• Title/Summary/Keyword: TURN

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A search on the Impossible Turn for Pilots (조종사에 있어서 Impossible Turn에 관한 고찰)

  • Song, Byung-Heym
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.2
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    • pp.183-190
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    • 1994
  • 본 연구에서는 항공기 사고의 대부분을 차지하는 이${\cdot}$착륙단계중에서, 이륙직 후 저고도에서 동력이 상실되었을 경우에 이륙활주로 방향으로 Turning Back하는 것은, 어떠한 안전 한계를 지니고 있는지를 선회 소요시간과 고도손실, 선회율과 활공속도와의 관계 등의 이론적인 근거에 기초하여 분석하고자 한다.

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The computation of the turn-over time by meteorologically-induced circulation on the East China Sea (계절별 풍성류에 의한 동지나해의 해수 교체시간 산정)

  • 최병호;서경석
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1991.07a
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    • pp.77-81
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    • 1991
  • 3차원 수치모형(Choi, 1989)을 이용하여 동지나해의 계절별 및 연평균의 풍성류 순환을 산정하였고, 이률 사용하여 동지나해의 분할된 여러 영역에서 수심별 해수 교체시간(turn-over time)을 계산하였다.(중략)

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Turn-Tree Derrick (턴트리 데릭크)

  • Y.J.,Ha
    • Bulletin of the Society of Naval Architects of Korea
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    • v.18 no.3
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    • pp.59-63
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    • 1981
  • With substitution with a delicate turn-tree instead of a long permanent cross-tree that is usally located on the derrick post, it is possible to get a large working range of the slewing angle 240 degree and also to decrease the slewing time of the derrick boom, comparing to the exisiting cargo gear system which has the same capacity of slewing winch.

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Detection of Illegal U-turn Vehicles by Optical Flow Analysis (옵티컬 플로우 분석을 통한 불법 유턴 차량 검지)

  • Song, Chang-Ho;Lee, Jaesung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.10
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    • pp.948-956
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    • 2014
  • Today, Intelligent Vehicle Detection System seeks to reduce the negative factors, such as accidents over to get the traffic information of existing system. This paper proposes detection algorithm for the illegal U-turn vehicles which can cause critical accident among violations of road traffic laws. We predicted that if calculated optical flow vectors were shown on the illegal U-turn path, they would be cause of the illegal U-turn vehicles. To reduce the high computational complexity, we use the algorithm of pyramid Lucas-Kanade. This algorithm only track the key-points likely corners. Because of the high computational complexity, we detect center lane first through the color information and progressive probabilistic hough transform and apply to the around of center lane. And then we select vectors on illegal U-turn path and calculate reliability to check whether vectors is cause of the illegal U-turn vehicles or not. Finally, In order to evaluate the algorithm, we calculate process time of the type of algorithm and prove that proposed algorithm is efficiently.

Evaluation of Mobility and Safety of Operating an Overlap Phase on a Shared-Left-Turn Lane Using a Microscopic Traffic Simulation Model (미시교통시뮬레이션모형을 이용한 공용 좌회전 차로의 중첩현시운영의 이동성과 안전성 평가 연구)

  • Yun, Il-Soo;Han, Eum;Woo, Seok-Cheol;Yoon, Jung-Eun;Park, Sung-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.5
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    • pp.15-26
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    • 2012
  • Government agencies including the national police agency have executed diverse efforts including continuous improvements of traffic facilities and operation methods, education, enforcements in order to improve traffic operation systems; nevertheless there have been continuous criticisms on irrationality in traffic signal and road facility operation. One of the reasons may be the lack of systematic preliminary evaluations on various alternatives. However, there was no appropriate tool to evaluate the mobility and safety of thus alternatives in a systematic way. Therefore, this study proposes the systematic use of microscopic traffic simulation models as a comprehensive evaluation tool. In addition, this study verified the potential of using a microscopic traffic simulation model using the case of operating an overlap phase on a shared-left-turn lane through a systematic way where the evaluation was conducted through data collection, building networks, calibrating microscopic simulation models, producing performance measures, evaluating mobility and safety, and so on. As a result, the operation of overlap phase on a shared-left-turn lane showed no big difference from other operation scenarios such as leading left-turn on exclusive left turn lane in terms of mobility. However the operation of overlap phase on a shared-left-turn lane decreased safety by increasing potential conflicts.

