ESD模拟器的应用研究

将ESD模拟器用金属网罩屏蔽,可减小模拟器内部继电器开关的电磁干扰.但屏蔽前后电流产生场变化不大,屏蔽后的辐射场场峰值仅稍低于未屏蔽的场.用该模拟器进行单片机系统的ESD抗扰度实验,发现屏蔽前后,同故障现象出现的最小放电电压值相差几千伏,即模拟器内部继电器开关产生的辐射场对实验结果有影响.这说明IEC标准仅仅规定ESD放电电流的波形是不够的,应对放电场做出相应规定.     

Active-reactive scheduling of activedistribution system considering interactiveload and battery storage

The increasing penetration of inverter-based distributed generations (DGs) significantly affects the fault characteristics of distribution networks. Fault analysis is a keystone for suitable protection scheme design. This paper presents the modelling methodology for distribution networks with inverter-based DGs and performs fault simulation based on the model. Firstly, a single inverter-based DG model based on the cascaded control structure is developed. Secondly, a simulation model of distribution network with two inverter-based DGs is established. Then, different fault simulations are performed based on the Real Time Digital Simulator (RTDS). Theoretical analyses are conducted to justify the simulation results, including the equivalent circuit of distribution networks with inverter-based DGs and the solution method for loop currents     

Human error probability estimation by coupling simulator data and deterministic analysis

Operator error in diagnosis and execution of task have significant impact on Nuclear Power Plant (NPP) safety. These human errors are classified as mistakes (rule base and knowledge based errors), slip (skill based) and lapses (skill based). Depending on the time of occurrence, human errors have been categorized as i) Category ‘A’ (Pre-Initiators): actions during routine maintenance and testing wherein errors can cause equipment malfunction ii) Category ‘B’ (Initiators): actions contributing to initiating events or plant transients iii) Category ‘C’ (Post-Initiators): actions involved in operator response to an accident. There have been accidents in NPPs because of human error in an operator's diagnosis and execution of an event. These underline the need to appropriately estimate HEP in risk analysis. There are several methods that are being practiced in Probabilistic Safety Assessment (PSA) studies for quantification of human error probability. However, there is no consensus on a single method that should be used. In this paper a method for estimating HEP is proposed which is based on simulator data for a particular accident scenario. For accident scenarios, the data from real NPP control room is very sparsely available. In the absence of real data, simulator based data can be used. Simulator data is expected to provide a glimpse of probable human behavior in real accident situation even though simulator data is not a substitute for real data. The proposed methodology considers the variation in crew performance time in simulator exercise and in available time from deterministic analysis, and couples them through their respective probability distributions to obtain HEP. The emphasis is on suitability of the methodology rather than particulars of the cited example.     

ATMSim: An anomaly teletraffic detection measurement analysis simulator

Over the last few years, the quantity of teletraffic is rapidly growing because of the explosive increase of Internet users and its applications. The needs of collection, storage, management, analysis, and measurement of the subsequent teletraffic have emerged as some of the very important issues. To this point many studies for detecting anomaly teletraffic have been done. Detection, measurement, and analysis studies for traffic data, however, are not actively being made based on Hadoop. In this paper, some problems and solutions for those systems have been suggested. We have also designed and developed an Anomaly Teletraffic detection Measurement analysis Simulator, called the ATMSim. One strong point of the ATMSim is able to store, measure, and analyze traffic data for detecting anomaly teletraffic. The other strength is to generate sequences of input synthetic anomaly teletraffic with various network attacks for practical network security applications. All simulations were executed under the control of the ATMSim simulator to investigate how input anomaly teletraffic with network attacks can be different from real Ethernet local area network (LAN) traffic. Our numerical results show that the values of the estimated Hurst parameter obtained from the anomaly teletraffic are much higher when compared to real Ethernet LAN traffic.     

