2007, Vol.12, No.4

Journal of The Korea Society of Computer and Information 2023 KCI Impact Factor : 0.65

pISSN : 1598-849X / eISSN : 2383-9945
https://journal.kci.go.kr/jksci

This paper describes the development of a network-based passenger information system(PIS) which provides the convenience of the passenger of the train and heightens the effect of the subtitle service, the advertising and the shelter guidance broadcasting against the urgent event. The existing system uses VGA signal distributor in order to broadcast information with image and subtitle and voice guidance. In this paper we improve the existing system by applying the UDP and TCP/IP protocol and use a reference clock to solve a data loss and synchronization problem which occurs in this case. We also developed an XML-based subtitle authoring tool which can edit and play the subtitles with various 3D to improve the automatic guidance broadcasting and advertisement effect according to the operation schedule of the train. The system performance was evaluated through a simulation.

This paper proposes RCB(Reduced Compact Binary) trie to correct faults of both CB(Compact Binary) trie and HCB(Hierarchical Compact Binary) trie. First, in the case of CB trie, a compact structure was tried for the first time, but as the amount of data was increasing, that of inputted data gained and much difficulty was experienced in insertion due to the dummy nods used in balancing trees. On the other hand, if the HCB trie realized hierarchically, given certain depth to prevent the map from increasing on the right, reached the depth, the method for making new trees and connecting to them was used. Eventually, fast progress could be made in the inputting and searching speed, but this had a disadvantage of the storage space becoming bigger because of the use of dummy nods like CB trie and of many tree links. In the case of RCB trie in this thesis, the tree-map could be reduced by about 35% by completely cutting down dummy nods and the whole size by half, compared with the HCB trie.

This paper presents an SOA framework that enables smooth provision of service to ordinary users while also replacing the current B2B environment-oriented SOA framework. To that end, the proposed SOA will be reviewed for its concept, characteristics, and components. Key to its design is that it will be implemented using the prospective next-generation P2P platform known as JXTA. The proposed framework includes all the basic functions of other SOA frameworks, and will make provision and use of services more easy compared with other frameworks. Under this service, data and applications controlling these data are provided in an enabling format, thereby addressing security problems. Another advantage of this proposed framework is that each peer is able to play all roles of a service provider, service client, and service registry.