• 한국대기환경학회지
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• 제25권3호
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• pp.188-195
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• 2009

Generally. mobile sources of air pollution were classified in on-road and non-road. Due to increased registration number of construction equipment in Korea. updated emission factors for non-road mobile sources, such as construction machinery. should be developed. NONROAD model of U.S. EPA already has introduced transient adjustment factors and sulfur adjustment factors for emission factors of diesel powered engine. In addition to this. European Environment Agency (EEA) has proposed emission factors for off-road machinery including several types of construction equipment. In this study. six types of construction equipment, such as excavator. forklift, loader, crane, roller and bulldozer, were studied to estimate emission factors based on total registration status in Korea. Total 445 construction equipments between 2004 and 2007 model year were tested with KC1-8 mode and air pollutants (CO, THC, $NO_x$, and PM) were measured. After statistical estimation and calculation, emission factors for CO, THC, $NO_x$, and PM for excavator, forklift, loader, crane, roller and bulldozer were provided and compared with previous emission factors. Moreover, updated emission factors for six types of construction equipment in this study were verified after comparison with emission factors of U.S. EPA. Finally, estimated emission amounts of four air pollutants were suggested according to six types of construction equipment.

• 대한교통학회지
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• 제32권4호
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• pp.410-420
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• 2014

본 연구에서는 트램의 능동식 우선신호를 위해 해석적 방법을 이용하여 신호시간 및 트램의 교차로 대기시간을 산정하기 위한 모형을 제시하였다. 본 모형을 통해 상류부 검지기에서 트램이 검지된 시간을 기준으로 능동형 우선 신호 기법 중 Early Green 및 Green Extension을 위한 신호시간을 결정할 수 있다. 또한 본 모형은 트램 통행의 관점에서 트램의 교차로 지체를 의미하는 트램의 교차로 대기시간을 산정할 수 있다. 우선신호의 구동환경에서 비우선 현시의 잔여녹색시간에서 우선현시의 추가녹색시간을 제공하게 되며, 트램은 비우선현시의 최소녹색시간 동안 교차로에서 대기하게된다. 본 모형에서는 우선신호의 신호시간 및 트램의 교차로 대기시간을 해석적 방법으로 모형화하였다. 독립교차로를 대상으로 하는 사례분석에서는 120초의 주기길이에 비우선현시의 여유녹색시간을 44초에서 10초까지 적용하여 트램의 평균 교차로 대기시간이 12.7초에서 29.4초까지 산정됨을 확인하였다.

• 한국도로학회논문집
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• 제8권4호
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• pp.37-47
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• 2006

도로상에서 운전자에게 길안내 역할을 하는 도로표지는 운전자가 자신이 원하는 목적지를 쉽고 정확하게 찾을 수 있도록 설계되고 설치되어야 하며, 이는 도로이용자의 도로이용 효율성 및 교통 안전성 향상을 위해 충분히 고려되어야 한다. 현재 우리나라에서 사용하고 있는 도로표지 경로안내방식은 점개념 안내방식이며, 도시부에서는 부분적으로 선개념 안내방식을 도입하고 있으나 안내지명 선정방법에 대한 기준이 미흡하고, 도로의 기능별 안내지명선정 및 지역적 특성을 감안한 안내지명 선정에 대한 구체적인 기준이 없어 안내지명간의 전체적인 연계성이 결여되는 문제점이 나타나고 있다. 따라서 본 연구에서는 현 도로표지규정집에서 규정하고 있는 도로표지 안내지명 선정기준을 재검토하여 특정 구간(지역)에서의 안내지명 선정방법 및 연계성을 확보하는 과정에서 발생할 수 있는 문제점을 다각적으로 분석해 보고, 도로의 기능별 및 지역적 특성을 감안한 안내지면 선정방법을 도출하는 것을 목적으로 한다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제11권1호
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• pp.51-58
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• 2022

첨단 운전자 보조 시스템(advanced driver assistance system)의 주요 기능 중 하나인 주행 가능 영역 검출은 차량이 안전하게 주행할 수 있는 영역을 검출하는 것을 의미한다. 주행 가능 영역 검출은 운전자의 안전과 밀접한 연관이 있으며 실시간 동작과 높은 정확도 성능을 요구한다. 이러한 조건들을 충족하기 위해, 영상의 각 행에서 도로 시차 값을 계산하여 주행 가능 영역을 검출하는 V-시차 기반 방법이 폭넓게 사용된다. 그러나 V-시차 기반 방법은 시차 값이 정확하지 않거나 객체의 시차 값이 도로의 시차 값과 동일한 경우, 도로가 아닌 영역을 도로로 오검출할 수 있다. 또한, 고속도로 및 시골길과 같이, 초목을 포함한 도로 환경에서 초목의 시차는 도로의 시차 특성과 매우 유사하기 때문에 초목 영역이 주행 가능 영역으로 오검출될 수 있다. 이에 본 논문에서는 V-시차의 특성으로 인한 오검출 횟수를 감소시킴으로써 초목 영역을 포함한 도로 환경에서 높은 정확도를 갖는 주행 가능 영역 검출 방법 및 하드웨어 구조를 제안한다. 제안하는 방법의 성능을 평가하기 위해 KITTI road dataset의 289장 영상을 사용하였을 때, 제안하는 방법은 90.12%의 정확도와 97.96%의 재현율을 보인다. 또한, 제안하는 하드웨어 구조를 FPGA 플랫폼에 구현하였을 때, 제안하는 하드웨어 구조는 8925개의 slice registers와 7066개의 slice LUTs를 사용한다.

