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Displaying 1-50 out of 147 total
IR-Tree: An Efficient Index for Geographic Document Search
Found in: IEEE Transactions on Knowledge and Data Engineering
By Zhisheng Li, Ken C.K. Lee, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee, Xufa Wang
Issue Date:April 2011
pp. 585-599
Given a geographic query that is composed of query keywords and a location, a geographic search engine retrieves documents that are the most textually and spatially relevant to the query keywords and the location, respectively, and ranks the retrieved docu...
 
Personalized Feed Recommendation Service for Social Networks
Found in: Social Computing / IEEE International Conference on Privacy, Security, Risk and Trust, 2010 IEEE International Conference on
By Huajing Li, Yuan Tian, Wang-Chien Lee, C. Lee Giles, Meng-Chang Chen
Issue Date:August 2010
pp. 96-103
Social network systems (SNSs) such as Facebook and Twitter have recently attracted millions of users by providing social network based services to support easy message posting, information sharing and inter-friend communication. With the rapid growth of so...
 
Search Continuous Nearest Neighbors on the Air
Found in: Mobile and Ubiquitous Systems, Annual International Conference on
By Baihua Zheng, Wang-Chien Lee, Dik Lun Lee
Issue Date:August 2004
pp. 236-245
A continuous nearest neighbor (CNN) search retrieves the nearest neighbors corresponding to every point in a given query line segment. It is important for location-based services such as vehicular navigation tools and tourist guides. It is infeasible to an...
 
Transitive Nearest Neighbor Search in Mobile Environments
Found in: Sensor Networks, Ubiquitous, and Trustworthy Computing, International Conference on
By Baihua Zheng, Ken C.K. Lee, Wang-Chien Lee
Issue Date:June 2006
pp. 14-21
Given a query point p, typically the position of a current client, and two datasets S and R, a transitive nearest neighbor (TNN) search returns a pair of objects (s, r) E? S x R such that the total distance from p to s and then to r, i.e., dis(p, s) + dis(...
 
Monitoring Top-k Query inWireless Sensor Networks
Found in: Data Engineering, International Conference on
By Minji Wu, Jianliang Xu, Xueyan Tang, Wang-Chien Lee
Issue Date:April 2006
pp. 143
Top-k monitoring is important to many wireless sensor applications. This paper exploits the semantics of top-k query and proposes a novel energy-efficient monitoring approach, called FILA. The basic idea is to install a filter at each sensor node to suppre...
 
DSI: A Fully Distributed Spatial Index for Location-Based Wireless Broadcast Services
Found in: Distributed Computing Systems, International Conference on
By Wang-Chien Lee, Baihua Zheng
Issue Date:June 2005
pp. 349-358
Recent announcement of the MSN Direct Service has demonstrated the feasibility and industrial interest in utilizing wireless broadcast for pervasive information services. To support location-based services in wireless data broadcast systems, a distributed ...
 
Data Management in Location-Dependent Information Services
Found in: Data Engineering, International Conference on
By Baihua Zheng, Jianliang Xu, Wang-Chien Lee
Issue Date:April 2004
pp. 871
No summary available.
   
Guest Editorial: Special Section on Data Management Systems and Mobile Computing
Found in: IEEE Transactions on Computers
By Pradip K. Srimani, Wang-Chien Lee, Sandeep Kumar S. Gupta
Issue Date:October 2002
pp. 1121-1123
No summary available.
 
Collaborative caching for spatial queries in Mobile P2P Networks
Found in: Data Engineering, International Conference on
By Qijun Zhu,Dik Lun Lee,Wang-Chien Lee
Issue Date:April 2011
pp. 279-290
We propose a novel collaborative caching framework to support spatial query processing in Mobile Peer-to-Peer Networks (MP2PNs). To maximize cache sharing among clients, each client caches not only data objects but also parts of the index structure built o...
 
A Lightweight Multidimensional Index for Complex Queries over DHTs
Found in: IEEE Transactions on Parallel and Distributed Systems
By Yuzhe Tang, Jianliang Xu, Shuigeng Zhou, Wang-Chien Lee, Dingxiong Deng, Yue Wang
Issue Date:December 2011
pp. 2046-2054
In this paper, we study the problem of indexing multidimensional data in P2P networks based on distributed hash tables (DHTs). We advocate the indexing approach that superimposes a multidimensional index tree on top of a DHT - a paradigm that keeps the und...
 
