基于HLA的物资保障仿真系统研究

本文首先介绍了高层体系结构,然后结合物资保障活动,提出了"基于HLA的物资保障仿真系统",该系统采用HLA的仿真体系结构,模块化设计和编程,便于系统将来的功能扩展和代码重用.     

一种基于DEVS的网络设备仿真模型

在分析目前网络设备仿真建模所面临的主要问题的基础上,简要介绍了 DEVS 规范及其基本构成要素;以以太网交换机为实例,对基于 DEVS 的网络设备仿真建模技术进行了研究,并实现了仿真建模。对该网络设备建模方法的优点做了总结,并就此建模方法在网络设备建模中的应用前景进行了展望。     

DEVS的面向对象可视化建模

DEVS是对离散事件系统的一种形式化描述,该文在DEVS中引入面向对象的方法,并采用UML（Unified Modeling Language)对它进行可视化建模。文中提出了基于DEVS的面向对象的一种建模规则和基于UML的可视化建模思想和方法,该方法是对DEVS和UML的扩充和改进。     

基于Proteus的处理器C++建模与仿真

研究利用C++创建Proteus模型的方法,实现一个基于Proteus的自定义指令集仿真器模型,构建该模型的虚拟板级系统,并进行测试。实验结果表明,基于Proteus的处理器仿真器能在芯片RTL模型面世前构建虚拟板级系统,为芯片的功能测试提供更方便直观的平台,有利于芯片早期开发的软硬件协同设计。     

离散事件系统规范DEVS研究

离散事件系统是一类常见的系统,如何对这类系统进行描述与建模是离散事件系统仿真研究的核心内容。离散事件系统规范DEVS是一种离散事件系统形式化描述方法,它具有层次化和模块化的特点,利用该方法可对复杂的离散事件系统进行建模、设计、分析和仿真。该文详细介绍了DEVS基本模型和耦合模型,给出了DEVS在耦合运算下的封闭性构造证明,并提出了一种具有嵌套层次结构的DEVS耦合模型实现算法,该算法对基于DEVS描述的离散事件系统的仿真实现具有一定参考价值。     

基本作战单元预防性维修保障过程建模仿真

为分析评价基本作战单元预防性维修保障方案,计算分析预防性维修时间,根据系统工程建模思想描述了基本作战单元的预防性维修过程,提出了故障发生比、更换比和报废比参数,建立了仿真模型,并根据Monte Carlo仿真原理给出仿真算法,为型号工作人员和装备使用人员进行保障性分析提供了理论方法和技术手段,最后以某型飞机组成的基本作战单元为例,对其预防性维修保障方案进行仿真试验验证,分析了预防性维修过程的改进对保障资源和维修时间的影响.     

一种基于Modelica语言的混合系统DEVS模型架构

Modelica语言采用微分方程描述系统,此外它还具备面向对象编程语言的特性,因此它不仅适用于连续系统的建模,还支持离散系统的模型架构。因此,可以将Modelica作为一种混合系统的建模语言。提出了一个Modelica语言描述的DEVS（Discrete E Vent System specification离散事件系统规范）模型架构,并通过对模型的编译过程产生C＋＋代码,获取了同时描述连续系统和离散系统建模的能力。最后给出了用Modelica语言描述的一个飞机导航控制连续一离散仿真系统的例子。     

基于对象Petri网的离散事件系统建模仿真环境(OPMSE)

首先论述了Ｐｅｔｒｉ网和高级Ｐｅｔｒｉ网发展状况,提出了一种高级Ｐｅｔｒｉ网,即对象Ｐｅｔｒｉ网。然后介绍了基于对象Ｐｅｔｒｉ网的离散事件系统建模仿真环境ＯＰＭＳＥ。文中详细介绍了ＯＰＭＳＥ的特点与组成,并对ＯＰＭＳＥ的核心－对象Ｐｅｔｒｉ网（ＯＰＮ）的语法描述进行了重点介绍。     

防空系统建模仿真环境设计

该文通过对攻防对抗系统的特点和计算机建模仿真环境的研究,给出了描述攻防对抗系统仿真模型的通用模型定义,设计开发了一种能处理属性连续变化实体的攻防对抗离散事件建模与仿真环境。该软件采用面向对象的方法设计,提供给用户的是模块化、图形化的窗口环境,用户通过点击拖放工具箱中的单元就能构建出攻防对抗系统的模型,并能对其进行仿真实验。     

