• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.2
• /
• pp.393-404
• /
• 2018

The tunnel can be planned to connect to underground roadway and surface road. The large tunnel and branch section are made when the ramp tunnel access to the main tunnel. In the branch section, stress concentration can be assigned and it can be very important for the stability of the tunnel. This study assessed the behavior of rock pillar in double deck tunnel diverging area by using a two dimensional numerical analysis. This study evaluated different safety factors according to pillar width and the ramp tunnel position in branch. By the assessment of the strength-stress ratio, tunnel pillar width is suggested in order to secure the safety factor 1.5.

• Journal of Korean Society of Transportation
• /
• v.28 no.3
• /
• pp.29-37
• /
• 2010

Ramp metering control is the most representative strategy of uninterrupted flow control and management system. Ramp metering is to adjust vehicles entering an expressway in such a way that expressway mainline maintains flow stability by regulating ramp vehicles. The effect of two metering strategies, single-entry metering and platoon metering, on mainstream under the same metering rate with pre-timed metering are analyzed by micro-simulation. Platoon metering shows lower performance than single-entry metering under the same metering rate in terms of speed, density, and delay, causes earlier breakdown than single-entry metering. It indicates that the selection of metering type has critical importance as the flow of mainline is high.

• Journal of Korean Society of Transportation
• /
• v.26 no.6
• /
• pp.81-89
• /
• 2008

This paper aims to develop an integrated urban freeway exit-intersection actuated traffic signal control strategy based on which a real-time detection of queue at each of an exit-ramp and an arterial. To evaluate effects of the proposed actuated traffic signal control according to various traffic situations and geometric conditions, this paper analyzed the effects of the proposed traffic signal control strategy according to traffic situations such as the occasion of the arterial being saturated, the occasion of the exit-ramp being saturated, and the occasion of both the arterial and the exit-ramp being saturated. To reflect geometric conditions that influence the effects of the control strategy, this paper evaluated effects before and after applying the actuated traffic signal control strategy according to six cases for both above and under the downstream link length of 200m as proposed by COSMOS. The study results shown that when the link length above 200m, offered a greater effect of applying the actuated traffic control strategy than below 200m. Thus, the actuated traffic signal control through a real-time detection of queue is expected to offer a greater effect at longer downward link.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.65-68
• /
• 2007

고속국도 및 일반국도 인터체인지부의 설계속도를 분석하기 위하여 현재 적용되고 있는 국내의 설계기준 즉, 도로의 구조 시설기준에 관한 규칙 및 도로설계편람, 도로설계요령, 도로설계기준, 국도설계기준을 검토하고, 국외의 설계기준을 참고하여 국내기준과 비교 검토하였다. 고속도로 교통사고 통계(2006)를 통하여 사고 다발지점을 선정, 원인을 분석하고 램프 유형별, 허용속도별 전국의 입체교차로를 대상으로 주행속도를 계측하였으며, 그 결과로부터 입체교차로의 Loop Ramp 접속부의 적정 설계속도를 제안하였다.

• Proceedings of the KIPE Conference
• /
• 2017.07a
• /
• pp.196-197
• /
• 2017

최근 국내 태양광산업은 보급량이 증가하고 있고, 정부 정책에서도 에너지신산업을 추진하는 등 시장 활성화에 노력하고 있다. 본교에서는 신재생에너지원 중 태양광발전시스템에 대해 건학이념인 실사구시에 입각한 학부 교육 프로그램을 개발 및 적용하고 있으며 본 논문에서는 이에 대한 내용을 소개한다. 산업체 실무에 기초한 태양광발전시스템 학부 교육 프로그램은 마이크로콘트롤러(MCU) 교육, DC-DC 컨버터와 DC-AC 인버터 등 전력변환장치 기반의 Solar Explorer Kit 교육, 태양광발전시스템 발전량 산출과 손실분석 등 성능평가를 위한 PVsyst 엔지니어링 교육 내용으로 구성된다. 특히, 전력변환장치로 구성된 Solar Explorer Kit 교육 프로그램은 DC-DC 컨버터와 배터리(리튬-폴리머) 충전, 배터리(리튬-폴리머) 방전과 DC LED 부하 접속, 독립형 DC-AC 인버터 출력과 AC 할로겐 램프 부하 접속, 계통연계형 DC-AC 인버터 출력 실습 등에 대해 소개한다.

• Journal of Korean Port Research
• /
• v.14 no.2
• /
• pp.175-185
• /
• 2000

Today freeway is experiencing a severe congestion with incoming or outgoing traffic through freeway ramps during the peak periods. Thus, the purpose of this study is to identify the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the delay predictive models on the rap junctions of freeway with 70mph speed limit. From the traffic analyses, and model construction and verification for delay prediction on the ramp junctions of freeway, the following results were obtained : ⅰ) Traffic flow showed a big difference depending on the time periods. Especially, more traffic flows were concentrated on the freeway junctions in the morning peak period. ⅱ) The occupancy also showed a big difference depending on the time periods, and the downstream occupancy(Od) was especially shown to have a higher explanatory power for the delay predictive model construction on the ramp junctions of freeway. ⅲ) The delay-occupancy curve showed a remarkable shift based on the occupancies observed : O$\_$d/〈9% and O$\_$d/$\geq$9%. Especially, volume and occupancy were shown to be highly explanatory for delay prediction on the ramp junctions of freeway under O$\_$d/$\geq$9%, but lowly for delay prediction on the ramp junctions of freeway under O$\_$d/〈9%. Rather, the driver characteristics or transportation conditions around the freeway were thought to be a little higher explanatory for the delay prediction under O$\_$d/〈9%. ⅳ) Integrated delay predictive models showed a higher explanatory power in the morning peak period, but a lower explanatory power in the non-peak periods.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 1999.10a
• /
• pp.131-140
• /
• 1999

Today freeway is experiencing a severe congestion with incoming or outgoing traffic through freeway ramps during the peak periods. Thus, the objectives of this study is to identify the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the delay predictive models on the ramp junctions of freeway with 70mph speed limit. From the traffic analyses, and model constructions and verifications for delay prediction on the ramp junctions of freeway, the following results were obtained: ⅰ) Traffic flow showed a big difference depending on the time periods. Especially, more traffic flows were concentrated on the freeway junctions in the morning peak period when compared with the afternoon peak period. ⅱ) The occupancy also showed a big difference depending on the time periods, and the downstream occupancy(Od) was especially shown to have a higher explanatory power for the delay predictive model construction on the ramp junction of freeway. ⅲ) The speed-occupancy curve showed a remarkable shift based on the occupancies observed ; Od < 9% and Od$\geq$9%. Especially, volume and occupancy were shown to be highly explanatory for delay prediction on the ramp junctions of freeway under Od$\geq$9%, but lowly for delay predicion on the ramp junctions of freeway under Od<9%. Rather, the driver characteristics or transportation conditions around the freeway were through to be a little higher explanatory for the delay perdiction under Od<9%. ⅳ) Integrated delay predictive models showed a higher explanatory power in the morning peak period, but a lower explanatory power in the non-peak periods.