• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.6B
• /
• pp.527-533
• /
• 2006

In this paper, we analyze the performance of MAC (Media Access Control) layer in DSRC (Dedicated Short Range Communication). It will be widely applied for ITS (Intelligent Transportation System) services; for example ETC (Electric Toll Control), BIS (Bus Information System) etc., needed to small packet size. But If ITS service is evolving to advance ITS, ADIS (Advanced Driver Information Systems) and AVHS (Advanced Vehicle Highway System) etc, be needed larger packet size. In the future, it may offer more various services such as traffic information, collection, and multimedia information. There are two kind of physical media, IR(Infrared) and RF(Radio frequency). And each system has their own protocol that is adaptive in special characteristics of physical medium for using efficiently limited radio resources. In this paper, we analyze the special characteristics of each system. And we study practical use of some related services expected to be used in the near future, by analyzing the transmission efficiency in each DSRC system.

• The KIPS Transactions:PartC
• /
• v.13C no.5 s.108
• /
• pp.641-650
• /
• 2006

There has been a continued increase in the complexity of software equipped with wireless mobile devices, due to the introduction of new device functionality and services via network connection. The increasement expected to be accelerated by convergence of telecommunication and broadcasting, and proliferation of telematics and home networking services using wireless mobile devices. The higher the complexity of mobile device software, the higher the necessity of management for the software. As for the global standard of mobile device management technology, OMA DM has been widely adopted by device manufacture and expected to be accelerated its adoption. In this paper, we present a development result of mobile device software release management system ThinkSync DM SoftMan. The implementation details of ThinkSync DM SoftMan are provided in implementation architecture and its working scenario based on the design of ThinkSync DM SoftMan that is summarized in this paper as our previous work. The conformance and performance test of the system are presented.

• The Journal of the Korea Contents Association
• /
• v.7 no.5
• /
• pp.138-145
• /
• 2007

Mobile network evolution and development of USN technologies introduce new business model based on context awareness. Cellular operators provide friend finding service using cell based location information and telematics service using GPS location information. Recently cellular operators provide yellow page service based cell based location information. In this paper, we develop mobile tour application on WIPI platform based on location information. Mobile tour information services provide the best information based on context awareness using user location information from LBS(Location Based Service) Platform, season, weather conditions, time from Web server, and personal preference information stored in database. Mobile tour information service application is developed on WIPI platform.

• Journal of Korea Spatial Information System Society
• /
• v.7 no.3 s.15
• /
• pp.45-53
• /
• 2005

Nowadays, using the mobile communication devices, such as a mobile phone, PDA, telematics device, and so forth, are increasing. The large parts of the services with these mobile devices are the position tracking and the route planning. For offering these services, it is increasing the use of the spatial data on the mobile environment. Although the storage of mobile device expands more than before, it still lacks the necessary storage on the spatial data. In this paper, lossy compression technique on the spatial data is suggested, and then it is analyzed the compression ratio and the amount of loss data by the test. Suggested compression technique on the spatial data at this paper is applied to the real-data, and others methods, suggested at the previous studies, is applied to same data. According as the results from both are compared and analyzed, compression technique suggested at this study shows better performance when the compression result is demanded the high position accuracy.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.1 s.39
• /
• pp.87-96
• /
• 2006

Selectivity estimation is one of the query optimization techniques. It is difficult for the previous selectivity estimation techniques for moving objects to apply the position change of moving objects to synopsis. Therefore, they result in much error when estimating selectivity for queries, because they are based on the extended spatial synopsis which does not consider the property of the moving objects. In order to reduce the estimation error, the existing techniques should often rebuild the synopsis. Consequently problem occurs, that is, the whole database should be read frequently. In this paper, we proposed a moving object histogram method based on quad tree to develop a selectivity estimation technique for moving object queries. We then analyzed the performance of the proposed method through the implementation and evaluation of the proposed method. Our method can be used in various location management systems such as vehicle location tracking systems, location based services, telematics services, emergency rescue service, etc in which the location information of moving objects changes over time.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.1
• /
• pp.66-74
• /
• 2007

