• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1506-1511
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• 2003

The present study proposes a new structure for a flat plate heat pipe which could embody a thin thickness, any shapes and high heat density a unit area. It is on the structure for the formation of vapor passages and the support of the case of the flat plate heat pipe. A screen mesh is used as the one. To verify the validity of the one, the flat plate heat pipe of 1.08mm thickness was made with a layer of the screen mesh with 14 and 100 mesh number respectively and tested. Here the screen mesh with 14 mesh number plays a role of the vapor passage and the support of the case and the screen mesh with 100 mesh number functions as the wick structure. T he results show that the screen mesh excellently carries out the function of the vapor passage and the support of the case.

• The Journal of Pediatrics of Korean Medicine
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• v.30 no.4
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• pp.111-122
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• 2016

Objective The purpose of this study is to investigate recent clinical studies on the effect of herbal medicine in flat warts in China, and to seek better methods to treat and study for flat warts in Korea. Methods The clinical studies from the CAJ (China Academic Journal) of CNKI (China National Knowledge Infrastructure) by key words '扁平疣' in recent 5 years (From January 2011 to December 2015) were searched. Results 16 articles were selected from 122 clinical studies, and analyzed. The most commonly used herbs were Isatidis Radix (板藍根), Equiseti Hiemalis Herba (木賊), Cyperi Rhizoma (香附子), Carthami Flos (紅花), Glycyrrhizae Radix (甘草) etc., and the articles all showed effectiveness over the control group. Conclusion Based on analyzing the studies, herbal medicine has shown effective in flat wart. This study may be useful not only as clinical data, but also to determine better treatment going forward.

• Ocean and Polar Research
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• v.22 no.1
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• pp.15-23
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• 2000

The community structure of meiobenthos was studied in tidal flats of Kanghwado in November, 1997. Nematodes were the most dominant group among 18 total meiofaunal groups at most stations except for at lower tidal flats where the most abundant groups were harpacticoid copepods. Meiobenthos were the most abundant in the upper 1cm and their density decreased depending on the depth from the surface. The highest density of the meiobenthos was 6,094 inds. $10cm^{-2}$ at the upper tidal flat, while the lowest was 1,524 ind. $10cm^{-2}$ at the lower tidal flat. The density was higher in general at the upper tidal flats, but decreased at the stations toward lower tidal flat at all transect lines. At all transect lines, nematodes decreased as stations were along toward lower tidal flat whereas harpacticoids increased. The values of N/C(nematodes/benthic harpacticoids) ratio were higher at the upper tidal flats than the lower tidal flats at all transect lines.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.124-129
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• 1999

In this study, a design method for the flat sound radiator is developed to make new sound radiator system, whose shape is much thinner than that of conventional loudspeaker. Piezofilm (PVDF) is used as actuators of flat sound radiator. To avoid the distortion of sound radiated from flat sound radiator, the frequency response of radiated sound to be flat is taken as the design objective. The electrode pattern and orientation angle of piezofilm actuator is optimized to satisfy the design objective. The formulation is based on the coupled finite element and boundary element method. Genetic algorithm is used in the optimization process, which is useful in the optimization of discrete design variables. Frequency response with optimized piezofilm actuator is made flat enough to satify the design objective. For the enhancement of sound power, double-layered piezofilm actuators are also considered. The sound power with double-layered actuator becomes larger than that with single-layered actuator as expected.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.203-210
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• 2005

This paper summarizes full-scale test results on CFT column to flat plate connections subjected to gravity loading. CFT construction has gained wide acceptance in a relatively short time in domestic building practice due to its various structural and construction advantages. Constructing the floor as flat plate is often regarded as being essential for both cost savings and rapid construction. However, efficient details for CFT column to flat plate connections have not been proposed yet, and their development is urgently needed. Based on some strategies that include maximizing economical field construction, several connecting schemes were proposed and tested in this study. Test results showed the proposed connection details can exhibit strength and stiffness comparable to or greater than those of R/C flat plate counterpart.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.6
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• pp.880-887
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• 1998

In order to study heat transfer characteristics of spray cooling for the purpose of uniform and soft cooling of high temperature surface a series of experiments for a hot horizontal copper flat plate was performed by downflow spray water using flat spray nozzle. Cooling curves were mea-sured under the various experimental conditions of flow rates and temperatures of cooling water Surface temperature surface heat fluxes and heat transfer coefficients of horizontal upward-facing flat surface were calculated with cooling curves measured at each radial positions near the cooling surface by TDMA method. Generally heat transfer characteristics for spray cooling is simi-lar to boiling phenomenon of pool boiling. The minimum heat flux(MHF) appear at the surface temperature of about ${\Delta}Tsat=250^{\circ}C$ and the critical heat flux(CHF) appear at about ${\Delta}Tsat=250^{\circ}C$.

• Journal of the Korean Mathematical Society
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• v.40 no.1
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• pp.109-128
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• 2003

In this paper, we show that the Euler characteristic of an even dimensional closed projectively flat manifold is equal to the total measure which is induced from a probability Borel measure on RP$^{n}$ invariant under the holonomy action, and then discuss its consequences and applications. As an application, we show that the Chen's conjecture is true for a closed affinely flat manifold whose holonomy group action permits an invariant probability Borel measure on RP$^{n}$ ; that is, such a closed affinly flat manifold has a vanishing Euler characteristic.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.30-31
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• 2016

Recently in the construction site is required various performance of mortar to deal with reliability, economy. Especially of environment-friendly, saving resources and high performance of mortar it began to require improvement of performance. Therefore, in this study, a series of tests was designed to develop a using mud flat mortar in view of the high absorption rate of tidal flats, to fix the water cement ratio to 70%. The mixing ratio were 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6 of fine aggregate and mud flats. Compared the flow value, chloride content, compressive strength, tensile strength, and workability of fine aggregate the substituted mud flat mortar and basic cement mortar, present the basic data on the characteristics and effects of mud flat mortar.

• Korean Management Science Review
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• v.26 no.1
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• pp.21-35
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• 2009

There is a controversy on Internet pricing, flat-rate vs. usage-based. This study gives a comparative analysis between flat-rate and two-part tariff which is realistic alternative of usage-based pricing. In a basic economic model, two-part tariff based on ISP's cost structure satisfies allocative efficiency and relatively expand the number of subscribers. But the characteristics of Internet service like consumers' uncertainty on cost, measurement cost of traffic and network externality induce increase of cost or decrease of marginal utility. The analysis shows that small impact of these can make flat-rate more efficient.

• Journal of Korean Vacuum Science & Technology
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• v.3 no.1
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• pp.30-32
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• 1999

Electron beam trajectory simulation results on the high voltage FED with cone-type field emitters predict that the cross-talk phenomena would be seen due to the divergence of the electron beam. In this study, computer simulations with design of experiment technique and the SNU-FEAT program were carried out for five input parameters of the aperture focusing structure. The results tell that the focusing voltage is a dominant factor. And, the beam divergence index could be reduced to 10.7$\mu\textrm{m}$ with the aperture focusing structure, however, the operating voltage of the field emitter is predicted to increase by 40% maximum.