Management of multidimensional discrete data

Spatial database management involves two main categories of data: vector and raster data. The former has received a lot of in-depth investigation; the latter still lacks a sound framework. Current DBMSs either regard raster data as pure byte sequences where the DBMS has no knowledge about the underlying semantics, or they do not complement array structures with storage mechanisms suitable for huge arrays, or they are designed as specialized systems with sophisticated imaging functionality, but no general database capabilities (e.g., a query language). Many types of array data will require database support in the future, notably 2-D images, audio data and general signal-time series (1-D), animations (3-D), static or time-variant voxel fields (3-D and 4-D), and the ISO/IEC PIKS (Programmer's Imaging Kernel System) BasicImage type (5-D). In this article, we propose a comprehensive support ofmultidimensional discrete data (MDD) in databases, including operations on arrays of arbitrary size over arbitrary data types. A set of requirements is developed, a small set of language constructs is proposed (based on a formal algebraic semantics), and a novel MDD architecture is outlined to provide the basis for efficient MDD query evaluation.     

The aditi deductive database system

Deductive databases generalize relational databases by providing support for recursive views and non-atomic data. Aditi is a deductive system based on the client-server model; it is inherently multi-user and capable of exploiting parallelism on shared-memory multiprocessors. The back-end uses relational technology for efficiency in the management of disk-based data and uses optimization algorithms especially developed for the bottom-up evaluation of logical queries involving recursion. The front-end interacts with the user in a logical language that has more expressive power than relational query languages. We present the structure of Aditi, discuss its components in some detail, and present performance figures.     

A load-balanced parallel sorting algorithm for shared-nothing architectures

With the popularity of parallel database machines based on the shared-nothing architecture, it has become important to find external sorting algorithms which lead to a load-balanced computation, i.e., balanced execution, communication and output. If during the course of the sorting algorithm each processor is equally loaded, parallelism is fully exploited. Similarly, balanced communication will not congest the network traffic. Since sorting can be used to support a number of other relational operations (joins, duplicate elimination, building indexes etc.) data skew produced by sorting can further lead to execution skew at later stages of these operations. In this paper we present a load-balanced parallel sorting algorithm for shared-nothing architectures. It is a multiple-input multiple-output algorithm with four stages, based on a generalization of Batcher's odd-even merge. At each stage then keys are evenly distributed among thep processors (i.e., there is no final sequential merge phase) and the distribution of keys between stages ensures against network congestion. There is no assumption made on the key distribution and the algorithm performs equally well in the presence of duplicate keys. Hence our approach always guarantees its performance, as long asn is greater thanp ³, which is the case of interest for sorting large relations. In addition, processors can be added incrementally. Recommended by: Patrick Valduriez     

对象数据库标准—介绍与分析

一、引言 随着应用领域的扩大和对象数据库的纷纷涌现,对象数据库的用户和厂商都强需要一个对象数据库标准.为此,国际标准化组织(ISO)和美国国家标准局(ANSI)以及一些联合体了大量和对象     

浅谈石油勘探开发信息系统与石油地质工作站

随着计算机工业的发展,高性能图形工作站、多媒体计算机、超文本系统、卫星通讯等先进技术进入了实用阶段,尽快建立海洋石油勘探开发信息系统及石油地质工作站已成为可能。论述了海洋石油勘探开发信息系统和石油地质工作站的研制思路,提出了海洋石油勘探开发信息系统和石油地质信息系统的结构的初步方案。     

单相电机自动测试系统

简述了微机控制的单相电机自动测试的组成，功能及其工作过程，介绍了系统的特点，着重讨论了动态测试，数据通讯和数据库技术在电机测试中的应用。     

A pictorial index mechanism for model-based matching

We are currently developing unified query processing strategies for image databases. To perform this task, model-based representations of images by content are being used, as well as a hierarchical generalization of a relatively new object-recognition technique called data-driven indexed hypotheses. As the name implies, it is index-based, from which its efficiency derives. Earlier approaches to data-driven model-based object recognition techniques were not capable of handling complex image data containing overlapping, partially visible, and touching objects due to the limitations of the features used for building models. Recently, a few data-driven techniques capable of handling complex image data have been proposed. In these techniques, as in traditional databases, iconic index structures are employed to store the image and shape representation in such a way that searching for a given shape or image feature can be conducted efficiently. Some of these techniques handle the insertion and deletion of shapes and/or image representations very efficiently and with very little influence on the overall system performance. However, the main disadvantage of all previous data-driven implementations is that they are main memory based. In the present paper, we describe a secondary memory implementation of data-driven indexed hypotheses along with some performance studies we have conducted.     

数据录入约束与导航器

信息软件使用的方便性、易用性、安全性和稳定性在很大程度上取决于数据录入方式的优劣。分析了数据录入的约束规则，探讨了录入导航原理，并介绍了一种已在开目管理软件中普遍采用的数据录入导航器组件。     

岩样自然伽玛能谱的数据库管理系统

本文阐述了岩样自然伽玛能谱数据库管理系统的功能、结构、特点以及它在研究自然伽玛能谱与岩性参数间关系中的应用，为自然伽玛能谱测井的资料解释奠定了理论基础。