• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.24-34
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• 1985

The study of unsteady gas exchange processes in the inlet and exhaust systems of the single-cylinder 4-stroke cycle spark ignition engine is presented in this paper. The generalized method of characteristics including friction, heat transfer, change of flow area and entropy gradients was used for solving the equations defining the gas exchange process. The path line calculation was also conducted to allow for calculation of the gas composition and entropy change along the path lines, and of the variable specific heat due to the change of temperature and composition. As the result of the simulation, the properties at each point in the inlet and exhaust pipe, pressure and temperature in the cylinder, and charging efficiency were obtained. Pumping loss and residual gas fraction were also computed. The effect of engine speed, exhaust and inlet pipe length on the pumping loss and charging efficiency were studied showing that the results were in agreement with what has been known from experiments.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.120-121
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• 2009

We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.13-19
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• 1997

The purpose of this study was carried out by oberserving to composition of an oxide on the surface of Dental porcelain alloy according to the conditions of its heat treatment and analysing the change composition on its surface. Morphological change of the heat treated dental porcelain alloy have been investigated with SEM and EDX. The result of this study is summarized ad follows. The surface indium concentration of specimens increased as the heat treatment temperature and the oxygen partial pressure increased.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.80-81
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• 2010

We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

• KDI Journal of Economic Policy
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• v.28 no.2
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• pp.1-49
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• 2006

Considering the fact that households' demographic characteristics affect consumption decision, it is conjectured that rapid demographic changes would lead to a substantial change in the composition of private consumption expenditure. This paper estimates the demand functions of various consumption items by applying the Quadratic Almost Ideal Demand System(QUAIDS) model to Household Income and Expenditure Survey data, and then provides a long-term forecast of the composition of household consumption expenditure for 2005-2020. The paper shows that Korea's consumption expenditure will maintain the recent years' rapid change, of which a considerable portion is due to rapid demographic changes. Results of the paper can be utilized in forecasting the change in the industrial structure of the economy, as well as in firms' investment planning.

• Journal of the Korean institute of surface engineering
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• v.45 no.3
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• pp.136-141
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• 2012

'Jikjisimcheyocheal (Jikji afterwards)' is known as a first book printed by the metal type in the world. The metal type used for printing this book has not been found yet. To help for replicating the original metal type, it is required to investigate the composition analysis of the copied metal type. In this study, the composition analysis and thermodynamic care for replicating of ancient metal type was performed on the basis of an analytical reports concerned with the ancient metal type which made after Jikji printing. Metal types were made by remelting and casting of the mother alloy which came from a cast of a mixed metals in accordance with the composition revealed in the literatures. Change of composition during remelting of mother alloy and casting of metal was detected by the EDS analysis. The reasons for variation in composition were discussed by metallurgical and thermodynamic point of view, and a mixing ratio of metals to get the original composition of ancient metal type is suggested. Some attention should be paid on mixing, melting and casting of metals to get an objected composition for copy of ancient metal type.

• Journal of Korean Medical classics
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• v.23 no.1
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• pp.203-215
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• 2010

Music is composed according to time flow. In case of music therapy, it is the most important thing and this properties must be emphasized in operation, also act as one of the most important elements that increase the effect of medical treatment. Especially in the case of Oriental Medical music therapy, we must consider the change of time and space, so determine the direction and methods of treatment. In order to compose the music therapy process according to time flow[plot composition], first we have to analyze the musical and literary works that have step-by-step composition. Next we must consider how Gi(氣) changes occur in the base of principle of Eumyang(陰陽) and Ohaeng(五行). When the rule of composition as time flow is grafted onto Oriental Medical music therapy, native characteristics of music would have significance.

• The Journal of Korea CHUNA Manual Medicine
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• v.6 no.1
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• pp.11-20
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• 2005

Objectives: To find relation with training period and body composition of peoples engaged in training program of six weeks and present a better training formula. Methods: Changes of body composition during training were analysed with paired t-test. correlation of training period and body composition were analysed with simple correlation analysis. Results: Body weight, body fat and body fat ratio were decreased significantly, all of them were concerned in training period. Conclusions: Training program of six weeks reduce body weight, body fat ratio even muscle mass. It should be careful to order training prescription.

• Natural Product Sciences
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• v.25 no.2
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• pp.81-91
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• 2019

Marrubium vulgare, plant species belonging to Marrubium genus, is widespread in the Mediterranean areas, introduced elsewhere and also cultivated in many countries. Its oil is recognized to possess a considerable biological activities with varied chemical composition. This paper aims to overview the chemical composition and biological activities of M. vulgare essential oil's considered as a medicinal plant, widely used in folk medicine overall the world. In essential oils of M. vulgare, germacrene D, ${\beta}$-caryophyllene, ${\beta}$-bisabolene, bicyclogermacrene and carvacrol are generally considered as either mains or minor constituents and each species presents its own composition. Sesquiterpenoids were the dominant fraction while monoterpenoids were present in appreciable or in trace amount. Oxygenated fractions dominated in monoterpenes however, hydrocarbon fraction overpowered in sesquiterpenes. These oils are biologically active, they exhibit an antioxidant and antimicrobial activities and other activities. Due to the variability of composition of essential oil, further studies are necessary, particularly regarding their chemical's which may cause an important change in the biological activities of oils and probably defined different chemotype.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3509-3513
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• 2014

Phospholipase D (PLD) catalyzed the generation of phosphatidic acid (PA) from phosphatidylcholine (PC) at the outer layer of the vesicles prepared through layer by layer via a double emulsion technique. The generation induced a curvature change in the vesicles, which eventually led them to fuse each other. The ratio of two-fatty-acid-tail ethanolamine (PE) to one-fatty-acid-tail ethanolamine (PE) was found to acquire the condition where the mixed-phospholipid vesicles were stable identically with pure two-fatty-acid-tail PC. The effect of the outer-layer mixture on the PLD-induced vesicle fusion was investigated using the fluorescence intensity change. 8-Aminonaph-thalene-1,3,6-trisulfonic acid disodium salt (ANTS) and p-Xylene-bis(N-pyridinium bromide) (DPX) were encapsulated in the vesicles, respectively, for the quantification of the fusion. The fluorescence scale was calibrated with the fluorescence of a 1/1 mixture of ANTS and DPX vesicles in NaCl buffer taken as 100% fluorescence (0% fusion) and the vesicles containing both ANTS and DPX as 0% fluorescence (100% fusion), considering the leakage into the medium studied directly in a separate experiment using vesicles containing both ANTS and DPX. The fusion data for each composition were acquired with the subtraction of the leakage from the quenching. From the monitoring, the vesicle fusion caused by the PLD reaction seems dominantly to occur rather than the vesicle lysis, because the composition effect on the fusion was observed identically with that on the change in the vesicle structure. Furthermore, the diameter measurements also support the fusion dominancy.