基于事件图的并行离散事件仿真方法

为解决并行离散事件仿真技术开发难度大的问题,提出一种基于事件图的并行离散事件仿真方法。采用模型驱动体系结构,利用转换器将事件图模型自动转换为基于逻辑进程的并行离散事件仿真可执行代码。并行离散事件仿真的建模方式由以代码为中心的模式发展为以模型为中心的模式。实验结果表明,该方法能提高并行离散事件的仿真效率。     

基于组件的舰载近程防御系统仿真研究

针对常规舰载近程防御仿真系统移植性较差的问题,充分利用组件开发易扩展、可复用的优势,给出了一种舰载近程防御系统仿真设计方案.首先,给出了系统总体框架;采用接口和实现分离原理,构建了组件接口,并给出了接口函数的规范化定义;其次,采用类厂模式和动态加载方式,设计了系统仿真引擎.最后,通过舰载近程防御系统仿真系统试验,验证了设计方案的合理性和可行性.     

Component Based Simulation Environments of Distributed Discrete Event Simulation

Component based design is a software design method developing from object-oriented design. It uses hierarchical, rnodular ideas to analyze and design systerns. It improves the reusability of software, decreases the cost of system developments. This paper applies the ideas of component based software design and distributed discrete event simulation （DDES）, and puts forward simulation component model standards and distributed simulation method, and develops the simulation environment. This method allows the users to reuse existing models and to build simulation by assembling basic models. It is fit for modeling and simulating large and complex systems in especial domain such as communication network, and supports the reuse of models effectively. The simulation environment has good flexibility and expansibility.     

Event-driven grammars: relating abstract and concrete levels of visual languages

In this work we introduce event-driven grammars, a kind of graph grammars that are especially suited for visual modelling environments generated by meta-modelling. Rules in these grammars may be triggered by user actions (such as creating, editing or connecting elements) and in their turn may trigger other user-interface events. Their combination with triple graph transformation systems allows constructing and checking the consistency of the abstract syntax graph while the user is building the concrete syntax model, as well as managing the layout of the concrete syntax representation. As an example of these concepts, we show the definition of a modelling environment for UML sequence diagrams. A discussion is also presented of methodological aspects for the generation of environments for visual languages with multiple views, its connection with triple graph grammars, the formalization of the latter in the double pushout approach and its extension with an inheritance concept. This is a revised and extended version of a paper presented at the ICGT’04 conference, see [21].     

LAMOST焦面板数学建模与仿真

焦面板是大天区面积多目标光纤光谱天文望远镜的一个重要部件,它是一个球面孔群结构,孔的位置精度直接影响到系统的成像质量.建立焦面板孔群中心点位置的数学模型并进行仿真不仅是进行优化孔群分布的需要,也是进行后续数控加工的需要.空间球坐标投影算法,解决了在球面上近似均匀分布孔群的难题,并利用科学计算工具MATLAB进行了数学建模与仿真.最后给出了仿真结果和孔群中心点位置的三维坐标,并提出了其他的改进方案.结果表明,该算法能有效地提高焦面板的孔位精度,满足了LAMOST的需要.     

基于分布对象的离散事件仿真系统

分布对象技术将面向对象的概念揉合到分布计算中,使得基于对象的软件成员在分布异构环境中可重用、可移植和可互操作。文章把分布对象技术用于离散事件系统仿真中,通过对离散事件系统中分布对象的标识,分布对象间同步机制的讨论,提出了基于分布对象离散事件仿真系统的结构,定义了分布仿真对象的接口。     

事件图模型及其在分布交互式仿真中的扩展

随着离散事件仿真的不断发展,涌现出许多建模方法,事件图模型就是其中之一.事件图模型具备简单、通用、快速和可扩展等优点,因此首先对事件图基本结构、要素和图形进行介绍,然后针对复杂仿真的需求,在基本事件图基础上,借鉴面向对象的思想进行的扩展,增加封装、接听模式和桥对象等概念;最后为适用于分布交互式仿真,提出在事件图中增加镜像事件的概念.事件图是图形化的建模方法,为能对其进行清晰和无二义的描述,还采用了集合论的方法对事件图和扩展事件图分别进行刻画.     

