• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.6
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• pp.538-543
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• 2008

Nanostructured materials are attracting increased interest and application. Exciting perspectives may be offered by electrical insulation. Epoxy/Organoclay nanocomposites may find new and upgraded applications in the electrical industry, replacing conventional insulation to provide improved performances in electric power apparatus, e.g, high voltage motor/generator stator winding insulation, dry mold transformer, etc. In the paper work, the electrical and thermal properties of epoxy/organoclay nanocomposites materials were studied. The electrical insulation characteristics were analyzed through the permittivity characteristics. by analyzing the permittivity spectra, it was found that dielectric constant becomes smaller with increase frequency and becomes larger with increase temperature. This indicates restriction of molecular motion and strong bonds at the epoxy/organoclay nanocomposites. The morphology of nanocomposites obtained was examined using TEM and X-ray diffraction. It has been shown that the presence of polar groups leads to an increased gallery distance and partial exfoliation. Nevertheless, full exfoliation of clay platelets has not been achieved.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1139_1141
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• 2009

Distributed Generation (DG) is predicted to play a important role in electric power system in the near future. insertion of DG system into existing distribution network has great impact on real-time system operation and planning. It is widely accepted that micro turbine generation (MTG) systems are currently attracting lot of attention to meet customers need in the distributed power generation market In order to investigate the performance of MT generation systems, their efficient modeling is required. This paper presents the modeling and simulation of a MT generation system suitable for grid-connected operation. The system comprises of a permanent magnet synchronous generator driven by a MT. A brief description of the overall system is given, and mathematical models for the MT and permanent magnet synchronous generator are presented. Also, the use of power electronics in conditioning the power output of the generating system is demonstrated. Simulation studies with MATLAB/Simulink have been carried out in grid-connected operation mode of a DG system. The control strategies for grid connected operation mode of DG system is also presented.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.05a
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• pp.63-64
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• 2006

The design concept of this dental clinic Interior design is emotional color expression for the medical facility. This dental clinic is showing off the new adoption of the Korean primary traditional color pallette for the medical interior design. The graphic wall of the corridor is strongly attracting the eyes of customers while wrapping the corridor wall and partition with rather unconventional primary colored graphic shaping a tooth. Also the vivid and the dynamic atmosphere are emphasized by using the red color in the treatment area and the powder room. For the space programing, I focused on the functionality of each space and the efficiency of the traffic line. Centering around the information desk, the principal traffic line Is divided Into the staffs' private movement and the public movement.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.11
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• pp.1813-1819
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• 2016

In this paper, LS-SynRM (Line Start-Synchronous Reluctance Motor) has been attracting attention in replace of induction motor which hardly provides high efficiency. Compared to induction motor, LS-SynRM has better efficiency per unit area. This study demonstrated the electromagnetic design methods of LS-SynRM while maintaining the frame of existing IE3 induction motor for blower. We documented the design procedures for generating high saliency which is the most essential and mechanical stress analysis is also treated. In conclusion, we proved the validity of our design by manufacturing and testing our LS-SynRM models.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.119.2-119.2
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• 2011

Dye-sensitized solar cells (DSSC) are currently attracting wide spread academic and commercial interest for the conversion of sunlight into electricity because of their easy manufacturing process and high efficiency. The solar energy conversion efficiencies of DSSC are strongly dependent on dye molecules adsorbed on the TiO2 surface which used for photosensitization of sun light, since an excited state of dye could inject an electron into the conduction band of semiconductor. We have developed novel organic dyes which have phenothiazine moieties as an electron donor in their charge-transfer chromophore for application of DSSCs. We had synthesized a series of phenothiazine derivatives which have different wave length absorbing chromophore in the molecule with high molar extinction coefficient. The photovoltaic performance of DSSC composed of organic chromophores with broad wavelength absorption property were measured and evaluated by comparison with that of pristine ruthenium dye.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2000.05a
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• pp.110-114
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• 2000

This paper shows the possibility of performing the friction stir welding and the development of optimizing tools for FSW with 2mm thick plate of aluminum alloys using milling machine. This research can be reported on achieving above 90% of the tensile strength in 1050 aluminum alloys friction stir welded in the room temperature. This welding process is very simple and does not require filler metal eliminates straightening of the workpiece. It is currently attracting interest from different industries working with aluminum alloys.

• Korean Management Science Review
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• v.23 no.2
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• pp.75-91
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• 2006

The purpose of this paper is to propose a new software development cost estimation method using SVR(Support Vector Regression) SVR, one of machine learning techniques, has been attracting much attention for its theoretic clearness and food performance over other machine learning techniques. This paper may be the first study in which SVR is applied to the field of software cost estimation. To derive the new method, we analyze historical cost data including both well-known overseas and domestic software projects, and define cost drivers affecting software cost. Then, the SVR model is trained using the historical data and its estimation accuracy is compared with that of the linear regression model. Experimental results show that the SVR model produces more accurate prediction than the linear regression model.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.19-24
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• 2012

Robots have been attracting students' interest recently. Therefore, they are a good way to motivate to study related subjects. However, there are difficulties in teaching general students because a wide background is required to understand the fundamentals of robotics. In order to teach robotics fundamentals to beginners in a short period, an effective experimental class, including several phased experiments, is proposed in this paper. A portable two-DOF robot arm system with servo motors was developed for experiments, and the operation method based on kinematics was introduced for its operation. The effectiveness of the class was investigated by using a questionnaire after carrying it out in a university class for junior students.

• Journal of the Korea Furniture Society
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• v.17 no.2
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• pp.1-7
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• 2006

A chinese wood species called China Hongmu, is an excellent wood to make high quality furniture owing to attracting color, beautiful grain, and durability. Hongmu is not a tree or wood species name. The general designation in Hongmu group is a similar to one of its density, structure, color and use. Hongmu considers more than 30 hardwood species of Pterocarpus, Dalbergia, Diospyros, Millettia, and Cassia. According to the macrostructural characteristics and properties, Hongmu group can be classified into 8 groups which are Zitanmulei, Hualimulei, Heisuanzhimulei, Hongsuanzhimulei, Xiangzhimulei, Wumulei, Tiaowenwumulei and Jichimulei. In this paper, the growing areas, scientific names and identifiable characteristics of these Hongmu group species were introduced for help to identify China Hongmu and its products in the market as well.

• The Korean Journal of Health Service Management
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• v.7 no.3
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• pp.225-235
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• 2013

This study purposed to analyze the productivity of regional medical capacity in attracting medical tourist between 2009 and 2011. Data envelopment analysis (DEA) and Malmquist productivity index (MPI) were applied to test the productivity and changes in study periods. The DEA model included a number of doctors, nurses, and beds as input factors, and a number of inpatient and outpatient, and hospital income as output factors. The result of the study were as follow. Jeju had efficiency value of 1 for three years. Seoul, Busan, Daegu, Daejeon, Ulsan, Gyeonggi, Gangwon, Jeonnam, Gyeongbuk, and Gyeongnam showed an increasing trend of efficiency value over three years. Seoul had the efficiency value, 1, in 2011. But, Incheon, Gwangju showed decreasing efficiency score during the study period. MPI showed overall productivity decrease during the period. Further studies will be needed by collecting more time-series data.