Tracking of moving interfaces in sedimentation processes using electrical impedance tomography

Sedimentation monitoring is widely used to control and optimize industrial processes. In this paper we propose a novel computational method for sedimentation monitoring using electrical impedance tomography (EIT). EIT measurements consist of electric current and voltage measurements that are made on the surface of the sedimentation tank and therefore they do not interfere with the sedimentation process. The proposed computational method is based on shape estimation and state estimation formulation of the EIT problem. The sedimentation is parameterized by the locations of the phase interfaces and conductivities of the phase layers. Three different evolution models for the state parameters are considered and the state estimates are computed using the extended Kalman filter algorithm. The performance of the method and the models are evaluated using simulated data from a six electrode EIT measurement configuration. From the results a promising performance of the method can be seen.     

Image edge detection based on multi-fractal spectrum analysis

In this paper, an image edge detection method based on multi-fractal spectrum analysis is presented. The coarse grain H?lder exponent of the image pixels is first computed. then, its multi-fractal spectrum is estimated by the kernel estimation method. Finally, the image edge detection is done by means of different multi-fractal spectrum values. Simulation results show that this method is efficient and has better locality compared with the traditional edge detection methods such as the Sobel method. __________ Translated from Journal of Hunan University (Natural Sciences), 2004, 31(4): 28–33     

DS-SS通信扩频序列的估计

该文给出一种在各通信参数未知的情况下估计出DS-SS通信中伪随机码的方法,并对这一算法进行了仿真及性能分析。     

矿业软件在矿产储量评价中的应用

矿产储量评价的基本内容是建立矿床地质模型进行品位估计和储量分类分级．地质控制条件限制是矿床建模的重要手段。地质统计学方法是矿块品位估计以及储量分级等的有效方法．国内的应用实例表明。国际先进矿业软件是矿产储量评价的先进工具，应用矿业软件进行矿产储量评价是市场经济的需要。     

Improved estimation of defocus blur and spatial shifts in spatial domain: a homotopy-based approach

This paper presents a homotopy-based algorithm for the recovery of depth cues in the spatial domain. The algorithm specifically deals with defocus blur and spatial shifts, that is 2D motion, stereo disparities and/or zooming disparities. These cues are estimated from two images of the same scene acquired by a camera evolving in time and/or space. We show that they can be simultaneously computed by resolving a system of equations using a homotopy method. The proposed algorithm is tested using synthetic and real images. The results confirm that the use of a homotopy method leads to a dense and accurate estimation of depth cues. This approach has been integrated into an application for relief estimation from remotely sensed images.     

Rolling and swaying motion estimation for a mobile robot by using omnidirectional optical flows

Described here is a method for estimating rolling and swaying motions of a mobile robot using optical flow. We have proposed an image sensor with a hyperboloidal mirror for the vision-based navigation of a mobile robot. Its name is HyperOmni Vision. The radial component of optical flow in HyperOmni Vision has a periodic characteristic. The circumferential component of optical flow has a symmetric characteristic. The proposed method makes use of these characteristic to estimate robustly the rolling and swaying motion of the mobile robot. Correspondence to: Y. Yagi e-mail: y-yagi@sys.es.osaka-u.ac.jp     

总体评价法在非线性控制系统极限环振荡研究中的应用

本文简要介绍了总体评价法在研究非线性控制系统极限环振荡方面的理论和应用。文中提供了大量例子说明总体评价法的正确和可信。总体评价法只需用少量的图和表就能方便地掌握系统中各种不同大小的非线性因素处于系统各种不同位置时，对系统动态性能的定性和定量影响，从总体上揭示非线性系统的各种特点。这无疑可以改进系统设计和改善运行性能。     

Application of multi-layer perceptron neural networks to vision problems

This paper discusses the application of a class of feed-forward Artificial Neural Networks (ANNs) known as Multi-Layer Perceptrons(MLPs) to two vision problems: recognition and pose estimation of 3D objects from a single 2D perspective view; and handwritten digit recognition. In both cases, a multi-MLP classification scheme is developed that combines the decisions of several classifiers. These classifiers operate on the same feature set for the 3D recognition problem whereas different feature types are used for the handwritten digit recognition. The backpropagationlearning rule is used to train the MLPs. Application of the MLP architecture to other vision problems is also briefly discussed.     

一种新的半像素快速搜索算法

提出了一种基于在整像素搜索结果的± 1像素邻域内 SAD函数随着与亚像素全局最小点距离的增加而单调增大的半像素两步快速搜索算法。本算法相继在水平和垂直两个共轭的方向上搜索半像素 SAD值的最小点 ,从而得到运动矢量的半像素分量。同时还采用了在每次计算 SAD值之前按需对块进行插值的方法。仿真结果表明本算法在保持图像质量和码流长度基本不变的同时使运算量下降到原来的一半以下。     

快速次优固定区间Wiener平滑器算法

为了克服带相关噪声控制系统的最优固定区间Kalman平滑算法要求较大计算负担的缺点,应用Kalman滤波方法,基于CARMA新息模型,由稳态最优Kalman平滑器导出了带相关噪声控制系统的最优固定区间Wiener递推状态平滑器,它带有系数阵指数衰减到零的高阶多项式矩阵.用截断系数矩阵近似为零的项的方法提出了相应的快速次优固定区间Wiener平滑算法.它显著地减少了计算负担,便于实时应用,还给出了截断误差公式和选择截断指标的公式.仿真例子说明了快速平滑算法的有效性.