PMSE: A Personalized Mobile Search Engine
Found in: IEEE Transactions on Knowledge and Data Engineering
By Kenneth Wai-Ting Leung,Dik Lun Lee,Wang-Chien Lee
Issue Date:April 2013
pp. 820-834
We propose a personalized mobile search engine (PMSE) that captures the users' preferences in the form of concepts by mining their clickthrough data. Due to the importance of location information in mobile search, PMSE classifies these concepts into conten...
 
Distributed Processing of Probabilistic Top-k Queries in Wireless Sensor Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Mao Ye,Wang-Chien Lee,Dik Lun Lee,Xingjie Liu
Issue Date:January 2013
pp. 76-91
In this paper, we introduce the notion of sufficient set and necessary set for distributed processing of probabilistic top-k queries in cluster-based wireless sensor networks. These two concepts have very nice properties that can facilitate localized data ...
 
On Searching Continuous k Nearest Neighbors in Wireless Data Broadcast Systems
Found in: IEEE Transactions on Mobile Computing
By Baihua Zheng, Wang-Chien Lee, Dik Lun Lee
Issue Date:July 2007
pp. 748-761
A continuous nearest neighbor (CNN) search, which retrieves the nearest neighbors corresponding to every point in a given query line segment, is important for location-based services such as vehicular navigation and tourist guides. It is infeasible to answ...
 
Performance Evaluation of an Optimal Cache Replacement Policy for Wireless Data Dissemination
Found in: IEEE Transactions on Knowledge and Data Engineering
By Jianliang Xu, Qinglong Hu, Wang-Chien Lee, Dik Lun Lee
Issue Date:January 2004
pp. 125-139
<p><b>Abstract</b>—Data caching at mobile clients is an important technique for improving the performance of wireless data dissemination systems. However, variable data sizes, data updates, limited client resources, and frequent client di...
 
An Optimal Cache Replacement Policy for Wireless Data Dissemination under Cache Consistency
Found in: Parallel Processing, International Conference on
By Jianliang Xu, Qinglong Hu, Wang-Chien Lee, Dik Lun Lee
Issue Date:September 2001
pp. 0267
Abstract: A good cache management method for mobile wireless environments has to handle problems associated with limited client resources and frequent client disconnections, in addition to standard problems found in wired environments, such as variable dat...
 
Querying Uncertain Minimum in Wireless Sensor Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Mao Ye,Ken C.K. Lee,Wang-Chien Lee,Xingjie Liu,Meng-Chang Chen
Issue Date:December 2012
pp. 2274-2287
In this paper, we introduce two types of probabilistic aggregation queries, namely, Probabilistic Minimum Value Queries (PMVQ)s and Probabilistic Minimum Node Queries (PMNQ)s. A PMVQ determines possible minimum values among all imprecise sensed data, while...
 
DISQO: A Distributed Framework for Spatial Queries over Moving Objects
Found in: Parallel Processing, International Conference on
By Baihua Zheng, Wang-Chien Lee, Ken C. K. Lee, Julian Winter, Meng-Chang Chen
Issue Date:September 2010
pp. 414-423
This paper presents DISQO, a DIStributed Framework for Spatial Queries over Moving Objects. Distinguished from existing work, DISQO aims at achieving high scalability and system performance in support of both snapshot and continuous spatial queries over mo...
 
Probabilistic Top-k query processing in distributed sensor networks
Found in: Data Engineering, International Conference on
By Mao Ye, Xingjie Liu, Wang-Chien Lee, Dik Lun Lee
Issue Date:March 2010
pp. 585-588
In this paper, we propose the notion of sufficient set for distributed processing of probabilistic Top-k queries in cluster-based wireless sensor networks. Through the derivation of sufficient boundary, we show that data items ranked lower than sufficient ...
 
Personalized Web search with location preferences
Found in: Data Engineering, International Conference on
By Kenneth Wai-Ting Leung, Dik Lun Lee, Wang-Chien Lee
Issue Date:March 2010
pp. 701-712
As the amount of Web information grows rapidly, search engines must be able to retrieve information according to the user's preference. In this paper, we propose a new web search personalization approach that captures the user's interests and preferences i...
 
Nearest Surrounder Queries
Found in: IEEE Transactions on Knowledge and Data Engineering
By Ken C.K. Lee, Wang-Chien Lee, Hong Va Leong
Issue Date:October 2010
pp. 1444-1458
In this paper, we present a new type of spatial queries called Nearest Surrounder (NS) queries. An NS query determines the nearest polygon-shaped spatial objects (referred to as nearest surrounder objects) and their orientations with respect to a query poi...
 