物资调运过程的PETRI网建模及仿真

本文对三峡工程水泥调运过程用ＰＥＴＲＩ网进行建模，指出了进行调运的关键库所和变迁。讨论了拌和浇筑环节 ＰＥＴＲＩ网模的可能存在的不良特性。为解决此类问题设计了仿真器，它很好地实现了调度模拟的功能。同时给出了仿真器的框架和ＤＳＰ怕仿真     

Distributed simulation of DEVS and Cell-DEVS models in CD++ using Web-Services

Discrete event system specification (DEVS) is a modeling and simulation formalism that has been widely used to study the dynamics of discrete event systems. Cell-DEVS is a DEVS-based formalism that defines spatial models as a cell space assembled of a group of DEVS models connected together. CD++ is a modeling and simulation toolkit capable of executing DEVS and Cell-DEVS models that has proven to be useful for executing complex models. We present the design and implementation of a distributed simulation engine, known as D-CD++, which exposes CD++ simulation utilities as machine-consumable services. In addition, we present the design and implementation of the Web-Service components which enable D-CD++ to expose the simulation functionalities to remote users. Enabling CD++ with Web-Services technology provides a solid framework for interoperating different DEVS implementations in order to achieve a standard DEVS Modeling Language and simulation protocols. This paves the road towards DEVS standardization, while providing a mashup approach, which can lead to higher degree of reuse and reduced time to set up and run experiments, and making sharing among remote users more effective. To prove this fact, we integrate it within larger services (such as a 3D visualization engine), showing the mechanism to incorporate to other environments (including geographical information systems, web-based applications and other modeling and simulation tools) through using standard Web-Service tools. Performance of D-CD++, major bottlenecks and communication overheads are analyzed.     

Multi-resolution modeling based on quotient space and DEVS

As simulation systems get more and more complex, the study of multi-resolution modeling (MRM) remains an exciting and fertile area of research. Contrasting its abundant successful use cases, a rigorous mathematical foundation is still lacking in MRM. In this paper, we propose a quotient space based multi-resolution modeling (QMRM) theory based on granular computing in artificial intelligence and on discrete-event system specification (DEVS) in modeling and simulation. Based on quotient sets, resolution, multi-resolution modeling and other related concepts are defined and a general concept framework is constructed. Based on the concepts of quotient set and natural projection, several MRM principles are derived. The internal consistency principle guarantees consistency among different perspectives of an atomic model, whereas the external consistency principle guarantees that different components in a coupled model are consistent. The false-preserving principle indicates that if a construction relation or state transformation relation of a component does not exist in a low resolution model, then the corresponding relations should not exist in its high resolution model. The true-preserving principle tells us that a high resolution model can be simplified by choosing the proper low resolution model. QMRM is not only a formal specification, but also a fundamental framework to understand MRM concepts, a guiding ideology to design specific MRM methods, and a modeling methodology to develop MRM systems. QMRM is created from a general simulation perspective, not limited by any specific application or problem domain aspects. The results of this paper can serve as a starting point for further study of multi-resolution problems in different domains.     

基于C++语言的雷达系统组件化建模与仿真

传统的基于面向过程式语言的雷达仿真系统存在功能耦合严重,运行速度慢,开发难度大的问题。为了降低雷达仿真系统的开发难度,提高程序复用性,利用C++语言面向对象编程的特性和软件工程中组件复用的思想,设计了一种基于C++语言的雷达系统建模与仿真方法,将雷达系统各个组成部分包括资源调度、发射机、天线、回波生成、接收机、信号处理和数据处理抽象成单个功能组件分别进行开发,然后根据雷达系统工作顺序将各个组件集成在一起,实现了一个包含雷达参数设置、场景设置、数据存储和显控终端的完整的雷达仿真系统。仿真实验结果表明组件化雷达仿真系统运行正确,目标探测误差符合要求,航迹显示正常,并且具有较好的程序复用性和扩展性,促进了现代雷达仿真的快速应用。     

多出救点、多物资应急调度算法研究

目前物资调度方法大多是针对单出救点、单物资的调度,不能满足应急救助的实际需要。讨论在满足时间与出救点数量的约束条件下,如何解决灾害发生地多种物资调度问题,同时解决灾害发生地和物资储备仓库之间的最短路径问题。给出了两个具体的算法,并用一个实例验证了算法的可行性。     

