• Journal of IKEEE
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• v.11 no.4
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• pp.227-234
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• 2007

In this paper, to support a QoS level appropriate to the user in Wireless Home Network based Wireless LAN, we propose a QoS support architecture which includes Wired Network and Wireless Network. Actually, an important problem to support QoS in Wireless Home Network is approached not only on a MAC level in Wireless LAN but also on a integrated method to combine Network layer with Datalink layer. By applying the integrated QoS support method, it is possible to provide QoS support architecture using a Wireless LAN terminal with a minimum changing, and the proposed scheme has advantage of QoS support method, which is more superior than a existing scheme to support QoS in MAC level of Wireless LAN. Simulations results show that overall performance of the proposed scheme can be improved.

• Journal of Advanced Navigation Technology
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• v.12 no.2
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• pp.91-99
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• 2008

In this paper, we implemented an wireless remote control and monitoring system by using Globalstar satellite modem. This system is composed of the data terminal equipment of Globalstar data communication system using microcontroller, C8051F023, and WGIS(Web-based GIS) user program. We tested the wireless remote control and monitoring system with data terminal equipment and user program how to work properly, and verified that the user could confirm the data from the data terminal equipment, which can provide the status of input/output devices and the information of location with the main and control dialog by GIS(Geographic Information System) program. For data communication of between data terminal equipment and user program, we programed PPP and TCP/IP protocol to communicate with each other. Some GIS tools used in this program are ArcView and MapObject from ESRI to offer various visual mapping information to the user.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1194-1199
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• 2002

There is big problem that must change contents that is made out by HTML to service existent wire HTML contents in wireless environment to WML, HDML, mHTML. It is Markup language automatic conversion engine that is proposed to solve these problem. But, facility that studied most Markup language automatic conversion engines process text and image information so far is not sufficient. In this thesis, image file format that wireless terminal supports image on wire internet, presented mechanism that change real time automatic and algorithm that can do to optimize output of image which consider screen size of wireless terminal.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.107-107
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• 2000

This paper focuses on a method to connect mobile devices such as mobile robot, ACV and UTC with Profibus network. In this paper, the IEEE 802.11 wireless LAN is used for wireless extension of Frofibus, and four major issues are introduced to implement the wireless extended Profibus; First, the integration method between Profibus and IEEE 802.11 is introduced. Second, the implementation method of gateway is proposed. Three, the virtual polling mode algorithm is developed for satisfaction of real-time characteristics required in industrial network. Finally, we implement a experimental model, and carried out the performance analysis of wireless extended Profibus. This results show that wireless extended Profibus is suitable to industrial network such as automated container terminal.

• Journal of information and communication convergence engineering
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• v.5 no.2
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• pp.93-97
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• 2007

In this paper, centralized access control and slot allocation algorithm is proposed for wireless networks. The proposed algorithm is characterized by the contention-based reservation. In order to reduce the collision probability of reservation request, the base station calculates and broadcasts the transmission probability of reservation requests, and the wireless terminal transmits its reservation request with the received transmission probability. The scheduler allocates the uplink data slots based on the successful reservation requests. Simulation results show that the proposed algorithms can provide high channel utilization, and furthermore, maintains constant delay performance in the heavy traffic environment.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.119-122
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• 1998

Wireless ATM(WATM) intends to provide a broad range of mobile multimedia services through wireless access by mobility extensions from the fixed ATM-based network. Recently, there have been active researches about new handover techniques to support terminal mobility in WATM. In this paper we classify path reestablishment schemes into full reestablishment, path rerouting with a static COS, path rerouting with a dynamic COS, and path extension. For a backward lossy handover procedure, we analyze and compare the performances of path reestablishment schemes in terms of delay, service disruption time and cell loss.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.394-397
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• 2012

Wireless sensor network is configured to be able to collect information collected from the various sensors, real-world environment wireless network. In this paper, the information collected from the wireless sensor networks in the real world using AR (Augmented Reality) data by projecting, in a variety of ways, the information collected from the wireless sensor network is utilized, which more intuitive is intended to provide to users. In this paper, stored in the DB table and the information collected from the wireless sensor network, wireless LAN (Access Point) that are placed in the sensor field and the terminal attached to the geomagnetic sensor, terminal position, after correction using acceleration sensors and augmented reality the aim is to visualize the data stored in the DB table using.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.281-288
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• 2015

The container terminals use convergence technology that exchange information for cargo work, using wireless communication between the TOS(Terminal Operations System) and the handling equipments(CC, TC, YT). But if the container cargoes pile up high in the container yard, delayed cargo work and cargo working list information error happen because of communication dead spots(the worker can not receive the information) which wireless communication is disconnected. At this time the driver of the yard tractor(YT) must be able to recognize the communication state. If then, delayed cargo work and cargo working list information errors that occur in the shaded communication area can be avoided, and can process the delayed work due to wireless communication break. In this project, we have built wireless communication environment to increase the efficiency of the loading and unloading operations which the operator can respond actively, when the work is delayed and work orders result in errors. That is, the flow of the wireless communication module has been changed.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.4
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• pp.349-355
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• 2008

In this paper, a wireless remote monitoring system for leakage current of distribution board is developed. In the developed system, signals of the leakage current of distribution board are transmitted to a monitoring system using wireless communication. The developed system is consisted of a comparative module, control module, a wireless communication module, and hand held terminal. The developed system has any facilities which can check a leakage current with real time, send to the user this fact using a wireless remote interface method. And also developed system can take precaution for an accident by leakage current.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4B
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• pp.704-712
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• 2010

Recently, the lack of the frequency have been emerged due to the use of various wireless terminals. To find solutions for obtaining new frequency resources and for avoiding an interference, a cognitive radio technology have focused on as the new technology that can use the whitespace in TV broadcasting band. In this paper, the Cognitive Radio terminal system for whitespace in TV band is first introduced. The purpose of the CR terminal platform is to evaluate the feasibility of the unlicensed wireless service in the TV band. Then, we design and develop the software for Sensing MAC applied the cognitive radio terminal system. The developed Sensing MAC software based on IEEE 802.22 specification can be aware of using the whitespace in TV band that operates on cognitive radio terminal system. Finally, we have tested for evaluating the sensing MAC module.