• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.302-307
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• 2010

Development of light-weight high speed train (HST) based on distributed motor control with the top speed of 350 km/hr has engendered a need for abatement of the interior noise of the train cabin. The development of noise abatement measures is crucial at the design stage of the train car since the noise transmission characteristics of the car structure directly influences the cabin interior noise. Since the transmission loss measurement using the entire car structure is often not feasible, especially at the initial stages of the train development, investigation of transmission characteristics using small-scale reverberation chamber can furnish useful alternative source of predicting the noise level. In the present study, white noise is generated at source and transmission loss estimated by performing measurement of a specimen in a scaled reverberation chamber. Comparison of measured values with the previously derived numerical values show good agreement in the overall trend but appreciable quantitative differences still remain.

• 한국산업융합학회 논문집
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• 제22권3호
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• pp.273-280
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• 2019

Carbon fiber composite laminate has been widely used in the area of sports applications such as race car, golf club, fishing rods, yacht. In this study, carbon fiber composite laminate was used in the rear upright of leisure purposed small size single-seat electric race car to reduce its unsprung mass of suspension system. The focus of this research is to investigate in finding optimal stacking lay-up of rear upright laminated with carbon fiber composite in the early design phase. Forces transferred from circuit road to rear upright were estimated through MBD(Multi-Body Dynamics)model of the rear suspension geometry. To evaluate the strength of the rear upright laminated with carbon fiber composite which generally behaves in an anisotropic or orthotropic manner, FEA(Finite Element Analysis) model suitable for composite materials was built followed by its strength was evaluated depending on different stacking lay-up. The result showed that Symmetric stacking lay-up [$45^{\circ}/-45^{\circ}/90^{\circ}/0^{\circ}$]s for frontal area and symmetric stacking lay-up with 1mm aluminum core [$45^{\circ}/-45^{\circ}/90^{\circ}/Core$]s for rear area were most suitable of 16 lay-up cases from the side of both strength based on Tasi-wu failure index and weight.

• 한국빅데이터학회지
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• 제6권1호
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• pp.179-196
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• 2021

코로나19로 인한 언택트 문화의 확산으로 타인과 접촉을 최소화할 수 있는 차박 시장의 규모가 확대되고 있다. 이에 차박캠핑에 용이한 SUV의 경우 승용 세단 판매량을 넘어섰고, 레저용 차량(RV)의 판매량은 작년 동기 대비 101% 증가하였다. 이러한 폭발적인 차박 수요의 증가에도 불구하고 차박 관련 연구는 저조하다. 이에 본 연구에서는 차박 이용자 중심의 연구를 진행하고자 하였다. 네이버 대표 차박 카페를 조사한 결과, 여러 장소의 차박지가 하나로 정리되어있는 글이나 지도, 웹사이트는 찾기 어려웠다. 또한, 기존의 캠핑 웹사이트들을 분석한 결과, 대부분 캠핑장소에 대한 정보만을 게시하고 있어 차박지의 자세한 정보를 알 수 없었다. 이에 더하여 관련 선행연구와 문헌조사를 통해 도출한 설문조사에 따르면 차박지내 쓰레기 무단 투기 문제에 대한 해결방안을 촉구하는 의견이 다수였다. 또한, 이용자들은 차박지 근처 편의시설 정보를 제공받고자 하였다. 따라서 차박지의 기본정보와 차박지 근처 편의시설 정보를 제공하는 차박 캠핑 웹사이트를 구축하고자 하였으며, 클린캠핑 인증 기능을 제공하여 차박지 쓰레기 무단투기 문제를 해결하고자 하였다. 더 나아가, 주요 웹사이트 기능인 클린캠핑 인증을 발전시켜 비즈니스 모델을 고안하였다. 비즈니스 모델은 차박 이용자들이 클린캠핑 인증 절차를 거쳐 보상을 받는 구조로 설계하였다. 클린캠핑 인증에 대한 보상은 국내 자동차 회사, 한국관광공사, 소상공인시장진흥공단과의 제휴를 통해 제공될 수 있도록 제안하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.53-56
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• 2001

This paper has been developed a millimeter-wave radar to prevent car collision. This system needs to progress the problem as follows; (1) Increase of traffic accidents causing damage and injuries due to the increased number of motor vehicles and long distance driving, (2) Need for a device to help drivers who are in trouble due to bad weather conditions. (3) Need for a millimeter-wave radar as obstacles which need to be detected are small. This system is composited with some major technologies, Narrow beams to recognize obstacles or other objects, One-side circuit technology to prevent interference between electric waves, and Parts designed for radar products which are able to transmit millimeter - waves. The system has a various a application Field, Car distance auto-control system, prevent bump collision due to unexpected stoppage of the front car or careless driving, obstacle warning system, Car following system, and industrial and military purposes system. We have a looking forward to propose to develop field tests under various road conditions and hybrid car sensor by combining with other sensors

