• 제목/요약/키워드: Transport System

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초정밀 자기부상 물류 이송장치의 제어 및 공극 센서 오프셋 추정 연구 (A Study on the Control and Estimation of Gap Sensor Offset in High-Precision Magnetic Levitation Transport System)

  • 김민;김창현;하창완;원문철
    • 전기학회논문지
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    • 제67권1호
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    • pp.87-95
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    • 2018
  • The high-precision magnetic levitation transport system is a transport device applying the principle of magnetic levitation. So it is preferable for manufactory process of semiconductor and display industries. In this system, the gap sensors are arranged discontinuously and turned on or off when the tray moves in the running direction. Therefore, precise gap data is important for precise control of the carrier. However, a slight error occurs in the process of installing the gap sensor. So, in this paper, we introduce the high-precision magnetic levitation transport system for OLED evaporation process. Also, we propose a strategy for stable flight control and an offset algorithm for tracking installation errors transport system. The performances of the proposed algorithm are validated through simulation.

A Study of the Number of Distribution Channel Levels for the Road Transportation Systems

  • Kang, Kyung-Woo
    • 대한교통학회:학술대회논문집
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    • 대한교통학회 1998년도 Proceedings The 4th International Transport Symposium
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    • pp.91-99
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    • 1998
  • Generally, the tons lifted and ton-kilometers are widely used to analyze the road freight transport. However, these two indicators are simply to show the road freight transport statistics rather than to explain the road freight transportation systems. In this study, the variables such as the number of distribution channel levels, the integral distance, tons in transport and the average transport distance are defined and estimated to investigate the road freight transport system of Korea. In order to compare the road transport system of Korea to other countries, the comparative study was conducted including USA, Japan, Holland and Taiwan. The major findings of this study are as follows; i) The number of distribution channel levels and integral distance of Korea and Taiwan have been increased, but the average transport distance decreased from 1971 to 1996 period. ii) On the contrary to Korea case, the number of distribution channel levels and integral distance of US, Japan and Holland have been decreased, but the average transport distance increased. iii) In the time-series model analysis shows that the number of distribution channel levels are statistically positively closely related to the logistics costs and the costs of transportation as a percentage of GDP.

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복합운송인(複合運送人)의 책임(責任) 한계(限界)에 대한 형태별(形態別) 분류(分類)와 실무상(實務上) 적용(適用) (A Pattern of Multimodal Transport Liability and its Adaptation on Practice)

  • 김중관
    • 무역상무연구
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    • 제13권
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    • pp.257-281
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    • 2000
  • The world economy is becoming increasingly globalized. The globalization has resulted in far reaching agreements to deepen trade liberalization and enlarge its scope to cover new areas in addition to strengthening its supporting institutional base. Economic growth has developed international trade which has accelerated the development of international carriage of goods in 21st century. The international trade is basically founded on the contract of international sale of goods and backed up by the contract of international carriage of goods and the insurance on the goods carried. It is essential to incorporate each other sections for the efficient development of international trade. As a result of rapid expansion of international carriage of goods, rationalization of transport was required, which has brought about the International Multimodal Transport System through containerization. The approach to liability system will be a right way to solve the insurance problems for the development and enlargement of world trade volume. International multimodal transport system has affected international trade a lot, especially the field of insurance a grate deal. This paper is to analyze contents of liability system on Multimodal Transport with in the UN Convention on International Multimodal Transport of goods.

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Studies on the Macrocycle mediated Transport in a Bulk Liquid Membrane System of Transition Metal Ions

  • Cho, Moon-Hwan;Seon-Woo, Kie-Hwa;Heo, Moon-Young;Lee, In-Chong;Yoon, Chang-Ju;Kim, Si-Joong
    • Bulletin of the Korean Chemical Society
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    • 제9권5호
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    • pp.292-295
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    • 1988
  • Macrocyclic ligands have been studies as cation carriers in a bulk liquid membrane system. $Cu^{2+}$ has been transported using nitrogen substituted macrocycles as carriers and several transition metal ions($M^{n+}\;=\;Mn^{2+},\;Co^{2+},\;Ni^{2+},\;Cd^{2+},\;Pb^{2+}\;and\;Ag^{+}$) have been transported using $DBN_3O_2,\;DBN_2O_2,\;Me_6N_414C4$ and DA18C6 as carriers in a bulk liquid membrane system. Competitive $Cu^{2+}-M2^+$ transport studies have also been carried out for the same system. In single cation transport experiments, the best macrocyclic ligand for transport is a ligand that gives a moderately stable rather than very stable complex in the extraction. However, when both cations are present in the source phase, the cation which forms the most stable complex with carrier is favored in transport over other cations. Generally, the nitrogen substiituted macrocycles transport $Cu^{2+}$ selectively over $Mn^+$. Ligand structure, equilibrium constant (or stability constant) for complex formation, source phase pH and carrier concentration are also important parameters in transport experiments.

