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研究面向对象及其建模技术,利用面向对象的方法对流程工业优化调度系统的STN图进行建模,有效地提高程序的可靠性、可维护性和可扩展性。 相似文献
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UML是面向对象软件开发中的重要技术。使用UML进行系统建模,就是使用面向对象的方法来分析系统,以此建立面向对象的系统模型。本文针对房地产企业的特点,以房地产测绘信息管理系统为实例,阐述了如何使用UML中的用例图、顺序图和合作图来进行系统分析,以此帮助系统开发人员进行详细需求分析,并能更清楚地了解系统功能和系统流程的分析。 相似文献
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许爱军 《计算机测量与控制》2016,24(4):210-213, 218
为集中展示校园风貌和文化氛围,基于Creator和Vega平台实现了自动导航寻径的虚拟校园漫游系统;结合校园建筑特点,引入面向对象思想并应用有向无环树状图组织场景数据,实现了对虚拟场景的层次化管理;在建模阶段,利用不同精度的纹理贴图生成不同精度的模型,给出了支持LOD的快速建模方法;在漫游导航中,通过鼠标拾取实时显示虚拟物体的属性信息,运用方向优先的Dijkstra算法查找最短路径并实现漫游导航功能;在普通PC上测试,无论是单个模型的渲染效率还是系统的整体性能,场景的逼真度和浏览的顺畅性都较为理想,体现出人机工程顺畅和自然的特征。 相似文献
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面向对象建模是一种运用对象、类、继承、封装、聚合、消息传送、多态等概念来构造系统的软件开发方法.UML是一种面向对象的统一建模语言.基于UML的三种面向对象模型,运用UML建模机制为教材管理系统建模,给出相应的域类图、活动图、交互图和用例模型. 相似文献
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在仿真建模中,为了使建模工具简单易用、仿真运行高效,建立了三层仿真元模型体系结构,并在流程定义分析的基础上,结合扩展有向图建模方法,针对模型层研究了离散事件驱动的流程建模方法。基于该流程建模方法及XML文档形式化描述及数据传递技术,采用面向对象的设计方法,开发了适用于离散事件驱动的流程建模系统。该系统提供了简单的可视化流程建模工具,简化了建模流程,易于对模型的理解与交流。 相似文献
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UML是一种定义良好、易于表达、功能强大且普遍适用的统一建模语言,是面向对象建模领域的工业标准。介绍了UML统一建模语言及其建模工具Rational Rose,以考试信息系统为研究对象,分析了其需求和流程,并利用UML的用例图和顺序图及其建模工具Rational Rose对考试信息系统进行了建模。 相似文献
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基于UML的系统需求分析 总被引:1,自引:0,他引:1
UML(Unified Modelling Language)是面向对象方法建模的语言标准工具,在系统建模过程中应用很广泛,在UML技术指导下,针对软件开发过程中的需求分析阶段,提出了一种结构清晰的功能需求分析模型,在系统用例图的基础上,建立类图和时序图,从静态和动态不同侧面表达系统模型,迭代的建模过程保证了模型的一致性,一个实例详细描述了系统功能需求分析建模的过程. 相似文献
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基于UML的面向对象建模方法研究 总被引:5,自引:0,他引:5
针对面向对象的建模方法,介绍了应用UML建模的具体方法和流程,其中列举了UML建模的实例,详细阐述了用例图、类图、顺序图的运用。 相似文献
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Space Division for Ray Tracing in CSG 总被引:3,自引:0,他引:3
A system of Constructive Solid Geometry (CSG) enables an engineering designer to compose threedimensional shapes by combining simpler ones. Definitions of such objects are represented by tree structures or directed acyclic graphs. Most existing systems convert this representation to a more conventional boundary representation of the solids in order to render pictures from the model. More recently, a number of systems have been described that render the pictures directly from the CSG structure. We describe such a system. We render a scene by ray tracing from a directed acyclic graph. This process is made efficient for large models by using an adaptive method of space division to reduce the number of intersection calculations needed. 相似文献
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委托是常见的一种安全策略形式,委托可以用带标识的有向图对其严格地形式化建模,称为委托图。给出了委托图的定义,存储,委托图中实现委托的算法,委托图无环性判定算法,并进行了分析,讨论了委托图的性质。 相似文献
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Oded Shmueli 《Information Processing Letters》1983,17(4):185-188
This paper presents algorithms for maintaining a directed acyclic graph in a dynamically changing environment. In such an environment, nodes and edges are occasionally added and deleted. The underlying idea is to perform a depth first search after each edge addition. Heuristics are presented to make fewer and relatively short searches.The problem of maintaining a directed acyclic graph arises naturally in situations involving resource contention. In operating and database systems, one often maintains a directed ‘wait for’ graph. A cycle in such a graph indicates deadlock. Thus, the algorithm presented here is attractive for centralized continuous deadlock detection. 相似文献
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制造系统虚拟仿真原型工具的研究 总被引:5,自引:1,他引:5
通过对制造系统的分析,基于将“面向对象的分析方法、三维几何模型和仿真机制”统一起来的有向图仿真建模机制,提出虚拟仿真工具的模块化体系结构,开发了面向制造系统的专用虚拟仿真工具,并介绍该虚拟仿真原型工具的总体结构及其主要功能模块。 相似文献
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This paper investigates the issue of building software in the Internet environment, where local area network (LAN) based
systems are interconnected by links with different bandwidth and do not share file systems. The software is modeled as a directed
acyclic graph. Each node in the graph represents a logical step in processing the software while the edges describe the order
of execution. The problem is to construct the software at a particular LAN with minimum Internet communication cost. An optimal
polynomial algorithm, SOFTCON, with time complexity is presented, where and are the number of nodes and edges in the graph describing the software respectively, is the number of LANs in the Internet environment, and is the time complexity of the network flow algorithm on the flow network with nodes and edges transformed from the directed acyclic graph of the software.
Received: 6 December 1995 / 1 May 1996 相似文献
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Kumar Jain K. Rajaraman V. 《Parallel and Distributed Systems, IEEE Transactions on》1994,5(8):879-886
The lower and upper bounds on the minimum time needed to process a given directed acyclic task graph for a given number of processors are derived. It is proved that the proposed lower bound on time is not only sharper than the previously known values but also easier to calculate. The upper bound on time, which is useful in determining the worst case behavior of a given task graph, is presented. The lower and upper bounds on the minimum number of processors required to process a given task graph in the minimum possible time are also derived. It is seen with a number of randomly generated dense task graphs that the lower and upper bounds we derive are equal, thus giving the optimal time for scheduling directed acyclic task graphs on a given set of processors 相似文献