• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 추계 학술대회논문집
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• pp.132-138
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• 2003

The optimal design for a leading car considering the aerodynamic resistance is required on the high-speed train due to increasing of ratio of drag force with proportion for the square of velocity. The aerodynamic analysis using CFD in the stage of concept design offers more economical analysis method which is used to estimate the influence of flow and pressure around the leading car than the experimental method using the Mock-up. In this study, we want to assist the artistic design with aerodynamics analysis in order to get the optimal design for leading car with the operation speed of 180km/h. The results of aerodynamic analysis for two leading car models which one is expressed with lineal beauty and the other is with curvaceous beauty are compared with each other and they offer the proposal of modification for two models in order to decrease the drag force. The shape of curvaceous model is better for the pressure force but slightly worse for the viscous force than the other. The Fluent software is used for the calculation of flow profile in this study.

• 대한건축학회논문집:계획계
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• 제35권6호
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• pp.47-58
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• 2019

According to the Korea Ministry of Transportation report in 2015, domestic used car trade (3.66million) is twice the number of new car sales (1.84million). However, contrary to the quantitative growth of the used car trading volume, chaotic used-car market practice has not been improved and also, space that holds these markets (facilities) has remained at a very low level of quality. Lemon Market, asymmetry of information, false bait, tout, dual contracts, negative words that qualify the used car market information are still in place. The aim of this study was to understand the unique circumstances of the used car sales market distinguished from new cars, and to analyse the problems of recent domestic used car market facilities and afterwards to draw guidelines for new used car facility architecture. Through literature review, surveys, the characteristics of domestic used car market have been organised and field research and competitive analysis of the Korea used car market architecture is followed. As a result, empirical guideline for Korea used-car market facility is introduced.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.259-262
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• 2008

This paper introduces a simplified method to consider forming effects in a car crash analysis. Representative value was used to consider forming effects simply. Four representative values, which are the mean value of thicknesses and effective plastic strains at nodes, the median of thicknesses and effective plastic strains at nodes, were evaluated. A crash analysis of a front side member shows that analysis results from the suggested methods are similar to those from the conventional method to consider forming effects. Use of the mean effective plastic strain shows the best results. A car crash analysis for a ULSAB/AVC model under the condition of US SINCAP were carried out to demonstrate the validity of the suggested method. Analysis results show that the error of suggested method is less than 1.5%.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.9-19
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• 2010

Every car manufacturer desires to reduce the new car development time spent in improving the safety, NVH, lightweight, reliability and environment friendly features of the car. Other considerations such as planning, exterior and interior styling, packaging, color, and material selection increase the complexity of the car design process. This paper proposes a personal DDP (Digital Design Process) to utilize the engineering analysis and design/styling software for car design. DDP can be efficiently used by a team of car research center or a studio with small number of engineers, helping ordinary engineers becoming ambidextrous in design as well as engineering applications. The concept model starts from idea sketch, rendering, and 3D surface model with CAS (Computer Aided Styling) to the final safety estimation by using proposed DDP based on engineering technology (CAD, CAE). The concept model proposed a hydrogen fuel cell sports coupe which could be available within next 10 years. The proposed DDP can not only reduce the new car development time but also be adapted into designing of varied products such as aircraft, yacht, electrical equipment and sports gear.

• 한국ITS학회 논문지
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• 제12권6호
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• pp.22-28
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• 2013

본 연구에서는 대전광역시를 대상으로 향후 카쉐어링 서비스를 제공할 경우를 가정하고 위치 선정방안을 제시하는 것을 목적으로 한다. 이를 위해 GIS Arc/Info 10 소프트웨어를 활용하여 대전광역시 전역을 $500m{\times}500m$ 크기의 셀로 구분하고 카쉐어링 서비스에 영향을 미칠 것으로 예상되는 요인들을 선정하고 각 요인들의 값을 표준화하는 과정을 거쳤다. AHP 기법을 도입하여 각 요인별 가중치를 전문가 설문을 통해 결정하고 모든 셀($500m{\times}500m$ 크기)별로 적합도 지수를 산정하였으며, 네트워크 분석(Network Analysis)모듈에 내장되어있는 입지배분모델(Location-allocation Model)을 이용하여 서비스 시설의 위치를 30개의 권역으로 선정하는 방안을 제시하였다. 본 연구에서 제안한 카쉐어링 서비스 위치선정을 위한 방안은 향후 카쉐어링 서비스가 도입될 때 기초 자료로 활용할 수 있을 것으로 기대되며, 향후 적정한 수요의 추정과 경제성 검토 등에 대한 추가연구가 필요할 것으로 판단된다.