Modelling Dynamic Software Architectures using Typed Graph Grammars

Several recent research efforts have focused on the dynamic aspects of software architectures providing suitable models and techniques for handling the run-time modification of the structure of a system. A large number of heterogeneous proposals for addressing dynamic architectures at many different levels of abstraction have been provided, such as programmable, ad-hoc, self-healing and self-repairing among others. It is then important to have a clear picture of the relations among these proposals by formulating them into a uniform framework and contrasting the different verification aspects that can be reasonably addressed by each proposal. Our work is a contribution in this line. In particular, we map several notions of dynamicity into the same formal framework in order to distill the similarities and differences among them. As a result we explain different styles of architectural dynamisms in term of graph grammars and get some better insights on the kinds of formal properties that can be naturally associated to such different specification styles. We take a simple automotive scenario as a running example to illustrate main ideas.     

弹库系统弹列运动建模与仿真

弹库系统是向舰炮发射系统补弹、供弹的复杂机电系统。该文以某型弹库系统为例，介绍了弹库系统的组成与功能，弹库系统的建模目标与内容，研究了弹库操控逻辑，弹列运动的基本规律，采用离散系统的分析方法，从弹列的状态描述变量、事件的描述函数和动作的功能函数三个方面，建立了弹列运动的模型，编制了仿真程序，实现了弹库操控与弹列运动基本算法。该仿真系统可用于弹库系统总体设计、弹列运动调度算法研究。     

IGM弧焊机器人工作站三维造型与仿真

分析了IGM弧焊机器人工作站的结构特点,在VC++开发环境下,使用OpenGL图形开发工具,建立了基本体素;采用面向对象的思想完成了工作站各个组成部分的三维实体造型,系统中分别建立了环境类、机架类、机器人类、变位机类及其派生类,并实现了该工作站基于微机的运动仿真。     

组件式仿真系统中基于Web的管理控制方法

介绍组件式仿真系统的结构和特点,提出基于Web的组件资源管理方法和组件式仿真系统管理方法。描述组件资源库的结构和仿真管理方法的工作原理,阐述仿真过程控制服务的设计思路和管控Web服务器的结构。分析结果表明,该方法能用于可扩展建模与仿真框架。     

面向对象的离散事件系统仿真软件的多线程实现

对象交互是近年来离散事件系统仿真中采用的一种比较先进的仿真建模方法。面向对象技术的采用,使它比传统的三种建模策略都更接近人的思维方式和实际系统的特征,因而建模能力较强。文章提出的多线程的实现方案,通过线程来模拟实际系统中各个独立地、并发地运行的实体,线程间通过消息传递相互影响,推进仿真进程,不仅提高了仿真效率,易于处理并发等复杂情况,也大大简化了软件的实现。     

制导兵器系统建模与仿真的校核、验证与认可

介绍模型校核、验证与认可的基本概念,研究制导兵器系统建模与仿真发ＶＶＡ技术方法。从系统工程观点出发,首先给出制导兵器系统仿真研究全生命周期框架,在此基础上探讨具体的ＶＶＡ技术。所给出的制导兵器系统建模与仿真的ＶＶＡ技术方法,可用来指导建模与仿真,对提高仿真系统的置信度、增加仿真结果可信性具有重要的意义。     

ProactiveCrowd: Modelling Proactive Steering Behaviours for Agent‐Based Crowd Simulation

How to realistically model an agent's steering behaviour is a critical issue in agent‐based crowd simulation. In this work, we investigate some proactive steering strategies for agents to minimize potential collisions. To this end, a behaviour‐based modelling framework is first introduced to model the process of how humans select and execute a proactive steering strategy in crowded situations and execute the corresponding behaviour accordingly. We then propose behaviour models for two inter‐related proactive steering behaviours, namely gap seeking and following. These behaviours can be frequently observed in real‐life scenarios, and they can easily affect overall crowd dynamics. We validate our work by evaluating the simulation results of our model with the real‐world data and comparing the performance of our model with that of two state‐of‐the‐art crowd models. The results show that the performance of our model is better or at least comparable to the compared models in terms of the realism at both individual and crowd levels.     

