• Journal of the Korean Institute of Gas
• /
• v.7 no.3 s.20
• /
• pp.58-64
• /
• 2003

This paper presents design safety analysis of pressure vessels. The gas pressure and thermal loads are applied to the pressure vessel simultaneously. In this study, ASME Sec. VIII Div. 2 code was accepted for the safety design of high-pressure vessel. And this result was analyzed using a coupled thermal-mechanical FEM analysis technique. The FEM computed result shows that ASME design code may not guarantee for combined loads of high gas pressure and thermal loads. And solid pressure vessel may be safe compared to other pressure vessels with supporting rings round the cylinder body.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2022.09a
• /
• pp.122-122
• /
• 2022

현재, ‘마약류 관리에 관한 법률’에 의해 규제되고 있는 대마는 “대마초와 그 수지 및 이를 원료로 제조된 제품 일체”에 대한 판매 및 유통이 엄격히 금지되어있다. 예외로, “대마초의 종자·뿌리 및 성숙한 대마초의 줄기와 그 제품”은 규정예외 되어있지만, 이를 식품 및 화장품 등의 산업재료로 활용하기 위해서는 대마의 새싹 및 근경부의 생산량과 안전성이 확보되어야만 한다. 그러므로, 본 연구에서는 동일 생육조건하에 LED광원에 따른 대마(Cannabis sativa L.)의 생육 및 생산량 차이를 확인하였다. 또한, LED광원 별 새싹대마의 독성을 확인하기 위해 대식세포인 RAW 264.7에 추출물을 처리하여 세포독성을 평가하였다. 실험결과, 청색광 처리 새싹대마가 생체 중 12.8 g로 가장 높았다 (적색광 10.8 g, 차광 8.8 g). 광원 별 세포독성은 모든 광원별 새싹대마 추출물에서 0.1 ~ 1 mg/ml까지 농도에서 독성이 없음을 확인하였다. 결과적으로, 빛을 처리한 조건의 새싹대마가 차광된 조건의 새싹대마보다 생산량이 증대되었으며, 광원별 새싹대마에서 세포독성이 없음을 확인하였다. 그러므로, 본 연구를 통해 대마 새싹이 식품 및 산업적 소재로서의 경쟁성과 안전성을 가지고 인체에 유익한 소재로 활용될 수 있는 가능성을 보였다.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.5A
• /
• pp.379-387
• /
• 2011

According to the development of ultra-high performance concrete (UHPC), its mechanical performance have been known as superior than normal and/or high performance concrete. However, its construction and structural safety must have studied with revisions and supplements. In this study, tests have been performed on UHPC precast segment joint with different levels of joint types and lateral forces under direct shear. From the results of the experimental tests, it can be concluded that the properties of the referred joints are significant for the resistance of shear behavior, and the increase of lateral force in these joints may suggest as critical lateral stress on that behavior.

• Science of Emotion and Sensibility
• /
• v.24 no.2
• /
• pp.25-38
• /
• 2021

The aim of this study is to protect workers and pedestrians from accidents at night or bad weather by attaching optical fiber to existing safety clothing that is made only with fluorescent fabrics and retroreflective materials. A safety vest was designed and manufactured by applying optical fiber, and energy-harvesting technology was developed. The safety vest was designed to emit light using the automatic flashing of optical fibers attached to the film, and an energy harvester was manufactured and attached to drive the light emission of the optical fiber more continuously. As a result, first, the vest wearer' body was recognized from a distance through the optical fiber and retroreflection, which helped prevent accidents. Thus, this concept helps in saving lives by preventing accidents during night-time work on the roadside or activities of rescue crew and sports activities, or by quickly finding the point of an accident with a signal that changes the optical fiber light emission. Second, to use the wasted energy, a piezoelectric-element power generation system was developed and the piezoelectric-harvesting device was mounted. Potentially, energy was efficiently produced by activating the effective charging amount of the battery part and charging it auxiliary. In the existing safety vest, detecting the person wearing the vest is almost impossible in the absence of ambient light. However, in this study, the wearer could be found within 100 m by the light emission from the safety vest even with no ambient light. Therefore, in this study, we will help in preventing and reducing accidents by developing smart safety clothing using optical fiber and energy harvester attached to save lives.

• Tunnel and Underground Space
• /
• v.28 no.3
• /
• pp.258-276
• /
• 2018

The accurate and quantitative ground information on the hydraulic conductivity characteristics of rock mass is one of the key factors for evaluation of the hydro-geological behaviour of rock mass around an excavated opening under high water pressure. For tunnel and rock structures in seabed, where the sea acts as an infinite source of water, its importance become greater with increasing construction depth below sea level. In this study, to improve the problems related with poor system configuration and incorrect data acquisition of previous hydraulic packer testing equipment, we newly developed an integrated main frame and 30 bar level waterproof downhole sonde apparatus, which were optimized for deep hydraulic packer test in seabed rock mass. Integration of individual test equipment into one frame allows safe and efficient field testing work on a narrow offshore drilling platform. For the integrated type main frame, it is possible to make precise stepwise control of downhole net injection pressure at intervals of $2.0kg_f/cm^2$ or less with dual hydraulic oil volume controller. To ensure the system performance and the operational stability of the prototype mainframe and downhole sonde apparatus, the field feasibility tests were completed in two research boreholes, and using the developed apparatus, the REV(Representative Elementary Volume) scale deep hydraulic packer tests were successfully carried out at a borehole located in the basalt region, Jeju. In this paper, the characteristics of the new testing apparatus are briefly introduced and also some results from the laboratory and in-situ performance tests are shown.

