• Title/Summary/Keyword: vehicle shape

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Real Time Multiple Vehicle Detection Using Neural Network with Local Orientation Coding and PCA

  • Kang, Jeong-Gwan;Oh, Se-Young
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.636-639
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    • 2003
  • In this paper, we present a robust method for detecting other vehicles from n forward-looking CCD camera in a moving vehicle. This system uses edge and shape information to detect other vehicles. The algorithm consists of three steps: lane detection, ehicle candidate generation, and vehicle verification. First after detecting a lane from the template matching method, we divide the road into three parts: left lane, front lane, and right lane. Second, we set the region of interest (ROI) using the lane position information and extract a vehicle candidate from the ROI. Third, we use local orientation coding (LOC) edge image of the vehicle candidate as input to a pretrained neural network for vehicle recognition. Experimental results from highway scenes show the robustness and effectiveness of this method.

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Dynamic Performance Evaluation of Concrete Barrier Systems for Small Vehicle Roadway (소형차 전용도로를 위한 콘크리트 차량방호울타리의 동적성능 평가)

  • Hwang, In-Tae;Lee, Dong-Woo;Choi, Hyun-Ho;Woo, Kwang-Sung
    • International Journal of Highway Engineering
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    • v.14 no.4
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    • pp.113-124
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    • 2012
  • PURPOSES : In This study two different concrete barrier systems have been proposed to be established at the small vehicle driveway. One is for median barrier, and the other is for roadside barrier. METHODS : In order to determine the suitable shape of barrier, the impact parameters including vehicle weight, impact angle, impact velocity and impact level have been analyzed. The real crash test has been carried out with 0.9 ton and 2.5 ton vehicles, respectively by using the 2m segment type concrete barriers connected by steel plates that are totally 40m barrier systems. RESULTS : The numerical results obtained by LS/DYNA-3D software are compared with real crash tests from the viewpoints of vehicle stability, vehicle trajectory, occupant risk, etc. CONCLUSIONS : From the above results, the dynamic performance of proposed barrier systems satisfies the specification of Korean Code for roadside safety structures.

Improved Prediction of Lift-off Acoustic Loads for a Launch Vehicle (발사체 이륙 시 음향 하중 예측 정확도 향상)

  • Choi, Sang-Hyeon;Ih, Jeong-Guon;Lee, Ik-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.04a
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    • pp.207-210
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    • 2014
  • This paper is concerned with the prediction of lift-off acoustic loads for a launch vehicle. Intense acoustic load is generated when a launch vehicle is lifted off, and it can induce vibrations of a launch vehicle which cause damage or malfunction of a launch vehicle and a satellite. Lift-off acoustic loads of NARO are predicted by the modified Eldred's second method and the result is compared with the measured data in flight test. The prediction shows similar peak and shape of spectrum to the test data, but some discrepancy can be observed due to the predicted margin. In order to reduce such discrepancy, the sound pressure levels with four source distribution assumptions are calculated. Also, the surface diffraction effects are considered in the predict ion of lift-off acoustic loads, and the predicted result is more similar to the test data.

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Speed Estimation from Tire Marks for Vehicle Accident Reconstruction (곡선 형태의 타이어 자국으로부터 차량사고시 속도추정)

  • Kim, Min-Seok;Lee, Ji-Hoon;Yoo, Wan-Suk;Kim, Kee-Nam
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.5
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    • pp.128-133
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    • 2008
  • In this paper, a new technique was suggested to estimate vehicle speed for the traffic accident reconstruction, and accident investigators can estimate initial vehicle speed based on this suggested technique. Turning tests with several vehicle speeds were executed and compared with the motion of the vehicle and the shape of the tire marks. A new method for estimating the coefficient of friction is suggested by using the longitudinal and lateral components of tire marks. And also, a speed calculation graph is suggested to estimate vehicle speed for traffic accident reconstruction.

Detection of Dumping Position Using Vehicle Tracking (차량 트레킹을 통한 매립위치의 검출)

  • Lee, Dong-Gyu;Lee, Young-Dae;Cho, Sung-Yun
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2012.07a
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    • pp.433-434
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    • 2012
  • In this paper, we developed the algorithm which tracking the vehicle and deciding the moment of dumping in landfills. We first trace the position of vehicle using the difference image between current image and background image and then we decide the stop point from the shape of vehicle route and detect the dumping point by comparing the dumping image with the image that vehicle is stopping.

