• Elastomers and Composites
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• v.44 no.1
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• pp.69-75
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• 2009

Asphalt sealants for the crack repair of asphalt concrete road were prepared using waste lubricant oil in this work. The waste lubricant oil was compounded with asphalt(AP-5), SBS triblock copolymer, a tackifying agent(petroleum resin), and antioxidants. Cone penetration, softening point, ductility, elongation by tensile adhesion, and resilience of asphalt sealant compounds were measured. Cone penetration of asphalt sealant compounds increased with the increase of waste lubricant oil content while their softening point, ductility, and resilience decreased. By the addition of talc as an extender, softening point and resilience of asphalt sealants increased, but cone penetration, ductility, and elongation by tensile adhesion of those decreased with the proportion of talc content. The most economic asphalt sealant which could pass an ASTM specification could be manufactured by the big decrement of petroleum resin content.

• Journal of the Korean Society for Railway
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• v.18 no.3
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• pp.186-193
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• 2015

In this paper, a reliability growth analysis for a next-generation high-speed train was conducted. First, the high-speed train was decomposed into 6 sub-systems and main equipment of the high-speed train was derived from functional diagrams. Next, failure rates were calculated for each sub-system from the failure data obtained during commissioning tests. Then, reliability growth analysis was conducted for the high-speed train using the Duane model. The results show that activities to increase reliability were carried out throughout the test runs from the reliability growth results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.415-418
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• 2011

This paper describes a circuit-level optimization of DFU(decoding function unit) for LDPC decoder which is used in wireless communication systems such as WiMAX and WLAN. The conventional DFU which is based on min-sum decoding algorithm needs conversions between two's complement values and sign-magnitude values, resulting in complex hardware. In this paper, a new design of DFU that is based on sign-magnitude arithmetic is proposed to achieve a simplified circuit and high-speed operation.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.6
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• pp.1237-1246
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• 2021

This paper is about Asynchronous Transfer Mode (ATM) cell security in which an Output Feedback (OFB) mode is applied to an AES block ciphers. ATM cells are divided into user data cells and maintenance cells, and each cell is 53 octets in size and consists of a header of 5 octets and a payload of 48 octets. In order to encrypt/decrypt ATM cells, the boundaries of cells must be detected, which is possible using the Header Error Control (HEC) field in the header. After detecting the boundary of the cell, the type of payload is detected using a payload type (PT) code to encrypt only the user cell. In this paper, a security method for ATM cells that satisfies the requirements of ISO 9160 is presented.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.6
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• pp.629-633
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• 2011

Recently, systems such as aircraft, trains and ships have become larger more complex. Therefore, the reliability calculation of these systems is more difficult. This paper presents a reliability calculation algorithm for a complex system with a solution that is difficult to analyze. When the system has a very complex structure, it is very difficult to find an analytical solution. In this case, we can assess system reliability using the failure enumeration method of the reliability path. In this research, we represent the reliability block diagram by an adjacent matrix and define the reliability path. We can find any system status by the failure enumeration of the reliability path, and thus we can calculate any kind of system reliability through this process. This result can be applied to RCM (Reliability-Centered Maintenance) and reliability information-management systems, in which the system reliability is composed of the reliabilities of individual parts.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.466-469
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• 2003

This paper presents the routing and wavelength and timeslot assignment problems for a circuit-switched time division multiplexed (TDM) wavelength-routed networks. In this paper, we propose an efficient distributed control protocol for establishing lightpath dynamically. The protocol uses backward reservation to reduce the chance of blocking. we use aggressive reservation method with usable multiple channels and select only one in multiple channel. We show through simulation that the proposed protocol improves the success rate in TDM -based lightpath establishment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1259-1262
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• 2005

현재 디지털 기술의 핵심인 임베디드 시스템은 2010년 국민소득 2만불 달성이라는 국가 발전 목표의 실현을 위한 핵심 산업으로 2003년 8월 10개 신성장동력 산업의 핵심육성 분야로 선정되었다. 하지만, 특수한 목적을 위한 다양한 임베디드 시스템은 개발 및 유지 보수 비용과 개발 기간이 장기화 됨으로써 시장경쟁력 약화의 원인이 된다. 본 논문에서는 임베디드 시스템의 신뢰성 있는 개발을 위한 방법으로 가상프로토타이핑을 제안한다. 소프트웨어와 하드웨어로 각각 구현될 도메인을 선정하여 플랫폼 라이브러리에 등록되고 통합된 시뮬레이션을 통한 검증을 수행함으로써 제조 공정이 다른 여러 기능의 블록을 집적하는 기술을 가상플랫폼을 기반으로 가상프로토타이핑한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.297-302
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• 1998

최근 원자력산업계 동향은 기기의 노후화, 예비품 확보의 어려움, 그리고 기존 설비에 대한 보수비용 증가 등의 이유로 아날로그 계측제어 설비들을 컴퓨터-기반 설비로의 부분적인 개선이나 전체적인 교체가 추진되고 있다 그러나 컴퓨터-기반 설비는 소프트웨어와 하드웨어가 환경영향에 민감하고, 공통모드고장을 일으킬 수 있는 프로그래밍 설계오류의 잠재성이 있는 것으로 알려져 있다. 공통모드고장을 방지할 수 있는 가장 설득력 있는 해결방안은 철저한 품질보증, 심층방어 및 다양성 설계기법으로 평가되고 있다. 본 논문에서는 컴퓨터-기반 계측제어계통의 심층방어 및 다양성에 관한 규제기준과 정성적 평가를 위한 블록개념을 소개하고, 평가의 사례로서 CE System 80+와 국내 가동중인 W형 원전의 설비개선에서 주급수 상실시 컴퓨터-기반 설비의 공통 모드고장에 따른 다양성과 심층방어계층을 평가하였다. 특히 국내 가동중인 W형 원전에 대해서는 그 평가결과를 근거로 하여 ATWS 완화설비의 설치를 제안하였다.