Equilibria and their bifurcations in a recurrent neural network involving iterates of a transcendental function.

Some practical models contain so complicated mathematical expressions that it is hard to determine the number and distribution of all equilibria, not mentioning the qualitative properties and bifurcations of those equilibria. The three-node recurrent neural network system with two free weight parameters, originally introduced by Ruiz, Owens, and Townley in 1997, is such a system, for which the equation of equilibria involves transcendental function tanh(x) and its iterates. Not computing coordinates of its equilibria, in this paper, we display an effective technique to determine the number and distribution of its equilibria. Without full information about equilibria, our method enables to further study qualitative properties of those equilibria and discuss their saddle node, pitchfork, and Hopf bifurcations by approximating center manifolds.     

The CAS-PEAL Large-Scale Chinese Face Database and Baseline Evaluations

In this paper, we describe the acquisition and contents of a large-scale Chinese face database: the CAS-PEAL face database. The goals of creating the CAS-PEAL face database include the following: 1) providing the worldwide researchers of face recognition with different sources of variations, particularly pose, expression, accessories, and lighting (PEAL), and exhaustive ground-truth information in one uniform database; 2) advancing the state-of-the-art face recognition technologies aiming at practical applications by using off-the-shelf imaging equipment and by designing normal face variations in the database; and 3) providing a large-scale face database of Mongolian. Currently, the CAS-PEAL face database contains 99 594 images of 1040 individuals (595 males and 445 females). A total of nine cameras are mounted horizontally on an arc arm to simultaneously capture images across different poses. Each subject is asked to look straight ahead, up, and down to obtain 27 images in three shots. Five facial expressions, six accessories, and 15 lighting changes are also included in the database. A selected subset of the database (CAS-PEAL-R1, containing 30 863 images of the 1040 subjects) is available to other researchers now. We discuss the evaluation protocol based on the CAS-PEAL-R1 database and present the performance of four algorithms as a baseline to do the following: 1) elementarily assess the difficulty of the database for face recognition algorithms; 2) preference evaluation results for researchers using the database; and 3) identify the strengths and weaknesses of the commonly used algorithms.     

Low-complexity and energy efficient image compression scheme for wireless sensor networks

Currently most energy-constrained wireless sensor networks are designed with the object of minimizing the communication power at the cost of more computation. To achieve high compression efficiency, the main image compression algorithms used in wireless sensor networks are the high-complexity, state-of-the-art image compression standards, such as JPEG2000. These algorithms require complex hardware and make the energy consumption for computation comparable to communication energy dissipation. To reduce the hardware cost and the energy consumption of the sensor network, a low-complexity and energy efficient image compression scheme is proposed. The compression algorithm in the proposed scheme greatly lowers the computational complexity and reduces the required memory, while it still achieves required PSNR. The proposed implementation scheme of the image compression algorithm overcomes the computation and energy limitation of individual nodes by sharing the processing of tasks. And, it applies transmission range adjustment to save communication energy dissipation. Performance of the proposed scheme is investigated with respect to image quality and energy consumption. Simulation results show that it greatly prolongs the lifetime of the network under a specific image quality requirement.     

Research on immune algorithm for mobile phone viruses detection

In responds to the problem that mobile phone viruses is much more serious but the detection technology for them is not maturity, there is a new way for mobile phone viruses detection. Which is based on the viruses＇ work principle and infection ways, introduced immune algorithm into computer viruses defense detection and set up mobile phone viruses detection model based on minus select immune algorithm. At the same time, it also made analysis on immune algorithm viruses detection and found an approach to probing to mobile phone viruses.     

A corner differentiation algorithm by a single sonar sensor for mobile robots

Ultrasonic sensors have been widely applied in mobile robots to obtain environmental information and avoid obstacles. In general, a typical domestic environment consists of planes, edges and corners. It is usually difficult to distinguish a plane from a corner directly with a single ultrasonic sensor. To overcome this difficulty, a corner differentiation algorithm for a single ultrasonic sensor is proposed in this paper. The algorithm is based on the features of all of the actual reflection points from the environment obtained by a reflection search algorithm from which the corners are realized by a corner differentiation algorithm. The experimental results show that the developed algorithm can successfully detect all planes and corners. Furthermore, an environmental map can be built based on the information obtained on planes and corners. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

不平衡输入改进双电压合成策略的研究

为了改善电压不平衡时矩阵变换器的输入、输出性能,文章提出了一种改进的双电压合成策略,介绍了一种新的指令电流计算公式,即通过三相输入电压直接计算正、负序电压以产生指令电流。仿真实验验证了不平衡条件下双电压合成控制策略改进研究的正确性。     

一种新的商务手机结构方式设计

本设计结合TCL的设计理念,通过对概念的局部创新赋予手机产品突出的亮点,使用科技美学化的设计语言赋予产品夺目的外观,达到形式与外观的统一。满足商务人士对手机产品功能、结构、外观等方面的要求。在克服现有的双向开合手机转轴占用机身空间、结构不够坚固、操作模式单一等不足,特提出通过主轴旋转实现手机双向开合的结构设计。     

基于Smart Client的军队网上考评系统的改进

随着军队网上训练与考评系统在部队各单位的广泛使用,传统的C/S或B/S模型的军队网上训练与考评系统不能满足实际应用的需求,利用新技术对原系统进行改进成为亟需解决的问题.讨论了目前比较先进的Smart Ciient技术,并利用该技术对原有的军队网上训练与考评系统进行设计与改进,介绍了系统的结构、改进的关键部份的实现.该系统已经成功地应用于兰州军区各单位,并取得了很好的效果.     

基于语义关键词的本体特征指数获取方法研究

本体作为知识表达的范例工具,依赖于语义来进行逻辑推理.但在本体搜索时依赖于语义进行搜索十分困难.针对当前本体搜索中存在的问题,提出了一种通过拆分概念来获取语义关键词进而通过计算权值来获得一组本体特征指数的方法.详细阐述了如何获取本体的一组特征指数,即能够描述本体的一组相关的关键词.通过该方法所提炼的语义关键词对于本题搜索以及本体构建工作具有指导意义.     

融合粒子群算法改进XML数据智能清洗策略

针对XML数据质量问题,以XML键为基础、借助多模板隐马尔可夫模型信息抽取策略与粒子群算法构建新的XML数据清洗方法;为了提高XML相似性数据并行检测效率,尝试利用波函数对粒子群算法进行相应优化．对比其他XML数据清洗算法,一系列仿真实验表明改进的XML数据清洗方法不仅自适应学习功能强、人工参与程度低、计算量小,而且时间性能有94％左右提升．