等高线测绘过程中常见技术问题的解决方法

针对等高线测绘中经常出现的一些技术问题,以南方CASS软件为例对等高线的外业测量到内业绘制方法作了详细介绍,主要包括地貌特征点采集、高程点预处理、绘制地性线、提取高程点数据文件、DTM建立与修改、绘制等高线、等高线后处理工作、等高线的滤波与拟合等内容。     

Competitive Strategy Analysis in the International Document Delivery Services: A View from Taiwan

ABSTRACT

The authors examine international document delivery services, both from libraries and information brokers, between Taiwan and other countries. After examining the current state of document delivery, uses business techniques, including SWOT Analysis (Strength and Weakness Evaluation), to suggest ways to improve and increase the volume of materials sent from Taiwan to the rest of the world.     

Clustering tagged documents with labeled and unlabeled documents

This study employs our proposed semi-supervised clustering method called Constrained-PLSA to cluster tagged documents with a small amount of labeled documents and uses two data sets for system performance evaluations. The first data set is a document set whose boundaries among the clusters are not clear; while the second one has clear boundaries among clusters. This study employs abstracts of papers and the tags annotated by users to cluster documents. Four combinations of tags and words are used for feature representations. The experimental results indicate that almost all of the methods can benefit from tags. However, unsupervised learning methods fail to function properly in the data set with noisy information, but Constrained-PLSA functions properly. In many real applications, background knowledge is ready, making it appropriate to employ background knowledge in the clustering process to make the learning more fast and effective.     

航空维修文献数据库的设计与实现

从 L otus Notes群件系统着手 ,简要介绍了 Domino设计元素 ,对航空维修文献数据库的设计与实现进行了较详细的论述     

Threshold Setting and Performance Optimization in Adaptive Filtering

An experimental adaptive filtering system, built on the Okapi search engine, is described. In addition to the regular text retrieval functions, the system requires a complex set of procedures for setting score thresholds and adapting them following feedback. These procedures need to be closely related to the evaluation measures to be used. A mixture of quantitative methods relating a threshold to the number of documents expected to be retrieved in a time period, and qualitative methods relating to the probability of relevance, is defined. Experiments under the TREC-9 Adaptive Filtering Track rules are reported. The system is seen to perform reasonably well in comparison with other systems at TREC. Some of the variables that may affect performance are investigated.     

我国少数民族文字文献的书目控制

我国少数民族文字文献书目工作起始于公元 9世纪中叶对藏文献的编目。新中国成立后 ,少数民族文字文献书目工作经过了初步发展和迅速发展时期。目前 ,少数民族文字信息处理工程已全面启动 ,少数民族语文主题词表正在研制中 ,著录标准化正在实现 ,书目管理系统开始运行 ,工作正在向现代化迈进。参考文献 7。     

Introduction to the Special Issue: Overview of the TREC Routing and Filtering Tasks

This paper introduces the special issue, and reviews the routing and filtering tasks as defined and evaluated at TREC. The tasks attempt to simulate a specific service situation: the system is assumed to process an incoming stream of documents against profiles of user interest, strictly in the time order in which they arrive, and immediately refer any matching document to the user. In the adaptive filtering version of the task, the user is assumed to provide a relevance judgement instantly. The rationale for the task definitions and the evaluation measures used is discussed.     

网络信息过滤的方法与相关技术研究*

随着因特网的发展出现了所谓的“信息过载”问题，为了向用户提供个性化、实用性的信息，信息过滤技术应运而生。结合国内外已有的研究成果，本文从用户的信息需求与表示、文档的表示技术、匹配技术、信息反馈技术等四个方面探讨网络信息过滤的方法与技术以及存在的问题。     

ADO技术在文献信息检索中的应用

结合馆藏文献检索系统的开发，介绍了利用ADO技术在Web页面上检索文献信息的方法，对其工作原理、ODBC数据源指定、文献检索的方法与设计等作了较详细的阐述，并分析了这种技术的适用范围。