• Title/Summary/Keyword: Transport effect

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지하 하수터널 주변의 오염물 거동해석

  • 정일문;한일영;차성수
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.09a
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    • pp.327-330
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    • 2002
  • In this study, analyses of contaminant transport are peformed to evaluate the diffusion effect of A sewage tunnel. First, Crank's analytical method is used to measure the concentration change of contaminant with time and space. Two dimensional numerical analysis is performed to measure concentration distribution of contaminant. Both methods show that the diffusion effect is little even after 500 years. This means that when flow converges into the tunnel, the environmental effect of contaminant in tunnel is not serious because there is no advection occurs.

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The Effect of Airgap Unbalance on the LIM Performance for Light Rail Road (공극 불균형이 경전철용 LIM의 특성에 미치는 영향)

  • Jung, In-Sung;Lee, Ju;Jung, Rak-Gyo;Lee, Jong-Woo
    • Proceedings of the KSR Conference
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    • 1998.11a
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    • pp.129-136
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    • 1998
  • The LIM can be used as a transport system with wheel structure. The structural tolerance cause the airgap unbalance and that effects on the LIM performance. The effect of airgap unbalance on the motor performance such as thrust force, velocity and armature current are investigated by using Finite Element Analysis (FEA). From this numerical works, it is known that the airgap unbalance almost does not effect on the motor performance and LIM for transport system is robust to the structural tolerance.

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Effects of transport stress on physiological responses and milk production in lactating dairy cows

  • Hong, Heeok;Lee, Eunchae;Lee, In Hyung;Lee, Sang-Rak
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.3
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    • pp.442-451
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    • 2019
  • Objective: This study was conducted to investigate the effect of transport stress on physiological and hematological responses and milk performance in lactating dairy cows. Methods: Ten lactating dairy cows were randomly divided into 2 groups. The treatment group (TG) was transported 200 km for 4 h by truck, and the control group (NTG) was restrained by stanchion for 4 h in Konkuk University farm. Blood and milk samples were collected at 24 h pre-transport; 1, 2, and 4 h during transport; and 2, 24, and 48 h post-transport. Milk yields were measured at 24 h pre-transport, 0 h during transport, and 24, 48, and 72 h post-transport. Results: Leukocyte, neutrophil, and monocyte numbers in the TG were significantly higher than those of the NTG at each experimental time point. Lymphocyte numbers in the TG were significantly (p<0.05) higher than those of the NTG at 48 h post-transport. Additionally, the neutrophil:lymphocyte ratio of the TG was 45% and 46% higher than that of the NTG at 4 h during transport and 2 h post-transport, respectively. There were no significant differences in erythrocyte numbers, hemoglobin concentrations, platelet numbers, and hematocrit percentages between two groups. Cortisol levels in the TG were significantly (p<0.05) higher than those in the NTG. Milk yields in the TG were lower than those in the NTG. The somatic cell count (SCC) of the TG was significantly (p<0.05) higher than that of the NTG at 1 and 2 h during transport; that of the TG increased dramatically at 1 h during transport and gradually decreased subsequently. Conclusion: Transport stress increased blood parameters including leucocyte, neutrophil, and monocyte numbers by increased cortisol levels, but did not affect erythrocytes, hemoglobin and hematocrit levels. Additionally, transport resulted in a decrease in milk yield and reduced milk quality owing to an increase in milk SCC.

Ocular transport of hydrophilic drugs: Enhancement of the paracellular penetration across cornea and conjunctiva in the rabbit (수용성약물의 안점막 투과기전에 관한 연구: 토끼의 각막 및 결막 세포간극경로의 투과촉진)

