公路路线CAD系统的数据管理方法

介绍公路路线CAD系统数据管理方法的类型和特点,提出采用Excel文档这一新的数据管理方法,并分析该方法的特点。采用VB编程和ActiveX技术,实现在公路路线CAD系统主程序中控制与操作Excel文档的功能。     

面向定制化牙科产品的协同设计系统的研究

为了快速设计和制造定制化牙科产品,结合牙科产品的特点,分析了定制化牙科产品协同设计系统中各组织间的协同作用、产品协同设计过程以及协同设计系统的结构;以定制化托槽为例,研究了结合托槽设计及选区激光熔化快速成型的协同设计系统的产品设计制造流程,运用统一建模语言建立了定制化托槽的协同设计过程.实例表明,采用该系统,牙科产品开发商与牙科医生协作实现快速设计并制造定制化产品.     

桥梁协同设计系统数据动态管理模式

针对桥梁协同设计中群体间的信息共享需求,从协同设计的数据动态管理模式角度对信息共享的理论与方法进行了研究,分析了结构设计群体与抗震设计群体之间的协同工作过程,完成了含原子数据、组合数据、构件、有限元模型、子结构、结构等设计信息的数据表达模型.研究了含数据变换和动态激励的数据管理方法,满足了协同工作群体间信息共享的需求.以某连续梁桥为例,模拟分析结构设计群体与抗震设计群体间的协同工作过程,对动态管理模式的可实施性进行了验证.     

城市道路交通事故信息系统空间数据库设计

有效的空间数据库存储结构是实现以集成型数据管理方式为基础的应用系统的关键问题之一.它将决定整个系统的功能和效率.按照为用户的数据视图建模、定义实体及其关系、选择地理表达方式、匹配到Geodatabase元素、组织Geodatabase结构和制定数据库存储方案等六个步骤对城市道路交通事故信息系统之空间数据库进行了规范化设计.设计所得的空间数据库接近于其逻辑数据模型.分析结果表明,该设计方法有利于优化实现城市道路交通事故信息系统的系统功能.     

OA系统与档案管理系统数据交换的研究与实现

Lotus Domino是当今办公自动化系统的主流开发平台之一,苏州大学的OA系统正是基于这个平台开发的。Domino自带一个非关系型数据库——文档型数据库,而苏州大学的档案管理系统的数据存储在SQL Server——关系型数据库中。因此要实现OA系统与档案管理系统的数据交换,必须要解决Domino和关系数据库的数据交换问题。本文利用ODBC实现Domino和关系数据库的互操作。     

面向动态模糊数据的关系数据库系统的研究

为使关系数据库系统具备处理动态模糊数据的能力,将动态模糊理论和关系数据库理论相结合,通过分析面向动态模糊数据的关系数据库系统的功能,构造了该数据库的系统结构,探讨了实现该数据库的方法,对面向动态模糊数据的关系数据库系统做了初步的研究。     

An ontology-based support for product conceptual design

The research presented in this paper is a follow-up of our prior work involving the development of a graphical modeling tool to support designers at the conceptual design stage. To close the loop for supporting designers in generating design concepts flexibly, fast, and easily, an ontology-based approach for knowledge management that works along with the graphical modeling tool is discussed. Ontology and databases for the tool are developed to promote the systematic capture of design knowledge and efficient reuse of the design knowledge selection. In order to locate the proper information and query the data from the databases, the relationship between the ontology and databases, the data analysis process, ontology enrichment, and the ontology-based query engine are built to offer users multiple design results according to users’ requirements. A tire design example is presented to demonstrate the proposed approach. The ontology-based method described in this paper can help retrieve and save the complex relations, support the reasoning, integrate heterogeneous data resources and offer users more accurate, proper and comprehensive data.     

XStorM: A Scalable Storage Mapping Scheme for XML Data

With the increasing ubiquity of XML, an eXtensible Markup Language, the industry is racing to provide XML infrastructure for e–commerce, information interchange, effective query of diverse sources and yet more integration of diverse data. It is anticipated that large volumes of XML data will be created manually from HTML documents or generated using some WWW tools and electronic data interchange (EDI). In this paper, we examine how large amounts of XML data can be stored in a relational database. Our scheme considers the unique irregular features of XML, including missing elements or multiple occurrences of the same element, and elements which may have atomic values in some data items and structured values in others. A detailed experimental study demonstrates good query performance, effective space utilization and scalability.     

XML-based data processing in network supported collaborative design

In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language(XML)based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data(STEP)with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language(SQL) queries. Finally, the structure of data processing system based on XML is presented.     

大数据时代数据管理方式的研究

各种各样网络的兴起和发展,半结构化及非结构化数据成几何倍数增长,数据规模和数据种类正以前所未有的速度增长,大数据时代已经来临。如何更好地管理和利用大数据已经成为普遍关注的话题。简要分析了数据库技术的发展历程,阐述了大数据时代数据管理方式,并对大数据时代数据管理方式作出了展望。     

反应堆仪控系统工程管理数据库的设计与开发

为更加科学管理10 MW固态燃料钍基熔盐堆核能系统仪控系统的相关数据及文件,提出反应堆仪控系统工程管理数据库的设计方案。根据反应堆数字化仪控系统的软硬件信息紧密相关的特点,对工程数据进行分析与分类,设计仪控系统工程管理数据库的数据结构,使用MySql软件进行数据管理。在此基础上,应用B/S结构软件开发技术实现数据管理平台的功能开发。实践验证了该数据库系统提高了工程管理效率,为今后反应堆的数据管理和科学使用奠定了基础。     