Visible Reverse k-Nearest Neighbor Query Processing in Spatial Databases
Found in: IEEE Transactions on Knowledge and Data Engineering
By Yunjun Gao, Baihua Zheng, Gencai Chen, Wang-Chien Lee, Ken C.K. Lee, Qing Li
Issue Date:September 2009
pp. 1314-1327
Reverse nearest neighbor (RNN) queries have a broad application base such as decision support, profile-based marketing, resource allocation, etc. Previous work on RNN search does not take obstacles into consideration. In the real world, however, there are ...
 
Visible Reverse k-Nearest Neighbor Queries
Found in: Data Engineering, International Conference on
By Yunjun Gao, Baihua Zheng, Gencai Chen, Wang-Chien Lee, Ken C. K. Lee, Qing Li
Issue Date:April 2009
pp. 1203-1206
Reverse nearest neighbor (RNN) queries have a broad application base such as decision support, profile-based marketing, resource allocation, data mining, etc. Previous work on RNN search does not take obstacles into consideration. In the real world, howeve...
 
OPAQUE: Protecting Path Privacy in Directions Search
Found in: Data Engineering, International Conference on
By Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Baihua Zheng
Issue Date:April 2009
pp. 1271-1274
Directions search returns the shortest path from a source to a destination on a road network. However, the search interests of users may be exposed to the service providers, thus raising privacy concerns. For instance, a path query that finds a path from a...
 
Tuning On-Air Signatures for Balancing Performance and Confidentiality
Found in: IEEE Transactions on Knowledge and Data Engineering
By Baihua Zheng, Wang-Chien Lee, Peng Liu, Dik Lun Lee, Xuhua Ding
Issue Date:December 2009
pp. 1783-1797
In this paper, we investigate the trade off between performance and confidentiality in signature-based air indexing schemes for wireless data broadcast. Two metrics, namely, false drop probability and false guess probability, are defined to quantify the fi...
 
Rule-Based WiFi Localization Methods
Found in: Embedded and Ubiquitous Computing, IEEE/IFIP International Conference on
By Qiuxia Chen, Dik-Lun Lee, Wang-Chien Lee
Issue Date:December 2008
pp. 252-258
The rule-based localization methods proposed in this paper are based on two important observations. First, although the absolute RSS values change with time, the relative RSS (RRSS) values between several Access Points (APs) are more stable than the absolu...
 
Location-Dependent Skyline Query
Found in: Mobile Data Management, IEEE International Conference on
By Baihua Zheng, Ken C. K. Lee, Wang-Chien Lee
Issue Date:April 2008
pp. 148-155
Given a set of data points with both spatial coordinates andnon-spatial attributes, point a location-dependently dominates point b with respect to a query point q if a is??closer to q than b and meanwhile a dominates b. A location-dependent skyline query (...
 
Ranked Reverse Nearest Neighbor Search
Found in: IEEE Transactions on Knowledge and Data Engineering
By Ken C.K. Lee, Baihua Zheng, Wang-Chien Lee
Issue Date:July 2008
pp. 894-910
Given a set of data points P and a query point q in a multidimensional space, Reverse Nearest Neighbor (RNN) query finds data points in P whose nearest neighbors are q. Reverse k-Nearest Neighbor (RkNN) query (where k ≥ 1) generalizes RNN query to find dat...
 
In-broker Access Control: Towards Efficient End-to-End Performance of Information Brokerage Systems
Found in: Sensor Networks, Ubiquitous, and Trustworthy Computing, International Conference on
By Fengjun Li, Bo Luo, Peng Liu, Dongwon Lee, Prasenjit Mitra, Wang-Chien Lee, Chao-Hsien Chu
Issue Date:June 2006
pp. 252-259
An XML brokerage system is a distributed XML database system that comprises data sources and brokers which, respectively, hold XML documents and document distribution information. However, all existing information brokerage systems view or handle query bro...
 
Learning metadata from the evidence in an on-line citation matching scheme
Found in: Digital Libraries, Joint Conference on
By Anand Sivasubramaniam, Sandip Debnath, Huajing Li, Wang Chien Lee, Levent Bolelli, C. Lee Giles, Ziming Zhuang, Isaac G. Councill
Issue Date:June 2006
pp. 276-285
Citation matching, or the automatic grouping of bibliographic references that refer to the same document, is a data management problem faced by automatic digital libraries for scientific literature such as CiteSeer and Google Scholar. Although several solu...
 
Tracking Nearest Surrounders in Moving Object Environments
Found in: International Conference on Pervasive Services
By Lee, Schiffman, Baihua Zheng, Wang-Chien Lee, Hong Va Leong
Issue Date:June 2006
pp. 3-12
No summary available.
 
