An object-oriented multimedia database system for a news-on-demand application

We describe the design of a multimedia database management system for a distributed news-on-demand multimedia information system. News-on-demand is an application that uses broadband network services to deliver news articles to subscribers in the form of multimedia documents. Different news providers insert articles into the database, which are then accessed by users remotely, over a broadband, asynchronous transfer-mode (ATM) network. The particulars of our design are an object-oriented approach and strict adherence to international standards, in particular the Standard Generalized Mark-up Language (SGML) and Hy-Time. The multimedia database system has a visual query facility, which is also described in this paper. The visual query interface provides three major facilities for end users: presentation, navigation, and querying of multimedia news documents. The main focus, however, is the querying of multimedia objects stored in the database.     

Notes on the design of an integrated object-oriented DBMS family

This paper summarizes the design and implementation notes of the CodDdBase system,which is a combinative distributed database management system family based on an integrated object model.CoDdBase is implemented in CLUSTER 86,a general purposed object-oriented programming language designed by the authors.The CoDdBase environment is actually a part of the CLUSTER 86 programming environment,which offers various object-based models,supplies miscellaneous building blocks for constructing different distributed DBMS‘s,and provides integrated programming tools to develop new ways and new models in response to changing application needs.     

Toward a grid-based DBMS

The relational database management system (DBMS) community has been progressing toward using specialized grids. EMC/Acxiom's data grid architecture and MySQL Cluster's grid architecture couple the main memories of PCs with redundancy to implement persistence. In a data grid architecture at its base level is a grid abstract machine, which consists of a collection of typed nodes. The grid abstract machine provides redundant storage in case a node fails. It might also provide interfaces that group nodes into enclaves. This grouping could be based on attributes such as assignment, node type, size, capabilities, physical location, and who owns it. This departs from traditional database implementations, which were tuned to small numbers of processors and in which most algorithms for relational operators and most indices were tuned to disk-block transfers.     

数据库服务器与WWW之间的一种集成设计

本文根据WWW用户和数据库用户各自对数据访问的特点不同,提出了一种将数据库服务器与WWW集成的结构。该集成结构中既提供了基于超文本的导航浏览功能访问数据库系统,又支持用户直接利用数据库系统本身的查询界面,快速查询数据对象。     

数据库服务器与WWW之间的一种集成设计

本文根据WWW用户和数据库用户各自对数据访问的特点不同,提出了一种将数据库服务器与WWW集成的结构。该集成结构中既提供了基于超文本的导航浏览功能访问数据库系统,又支持用户直接利用数据库系统本身的查询界面,快速查询数据对象。     

A Distribution Design Methodology for Object DBMS

The design of distributed databases involves making decisions on the fragmentation and placement of data and programs across the sites of a computer network. The first phase of the distribution design in a top-down approach is the fragmentation phase, which clusters in fragments the information accessed simultaneously by applications. Most distribution design algorithms propose a horizontal or vertical class fragmentation. However, the user has no assistance in the choice between these techniques. In this work we present a detailed methodology for the design of distributed object databases that includes: (i) an analysis phase, to indicate the most adequate fragmentation technique to be applied in each class of the database schema; (ii) a horizontal class fragmentation algorithm, and (iii) a vertical class fragmentation algorithm. Basically, the analysis phase is responsible for driving the choice between the horizontal and the vertical partitioning techniques, or even the combination of both, in order to assist distribution designers in the fragmentation phase of object databases. Experiments using our methodology have resulted in fragmentation schemas offering a high degree of parallelism together with an important reduction of irrelevant data.     

基于LabVIEW可移植数据库管理系统设计研究

针对现有数据库管理系统可移植性差和其实现技术较为复杂的现状,提出了采用VISA结构使系统相对硬件层独立,采用UDL技术解决了连接信息在解决方案的服务器资源之间的可移植性,使系统相对数据库类型独立,通过DCT(DatabaseConnectivityToolkit)工具包实现数据库访问,从而使系统具有较好的可移植性。本文以图书馆管理系统为例,基于LabVIEW实现了上述设计,证实了该设计可行有效。     

Design patterns in object-oriented frameworks

Developing interactive software systems with complex user interfaces has become increasingly common. Given this trend, it is important that new technology be based on flexible architectures that do not require developers to understand all the complexities inherent in a system. Object-oriented frameworks provide an important enabling technology for reusing both the architecture and the functionality of software components. Frameworks typically have a steep learning curve since the user must understand the abstract design of the underlying framework as well as the object collaboration rules or contracts-which are often not apparent in the framework interface-prior to using the framework. The author describes her experience with developing an object-oriented framework for speech recognition applications that use IBM's ViaVoice speech recognition technology. Design patterns help to effectively communicate the internal framework design and reduce dependence on the documentation     

DBMS缓冲区管理器设计的关键技术

OSCAR对象-关系数据库管理系统的缓冲区管理器负责在必要时将页面从磁盘取到主存的软件层。由于主存不可能容纳磁盘上所有的页面,缓冲区管理器需要考虑到页面替换和回写。主要介绍在设计OSCAR缓冲区管理器中使用的关键技术,包括异步I/O、页面读写校验、页面替换策略及动态调整缓冲区物理内存技术。     