The sensitivity of laboratory tests assessing driving related skills to dose-related impairment of alcohol: A literature review

Laboratory tests assessing driving related skills can be useful as initial screening tools to assess potential drug induced impairment as part of a standardized behavioural assessment. Unfortunately, consensus about which laboratory tests should be included to reliably assess drug induced impairment has not yet been reached. The aim of the present review was to evaluate the sensitivity of laboratory tests to the dose dependent effects of alcohol, as a benchmark, on performance parameters. In total, 179 experimental studies were included. Results show that a cued go/no-go task and a divided attention test with primary tracking and secondary visual search were consistently sensitive to the impairing effects at medium and high blood alcohol concentrations. Driving performance assessed in a simulator was less sensitive to the effects of alcohol as compared to naturalistic, on-the-road driving. In conclusion, replicating results of several potentially useful tests and their predictive validity of actual driving impairment should deserve further research. In addition, driving simulators should be validated and compared head to head to naturalistic driving in order to increase construct validity.     

基于IODELAY原语SAR载荷模拟器延迟单元设计

针对星载合成孔径雷达中数传分系统接收数据时序拉偏测试需求,本文提出一种基于FPGA原语的SAR载荷模拟器延时单元设计与实现。该延迟单元采用IODELAY原语,通过时序约束实现正反向时钟拉偏功能。仿真与试验结果表明,该延迟单元时序调整范围可达-6ns至6ns,步进1ns,系统运行稳定,满足设计要求。     

Geographically distributed real-time digital simulations using linear prediction

Real-time (RT) simulator is a powerful tool for analyzing operational and control algorithms in electric power systems engineering. For understanding the dynamic and transient behavior of a power systems, significant RT computation capabilities are essential. A single unit of RT simulator has limited simulation capabilities. The most common way of augmenting simulation capability is using a bank of locally connected RT simulators. However, creating a large-sized bank of RT simulators involves significant financial investments and hence may not be feasible at all research facilities. Power and energy systems research facilities that use RT simulators are at diverse physical locations. In addition to RT simulators, research facilities around the world house an array of facilities with unique power, energy, and control systems for innovative research. To leverage these unique research facilities, geographically distributed RT simulation based on Wide Area Network (WAN) is required. Typical RT simulators perform simulations with time-steps in the order of milliseconds to microseconds, whereas data latency for communication on WAN may be as high as a few hundred milliseconds. Such communication latency between RT simulators may lead to inaccuracies and instabilities in geographically distributed RT simulations. In this paper, the effect of communication latency on geographically distributed RT simulation is discussed and analyzed. In order to reduce the effect of the communication latency, a Real-Time Predictor (RTP), based on linear curve fitting is developed and integrated into the distributed RT simulation environment. Two geographically distributed digital RT simulators are used to perform dynamic simulations of an electric power system with a fixed communication latency and the predictor. Empirical results demonstrate the effects of communication latency on the simulation and the performance of the RTP to improve the accuracy of simulations.     

SDMSim: A manufacturing service supply–demand matching simulator under cloud environment

Nowadays, with the introduction and application of new information technologies in manufacturing, various advanced manufacturing modes and national strategies have been put forward and paid more and more attention, such as Industry 4.0, Industrial Internet, Cyber-Physical System or Cyber Manufacturing, Made in China 2025, Internet Plus Manufacturing, Cloud Manufacturing, etc. For these modes and strategies, how to realize the effective and intelligent supply–demand matching (SDM) of various manufacturing resources and capabilities (MR&C) in the form of service is one of the common issues and aims. In order to provide a uniformed research platform for related researchers both in academic and industry, the concept of manufacturing service SDM simulator (SDMSim) is proposed in this paper. A hypernetwork based architecture for the simulator is designed, as well as its seven key functions and subsystems, including manufacturing service management, manufacturing task management, manufacturing service SDM hypernetwork, manufacturing service SDM problem formulation and configuration, matching and scheduling algorithms/strategies selection and design, statistical analysis, and visualization. It illustrates that SDMSim has the potential to serve the users of manufacturing service provider, manufacturing service consumer, manufacturing service operator in the field of SoM, as well as the related researchers.     

手持数控编程/仿真器设计

介绍一种具有数控加工程序编辑、编译、存储、通讯和仿真等主要功能的手持式数控编程/仿真器设计方法.编程/仿真器内含国际标准GM代码,采用7×8按键矩阵、LCD显示和USB接口设计,通过显示加工轨迹可对加工程序进行验证调试.给出系统的硬件组成和软件设计,利用Proteus+KeilC实现联合仿真.结果表明:该编程/仿真器运行可靠,使用方便,适用于数控车床加工和高校数控教学培训,具有推广价值.