• Title/Summary/Keyword: 크레임

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Experimental Study on Fatigue Crack in Welded Crane Runway Girders(I) -Initiation and Propagation of Fatigue Crack- (크레인 거더의 피로균열에 관한 실험적 연구(I) -피로균열의 발생과 진전-)

  • Im, Sung Woo;Kim, Jin Ho;Chang, In Hwa;Shinga, Atsumi
    • Journal of Korean Society of Steel Construction
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    • v.9 no.2 s.31
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    • pp.237-248
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    • 1997
  • Three types of fatigue cracks frequently observed in the crane runway girders are verified experimentally using two testing-purpose girders with the size of $6400{\times}600{\times}300$ in millimeters. The fatigue cracks are observed in the vicinity of load-bearing points, at the end of gusset plates and at the fillet welded joints between the lower flange and the web. The load-bearing-point cracks are initiated at the intersection of the fillet welds between the upper flange and the web, where the vertical stiffener is located. The cracks grow up toward the diagonal direction of the web. The cracks observed at the fillet welded joints grow up perpendicularly to the crane runway girder. Compared with the JSSC fatigue design code, the joint class is classified as follows: E for the vicinity of load-bearing points, G or H for the end of gusset plates and D for the lower fillet welded joints. The tests reveal that the class of joint classification at the end of gusset plates and at the lower flange coincides with the fatigue design code.

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Development of Infrared-Ray Communication System for Position Recognition of Yard Tractor in Container Terminal (컨테이너터미널 내의 야드 트랙터 위치인식을 위한 적외선 통신시스템 개발)

  • Hong, Dong-Hee;Kim, Chang-Gon
    • Journal of Digital Convergence
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    • v.11 no.1
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    • pp.211-223
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    • 2013
  • In Korea, the location of yard tractors is figured out in real time by using RFID system in container terminals. However, even though the location recognition of RFID system works fine when transfer crane is in yard operation, there are some problems when container crane is in ship operation. That is because yard tractors come one by one to each transfer crane in an order, but yard tractors come in 4 lanes to the container crane, which makes the system impossible to recognize each yard tractor separately. Therefore, we developed the infrared-ray communication system which can recognize yard tractors accurately in not only in the yard operation of transfer crane but also in the ship operation of container crane in same way in this study. The result in this study showed constant number of recognition, and the range of recognition measures 5.7m in 25m distance. The range of recognition shown in this study is enough to recognize each yard tractor passing under container crane separately.

Real Time Scheduling for Multiple Yard Cranes in an Automated Container Terminal (자동화 컨테이너 터미널의 복수 장치장 크레인을 위한 실시간 작업 계획 수립)

  • Park, Tae-Jin;Choe, Ri;Ryu, Kwang-Ryel
    • Journal of Navigation and Port Research
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    • v.31 no.10
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    • pp.869-877
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    • 2007
  • This paper proposes a realtime scheduling method using local search algorithm for non-crossable yard cranes in automated container terminal. To take into consideration the dynamic property of yard crane operation and satisfy the real time constraint, the proposed method repeatedly builds crane schedule for the jobs in a fixed length look-ahead horizon whenever a new job is requested In addition, the proposed method enables the co-operation between yard cranes through prior re-handling and re-positioning in order to resolve the workload imbalance problem between the two cranes, which is one of the primary causes that lower the performance of yard cranes. Simulation-based experiments have shown that the proposed method outperforms the heuristic based methods, and the cooperation scheme contributes a lot to the performance improvement.