• 오토저널
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• 제7권1호
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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.

• 대한치과기공학회지
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• 제19권1호
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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.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2010년도 제3회 국제학회
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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.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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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.

• KDI Journal of Economic Policy
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• 제28권2호
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• pp.1-49
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• 2006

가구원의 연령 및 성별, 가구원 수 등 인구학적 특성이 가계의 소비구조에 영향을 미친다는 점을 고려할 때, 급격한 인구구조 변화는 우리나라 전체의 가계소비지출 구성에 지대한 영향을 미칠 것으로 짐작된다. 인구학적 특성의 변화가 소비지출에 미치는 영향을 분석하기 위하여 본 논문에서는 가계소비지출 통계자료에 Quadratic Almost Ideal Demand System(QUAIDS) 모형을 적용하여 소비지출 항목별 구성비 함수를 추정하였으며, 경제 성장률, 인구, 가구구성 등 추정에 사용된 설명변수들의 전망치를 이용하여 2005~2020년 기간 중 우리나라 가계소비지출의 구성 변화를 전망하였다. 전망 결과에 따르면, 우리나라의 가계소비지출은 향후에도 상당한 변화를 보일 것이며, 이 가운데 많은 부분은 인구학적 특성 변화에 기인하는 것으로 분석되었다. 소비구조의 변화는 산업구조의 변화를 야기한다. 따라서 자원의 효율적 배분을 위해서는 생산요소의 유연한 산업 간 이동을 촉진하기 위한 정책적 노력이 필요하다. 한편, 본 논문의 전망 결과는 기업의 투자계획 수립에 있어 유용한 정보로 사용될 수 있다.

• 한국표면공학회지
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• 제45권3호
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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.

• 대한한의학원전학회지
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• 제23권1호
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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.

• 대한추나의학회지
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• 제6권1호
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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.

• 건축역사연구
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• 제33권2호
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• pp.7-15
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• 2024

The composition of the upper structure, which can be found in the 3-Dori type buildings in Yang-dong Village, varies significantly from time to time. The upper structure of the Gwan-ga-jeong, known as a house in the mid-Joseon Dynasty, consists of a basic 3-Dori type structure in which a beam is placed under 3-Dori and supported with two flat columns. On the other hand, the upper structure of I-hyang-jeong historic house, built in the 17th century, is different in that it has a stud between the two flat columns. The upper structure of Sa-ho-dang historic house, a 19th-century building is different from the upper structure of the buildings of the previous period in that three flat columns were used. As such, the difference in the composition method of the upper structure according to the construction period is closely related to the introduction of the Toi-maru, which is mainly explained by the boundary space. In addition, it can be expected that the introduction of the Toi-maru originated from the influence of the change in the plan. This study was conducted to examine the correlation between the plan and the composition of the boundary space through various typology of the 3-Dori upper structure distributed intensively in Yang-dong Village.

• Natural Product Sciences
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• 제25권2호
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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.