• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.10-13
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• 2010

The flow field in road tunnel is influenced by some facts such as piston effect of vehicle's move, operation of ventilation facilities, natural wind and buoyancy effect of fire plume. Among those, jet fan is one of main ventilation facilities especially in longitudinal ventilation system of tunnel. In this study to analyze tunnel flow induced by operation of jet fan, numerical simulation has been carried out. The velocity distributions and streamlines in tunnel are examined to consider the three-dimensional characteristics of tunnel flow caused by jet fan.

• 한국도로학회논문집
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• 제18권3호
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• pp.67-74
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• 2016

PURPOSES : This study evaluated the field applicability and laboratory performance of glass fiber-reinforced asphalt (GFRA) mixtures. METHODS : The general hot-mix asphalt (HMA) and GFRA mixtures were paved in five sites, including three national highways, one express highway, and an arterial road, to evaluate field applicability and durability. The plant mixing and construction method for the GFRA were similar to those for the general HMA. The lab performances of the field samples were relatively compared through the mechanical measures from the Marshall stability, indirect tensile strength, and dynamic stability. The field performance was surveyed after a year. RESULTS : The lab tests verified the superior lab performances of the GFRA compared to the general HMA. The Marshall stability of the GFRA increased for about 128% of the general HMA. The indirect tensile strength of the GFRA was 115% greater than that of the general HMA. The dynamic stability of the GFRA resulted in 16,180 reps/mm, which indicated that high rut resistance may be expected. No noticeable defects, such as cracks or deformation, were observed for the GFRA sections after a year. CONCLUSIONS : The lab tests and field survey for the five GFRA sites resulted in superior performances compared to the general HMA. The relatively low-cost GFRA, which required no pre-processing procedures, such as polymer modification, may be a promising alternative to the polymer-modified asphalt mixtures. The long-term performance will be verified by the superior field durability of the GFRA in the near future.

• 한국도로학회논문집
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• 제14권4호
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• pp.125-131
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• 2012

PURPOSES : Road lighting facilities increase the visibility of road at night in order to improve traffic driver safety and comfort. Generally speaking, current pole lighting has a tendency to create problems of glare and flicker. The phenomenon of glare gives discomfort due to increase of scattered light, when high luminance is in driver's field of view. The phenomenon of flicker occurs due to the driver passing through discontinuous pockets of pole lighting areas. These phenomenon increase eye strain and decrease driver safety. METHODS : Low height line lighting that distributes light lower than driver's eye level has been developed and evaluated to reduce the problems linked to current pole lighting. A test was undertaken with 4 conditions(turn on the general pole lighting, turn off alternate pole lighting, turn on the line lighting and line lighting with 50% dimming). A driver written survey was conducted in order to gain driver feedback. RESULTS : Pupil size and brow frequency compared with degree in pole lighting are reduced. CONCLUSIONS : Low height line lighting environment makes drivers more comfortable than pole lighting environment and is positive lighting method in the energy saving and landscape aspect.

• 한국재난정보학회 논문집
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• 제13권2호
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• pp.191-198
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• 2017

레고식 차도블록 시스템은 시설물의 설치 및 유지보수를 위한 도로굴착공사지에서 조립된 구조블록을 사용한 임시포장면을 형성하여 차량 및 보행자의 안전한 통행이 가능하도록 개발된 시스템이다. 레고식 차도블록 시스템의 재료적 품질시험, 미끄럼저항시험 및 압축시험을 통해 기초성능에 대한 연구를 수행하였으며, 현장시험을 통해 레고식 차도블록 시스템의 도로지반 다짐성능을 검토하고 평가하였다. 그 결과, 도로복구를 위한 레고식 차도블록 시스템의 성능 및 다짐 효과는 우수한 것으로 나타났다.

• 한국건설관리학회논문집
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• 제5권4호
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• pp.139-146
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• 2004

Resent removal work for road signs has been labor intensive and required times since it has been done manually using shaving type equipment. While traditional process is conducting, there are traffic jams caused by the passing control, and happened unexpected accidents to workers working at dangerous road circumstance. Besides, in current shaving method, there are high potentialities on the air pollution as well as the explosive accident occurred by using a propane gas. So, as an alternative, we have studied to develop the automatic erasing equipment made up with a high pressure water-jet system and automatic control system, mobile system; Wate-rjet system consists of an intensifier and nozzles to give a high pressure and spray on the sign, and automatic control system is composed of one axis robot using a hydraulic servo actuator controlled by a lever, And as a mobile system, a truck plays an important role for the transport of equipment and the forward movement in a removal process. In this paper, we have analyzed the characteristics of road signs and have investigated current erasing methods in the field. And we have organized and designed automatic erasing equipment, and we have made a basic experiment to find out the optimal spray condition as like the spray distance, spray angle and injection pressure.

• Smart Structures and Systems
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• 제24권6호
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• pp.745-757
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• 2019

Road surface deteriorations such as potholes have caused motorists heavy monetary damages every year. However, effective road condition monitoring has been a continuing challenge to road owners. Depth cameras have a small field of view and can be easily affected by vehicle bouncing. Traditional image processing methods based on algorithms such as segmentation cannot adapt to varying environmental and camera scenarios. In recent years, novel object detection methods based on deep learning algorithms have produced good results in detecting typical objects, such as faces, vehicles, structures and more, even in scenarios with changing object distances, camera angles, lighting conditions, etc. Therefore, in this study, a Deep Learning Pothole Detector (DLPD) based on the deep region-based convolutional neural network is proposed for autonomous detection of potholes from images. About 900 images with potholes and road surface conditions are collected and divided into training and testing data. Parameters of the network in the DLPD are calibrated based on sensitivity tests. Then, the calibrated DLPD is trained by the training data and applied to the 215 testing images to evaluate its performance. It is demonstrated that potholes can be automatically detected with high average precision over 93%. Potholes can be differentiated from manholes by training and applying a manhole-pothole classifier which is constructed using the convolutional neural network layers in DLPD. Repeated detection of the same potholes can be prevented through feature matching of the newly detected pothole with previously detected potholes within a small region.

