• Journal of the Korean Applied Science and Technology
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• v.18 no.1
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• pp.1-6
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• 2001

Theoretical model has been studied for the transport phenomena of molecules in the system where an electric potential is applied to the system in the axial direction. The effect of electrophoretic convection in the polymeric media is significantly contributed to separate large ionic-molecules because the conformation of large ionic-molecule quickly orients in the field direction. The dependence of the transport in the polymeric media upon field intensity and molecular size aids in understanding the transport of large ionic-molecule in the system, since the convective velocity of large ionic-molecule is accelerated inside a porous material. The transport distance of individual large ionic-molecule can be predicted using the reptation theories.

• Progress in Superconductivity and Cryogenics
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• v.8 no.3
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• pp.59-62
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• 2006

For electric power applications of Bi-2223/Ag superconducting tapes, a transport characteristic is important issue. A transport characteristic is strongly depends on the magnitude and direction of external time-varying magnetic field. To verify a effect of external magnetic field, we manufactured a prototype magnet and obtained transport characteristics with respect to the magnitude, the direction and the frequency of external magnetic field. The data acquired in this paper will be used as a source for the study of HTS electric power applications which is supposed to carry on.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.2
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• pp.81-94
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• 2007

In order to solve the traffic problem which comes to be serious at day, the impotance of Intelligent Transport Systems(ITS) that accomplish information gathering, information processing, information offering with up-to-date scientific techniques is coming to be high. But many local self-government group want to solve the traffic problems with introduction of ITS, however, it is a actual condition where the systematic effective analysis is insufficient. This study establishes the methodology of effective analysis as introduction of ITS, which refers to the inside and outside of the country instance. And then, this research accomplishes direct and indirect effective analysis with the case study. As a result of SUWON ITS introduction effect analysis, the travel speed of TRC mode is increased 31%, and the delay of TRC mode is diminished 43.9% than before introducing case. Most of the citizen felt the improvement effect of ITS system operation, and the majority wanted the expansion of the ITS system in survey. The analysis of economic result that B/C ratio is 5.12. So, The the effect and economic propriety of the ITS enterprise appeared with the fact that it is sufficient.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.2
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• pp.125-130
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• 2005

We examined the effect of leptin on the insulin resistance in skeletal muscles by measuring the glucose transport. Male Wistar rats were fed with chow or high-fat diets for 30 days. Three days before sacrifice, high-fat fed rats were subcutaneously injected with leptin (1 mg/kg body weight) for 3 days. The glucose transports in the epitrochlearis and soleus muscle were not different among the experimental groups under basal state, however these were decreased significantly in the high fat-diet rats under insulin-stimulation (p＜0.01). Leptin treatment recovered the decreased glucose transport in the epitrochlearis (p＜0.05) and soleus (p=0.08). Triglyceride concentration in the soleus muscle was increased significantly in the high fat-fed rats, compared to chow diet rats (p＜0.01), and it was decreased significantly by leptin treatment (p＜0.01). The glucose transport was measured under basal and $60{\mu}u/ml$ of insulin with or without 50 ng/ml of leptin. Leptin had no direct stimulatory effect on glucose transport under both basal and insulin-stimulated conditions in vitro. These results demonstrate that leptin injection to high fat diet fed rats recovered impaired insulin responsiveness of the skeletal muscles and muscle triglyceride concentration. However, there was no direct stimulatory effect of leptin on insulin sensitivity of the skeletal muscle in vitro.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.1
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• pp.9-14
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• 2009

We cultured canine kidney(MDCK) cells stably expressing aquaporin-2(AQP2) on collagen-coated permeable membrane filters and examined the effect of extracellular ATP on arginine vasopressin(AVP)-stimulated fluid transport and cAMP production. Exposure of cell monolayers to basolateral AVP resulted in stimulation of apical to basolateral net fluid transport driven by osmotic gradient which was formed by addition of 500 mM mannitol to basolateral bathing solution. Pre-exposure of the basolateral surface of cell monolayers to ATP(100 ${\mu}M$) for 30 min significantly inhibited the AVP-stimulated net fluid transport. In these cells, AVP-stimulated cAMP production was suppressed as well. Profile of the effects of different nucleotides suggested that the $P2Y_2$ receptor is involved in the action of ATP. ATP inhibited the effect of isoproterenol as well, but not that of forskolin to stimulate cAMP production. The inhibitory effect of ATP on AVP-stimulated fluid movement was attenuated by a protein kinase C inhibitor, calphostin C or pertussis toxin. These results suggest that prolonged activation of the P2 receptors inhibits AVP-stimulated fluid transport and cAMP responses in AQP2 transfected MDCK cells. Depressed responsiveness of the adenylyl cyclase by PKC-mediated modification of the pertussis-toxin sensitive $G_i$ protein seems to be the underlyihng mechanism.

