• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.243-245
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• 2004

This paper proposes design and implementation for Seamless Handoff method between adapters in a system environment where both wired and wireless adapters are present First of all, by settingLayer 2 address of wired adapter to Layer 2address of wireless adapter, then generate virtual adapter on the above layer to make these two adapters operate on an IP address. Under the condition, when wired communication via the wired adapter gets disconnected while in service, wireless handoff occurs by mapping information on the wireless adapter to the virtual adapter. According to the method proposed in this paper, continuous session can be obtained even when handoff between wired and wireless adapters occurs at lower level in an application where both IP address and Port address are used to maintain session since If address does not change.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.3
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• pp.324-340
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• 2010

Video streaming service over wireless networks is a challenging task because of the changes in the wireless channel conditions that can occur due to interference, fading, and station mobility. To provide an efficient wireless video streaming service, the rate adaptation scheme should improve wireless node performance and channel utilization. Moreover, the quality adaptation scheme should be considered at the streaming application. To meet these requirements, we propose a new cross-layer design for video streaming over wireless networks. This design includes the rate and quality adaptation schemes. The rate adaptation scheme selects the optimal transmission mode and resolves the performance anomaly problem. Based on performance improvement by the proposed rate adaptation scheme, our quality adaptation scheme improves the quality of video streaming. Through performance evaluations, we prove that our cross-layer design improves the wireless channel utilization and the quality of video streaming.

• Review of KIISC
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• v.10 no.4
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• pp.41-51
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• 2000

무선 인터넷 서비스가 국내외적으로 크게 증가하고 있으며 2003년경에는 세계 무선 인터넷 사용인구가 6억 명에 이를 것이라는 전망이 나오고 있다. 그러나 무선인터넷이 보다 활성화되고 이를 이용한 뱅킹 서비스, 주식거래, 온라인 쇼핑 등의 전자상거래 서비스가 원활히 제공되기 위해서는 보안기술의 적용이 필수 사항이다. 본 고에서는 WAP(Wireless Application Protocol)을 위한 전자서명인증 및 키 분배용 모델을 제시함으로써 국내 무선공개키기반구조 구축시 발생할 수 있는 혼란을 최소화하고 국내 무선 인터넷 인증 관련 기술의 발전과 응용 서비스를 활성화시키는데 기여하고자 한다.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.597-600
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• 2005

The software streaming technology enables telematics software to be automatically updated through a wireless network. When the software starts running, software streaming system inspects its version and then, automatically download latest one. The software streaming system breaks the software into several pieces that are streamed to the user as needed. In this way, software streaming system can improves the telematics application load time while updating the software through wireless network. In our experiments, the application load time was reduced about 7 times compared to downloading whole software at best case.

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.149-152
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• 2001

In general, the wireless services based on markup language and provided with wired network requires dedicated gateway system. But in this case, the serious problems such as security vulnerabilities, damage of contents are occurred to the application. In this paper, to improve above problems, we designed and implemented the new application named "Interacted Wired St Wireless Student Information System" using J2ME(Java 2 Micro Edition) platform and XML(eXtensible Markup Language) to transmit user data safely and support the system extendibility maintaining data format consistency respectively.pectively.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.132-134
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• 2000

무선 인터넷의 급속한 발전과 더불어 모바일 인터넷에서 요구되는 기능이 점점 다양화되어 가고 있다. 특히 WAP)Wireless Application Protocol)상에서 지원되는 Push 서비스의 요구가 늘어나고 있다. 본 논문에서는 WAP상에서 사용하는 Push message의 보다 쉬운 구현을 위해 Push 서비스의 구조와 동작 원리를 이해하고 Push Content Generator의 설계에 대해 기술한다.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.1
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• pp.50-57
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• 2000

By supporting wireless communication technology, there is gradually expansion of the commercial application for Wireless Local Loop(WLL) technology, which is to replace existing telephone line with wireless one. The WLL system application helps a operator to have merits of the installation and maintenance of line and also a subscriber to make a high speed value-added service. As mentioned above reasons for both sides, many manufactories and operators are concerned with development and application respectively. This paper presents hardware implementation of Radio Port Controller(RPC) and also describes the system configuration, functions, and Inter Processor Communication(IPC) structure of RPC. We performed inter-module communication test via IPC backplane bus. And inter-module integration test also completed through data communication and signal waveform measurement repeatedly.

• Journal of Korea Multimedia Society
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• v.17 no.4
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• pp.441-457
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• 2014

Observed from the recent performance evaluation of clustering schemes in wireless sensor networks, we found that most of them did not consider various sensor characteristics and its application environment. Without considering these, the performance evaluation results are difficult to be trusted because these networks are application-specific. In this paper, for the fair evaluation, we measured several clustering scheme's performance variations in accordance with sensor data pattern, number of sensors per node, density of points of interest (data density) and sensor coverage. According to the experiment result, we can conclude that clustering methods are easily influenced by POI variation. Network lifetime and data accuracy are also slightly influenced by sensor coverage and number of sensors. Therefore, in the case of the clustering scheme that did not consider various conditions, fair evaluation cannot be expected.

• International Journal of Computer Science & Network Security
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• v.22 no.6
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• pp.63-66
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• 2022

The article discusses the application of the IoT concept in the sensitive field of medical devices on the example of a developed prototype of a mechanotherapeutic simulator. Mechanotherapy is a complex of therapeutic, preventive, and restorative exercises conducted using simulators, specially designed for developing movements in individual joints. Mechanotherapy is used for the early and painless restoration of joint mobility, to prevent complications associated with prolonged immobilization of the injured area of extremities. Using the mechanotherapy simulator allows developing the joint painlessly, which accelerates the metabolism in the injured area, and soft tissues are restored to normal. The article provides information about the electronic components that ensure the wireless operation of the device and describes in detail the applied software as well as the client application for a mobile device.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.313-319
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• 2000

In this paper, we proposed the model of wireless communication for ACTS using DSRC and the DSRC system for T/C. The proposed wireless communication model is how to join with DSRC and other wireless communication in port. The DSRC system for T/C is the first application to the unit of port Facilities Automation on stacking area. The DSRC system is communicated between OBE and RSE using 5.8Hz ISM band frequency. The previous works of DSRC applications are gate automation. In these cases, the road trackers are difficult to obtain information of the port in the stacking area. So we used the DSRC for the wireless communication for the port Facilities Automation. Using DSRC, the load trackers obtain more information in the port and contacts to ITS on back-roads of port. The proposed communication system is serviced to reelection of port statistics.