• Title/Summary/Keyword: 차량군

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21세기 보병전투차량(IFV/ICV)의 발전 방향

  • Lee, Sang-Hyeok
    • Defense and Technology
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    • no.3 s.241
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    • pp.76-85
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    • 1999
  • 현대전은 군수면에서의 기술적 우세에 의해 전쟁의 승패가 결정된다는 걸프전의 교훈을 바탕으로, 주요 선진국들은 나름대로의 계획과 형편에 따라 주변기술의 발전과 더불어 21세기를 대비하는 보병전투차량의 연구.개발을 수행하고 있다. 이러한 주요 선진국들의 IFV/ICV의 발전 추세를 철저하게 분석하여, 우리 군의 현 실태와 앞으로의 나아갈 바를 판단할 수 있는 계기를 마련하고, 이에 적극적으로 대처하는 연구.개발 활동과 접근자세가 내부적으로 더욱 필요하다고 판단된다

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Zoom lens design for compact digital camera using lens modules (렌즈모듈을 이용한 컴팩트 디지털 카메라용 줌 렌즈 설계)

  • Park, Sung-Chan;Lee, Sang-Hun
    • Korean Journal of Optics and Photonics
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    • v.16 no.1
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    • pp.34-42
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    • 2005
  • This paper presents the optimum initial design containing the first and third order properties of the three-group zoom system using lens modules, and the real lens design of the system. The optimum initial design with focal length range of 4.3 mm to 8.6 mm is derived by assigning appropriate first and third order quantities to each module along with the specific constraints required for the system. An initial real lens selected for each group has been designed to match its focal length and the first orders into those of the each lens modules, and then combined to establish an actual zoom system by adjusting the air space between the groups at all zoom positions. The combination of the separately designed groups results in a system which satisfies the first order properties of the zoom system composed of the original lens modules. As a result, by residual aberration correction, we could obtain a zoom system useful in compact digital zoom cameras and mobile phone cameras employing the rear focus method.

Development of Two-Lane Car-Following Model to Generate More Realistic Headway Behavior (보다 현실적인 차두시간 행태 구현을 위한 2차로 차량추종모형 개발)

  • Yoon, Byoung Jo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.5
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    • pp.1999-2007
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    • 2013
  • The key characteristics of two-lane-and-two-way traffic flow are platoon and overtaking caused by low-speed vehicle such as truck. In order to develop two-way traffic flow model comprised of CF(car-following) and overtaking model, it is essential to develop a car-following model which is suitable to two-way traffic flow. Short distance between vehicles is caused when a high-speed vehicle tailgates and overtakes foregoing low-speed vehicle on two-way road system. And a vehicle following low-speed vehicle decides to overtake the front low-speed vehicle using suitable space within the headway distribution of opposite traffic flow. For this reason, a two-way CF model should describes not only running within short gap but also headway distribution. Additionally considering domestic two-way-road size, there is a on-going need for large-network simulation, but there are few studies for two-way CF model. In this paper, a two-way CA model is developed, which explains two-way CF behavior more realistic and can be applied for large road network. The experimental results show that the developed model mimics stop-and-go phenomenon, one of features of congested traffic flow, and efficiently generates the distribution of headway. When the CF model is integrated with overtaking model, it is, therefore, expected that two-way traffic flow can be explained more realistically than before.

How to Derive the Autonomous Driving Function Level of Unmanned Ground Vehicles - Focusing on Defense Robots - (무인지상차량의 자율주행 기능수준 도출 방법 - 국방로봇을 중심으로 -)

  • Kim, Yull-Hui;Choi, Yong-Hoon;Kim, Jin-Oh
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.42 no.1
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    • pp.205-213
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    • 2017
  • This paper is a study on the method to derive the functional level required for autonomous unmanned ground vehicle, one of the defense robots. Conventional weapon systems are not significantly affected by the operating environment, while defense robots exhibit different performance depending on the operating environment, even if they are on the same platform. If the performance of defense robot is different depending on operational environment, results of mission performance will be vary significantly. Therefore, it is necessary to clarify the level of function required by the military in order to research and develop most optimal defense robots. In this thesis, we propose a method to derive the required function level of unmanned ground vehicles, focusing on autonomous driving, one of the most vital functions of defense robots. Our results showed that the autonomous driving function depending intervention levels and evaluated functional sensitivity for autonomous driving of the unmanned vehicle using climate and topography as variables.

The Effect of Single-Entry Metering and Platoon Metering on Mainstream under the Same Metering Rate with Pre-timed Metering (정주기식 동일 미터링율 제어에서 차량진입방식에 따른 효과분석)

  • Kim, Sang-Gu;Ryu, Ju-Hyeon
    • Journal of Korean Society of Transportation
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    • v.28 no.3
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    • pp.29-37
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    • 2010
  • Ramp metering control is the most representative strategy of uninterrupted flow control and management system. Ramp metering is to adjust vehicles entering an expressway in such a way that expressway mainline maintains flow stability by regulating ramp vehicles. The effect of two metering strategies, single-entry metering and platoon metering, on mainstream under the same metering rate with pre-timed metering are analyzed by micro-simulation. Platoon metering shows lower performance than single-entry metering under the same metering rate in terms of speed, density, and delay, causes earlier breakdown than single-entry metering. It indicates that the selection of metering type has critical importance as the flow of mainline is high.