• 한국입자에어로졸학회지
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• 제8권3호
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• pp.111-120
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• 2012

In Daegu, a road cleaning system was constructed in the central part of the city and has been operated from April, 2011. We evaluated the effect of the system on the concentration of $PM_{10}$ at a roadside monitoring site. The ambient $PM_{10}$ concentration data were logged every 1 min for a period of 20 weeks from May to October, 2011, by means of light scattering method, and then every 5 min data were used in the statistical analysis. The measured data were verified by comparing them with beta-ray data obtained at the same site. Correlation coefficient between the two groups was highly significant (r=0.79), though the absolute levels of light scattering data appeared to be approximately 2.8 times higher than the beta-ray data. Diurnal, daily, weekly, and monthly variations of $PM_{10}$ data did not show any evidence of decreasing effect owing to the clean road system. A comparison of roadside $PM_{10}$ data with non-roadside data also revealed very similar pattern, implying the variation of the $PM_{10}$ concentrations is mainly affected by the traffic conditions near the monitoring site. However, if the operating conditions of the clean road system can be improved, i.e. increasing the frequency and duration of water cleaning, the road cleaning effect may improve the air quality indirectly by means of removing the resuspended particles from the road.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.544-549
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• 2003

In this study, non-linear dynamic FE analysis of a tracked vehicle under the traveling load is performed by FE code ABAQUS. The stability of vehicle is examined using the structure analysis for the road wheel. The dynamic analysis is performed by traveling load. The traveling load include the 6 step loading spectrum about road wheel. The stress level around road wheel are 30 MPa ${\sim}$ 40 MPa. These value are indicated under modified fatigue strength 50.3 MPa. It takes about 3 second to be stable the structure after traveling load.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.252-254
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• 2003

In this study, it was purposed to develop the new method for the prediction of pollutant concentration in road tunnels. The new method was the use of artificial neural network with the back-propagation algorithm which can model the non-linear system of tunnel environment. This network system was separated into two parts as the visibility and the CO concentration. For this study, data was collected from two highway road tunnels on Yeongdong Expressway. The tunnels have two lanes with one-way direction and adopt the longitudinal ventilation system. The actually measured data from the tunnels was used to develop the neural network system for the prediction of pollutant concentration. The output results from the newly developed neural network system were analysed and compared with the calculated values by PIARC method. Results showed that the prediction accuracy by the neural network system was approximately five times better than the one by PIARC method. ill addition, the system predicted much more accurately at the situation where the drivers have to be stayed for a while in tunnels caused by the low velocity of vehicles.

• Macromolecular Research
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• 제15권2호
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• pp.129-133
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• 2007

Significant progress has been realized in the design and synthesis of light emitting polymers that emit over the entire visible spectrum. However, up to seventy-five percent of charge recombination events can lead to triplet states that decay non-radiatively. Following the pioneering work in the field of small molecule organic light emitting devices, it has been found that solution processible iridium polymer complexes can be used to harness the wasted triplet energy. In this paper, new results with respect to the electrophosphorescence of solution processible tethered iridium polymer derivatives are presented. Furthermore, our approaches to the design of new high triplet energy conjugated polymer hosts are also reported.

• 한국도로학회논문집
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• 제15권1호
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• pp.47-56
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• 2013

PURPOSES: This study is to evaluate a ground water level effect on frost heaving in road pavements. METHODS: The effects of water table on frost heaving in pavement systems were evaluated from the mechanical analysis using FROST program. The input parameters and boundary conditions were determined by considering climates, pavement sections, and material properties specially subgrade soil types in Korea. RESULTS: When the water table located above the freezing depth, amount of frost heaving caused by freezing the water in pavement itself was big enough to damage in pavement system, although pavement system consists of fully non-frost-susceptible materials with sufficient thickness of anti-freezing layer. The amount of frost heaving was decreased rapidly with increasing the distance between the water table and freezing depth. CONCLUSIONS: It was concluded that there is no engineering problems related with frost heaving in practical sense when the distance between freezing depth and water table is over 1.5m for having subgrade soils less than 50% of #200 sieve passing to meet specification on quality control in Korea.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.47.5-47
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• 2001

In this paper. a road-adaptive LQG control for the semiactive Macpherson strut suspension system of hydraulic type is investigated. A new control oriented model, which incorporates the rotational motion of the unsprung mass, is introduced. A semi-active suspension controller adapting to road variations is proposed. First, based on the extended least squares estimation algorithm, a LQG controller adapting to the estimated road characteristics is designed. Through the computer simulations, the performance of the proposed semi-active suspension is compared with that of a non-adaptive one. The results show better control performance of the proposed system over the compared one.