Sensitivity Changes of Auxin Transport System in Maize Coleoptile Segments

  • 윤인선
    • Journal of Plant Biology
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    • 제36권1호
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    • pp.59-66
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    • 1993
  • In maize coleoptile segments where auxin transport capacity decreases with time following excision, susceptability of the tissue to transport inhibitors such as N-1-naphthylphthalamic acid (NPA), 3,4,5-triiodobenzoic acid (TIBA) or high concentrations of IAA was found to be rather increased. A time-dependent increase in the sensitivity to NPA can be postulated since the dose-response curve for NPA was shifted in the‘aged’tissue to the left (i.e. lower concentration). Preincubation of the tissue at a low temperature abolished the time-dependent sensitivity change, suggesting that cellular metabolism could be involved. The NPA-sensitive state was also brought about by calcium depletion of the tissue, which can be partially reversed by addition of calcium. Presence of exogenous IAA in the preincubation medium kept the auxin transport system from decay, implicating auxin as an endogenous controlling factor. Results of our experiments indicate a reversible, time-dependent changes of auxin transport system in which transport capacity and sensitivity to NPA are tightly coupled. Changes in the sensitivity to NPA were also seen in auxin action as well.

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복합운송경로 선정을 위한 평가기준에 관한 연구 (Study on Evaluation Criteria for Multimodal Transport Routing Selection)

  • 김소연;최형림;김현수;박남규;조재형;박용성;조민제
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 춘계학술대회 및 창립 30주년 심포지엄(논문집)
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    • pp.265-271
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    • 2006
  • 전 세계적으로 생산과 판매, 유통이 펼쳐져 세계경제는 글로벌화 되고 국제운송체계는 신속성과 부가가치 서비스를 중요시하는 운송체계로 변화함에 따라 국제운송체계는 해상운송, 항공운송 그리고 철도운송을 시스템적으로 연계하는 국제복합운송 중심체계로 전환되고 있다. 이러한 변화에 따라 생산과 판매, 유통이 적시에 제공되고, 글로벌 네트워크상의 소비자에게 다차원적인 물류서비스를 제공할 수 있는 국제복합운송경로가 필요하지만 국제운송을 위한 정보 연계 및 운송수단 간의 연계 시스템이 미비하여 활성화되지 못하고 있다. 특히 국내에서는 3자 물류업체, 운송업체 둥의 선정기준은 제시되고 있으나, 운송을 계획하고 수행하는 물류전문업체들이 국제복합운송경로를 선정하는데 있어 체계적인 평가기준이 제시되지 못하고 있다. 이에 본 연구에서는 복합운송경로선정에 대한 주요 문헌연구를 정리하고, 업체 담당자들의 인터뷰를 통해 복합운송경로 선정을 위한 평가기준을 도출하고, 이를 계층분석기법(AHP)을 이용하여 측정하여 복합운송경로 선정을 위한 평가기준을 제시하는데 목적이 있다.

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Evaluation of Bacterial Transport Models for Saturated Column Experiments

  • Ham, Young-Ju;Kim, Song-Bae;Kim, Min-Kyu;Park, Seong-Jik
    • 한국농공학회논문집
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    • 제48권7호
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    • pp.55-63
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    • 2006
  • Bacterial transport models were evaluated in this study to determine the suitable model at describing bacterial transport in saturated column experiments. Four models used in the evaluation were: advective-dispersive equation (ADE) + equilibrium sorption/retardation (ER) + kinetic reversible sorption (KR) (Model I), ADE + two-site sorption (Model 2), ADE + ER + kinetic irreversible sorption (KI) (Model 3), ADE + KR + KI (Model 4). Firstly, analyses were performed with the first experimental data, showing that Model 4 is appropriate for describing bacterial transport. Even if Model 1 and 2 fit well to the observed data, they have a defect of not including the irreversible sorption, which is directly related to mass loss of bacteria. Model 3 can not properly describe the tailing observed in the data. However, further analysis with the second data indicates that Model 4 can not describe retardation of bacteria, even if the sorption-related parameters are varied. Therefore, Model 4 is modified by incorporating retardation factor into the model, resulting in the improved fitting to the data. It indicates that the transport model, into which retardation, kinetic reversible sorption, and kinetic irreversible sorption are incorporated, is suitable at describing bacterial transport in saturated column experiments. It is expected that the selected transport model could be applied to properly analyze the bacterial transport in saturated porous media.

