• Title, Summary, Keyword: Transport

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

  • Kang, Kyung-Woo
    • Proceedings of the KOR-KST Conference
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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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Development of the Discrete-Ordinates, Nodal Transport Methods Using the Simplified Even-Parity Neutron Transport Equation

  • Noh, Taewan
    • Nuclear Engineering and Technology
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    • v.32 no.6
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    • pp.605-617
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    • 2000
  • Nodal transport methods are studied for the solution of two dimensional discrete-ordinates, simplified even-parity transport equation(SEP) which is known to be an approximation to the true transport equation. The polynomial expansion nodal method(PEN) and the analytic function expansion nodal method(AFEN)which have been developed for the diffusion theory are used for the solution of the discrete-ordinates form of SEP equation. Our study shows that while the PEN method in diffusion theory can directly be converted without complication, the AFEN method requires a theoretical modification due to the nonhomogeneous property of the transport equation. The numerical results show that the proposed two methods work well with the SEP transport equation with higher accuracies compared with the conventional finite difference method.

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Transport of a capsule immersed in a vertical pipe (수직한 수송관 내부의 캡슐 이송)

  • Kim, Taehong;Park, Ryeol;Jeong, Joonho;Kim, Wonjung
    • Journal of the Korean Society of Visualization
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    • v.17 no.1
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    • pp.19-25
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    • 2019
  • We report a study on the dynamics of the transport of a capsule immersed in a vertical pipe. Techniques to convey objects through liquid flow pipes using a hydraulic mean are used to transport sludge and hazardous materials. For the better understanding of the techniques, we developed a theoretical model to predict the transport speed of a cylindrical capsule in a vertical pipe. The comparison of the model prediction with the experiments shows that our model using the lubrication approximation precisely describes the experimental observations in cases where the gap between the capsule and pipe wall is sufficiently small. Our study suggests parameters to control the falling speed and thus enable an accurate control of the capsule speed in hydraulic transport systems.

Levels of the Proline and Glycine Betaine Transport Systems of Staphylococcus aureus at High Osmolarity (고농도 삼투환경에서 생성되는 포도상구균의 Proline과 Glycine Betaine Transport System의 수준변화에 관한 연구)

  • 배지현
    • Journal of the East Asian Society of Dietary Life
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    • v.5 no.2
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    • pp.19-26
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    • 1995
  • Staphylococcus aureus, the most salt-tolerant nonhalophilic bacterium, is the only foodborne pathogen that is able to grow at a levels below 0.90. The fundamental osmorgulatory strategy used by this organism involves the accumulation of intracellular compatible solutes such as proline or glycine betaine which are accumulated by transport and act as osmoregulators in cells. In this study, levels of proline transport systems and glycine betaine transport system of S. aureus were examined when cells are grown at high osmolarity. The levels of all three transport systems within S. aureus were elevated at high osmolarity and the most dramatic increase was found for the low-affinity proline transport system. However, in 5mM glycine betaine-supplemented medium, the level of the low-affinity proline transport system did not become elevated when cultures were grown at high osmolarity. The metabolic fate of the accumulated proline and glycine getaine was investigated by thin-layer chromatography an found to be not metabolized by S. aureus.

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Water Transport during the Single-pass Perfusion Experiments : Effects of Some Perfusates and Their Osmolality (일회통과 관류실험시 물의 수송 : 관류액의 종류와 삼투압의 영향)

  • 이정화;이현주;용철순;오두만
    • YAKHAK HOEJI
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    • v.39 no.4
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    • pp.411-416
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    • 1995
  • The single-pass perfusion experiments were performed in anesthetized rats to investigate the effects of perfusates and their osmolality on the water transport and to determine the correlation between the extent of water transport and the volume change of perfusate. Phenol red was used as a nonabsorbable marker. In normal rats, when perfused at a flow rate of 0.5 ml/min, 2-(N-rnorpholino) ethanesulfonic acid (MES) and S$\phi$rensen's phosphate buffers showed minimal net water transport as 0.125 and 0.173 %/cm of intestinal length, respectively. Hypotonic perfusate of 200 mOsm/kg of water and hypertonic perfusate of 400 mOsm/kg of water generated significant water transport compared with isotonic perfusate of 300 mOsm/kg of water. There was a linear correlation between the extent of water transport and the volume change of perfusate, suggesting that the volume change can be used as a measure of water transport.

