数字图象系统及其在材料分析与测试中的应用

本文简要地介绍了通用数字图象分析系统的发展过程及其应用。并着重阐明其在材料科学领域中有关材料分析及测试方面的应用,而且介绍了作者研制的能进行材料图象分析、测量和统计的应用软件包的主要内容。     

关于拟动态安全域的理论分析

本文引入拟动态安全域来刻画电力系统稳定性。若电力系统当前运行状态位于拟动态安全域内,则该系统经历事故后仍然是稳定的。太文通过分析事故中系统轨道的性质,讨论了拟动态安全域的拓扑性质,为拟动态安全域的应用提供了理论基础。     

企业信息系统应用集成的语义模型方法

分析了企业信息系统应用集成中存在的语法及语义不一致问题,将基于本体的语义模型引入到企业信息系统解决集成问题的方案中.依据企业语义模型组织进行5个层次划分的思想,对纵向一体化的供应链企业间信息系统应用集成建模提供指导思想.     

大规模海上风电场输电方式的探讨

分析了大规模海上风电场的并网需求,比较了高压交流输电系统、基于电网换相换流器的高直流输电系统和电压源换流器的直流输电系统的技术特点,对系统损耗做了数值分析,从而得出各种输电系统的适用范围。     

Application of the integrated safety assessment methodology to the protection of electric systems

The generalization of classical techniques for risk assessment incorporating dynamic effects is the main objective of the Integrated Safety Assessment Methodology, as practical implementation of Protection Theory. Transient stability, contingency analysis and protection setpoint verification in electric power systems are particularly appropriate domains of application, since the coupling of reliability and dynamic analysis in the protection assessment process is being increasingly demanded. Suitable techniques for dynamic simulation of sequences of switching events in power systems are derived from the use of quasi-linear equation solution algorithms. The application of the methodology, step by step, is illustrated in a simple but representative example.     

含硼酸基团环境响应型高分子聚合物的研究进展

系统综述了含硼酸基团的环境响应型高分子聚合物在药物缓释领域及生物医药领域中的研究进展。对含苯硼酸基团的智能高分子系统:聚乙烯醇-硼酸(PVA-PBA)系统,N-异丙基丙稀酰胺-3-丙稀酰胺苯硼酸(NIPAAm-AAPBA)系统,以及其它含氨基的高分子和3-丙烯酰胺苯硼酸共聚系统对环境敏感度及系统的相应变化,与其在药物控释中的应用作了较详细的论述和比较。并对含硼酸基团的高分子系统在生物医药领域中的应用做了一定的概述。     

The combined use of data and expert estimates in population variability analysis

Bayesian population variability analysis, also known as the first stage in two-stage Bayesian updating [IEEE Trans. Power Appar. Syst. PAS-102 (1983) 195] or hierarchical Bayes [Bayesian reliability analysis, 1991], is an estimation procedure for the assessment of the variability of reliability measures among a group of similar systems. Variability distributions resulting from this form of analysis find application as generic prior distributions in system-specific Bayesian reliability assessments. This paper presents an extension of the Bayesian approach to population variability analysis, which concerns the introduction of sources estimates (e.g. engineering judgment) as one of the forms of evidence used in the construction of population variability distributions. The paper presents the model, and illustrates its behavior by means of a practical example.     

Analysis and characterization of alignment for free-space optical interconnects based on singular-value decomposition

We propose a theoretical method to analyze and characterize the alignment of optical systems by using a singular-value decomposition (SVD) technique. One application of this method is to identify critical parameters for alignment systematically during alignment of two-dimensional device arrays. Another example application is to characterize the sensitivity or the accuracy of the misalignment-detection capability by evaluation of the singular values of optical systems. The information obtained through SVD-based techniques yields critical insights into the analysis of alignment.     

The Demon–Angel method in systematic safety assessment

Since ‘design for safety' of large engineering systems with a high level of innovation requires an exhaustive safety analysis and since a subsequent corrective action may become a very large bottleneck in improving such a system, fundamental knowledge in designing safe systems is essential. The lack of any ‘rule of thumb' makes such knowledge a matter of personal experience rather than the subject of an academic course. This paper proposes a new method for the theoretical safety study of different system configurations independently of any particular application. This method aims to help the construction of a ‘rule of thumb' for what is a safe system and what is not. The Demon and Angel ideas are explained and the schematic presentation of these elements is introduced. Four representative case studies demonstrate the use of this method.     

Quantitative biology of single neurons

The building blocks of complex biological systems are single cells. Fundamental insights gained from single-cell analysis promise to provide the framework for understanding normal biological systems development as well as the limits on systems/cellular ability to respond to disease. The interplay of cells to create functional systems is not well understood. Until recently, the study of single cells has concentrated primarily on morphological and physiological characterization. With the application of new highly sensitive molecular and genomic technologies, the quantitative biochemistry of single cells is now accessible.     

Redundancy and robustness of systems of events

The article aims to add a new impetus to rational and objective probabilistic evaluation of redundancy and robustness, based on uncertainties of systems and subsystems of events. An attempt is made to demonstrate the relevance of intuitive comprehension of redundancy and robustness of engineering systems of events. An event-oriented system analysis of a number of random observable operational and failure modes, with adverse probability distributions in a lifetime, may provide a deeper understanding of systems operational abundance and endurance. The system uncertainty analysis is based on the concept of entropy as defined in information theory and applied to probability theory. The article relates reliability, uncertainty, redundancy and robustness of systems of events and their application is illustrated in numerical examples.     

