• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.3
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• pp.263-269
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• 2003

Magnetic flux leakage (MFL) signals were used for corrosion inspection of buried oil and gas pipeline. 3D finite element analysis was used to examine the effects of far and near-side pit depth and tensile stress on MFL signals. Anisotropci materials were used, and the effects of simulated tensile stress on MFL were investigated. The axial and radial MFL signals depended on far and near-side single pit depth and on the bulk stress, but the circumferential MFL signal did not depend on them. The axial and radial MFL signals increased with increasing pit depth and the bulk stress, but the circumferential MFL signal was scarcely changed.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.947-953
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• 2005

Previous test results showed that the current ASTM(American Standard for Testing and Materials) grip adapter for GFRP(Glass Fiber Reinforced Polymer) rebar was not fully successful in developing the design tensile strength of GFRP rebars with reasonable accuracy. It is because the current ASTM grip adapter which is composed of a pair of rectangular metal blocks of which inner faces are grooved along the longitudinal direction does not take into account the various geometric characteristics of GFRP rebar such as surface treatment, shape of bar cross section as well as physical characteristics such as poisson effect, elastic modulus in the transverse direction and so on. The objective of this paper is to provide how to proportion the optimum diameter of inner groove in ASTM grip adapter to develop design tensile strength of GFRP rebar. The proportioning of inner groove in ASTM grip adapter is based on the force equilibrium of GFRP rebar between tensile capacity and minimum frictional resistance required along the grip adapter. The frictional resistance of grip adapter is calculated based on the compressive strain compatibility in radial direction induced by the difference between diameter of GFRP rebar and inner groove In ASTM grip. All testing procedures were made according to the CSA S806-02 recommendations. From the preliminary test results on round-type GFRP rebars, it was found that maximum tensile loads acquired under the same testing conditions is highly affected by the diameter of inner groove in ASTM grip adapter. The grip adapter with specific dimension proportioned by proposed method recorded the highest tensile strength among them.

• 한국정보통신설비학회:학술대회논문집
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• 2006.08a
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• pp.134-140
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• 2006

홈 게이트웨이가 가져야 하는 기능에 대한 요구사항을 분석하고 통신사업자의 관점에서, QoS 기능과 IP 주소변환 기능을 중심으로 세부적인 스위칭 칩의 기능과 성능을 규정하였다. QoS 기능, 패킷 필터링 기능, 그리고 IPv6 주소체계 도입 등과 같이 급변하는 네트워크의 요구사항을 유연하게 수용하여, 칩의 기능과 성능을 수정하거나 추가할 수 있도록 패킷프로세서 기반으로 스위칭 칩을 설계하였으며, 홈 게이트웨이의 구성을 단순화하기 위해 스위칭 칩의 패킷 메모리와 룩업 메모리를 칩 내부에 내장하였다. 그리고 칩의 설계를 검증하기 위해 FPGA를 이용하여 6포트 스위칭 칩으로 구현하여 기능 및 성능시험을 수행하였다. NAT, Flow에 따른 패킷 분류 및 패킷 변경, SPQ, DWRR과 같은 스케줄링 등의 시험을 통하여 설계한 칩의 기능과 성능을 확인하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.761-764
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• 2007

UPnP AV(Universal Plug & Play Audio/Video)는 홈 네트워크에서 UPnP 기술을 이용하여 비디오나 오디오 등과 같은 멀티미디어를 재생하고 분배하거나 혹은 공유하는데 필요한 표준통신규약이다. 웹 서비스 기술은 서로 다른 플랫폼상에 존재하는 서비스를 통합하기 위한 표준이다. 본 논문에서는 홈네트워크에서 UPnP AV 아키텍처를 사용해서 다양한 플랫폼을 가진 디바이스에 존재하는 미디어 서비스들을 통합하기 위한 시스템을 어떻게 설계하고 구현 했는지에 대해 기술한다. 제안한 시스템은 미디어의 저장과 재생을 동적으로 선택하고 제어하기 위해 UPnP AV 의 미디어서버(Media Server)와 렌더러(Renderer) 그리고 컨트롤 포인트(Control Point) 모델을 구현하고 있다. 또한, PDA와 같은 다양한 플랫폼을 가지고 있는 디바이스들을 통해 홈 네트워크 외부에서 홈 네트워크 내부에 존재하는 미디어 서비스들을 제어하기 위해 웹 서비스 기술을 사용하고 있다.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.4
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• pp.505-509
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• 2011