• 수완나부미
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• 제15권2호
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• pp.57-90
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• 2023

China launched the Digital Silk Road (DSR) in 2015 as part of the existing Belt and Road Initiative (BRI) to expand its influence in digital and technological development across Asia, Europe, and Africa. Southeast Asia is one of the key targets of the Digital Silk Road due to its geographical proximity to China and the rapid growth of the digital sphere. Although the DSR opens several potential opportunities for the Association of Southeast Asian Nations (ASEAN) member states to foster the digitalization process in the region, how each country reacts to projects under the DSR is varied. Secondly, Vietnam is the only ASEAN member state that has not signed any official agreement under the BRI framework, and thirdly, Vietnam opted out of Huawei technology. This paper aims to understand the perspective of Vietnam and how Vietnam has responded to the growing technological presence of China in Southeast Asia until 2021. By using qualitative methods, the author argues that the DSR has allowed Beijing to overcome the limitations of the original strategy, BRI, and strengthen its influence in the field of information and communication technologies, particularly fifth-generation (5G) telecommunications. Furthermore, the paper examines Vietnam's digital development and digital diplomacy and how the Vietnamese government has responded to DSR projects. In light of both the potential threats and economic benefits that the DSR has brought to Vietnam and Southeast Asian countries, in the last section, the policy implications for cooperation are discussed.

• 한국지반환경공학회 논문집
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• 제24권12호
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• pp.19-29
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• 2023

도로의 주된 문제는 표층에서부터 작용하는 하중으로 인해 시간이 지남에 따라 균열 및 침하가 발생한다. 이러한 문제를 해결하기 위한 방법 중 하나로 지오셀(Geocell)을 사용하는 것이 있는데, 지오셀은 침식 방지, 평지 및 급경사지에서의 지반 안정화, 하중지지 및 지반 보전을 위한 구조적 보강을 위해 사용될 수 있다. 본 연구에서는 국내외 지오셀을 활용한 도로포장 적용 사례를 분석하고, 현장 시험과 LFWD(Light Falling Weight Deflectometer) 장비를 이용한 지오셀이 포함된 도로 포장 공법에 따른 지지력을 분석하고 기존도로포장 공법과 지지력을 비교·분석 하고자 한다.

• 한국물환경학회지
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• 제33권2호
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• pp.123-129
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• 2017

The purpose of this study is to identify potential methodologies to reasonably estimate the effectiveness of road vacuum cleaning in terms of pollution loads reduction. In this context, this study proposes two empirical equations to estimate the amount of diffuse pollution loads removed by road vacuum cleaning. The proposed equations estimate the removed amount of pollution loads respectively taking into consideration of: a) the distance of road vacuum cleaning; and b) the amount of road-deposited sediment(RDS). All of the parameters in these equations were evaluated based on results of field monitoring and laboratory analyses, except for the RDS generation rate. The results of this study suggest that pollutant removal efficiency is 46.3% for $BOD_5$ and 56.4% for TP; discharge ratios for particulate and dissolved $BOD_5$ are 35.0% and 21.2%, respectively; discharge ratios for particulate and dissolved TP are 35.0% and 19.4%, respectively. Average concentrations of pollutants in RDS are $BOD_5$ 977.3 mg/kg and TP 317.6 mg/kg. Some results of a case study imply that both equations can be potentially useful if the adopted parameters are reasonably evaluated. In particular, the RDS generation rate should be evaluated based on monitoring data collected from various road conditions.

• 한국도로학회논문집
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• 제7권4호
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• pp.185-202
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• 2005

본 연구에서는 현장 실험 조성의 제약을 극복하기 위해 3차원 가상현실(virtual reality)로 설계중인 도로를 모델링한 후, 피실험자가 Eye camera가 장착된 차량 시뮬레이터 (driving simulator)에 탑승하고 주행하면서 운전자가 행하는 선형변화에 대한 동적 반응 및 운전자의 시각행태에 대한 데이터를 획득하였다 본 실험에 적용된 차량시뮬레이터의 그래픽 모듈은 동역학 해석 모듈에 의해 얻어진 데이터를 기초로 하여 운동재현기와 가상환경의 일치감들 최대로 함으로써 피실험자로 하여금 차량시뮬레이터의 비현실성 및 부작용을 최소화하도록 하였다. 또한, Eye camera는 기존의 여타 장비와는 달리 운전자가 헬멧이나 렌즈 등 어떠한 부착장치도 착용하지 않고 실험할 수 있는 FaceLAB을 사용함으로써 운전자의 자연스러운 시각행태를 아무런 데이터 손실없이 획득하였다. 본 연구에서는 조사된 데이터를 바탕으로 도로 안전성을 평가하기 위해 차량 시뮬레이터, Eye camera방법을 통해 설계시 도로 기하구조 변화에 따라 운전자가 느끼는 안전성의 변화를 파악함으로써 도로 기하구조 조건과 안전성의 상관성을 명확하게 규명하고 이를 통해 운전자가 도로 주행시 편안하고 쾌적한 주행을 보장받을 수 있는 도로를 설계 단계에서부터 평가할 수 있는 방법을 제시하려고 한다.