  • Chung, Youn-Bok;Lyoo, Seen-Suk;Han, Kun
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.43-53
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    • 1996
  • The objective of this study was to determine whether 4-phenylazobezyloxycarbonyl-Pro-Leu-Gly-Pro-D-Arg (Pz-peptide), an enhancer of hydrophilic solute permeability in the intestine, could elevate the paracellular permeability of hydrophilic drugs across cornea and conjunctiva in the rabbit. The in-vitro penetration of hydrophilic drugs (mannitol, atenolol) and lipophilic drug (propranolol) across the rabbit cornea and conjunctiva was studied either in the presence or absence of 3 mM Pz-peptide. Drug penetration was evaluated using the modified Ussing chamber. The conjunctiva was more permeable than the cornea to all drugs. Pz-peptide showed enhanced effects on the drug transport across cornea and conjunctiva in a concentration dependent manner. Effects or ion transport inhibitor on the mannitol penetration were then investigated. Mannitol penetration was not changed by serosal addition of $100\;{\mu}M$ ouabain, suggesting that $Na^+/K^+$ ion tranporter was not involved in the Pz-peptide induced elevation of paracellular drug permeability. Furthermore, effects of Pz-peptide and EDTA on the transport of atenolol and propranolol into the ocular tissues or blood circulation after its administration into both eyes were investigated. EDTA showed enhanced effect on propranolol transport into the ocular tissues, but Pz-peptide did not show significant difference. Systemic absorption of propranolol by the addition of EDTA or Pz-peptide was not changed. On the other hand, EDTA and Pz-peptide elavated the atenolol transport into the ocular tissues. The transport of atenolol into the blood circulation was also enhanced by the addition of EDTA, but no effect was observed by the addition of Pz-peptide. The above findings suggest that Pz-peptide would be used as an paracellular pathway enahncer of hydrophilic drugs into the eye, without affecting the systemic absortion of topically applied opthalmic drugs.

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Numerical Upwelling Experiment for Optimum Arrangement of Artificial Seamount (용승을 고려한 인공해중산 최적배치 수치실험)

  • Kim, Seong-Hyeon;Kim, Dong-Sun
    • Journal of Environmental Science International
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    • v.20 no.8
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    • pp.997-1009
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    • 2011
  • In order to estimate volume transport by upwelling for single artificial seamount, same shape and size of artificial seamount already deployed was applied to numerical experiment. The result showed that strong upwelling appeared at front while took place downwelling at rear. The strongest upwelling existed at the top of the artificial seamount. Volume transport by upwelling was computed as 785 m3/s. Column arrangement was applied to two artificial seamount in three cases; case 1) no clearance, case 2) sixty-five meters of clearance as half of artificial seamount's length, and case 3) hundred-thirty meters of clearance as an artificial seamount's length. All cases of column arrangements showed more upwelling volume transport than that of single seamount. Particularly, the case of no clearance calculated as 106% and appeared the most upwelling effect comparing to two other cases. Row arrangement was also applied to two artificial seamount in three cases; case 4) no clearance, case 5) forty meters of clearance as an artificial seamount's width, and case 6) eighty meters of clearance as twice of artificial seamount's width. Upwelling volume transport in case 4 increased 48% than the case of single seamount. Other two cases of 5 and 6 were estimated as 97% increased and more effective than case 4. According to the case experiments, column arrangements show more upwelling volume transport than that of row arrangements. In cases of column arrangements, with decreasing clearance between two seamount, the effect increases while showing maximum value at clearance zero. In cases of row arrangements, on the contrary, with decreasing clearance between two seamount, the effect decreases while showing minimum value at clearance zero. Since simple barotropic condition was considered for this study, further study is necessary by considering baroclinic condition to get close to reality. In conclusion, in deploying artificial seamount, optimal arrangement should be well designed to enhance primary and secondary productivity and to increase the diversity of species as well as reducing time and space.

A Study on The Revision of UCP600 concerning the Sea Transport Documents (UCP 600 해상운송서류(海上運送書類) 규정(規定)의 주요(主要) 개정사항(改正事項)에 관한 연구(硏究))