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A Study on the Transportation Characteristics according to Beam Shape of Optical Lens Transport System using Ultrasonic Wave (초음파를 이용한 광소자 이송시스템의 빔형상에 따른 이송특성에 관한 연구)

  • Jeong, Sang-Hwa;Choi, Suk-Bong;Cha, Kyoung-Rae;Song, Suk;Kim, Gwang-Ho
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.15 no.6
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    • pp.8-14
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    • 2006
  • The object transport system is used in many industry field such as the conveyor belt, which transports huge goods in container harbor, the magnetic levitation system, and the indexing system which transports precision components such as semiconductor and optical components. In conventional transport system, the magnetic field may damage semiconductor and the contact force may scratch on the optical lens. So ultrasonic wave transport system has been proposed to replace the previous transport system. In this paper, the good transport condition of optical lens is obtained according to the flexural beam shapes. The working frequency and transport speed are measured and the vibration characteristics of the flexural beams are investigated by Laser Scanning Vibrometer.

A Study on the Some Points for Practical Attention of Transport Documents in the UCP 600 (UCP 600 운송서류 규정의 실무상의 유의점에 관한 연구)

  • Park, Suk-Jae
    • The Korean Research Institute of International Commerce and Law
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    • v.43
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    • pp.101-115
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    • 2009
  • More than two years have passed since the latest UCP, Uniform Customs and Practice for Documentary Credits, 2007 Revision, ICC Publication No.600 became valid on July 1, 2007. There has been a lot of confusions in connection with the interpretation of the new UCP since July 1, 2007. Especially the transport document articles of the new UCP are the most confusing ones. Therefore, this work intends to study some points for practical attention of transport documents in the UCP 600. Transport documents can be divided into two kinds of documents such as marine transport documents and other transport documents. But most sellers and buyers distinguish two kinds of transport documents : the document of title and the document of non-title. Most traders consider the document of title importantly and ignore the document of non-title.

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Development of Blue Organic Light-Emitting Diodes(OLEDs) Due to Change in Mixed Ratio of HTL:EML(DPVBi:NPB) Layers (HTL:EML(DPVBi:NPB) 층의 조성비 변화에 따른 청색 유기 발광 소자 개발)

  • Lee, Tae-Sung;Lee, Byoung-Wook;Hong, Chin-Soo;Kim, Chang-Kyo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.31-32
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    • 2008
  • The structure of OLEDs with conventional heterostructure consists of anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode. NPB used as a hole transport layer and DPVBi used as a blue light emitting layer were graded-mixed at selected ratio. Interface at heterojunction between the hole transport layer and the elecrtron transport layer restricts device's stability. Mixing of the hole transport layerand the emitting layer removes abrupt interface between the hole transport. layer and the electron transport layer. The stability of OLED with graded mixed-layer developed in this study was improved.

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Hydrogen Peroxide Mediates Brazilin-induced Glucose Transport in Adipocytes

  • Khil, Lee-Yong;Moon, Chang-Kiu
    • Biomolecules & Therapeutics
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    • v.12 no.4
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    • pp.228-234
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    • 2004
  • Brazilin shows hypoglycemic effect in diabetic animals through enhancement of glucose metabolisms in insulin responsive tissues. One of the major mechanisms of brazilin to enhance glucose metabolism is stimulation of glucose transport in adipocytes. In this study, the essential molecular moiety of brazilin for the stimulation of glucose transport was investigated. We found that brazilin undergoes a structural change in physiological buffer and produces hydrogen peroxide. Methylation of hydroxyl group of brazilin or addition of catalase along with brazilin resulted in the complete inhibition of brazilin-induced glucose transport in adipocytes. Because hydrogen peroxide increases glucose transport by inhibition of phosphatases, we examined the effect of brazilin on phosphatase activity. Brazilin inhibited phosphatases in a wide range of activity, and protein phosphatase 1 and 2A were also inhibited. These results suggest that the production of hydrogen peroxide by oxidation of catechol hydroxyl group of brazilin mediates glucose transport through inhibition of phosphatases which otherwise decrease glucose transport in adipocytes.

The Practical Strength of Logistics Competition Power for Efficiency of Combined Transport Transaction (복합운송의 물류경쟁력 강화를 위한 실천적 방안)

  • Lee, Hak-Seung
    • International Commerce and Information Review
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    • v.9 no.2
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    • pp.285-303
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    • 2007
  • As the interest about smooth logistics increases lately, the importance of multimodal transport, which performs the key role of logistics emerges, Through there are many issues respecting multimodal transport, the issue of the efficiency of multimodal transport seems to be the most importance. This paper examine as to the problems & systems of the multimodal transport including transportation document and customs clearance for door to door services. I wish our country will use total logistics automation systems for encouraging multimodal transport chance and make a partial amendment of commercial code including the customs clearance regulation. This study will assist in the development of logistic and the enlargement of multimodal transport transaction.

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