• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.77-86
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• 2008

Firstly, this study is to compare two types of productivity changes in Seoul's urban bus industry by public transport reforms: one with considering accident costs (ML), the other without considering accident costs (M). The directional distance function (DDF), which is a form of data envelopment analysis, and the Malmquist (Luenberger) productivity index (ML, M) are used for the analysis. The results show that productivity increased regardless of accident costs over time, and the ML index is a little higher than the M index, which means that most firms experienced more of a reduction ratio of accident costs than a reduction ratio of inputs. Secondly, this paper is to analyze how reforms affect productivity changes. The results show that operational speed improvements or passenger increases most affect productivity increases, which means that the installment of median bus lanes or introduction of free transfers among public transport modes were effective in reducing both inputs and accident costs. However, operational system reforms including mid-public management were related with productivity changes but they were not as effective.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.8 s.251
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• pp.796-805
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• 2006

In this study, the problem of using the mixing index as a measure of the mixing performance for a certain flow field has been discussed. The flow model subjected to this study is the two-dimensional unsteady lid-driven cavity flow. The transport equation for the concentration within the cavity was solved by using the finite volume method where the convective terms are discretized with the central difference scheme. It was shown that both the concentration dispersion and the mixing index depend highly on the initial distribution of the concentration, and therefore the mixing index obtained from the concentration dispersion equation loses its universal applicability.

• Korean Journal of Acupuncture
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• v.34 no.1
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• pp.56-69
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• 2017

Objectives : The purpose of this study is to compare the effects of laser acupuncture to the 532 nm on the five transport points with the heart meridian for treatment to hypertensive disease in rats with L-NAME induced hypertensive. Methods : Hypertensive was induced by L-NAME for 3 weeks. The laser acupuncture therapy on the five transport points of heart meridian(Laser Well Point-HT9, Laser Brook Point-HT8. Laser Stream Point-HT7, Laser River Point-HT4 and Laser Sea Point-HT3) was treated twice a week for 5 times. The hypertensive was measured using a cardiac hypertrophy, atherogenic index, TG/HDL-cholesterol ratio, TCHO, HDLC, TG, AST, ALT, antioxidative effectiveness and glutathione peroxidase quality of hypertensive rats induced by L-NAME. Results : Blood pressure were decreased significantly after the laser acupuncture of Well, Brook and Sea Point groups. Cardiac hypertrophy were decreased at the laser acupuncture of Brook and Stream Point groups. Athrogenic index was decreased at the laser acupuncture of Well, Stream, River and Sea Point groups. TG/HDL-cholesterol ratio was decreased at the laser acupuncture of all groups. Total cholesterol was decreased significantly at the laser acupuncture of Well Point group. High density lipoprotein cholesterol and total cholesterol were decreased significantly at the laser acupuncture of Well, Stream and River Point groups. Triglyceride was decreased significantly at the laser acupuncture of Stream Point group. Cu/Zn-Superoxide Dismutase (Cu/Zn-SOD) and glutathione peroxidase(GPX) were increased significantly at the laser acupuncture of Well Point group. Conclusions : The laser acupuncture treatment in five transport points of the Heart Meridian was effective for lowering blood pressure, cardiac hypertrophy, Atherogenic index and HTR, and for enhancing antioxidant activity.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.179-183
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• 2008

In the present study, we examined the effects of several therapeutics of Alzheimer's disease, such as donepezil hydrochloride, tacrine and $\alpha$-phenyl-n-tert-butyl nitrone (PBN) on choline efflux from brain to circulating blood. The brain-to-blood efflux of [$^3H$]choline in rats was significantly inhibited by tacrine and PBN. Also the [$^3H$]choline efflux was reduced by tacrine and donepezil hydrochloride in the TR-BBB cells, in vitro the blood-brain barrier (BBB) model. These results suggest that these drugs may influence choline efflux transport from brain to blood and regulate the choline level in brain resulting in the increase of acetylcholine synthesis.

