• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.40-47
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• 2002

농산물의 품질은 생산자에서 최종 소비자에게 도착될 때까지의 일련의 취급과정에서 발생되는 생리적, 환경요인에 의해 좌우되며 단 한번의 부주의에 의한 취급도 바로 품질저하로 연결되는 되돌릴 수는 없는 나쁜 결과를 만든다. 청과류는 수송과 취급기간 중에 충격, 마찰, 눌림, 타박 등에 지속적으로 노출된다. 그러므로 농산물의 품질을 저하시키는 물리적인 손상을 최소화하기 위해 최선의 처리와 수송방법을 선택할 필요가 있다. (중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.233-235
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• 2007

현재 기존 철송 시스템에 있어서 문제점인 출발지와 목적지 사이 발생하는 복잡한 작업 프로세스(job process)를 간소화하여 철송 운임비감소와 물류운송의 체계 개선 및 활성화에 기여할 수 있는 시스템으로 DMT(Dual Mode Trailer) 시스템을 들 수 있다. 이에 본 기술의 국내적용 및 개발을 위해 기술동향 조사 및 국내 적용시 고려사항, 국내 적용 접합 모델 도출 등 그 기술성을 분석하였다.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.629-636
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• 2008

Dual Mode Trailer(DMT) systems are significantly considered as future transportation technique particularly to eliminate complicated job process in the railroad based transportation and reduce relevant logistic cost in economic viewpoint. This paper presents survey of Dual Mode Trailer(DMT) systems in terms of technical applicability in domestic industry, technical trends, etc. We provide several DMT systems addressed until now and propose suitable framework of them to our nation.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.9
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• pp.717-722
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• 2001

This paper presents a methodology on the backward path tracking control of a trailer type robot which consists of two parts: a tractor and a trailer. It is difficult to control the motion of a trailer vehicle since its dynamics is non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a real-coded genetic algorithm(RCGA) is proposed and a backward path tracking control algorithm is then obtained based on the linearized model. Experimental results verify the effectiveness of the proposed method.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.359-364
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• 2012

Purpose: This study was conducted to analyze the vibration absorption effect for the agricultural product transportation-trailer equipped with vibration absorbable connecting hitch, leaf spring suspension, and shock absorber simultaneously (HLS), comparing with the trailer equipped with vibration absorbable connecting hitch only(H), trailer equipped with connecting hitch and leaf spring suspension (HL), and existing trailer with no vibration absorption device (E). Methods: Vertical accelerations were measured at driver seat and front, middle, rear parts of trailer bottom with no load for 4 types of transportation-trailer, and analyzed using FFT analyzer. Results: The magnitude of average vibration accelerations occurred up to 20 Hz, at this low frequencies the severe damage for agricultural products could be represented, was lower (maximum 6 times) for HLS trailer compared with H trailer. And vibration absorption effect for HLS trailer was also higher up to 40-80 Hz and 80-100 Hz, but the difference was less. At driver seat, the vibration absorption effect was high severely for HL and HLS trailer, and the magnitude of vibration acceleration was showed less difference in comparing at trailer bottom. Conclusions: From the test results, it could be recommended that the agricultural products transportation trailer should be equipped with vibration absorption device of HLS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.638-645
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• 2014

This paper presents results of a study for development and application of container massive transportation system. The system is aimed to improve competing power of Korean container ports. This paper selects Double stack Multi-Trailer System (DMTS) under consideration of pros-con analysis between three systems alternatives as well as operation process of existing Korean container terminal companies. An analysis of turning radius is undertaken for applying the system. Key elementary technologies was derived by patent analysis. DMTS has no problems in utilization to existing Korean container ports. Further, the system is expected to highly potential to improve operational efficiency in the container ports thanks to its high unit transportation capacity.

