• 제어로봇시스템학회논문지
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• 제21권2호
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• pp.121-129
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• 2015

This paper presents a multiple vehicle recognition algorithm based on radar and vision sensor fusion for lane change assistance. To determine whether the lane change is possible, it is necessary to recognize not only a primary vehicle which is located in-lane, but also other adjacent vehicles in the left and/or right lanes. With the given sensor configuration, two challenging problems are considered. One is that the guardrail detected by the front radar might be recognized as a left or right vehicle due to its genetic characteristics. This problem can be solved by a guardrail recognition algorithm based on motion and shape attributes. The other problem is that the recognition of rear vehicles in the left or right lanes might be wrong, especially on curved roads due to the low accuracy of the lateral position measured by rear radars, as well as due to a lack of knowledge of road curvature in the backward direction. In order to solve this problem, it is proposed that the road curvature measured by the front vision sensor is used to derive the road curvature toward the rear direction. Finally, the proposed algorithm for multiple vehicle recognition is validated via field test data on real roads.

• International Journal of Automotive Technology
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• 제6권2호
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• pp.183-190
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• 2005

During normal operating conditions, a motor vehicle is constantly subjected to a variety of forces, which can adversely affect its straight-ahead motion performance. These forces can originate both from external sources such as wind and road and from on-board sources such as tires, suspension, and chassis configuration. One of the effects of these disturbances is the phenomenon of vehicle lateral-drift during straight-ahead motion. This paper examines the effects of road crown, tires, and suspension on vehicle straight-ahead motion. The results of experimental studies into the effects of these on-board and external disturbances are extremely sensitive to small changes in test conditions and are therefore difficult to guarantee repeatability. This study was therefore conducted by means of computer simulation using a full vehicle model. The purpose of this paper is to gain further understanding of the straight-ahead maneuver from simulation results, some aspects of which may not be obtainable from experimental study. This paper also aims to clarify some of the disputable arguments on the theories of vehicle straight-ahead motion found in the literature. Tire residual aligning torque, road crown angle, scrub radius and caster angle in suspension geometry, were selected as the study variables. The effects of these variables on straight-ahead motion were evaluated from the straight-ahead motion simulation results during a 100m run in free control mode. Examination of vehicle behavior during straight-ahead motion under a fixed control mode was also carried out in order to evaluate the validity of several disputable arguments on vehicle pull theory, found in the literature. Finally, qualitative comparisons between the simulation results and the test results were made to support the validity of the simulation results.

• 한국환경생태학회지
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• 제28권5호
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• pp.597-606
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• 2014

본 연구는 산림치유 프로그램 개발을 위한 일반 성인의 숲과 숲길의 선호도에 관한 연구이다. 숲과 숲길의 선호도에 대한 수요자 선호를 파악하여 보다 표적화되고 차별화된 산림치유 프로그램의 개발을 위한 기초자료 제공을 목적으로 실시하였다. 이를 위해, 잠재 수요자인 일반 성인 남 여를 대상으로 2014년 4월 19일부터 6월 30일까지 온라인 설문으로 숲과 숲길의 선호에 관한 설문조사를 실시하였다. 본 연구에서는 총 613부의 유효표본이 실제 분석에 사용되었다. 자료분석은 SPSS 21.0 프로그램을 사용하여 기술통계분석, 빈도분석, 교차분석, 다중응답분석을 통해 인구통계학적 특성(성별, 연령, 교육수준, 직업, 월평균 가계 소득)에 따른 숲과 숲길의 선호도의 차이를 살펴보았다. 분석 결과, 선호하는 계절의 숲은 봄, 가을, 계절 상관없음, 여름, 겨울 순으로 나타났고, 성별, 연령, 월평균 가계 소득에 따라 선호도에 유의한 차이가 있는 것으로 조사되었다. 선호하는 상태의 숲은 월평균 가계 소득에 따라 선호도에 유의한 차이가 있는 것으로 조사되었다. 산림치유 프로그램 장소로서 선호하는 숲은 자연휴양림, 치유의 숲, 도시숲, 공원, 학교숲 순으로 응답하였다. 거주지로부터 프로그램 장소까지의 거리에 따른 선호하는 숲을 조사한 결과 모든 경우에 대해 통계적으로 유의한 차이가 없게 나타났다. 숲길의 형태에 관해서는 약간의 경사가 있는 길을 가장 선호하는 것으로 조사되었다. 산림치유 목적으로 1회 걸을 때 선호하는 숲길의 길이는 1.5~3km, 1.5km이하, 3km 이상 순으로 나타났고, 성별과 연령, 교육, 월평균 가계 소득, 교육에 따라 선호도에 유의한 차이가 있는 것으로 조사되었다. 이러한 산림치유 프로그램 개발을 위한 일반성인의 숲과 숲길조사를 통하여, 성별, 연령, 교육수준, 직업, 월평균 가계 소득에 따라 숲과 숲길에서의 프로그램에 차별성을 두어야 할 것으로 판단된다. 특히, 연령에 따라 차별화된 프로그램이 제공되어야 할 것으로 판단된다. 본 연구 분석 결과가 성인을 대상으로 하는 산림치유 프로그램 개발을 위한 기초자료로 활용되기를 기대한다.

