A new method to evaluate human-robot system performance

One of the key issues in space exploration is that of deciding what space tasks are best done with humans, with robots, or a suitable combination of each. In general, human and robot skills are complementary. Humans provide as yet unmatched capabilities to perceive, think, and act when faced with anomalies and unforeseen events, but there can be huge potential risks to human safety in getting these benefits. Robots provide complementary skills in being able to work in extremely risky environments, but their ability to perceive, think, and act by themselves is currently not error-free, although these capabilities are continually improving with the emergence of new technologies. Substantial past experience validates these generally qualitative notions. However, there is a need for more rigorously systematic evaluation of human and robot roles, in order to optimize the design and performance of human-robot system architectures using well-defined performance evaluation metrics. This article summarizes a new analytical method to conduct such quantitative evaluations. While the article focuses on evaluating human-robot systems, the method is generally applicable to a much broader class of systems whose performance needs to be evaluated.     

A new algorithm for testing diagnosability of fuzzy discrete event systems

Failure diagnosis and detection of fuzzy discrete event systems play a significant role in the study of complex systems. In this paper, we investigate the diagnosability of fuzzy discrete event systems by proposing a new algorithm based on the concept of undistinguishable strings. Moreover, a necessary and sufficient condition for fuzzy diagnosability is obtained in terms of certain properties of the diagnoser, which is constructed with respect to the minimal observable event. The computing process to check the diagnosability of fuzzy DESs and some examples serving to illuminate the applications are developed and described.     

Checking p-t diagnosability of a system

In this paper the probabilistic measure of diagnosability, p-t diagnosability, originally proposed in [11], is used to study the diagnosability of digital systems. The system is represented by the graph theoretic model and assuming that failure probability of each unit is a priori known, a new necessary and sufficient condition has been proposed to check the p-t diagnosability of the system.     

Relative diagnosability of discrete-event systems and its opacity-based test algorithm

International Journal of Control, Automation and Systems - The notion of relative diagnosability is proposed for logical automata and the concept of diagnosable rate is introduced to characterize...     

新一代军用航空总线系统测试方法研究

为确保新一代军用航空总线系统——军用1394总线的性能及功能正确性、总线协议符合性及系统应用可靠性,对总线进行系统测试成为必要。搭建总线系统测试平台,从总线电气特性、总线协议符合性、系统应用方面对总线系统测试方法进行研究,经过总线系统的联试、试验及试飞任务,充分表明所描述的系统测试方法有效、可行,为新一代航空系统的飞行安全提供了可靠性保障。     

Cross-fuzzy entropy: A new method to test pattern synchrony of bivariate time series

A new method, namely cross-fuzzy entropy (C-FuzzyEn) analysis, that can enable the measurement of the synchrony or similarity of patterns between two distinct signals, is presented in this study. With the inclusion of fuzzy sets, the similarity of vectors is fuzzily defined in C-FuzzyEn based on the exponential function and their shapes, rather than on the Heaviside function used in the conventional cross sample entropy (C-SampEn). Tests on simulated data sets and real EEG signals showed that C-FuzzyEn was superior to C-SampEn in several aspects, including giving the entropy definition in the case of small parameters, better relative consistency, and less dependence on record length. The proposed C-FuzzyEn was then applied for the analysis of simultaneously recorded electromyography (EMG) and mechanomyography (MMG) signals during sustained isometric contraction for monitoring local muscle fatigue. The results showed that the C-FuzzyEn of EMG-MMG signals decreased significantly during the development of muscle fatigue. The C-FuzzyEn showed a similar trend with the mean frequency (MNF) of EMG, the commonly used muscle fatigue indicator. However, C-FuzzyEn of EMG-MMG demonstrated a better robustness to the length of the analysis window in comparison with the MNF of EMG. The results suggested that the proposed C-FuzzyEn of EMG-MMG may potentially become a new reliable method for muscle fatigue assessment. It can also be applied to other bivariate signals extracted from complex systems with short data lengths in noisy backgrounds.     