The most commonly used navigation systems work on Windows CE platforms. Linux-based embedded terminals have price competitiveness, because Linux is a free operation system. In order to develop map services on Linux-based embedded terminals, there were a number of technical hurdles that had to be resolved. Since the Linux-based embedded terminals is a low power, low cost, and small size platform with low processing capabilities, we must have developed the spatial database engine that minimize the number of disk accesses. We solved problems that are the processing korean language and the lack of debugging tools on Linux. In this paper, we has developed the spatial database engine and user interfaces on hand-held terminals based on embedded Linux for implementing the location based map system With view of this implementation results, we confirmed the possibility of using our embedded linux terminal as telematics terminals or navigation terminals.

• Journal of Korea Spatial Information System Society
• /
• v.7 no.3 s.15
• /
• pp.93-106
• /
• 2005

Recently, the web map services with standard interfaces have been developed to a high degree for the purpose of sharing of spatial data through the web. Among the various kinds of works related, the specification for the web map service released by Open Geospatial Consortium (OGC) is the most prominent, and is nearly adopted as international standard (ISO/DIS 19128) in developing the web map servers. The web map server of OGC, however, provides the insufficient capabilities for mobile applications. Unlike the wired applications, the mobile applications would require the map server to minimize of size of data transferred, because the size of data is very important factor in communication cost and the response time of map clients. And the mobile applications require different quality of map according to the screen size of mobile devices. The mobile application, also require some application specific queries. In this paper, We have Proposed the interfaces for mobile web map services (M-WMS) which fully comply with the standard interfaces proposed in OGC. And we have designed and implemented the web map server for mobile map services. This paper has contributed to construction and practical use of the web map servers in mobile applications, such as LBS and telematics.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.30B no.10
• /
• pp.59-68
• /
• 1993

This paper describes implemation of 'General-purpose ETRI MAP interface module' (GEM) for Mini-MAP network. GEM operates as a Mini-MAP node in our FA system. To communicate between GEM and programmable devices(PD) such as PLC and CNC, serial communication is used. Application programs of a MiNi-MAP host system control and monitor programmable devices via GEM. GEM is implemented and tested on the basis of the MAP 3.0. TBC in the Nini-MAP board performs the function of the MAC sublayer. The LLC sublayer is implemented according to the specification of Class 3 that includes Type 1 and 3. And the MMS services are designed within the scope of implementation class MAP3. All the softwares are implemented under the real-time multitask OS for real-time application of the Mini-MAP and they are loaded into PROMs at the network board of GEM. We tested the LLC functions to make use of a protocol analyzer for the token-passing protocol. Also the MMS conformance test was carried out by exchanging primitives between GEM and a MMS product that had already passed the conformance test. Therefore GEM is proposed as a network tool of Computer Integrated Manufacturing (CIM) to integrate PDs which don't support MAP functions.

• Proceedings of the Korea Contents Association Conference
• /
• 2006.11a
• /
• pp.355-359
• /
• 2006

Mobile network evolution and development of USN technologies introduce new business model based on context awareness. Cellular operators provide friend finding service using cell based location information and telematics service using GPS location information. Recently cellular operators provide yellow page service based cell based location information. In this paper, we develop mobile tour application on WIPI platform based on location information. Mobile tour information services provide the best information based on context awareness using user location information from LBSP (Location Based Service Platform), season, weather conditions, time from Web server, and personal preference information stored in database. Mobile tour information service application is developed on WIPI platform.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.2
• /
• pp.196-200
• /
• 2008

Recently, the query processing algorithm in spatial network database (SNDB) has attracted many interests. However, there is little research on route-based query processing algorithm in SNDB. Since the moving objects moves only in spatial networks, the route-based algorithm is very useful for LBS and Telematics applications. In this paper, we analyze In-Route Nearest Neighbor (IRNN) query, which is an typical one of route-based queries, and propose a new IRNN query processing algorithm with time constraint. In addition, we show from our performance analysis that our IRNN query processing algorithm with time constraint is better on retrieval performance than the existing IRNN query processing one.