• Journal of Ginseng Research
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• v.27 no.3
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• pp.141-145
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• 2003

The multi-year production cycle for ginseng can be rapidly depreciated by inferior post-harvest activities. This research examines the character of high temperature drying regimes for North American ginseng root to assist management decision making. The objective is a very rapid drying regime, that will not result in physical or chemical damage to the root and that would not alter the actual dry root weight. Research is presented using drying temperatures of 55, 70 and 105 C. Temperatures above these rapidly cause substantive physical damage to the root samples and seriously compromise the dry root values determined. Temperatures below these behaved quite similar to actual dryer regimes (approximately 38 C). Laboratory results indicate that there are differences between the three temperature regimes tested. Careful usage of the 70 C regime, over a period of two to three days in a convection drying oven, has distinct merit.

• 보존과학연구
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• s.22
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• pp.133-154
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• 2001

Stone cultural properties, exposed in natural environment, is deteriorated by many weathering reasons for a long time. It is necessary to treat of consolidation and water-repellent on the surface because of the conservation of stone cultural properties. We was treated the specimen [granite(Hwangdung-suk), sandstone, marble(in JeongSeon)] by synthesis resin of DWR-Ⅲ, SI2121 and fluoropolymer, and tested on the durability, water-repellent, color stability and luster generation etc. In the result of this study, DWR-Ⅲ and fluoropolymer is superior to the waterrepellent, durability of salt and acid rain. SI2121 is superior to the penetration because of lower viscosity, but the water-repellent is inferior to the others. After the treatment of chemicals, the color-variation make an appearance but luster-generation doesn’t. With the passage of time, the color of specimen was got better because of the ‘washing’ phenomenon for ultra-violet, salt etc.

• Tribology and Lubricants
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• v.1 no.1
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• pp.80-87
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• 1985

Lithium dual complex grease was prepared through the second continuous saponification reaction of a complex gellant system whose essential components comprised of a selected hydroxy fatty acid, lithium hydroxide monohydrate and boric acid to have a fiber structure of chemical, thermal and mechanical stability at high temperatures. An optimum amount of complex gellant was found to be 14% (NLGI #2), and an addition of castor wax of 1.5% provided an excellent performance properties, especially. The oil separation, oxidation stability, water wash-out property, shear stability, extreme pressure and wear property of thus prepared were tested by the ASTM and KS methods, and a characteristic result was obtained.

• Journal of the Korean housing association
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• v.20 no.1
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• pp.45-58
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• 2009

This research starts from the questioning of current housing development on the hilly site in Korea. It aims to investigate various design techniques of low-rise housing as an alternative housing plan on hilly sites. Several generic solutions of the combination of building type and road pattern are tested for a simulation process, and evaluated in terms of crucial design issues; development density, parking space and open space. As a result, four reasonable models are selected for making full use of geographical features of hilly site, two models each land slope of $18^{\circ}$ and $26^{\circ}$. Several design techniques for each model are also suggested, in ensuring the development feasibility by considering land slope, vehicular access and parking, common open space, and community facilities.

• Korean Journal of Hydrosciences
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• v.6
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• pp.51-66
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• 1995

Various Eulerian-Lagerangian numerical models for the one-dimensional longtudinal dispersion equation are studied comparatively. In the models studied, the transport equation is decoupled into two component parts by the operator-splitting approach ; one part governing advection and the other dispersion. The advection equation has been solved using the method of characteristics following flud particles along the characteristic line and the result are interpolated onto an Eulerian grid on which the dispersion equation is solved by Crank-Nicholson type finite difference method. In solving the advection equation, various interpolation schemes are tested. Among those, Hermite interpo;ation po;ynomials are superor to Lagrange interpolation polynomials in reducing both dissipation and dispersion errors.

• International Journal of Contents
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• v.8 no.2
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• pp.43-51
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• 2012

This study identifies the determinants of increasing privacy concerns in the mobile apps. The privacy affecting factors will be divided into the 3 categories on the basis of both users' and developers' perspective. First, this study explores whether the users' seeking value affects concern of the mobile apps privacy. Second, gender gap on the mobile privacy sensitivity will be tested. Third, this study identifies the meaning of apps developers' providing toolkit in the users' sensitivity on the privacy. The result showed that innovation among the customer's characteristics was identified the most significant factor to affect the mobile app privacy sensitivity. Ethical norm related variables (ethical identity, subjective norm and utilitarian value) were also identified as the meaningful variables in the mobile app privacy. Toolkits provided by app developers are also appeared a significant variable to affect the customer's app privacy sensitivity negatively. Finally gender also appears the meaningful factor in the mobile app privacy sensitivity.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.939-950
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• 2011

In this study, the load test of rubber tire bogie for monorail type LRT. Bogie for rolling stock in safety operation of the vehicle as an essential core unit before applying to the vehicle safety and reliability should be tested sufficiently. Rubber tire monorail type bogie compared to the traditional bogie wheel lots of formats, the complexity of the load acting static load test, the bogie of the vehicle operation conditions by structural analysis by considering the loading conditions was evaluated by calculating. Test methods and evaluation criteria based on urban rail vehicle performance testing by applying the test were welded parts and materials for the results leading to material fatigue endurance test by applying the result of evaluating the structure has been identified as safe.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.61-66
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• 2008

For the production of urethane prepolymer, the effect of process parameters such as diisocyanate MDI and polyol TDI was tested. In this paper, design of experiments has been adopted for studying the effect of the process parameters on the improvement of NCO and viscosity of pre-polymer. As a result of comparison of different parameters, the effect of polyol was stronger than that of isocyanate in comparison of reactivity according to the amounts of isocyanate and polyol. Especially, NCO and viscosity of pre-polymer affected a product safety.

• International Journal of Concrete Structures and Materials
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• v.8 no.2
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• pp.165-172
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• 2014

Recycled coarse aggregate (RCA) made from waste concrete is not a suitable structural material as it has high absorption of cement mortar, which adheres on the aggregate surface and on the tiny cracks thereon. Therefore, when using RCA made from waste concrete, much water must be added with the concrete, and slump loss occurs when transporting. Hence, its workability is significantly worse than that of other materials. In this study, surface of RCA was coated with water-soluble polycarboxylate (PC) dispersant so that its characteristics improved. Each possibility was evaluated: whether its slump loss can be controlled, by measuring its workability based on the elapsed time; and whether it can be used as a structural material, by measuring its strength. Moreover, the carbonation due to cement mortar adhesion was measured through a carbonation test. As a result, RCA coated with PC dispersant was found to be better than crushed coarse aggregate and RCA when the physical properties of the fresh concrete and the mechanical, durability of the hardened concrete were tested.

• KIEAE Journal
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• v.7 no.2
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• pp.71-76
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• 2007

For the many years the children's running noise has caused perpetual frictions between neighbors in apartment houses. For this reason the government established a regulation to reduce the floor impact noise, as a result almost all apartment houses have been enforced to use the floor structure with 210mm thickness concrete slab and 120mm thickness of floor heating system since July 2005. If do not want to apply this kind of system, a system which obtain the certification from the institution appointed by government must be applied. In this reason a lot of construction material companies and construction companies have been trying to develop the system with 180mm thickness concrete slab for the purpose of reducing the cost. To develop the optimized floor system, actual size test building were constructed and the materials related with reducing floor impact noise were composited and tested in the test building. Through this procedure the most effective system was found.