Impacts of Automated Vehicle Platoons on Car-following Behavior of Manually-Driven Vehicles (군집주행 환경이 비자율차량의 차량 추종에 미치는 영향분석)

  • Suh, Sanghyuk;Lee, Seolyoung;Oh, Cheol;Choi, Saerona
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.4
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    • pp.107-121
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    • 2017
  • This study conducted a 3-stage survey and simulation experiment to identify the impact of vehicle platoons on car-following behavior of manually-driven vehicles. Vehicle maneuvering data obtained from driving simulations was statistically analyzed based on three measures including average speed, acceleration noise, and offset to represent the deviation of lateral movements. Results indicate that MV drivers tended to have psychological burden while driving in automated vehicle platooning environments, which resulted in different vehicle maneuvers. It is expected that the outcome of this study would be useful fundamentals in developing various traffic operations strategies for managing mixed traffic stream consisting of MVs and autonomous vehicles.

Study on The Warranty of Opposing Through Flow Gap Acceptance Time for more Efficient Management of Permissive Left-Turn (비보호 좌회전 효율성 제고를 위한 대향 직진 교통류의 Gap-Time기준 연구)

  • Baik, Seung-Yup;Park, Ki-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.107-115
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    • 2011
  • Since 2009 The Korean National Police Agency has been pushed "permissive left-turn" forward in order to making progress in Korean traffic operations system. Preceding researches manuals and guidelines present 6 standards(# of accidents # of lanes, pedestrian volume sight # of permissive left-turn lanes vehicle volume) as installation permissive left-turn. But in practical affairs it is most important that secure enough Gap-time between permissive left-turn vehicle and opposite through lane vehicle to make permissive left-turn vehicle move safer and more efficiently. This study suggests applying gap acceptance theory in microscopic model to permissive left-turn installation standards. Analysis methods of this study are field data survey statistical analysis and microscopic simulation analysis. This study collected field data by using AVI recording and measured permissive left-turn vehicle intersection passing time(T1) and against the opposite through lane vehicle Gap-time(T2). And statistical analysis performed about two values that measured before to predict the functionality between T1 and T2. These studies to overcome the limit of sample size carried out a microscopic simulation(VISSIM) plan and collect more samples to input statistical analysis.

A License Plate Recognition Algorithm using Multi-Stage Neural Network for Automobile Black-Box Image (다단계 신경 회로망을 이용한 블랙박스 영상용 차량 번호판 인식 알고리즘)

  • Kim, Jin-young;Heo, Seo-weon;Lim, Jong-tae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.1
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    • pp.40-48
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    • 2018
  • This paper proposes a license-plate recognition algorithm for automobile black-box image which is obtained from the camera moving with the automobile. The algorithm intends to increase the overall recognition-rate of the license-plate by increasing the Korean character recognition-rate using multi-stage neural network for automobile black-box image where there are many movements of the camera and variations of light intensity. The proposed algorithm separately recognizes the vowel and consonant of Korean characters of automobile license-plate. First, the first-stage neural network recognizes the vowels, and the recognized vowels are classified as vertical-vowels('ㅏ','ㅓ') and horizontal-vowels('ㅗ','ㅜ'). Then the consonant is classified by the second-stage neural networks for each vowel group. The simulation for automobile license-plate recognition is performed for the image obtained by a real black-box system, and the simulation results show the proposed algorithm provides the higher recognition-rate than the existing algorithms using a neural network.

Improvement of Hill Climbing Ability for 6WD/6WS Vehicle using Optimum Tire Force Distribution Method (최적 타이어 힘 분배를 이용한 6WD/6WS 차량의 등판 주행 성능 향상)

  • Kim, Sang-Ho;Kim, Chang-Jun;Han, Chang-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.4
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    • pp.1523-1531
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    • 2011
  • Multi-axle driving vehicle are favored for military use in off road operations because of their high mobility on extreme terrains and obstacles. Especially, Military Vehicle needs an ability to driving on hills of 60% angle slope. This paper presents the improvement of the ability of hill climbing for 6WD/6WS vehicle through the optimal tire force distribution method. From the driver's commands, the desired longitudinal force, the desired lateral force, and the desired yaw moment were obtained for the hill climbing of vehicle using optimal tire force distribution method. These three values were distributed to each wheel as the torque based on optimal tire force distribution method using friction circle and cost function. To verify the performance of the proposed algorithm, the simulation is executed using TruckSim software. Two vehicles, the one the proposed algorithm is implemented and the another the tire's forces are equivalently distributed, are compared. At the hill slop, the ability to driving on hills is improved by using the optimum tire force distribution method.

Research of Usability Test on Disabled Welfare Vehicle for Guardians and Passengers of Disabled People (장애인 보호자 및 탑승자를 대상으로 한 장애인 복지차량 사용성 평가 연구)

  • Rhee, Kun Min;Kim, Dong Ok
    • 재활복지
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    • v.20 no.3
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    • pp.141-161
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    • 2016
  • This research is to anticipate problems of Ray's disabled experiment welfare vehicles for 17 drivers with disability, improving them. In addition it is to provide the criteria for ergonomic design based on perspective of drivers with disability by investigating 18 items of usability test. The results are as follows. First, satisfaction degree of Ray, disabled experiment welfare vehicle, was shown to be 3.88 which is higher than normal vehicles whose degree is 3.20. This showed that the disabled experiment welfare vehicle is the one with much improvement. Second, so as to develop a welfare vehicle it needs to take into account some factors including rear slope, wheelchair locker, seat belt, safety grip, and high roof. Third, in case of rear slope, high roof and width of manual or automatic wheel chairs should be considered and motor-operated device should also be taken into account for safety lockers, which make a wheelchair firmly fixed. Moreover, motor-operated seat and rear slope can be chosen for either of the disabled and the elderly.