• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.5
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• pp.422-428
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• 2013

Recently, many unmanned aerial vehicle (UAV) studies have focused on small UAVs, because they are cost effective and suitable in dangerous indoor environments where human entry is limited. Map building through distance measurement is a key technology for the autonomous flight of small UAVs. In many researches for unmanned systems, distance could be measured by using laser range finders or stereo vision sensors. Even though a laser range finder provides accurate distance measurements, it has a disadvantage of high cost. Calculating the distance using a stereo vision sensor is straightforward. However, the sensor is large and heavy, which is not suitable for small UAVs with limited payload. This paper suggests a low-cost distance measurement system using a laser pointer and a monocular vision sensor. A method to measure distance using the suggested system is explained and some experiments on map building are conducted with these distance measurements. The experimental results are compared to the actual data and the reliability of the suggested system is verified.

• Journal of Korean Society of Transportation
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• v.32 no.5
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• pp.513-521
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• 2014

Korea's traffic congestion costs including other social costs due to accidents, environmental pollution and increased demand is increasing every year. In this regard, direction of government policy was geared toward suppression of vehicle demand and activation of public transportation, which is determined to be the best solution with limited supply of infrastructure such as road facilities. This study aims to implement public transport bus-only Head-Up Display (hereafter called HUD) technology which displays public transport information required for a bus driver on the front glass of a bus. The public transport bus-only HUD not only prevents gaze dispersion of bus drivers but also helps to reduce the heavy workload of bus drivers by providing information required for driving. Ultimately, the final research purpose is a reduction of bus traffic accidents by 50% caused by negligence in keeping eyes forward or sideways.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.284-290
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• 2009

As the increased importance is placed on the new transit systems owing to the environmental pollution caused by the road traffic congestion, the policy for the introduction of the new transit systems as an alternative solution to ease the heavy burden of the construction expenses is being actively established. Since the explicit recognition of such transit systems and the review on the method of its adoption have been a pressing matter in the light of reducing the pending traffic congestion, the development of the rolling stock systems in modes of new transportation has been made in various ways taking into consideration the regional circumstances to alleviate traffic congestion, and offer a more efficient service with the application of their intrinsic characteristics. Such systems also have been developed as a mix of punctuality for railway systems operating on the runway and flexibility for buses. This paper, therefore, deals in more detail with 3 modes of systems such as low-floor articulated buses, GRT(Guided Rapid Transit) and tram cars, and studies the overseas cases of the operation of those systems involving both negative and positive aspects.

• Journal of the Korean Institute of Gas
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• v.15 no.2
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• pp.21-26
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• 2011

Emissoin of heavy duty vehicle have much positioned in air pollution although its limited number of vehicles. CNG vehicles are coming to the fore as one of the solution of diesel vehicles. CNG vehicles exhaust smaller emission than diesel vehicles on PM and NOx. In this study, aftertreatment technologies are introduced on vehicles which use CNG and hydrogenmixed fuel. Withmixing hydrogen with CNG, combustion efficiency is enhanced, and harmful emission might be decreased, but methane that is main component of CNG brings green house effect. In order to remove methane and NOx in exhaust gas of CNG engine, methane oxidation catalyst and SCR technologies were respectively analyzed.

• Journal of the Korea Institute of Building Construction
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• v.16 no.4
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• pp.381-388
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• 2016

The snow control storage facilities have the physical requirements that are an anti-icing and deicing operations. They are efficiently and quickly performed, and composed of a vehicle depot for the snow removal equipment and truck, anti-icing and deicing chemical storages, and the control utilities. This study is to investigate the planning guidance of foreign countries, and the actual conditions of the snow control chemical storage facilities for expressway, the national highway and the local road, and is to suggest the planning guidelines. As some of the authorities have no fixed structures for the snow control storage, this study analyze the 5 cases constructed lately. From the result of the case studies, the operations performed in the snow control storage facilities and drawback of the facilities are analyzed with respect to layout, size, plan, and structure, and the improvement planning guidance is also suggested.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.597-603
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• 2014

The cargo of ships and offshore structures is the number of oil of combustibility and volatile, oil processing cargo. Furthermore heavy cargo of the vehicle or container box or bulk cargo are occupied the remainder of cargo. In addition, there is a possibility to move the location of the cargo and the vessel because it is received periodic / non-periodic a load of wave and ocean current. Therefore a shipboard hazard is much greater than onshore industry hazard. Monitoring and preparation for safety are necessary things because there is always risk of accidents arise from the impact of the freight and cargo of ships and offshore structures. In this study, we conducted a study with respect to the introduction of the wireless sensor network monitoring system to ensure the safety of the crew and workers on shipboard.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.1
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• pp.37-43
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• 2002

