a triangular fuzzy number. Furthermore, because the proposed method does not need to perform complicated entropy weight calculations, its execution is much faster than the one shown in the above paper     

A new dynamic hydrogen reference electrode for applications in thin-film sensor systems

The realization and applicability of a new dynamic hydrogen reference electrode (DHRE) within an electrochemical microcell for sensor applications is reported. The electrodes are fabricated in thin-film technology and fixed within a flow-through device. An experimental setup for accurate electrochemical potential measurements is described. Smooth platinum, platinized platinum and pHEMA coated electrodes are investigated with regard to their initialization behavior, stability, reproducibility and interference with electrolytes. It is found that platinized platinum DHREs show excellent stability and reproducibility. For uncoated electrodes, the electrochemical potential is established within seconds. The potential is independent of the pH value within the range of pH 4–10. Interference with sulfate and phosphate is observed. Thus, the platinized platinum DHRE is well suited for bioanalytical sensor applications, where the pH value is buffered and the concentrations of the disturbing anions are constant or very low.     

SAHAYOG: A test bed for evaluating dynamic load-sharing policies

This paper describes the implementation of a test bed called SAHAYOG, for evaluating dynamic load-sharing policies in which job-transfer decisions are based on the state of the system. The test bed is implemented on a network of AT&T 3B2 minicomputers. It provides an interactive user interface for conducting load-sharing experiments. Based on user-specified parameters it creates independent job streams at different nodes in the network. Jobs are transferred among the nodes by the load-sharing algorithm being evaluated. Each node collects data about the jobs, which are used to generate statistics about the experiment. Five load-sharing algorithms are implemented and evaluated using the test bed under different load conditions and for various parameter values. These experiments confirm some earlier results about load sharing and also provide some new insights. SAHAYOG also contains an optional fault-tolerance feature to handle single-node failures, and evaluates the effect of fault tolerance on the performance of different policies.     

A new image co-segmentation method using saliency detection for surveillance image of coal miners

In this paper, we propose a co-segmentation method using saliency detection. The input image is first over-segmented into super-pixels, in which, their similarities are measured by the Bhattacharyya coefficients. The proposed method uses the combination of detection results of different detection methods on different types of color space to produce the originating regions, in which optimized linear coefficient combination is exploited. Experiments are performed on different image databases and results comparable to that of some current state-of-the-art methods are provided.     

A new steganographic method for color and grayscale image hiding

In this paper, we present a steganographic method for embedding a color or a grayscale image in a true color image. Three types of secret images can be carried by the proposed method: hiding a color secret image, hiding a palette-based 256-color secret image, and hiding a grayscale image in a true color image. Secret data are protected by the conventional crypto system DES. We compare the image quality and hiding capacity of the proposed method with those of the scheme in Lin et al.’s scheme. According to the experimental results, the image quality of the proposed method is better than that of the Lin et al.’s scheme. In addition, annotation data can be hidden with the secret image in the host image. The hiding capacity of the proposed method is greater than that of other compared schemes. The experimental results show that the proposed method is a secure steganographic method that provides high hiding capacity and good image quality.