• Title/Summary/Keyword: road vehicle

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An Observation of the Application of a Magnetic Force to the Bicycle Cushion System and its Nonlinearity (자석 척력의 자전거 쿠션장치 적용 및 비선형성 고찰)

  • Yun, Seong-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.17 no.1
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    • pp.42-47
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    • 2018
  • This paper describes the dynamical behavior of the bicycle and its nonlinear effect when magnetic repulsive forces are applied to the bicycle cushion system. A finite-element method was used to obtain its reliabilities by comparing the experimental and numerical values and select the proper magnet sizes. The Equivalent spring stiffness values were evaluated in terms of both linear and nonlinear approximations, where the nonlinear effect was specifically investigated for the ride comfort. The corresponding equations of linear and nonlinear motion were derived for the numerical model with three degrees of freedom. Dynamic behaviors were observed when the bicycle ran over a curvilinear road in the form of a sinusoidal curve. The analysis in this paper for the observed nonlinearity of magnetic repulsive forces will be a useful guide to more accurately predict the cushion design for any vehicle system.

Sink holes material damage and mental harm analysis and risk assessment studies -Focusing on the incidents surrounding the construction site- (씽크홀의 물적손상과 정신적 피해분석 및 위험성 평가연구 -건설현장 주변의 사고사례를 중심으로-)

  • Lim, Jin Sang;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.17 no.4
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    • pp.153-160
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    • 2015
  • Recent News patrons of incidents can be called sinkhole that occurred one after another (Sink Hole). Due to this anytime, anywhere I do not know how the land is turned off worry and anxiety is the reason why you can never be dismissed as exaggerated. As we have seen today through the video, the vehicle was traveling on a road or pedestrian who was walking down the street they look out of the basement of a sudden they still come to mind vividly. Here, examples and corresponding measures to prevent the sinkhole off the ground, including the causes and impact on society because of this that occurred, and policy measures and abroad are evaluated with respect to what it is.

Study about the Evaluation of Structural Safety for New Conceptual Modular Smart Station (신개념 모듈형 스마트정거장의 구조적 안전성평가에 관한 연구)

  • Lee, Kang-Won;Yoon, Hee-Taek;Park, Young-Kon;Kim, Young-Min;Jo, Chang-Whan
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.251-259
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    • 2009
  • Smart station is a modular one easily installed on the road and protecting from the environmental effects such as snow and rain etc. Smart station can provide some comfortable and easy ambience during waiting the Bimodal Tram. Conventional station can be invaded by overdriven vehicle to make some fatal accident. But smart station gives more protective and safe shelter to the passengers. This paper have investigated and analyzed the structural safety and usefulness about the new conceptual modular smart station.

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The plan of rational span decision to track beam of monorail (모노레일 시스템 궤도빔의 합리적인 경간장 결정방안)

  • Ahn, Yong-Mo;Baek, Cha-Seung
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.199-205
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    • 2008
  • The monorail system as new transportation system mostly has being constructed as an elevated construction and the track beam as mostly main work type occupy the important parts. The structure of monorail system, the track beam support directly vehicle's load and comprised of the track beam structure to be traveling side and understructure to be transmitted from their load to the ground. In particular, in case of construction to elevated structure in the center of a city, it is important to decision plan for span to be considered the economic, execution and maintenance according to transport, installation, and the structure problem, scene and civil appeals to be decided the beam elevation and span. Therefore the standard span of monorail track beam shall be considered the efficient execution, economic and transportation. And propose to reasonable decision plan incorporated the minimizing the road occupied width due to openness to center of a city and bridge pole, minimize to basis size.

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The Change Rate of Vehicle Fuel Consumption for Road Roughness (도로 평탄성 변화에 따른 차량 연료소모량 변화율)

  • Ko, Kwang-Ho;Yoo, In-Kyoon;Lee, Soo-Hyung;Kim, Je-Won
    • 한국방재학회:학술대회논문집
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    • 2010.02a
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    • pp.45.1-45.1
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    • 2010
  • 포장도로의 노화로 인해 도로 표면의 평탄성이 높아지면 차량 주행 시 연료소모량이 증가하는 것으로 알려져 있다. 본 연구에서는 소형/중형/대형의 3개 승용차량에 대해 3가지 평탄도의 도로에서 40~100km/h 의 정속주행 연료소모량을 측정하여 도로 평탄성의 변화에 따른 연료소모량의 변화율을 계산할 수 있었다. 시험결과, 평탄성 증가에 따라 연료소모량이 직선적으로 증가하였으며, 평탄성에 대한 l차 직선방정식으로 연료소모량을 표현할 수 있었다. 평탄성 1m/km 증가 시 연료소모량은 약 80mL/100km 정도의 비율로 증가함을 알 수 있었다. 추후 본 시험의 결과를 이용하여 도로 노화에 따른 연료소모량 증가의 정도를 추정하여 다양한 도로 복구 작업 등에 이용하여 도로에서 발생할 수 있는 사고 예방 등에 활용할 수 있을 것으로 판단된다.

