• Korean Journal of Materials Research
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• v.9 no.9
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• pp.890-895
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• 1999

The recent important issue in solar cell fabrication is to adopt thin film silicon solar cells on cheap substrates. However, thin cells demand new grid design concept that all the contacts(to the emitter and base) be located on the front surface. Hence, the aim of the investigation presented in this paper was to determine the potential and the basic limitation of the design. With this concept, an interdigitated front grid structure was realized and cells were fabricated through a set of photolithography processes. Confirmed efficiencies of up to 11.5% were achieved on bonded SOI wafers with a cell thickness of 50$\mu\textrm{m}$ in the case of finger spacing more than $\mu\textrm{m}$ and a base width of 35$\mu\textrm{m}$. It was also shown from the results that the design rules for optimizing the base fraction and reducing the shadowing fraction are noted as an important technique to realize high-efficiency thin silicon solar cells.

• Journal of the Korean Society for information Management
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• v.17 no.3
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• pp.45-70
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• 2000

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.661-663
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• 2013

The purpose of the following report is to introduce a model that makes it possible to efficiently search data by using keyword-based concept network for reliable access of information which is rapidly increasing in the mobile cloud. A keyword-based concept network is a method with the application of ontology. However, the proposed model is added by association information between keyword concepts as a method for a user's efficient information retrieval. Furthermore, the proposed concept network consists of the keyword centered concept network, expert-group-recommended field concept network, and process concept network.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.1
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• pp.90-96
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• 2011

The shock absorber base assembly is one of the parts in the shock absorber equipment that controls the vehicle movement. It absorbs the shock and vibration to guarantee riding stability and comfort. It demands strength, reliability and strict airtightness of the welded section because the shock absorber base assembly is a container which resists pressure and needs durability by being filled with gas and oil. However, the current engineering needs a lot of production time, has a high cost and shows a low production rate. These problem due to the eight production processes, four of which are spot welding, reinforcement welding like metal active welding (MAG), prior process of the base assembly cap and tube for precision and pressing. We will analyze the manufacturing processes of the base assembly and suggest an improved manufacturing method that uses frictional welding. The results will show that the new method of the frictional welding is better than the previous welding technique. Through the use of this concept of frictional welding, the welding conjunction will be strengthened, measurements will be more precise, and the cost and the number of processes will be reduced.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.502-505
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• 2004

Now for the first time in Korea pilot project on application of base isolation system to the RC building is carrying out by collaboration with KNHC and DRB dongil. The hybrid-type base isolation system, which is composed of sliding bearings and laminated rubber bearings and can make the resonance period of base isolated buildings comparatively long up to 4 or 5 seconds, is applied to this building. In this paper the overview of this project, the dynamic characteristics of this particular building and the response reduction effect against earthquakes are presented.

• Structural Engineering and Mechanics
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• v.16 no.1
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• pp.101-114
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• 2003

A base isolation system is proposed for earthquake protection of structures. The system incorporates spherical supports for the base, a specially designed spring-cam system to keep the base rigidly supported under normal condition and to allow it to move for the duration of the earthquake under the constraint of a spring with optimized non-linear characteristics. A single-story model is constructed to investigate the feasibility of the concept. Numerical simulations of the system as well as experimental results show that 95% reduction of the transmitted force to the structure can be achieved. To demonstrate the effectiveness of this isolation mechanism, the maximum dynamic bending stress developed at predetermined critical points within the frame of the structure is measured. Significant reduction of the dynamic stresses is obtained.

• Honam Mathematical Journal
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• v.34 no.4
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• pp.559-570
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• 2012

We construct a new definition of a base for ordinary smooth topological spaces and introduce the concept of a neighborhood structure in ordinary smooth topological spaces. Then, we state some of their properties which are generalizations of some results in classical topological spaces.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.192-197
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• 2008

High-speed harmonic optical modulation-demodulation schemes are presented and a possibility of the schemes for applying to high-speed light wave transmission system is tested at microwave frequency range. An example of this concept is as follows : Light wave is modulated succeedingly through cascaded optical modulators by a sub-carrier to produce a modulated light wave at harmonic frequency which is higher than the feasible frequency of the individual modulators. For demodulation of the base-band signal, the high frequency optical sub-carrier is down-converted by the same kind of optical modulator with the same concept of harmonic modulation.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.133-137
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• 2002

This paper proposes a way of constructing modern concept of geographic network by interpreting historical geography recorded in old archives such as the Tongdian(通典, Comprehensive Manual) which is one of the important materials in studying old concept of Chinese administrative geography. it is proposed a way of producing geographic network by constructing base network, and by combining and adjusting the constructed networks. The proposed way of construction has been applied for generating a geographic network around Bohai gulf and Sandong peninsula, by using descriptions recorded in the administrative division(州郡典) of the Tongdian.

• Journal of the Korean Society of Costume
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• v.25
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• pp.201-213
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• 1995

The purposes of the study were (1) to seg-ment the female college apparel market based on fashion life style and (2) to develop a pro-file of each segment regard to self-concept, shopping orientation and patronage behavior. The data were collected through questionnaire by random sample of 526 female college students. By cluster analysis of lifestyle factors, three groups were identified, (fashion leaders, fashion followers and fashion aversion) Three groups were then compared through multivariate analysis of variance and chi-square statistics on 10 self-concept variables, 6 shopping statistics on 10 self-concept variables, 6 shopping orientation factors and 1 patronage behavior variable. Significant difference were found among the three groups on all these variables which indi-cate that fashion lifestyle can be a useful base for segmenting female apparel market and these groups are unique in terms of self-con-cept, shopping orientation and patronage behavior.