• Structural Engineering and Mechanics
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• 제62권6호
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• pp.781-788
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• 2017

In this paper, a stress wave model is established to describe the three states (separate, contact and impact) of clearance joints. Based on this stress wave model, the propagation characteristics of stress wave generated in clearance joints is revealed. First, the stress wave model of clearance joints is established based on the viscoelastic theory. Then, the reflection and transmission characteristics of stress wave with different boundaries are studied, and the propagation of stress wave in viscoelastic rods is described by the characteristics method. Finally, the stress wave propagation in clearance joints with three states is analyzed to validate the proposed model and method. The results show the clearance sizes, initial axial speeds and material parameters have important influences on the stress wave propagation, and the new stress waves will generate when the clearance joint in contact and impact states, and there exist some high stress region near contact area of clearance joints when the incident waves are superposed with reflection waves, which may speed up the damage of joints.

• Asia pacific journal of information systems
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• 제8권2호
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• pp.161-172
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• 1998

Marketing information systems become a competitive weapon that supports firms in making decisions on the operation of marketing-related activities. However, little research regarding the operating strategy of marketing information systems has been conducted in Korea. Considering that this issue has been studied in the United States, this paper conducted a global benchmarking on the operating strategy of marketing information systems between Korean and the United States firms. The result of this global benchmarking suggests recommendations on supports from three management levels, the mix of 4P, the management of marketing, data from environment, and information sources.

• Animal Systematics, Evolution and Diversity
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• 제31권4호
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• pp.304-310
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• 2015

Hamaticyclops ahni is described as a new genus and species from the Californian shore of the United States. It was discovered as a victim of the sea anemone Anthopleura elegantissima (Brandt). The new genus is closely related to the genus Hemicyclops but possesses, as significant autapomorphies, three strong claws on the second endopodal segment of antenna and a markedly elongate exopod of leg 5 with its protopod fused to somite.

• Journal of applied mathematics & informatics
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• 제24권1_2호
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• pp.49-64
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• 2007

In this paper, we investigate optimal policies for three age-dependent populations in a competition system, which is controlled by fertility. By using Dubovitskii-Milyutin's general theory, the maximum principles are obtained for problems with free terminal states, infinite horizon and target sets, respectively.

• 한국도서관정보학회지
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• 제27권
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• pp.1-25
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• 1997

The purpose of this paper is to investigate the Korean situation of education for librarianship by comparing library education in the United States of America, the United Kingdom and Korea. The qualifications of librarians, educational institutions and the present trends of education for librarianship in the three countries are described and compared. It was not intended to find out similarities and differences as the three countries share no similar cultural and historical backgrounds. Compared with the education of the two countries, Korea has more ways to qualify librarians, more library schools, and lower academic levels for librarians. Library Associations or Institutes of the U. S. A. and the U. K. are involved in library education by accrediting library schools or library school curricula, but the Korean Library Association has nothing to do with library education. In case of present trends in library education, Korean institutions seem to lag behind in coping actively with the changes occurring in the modern society. Based on the findings, some suggestions are recommended.

• 건축역사연구
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• 제4권2호
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• pp.45-64
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• 1995

This study examines the Section of 'Housing Regulations' in The Chronicles of the Three States (${\ulcorner}$三國史記${\lrcorner}$ 屋舍條) to verify the residential architecture during the period of the Unified Silla Dynasty. Through the study, the basic architectural terms in the Section of 'Housing Regulations', such as the size of the building, glazing roof tile, animal-shaped ornamental piece on roof ridge, eave purlin, wooden bracket arms, roof decoration, decorative paintings, stone steps, wall structure, blind screen, folding screen, bedstead, and gate are analyzed, interpreted and defined, and, in addition, the forms and styles of the residential architecture during the period of the Unified Silla Dynasty are basically reconstructed.

• 한국식생활문화학회지
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• 제1권1호
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• pp.45-53
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• 1986

The utilization of horticultural tools in Korea is historically viewed through limited materials. The garlic shown in the birth myth of the Korean nation appears to be the first record of horticultural foods. Only the fragmentary knowledge is available on the production and utilization of horticultural foods during the eras from Old Chosun to the Three States and the Unified Shilla. It seems that mutual exchange of horticultural foods between the Three States and neighbor countries was very active. Kinds of horticultural foods utilized were more variable in the era of Koryo dynasty. The situation on horticultural foods during Chosun dynasty is comparatively well known through published agricultural books and other literatures.

• 복식문화연구
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• 제10권5호
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• pp.485-492
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• 2002

The purpose of this study is to classify of the Cone shaped Pendants in old tombs of Three Kingdom States. These Cone shaped Pendants are made of bronze and coated with gold plate or Gold. Each Cone shaped Pendants consists of a Sehwhan(細環) type or Taewhan type, a median part in the form of a several joined small globe, or circular shape, and finally a cone-shared pendant. Cone shaped Pendants is 5 part(A-L A-b, B-1-a, B-1-b, B-2-b type) in according to the styles of the Sehwhan(細環) and Taewhan type and median ornament types. A-a, A-b, B-1-a, B-1-b type was general style that was found in most of the old tombs in Kokuryo, Pacjae, ancient Silla. B-2-b type was excavated from the only Kokuryo tombs.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.95-98
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• 2008

In the present work, cross-roil rolling was rallied out using a rolling mill in which the roll axes are tilted by $5^{\circ},\;7.5^{\circ},\;10^{\circ}$ towards the transverse direction of the roiled sample. The evolution of strain states during cross-roll rolling was investigated by three-dimensional finite element method (FEM) simulation. Parallel to cross-roll rolling, normal-rolling using a conventional rolling mill was also carried out in the same rolling condition for clarifying the effect of cross-roll rolling. It turned out that three shear rate components were all introduced to the rolled sample by the cross-roll rolling process, while only one shear rate component operated during normal-rolling.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.404-407
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• 2008

In the present work, cross-roll rolling was carried out using a rolling mill in which the roll axis is tilted by $7.5^{\circ}$ towards the transverse direction of the rolled sample. The evolution of strain states during cross-roll rolling was investigated by three-dimensional finite element method (FEM) simulation. Parallel to cross-roll rolling, normal-rolling using a conventional rolling mill was also carried out in the same rolling condition for clarifying the effect of cross-roll rolling. It turned out that three shear rate components were all introduced to the rolled sample by the cross-roll rolling process, while only one shear rate component operated during normal-rolling.