A new measurement method for the static test of ADCs

In this paper, a new method for the static test of analog-to-digital converters (ADCs) is proposed. This method uses a variable step size calculated by using an extrapolated convergence factor method. It is shown that it speeds up dramatically the static characterisation procedure and that it could substitute with advantage the traditional static test procedure, especially when a small step size is used.Results obtained by different methods as a function of the step size, of the number of samples and of the relation between the ADC resolution and the expected standard deviation of the noise present in the experimental setup, are shown.     

虚拟现实软件系统开发方法研究

虚拟现实技术是一门综合性技术,涉及计算机图形学、多媒体技术、人机交互和人工智能等多个领域,在教育、医疗、娱乐、军事等众多领域有非常广泛的应用。所有这些技术和应用最终都要靠计算机软件来实现,这就使得虚拟现实系统的软件变得十分庞大和复杂,涉及许多多媒体数据。传统软件开发方法和程序设计技术侧重于处理文本数据,显然不能满足开发虚拟现实软件的需要。试图以所在团队研发成功的PAR方法和PAR平台为基础,根据虚拟现实软件系统的特征,探寻虚拟现实软件系统开发的新方法,进一步扩充和完善PAR平台中已有多媒体处理技术、形式化建模技术和C#等高级语言程序自动生成系统。     

A new colour vision test in a PC-based screening system

The most commonly used method to examine the ability of the visual system to discriminate colours and detect colour vision deficiencies is based on pseudoisochromatic plates, such as the Ishihara plates. We describe a computer-based method to determine red–green colour deficiencies based on an anomaloscope simulator, which gave good results in a study of red–green discrimination is studied. It was shown experimentally that this computer-based method discriminates between subjects with colour deficiencies and subjects without colour deficiencies.     

A review of the diagnosability of control systems with applications to spacecraft

To achieve the safe, reliable autonomous operation of spacecraft, research on the fault diagnosis of control systems has attracted the attention of engineers and academicians throughout the aerospace field. Diagnosability can characterize the fault diagnosis capability of control systems. Connecting diagnosability analysis to the design of a spacecraft control system’s structure and diagnosis method can fundamentally improve the system’s fault diagnosis capability, improving the safety and reliability of autonomous spacecraft operation. In this paper, the diagnosability of spacecraft control systems is systematically studied from five perspectives: necessity, the current research status, the connotation, a novel index system and current development trends of diagnosability. First, the current status of spacecraft reliability analysis and reliability-based design is briefly reviewed, and existing problems are described, highlighting the advantages and importance of diagnosability research. Furthermore, the basic concepts of diagnosability are briefly introduced. By analyzing the current status of existing research on the diagnosability of both general and spacecraft control systems, the application scope of the diagnosability of spacecraft control systems is summarized. Moreover, the definition and influencing factors of the diagnosability of spacecraft control systems are presented to refine existing concepts, and a universal evaluation index system is proposed for the diagnosability of spacecraft control systems to further enhance the applicability of diagnosability evaluation and diagnosability-based design to spacecraft. Finally, the existing shortcomings and future development trends of diagnosability research for spacecraft control systems are discussed.     

A polynomial algorithm for testing diagnosability of discrete-eventsystems

Failure diagnosis in large and complex systems is a critical task. In the realm of discrete-event systems, Sampath et al. (1995) proposed a language based failure diagnosis approach. They introduced the diagnosability for discrete-event systems and gave a method for testing the diagnosability by first constructing a diagnoser for the system. The complexity of this method of testing diagnosability is exponential in the number of states of the system and doubly exponential in the number of failure types. We give an algorithm for testing diagnosability that does not construct a diagnoser for the system, and its complexity is of fourth order in the number of states of the system and linear in the number of the failure types     

一种新的存储解决方案——IND系统存储

文章分析了DAS、NAS、SAN三大存储方案及其优劣，特别是共同存在的服务器性能瓶颈与单点故障问题，提出了一种新的IND系统存储解决方案，并分析了这种存储方案的原理、特点。在对几种存储方案进行比较后，认为IND系统是一种很有发展潜力的存储解决方案。     

一种降低OFDM系统峰均比新方法

文章简要分析了正交频分复用(OFDM)系统中峰均比(PAPR)的成因,并提出了一种新的基于加扰技术的方法.仿真结果表明,该方法能够较好的抑制OFDM系统的峰均比,且具有复杂度低,易实现等优点.     

