• Information and Communications Magazine
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• v.19 no.9
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• pp.77-85
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• 2002

In this paper, we introduce an ADSRC(hdvanced DSRC) OFDM packet communication system which has been developed by ETRI. The ADSRC system is targeted to provide high terminal mobility, high data rate and seamless service in roadside environment for mobile office services. We discuss the requirements of the ADSRC communication system for mobile office services, and the system design specification to meet them with regard to air interface. The ADSRC packet communication systems consist of the MAC processor block, the OFDM packet modem block and the RF block. The MAC processor block handles medium access control and the test. The OFDM packet modem transmits data packets at up to 24Mbps adaptively and recovers the data from RF block. We describe the ADSRC packet communication system architecture and the ADSRC system protocol.

• The Journal of the Korean dental association
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• v.58 no.5
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• pp.304-310
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• 2020

Peri-implantitis refers to the development of inflammation around the implant. Peri-implantitis refers to inflammation accompanied by uptake of bone in the submucosa. Perhaps the most serious of the symptoms of peri-implantitis is the mobility of the implant. Peri-implantitis may occur more frequently in patients with periodontitis than in patients without periodontitis. Therefore, regular checkups and plaque control are more important and important when implants are placed in patients involved with gingivitis or periodontitis. There are many factors such as plaque, calculus and smoking, which can cause peri-implantitis. However, regular plaque management can prevent and reduce the incidence of peri-implantitis. In conclusion, it is important to successfully surgery implants in patients, but preventing peri-implantitis is the success of implant treatment.

• Journal of information and communication convergence engineering
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• v.7 no.2
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• pp.141-147
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• 2009

To initialize and maintain self-organizing networks such as mobile ad hoc networks, address allocation protocol is essentially required. However, centralized approaches that pervasively used in traditional networks are not recommended in this kind of networks since they cannot handle with mobility efficiently. In addition, previous distributed approaches suffer from inefficiency with control overhead caused by duplicated address detection and management of available address pool. In this paper, we propose a new dynamic address allocation scheme, which is based on adaptive partition. An available address is managed in distributed way by multiple agents and partitioned adaptively according to current network environments. Finally, simulation results reveal that a proposed scheme is superior to previous approach in term of address acquisition delay under diverse simulation scenarios.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.653-655
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• 2015

The nodes of Ad-hoc network are made up of location registration for sending informations and a great number of packet transmissions to maintain routing route among the nodes. Under this environment, a huge number of traffics would be generated as mobility variable occurs more than in physical network. Hence, in this paper, focused on to study the relationship of nodes to analyze the extent of the traffic in order to control the traffics of the multi-hop in Ad-hoc.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1313-1316
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• 2005

In the present paper, it was investigated that adhesion layer on gate insulator could affect the electrical characteristics for the organic thin film transistors (OTFTs). The polyimide (PI) as organic adhesion layer was fabricated by using the vapor deposition polymerization (VDP) processing . It was found that electrical characteristics improved comparing OTFTs using adhesion layer to another. We researched adhesion layer as a function of thickness. For inverted-staggered top contact structure, field effect mobility, threshold voltage, and on-off current ratio of OTFTs using adhesion layer of PI 15 nm thickness on the gate insulator with a thickness of 0.2 ${\mu}m$ were about 0.5 $cm^2/Vs$, -0.8 V, and $10^6$, respectively.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.57-63
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• 2005

Development of a locomotive mechanism fer the capsule type endoscopes will largely enhance the ability to diagnose disease of digestive organs. In connection with it, most of researches have focused on an installable locomotive mechanism in the capsule. In this paper, it is introduced that the movement of a capsule type endoscope in digestive organ can be manipulated by magnetic force produced outside human body. Since the magnetic force is provided by permanent magnets, no additional power supply to the capsule is required. Using a robotic manipulator for locating the external magnet, the capsule motion control system can cover the whole human digestive organs. This study is particularly concentrated on dither motion effect to improve the mobility of capsule type endoscope. It was experimentally found out that the friction coefficient between the capsule and digestive organ can be remarkably reduced by superposing yawing or rolling dither motion on the translatory motion. In this paper, the experimental results obtained with the direction, amplitude and frequency of sinusoidal dither motion changed is reported.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.994-999
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• 2007

The particulate matters emitted by diesel locomotives cause serious air pollution in stations and railroad. There have been various attempt to reduce the air pollution from diesel bus or trucks. However, the air pollution from the diesel locomotives has been out of control because there has not any adaptable technology. In this study, a diesel particulate filter was developed and applied to the diesel locomotives. A 3,000 horsepower large-scale locomotive and a 1,500 horsepower middle-scale locomotive were used for the test of the filter. The particulate matter emissions before and after the treatment was monitored by a scanning mobility particle sizer and a dust monitor. As a result, it was observed that the particulate matters could be successfully removed from the emission gases by using the filter.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.828-830
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• 2002

In this study, we have investigated a simple process of preparation of white pigment particles by physical coating with functionalized wax for the electrophoretic display. We will discuss, especially, the implementation of bistable pigment providing high mobility by using unique charge control agent and also optical properties of wax coated $TiO_2$ particles.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7A
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• pp.781-785
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• 2004

Mobile IP maintains Internet connectivity while Mobile Hosts moving from one Internet attachment point to another. However, Mobile If is not appropriate for seamless mobility. Some micromobility protocols were proposed to complement Mobile IP by offering fast and seamless handoff control in limited geographical areas. In this paper, a new scheme, based on path prediction and resource reservation, is proposed to reduce the handoff latency by trying to eliminate the link setup time for fast handoff in all-IP wireless networks. Analytical results show that the proposed scheme offers shorter handoff delay and can improve the handoff efficiency.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.4
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• pp.153-160
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• 2010

MANET composed mobile nodes without central concentration control like base station communicate through multi-hop route among nodes. Accordingly, it is hard to maintain stability of network because topology of network change at any time owing to movement of mobile nodes. MANET has security problems because of node mobility and needs intrusion detection system that can detect attack of malicious nodes. Therefore, system is protected from malicious attack of intruder in this environment and it has to correspond to attack immediately. In this paper, we propose intrusion detection system based on rules in order to more accurate intrusion detection. Cluster head perform role of monitor node to raise monitor efficiency of packet. In order to evaluate performance of proposed method, we used jamming attack, selective forwarding attack, repetition attack.