• Title/Summary/Keyword: Off-The-Road

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A Study on the Development of No Spin Differential for an Off-road Vehicle (야지 차량용 No Spin Differential 개발에 관한 연구)

  • 편영식;장영도;이영춘;박정현;여진욱
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.6
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    • pp.127-133
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    • 2003
  • NSD(No Spin Differential) has been developed fer a military truck. A benchmarking study for USA and Russian NSD has been carried out. Axiomatic approach has been applied for improving the design. A test code for NSB has been developed and applied to the developed sample. In the test results of comparing the developed sample with the USA imported sample, three major characteristics-the noise, mobility and steerability - are in the range of the intended target. A practical process for the evolution design is proposed.

Computer simulation for the Prediction of Mobility and Tractive Performance of Tracked Vehicles (궤도형 로외차량의 주행 및 견인 성능 예측 컴퓨터 시뮬레이션)

  • 김경욱;신범수;김채주
    • Transactions of the Korean Society of Automotive Engineers
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    • v.2 no.3
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    • pp.105-112
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    • 1994
  • A computer program was developed for the simulation of mobility and tractive performance of tracked off-road vehicles. Input parameters for the simulation involve those characterizing track and power drive line of a vehicle and soil conditions upon which the vehicle operates. The simulation predicts tractive performance in terms of soil thrust and motion resistance of track device and mobility performance in terms of the maximum speed, time-distance and time-speed relation that a vehicle can obtain under the given soil conditions. It also determines whether or not the vehicle can move in those conditions. An example of performing simulation was presented and its results showed that the performance prediction was reasonably in a good agreement with the published data.

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LED Street Light Lamp Control by Central Command System (중앙관제시스템에 의한 LED 도로조명제어)

  • Cho, Si-Hyeong;Park, Chan-Won
    • Journal of Industrial Technology
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    • v.30 no.B
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    • pp.75-81
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    • 2010
  • This paper presents the development of LED street light lamp which is controled by central command system. This system includes a lamp unit controller, data repeater and command repeater as well as the LED lamps. These devices enable the individual power control and partial on/off control of the LED lamps by the control repeater through full duplex communication line. Also, they have the ability to control the brightness and period of on/off timing by detecting the car's existence. As a result of this development, it is founded that the performances of the system have been satisfied to apply for the actual road test.

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A New Driving Mechanism to Allow a Rescue Robot to Climb Stairs

  • Lim, Sung-Kyun;Park, Dong-II;Kwak, Yoon-Keun
    • International Journal of Precision Engineering and Manufacturing
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    • v.8 no.3
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    • pp.3-7
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    • 2007
  • There have been numerous studies directed toward the development of driving mechanisms for off-road mobility and rescue robots. To achieve surveillance, reconnaissance, and rescue, it is necessary for robots to have a driving mechanism that can handle off-road environments, We propose a new type of single-track driving mechanism with a variable geometry for a rescue robot, This mechanism has a symmetric configuration so that the robot can advance in two directions and also remain operable when overturned. By transforming its geometry, the robot can reduce energy consumption in steering and rotating as well as maximize its ability to climb obstacles such as stairs. The robot is also designed to have a compact size and low center of gravity to facilitate driving when on a set of stairs. In this paper, we analyzed the design parameters of the robot for the four phases of climbing stairs and determined the specifications needed to enhance its adaptability.

Performance Analysis of Optical Path Difference on Visible Light Communication System for Intelligent Transport Systems

  • Choi, Jae-Hyuck;Lee, Kye-San;Cha, Jae-Sang;Kim, Jin-Young
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.5
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    • pp.114-120
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    • 2009
  • In outdoor visible light communication channels and LED road illumination communications for the intelligent transport systems (ITS), inter symbol interference (ISI) due to multipath propagation prevents high data rate transmission. Indoor wireless optical communication systems utilizing white LED lights and on the road illumination have been studying about it. Generally, plural lights are installed in room and considered to the traffic information system using existing LED traffic lights. Therefore, their optical path difference must be considered. In this paper, the influence of an optical path difference has been investigated and two approaches against this problem are introduced. One uses on-off keying, return-to-zero (OOK-RZ) coding and the other uses optical orthogonal frequency division multiplexing(OFDM).

