• Journal of Communications and Networks
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• v.7 no.4
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• pp.478-488
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• 2005

To conserve the usage of energy, indexing techniques have been developed in a wireless mobile environment. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, we present the broadcast-based location dependent data delivery scheme (BBS) for dynamic range queries. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, we present a data prefetching and caching scheme, designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients, and the size of the service area.

• Journal of KIISE:Databases
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• v.32 no.4
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• pp.405-415
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• 2005

Indexing techniques are used to implement selective tuning in wireless environments Indices are broadcast together with data to help mobile clients locate the required information. As a result, clients stay in doze mode most of the time. The drawback of this solution is that broadcast cycles are lengthened due to additional index information. In location-aware mobile services(LAMSs), it is important to reduce the query response time, since a late query response nay contain out-of-date information. In this paper, we present a broadcast-based spatial query processing method (BBS) designed to support k-NN query processing. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.6
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• pp.1-8
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• 2013

Recently, as increasing use of smartphone, the development of social network service(SNS) applications is very active because of the mobility of smartphone. In addition, as the demand of the location based service(LBS) supporting mobile information is expanded, LBS combined with SNS improves the usability of smart phones. This paper proposes the smartphone application that provides the information for SNS generated depending on the location, by tracking the user's location in real time.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.4
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• pp.227-248
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• 1998

Intranet is an internal information system which utilizes Intranet technology. Intranet is quickly adopted by many organizations worldwide. Electronic survey was conducted in Korea Electric Power Corporation where part of the information systems are offered by the Web-based systems. 842 questionnaires were analyzed to investigate the usage of the information systems and the Internet to access information. Some heavily-used and hard-to-access internal publications and outside publications were identified, and investigated whether they would be accessed via the information systems, the Internet, and the BBS. The study also Identified some problems associated with the information systems, md the users' preference of Web-based services was also examined. It was also examined whether the usage of the information systems, the Internet, and the BBS was different by some factors such as the kinds of work, the years at work, and the location of work. In conclusion, this study recommends that the Intranet should be established linking all the current systems of the company to provide wide variety of information the users want.