某型反舰导弹全弹道数字仿真建模方法研究

仿真技术是一门通用的支撑性技术,其核心内容是模型建立、验证和运行技术,当前已广泛应用于导弹武器系统的研制、鉴定和使用中。利用MATLAB/Simulink进行某型反舰导弹的仿真建模,使建模过程变得容易、直观和迅捷。分别对仿真模型的几个子系统进行定义,并对仿真结果进行了动态显示及分析。最后讨论了有关反舰导弹的仿真验模方法。     

面向对象的离散事件仿真核的设计和实现

用面向对象的方法设计了一个离散事件仿真核。该仿真核独立于具体的应用,并提供编程的接口,用户只需重新定义这些编程接口即可对各种离散事件系统进行仿真,从而显著地降低了建立仿真系统的复杂性。该仿真核用C 语言实现,文中给出了一个仿真实例。     

LNG船液货装卸系统仿真计算与实现

液化天然气(LNG)船液货装卸过程中,需严格控制装卸时间,但由于装卸系统的复杂性,设计装卸系统时很难准确得到LNG在管路中的流动状态平衡控制。针对上述问题,提出了一种面向LNG船液货装卸系统结构的计算方法,根据图论和有限元软件构建装卸系统拓扑模型,形成双层反馈控制结构,建立仿真装卸模型,计算任意时间点的管网节点压头和管路流量情况。采用Visual C++编制了图形化界面的仿真计算软件进行仿真。仿真结果与实际情况基本符合,表明装卸方法具有实用性,能对LNG船液货装卸系统的设计起借鉴作用。     

船舶压载系统仿真软件研究与设计

为了对船舶压载水系统的运行过程进行动态仿真与研究，建立了整个船舶压载水系统的仿真模型。具体地，依据工程流体力学的知识，并利用功率键合图的方式，建立了包括管网和基本元件的仿真模型。借助第三方的COM组件VisualGraph，利用VisualC#开发出压载水系统的动态仿真与监控软件。仿真软件将泵、阀、船舱等元件模块化，通过编辑等操作构建具体拓扑结构。操作员可以在此基础上进行压载舱注水、排水等仿真操作，同时对液位变化、泵阀开启、报警等情况进行监控。     

CEPSim: Modelling and simulation of Complex Event Processing systems in cloud environments

The emergence of Big Data has had profound impacts on how data are stored and processed. As technologies created to process continuous streams of data with low latency, Complex Event Processing (CEP) and Stream Processing (SP) have often been related to the Big Data velocity dimension and used in this context. Many modern CEP and SP systems leverage cloud environments to provide the low latency and scalability required by Big Data applications, yet validating these systems at the required scale is a research problem per se. Cloud computing simulators have been used as a tool to facilitate reproducible and repeatable experiments in clouds. Nevertheless, existing simulators are mostly based on simple application and simulation models that are not appropriate for CEP or for SP. This article presents CEPSim, a simulator for CEP and SP systems in cloud environments. CEPSim proposes a query model based on Directed Acyclic Graphs (DAGs) and introduces a simulation algorithm based on a novel abstraction called event sets. CEPSim is highly customizable and can be used to analyse the performance and scalability of user-defined queries and to evaluate the effects of various query processing strategies. Experimental results show that CEPSim can simulate existing systems in large Big Data scenarios with accuracy and precision.     

Inverse Procedural Modelling of Trees

Procedural tree models have been popular in computer graphics for their ability to generate a variety of output trees from a set of input parameters and to simulate plant interaction with the environment for a realistic placement of trees in virtual scenes. However, defining such models and their parameters is a difficult task. We propose an inverse modelling approach for stochastic trees that takes polygonal tree models as input and estimates the parameters of a procedural model so that it produces trees similar to the input. Our framework is based on a novel parametric model for tree generation and uses Monte Carlo Markov Chains to find the optimal set of parameters. We demonstrate our approach on a variety of input models obtained from different sources, such as interactive modelling systems, reconstructed scans of real trees and developmental models.