state estimation with fading measurements,randomly varying nonlinearities and probabilistic distributed delays

In this paper, the state estimation problem is investigated for a class of discrete‐time stochastic systems in simultaneous presence of three network‐induced phenomena, namely, fading measurements, randomly varying nonlinearities and probabilistic distributed delays. The channel fading is characterized by the ?th‐order Rice fading model whose coefficients are mutually independent random variables with given probability density functions. Two sequences of random variables obeying the Bernoulli distribution are utilized to govern the randomly varying nonlinearities and probabilistic distributed delays. The purpose of the problem addressed is to design an state estimator such that the dynamics of the estimation errors is stochastically stable and the prespecified disturbance rejection attenuation level is guaranteed. Through intensive stochastic analysis, sufficient conditions are established under which the addressed state estimation problem is recast as a convex optimization one that can be solved via the semi‐definite program method. Finally, a simulation example is provided to show the usefulness of the proposed state estimation scheme. Copyright © 2014 John Wiley & Sons, Ltd.     

Petri net based test case generation for evolved specification

Model-based testing can use a model to test a concrete program’s implementation. When the model is changed due to the evolution of the specification, it is important to maintain the test suites up to date, such that it can be used for regression testing. A complete regeneration of the whole test suite from the new model, although inefficient, is still frequently used in practice. To address this problem effectively, we propose a test case reusability analysis technique to identify reusable test cases of the original test suite based on graph analysis, such that we can generate new test cases to cover only the change-related parts of the new model. The Market Information System (MIS) is employed to demonstrate the feasibility and effectiveness of the proposed method. Our experimental results show that the use of our method saves about 31.5% test case generation cost.     

软硬件协同的安全录入系统开发

键盘录入信息的保护大多采用安全软件的方式,无法防止按键信息在录入至计算机途中被硬件记录器非法窃取,且硬件记录器无法被安全软件查杀。本文结合USB驱动技术设计一种可加密防侧录的USB键盘录入系统,通过可加密的USB键盘配合计算机端USB驱动解密的方式,提高按键信息的安全性。测试结果表明,该系统可有效保护按键信息在传输过程中的安全。     

基于X86平台的简单多任务内核的分析与实现

描述了一个简单多任务内核的设计和实现方法。分析了该简单内核的基本结构和加载运行的基本原理,然后描述了其被加载进机器RAM中以及两个任务进行切换的运行方法。     

Effect of Ce(3+) on soluble microbial products production in anaerobic granular sludge digestion

Upflow anaerobic sludge bed reactors fed on glucose were used to investigate the effects of Ce(3+) on soluble microbial products (SMP) production, which is the majority of the residual chemical oxygen demand present in the effluent. It was found that Ce(3+) concentration of 0.05 mg/L had no significant effect on the amount of SMP production, whereas that of 1 mg/L led to the increase in SMP production. The molecular-weight distribution and carbohydrate analysis indicated that an increase in SMP production may be partly attributed to the release of extracellular polymeric substances (EPS) into the bulk solution resulted from cerium toxicity, and the nucleic acids analysis suggested that increased cell lysis also contributed to SMP accumulation in the presence of Ce(3+). The increase in SMP production in the presence of Ce(3+) is possibly a consequence of the release of EPS and increased cell lysis due to cerium toxicity.     

Bounded Consensus Algorithms for Multi‐Agent Systems in Directed Networks

In this paper, the consensus problem is investigated via bounded controls for the multi‐agent systems with or without communication. Based on the nested saturation method, the saturated control laws are designed to solve the consensus problem. Under the designed saturated control laws, the transient performance of the closed‐loop system can be improved by tuning the saturation level. First of all, asymptotical consensus algorithms with bounded control inputs are proposed for the multi‐agent systems with or without communication delays. Under these consensus algorithms, the states’ consensus can be achieved asymptotically. Then, based on a kind of novel nonlinear saturation functions, bounded finite‐time consensus algorithms are further developed. It is shown that the states’ consensus can be achieved in finite time. Finally, two examples are given to verify the efficiency of the proposed methods.     

Data filtering based least squares algorithms for multivariable CARAR-like systems

This paper focuses on the identification problem of multivariable controlled autoregressive autoregressive (CARAR-like) systems. The corresponding identification model contains a parameter vector and a parameter matrix, and thus the conventional least squares methods cannot be applied to directly estimate the parameters of the systems. By using the hierarchical identification principle, this paper presents a hierarchical generalized least squares algorithm and a filtering based hierarchical least squares algorithm for the multivariable CARAR-like systems. The simulation results show that the two hierarchical least squares algorithms are effective.     

基于BP网络的机场助航故障灯检测

恒流调光器是为飞机起降提供目视引导的关键设备。对回路中故障灯的准确及时检测是调光器的重要功能。有关调光器的国际标准以及国标对该设备的功能均有严格要求,然而相关资料尚属鲜见难于借鉴。文中对这一课题进行了探讨,利用BP神经网络对调光器回路中的故障,进行监测并测算故障灯数目。实践表明,文章所用方法能有效地监测调光器故障,并能准确报告故障灯数目。     

高职高专《计算机应用基础》教学的思考

通过对高职高专<计算机应用基础>教学情况进行调查和分析,目前该课程教学中存在着诸多问题.解决这些问题,必须对其教学进行大胆改革和创新,以适应高职高专计算机基础教育的发展,为加快我国信息化进程做贡献.