  • Park, Sae-Woon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.35
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    • pp.71-98
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    • 2007
  • UCP 600 approved at the Banking Commission Meeting of ICC at the end of October, 2006 comes into effect from July 1, 2007. The main revision of the UCP 600 concerning the sea transport document are as follows. First, if the bill of lading contains an on-board-notation, with the date of shipment, the date stated in the on-board-notation will be deemed the date of shipment. Secondly, phrases "on its face" and "otherwise authenticated" should be eliminated. Thirdly, when an agent signs for or signs on behalf of the master, there is no longer a need for the name of master to be quoted. Fourthly, the terminology "loading on-board or shipped on a named vessel" is changed to "shipped on-board a named vessel." Fifthly, phrases "the rejection of the documents transported only by sail" is removed. Finally, new rule in UCP is the signing of a charter party bill of lading by the charterer or a named agent on behalf of the charterer. My assessment of the revision in UCP 600 is as follows: Because a freight forwarder transport document is a weaker form than a liner bill of lading as collateral, banks may need a secure measure as to protect themselves from such a weak collateral effect. we recognize that Such a weak collateral effect stemmed from the elimination of rules in UCP 500 article 30, and the admission of transport documents issued by the freight forwarder as long as any one besides carrier, shipper, and charterer satisfies the requirements of transport document clauses in UCP 600. Finally, I hope the Commentary on UCP 600 will serve to explain the ambiguities remaining in the new rules.

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Transport Spillover Effect on Airport Networks and Its Impact on Regional Economy (운송 파급효과가 항공네트워크와 지역경제에 미치는 영향)

  • Xinchen Wang;Po-Lin Lai
    • Korea Trade Review
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    • v.47 no.4
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    • pp.35-52
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    • 2022
  • Air transport is at the core of global economic growth. There is a close relationship between the flow of regional elements and the growth of the regional economy. It is easy to misestimate the impact of airports on the regional economy without considering spatial spillover effects. This study attempted to establish an asymmetric economic geographical weight matrix by applying the Spatial Durbin Model with cargo volume and passenger numbers as indicators. The influence of spillover effects on the regional economy, including direct spillover effects and indirect spillover effects are studied. The results revealed that passenger numbers and cargo volume have significant positive spillover effects on the regional economy. The driving effect of the airport on the regional economy was considered from a wider space scope. This study contributes to the scientific evaluation of the aviation economy.

A Study on the Ripple Effect of Physical Distribution Service Industry on National Economy (물류서비스 산업의 국민경제적 파급효과 분석)

  • Jeong, Boon-Do;Hong, Geum-Woo
    • Journal of Korea Port Economic Association
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    • v.24 no.2
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    • pp.193-208
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    • 2008
  • This study aims to analyse the ripple effect of Physical distribution service industry on national economy using input-output tables and present the results as data for political plans in this field. For the analysis, it uses input-output tables developed and published by Sank of Korea in 1998, 2000, and 2003. To sum up the results, production inducement effects are 1757 for railroad transport, 1688 for road transport and 1617 for loading. Import inducement effects of assistant services, loading, storage, warehouse and other transport-related services are low while the effects of water and air transport are high as follows: 0.679 and 0.558 respectively. Then, added-value inducement effects are presented as follows: 0.841 for railway transport, 0.828 for road transport, 0.962 for transport assistant service, 0.939 for loading, 0.938 for storage and warehouse, and 0.942 for other transport-related services. Sensitivity dispersion index of road transport is high while that of water transport, storage and warehouse is low. And influence coefficient of railway and road transport is high while that of water and air transport is low. In respect to the employment structure of Physical distribution service industry, 744,000 are employed for road transport industry, which is the largest number, 19,000 for air transport and 20,000 for assistant services, which is the least number.

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Effect of Nonuniform Vertical Grid on the Accuracy of Two-Dimensional Transport Model

  • Lee, Chung-Hui;Cheong, Hyeong-Bin;Kim, Hyun-Ju;Kang, Hyun-Gyu
    • Journal of the Korean earth science society
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    • v.39 no.4
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    • pp.317-326
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    • 2018
  • Effect of the nonuniform grid on the two-dimensional transport equation was investigated in terms of theoretical analysis and finite difference method (FDM). The nonuniform grid having a typical structure of the numerical weather forecast model was incorporated in the vertical direction, while the uniform grid was used in the zonal direction. The staggered and non-staggered grid were placed in the vertical and zonal direction, respectively. Time stepping was performed with the third-order Runge Kutta scheme. An error analysis of the spatial discretization on the nonuniform grid was carried out, which indicated that the combined effect of the nonuniform grid and advection velocity produced either numerical diffusion or numerical adverse-diffusion. An analytic function is used for the quantitative evaluation of the errors associated with the discretized transport equation. Numerical experiments with the non-uniformity of vertical grid were found to support the analysis.