Recently, the construction of tunnels longer than one kilometer has increased rapidly. Considering characteristic of limiting structure of longer tunnel, if fires inside tunnel broke out because of vehicle incidents, the catastroph would have high possibility to take place due to toxic smoke and heat of fire. In case of highway tunnel, safety facilities which can cope with tunnel fire are installed in the tunnel but according to rapid increase of heavy good traffic, dangerous goods and enlargement of tunnel magnitude, the research has to carry out about heat fluxes and smoke behaviour during tunnel fire. Therefore, through full-sized fire experiment the paper analyzed temperature distribution, wind velocity, smoke behaviour during tunnel fire.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2025-2027
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• 2003

미끄럼방지 제동장치는 차량의 급제동 시 바퀴의 장김을 방지하여, 바퀴의 슬립을 최적으로 유지 시킴으로써 제동거리를 단축시키고, 운전자가 차량 조향성을 유지할 수 있게 만드는 차량 안정장치이다. 이 장치는 비행기의 착륙거리를 줄이기 위해 개발된 이래로, 철도 및 차량 등에도 널리 적용되고 있으며, 국내에서도 이미 승용차를 위주로 양산되고 있는 추세이다. 이러한 미끄럼방지 제동 장치는 공압 브레이크 장치를 사용하는 대형차량 분야에서는 아직 국내에서 적용된 사례가 없었으나, 지난 3 년간의 연구개발의 성과로 대형 버스에 적용 가능한 미끄럼방지 제동장치의 전자제어기가 개발 완료되었으며, 국제 규격을 바탕으로 국내 현실에 적합한 미끄럼방지 제동장치 장착 대형차량의 시험 규격을 정하여 이 규격에 의거 제동시험을 실시하고 개발 제어기의 성능을 평가하였다. 각 제동 시험은 $\mu$-Jump 제동시험 및 Split-$\mu$ 제동시험 등의 직진 주행 중 급제동시험, 급제동 중 차선변경 시험, 장애물 회피 제동시험 등을 포괄하며 국제적인 규격을 기준으로 정한 독자 규격을 만족하였다. 본 논문에서는 공압 브레이크를 장착한 대형차량의 미끄럼방지 제동장치의 제동성능평가 시험방법을 소개하고, 이 방법에 의해 성능평가 시스템 및 측정 시스템을 구성하여, 개발 전자제어기의 우수성을 확인하였으며, 그 측정결과의 일부를 제시하였다.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.146-153
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• 2013

CNG buses has contributed to improve air quality in cities. But it is difficult to meet the next emission regulations such as EURO-VI without the help of additional post-processing device. Hydorgen has higher flame speed and lower combustion temperature that make it thermal efficiency increase with leaner operation. Using hydrogen natural gas blend (HCNG) fuel is promising technology which can reduce $NO_x$ and $CO_2$ emissions for a natural gas vehicle. However, fuel flow rate of HCNG should be increased since hydrogen's energy density per volume is much smaller than natural gas. In the present study, the characteristics of fuel supply system and its applicability were evaluated in a heavy duty natural gas engine. The results showed that the potential of fuel pressure regulator and fuel metering valve had enough capacity with HCNG. Employed mixer did not affect the distribution characteristics of mixture.

• Journal of the Korean Institute of Gas
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• v.13 no.6
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• pp.39-43
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• 2009

Gasoline engine have proved its utility in light, medium and heavy duty vehicle in every sector of the world community. The concern about long term availability of petroleum and the increasing threat for the environment by the increasing load of vehicular emission, compel the technology to upgrade itself for meeting the challenges. CNG is environmentally clean alternative to the existing SI Engines with out much change in the hardware. Many researchers have found this as a potential substitute to meet the energy requirement. Higher octane number and higher self ignition temperature make it a good gaseous fuel. Although power output is slightly lesser than the gasoline it's thermal efficiency is better than the gasoline for the same SI Engine. Results showed that reduced CO, hydrocarbon emissions is a favorable outcome, with slight increase in NOx emission when compared with gasoline fuel to dual fuel mode in the existing SI Engines.