Nearest Surrounder Queries
Found in: Data Engineering, International Conference on
By Ken C.K. Lee, Wang-Chien Lee, Hong Va Leong
Issue Date:April 2006
pp. 85
In this paper, we study a new type of spatial query, Nearest Surrounder (NS), which searches the nearest surrounding spatial objects around a query point. NS query can be more useful than conventional nearest neighbor (NN) query as NS query takes the objec...
 
Supporting Complex Multi-Dimensional Queries in P2P Systems
Found in: Distributed Computing Systems, International Conference on
By Bin Liu, Wang-Chien Lee, Dik Lun Lee
Issue Date:June 2005
pp. 155-164
More and more applications require peer-to-peer (P2P) systems to support complex queries over multi-dimensional data. For example, a P2P auction network for real estate frequently needs to answer queries such as
 
The D-Tree: An Index Structure for Planar Point Queries in Location-Based Wireless Services
Found in: IEEE Transactions on Knowledge and Data Engineering
By Jianliang Xu, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee
Issue Date:December 2004
pp. 1526-1542
Location-based services (LBSs), considered as a killer application in the wireless data market, provide information based on locations specified in the queries. In this paper, we examine the indexing issue for querying location-dependent data in wireless L...
 
Energy Efficient Index for Querying Location-Dependent Data in Mobile Broadcast Environments
Found in: Data Engineering, International Conference on
By Jianliang Xu, Baibua Zheng, Wang-Chien Lee, Dik Lun Lee
Issue Date:March 2003
pp. 239
We are witnessing in recent years growing interest for location-dependent information services among mobile users. This paper examines the issue of processing location-dependent queries in a mobile broadcast environment. Different from a traditional enviro...
 
Data management in location-dependent information services
Found in: IEEE Pervasive Computing
By Dik Lun Lee, Jianliang Xu, Baihua Zheng, Wang-Chien Lee
Issue Date:July 2002
pp. 65,66,67,68,69,70,71,72
Location-dependent information services have great promise for mobile and pervasive computing environments. They can provide local and nonlocal news, weather, and traffic reports as well as directory services. Before they can be implemented on a large scal...
 
Power Conservative Multi-Attribute Queries on Data Broadcast
Found in: Data Engineering, International Conference on
By Qinglong Hu, Wang-Chien Lee, Dik Lun Lee
Issue Date:March 2000
pp. 157
In this paper, we study power conservation techniques for multi-attribute queries on wireless data broadcast channels. Indexing data on broadcast channels can improve client filtering capability, while clustering and scheduling can reduce both access time ...
 
Path Dictionary: A New Access Method for Query Processing in Object-Oriented Databases
Found in: IEEE Transactions on Knowledge and Data Engineering
By Wang-Chien Lee, Dik Lun Lee
Issue Date:May 1998
pp. 371-388
<p><b>Abstract</b>—We present a new access method, called the path dictionary index (PDI) method, for supporting nested queries on object-oriented databases. PDI supports object traversal and associative search, respectively, with a path ...
 
A Comparision of Indexing Methods for Data Broadcast on the Air
Found in: Information Networking, International Conference on
By Qinglong Hu, Dik Lun Lee, Wang-Chien Lee
Issue Date:January 1998
pp. 0656
Abstract: Several indexing techniques for data broadcast on the air has been proposed for power conservation on mobile computers in the past few years. Indexing techniques for broadcast channels can save battery power (estimated by tune-in time) while incu...
 
On processing nested queries in distributed object-oriented database systems
Found in: Research Issues in Data Engineering, International Workshop on
By Wang-Chien Lee, Dik Lun Lee
Issue Date:March 1995
pp. 10
In this paper, we discuss nested query processing in a distributed object-oriented database system. We present three query processing strategies to exploit parallelism in a distributed environment. Then, we review three access methods designed for centrali...
 
U-Skyline: A New Skyline Query for Uncertain Databases
Found in: IEEE Transactions on Knowledge and Data Engineering
By Xingjie Liu,De-Nian Yang,Mao Ye,Wang-Chien Lee
Issue Date:April 2013
pp. 945-960
The skyline query, aiming at identifying a set of skyline tuples that are not dominated by any other tuple, is particularly useful for multicriteria data analysis and decision making. For uncertain databases, a probabilistic skyline query, called P-Skyline...
 
Energy-Aware Set-Covering Approaches for Approximate Data Collection in Wireless Sensor Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Chih-Chieh Hung,Wen-Chih Peng,Wang-Chien Lee
Issue Date:November 2012
pp. 1993-2007
To conserve energy, sensor nodes with similar readings can be grouped such that readings from only the representative nodes within the groups need to be reported. However, efficiently identifying sensor groups and their representative nodes is a very chall...
 