• 한국공작기계학회논문집
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• 제17권5호
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• pp.10-22
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• 2008

In an automotive body structure, a design configuration that fulfills structural requirements such as deflection, stiffness and strength is necessary for structural design and is composed of various components. The integrated design is used to obtain a minimum weight structure with optimal or feasible performance based on conflicting constraints and boundaries. The mechanical design must begin with the definition of one or more concepts for structure and specification requirements in a given application environment. Structural optimization is then introduced as an integral part of the product design and used to yield a superior design to the conventional linear one. Although finite element analysis has been firmly established and extensively used in the past, geometric and material nonlinear analyses have also received considerable attention over the past decades. Also, nonlinear analysis may be useful in the area of structural designs where instability phenomena can include critical design criteria such as plastic strain and residual deformation. This proposed approach can be used for complicated structural analysis for an integrated design process with the nonlinear feasible local flexibilities between system and subsystems.

• Wind and Structures
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• 제26권1호
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• pp.35-43
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• 2018

This paper describes the effect of different testing parameters (configuration of infrastructure and truck position on road) on truck aerodynamic coefficients under cross wind conditions, by means of a numerical approach known as Large Eddy Simulation (LES). In order to estimate the air flow behaviour around both the infrastructure and the truck, the filtered continuity and momentum equations along with the Smagorinsky-Lilly model were solved. A solution for these non-linear equations was approached through the finite volume method (FVM) and using temporal and spatial discretization schemes. As for the results, the aerodynamic coefficients acting on the truck model exhibited nearly constant values regardless of the Reynolds number. The flat ground is the infrastructure where the rollover coefficient acting on the truck model showed lowest values under cross wind conditions (yaw angle of $90^{\circ}$), while the worst infrastructure studied for vehicle stability was an embankment with downward-slope on the leeward side. The position of the truck on the road and the value of embankment slope angle that minimizes the rollover coefficient were determined by successfully applying the Response Surface Methodology.

• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.152-161
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• 2022

Recently, it is recognized as a high-cost and inefficient logistics system that increases traffic congestion and environmental problems due to an increase in traffic volume due to the activation of the online market. In order to solve inefficient problems such as unavoidable traffic congestion and environmental problems caused by the increase in traffic volume, it is necessary to develop a freight transport system technology using the existing urban railway infrastructure and freight-only urban railway. The urban subway logistics system is a logistics system that requires a combination of various technologies to solve the nationwide demand for urban logistics and road traffic problems. This paper recognized the existing traffic congestion and environmental pollution of road traffic as problems, and supplemented the contact point requirements presented above by identifying the sub-systems constituting the target system and supplementary points for each part-level contact point. In this study, as a complex system operated for one purpose by grafting various technologies, a plan is required to secure the reliability and safety of operation from various viewpoints. The results of this study can contribute to the initial configuration and basic data to solve the interface bottleneck of the urban subway logistics system to be promoted in the future.