Home network system makes it available for controlling inside home and for controlling from outside as well with personal computer, cellular phone or smart phone, by connecting diverse information equipments within home such as lighting, gas, and heating equipments with network. Integrated server and wall-pad, which form home network system, have demerits as saying of being high-priced and of needing to implement network infrastructure. This study suggested the intelligent home network system, which uses smart phone of supplementing these merits of home network system. It substituted high-specification input & output equipment in the currently and widely supplied smart phone for display and touch screen, which are user interface part of the existing wall-pad, and implemented the common wall-pad with low cost by concentrating management and control function of home network on smart phone.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.493-496
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• 2002

홈 네트워크의 문제점인 IP 부족 문제와 부가 서비스(디지털 컨텐츠의 지능형 서비스, 서비스 번들 지원 등) 제공의 한계성을 극복하기 위해 Service Server for Residential Gateway(SSRG)를 제안한다. SSRG는 단독주택뿐만 아니라 대규모 아파트 단지 혹은 주택단지에 개별적으로 설치된 RG를 통합 관리하는 서버로서 홈 네트워크 및 내부 네트워크에 로컬 IP를 부여하고 RG와 SSRG를 NAT(Network Address Translator)를 통하여 제어함으로써 P의 문제를 해결함과 동시에 각 홈 네트워크와 RG의 기능을 확대하고 보다 많은 부가 서비스를 제공할 수 있도록 구현하였다. 제안된 SSRG는 가정 내에 보다 확장된 서비스와 기기 관리를 위한 통로 제공, RG 및 각종 기기들의 소프트웨어 업그레이드 및 기기 상태점검이 가능하고, 또한 사설 IP 상에서도 기기들을 외부에서 액세스 할 수 있고 각종 서버를 하나의 단지 혹은 논리적으로 구분되는 하나의 서브 넷에 두게 됨으로써 관리 및 향후 보수가 용이한 장점이 있다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.5
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• pp.109-119
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• 2004

The home network environment can be defined as a network environment, connecting digital home devices such as computer systems, digital appliances, and mobile devices. In this kind of home network environments, there will be numerous local/remote interactions to monitor and control the home network devices and the home gateway. Such an environment may result in communication bottleneck. By applying the mobile agents that can migrate among the computing devices autonomously and work on behalf of the user, remote interactions and network traffics can be reduced enormously. The mobile agent authentication is necessary to apply mobile agent concept to the home network environments, as a prerequisite technology for authorization or access control to the home network devices and resources. The existing mobile agent systems have mainly used the public key based authentication scheme, which is not suitable to the home network environments, composed of digital devices of limited computation capability. In this paper, we propose a shared key based mobile agent authentication scheme for single home domain and expand the scheme to multiple domain environments with the public key based authentication scheme. Application of the shared key encryption scheme to the single domain mobile agent authentication enables to authenticate the mobile agent with less overhead than the public key based authentication scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.4B
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• pp.191-199
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• 2007

Mobile node has to register its current location to Home Agent when it moves to another network while away from home. However, the registration procedure cannot be completed successfully when Home Agent is protected by the VPN gateway which guards MN's home network and discards the unauthorized packets incoming from outside as a lack of security association(SA) between the Care-of address and security policy of the home network so that the binding registration message without SA is discarded smoothly by the VPN gateway. This paper presents the authentication and key exchange scheme using the AAA infrastructure for a user in Internet to access the home network behind the VPN gateway. By defining the role of authentication and tunnel processing for each agent or relay entity, this paper presents the procedure to register the current location to its Home Agent with secure manner. Performance result shows cost improvement up to 40% comparing with existing scheme in terms of the packet loss cost, the property of mobility and traffic.

• 정보화사회
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• s.161
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• pp.11-17
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• 2003

홈네트워크 기술은 고속의 인터넷 통신 및 디지털 가전기기를 수용할 수 있는 새로운 개념의 댁내 통신 기반을 지칭하는 용어로 가정 내부의 통신 기반을 개선하기 위한 기술이다.

• Journal of Internet of Things and Convergence
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• v.1 no.1
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• pp.21-25
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• 2015

The Internet of Thing (IoT) will be a very important core technology to implement Intelligent Smart Home Network and it will take charge of an important role connected to Smart Phone, Cloud Computing in the Ubiquitous environment. In this paper, Internal Autonomous Regulation by human autonomic nervous system was studied and its core mechanism was applied to the design of IoT based Autonomous Regulation System for Intelligent Smart Home Network. We proposed an autonomous regulating mechanism in which the factors of Temperature, Humidity and Illumination are automatically adjusted as they communicate with the connected things.