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.916-919
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• 2004

The monopole theory has long been used to model air-pumped effect from the elastic cavities in car tire. This approach models the change of an air as a piston moving backward and forward on a spring and equates local air movements exactly with the volume changes of the system. Thus, the monopole theory has a restricted domain of applicability due to the usual assumption of a small amplitude acoustic wave equation and acoustic monopole theory. This paper describes an approach to predict the air-pumping noise of a car ave with CFD/Kirchhoff integral method. The type groove is simply modeled as piston-cavity-sliding door geometry and with the aid of CFD technique flow properties in the groove of rolling car tyre are acquired. And these unsteady flow data are used as a air-pumping source in the next Cm calculation of full tyre-road geometry. Acoustic far field is predicted from Kirchhoff integral method by using unsteady flow data in space and time, which is provided by the CFD calculation of full tyre-road domain. This approach can cover the non-linearity of acoustic monopole theory with the aid of using Non-linear governing equation in CFD calculation. The method proposed in this paper is applied to the prediction of air-pumping noise of modeled car tyre and the predicted results are qualitatively compared with the experimental data.

• 한국산업융합학회 논문집
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• 제25권3호
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• pp.407-415
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• 2022

In this study, a square rounding sidewalk block frame was developed considering the simplicity of construction and the superiority of aesthetics. In addition, it is possible to prevent damage, deformation, and settlement of adjacent sidewalk blocks due to plastic deformation during car impact load of installed bollad. A non-linear structural analysis was performed through finite element analysis to examine the performance of a car crash to which this was applied. Structural safety was confirmed through car crash simulation according to the direction of impact, and it is estimated that the function can be restored by replacing some parts in case of damage due to impact.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.959-964
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• 2007

In this study, it is offering a numerical method which assesses running safety of the freight car loaded CWR when passing through on the conventional railway by additional lateral load. It is suggested based on the numerical reviews of the safety against derailment after seeking the derailment coefficient estimated by wheel load-lateral force equation in the section that curve radius is small

• 한국공간구조학회논문집
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• 제11권1호
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• pp.105-112
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• 2011

전기자동차의 상용화시대에 대비한 전기자동차 충전네트워크가 시급해지고 있다. 해외에서는 주차장에 PV시스템을 설치하여 얻어진 전력으로 전기자동차 충전을 할 수 있는 전기자동차 충전소가 설치되어지고 있다. 또한 우리나라에서도 충전인프라 구축방안 및 전기자동차 충전시설 지원기준 등을 설정하여 제시하고 있지만 해외처럼 PV시스템을 이용한 전기자동차 충전소의 사례가 국내에는 없으며, 일반전력을 이용한 전기자동차 충전소만 제시하고 있다. 따라서 본 논문에서는 국내의 전기자동차 충전네트워크 구축에 대비하여 국내 외 태양광 주차장과 해외 PV시스템 전기자동차 충전소의 사례를 조사하여 구조시스템, 구조 재료 등을 분석하여 비교 분석한 결과, 해외 PV시스템 전기자동차 충전소의 경우 캔틸레버 구조와 소규모 타입이 많이 설치되었다.

• International Journal of Automotive Technology
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• 제7권7호
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• pp.833-839
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• 2006

In this paper, roll behavior of three planar half car models are compared. The first model is a simple model whose contact point between a wheel and the ground is assumed to be fixed with a revolute joint. The second model is a modified model of the fIrst model, whose wheel tread width can vary. In this model, the instant center of a wheel with respect to the ground, which is crucial to find the roll center, is assumed to be at the contact point of a wheel and the ground. The last model uses the pole of a wheel with respect to the ground for small displacement as the instant center of a wheel with respect to the ground. Loci of the center of gravity point, the fixed and the moving centrodes which are traces of roll center position in the ground and the body frame respectively, wheel contact points, and instant centers of a wheel with respect to the ground are calculated.

• Communications for Statistical Applications and Methods
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• 제18권4호
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• pp.549-557
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• 2011

In this paper, we apply cluster analysis to "Okayama parking data" that is one of the spatial point patterns data that includes locations and the fare structure of car parking space in Okayama central area. This study classifies the characteristics of small areas through Okayama parking data as well as visualizes the results of the cluster analysis. We develop web applications that connect the results of a cluster analysis and overlay objects including points of balloons and rectangles of small areas over a map of Okayama central area.