A Study on Determining the Optimal Size of Bicycle Waiting Zone under Hook-Turn Operation (Hook-Turn 통행방식의 적정 자전거 대기공간 크기 결정에 관한 연구)

  • Lim, Guk-Hyun;Kim, Nam-Sun;Lee, Sang-Soo;Nam, Doohee;Kim, Jeong-Tae
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.5
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    • pp.42-53
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    • 2016
  • This study aims to evaluate the performance of Hook-turn operation with various sizes of bicycle waiting zone(WZ) and to determine the optimal size of bicycle WZ under various traffic and control circumstances. An extensive simulation study was performed to examine bicycle and vehicle delay trends for given experimental design. Results showed that vehicle delay was insensitive to the size of waiting zone, but bicycle delay was reduced as the size of waiting zone increased in general. The delay performance indicated a similar trend between with RTOR and without RTOR operation, but vehicle delay slightly increased and bicycle delay slightly decreased without RTOR. Regarding to optimal waiting zone size, 6 WZ was recommended for general conditions with RTOR, but 9 WZ was recommended when bicycle left-turn volume was greater than 120 v/h. 6 WZ was recommended for general conditions without RTOR, but 12 WZ was recommended when bicycle left-turn volume was greater than 90 v/h.

Kinematical Analysis of Basket with 1/2 Turn to Handstand on Parallel Bars (평행봉 Basket with 1/2 Turn to Handstand 기술 분석)

  • Back, Jin-Ho;Park, Jong-Chul;Lee, Yong-Sik
    • Korean Journal of Applied Biomechanics
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    • v.17 no.1
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    • pp.165-174
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    • 2007
  • The subject of this study was male apparatus gymnastics athlete who had scored high points doing basket with 1/2 turn on parallel bars. Then 3D motion analysis were used to calculate & analyse kinematic variables of Basket with 1/2 turn to Handstand. 1. The total average time spent for Basket with 1/2 turn took $2.16{\pm}.08sec$, at the downward upward phase took $.58{\pm}0.00sec$, $.23{\pm}.00sec$, at flight phase took $.28{\pm}.01sec$, at connected area phase took $.72{\pm}0.21sec$, at rotation area phase took $.35{\pm}.14sec$. To have a successful performance, there should be faster speed and velocity to rotate at the downward upward phase, then the upward velocity and height must be used adequately. Moreover, the speed must be faster at the flight connect phase to stabilize Center of Mass(CM) for the body, and must secure more time at the rotation area to have more stable performance. 2. After handstand on parallel bars while moving CM to right hand side, and It must be performed with big and magnificent performance with putting both hand's center to far away from the parallel bars. 3. Furthermore, CM must be moved fast from downwards to right hand side, and CM must be moved fast in vertical movement at upward and flight phase to avoid CM from moving back and forth, and left and right. 4. At downwards, the subject must rotate as bis as possible using hip-joint as wide as possible and at upwards, must put his body to vertical to have stable performance. While rotating or turning, it is better to do with bigger shoulder angle and have to make sure that trunk angle must be not scattered. To perform better and more positive in basket with 1/2 turn on parallel bars, the centrifugal force must be used big and fast at downward, and at upward and flight phase, downward movement must change to vertical movement as soon as possible while turning movement must happen at handstand position. Time spent must be shorten at connected area to stabilize CM and turning must be natural as possible while securing the necessary time of movement to well-balanced. Also, the body must be vertically closed from the ground.

Development of Left Turn Response System Based on LiDAR for Traffic Signal Control

  • Park, Jeong-In
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.11
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    • pp.181-190
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    • 2022
  • In this paper, we use a LiDAR sensor and an image camera to detect a left-turning waiting vehicle in two ways, unlike the existing image-type or loop-type left-turn detection system, and a left-turn traffic signal corresponding to the waiting length of the left-turning lane. A system that can efficiently assign a system is introduced. For the LiDAR signal transmitted and received by the LiDAR sensor, the left-turn waiting vehicle is detected in real time, and the image by the video camera is analyzed in real time or at regular intervals, thereby reducing unnecessary computational processing and enabling real-time sensitive processing. As a result of performing a performance test for 5 hours every day for one week with an intersection simulation using an actual signal processor, a detection rate of 99.9%, which was improved by 3% to 5% compared to the existing method, was recorded. The advantage is that 99.9% of vehicles waiting to turn left are detected by the LiDAR sensor, and even if an intentional omission of detection occurs, an immediate response is possible through self-correction using the video, so the excessive waiting time of vehicles waiting to turn left is controlled by all lanes in the intersection. was able to guide the flow of traffic smoothly. In addition, when applied to an intersection in the outskirts of which left-turning vehicles are rare, service reliability and efficiency can be improved by reducing unnecessary signal costs.