• 한국강구조학회 논문집
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• 제21권3호
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• pp.221-232
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• 2009

본 논문에서는 압엽형강(H형강)을 이용한 초간편 강합성 교량에 대한 3차원 유한요소해석을 실시하여, 다양한 하중조건에 따른 하중분배값을 검토하였다. 유한요소해석에는 범용구조해석 프로그램 ABAQUS(2007)가 사용되었다. 하중분배계수 검토에 고려된 변수로는 콘크리트 슬래브 두께, 강판 두께, 주형길이, 바닥판 폭, 그리고 교량 연속성이 적용되었다. 해석을 통해 얻어진 하중 분배율은 AASHTO Standard 와 LRFD 설계기준의 제안식 및 기존 연구자들이 제안한 식들과 비교 검토되었다. AASHTO Standard는 매우 안전측의 하중분배율을 제안하고 있으며, AASHTO LRFD의 경우 내측주형의 경우 유사한 결과를 나타내기도 했으나 외측주형의 경우 대부분의 경우 큰 값을 나타내었다. 본 연구를 통해 제안된 하중분배값은 유한요소해석 결과를 토대로 안전측으로 제안되었으며, 설계변수별 상세설계에 적용가능하다. 또한 본 논문에서는 초간편 강합성 H형강 교량의 설계 간편성을 극대화하고 안전성을 고려하여 내측주형의 경우 0.42, 외측주형의 경우 0.32를 제안하였다. 본 연구내용에 검토된 매개변수 범위 내에서 간편 하중분배값의 적용이 가능하며, 본 연구의 결과는 초간편 강합성 H형강 교량의 설계 및 시공 활성화에 크게 기여할 것이다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.277-282
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• 2006

Road traffic noise is not produced by any one factor rather occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examined the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/hr, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.

• 한국소음진동공학회논문집
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• 제17권3호
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• pp.274-281
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• 2007

Road traffic noise is not produced by any one factor rather it occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of any noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examines the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/h, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.

• 대한토목학회논문집
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• 제36권3호
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• pp.375-384
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• 2016

현행, 도로교설계기준에서는 교량바닥판에 대해 지간이 짧은 다거더 플레이트 거더교 위주의 규정을 두고 있으며, 강합성 소수 거더교에 적용되는 장지간 바닥판에 대한 설계규정은 명확하게 없는 실정이다. 이는 소수 거더교의 장지간 바닥판에 적용하기에는 한계가 있으므로 합리적인 설계를 위해서는 관련 규정을 보완할 필요가 있다. 따라서, 본 연구에서는 내측부 교량바닥판의 지간 6.0~12.0m 범위를 대상으로 도로교설계기준의 KL-510 하중을 적용하여 교축방향(종방향)과 교축직각방향(횡방향)에 대한 설계휨모멘트를 제안하였다. 설계휨모멘트는 바닥판의 직교 이방성, 거더의 강성, 그리고 다차로재하계수의 영향이 반영되었으며, 이를 기존의 DB-24 하중에 대한 설계휨모멘트와 비교하였다.

• 대한기계학회논문집A
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• 제23권6호
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• pp.931-942
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• 1999

This paper develops a 3 DOF vehicle model which includes lateral, roll and yaw motion to study a 4WS vehicle. The model is used for the simulation of a 4WS vehicle behavior, and to derive a control algorithm for rear wheel steering. This paper uses a feedforward plus feedback control scheme to compute a rear wheel steering angle. The feedforward control scheme for computing the first rear wheel steering angle uses a gain which is acquired by multiplying a proper value on a gain to maintain a zero sideslip angle. The feedback control scheme for computing the second rear wheel steering angle uses fuzzy logic and model following control scheme. A linear 2 DOF model is used as a reference model for model following control, and is derived from the developed 3 DOF model by neglecting sprung mass roll motion. A reference state variable is yaw rate, and is computed using the linear 2 DOF model. J-turn and lane change maneuver simulation are performed to show the effectiveness of the developed control scheme. The simulation results show that the 4WS vehicle with the developed control scheme has much better performance in yaw rate, lateral acceleration, roll angle, and sideslip angle than the 2WS vehicle. Also, the results show that the performance of the developed control is close to the one of an optimal control which assumes all states are perfect.