• Biomolecules & Therapeutics
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• v.14 no.1
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• pp.45-49
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• 2006

The purpose of this study was to clarify the efflux transport system of choline from brain to blood across the blood-brain barrier (BBB) in rats using the brain efflux index (BEI) method. $[^3H]$Choline was micro-injected into parietal cortex area 2 (Par2) of the rat brain, and was eliminated from the brain with elimination halflife of 45 min. The BBB efflux clearance of $[^3H]$choline was about 124 mL/min/g brain, which was determined from combination of an elimination rate constant $(1.54X10^{-2}min^{-1})$ and the distribution volume in the brain (8.05 mL/g brain). The efflux of $[^3H]$choline was inhibited by unlabeled choline in a dose-dependent manner and was significantly inhibited by cationic substrates, such as hemicholinium-3 and tetraethylammonium (TEA). These results suggest that the BBB may act as an efflux pump for choline to reduce the excessive choline concentration in the brain interstitial fluid.

• Journal of Industrial Convergence
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• v.20 no.12
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• pp.87-96
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• 2022

The Ministry of Land, Infrastructure and Transport has also been promoting the commercialization of land transport technology to commercialize the technologies owned by small and medium-sized venture companies, and to support the transfer and commercialization of public technologies. At this point, in order to improve the investment effect of subsequent new projects and to select excellent research institutes, it is necessary to establish a valid evaluation index system suitable for the purpose of the project. The evaluation index system for subsequent new projects should be linked to the project objectives and goals of the preceding project, and should be selected in consideration of existing evaluation indicators to prevent interruption of research results. Therefore, this thesis sets the evaluation index system into multiple scenarios through hierarchical cluster analysis using the evaluation result data for each evaluation committee for small and medium venture companies participating in the land transportation technology commercialization support project, and then analyzes the structural equation model. As a result of scenario analysis, considering the measurement effect of each path representing the causal relationship between evaluation indicators and the effect of each evaluation index on evaluation items, the scenario with the highest impact on the evaluation result was selected as an improvement plan.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.320-325
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• 2003

Acoustic-Pressure Response of diluted hydrogen-air diffusion flames is investigated numerically by adopting a fully unsteady analysis of flame structures. In the low-pressure regime, the amplification index remains low and constant at low frequencies. As acoustic frequency increases, finite-rate chemistry is enhanced through a nonlinear accumulation of heat release rate, leading to a high amplification index. Finally, the flame responses decrease at high frequency due to the response lag of the transport zone. For a medium-pressure operation and low-frequency excitation, the amplification index is low and constant. It then decreases at moderate frequencies. As frequency increases further, the amplification index increases appreciably due to an intense accumulation effect.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.3
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• pp.237-245
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• 2020

In this paper, I introduce Phase-Change Cooling for thermal management of high power devices that can be applied to High Power Laser and Electric Propulsion Systems which are composed of multiple distributed superheat sources. Phase-Change Cooling can be good used to efficient cooling of their heat sources. Phase-Change Cooling has extremely high efficiency of two-phase heat transport by utilizing heat of vaporization, relatively low flow rates and reduced pumps power. And I suggest TPI(Thermal Performance Index) which is a quantitative performance index of Phase-Change Cooling for thermal management. I quantify the performance of Phase-Change Cooling by introducing TPI. I present the test results of TPI's changing refrigerant, heat sink and flow rate of the Phase-Change Cooling system through the experiments and analyze these results.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.4
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• pp.99-111
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• 2018

Service areas in expressways are very important facilities in terms of efficient expressway operation and the convenience of users. It needs a traffic management strategy to inform drivers in advance about congestion in service areas so as to distribute users of service areas. But due to the lack of sensors and data on numbers of people in the service areas, congestion in service areas had not been measured and managed appropriately. In this study, a congestion index for service areas was developed using telecommunication floating population big data. Two alternative indices (i.e., density of service areas and floating population V/c of service areas) were developed. Finally, the floating population V/c of service areas was selected as a congestion index for service areas for reasons of the ease of understanding and comparison.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.6
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• pp.107-117
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• 2020

With the recent development of autonomous vehicles, various sensors installed in vehicles have become common, and big data generated from those sensors is increasingly being used in the transportation field. In this study, we proposed a grid index method to efficiently process real-time vehicle sensing big data and public data such as road weather. The applicability and effect of the proposed grid space division method and grid ID generation method were analyzed. We created virtual data based on DTG data and mapped to the road link based on coordinates. As a result of analyzing the data processing speed in grid index method, the data processing performance improved by more than 2,400 times compared to the existing link unit processing method. In addition, in order to analyze the efficiency of the proposed technology, the virtually generated data was mapped and visualized.