Parallelizing Itinerary-Based KNN Query Processing in Wireless Sensor Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Tao-Yang Fu, Wen-Chih Peng, Wang-Chien Lee
Issue Date:May 2010
pp. 711-729
Wireless sensor networks have been proposed for facilitating various monitoring applications (e.g., environmental monitoring and military surveillance) over a wide geographical region. In these applications, spatial queries that collect data from wireless ...
 
Analysis of TTL-Based Consistency in Unstructured Peer-to-Peer Networks
Found in: IEEE Transactions on Parallel and Distributed Systems
By Xueyan Tang, Jianliang Xu, Wang-Chien Lee
Issue Date:December 2008
pp. 1683-1694
Consistency maintenance is important to the sharing of dynamic contents in peer-to-peer (P2P) networks. The TTL-based mechanism is a natural choice for maintaining freshness in P2P content sharing. This paper investigates TTL-based consistency maintenance ...
 
A New Storage Scheme for Approximate Location Queries in Object-Tracking Sensor Networks
Found in: IEEE Transactions on Parallel and Distributed Systems
By Jianliang Xu, Xueyan Tang, Wang-Chien Lee
Issue Date:February 2008
pp. 262-275
Energy efficiency is one of the most critical issues in the design of wireless sensor networks. Observing that many sensor applications for object tracking can tolerate a certain degree of imprecision in the location data of tracked objects, this paper stu...
 
Top-k Monitoring in Wireless Sensor Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Minji Wu, Jianliang Xu, Xueyan Tang, Wang-Chien Lee
Issue Date:July 2007
pp. 962-976
Top-k monitoring is important to many wireless sensor applications. This paper exploits the semantics of top-k query and proposes an energy-efficient monitoring approach called FILA. The basic idea is to install a filter at each sensor node to suppress unn...
 
ProcessingWindow Queries in Wireless Sensor Networks
Found in: Data Engineering, International Conference on
By Yingqi Xu, Wang-Chien Lee, Jianliang Xu, Gail Mitchell
Issue Date:April 2006
pp. 70
The existing query processing techniques for sensor networks rely on a network infrastructure for query propagation and data collection. However, such an infrastructure is very susceptible to network topology transients that widely exist in sensor networks...
 
PSGR: priority-based stateless geo-routing in wireless sensor networks
Found in: IEEE International Conference on Mobile Adhoc and Sensor Systems Conference
By Yingqi Xu, Wang-Chien Lee, Jianliang Xu, G. Mitchell
Issue Date:November 2005
pp. 680
Volunteer forwarding, as an emerging routing idea for large scale, location-aware wireless sensor networks, recently has attracted a significant amount of research attention. However, several critical research issues raised by volunteer forwarding, includi...
 
Energy Efficient Processing of K Nearest Neighbor Queries in Location-aware Sensor Networks
Found in: Mobile and Ubiquitous Systems, Annual International Conference on
By Julian Winter, Yingqi Xu, Wang-Chien Lee
Issue Date:July 2005
pp. 281-292
<p>The k nearest neighbor (KNN) query, an essential query for information processing in sensor networks, has not received sufficient attention in the research community of sensor networks. In this paper, we examine in-network processing of KNN querie...
 
On Alleviating Beacon Overhead in Routing Protocols for Urban VANETs
Found in: 2013 14th IEEE International Conference on Mobile Data Management (MDM)
By Yuya Sasaki,Wang-Chien Lee,Takahiro Hara,Shojiro Nishio
Issue Date:June 2013
pp. 66-76
Vehicular ad hoc networks (VANETs) have been attracting increasing research interests for the past decade. To address the routing problem, many protocols have been proposed in the past several years. Routing protocols for VANETs, mostly based on the ideas ...
 
Efficient Time Series Disaggregation for Non-intrusive Appliance Load Monitoring
Found in: 2012 IEEE 9th Int'l Conference on Ubiquitous Intelligence & Computing / 9th Int'l Conference on Autonomic & Trusted Computing (UIC/ATC)
By Yao-Chung Fan,Xingjie Liu,Wang-Chien Lee,Arbee L.P. Chen
Issue Date:September 2012
pp. 248-255
The growing concerns on urgent environmental and economical issues, such as global warming and rising energy cost, have motivated research studies on various green computing technologies. For example, Non-Intrusive Appliance Load Monitor (NIALM) techniques...
 
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