• 대한교통학회지
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• 제34권3호
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• pp.263-277
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• 2016

고속도로 공사구간은 차로의 차단 및 공사구간 내 다양한 시설물에 운전자가 노출되기 때문에 사고가 빈번하게 발생하는 구간이다. 공사구간 중 완화구간은 차로차단으로 인하여 차량의 합류가 발생하므로 사고의 위험도가 높다. 따라서 본 연구에서는 주행 시뮬레이션(Driving Simulation)과 교통 시뮬레이션 (Traffic Simulation)의 연계 분석을 적용하여 세 가지 유형의 차로합류 기법에 대한 안전성을 비교 평가하였다. 분석 결과, 기존 차로차단 기법보다 사전 유도기법 또는 Joint Merge기법이 안전성 측면에서 효과적인 것으로 나타났다. 서비스 수준(LOS) A, B인 경우 사전 유도기법이 적정 합류기법으로 판단되었으며, 서비스 수준 C의 경우 Joint Merge기법이 적정 합류기법으로 판단되었다. 본 연구는 현재 운영되고 있는 차로차단 기법 외에 공사구간 교통상황에 따른 다양한 합류기법의 적용 타당성을 주행 및 교통 시뮬레이션의 연계분석을 통하여 안전성 관점에서 평가하였다는 데 의의가 있다.

• 자동차안전학회지
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• 제4권1호
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• pp.12-17
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• 2012

ADAS(Advanced Driver Assistance System) which is developed for alleviating driver's load has become improved with extending it's role. Previously, ADAS offered simple function just to make driver's convenience. However, nowadays ADAS also acts as Active Safety system which is made to release and/or prevent accidents. Longitudinal control system, as one of major parts of Active Safety System, is assessed as doing direct effect on avoiding accidents. Therefore, many countries such as Europe and America has pushed longitudinal control system as a government-wide project. In this paper, it covers the result of evaluation system and vehicle evaluation for development study in FCW, ACC and AEB.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.197-203
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• 2003

Korea Highway Corporation(KHC) began the ambitious KHC Test Road construction project from 1997. It is 7.7km long two-lane highway next to the mainline of Jungbu Inland Expressway. The KHC Test Road construction was completed at the December 2002. It is composed of twenty-five PCC test pavement sections. Section design parameters are (1) concrete slab thickness, (2) base type, (3) base thickness (12, 15, and 18cm), and (4) pavement type. Twenty-five PCC test pavement sections contain 1241 sensors to evaluate the behavior of pavement system under traffic load and environmental change. The behavior of pavement systems will be identified by the observation of sensor measurement and pavement distress survey from test pavement sections. The Test Road research outcome will validate the Korean Pavement Design Guide which is develop by on-going funded research from the Ministry of Construction and Transportation.

• 한국자동차공학회논문집
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• 제7권5호
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• pp.162-171
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• 1999

The most important part in automated transport systems is steering control for lane keeping Most of systems developed so far have used the visual information for steering control. In this study, the steering control algorithm based on visual servoing has been developed and tested by applying it on Radio Controlled(R/C) model car equipped with one CCD camera. We also demonstrated the feasibility of using it as a pre-test car before the real car experiment in developing automated vehicles. In order to solve the problem of the limited spave and load of a model car, remote-brained approach has been taken. For steering control of a model car, the PD controller which uses the look ahead offset to generate control input has been implemented and the characteristics of the controller has been explained in view of kinematics. Some experimental results have been also illustrated so as to show the control performance and stability.

• International Journal of Automotive Technology
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• 제7권3호
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• pp.303-307
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• 2006

This paper presents the enhancement of vehicle stability by active geometry control suspension(AGCS) system as the world-first, unique and patented chassis technology, which has more advantages than the conventional active chassis control systems in terms of the basic concept. The control approach of the conventional systems such as active suspensions(slow active, full active) and four wheel steering(4WS) system is directly to control the same direction with acting load to stabilize vehicle behavior resulting from external inputs, but AGCS controls the cause of vehicle behaviors occurring from vehicle and thus makes the system stable because it works as mechanical system after control action. The effect of AGCS is the remarkable enhancement of avoidance performance in abrupt lane change driving by controlling the rear bump toe geometry.