面向对象技术在电信网管系统总体设计中的应用

该软件系统的思想是在统一软总线平台下由不同的业务对象模块构成,系统遵循TMN的功能框架构造体系模型,采用面向对象技术、面向组件技术、开放式和分布式系统结构以及3层客户端／服务器体系结构,以实现这些技术在电信网管系统(NMS)中的应用。     

数据库安全功能测试自动化框架设计与实现

传统的top-k查询为顾客返回符合其偏好的产品集合,reverse top-k查询则返回将给定产品作为top-k结果的偏好集合。reverse top-k查询由于能帮助生产者评估产品对顾客的影响,因此在商业分析中具有重要价值。现有的reverse top-k查询假设数据是精确的,许多现实应用中,数据的不确定性广泛存在。将reverse top-k查询扩展到不确定数据上,并给出了基于物化视图的高效查询算法GMV。实验结果表明,GMV算法能够减少需要计算的偏好数量,具有较高的计算效率。     

Design of a large scale multimedia storage server

Large scale multimedia storage servers will be an integral part of the emerging distributed multimedia computing infrastructure. However, given the modest rate of improvements in storage transfer rates, designing servers that meet the demands of multimedia applications is a challenging task that needs significant architectural innovation.Our research project, called Massively-parallel And Real-time Storage (mars) architecture, is aimed at the design and prototype implementation of a large scale multimedia storage server. It uses some of the well-known techniques in parallel I/O, such as data striping and Redundant Arrays of Inexpensive Disks (raid) and an innovative atm based interconnect inside the server to achieve a scalable architecture that transparently connects storage devices to an atm-based broadband network. The atm interconnect within the server uses a custom asic called ATM Port Interconnect Controller (apic) currently being developed as a part of an arpa sponsored gigabit local atm testbed. Our architecture relies on innovative data striping and real-time scheduling to allow a large number of guaranteed concurrent accesses, and uses separation of metadata from real data to achieve a direct flow of the media streams between the storage devices and the network. This paper presents our system architecture; one that is scalable in terms of the number of supported users and the throughput.     

嵌入式实时DBMS进程结构设计

本文首先介绍进程结构设计的方法，并以Informix举例说明，然后基于嵌入式实时的特点。提出了一种动态的多服务器、多线索机制的ERTDBMS的进程结构模型，并给出了如何在RTLinux上实现这个模型。     

Design and implementation of a multimedia CSCW platform

In this paper, a generic four-layer framework for computer supported cooperative work (CSCW) is proposed. With clear separation of functionalities in each layer of the framework, application developers could implement their specific CSCW applications easily. Based on the four-layer framework, the architecture of a general purpose CSCW platform is designed and implemented with the necessary functionalities to help the collaborations among group members. To provide the system with more features and user friendliness, multimedia processing and transmission capabilities for audio and video are incorporated into the platform. Features like application-sharing, group decision support, multimedia mail transmission, etc., are well implemented in the platform. Moreover, an efficient network transport protocol, called VXTP, is designed and implemented to avoid the transmission overhead of conventional TCP. The performance measurements using both VXTP and TCP are given in the paper for comparison. Lastly, compared with other CSCW systems, our design achieves greater flexibility and portability by adopting the generality philosophy in the framework.     

海洋地质调查数据库管理系统设计与实现

介绍海洋地质调查数据库管理系统的设计方法,并在分析该系统的总体结构、功能模块以及数据库特点的基础上,实现该系统的主要功能,同时阐述大圆距离和面积量算、等值线图制作、空间分布分析功能的实现方法,这对于类似的G1S设计与开发具有一定的借鉴和参考价值。     

Design of a Remote Procedure Call system for object-oriented distributed programming

This paper describes the design of an RPC system for building object-oriented distributed software systems. The general requirements for such a system are to provide mechanisms for supporting inheritance, polymorphism, dynamic binding, and modular development in implementing distributed software systems. This paper presents the functionalities of this RPC system to support these general requirements. It also briefly describes the experiences with two previous versions of this system and how they led to the design of the final system. This system was implemented as a part of the programming environment of the Nexus distributed operating system. © 1998 John Wiley & Sons, Ltd.     

基于面向对象的语音编解码软件的设计实现

为了简单正确地应用ITU—T的G．729语音编码标准于应用系统中，遵循G．729B语音编码规范，采用面向对象软件设计方法，开发出一种G．729B语音编解码软件。从用户需求分析出发，介绍了软件的系统设计及实现过程。编解码软件为用户提供了简单的调用接口，并在实践中得以应用。     

嵌入式实时内存数据库恢复子系统的设计

首先分析了嵌入式实时环境的特点,以及需要考虑的问题。然后根据分析,为嵌入式实时环境下运行的内存数据库管理系统设计了一个恢复子系统,包括日志、检验点、备份、恢复处理4个方面,并进行了讨论。     

基于CC标准的DBMS审计模块设计

采用基于标准的安全产品开发方法进行DBMS安全功能增强。首先分析了CC标准中对于审计的功能要求;然后根据数据库管理系统产品的特性提炼出审计方面必须具备的功能;最后给出了一种以特权调用为小心的数据库管理系统审计功能模块的实现方案。