• 대한교통학회지
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• 제35권2호
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• pp.105-115
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• 2017

지난 10년간 대한민국에서 발생한 전체 교통사고 수는 감소했지만, 사업용 차량의 교통사고는 꾸준히 증가하는 추세를 보이고 있다. 특히, 연중 많은 관광객이 방문하고 렌터카를 주 교통 수단으로 이용하는 제주도의 경우 렌터카 사고 문제로 심각한 인명 피해와 사회적 비용이 야기되고 있다. 이에 본 연구는 제주지역에서 발생한 렌터카 사고의 특성을 비사업용 일반승용차 사고 특성과 비교 분석하였고, 사고 감소 방안을 제시하였다. 본 연구에서는 지난 2년간(2014-2015년) 제주지역에서 발생한 918건의 렌터카 사고와 4,201건의 일반승용차 사고 데이터를 카이제곱검정 및 z-검정 등의 통계적 방법론을 활용하여 분석하였다. 분석결과 렌터카 사고와 일반승용차 사고의 특성은 상이한 것으로 나타났다. 렌터카 사고는 20-30대 젊은 운전자와 면허를 취득한지 얼마 되지 않은 운전자 비율이 높은 것으로 나타났으며, 인적 및 환경적 요인에 관련된 사고특성이 일반승용차와 유의한 수준 하에서 통계적으로 다르게 나타났다. 특히 운전 미숙, 낯선 지리, 익숙하지 않은 차량 등은 렌터카 사고를 유발하는 주요 원인으로 판단된다. 반면, 렌터카 사고 분석결과 차량적 요인에 대한 명확한 특징은 나타나지 않았다. 본 연구의 결과는 제주지역 뿐만 아니라 렌터카 운행이 증가하는 지역, 관광지 특성이 강한 지역에서 교통사고 특성 분석 및 교통안전대책 수립과정에서 유용하게 활용될 수 있을 것으로 판단된다.

• 한국철도학회논문집
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• 제17권5호
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• pp.381-389
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• 2014

본 연구에서는 카셰어링 이용특성자료 및 GIS를 활용하여 입지특성과 관련된 도시 및 지역적 사회경제에 대한 DB를 구축하였으며, 주성분분석을 통해 잠재변수를 도출하였고 요인점수를 활용한 다중회귀분석을 통해 영향변수의 의미를 살펴보았다. 업무중심지역 및 역세권지역, 대학교인근지역에서의 활용도가 높았고, 특히, 전기차에 대한 관심도가 카셰어링 이용도에 영향을 미치는 것으로 파악되었다. 한편, 금융기관이 집중된 지역 및 영업용(택시)차량 배치가 많은 지역에서는 이용이 제한되는 것으로 나타났다. 본 연구의 분석결과는 향후의 카셰어링의 활성화와 공유가치에 대한 시민의 이해도 향상과 소유에서 공유로의 발상전환에 기여할 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.369-372
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• 2007

about commercial business of car black box, mirror vision for car black box deal with analysis of Existing Car Black boxes in market to provide the objective information associated with surrounding scene of car instead of witness, we experimented on suitable structure of all direction to cover surrounding of car considering dead zone where can't see at short distance and realized simple structure of gathering scene using mirror and lens and by saving the number of camera and MUX of pre-circut

• 한국자동차공학회논문집
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• 제8권2호
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• pp.129-137
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• 2000

In the prototype stage of a car developing program, the efficiency of trouble shooting is an important factor to be considered. Structural modifications by the design sensitivity analysis are applied to a steering wheel system for improving the idle vibration of the prototype passenger car. For the design sensitivity analysis, the experimental modal analysis for the steering system attached to a body-in-white is fulfilled and the modal parameters extracted from the experimental data are used to predict the effect of structural modification, The design sensitivity results rank the locations to be reinforced in terms of frequency variation. The modification of steering system according to the sensitivity analysis results shifted the resonant frequency of the system effectively. In addition, the idle test of the car after the structural modifications f steering system shows that the proposed method can reduce vibration of the steering wheel efficiently.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1074-1079
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• 2011

This paper describes the influence on the nonlinear critical speed results of a specific railway vehicle depending on various constraint conditions. In the roller-rig tests, proper constraints are inevitable to safely hold the test vehicles. Particularly, the test results using KRRI roller-rig are more sensitive to constraint conditions because it is a kind of semi-full car type. In this study, nonlinear critical speed of specific vehicle with regards to several constraint cases were predicted by computational analysis and these results were compared to find the suitable constraint conditions. And also the deviation of semi-full car model from actual full car model was investigated. According to the bifurcation analysis, the nonlinear critical speed are dependent with the constraint condition and car-body yaw motion should be free to achieve more accurate results. And the difference between semi-full and full car model was so small that KRRI's semi-full car model are valid as long as the stability is concerned.