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A Study on Performance Characteristics in a LPG Fueled Engine (LPG 연료기관의 성능특성에 관한 연구)

  • Cho, K.H.;Baek, T.S.;Paek, Y.;Lee, J.T.
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1203-1210
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    • 2001
  • This study was carried out to develop an engine for off-road vehicles especially for farm tractors using the liquefied petroleum gas (LPG) which is known as a source of energy having good potential of substitute fuel for diesel engine because of its economical advantage and low pollutant materials after combustion. The study was focused on develop an engine of high in specific power output, low in specific fuel consumption and emission of pollutants. A series of teat was dope on the engine - various laboratory tests to analyze performance of the engine and actual field tests with the engine installed on a farm tractor as a power source.

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A Study of Real-time Semantic Segmentation Performance Improvement in Unstructured Outdoor Environment (비정형 야지환경 주행상황에서의 실시간 의미론적 영상 분할 알고리즘 성능 향상에 관한 연구)

  • Daeyoung, Kim;Seunguk, Ahn;Seung-Woo, Seo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.25 no.6
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    • pp.606-616
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    • 2022
  • Semantic segmentation in autonomous driving for unstructured environments is challenging due to the presence of uneven terrains, unstructured class boundaries, irregular features and strong textures. Current off-road datasets exhibit difficulties like class imbalance and understanding of varying environmental topography. To overcome these issues, we propose a deep learning framework for semantic segmentation that involves a pooled class semantic segmentation with five classes. The evaluation of the framework is carried out on two off-road driving datasets, RUGD and TAS500. The results show that our proposed method achieves high accuracy and real-time performance.

Vision Based Outdoor Terrain Classification for Unmanned Ground Vehicles (무인차량 적용을 위한 영상 기반의 지형 분류 기법)

  • Sung, Gi-Yeul;Kwak, Dong-Min;Lee, Seung-Youn;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.4
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    • pp.372-378
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    • 2009
  • For effective mobility control of unmanned ground vehicles in outdoor off-road environments, terrain cover classification technology using passive sensors is vital. This paper presents a novel method far terrain classification based on color and texture information of off-road images. It uses a neural network classifier and wavelet features. We exploit the wavelet mean and energy features extracted from multi-channel wavelet transformed images and also utilize the terrain class spatial coordinates of images to include additional features. By comparing the classification performance according to applied features, the experimental results show that the proposed algorithm has a promising result and potential possibilities for autonomous navigation.

Multi-Layer Bitcoin Clustering through Off-Chain Data of Darkweb (다크웹 오프체인 데이터를 이용한 다계층 비트코인 클러스터링 기법)

  • Lee, Jin-hee;Kim, Min-jae;Hur, Junbeom
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.31 no.4
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    • pp.715-729
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    • 2021
  • Bitcoin is one of the cryptocurrencies, which is decentralized and transparent. However, due to its anonymity, it is currently being used for the purpose of transferring funds for illegal transactions in darknet markets. To solve this problem, clustering heuristic based on the characteristics of a Bitcoin transaction has been proposed. However, we found that the previous heuristis suffer from high false negative rates. In this study, we propose a novel heuristic for bitcoin clustering using off-chain data. Specifically, we collected and analyzed user review data from Silk Road 4 as off-chain data. As a result, 31.68% of the review data matched the actual Bitcoin transaction, and false negatives were reduced by 91.7% in the proposed method.

The Study on Parking Lots Management according to Off-Street Parking Lots Characteristics : Focusing on Residential Development District (노외주차장 특성이 주차장 운영여부에 미치는 영향분석 : 택지사업지구를 중심으로)

  • Kim, Tae-Gyun;Byun, Wan-Hee;Lee, Yun-Sang
    • Land and Housing Review
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    • v.8 no.3
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    • pp.131-143
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    • 2017
  • Automobiles and parking lots have greatly been increased by the continuous development of new towns and residential districts. There were not enough parking lots; and although there were off-street parking lots available for sale, they were not easily sold. Through a parking regulation, local governments can require parking spaces for more than a certain rate in developing areas. Despite local governments should require parking spaces within the parking demand and regulation, they did not investigate parking demands. Off-street parking spaces are not easy to sell because they don't consider the parking demand. In this study, we analyzed the factors that affect the parking management in order to increase sales of the off-street parking. The factors were "the characteristics of the parking lots", "the accessibility of the off-street parking", and "the traffic environment around off-street parking." We have derived suggestions for these factors. In addition, this study has derived nine variables affecting the parking operation in these three factors, and suggested a logistic regression model and the influence of each factors. According to the analysis, "parking signs" were the most influential. Next were "land uses" and "lanes on road".