Adjoint operator approach to functional reliability analysis of passive fluid dynamical systems

Reliability analysis of passive systems mainly involves quantification of the margin to safety limits in probabilistic terms. For systems represented by complex models, propagating input uncertainty to get the response uncertainty and hence probability information requires intensive computational effort. Here a computationally efficient method for the functional reliability analysis of passive fluid dynamical systems is presented. The approach is based on continuous adjoint operator technique to generate a response surface approximating the given system model from the sensitivity coefficients. A numerical application of this method to the reliability analysis of heat transport in an asymmetrical natural convection loop is demonstrated. Computational efficiency and accuracy compared with the direct Monte-Carlo and forward response surface methods.     

On Cost‐effective Reuse of Components in the Design of Complex Reconfigurable Systems

Design strategies that benefit from the reuse of system components can reduce costs while maintaining or increasing dependability—we use the term dependability to tie together reliability and availability. D3H2 (aDaptive Dependable Design for systems with Homogeneous and Heterogeneous redundancies) is a methodology that supports the design of complex systems with a focus on reconfiguration and component reuse. D3H2 systematizes the identification of heterogeneous redundancies and optimizes the design of fault detection and reconfiguration mechanisms, by enabling the analysis of design alternatives with respect to dependability and cost. In this paper, we extend D3H2 for application to repairable systems. The method is extended with analysis capabilities allowing dependability assessment of complex reconfigurable systems. Analysed scenarios include time‐dependencies between failure events and the corresponding reconfiguration actions. We demonstrate how D3H2 can support decisions about fault detection and reconfiguration that seek to improve dependability while reducing costs via application to a realistic railway case study. Copyright © 2017 John Wiley & Sons, Ltd.     

时间计量理论及其发展

时间作为基本的物理量之一,在科学研究、国防与经济建设以及人们日常生活中发挥着重要作用。通过系统回顾时间计量系统的发展历程,详细阐述了各时期时间计量系统建立的理论基础与方法,研究了各种时间尺度的定义及具体实现,给出了各时间系统之间的转换关系,分析梳理了各自的优缺点,并对计时系统未来可能的发展方向作了展望。对于系统学习并深入理解时间计量理论发展历史与高精度时间计量数据处理与应用具有一定参考价值。     

Branching-type polling systems with large setups

The present paper considers the class of polling systems that allow a multi-type branching process interpretation. This class contains the classical exhaustive and gated policies as special cases. We present an exact asymptotic analysis of the delay distribution in such systems, when the setup times tend to infinity. The motivation to study these setup time asymptotics in polling systems is based on the specific application area of base-stock policies in inventory control. Our analysis provides new and more general insights into the behavior of polling systems with large setup times.     

An efficient exact procedure for the analysis of the state-dependent polling model

Polling models are used to model and analyze systems in which a single server attends to multiple queues at which requests arrive for service. State-Dependent (SD) polling models form a class of polling models in which the server performs a setup at a polled queue only if that queue is non-empty. SD polling models facilitate the analysis of many real-world systems. For example, recent developments in the field of radio frequency data communication, with its application to warehouse management and material handling systems, will provide a significant impetus to research on SD polling models. Exact analysis of the SD polling model is, however, inherently complex. The lack of an efficient exact procedure to analyze the SD polling model has hitherto limited its application, with real-world systems typically being modeled by the simpler state-independent polling model. Naturally, that results in a loss of modeling power and provides questionable values for desired performance measures. In this paper, we present an efficient exact analytic technique to compute the desired performance measures for the SD polling model.     

Analysis of storage assignment policies in less than unit load warehousing systems

Analytical models for the analysis of item location policies in unit load storage and retrieval systems are extended to less than unit load warehousing systems. The models are used to compare dedicated storage using cube per order index item dispatching and randomized storage using closest open location item dispatching with respect to total item space requirements, orderpicking cycle times and system responsiveness. Despite a number of computational limitations, it is argued that the models provide practical tools for analysis of less than unit load systems prior to development of simulation-based models or for validation of simulation-generated model results. The application of the models are demonstrated for a sample problem.     

How to Perform Continuous Sampling (CSP), Vol. 2: ASQC Basic Reference Series

Modeling recurrent event data is of current interest in statistics and engineering. This article proposes a framework for incorporating covariates in flowgraph models, with application to recurrent event data in systems reliability settings. A flowgraph is a generalized transition graph (GTG) originally developed to model total system waiting times for semi-Markov processes. The focus of flowgraph models is expanded by linking covariates into branch transition models, enriching the toolkit of available data analysis methods for complex stochastic systems. This article takes a Bayesian approach to the analysis of flowgraph models. Potential applications are not limited to engineering systems, but also extend to survival analysis.     

Special issue: Reliability management of complex system

Nowadays,reliability is moving toward interdisciplinary research with ever-increasing connotations for full life-cycle system management,including system design,analysis,modeling,test,operation,optimization,etc.Meanwhile,complex systems,such as transportation system,power system,communication system and other various critical infrastructure systems,have posed a big challenge,which attracts great attention both in theory and application.Characterized by nonlinear interaction,emergent response,and high dimensional coupling,the complex systems are in the face of extremely high uncertainty and vulnerability.Therefore,failure of these complex systems could cause even more dramatic cascading impacts,leading to huge losses of life and property.All these realities put forward more urgent requirements for the fundamental theory and specific application of reliability management of complex systems.