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Bridge modal identification based on frequency variation caused by a parked vehicle

  • He, Wen-Yu;Ren, Wei-Xin;Wang, Quan;Wang, Zuo-Cai
    • Structural Engineering and Mechanics
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    • v.84 no.3
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    • pp.413-421
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    • 2022
  • Modal parameters are the main dynamic characteristics of bridge. This study aims to propose an innovative route to estimate the modal parameters for bridges by using a parked vehicle in which mode shapes with high accuracy and spatial resolution are identified by frequency measurement. Based on the theory of dynamic modification and modal identification, the mathematical formulation between the parked mass induced frequency variation and the modal parameters of a bridge is derived. Then this mathematical formulation is extended to a parked vehicle-bridge system. The arithmetic and processes for estimating the modal parameters based on the identified frequency variation of the vehicle-bridge systems when the vehicle locates at sequentially arranged positions are presented. Finally the proposed method is applied to several simulated bridges of different types. The results indicate that it can estimate the modal parameters with high accuracy and efficiency.

The Development of Seat Track Parts Using Shape Freeze in UHSS (초고강도 소재 성형시 형상 동결을 이용한 Seat Track 부품 개발)

  • Park, Dong Hwan;Yun, Jae Jung;Moon, Hyun Duk;Lee, Tae Gil
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.26 no.1
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    • pp.59-65
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    • 2017
  • A seat track product is a car seat part that provides a base for vehicle seats. An ultra-high strength steel sheet is used to reduce the weight of vehicle body parts. However, the formability of an ultra-high strength steel sheet is poor because of its very low elongation and very high elastic deformation. For this reason, a new forming technology of an ultra-high strength steel sheet is required. The influence of spring-back of seat track parts on the shape freeze in forming processes was investigated to be solved by adjusting the appropriate tool design such as minus clearance between punch and die, and punch angle. This paper describes how to apply the spring-back prevention technique for improving shape freeze by using the ultra-high strength steel sheet with 980MPa to develop lightweight seat tract parts.

Numerical Analysis of Axisymmetric Supercavitating Underwater Vehicle with the Variation of Shape Parameters (축대칭 수중 운동체의 형상 변화를 고려한 초월공동 수치해석)

  • Park, Hyun-Ji;Kim, Ji-Hye;Ahn, Byoung-Kwon
    • Journal of the Society of Naval Architects of Korea
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    • v.55 no.6
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    • pp.482-489
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    • 2018
  • Most of the numerical and experimental studies on supercavitating flows are focused on the cavitator only. However, the partial cavity growing into the supercavity is affected by the shape of the body placed behind the cavitator. In this paper, we develope a numerical method which is based on the boundary element method to predict supercavitating flow around three-dimensional axisymmetric bodies. We estimate the influence of the body shape on the supercavity growth. Here, we consider various parameters of the body such as cavitator shape, shoulder length and body diameter, and compare the results with the case of the cavitator only. In summary, it is found that the body may impede the cavity growth, the shoulder mainly affects the cavity length, and the supercavity occurring in the cone type cavitator is strongly influenced rather than that of the disk type cavitator.

Convergence Technique Study of Durability Analysis due to the Track Pad Shape of Track Vehicle with Heavy Weight (중량 궤도차량의 궤도 패드형상에 따른 내구성 해석의 융합 기술 연구)

  • Lee, Jung-Ho;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.7 no.1
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    • pp.177-182
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    • 2016
  • In order that the track vehicle utilized on the purpose of heavy industry and military affair may endure the vehicle body with heavy weight, the link surrounding the mobile wheel is affected with the great force by the load transferred at the vehicle body. This happened force gives rise to a decline in the durability throughout the track. In this paper, the models with the shapes of track pads in common use are designed and the model at which the wear of track pad and the damage of link can be decreased effectively is contrived. Also, by applying this study result to the design of track vehicle, it can contribute to the safe design for damage prevention and durability improvement. It is possible to be grafted onto the convergence technique at the designed factor of pad shape and show the esthetic sense.

Implementation of Preceding Vehicle Break-Lamp Detection System using Selective Attention Model and YOLO (선택적 주의집중 모델과 YOLO를 이용한 선행 차량 정지등 검출 시스템 구현)

  • Lee, Woo-Beom
    • Journal of the Institute of Convergence Signal Processing
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    • v.22 no.2
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    • pp.85-90
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    • 2021
  • A ADAS(Advanced Driver Assistance System) for the safe driving is an important area in autonumous car. Specially, a ADAS software using an image sensors attached in previous car is low in building cost, and utilizes for various purpose. A algorithm for detecting the break-lamp from the tail-lamp of preceding vehicle is proposed in this paper. This method can perceive the driving condition of preceding vehicle. Proposed method uses the YOLO techinicque that has a excellent performance in object tracing from real scene, and extracts the intensity variable region of break-lamp from HSV image of detected vehicle ROI(Region Of Interest). After detecting the candidate region of break-lamp, each isolated region is labeled. The break-lamp region is detected finally by using the proposed selective-attention model that percieves the shape-similarity of labeled candidate region. In order to evaluate the performance of the preceding vehicle break-lamp detection system implemented in this paper, we applied our system to the various driving images. As a results, implemented system showed successful results.