城轨车辆车载超级电容储能系统主要参数的选择

为了给城轨车辆车载超级电容储能系统主要参数的选择提供理论依据,本文将建立超级电容储能系统的仿真模型,选择超级电容储能系统的主要参数。然后通过matlab／simulink软件仿真,验证参数选择的合理性。     

Architecture for the next generation system management tools

To get more results or greater accuracy, computational scientists execute their applications on distributed computing platforms such as clusters, grids, and clouds. These platforms are different in terms of hardware and software resources as well as locality: some span across multiple sites and multiple administrative domains, whereas others are limited to a single site/domain. As a consequence, in order to scale their applications up, the scientists have to manage technical details for each target platform. From our point of view, this complexity should be hidden from the scientists, who, in most cases, would prefer to focus on their research rather than spending time dealing with platform configuration concerns.In this article, we advocate for a system management framework that aims to automatically set up the whole run-time environment according to the applications’ needs. The main difference with regards to usual approaches is that they generally only focus on the software layer whereas we address both the hardware and the software expectations through a unique system. For each application, scientists describe their requirements through the definition of a virtual platform (VP) and a virtual system environment (VSE). Relying on the VP/VSE definitions, the framework is in charge of (i) the configuration of the physical infrastructure to satisfy the VP requirements, (ii) the set-up of the VP, and (iii) the customization of the execution environment (VSE) upon the former VP. We propose a new formalism that the system can rely upon to successfully perform each of these three steps without burdening the user with the specifics of the configuration for the physical resources, and system management tools. This formalism leverages Goldberg’s theory for recursive virtual machines (Goldberg, 1973 [6]) by introducing new concepts based on system virtualization (identity, partitioning, aggregation) and emulation (simple, abstraction). This enables the definition of complex VP/VSE configurations without making assumptions about the hardware and the software resources. For each requirement, the system executes the corresponding operation with the appropriate management tool.As a proof of concept, we implemented a first prototype that currently interacts with several system management tools (e.g., OSCAR, the Grid’5000 toolkit, and XtreemOS) and that can be easily extended to integrate new resource brokers or cloud systems such as Nimbus, OpenNebula, or Eucalyptus, for instance.     

脉冲防暴水炮运动参数仿真研究

研究增大脉冲防暴水炮的有效射程问题,脉冲防暴水炮是用于处置群体性骚乱事件的大型非致命武器装备,在实战中发挥了重要作用。为改善防暴水炮射程和刺激剂雾化效果,就需要对脉冲防暴水炮的运动参数进行优化设计。通过建立数学模型,然后运用FLUENT流体仿真软件进行运动仿真,最后结合Tecplot后期处理软件的分析,得出了初始压力、初始水量、初始射角等运动参数对水炮射程及雾化效果的影响。在综合各种因素的基础上选择出最佳初始压力和最佳水量,仿真效果比较有效,为设计提供了依据。     

ATN网上的LAN仿真

本文对作为计算机网络未来发展方向的ATM网如何仿真以太网和令牌环的方案作了详细的描述。此方案的优势在于它允许现有的LAN应用在不作任何修改的情况下,便可在ATM网上运行。     

电力电缆载流量模型及其应用研究

研究了电力电缆载流量算法模型的原理、分类方法和特性,并分析了多个实用的模型及其应用;特别介绍了SCR和DCR电缆模型、综合分析方法在电缆系统的设计、在线监测和运行优化方面的应用,并提供了一个应用案例。     

基于六维鼠标控制的飞行器仿真系统研究

本文介绍了在Windows系统平台,C 6．0的MFC基础类库环境下,采用OpenGL技术与串口通信技术实现的飞行器仿真系统的设计思想与程序实现方法。飞行器仿真系统由新型六维鼠标控制,具有六维飞行能力。仿真系统由虚拟飞行器、三维地形和六维鼠标控制系统三部分构成。     

EDA软件MultiSIM2001在电子技术教学中的应用探讨

主要介绍EDA软件Multisim2001的特点及其在电子技术教学中的应用,通过实例表明该软件使用方便,效果直观,能很好的应用于电子技术的教学和科研。     

一个基于图形交互识别的数控仿真集成系统

提高ＮＣ编程自动化程度、柔性、可靠性、集成度一直是相关领域研究人员追求的目标。本文介绍与ＡｕｔｏＣＡＤ和Ｐｒｏｔｅｌ 设计环境无缝接合的数控仿真集成环境ＣＩＭＳＷ 的系统功能及特点,着重介绍基于交互图形特征识别、特征提取、开辟内存缓冲区及Ｗｉｎｄｏｗｓ 编程消息驱动的集成方式     

钻柱纵向振动模型的建立及求解方法

在牙轮钻头与井底岩石互作用模型的基础之上,将钻头在井底作纵向往复运动的位移作为钻柱纵向振动的下端边界条件,在适当简化的条件下,利用弹性杆理论和单元法建立了钻柱在钻井过程中由于钻头与岩石互作用及钻柱的弹性变形而导致钻柱产生纵向振动的动力学模型在给定初始条件和边界条件的情况下,采用数值计算方法求解了钻柱纵振模型。为进一步弄清钻头、钻柱在钻井过程中的实际运动规律和动力学性能,改进钻头、钻柱的设计方法,预防钻头、钻柱早期失效奠定了基础。     

A synopsis of present day practices concerning decision support systems

Selecting a decision support system that fits specific needs, both technically and financially, is a difficult task. The marketplace has been flooded with software bearing the “DSS” label. To provide a clearer picture, the article examines a number of popular DSS definitions and its development. DSS are broken into groups with similar characteristics to examine current software and applications. These groups include Personal Support Systems, DSS and Local Area Networks, DSS and Emulation, Timesharing Systems, Commercial Data Base Systems, and Integrated System. Within each group, current software and practices are reviewed. The potential buyer has the opportunity to compare DSS packages and possible applications. In addition, a list of important questions to ask when choosing DSS Software is included.