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Development of Cartographic Models for the Resolution of Conflicting Land Use (토지이용의 상충성 해결을 위한 지도학적 모델의 개발)

  • Yi, Gi-Chul
    • Journal of Korean Society for Geospatial Information Science
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    • v.2 no.1 s.3
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    • pp.131-139
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    • 1994
  • Geo-spatial information system technology and cartographic modeling techniques were used as a way to Improve the land use planning process. Off-road vehicle(ORV) trails, timber harvest sites, timber haul mads and wildlife ruffed grouse habitats areas should be allocated together in the Wayne National Forest in the United States. Automated spatial cartographic models were developed to resolve the conflicts of the multiple land use allocation. The techniques of descriptive and prescriptive modeling made the multiple land use allocation efficient and effective.

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A Two-Stage Approach to Pedestrian Detection with a Moving Camera

  • Kim, Miae;Kim, Chang-Su
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.4
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    • pp.189-196
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    • 2013
  • This paper presents a two-stage approach to detect pedestrians in video sequences taken from a moving vehicle. The first stage is a preprocessing step, in which potential pedestrians are hypothesized. During the preprocessing step, a difference image is constructed using a global motion estimation, vertical and horizontal edge maps are extracted, and the color difference between the road and pedestrians are determined to create candidate regions where pedestrians may be present. The candidate regions are refined further using the vertical edge symmetry features of the pedestrians' legs. In the next stage, each hypothesis is verified using the integral channel features and an AdaBoost classifier. In this stage, a decision is made as to whether or not each candidate region contains a pedestrian. The proposed algorithm was tested on a range of dataset images and showed good performance.

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Local Path Planning Manager for Autonomous Navigation of UGV (무인차량의 자율주행을 위한 지역경로계획 매니저)

  • Lee, Young-Il;Lee, Ho-Joo;Park, Yong-Woon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.6
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    • pp.990-997
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    • 2010
  • The Mission environment of UGV(Unmanned Ground Vehicle) has a complexity and variety, and the status of system and sensor is dependent on the environment factors such as operation time, the weather and road type. It is necessary for UGV to cope adaptively with the various mission types, operation modes and operation environment as human operators do. To satisfy this necessity, we present an autonomy manager based on the autonomous architecture. In this paper, we design a path planning software architecture and LPP manager by using open autonomous architecture which is previously designed by ADD. Field test is conducted with UGV in order to verify the performance of LPP Manager based on the Autonomous Architecture with scenarios.

Damage assessment of a bridge based on mode shapes estimated by responses of passing vehicles

  • Oshima, Yoshinobu;Yamamoto, Kyosuke;Sugiura, Kunitomo
    • Smart Structures and Systems
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    • v.13 no.5
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    • pp.731-753
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    • 2014
  • In this study, an indirect approach is developed for assessing the state of a bridge on the basis of mode shapes estimated by the responses of passing vehicles. Two types of damages, i.e., immobilization of a support and decrease in beam stiffness at the center, are evaluated with varying degrees of road roughness and measurement noise. The assessment theory's feasibility is verified through numerical simulations of interactive vibration between a two-dimensional beam and passing vehicles modeled simply as sprung mass. It is determined that the damage state can be recognized by the estimated mode shapes when the beam incurs severe damage, such as immobilization of rotational support, and the responses contain no noise. However, the developed theory has low robustness against noise. Therefore, numerous measurements are needed for damage identification when the measurement is contaminated with noise.

Pareto Optimal Design of the Vehicle Body (차체의 팔렛토 최적 설계)

  • Kim, Byoung-Gon;Chung, Tae-Jin;Lee, Jeong-Ick
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.4
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    • pp.67-74
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    • 2008
  • The important dynamic specifications in the aluminum automobile body design are the vibrations and crashworthiness in the views of ride comforts and safety. Thus, considerable effort has been invested into improving the performance of mechanical structures comprised of the interactive multiple sub-structures. Most mechanical structures are complex and are essentially multi-criteria optimization problems with objective functions retained as constraints. Each weight factor can be defined according to the effects and priorities among objective functions, and a feasible Pareto-optimal solution exists for the criteria-defined constraints. In this paper, a multi-criteria design based on the Pareto-optimal sensitivity is applied to the vibration qualities and crushing characteristics of front structure in the automobile body design. The vibration qualities include the idle, wheel unbalance and road shake. The crushing characteristic of front structure is the axial maximum peak load.