• Journal of Advanced Navigation Technology
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• v.12 no.3
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• pp.215-219
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• 2008

Recently, a container shipping volume has increased dramatically and continued on a trend of rapid growth, and so the number of container handled at the port increase. therefore, it's increasing about concern of harbor automatism to save distribution costs in harbor. harbor automatism classifies into four large automatism's, gate automatism by using RFID that trailer come with burdening the container to be loaded on ships go though with RFID and Quay-Side container crane automatism that treats cargos loading on ships and automatism of CG that loads containers from yard, and automatism of container transporters that carries containers in between gates. To increase the using efficiency of harbor, detecting exact location of yard crane is very important matter. In this paper, propose about yard crane automatism applied UWB Location system and the development direction.

• Journal of Biosystems Engineering
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• v.28 no.2
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• pp.89-96
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• 2003

This study was aimed to identify how the main body vibration of power tiller will be transmitted to the trailer, and to find out the basic information for demage reducing method of agricultural products during transportation. The vertical vibration acceleration level was measured at 6 positions, i.e. engine, hitch, seal and three parts of trailer (front middle, and rear) for the not driving but at the engine speeds of 1,000rpm and driving at 0.35m/s. The results of this research could be summarized as follows; 1. For not driving, the accumulated acceleration level up to 120Hz was 50% of total accelerations at engine part and those were 28~41% at other parts. Those up to 40Hz were 20~30% at engine and hitch part and 2~8% at trailer part. And those up to 20Hz were 13~20% at engine and hitch part and 1~4% at trailer part 2. For the driving with 0.35m/s at paved road, the average vertical accelerations were in the range of 0.005~0.058m/s$^2$. The lowest value of 0.005m/s$^2$ was showed at engine part and the value of 0.031-0.058m/s$^2$ was showed at trailer part. 3. For the driving with 0.35m/s, the accumulated value of average vertical accelerations showed the lowest value at engine parts md showed 5 times value of engine part at trailer part especially highest value at middle part of trailer. 4. For the driving with 0.35m/s, the accumulated acceleration level up to 120Hz was 75% of total accelerations at engine part and those were 20~42% at other parts. Ant those up to 20Hz and 40Hz were 24~26% at engine part and 0.1~0.6% at trailer part.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.907-910
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• 2007

Recently, a container shipping volume has increased dramatically and continued on a trend of rapid growth, and so the number of container handled at the port increase. therefore, it's increasing about concern of harbor automatism to save distribution costs in harbor. harbor automatism classifies into four large automatism's, gate automatism by using RFID that trailer come with burdening the container to be loaded on ships go though with RFID and Quay-Side container crane automatism that treats cargos loading on ships and automatism of CG that loads containers from yard, and automatism of container transporters that carries containers in between gates. To increase the using efficiency of harbor, detecting exact location of yard crane is very important matter. In this paper, it intends to discuss about yard crane automatism applied UWB Ranging system and bring up the development direction.

• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.147-154
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• 2005

The improved hitch device, which connecting the trailer to power tiller, was developed. This device, composed with spring and rubber, could reduce the vibration and shock levels during driven on off-road. The vertical vibration accelerations for the improved hitch device were measured at 6 positions, i.e. engine, hitch, seat, and three points in trailer (front, middle, and rear) for not driving but at low engine speed of 500 rpm, and compared with the existing hitch device. The results of this study could be summarized as follows; The average vibration acceleration up to 120 Hz was $0.4m/s^2$ at engine part, but it was 0.08 and $0.05m/s^2$ at trailer for existing and improved hitch device, respectively. About $38\%$ of average acceleration level could be absorbed for the improved hitch device compared with existing hitch device. The average vibration acceleration up to 40 Hz was reduced to 0.12 and $0.06m/s^2$ at trailer for existing and improved hitch device respectively, showing the reduction effect of $50\%$. The maximum acceleration occurred at up to 20 Hz of low frequency was much higher than total acceleration occurred at up to 120 Hz, which means that much loss or damage could be occurred during transporting of agricultural products on off-road. The portions of average acceleration occurred at up to 20 Hz of low frequency were $27\%\;and\;21\%$ for the existing and improved hitch device, respectively.