Distributed simulation of DEVS and Cell-DEVS models using the RISE middleware

With the expansion of the Web, the desire toward global cooperation in the distributed simulation technology has also been on the rise. However, since current distributed simulation interoperability methods are coupled with system implementations, they place constraints on enhancing interoperability and synchronization algorithms. To enhance simulation interoperability on the Web, we implemented the RISE (RESTful Interoperability Simulation Environment) middleware, the first existing simulation middleware to be based on RESTful Web-services (WS). RISE is a general middleware that serves as a container to hold different simulation environments without being specific to a certain environment. RISE can hold heterogeneous simulations, and it exposes them as services via the Web. One of such services is called Distributed CD++ (DCD++) simulation system, an extension of the CD++ core engine that allows executing DEVS and Cell-DEVS models. Here, we introduce a proof-of-concept design and implementation of DCD++ using the distributed simulation using the RISE environment. We show how the RESTful WS interoperability style in RISE has improved the design, implementation and the performance of the DCD++ simulator. We also discuss a substantial performance improvement of the implementation of the RISE-based DCD++ presented here, showing many advantages of the RESTful WS presented here: improved interoperability, a seamless method to be connected into a cloud computing environment, and performance improvement when compared to our SOAP-based DCD++ in a similar testing environment.     

An advanced supply chain management tool based on modeling and simulation

The paper presents an advanced modeling approach and a simulation model for supporting supply chain management. The first objective is to develop a flexible, time-efficient and parametric supply chain simulator starting from a discrete event simulation package. To this end we propose and advanced modeling approach. The second objective is to provide a decision making tool for supply chain management. The simulator is a decision making tool capable of analyzing different supply chain scenarios by using an approach based on multiple performance measures and user-defined set of input parameters. Our simulator capabilities as decision making tool are strongly amplified if Design of Experiment (DOE) and Analysis of Variance (ANOVA) are respectively used for experiments planning and simulation results analysis. With regard to supply chain decision making process, we propose an application example for a better understanding of tool potentials. The application example considers a specific supply chain scenario and analyzes the effects of inventory control policies, lead times, customers’ demand intensity and variability, on three different supply chain performance measures.     

基于OMNeT++的"实代码"仿真模式研究

尝试搭建一个基于OMNeT++仿真器的"实代码仿真模式"的研究,将整套UCOS系统上运行的协议代码封装成动态链接库,加载到仿真器上利用其离散仿真事件队列机制进行调试,运行通过后可以直接在实际硬件芯片上运行,无需二次修改,大大提高研究开发进度.成功地将UCOS上运行的aloha协议栈封装成DLL加载到OMNeT++,调试运行通过并且已经投入到实际应用中.     

基于agent行为的供应链低碳化建模与仿真

从供应链低碳化出发,分析了企业碳配额、碳交易市场中的碳价格以及消费者主观购买行为等因素对企业利润的影响。采用Repast Simphony实验仿真平台和Groovy开发语言,在复杂的不确定市场环境下,对供应链参与方行为进行仿真,建立了引入碳交易因素以后的供应链模型。模型中包含消费者对产品的选择、低碳化运输和采购、供应商选择等市场行为。仿真结果表明,企业碳配额和消费者主观购买行为对企业利润的影响较大,对碳交易市场中的碳价格影响较小,初步验证了模型的有效性。     

基于Agent UML的企业供需网系统建模

在对多功能开放型企业供需网的复杂适应系统特征进行分析的基础之上,运用扩展UML的Multi-Agent系统建模方法--Agent UML建立了多功能开放型企业供需网的动态模型.分析多功能开放型企业供需网的复杂适应系统特点,建立供需网的多智能自主体系统结构,应用Agent UML建模方法分析了供需网多智能体系统中角色的静态结构关系和动态行为.在此基础上,建立了供需网动态交互行为模型.     

基于Visual C++的总线型局域网仿真软件设计

为了控制P-坚持CSMA/CD总线型局域网络的响应时间,通过面向对象建模,采用离散事件仿真方法设计,采用V isual C++编程实现了对总线型局域网的仿真。通过仿真结果分析了概率P对网络性能的影响,要想提高网络的综合性能指标,必须综合考虑在不同的负荷下P值对各指标的影响。