도서관광 활성화를 위한 연안-내륙 연계교통체계 구축 방향 (Suggestions for Building Coast-Inland Linkage Transport System to Promote Island Tourism)

  • 최창호
    • 한국항만경제학회지
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    • 제28권2호
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    • pp.43-59
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    • 2012
  • 자연경관이 우수한 도서지역을 찾는 관광객이 지속적으로 증가하고 있다. 또한 국민소득 수준과 여가시간의 증가로 장래 도서지역 관광객이 더욱 증가할 것으로 예상된다. 이들 관광객을 지원하는 관광교통의 측면에서 볼 때 연안여객터미널과 육상교통수단과의 연계교통 효율화는 매우 중요하지만 실상은 잘 이루어지고 있지 않다. 이는 연안여객터미널 위치가 육상교통수단의 터미널과 떨어져 있으며 이를 서로 연결해야 하는 시내버스 등 대중교통수단의 지원이 미흡하기 때문이다. 본 연구는 도서지역 관광 활성화를 위한 연계교통체계 개선 방향을 제시하였다. 주요 내용은 시내버스를 중심으로 하는 연계교통체계의 구축과 보행거리의 최소화, 도서지역 관광특성에 맞도록 여객선 운항계획의 조정, 관광객의 운임부담을 완화하기 위한 여객선의 대중교통화 방안, 교통수단간 시간적 공간적 연계 및 이를 통합교통정보로 제공하는 방안 등이다.

준설시험루프를 이용한 모래-물 혼합물 배송에 관한 연구 (Study of Hydraulic Transport of Sand-water Mixture by a Dredging Test Loop)

  • 이만수;박영호;이영남;정충기
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.1504-1511
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    • 2005
  • The efficiency of the hydraulic transport of soil-water mixtures is an important factor in designing and operating a pump & pipeline system and is directly connected with dredging cost and working period. However, the hydraulic transport mechanism in the slurry flow inside the pipeline such as frictional losses, specific energy consumption, deposition velocity has not been well established. In this study a new dredging test loop system was designed and built. It is composed of a slurry pipeline with pipes of different diameters, a centrifugal slurry pump and a diesel engine connected with the slurry pump. and equipped with modern measuring facilities that enable to measure all important characteristics of a transportation system. The objective of this paper is to discuss the efficiency of the hydraulic transport of the Jumoonjin sand-water mixtures in the dredging test loop and to present simple equations induced from the test results of the loop that can express the transport product and the transport productivity.

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복합운송인의 책임제한 방식과 한도액 (A Review on Limit of Liabilities of Multimodal Transport Operator in Korea)

  • 서지민
    • 무역상무연구
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    • 제77권
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    • pp.145-168
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    • 2018
  • The purpose of this paper is to introduce the limitation of liabilities of multimodal transport operators(MTO) in Korea. Also, this paper reviews the revised draft of Korean Commercial Code in 2015. This paper analyzes Korean multimodal transport systemand the limitation of liabilities of MTO by analyzing articles, regulations and practices of Korean Commercial Code and it's the draft in 2015. The paper, also, studies multimodal transport rules by comparing specifically international treaty, rules, or practices. In Korea, Article 816 of Commercial Code treats multimodal transportation adopting the network liability regime. The Article describes only the case of the multimodal transportation where the maritime carriage is engaged. Korea proposed the draft of multimodal transport regulation of Commercial Code in 2015 because present law could not apply for the multimodal transportation involved in the air or land carriage. This paper support the draft of Korean Commercial Code in 2015 because it is necessary to make a predictable legal system of multimodal transport and the limitation of liability reflecting practices or customs.

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