Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Zbroker: A Query Routing Broker For Z39.50 Databases, Yong Lin, Jian Xu, Ee Peng Lim, Wee-Keong Ng
Zbroker: A Query Routing Broker For Z39.50 Databases, Yong Lin, Jian Xu, Ee Peng Lim, Wee-Keong Ng
Research Collection School Of Computing and Information Systems
A query routing broker is a software agent that determines from a large set of accessing information sources the ones most relevant to a user's information need. As the number of information sources on the Internet increases dramatically, future users will have to rely on query routing brokers to decide a small number of information sources to query without incurring too much query processing overheads. In this paper, we describe a query routing broker known as ZBroker developed for bibliographic database servers that support the Z39.50 protocol. ZBroker samples the content of each bibliographic database by using training queries and …
Wedagen: A Synthetic Web Database Generator, Pallavi Priyardarshini, Fengqiong Qin, Ee Peng Lim, Wee-Keong Ng
Wedagen: A Synthetic Web Database Generator, Pallavi Priyardarshini, Fengqiong Qin, Ee Peng Lim, Wee-Keong Ng
Research Collection School Of Computing and Information Systems
At the Centre for Advanced Information Systems (CAIS), a Web warehousing system is being developed to store and manipulate Web information. The system named WHOWEDA (WareHouse Of WEb DAta) stores extracted Web information as Web tables and provides several Web operators, eg. Web join, Web select, global coupling, etc., to manipulate Web tables. During the implementation of WHOWEDA, it is necessary to perform systematic testing on the system and to evaluate its system performance. While it is possible for WHOWEDA to be tested or evaluated using actual Web pages downloaded from WWW, the amount of time required for such testing …
Locating Web Information Using Web Checkpoints, Aik Kee Luah, Wee-Keong Ng, Ee Peng Lim, Wee Peng Lee, Yinyan Cao
Locating Web Information Using Web Checkpoints, Aik Kee Luah, Wee-Keong Ng, Ee Peng Lim, Wee Peng Lee, Yinyan Cao
Research Collection School Of Computing and Information Systems
Conventional search engines locate information by letting users establish a single web checkpoint1. By specifying one or more keywords, users direct search engines to return a set of documents that contain those keywords. From the documents (links) returned by search engines, user proceed to further probe the WWW from there. Hence, these initial set of documents (contingent upon the occurrence of keyword(s)) serve as a web checkpoint. Generally, these links are numerous and may not result in much fruitful searches. By establishing multiple web checkpoints, a richer and controllable search procedure can be constructed to obtain more relevant Web information. …
Non-Repudiation In An Agent-Based E-Commerce System, Chin Chuan Liew, Wee-Keong Ng, Ee Peng Lim, Beng Suang Tan, Kok-Leong Ong
Non-Repudiation In An Agent-Based E-Commerce System, Chin Chuan Liew, Wee-Keong Ng, Ee Peng Lim, Beng Suang Tan, Kok-Leong Ong
Research Collection School Of Computing and Information Systems
Abecos is an agent-based e-commerce system under development at the Nanyang Technological University. A key factor in making this system usable in practice is strict security controls. One aspect of security is the provision of non-repudiation services. As protocols for non-repudiation have focused on -message non-repudiation, its adaptation to afford non-repudiation in a communication session for two agents in Abecos is inefficient. In this work, we investigate and propose a protocol for enforcing non-repudiation in a session. The protocol is believed to be applicable in any e-commerce system; agent- or not agent-based.
Cluster-Based Database Selection Techniques For Routing Bibliographic Queries, Jian Xu, Ee Peng Lim, Wee-Keong Ng
Cluster-Based Database Selection Techniques For Routing Bibliographic Queries, Jian Xu, Ee Peng Lim, Wee-Keong Ng
Research Collection School Of Computing and Information Systems
In this paper, we focus on the database selection problem in the context of a global digital library consisting of a large number of online bibliographic servers. Each server hosts a bibliographic database that contains bibliographic records each of which consists of text values for a number of pre-defined bibliographic attributes such as title, author, call number, subject, etc.. Each bibliographic database supports user queries on the bibliographic attributes. Since bibliographic records are relatively small in size, we only consider bibliographic databases that support boolean queries on the bibliographic attributes, and the query results are not ranked. While focusing on …
Resource Scheduling In A High-Performance Multimedia Server, Hwee Hwa Pang, Bobby Jose, M. S. Krishnan
Resource Scheduling In A High-Performance Multimedia Server, Hwee Hwa Pang, Bobby Jose, M. S. Krishnan
Research Collection School Of Computing and Information Systems
Supporting continuous media data-such as video and audio-imposes stringent demands on the retrieval performance of a multimedia server. In this paper, we propose and evaluate a set of data placement and retrieval algorithms to exploit the full capacity of the disks in a multimedia server. The data placement algorithm declusters every object over all of the disks in the server-using a time-based declustering unit-with the aim of balancing the disk load. As for runtime retrieval, the quintessence of the algorithm is to give each disk advance notification of the blocks that have to be fetched in the impending time periods, …
Harp: A Distributed Query System For Legacy Public Libraries And Structured Databases, Ee Peng Lim, Ying Lu
Harp: A Distributed Query System For Legacy Public Libraries And Structured Databases, Ee Peng Lim, Ying Lu
Research Collection School Of Computing and Information Systems
The main purpose of a digital library is to facilitate users easy access to enormous amount of globally networked information. Typically, this information includes preexisting public library catalog data, digitized document collections, and other databases. In this article, we describe the distributed query system of a digital library prototype system known as HARP. In the HARP project, we have designed and implemented a distributed query processor and its query front-end to support integrated queries to preexisting public library catalogs and structured databases. This article describes our experiences in the design of an extended Sequel (SQL) query language known as HarpSQL. …