Browsing by Author "Chuang, SL"

Now showing 1 - 3 of 3

Exploration of Web users' search interests through automatic subject categorization of query terms
(2001)
Pu, HT
;
Chuang, SL
;
Yang, C
;
交大名義發表
;
National Chiao Tung University
Web query term logs from Internet search engines provide an unobtrusive source for understanding users' search interests. To make the subject categorization of Web query terms more efficient and adaptive, an automatic or computer-aided mechanism is needed. The purpose of this paper is therefore to propose a mechanism that carefully integrates human and machine efforts to explore Web users' search interests. The approach is designed to consist of a four-step process including the extraction of core terms, construction of subject taxonomy, automatic subject categorization of query terms, and observation of users' search interests. Some experiments have been conducted, and the preliminary results show that it is possible to categorize query terms into a pre-defined subject taxonomy which helps to explore users' search interests by online monitoring the distribution of subject categories and the composed query terms in real time. The research findings are proved valuable for enhancing Web IR (Information Retrieval) systems and Web content organization.
Maximum entropy analysis to the N policy M/G/1 queueing system with a removable server
(2002-12-01)
Wang, KH
;
Chuang, SL
;
Pearn, WL
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
We study a single removable server in an M/G/1 queueing system operating under the N policy in steady-state. The server may be turned on at arrival epochs or off at departure epochs. Using the maximum entropy principle with several well-known constraint, we develop the approximate formulae for the probability distributions of the number of customers and the expected waiting time in the queue. We perform a comparative analysis between the approximate results with exact analytic results for three different service time distributions, exponential, 2-stage Erlang, and 2-stage hyper-exponential, The maximum entropy approximation approach is accurate enough for practical purposes. We demonstrate, through the maximum entropy principle results, that the N policy M/G/1 queueing system is sufficiently robust to the variations of service time distribution functions. (C) 2002 Elsevier Science Inc. All rights reserved.
Subject categorization of query terms for exploring Web users' search interests
(2002-06-01)
Pu, HT
;
Chuang, SL
;
Yang, C
;
資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
Subject content analysis of Web query terms is essential to understand Web searching interests. Such analysis includes exploring search topics and observing changes in their frequency distributions with time. To provide a basis for in-depth analysis of users' search interests on a larger scale, this article presents a query categorization approach to automatically classifying Web query terms into broad subject categories. Because a query is short in length and simple in structure, its intended subject(s) of search is difficult to judge. Our approach, therefore, combines the search processes of real-world search engines to obtain highly ranked Web documents based on each unknown query term. These documents are used to extract cooccurring terms and to create a feature set. An effective ranking function has also been developed to find the most appropriate categories. Three search engine logs in Taiwan were collected and tested. They contained over 5 million queries from different periods of time. The achieved performance is quite encouraging compared with that of human categorization. The experimental results demonstrate that the approach is efficient in dealing with large numbers of queries and adaptable to the dynamic Web environment. Through good integration of human and machine efforts, the frequency distributions of subject categories in response to changes in users' search interests can be systematically observed in real time. The approach has also shown potential for use in various information retrieval applications, and provides a basis for further Web searching studies.