A diagnosability analysis by means of fault distance

A new concept of fault distance is introduced in a failure-diagnosis model. Diagnosability measures such as t-fault diagnosability and t/s-diagnosability are expressed in terms of the fault distance. A new diagnosability measure of partial t-fault diagnosability characterized in terms of fault distance is proposed. In addition, the fault distance of various types of self-diagnosis models are expressed in graph theoretical terms. Applying the fault distance to various types of self-diagnosis models, conditions for diagnosabilities of these models, which have been studied separately, are obtained in a unified manner. Conditions for t-fault diagnosability and sufficient conditions for t/s-diagnosability are obtained with this fault distance.     

高速GJB289A总线系统测试方法研究

随着航空电子技术的发展,原有的1 Mb/s总线传输速率已无法满足机载总线数据传输要求,高速GJB289A数据总线技术应运而生。为了保证高速GJB289A总线功能、性能的正确性,总线协议的符合性以及系统通信的可靠性,研究高速GJB289A总线系统的测试方法非常必要。主要从高速GJB289A总线系统电气特性、总线协议符合性、系统通信三方面实现对高速GJB289A总线系统测试方法的研究,介绍高速GJB289A总线系统测试平台搭建与测试方法,为后续高速GJB289A总线系统的设计、开发及研制奠定基础。     

UHF射频识别系统读写器仿真测试的研究

本文对超高频段射频识别系统的读写器进行了仿真测试的研究,利用matlab建立了读写器的系统模型,对读写器发射信号进行了时域和频域仿真。针对射频识别系统信号的非平稳性,对读写器暂态信号进行了联合时频分析。     

A New Classification Method to Overcome Over—Branching

Classification is an important technique in data mining.The decision trees builty by most of the existing classification algorithms commonly feature over-branching,which will lead to poor efficiency in the subsequent classification period.In this paper,we present a new value-oriented classification method,which aims at building accurately proper-sized decision trees while reducing over-branching as much as possible,based on the concepts of frequent-pattern-node and exceptive-child-node.The experiments show that while using relevant anal-ysis as pre-processing ,our classification method,without loss of accuracy,can eliminate the over-branching greatly in decision trees more effectively and efficiently than other algorithms do.     

一种新的证据冲突分析方法

当证据高度冲突时,使用DS组合规则经常会得到错误的结果,因此对DS证据理论的合成方法进行改进成为人们研究的重点.但是如何去度量或确定证据之间冲突的程度却常常被人忽视.在以往的研究中均使用冲突系数k作为表征证据之间冲突的量,但是研究结果表明,k不能很好的描述证据之间的冲突.对表征证据冲突的变量进行了研究,提出了一种新的表征证据之间冲突的变量-关联系数,基于偏熵和混合熵,定义了关联系数,该系数可以定量的表示证据之间的冲突.当关联系数接近1时证据之间冲突很小,当关联系数接近0时证据之间高度冲突.算例验证了所提出的基于关联系数的冲突表示方法的有效性.     

A method to test concurrent systems using architectural specification

In this paper, we discuss a testing method for integration testing of complex and concurrent systems. Integration testing is considered the least well understood and hence is the most problematic level of testing related to concurrent system development. This is so, because integration testing is not completely unit (or code) neither testing nor it is completely system testing. To achieve this goal of improving integration testing, our proposed method exploits architectural specification of concurrent and distributed systems defined in the high level Petri nets, known as Hierarchical Predicate Transition Nets (HPrTNs). More specifically, our testing method implements the separation of concerns strategy to handle both the essential complexity associated with the front-end software development of inherently concurrent and distributed systems, i.e. architectural specification, and the difficulty and cost associated with the back-end development of these systems, namely, software testing.