• Journal of the Korean Institute of Gas
• /
• v.26 no.1
• /
• pp.34-40
• /
• 2022

Gas cylinder cabinets have risks such as cylinder explosion and scattering of debris when a fire occurs. These risks are likely to cause gas spills and cause secondary damage. In order to reduce damage, it is very important to secure the fire resistance performance of the gas cylinder cabinet. In foreign countries, NFPA codes in the United States and EN-14470-2 in Europe stipulate fire resistance test standards for gas cylinder cabinets to protect internal cylinders for a certain period of time in a situation where gas cylinder cabinets are exposed to flames. However, in Korea, only internal pressure performance and airtight performance standards are specified, and the target is limited to piping, and research and regulations for the fire resistance performance of gas cylinder cabinets are insufficient compared to overseas. Therefore, in this study, finite element analysis was used to establish fire resistance standards for domestic gas cylinder cabinets. In the event of a fire, optimal conditions are derived in terms of structure and material.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.5
• /
• pp.1-8
• /
• 2013

This paper implements an integrated vehicle chassis system of ACC(Adaptive Cruise Control) and LKS(Lane Keeping System) based on OSEK OS to vehicle operating system and analyzes its performance through experiments. In recent years active safety and advanced driver assistance system has discussed to improve safety of vehicle. Among the rest, We integrate ACC that controls longitudinal velocity of vehicle and LKS that assists a vehicle in maintaing its driving lane, then implement integrated control system in vehicle. Implemented control system uses OSEK/VDX proposed standard, which is aiming at reusability and safety of software for vehicle and removal hardware dependence of application software. Redesigned control system based on OSEK OS, which is supported by OSEK/VDX, can manage real-time task, process interrupt and manage shared resource. We show by results performed EILS(ECU-In-the-Loop Simulation) that OSEK OS-based integrated controller of ACC and LKS is equivalent conventional integrated controller of ACC and LKS.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2004.05a
• /
• pp.5-8
• /
• 2004

컴퓨터기반 운전지원시스템은 운전원의 발전소 상태감시와 진단기능을 수행을 지원하여 운전원의 안전성을 향상시키는 시스템으로 80년대 중반부터 개발되어왔고, 또한 최근의 컴퓨터 기술과 도구의 빠른 발전으로 컴퓨터기반 운전지원 시스템의 개발 및 원전 적용에 대한 연구가 이루어지고 있다. 본 논문에서는 컴퓨터기반 운전원 조언 시스템의 기술 현황을 분석하고, 현재 설계를 진행중인 일체형원자로(SMART, System-integrated Modular Advanced ReacTor)에 컴퓨터기반 운전지원 시스템 적용을 위한 개발방안을 제안한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04b
• /
• pp.394-396
• /
• 2004

원자력 산업계에서는 원전 MMIS(Man-Machine Interface System)의 디지털 기술 적용을 위해 많은 노력을 기울이고 있고, 특히 원자력 산업의 특수성인 안전성 확보에 필요한 개발기준과 규제방법 정립에 많은 연구가 수행되고 있다. 또한 디지털 MMIS의 핵심기반기술인 고 신뢰도 소프트웨어 개발 방법론이 확립되지 못하여 소프트웨어 공통모드고장 문제, 정량적인 소프트웨어 신뢰도 보장 문제 등이 현안으로 제기되고 있다. 이와 같이 원전 MMIS의 디지털화를 성공하기 위해서는 소프트웨어의 고 신뢰도 확보가 관건이며, 고 신뢰도를 확보하기 위한 소프트웨어 개발 방법론의 정립이 절실히 요구되고 있다. 본 논문에서는 원전 소프트웨어 개발에 적응되는 규제지침을 분석하고, 일체형원자로(SMART, System-integrated Modular Advanced ReacTor) MMIS 소프트웨어 개발에 적응될 소프트웨어 개발 방법론을 제시한다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.11
• /
• pp.604-609
• /
• 2016

This study evaluated the long-term performance of RSR (Reinforced Subgrade for Railways) technology which increases the railway line capacity without the need for additional land. Its characteristics include the use of a short reinforcement with rigid wall, which make it possible to apply it in confined spaces. The 7m high and 40m long testbed employed to evaluate the long-term performance was designed and constructed near Jupo station on the Chang-hang line. This line, located close to a local bus route, had collapsed at the subgrade following heavy rainfall. The performance of the new type of subgrade was verified with long term measurements over a 2 year period including the surface and ground settlement, horizontal displacement of the wall, tensile strain of the reinforcement, and settlement of the rail top on the side track. Based on the results of the measurements made until now, we concluded that it had sufficient safety and serviceability for use as a railway subgrade. It is expected that RSR technology could be frequently used at sites which lack the necessary construction materials for an embankment and are located close to functional railway lines and boundaries, in order to settle civil complaints.