• 한국ITS학회 논문지
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• 제3권1호
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• pp.75-83
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• 2004

본 논문에서는 ITS 서비스 구성 요소 중의 하나인 ETCS(Electronic Toll Collection tsystem)에서 RSE(Road Side Equipment) 기지국 gantry에 장착되어 이동체와 무선 통신 링크를 연결해 주는 ETCS 기지국유 안테나를 설계 및 제작하고 그 특성을 측정하였다. ETCS 기지국용 안테나 특성은 적은 부엽 특성과 도로 상황과 이동체 탑재되는 OBU 위치에 따라 특정 형태의 빔 패턴이 요구된다. 또한 반사에 의한 multipath 신호 영향을 최소화하기 위해 원형편파 특성이 요구된다. 저 부엽의 빔 패턴을 얻기 위해 배열 패치 구조와 Taylor distribution에 의한 방사요소의 전류 weighting factor를 적용하였다. 제작된 안테나의 동작 중심 주파수는 5.8GHz이고, 반사손실은 -10 dB를 기준으로 130 MHz, 10MHa사용 대역내에서 축비 2.6 dB이하의 RHCP 편파 특성과 17 dBi 이득을 얻었으며, 빔 패턴은 시뮬레이션 결과와 측정 결과가 잘 일치하고 있음을 보여주었다.

• 대한안전경영과학회지
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• 제14권3호
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• pp.175-181
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• 2012

This example was able to focus on the long usage of the pavement that it was merely through the oxidation of the asphalt pavement which it could contact with on the road in the industrial housing complex and correlation regulation of the asphalt subsidence with the load in basic Infra of the configuration. The problem in conjunction with the subsidence (transformation) was interpreted as a problem of the subsidence of each pavement layer to lead the subsidence of the road or the transformation to packaging side asphalt pavement, but the traffic number of times of the heavy vehicle highlights for main problems with the road where is concentrated. In the case of general asphalt paving, it thinks it exposes light, and to study a general phenomenon for the asphalt transformation and a cause for a pavement construction method and the property of material used for pavement and a complement method by the case study at this time of the compound with the heavy vehicle traffic that it can become clear that small success transformation occurs at a point in time when 1-2 years more pass, and a fatigue rift occurs by ultraviolet rays, the oxidation with the contact with the air afterwards, and described beginning to use by the above.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1735-1740
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• 2005

In this paper, ways of improving the performances of roundabouts under the assumption that the Advanced Vehicle System is proposed. The situation on a road contains uncertainty and complexity caused by different vehicles having different directions and time-varying traffic flow. This sort of system with high uncertainty is called Multi Agent System (MAS). The MAS is a collective system, including numbers of agents and performs high diversity of the configuration as well as it has nonlinear property and complexity. Hence it is difficult to analyze and control the multi-agent system. A roundabout can be considered as an MAS with numbers of moving vehicles. So it must be difficult to use a centralized control technique to all vehicles in an intersection. Therefore, to improve the performances of roundabouts, multi-agents flow control algorithm for vehicles in Roundabouts using 'self-organization' technique is proposed.

• 건축역사연구
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• 제17권1호
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• pp.47-64
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• 2008

The object of this research is to examine the planning principles of Sangju which has an old history The results of the investigation are as follow 1. Sangju placed on the plains in the castle, it is established in Korea Dynasty 2. The formation of Sangju is infruenced Feng-shui. They plants Chestnuts against centipede mountain 3. Sangju is similar to the configuration of the another city in Feng-shui and elements of Component. But, many buildings(jin-Young(Military site), Choong-Ui-Dan, Choong-Yeol-Sa) are associated with the war in Sangju. 4. The City hall is located on the west side of the hotel(Kaek-Sa). It is located on Wang-San which is a place where citizens with symbolism. So, the City hall is higher than Kaek-Sa 5. The cruciform style road which connected with 4 gates was formed in the castle.