• Journal of Acupuncture Research
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• v.18 no.4
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• pp.143-151
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• 2001

Objective : This study was undertaken to determine whether Scutellaria balicalensis Georgi (SbG) extract exerts the protective effect against oxidant-induced alterations in organic cation transport in the renal proximal tubule. Methods : Organic cation transport was estimated by examining alterations in tetraethylammon - ium(TEA) uptake in rabbit renal cortical slices. The slices were treated with 0.2 mM tBHP for 60 min at $37^{\circ}C$. tBHP caused an inhibition in TEA uptake by renal cortical slices. Such an effect was accompanied by depressed Na+-K+-ATPase activity and ATP depletion. tBHP also induced a significant increase in LDH release. Results : SbG prevented tBHP-induced inhibition of TEA uptake in a dose-dependent manner at the concentration ranges of 0.05-0.1%. tBHP-induced inhibition of Na+-K+-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. tBHP-induced LDH release also was blocked by SbG. tBHP caused a significant increase in lipid peroxidation and its effect was prevented by SbG. Conclusion : These results suggest that SbG prevents oxidant-induced alterations in organic cation transport in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.

• Water Engineering Research
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• v.3 no.2
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• pp.75-84
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• 2002

An Euler-Lagrange two-phase flow model is presented fur simulation sheet-flow transport under wave and current. The flow is computed by solving the Reynolds Averaged Navier-Stokes equation in conjunction with the k-$\varepsilon$ turbulence model for turbulence closure. The sediment transport is introduced as a motion of granular media under the action of unsteady flow from the Lagragian point of view. In other word, motion of every single particle is numerically traced with Movable Bed Simulator (MBS) code based on the Distinct Element Method (DEM), in which the frequent interparticle collision of the moving particles during the sheet-flow transport is sophisticatedly taken into account. The particle diameter effect on time-dependent developing process of sheet-flow transport is investigated, by using three different diameter sizes of sediment. The influence of an imposed current on oscillatory sheet-flow transport is also investigated. It is concluded that the sediment transport rate increases due to the relaxation process related to the time-lag between flow velocity and sediment motion.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.255-262
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• 2011

KORAIL's Rail freight tonnage approximately 39 million tons in 2010, coal transportation thereof approximately 6.2 million tons, it is about 15.7 percent in the entire railway transportation. In addition, the incomes of rail transport of coal is 51.7 billion won which is about 15.8 percent of total. It is the third largest proportion of tonnage and profit on rail freight items. However, the percentage of rail transport of coal has been decreased by the government policies to reduce the production of anthracite and to supply non-thermal power anthracite preferentially which depends on truck transport. Such reasons effect to transport incomes of stations located in Gangwon province which handle coal transport a lot. Accordingly, this study tries to explicate the fundamental problems and find solution for stations to maintain its incomes.

• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.21-26
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• 1996

In our previous studies, we reported that lead intoxicated nerve cell by inhibition of the Na$^{+}$-K$^{+}$ ATPase activity and reduction of myo-inositol in nerve cell. As the second series of experiments, in order to understand toxic mechanism of lead for nerve cell, the characteristics of myo-inositol transport system and the effect of lead on its system have been studied in the sciatic nerves of control and lead-treated rats. A lead intoxicated animal model was induced by feeding diet containing lead to Sprague-Dawley rat for two weeks. Four weeks aged Sprague-Dawley rats were divided into three group : normal control group, 10ppm-lead treated group, 100ppm-lead treated group. All rats were sacrified at the end of two weeks. The rate o myo-inositol transport by sciatic nerve isolated from lead-treated rat was significantly decreased compared with that of control rat. This deficit results from that myo-inositol transport system which is carrier mediated and sodium-potassium dependent was inhibited by the lead treatment (both 10ppm and 100ppm) due to increase of the Km value without affecting Vmax value for myo-inositol carrier. These observations suggest that the toxic mechanism of lead on nerve myo-inositol transport system might be a change of affinity without change of maximum transport velocity for carrier.

• The Journal of Pediatrics of Korean Medicine
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• v.17 no.1
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• pp.1-16
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• 2003

Background: Delayed mucociliary clearance develops the pooling of nasal secretion in the nasal cavity and is a common cause of vicious cycle of symptoms in chronic sinusitis. mucociliary clearance depends on the ciliary activity, the rheological property of the secretion and on the interaction between cilia and the mucous blanket. Objective: To demonstrate the therapeutic effect of herbal medicine (Hyunggyeyungotang) on the mucociliary transport in the chronic sinusitis using saccharine Materials and methods: Forty patients treated in our hospital between september 2000 and september 2001 were studied. Before and after therapy group are composed of twenty patients. Kamihyunggyeyungyotang was administered mainly. We analyzed the saccharine mucociliary transport time of patients. Results: 1) In the control group, the transport time is about 13.4 minutes. 2) In chronic sinusitis before Kamihyunggyeyungotang therapy, the transport time is about 27.7 minutes. 3) In chronic sinusitis after Kamihyunggyeyungotang therapy, the transport time is about 13.8 minutes. Conclusion: Delayed mucociliary transport time in chronic sinusitis is earlier after Kamihyunggyeyungotang therapy.