一个适用于IC－CAD系统的设计库管理系统及其改进

当前，开发以数据库为核心的集成化ＣＡＤ系统已迫在眉睫。本文简单回顾了工程数据库的发展背景，然后介绍一个适用于ＩＣ－ＣＡＤ系统的设计库管理系统ＩＣＤＭＳ，着重讨论了对该系统的一些改进。经测试，改进以后的ＩＣＤＭＳ的功能有明显的增强和改善。     

Database design practices for inverted files

Database research literature has proposed many procedures, both manual and automated, for database design; selection of secondary indexes for inverted file type database management systems (DBMS) has been repeatedly addressed. The empirical study reported here indicates that practical inverted file design has been relatively unaffected by this research.This paper characterizes the actual database design process used at inverted file DBMS installations along such dimension as: types of secondary keys constructed, the individuals who make index design decisions, the decisions that are changed (and when) after the initial database implementation, the factors that are considered in indexing decisions, and the literature which is used in the process. The study shows that key selection (as one example of a design decision) is addressed by ad hoc procedures and well conceived procedures are not used. Further, the results indicate that database design is dominated by users and systems analysts, indexes are frequently changed and a wide range of database performance and convenience factors are influential in practice. The paper concludes with some recommendations for database design support tools.     

基于PLC的铁路枕簧智能分选系统的开发

该系统采用了当今先进的集成控制——主从分布式控制系统,由欧姆龙公司的PLC完成对枕簧自动检测、分检系统的控制。本文介绍了枕簧检测、喷漆、烘干、分拣控制系统的组成、工作原理、控制方式及程序设计思想。实际应用证明:该系统提高了检测精度、降低劳动强度,保证了列车安全运行。     

一个开放可扩展的SDAI实现系统

STEP标准数据存取界面－SDAI为应用程序提供了独立于数据存储的STEP数据访问界面，SDAI允许访问不同的数据存储系统，有不同的实现语言联编方式，如果对每一种实用语言和数据存储系统单独实现SDAI，其工作量将是巨大的，该文选择系数据库作为SDAI数据存储系统，C语言作为实现语言，实现系统独立于不同的关系数据库系统，并且为不同语言的联编提供了一个统一的开发平台，提高了系统的开放性和可扩展性，为STEP在企业信息集成中的应用提供了核心操作，STEP建模语言EXPRESS，关系数据库，SDAI实现语言在模式表示上的不匹配是系统实现要解决的主要问题，该文从数据字典，STEP数据的字储与访问等方面阐明了系统实现时没模式之间的匹配过程。     

An intelligent system for automatic layout routing in aerospace design

This paper discusses the development of an intelligent routing system for automating design of electrical wiring harnesses and pipes in aircraft. The system employs knowledge based engineering (KBE) methods and technologies for capturing and implementing rules and engineering knowledge relating to the routing process. The system reads a mesh of three dimensional structure and obstacles falling within a given search space and connects source and target terminals satisfying a knowledge base of design rules and best practices. Routed paths are output as computer aided design (CAD) readable geometry, and a finite element (FE) mesh consisting of geometry, routed paths and a knowledge layer providing detail of the rules and knowledge implemented in the process. Use of this intelligent routing system provides structure to the routing design process and has potential to deliver significant savings in time and cost.     

支持并行设计的产品数据管理

产品数据管理是基于数据库,分布计算和网络通讯等技术发展起来的新型工程数据管理技术,是有效管理和控制所有与产品有关的信息的并行设计框架,本文研究了支持大型电子设备并行设计的产品数据管理系统ＹＣ－Ｂｒｉｄｇｅ的开放式体系结构,并介绍了它的主要功能,实现方法及技术特点。     

Using an entity model to drive physical database design

Logical relational database design, because of its implementation-independent nature, has been successfully formalized. Physical relational database design, because of its implementation-dependent nature, has remained largely unformalized and disconnected, not only from logical design but also from conceptual database design. The paper suggests a model for the physical design process that has proven useful in a number of practical development projects. The model demonstrates that a seamless join between conceptual, logical and physical design work is feasible. It illustrates how the process of annotating a conceptual model with physical detail provides a useful framework for driving the process of physical relational database design.     

PIST: An Efficient and Practical Indexing Technique for Historical Spatio-Temporal Point Data

Despite pressing need, current relational database management systems (RDBMS) support for spatio-temporal data is limited and inadequate, and most existing spatio-temporal indices cannot be readily integrated into existing RDBMSs. This paper proposes a practical index for spatio-temporal (PIST) data, an indexing technique, rather than a new indexing structure, for historical spatio-temporal data points that can be fully integrated within existing RDBMSs. PIST separates the spatial and temporal components of the data. For the spatial component, we develop a formal cost model and a partitioning strategy that leads to an optimal space partitioning for uniformly distributed data and an efficient heuristic partitioning for arbitrary data distributions. For the temporal component of the data a B^?+?-tree is used. We show that this layer’s performance can be maximized if an optimal maximal temporal range is enforced, and we present a procedure to determine such an optimal value. Being fully mapped onto a RDBMS, desirable and important properties, such as concurrency control, are immediately inherited by PIST. Using ORACLE as our implementation platform we perform extensive experiments with both real and synthetic datasets comparing its performance against other RDBMS-based options, as well as the MV3R-tree. PIST outperforms the former by at least one order of magnitude, and is competitive or better with respect to the latter, with the unarguable advantage that it can readily used on top of virtually any existing RDBMS.