• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.629-632
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• 2009

We have proposed a novel viewing angle controllable display of in-plane switching (IPS) mode with single panel. One pixel of this device is divided to two regions, in which main pixel shows image and sub pixel for viewing angle control. In initial state, the liquid crystal of sub pixel is homogeneous aligned on substrate for wide viewing angle mode. On the other hand, after applying voltage, the liquid crystal of sub pixel tilts up for narrow viewing angle mode. The proposed device has advantage for the function for simple manufacturing process and good viewing angle control with single panel.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.4
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• pp.161-167
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• 2000

This paper presents a new methodology that can evaluate transfer capability of composite power systems from the adequacy point of view in power system planning stages. First of all, to evaluate practical load supplying capability, nonlinear optimization problems of maximum load supplying capability(MLSC) and economic load supplying capability(ELSC) are formulated and solved by nonlinear primal-dual interior point method. Here, physical constraints considered in the optimization problems are the limits of bus voltage, line overloading, and real & reactive power generation. Also, an evaluation method of transfer capability is presented based on margins calculated by the MLSC and ELSC. Especially, to evaluate transfer capability flexibly, simple indices such as expected MLSC, transfer capability margin, and power not supplied are respectively proposed by considering (N-1) line outage probability. Numerical results on IEEE RTS 24, IEEE 118, and IEEE 300 bus system show that the proposed algorithm is effective and useful for power system planning stages.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.234-235
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• 2015

In South Korea, small photovoltaic equipment is increasingly adopted in more detached houses on the constant basis. With this broader use of small photovoltaic equipment, its systematic maintenance becomes all the more necessary. However, photovoltaic facility maintenance has been concentrated solely on large-scale solar energy generation plants in the country while hardly covering smaller facilities. In this research, the JEM rule and extant maintenance company services were analyzed to develop a proper maintenance model for small photovoltaic equipment. The maintenance service procedures designed herein are as follows: A small photovoltaic equipment user chooses a maintenance company and signs a contract. Once a contract is made, the Korea Energy Management Corporation provides a certain kind of incentive to the company. The company provides maintenance service to the user and receives a service fee. If such a maintenance service model is in place, small photovoltaic equipment efficiency is expected to increase and users could receive systematic maintenance services. Also the new creation of small photovoltaic equipment maintenance service would form a new market to generate more jobs for the society.

• Structural Engineering and Mechanics
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• v.24 no.6
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• pp.665-682
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• 2006

A vibration-based nondestructive damage evaluation technique for a curved thin beam is introduced. The proposed method is capable of detecting, locating, and sizing structural damage simultaneously by using a few of the lower natural frequencies and their corresponding mode shapes before and after a small damage event. The proposed approach utilizes modal flexibilities reconstructed from measured modal parameters. A rigorous system of equations governing damage and curvature of modal flexibility is derived in the context of elasticity. To solve the resulting system of governing equations, an efficient pseudo-inverse technique is introduced. The direct inspection of the resulting solutions provides the location and severity of damage in a curved thin beam. This study confirms that there is a strong linear relationship between the curvature of modal flexibility and flexural damage in the selected class of structures. Several numerical case studies are provided to justify the performance of the proposed approach. The proposed method introduces a way to avoid the singularity and mode selection problems from earlier attempts.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.99-105
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• 2006

Polyamine dendrimers functionalized with electrochemiluminescent (ECL) polypyridyl Ru(II) complexes, dend-$[CO-(CH_2)_3-mbpy{\cdot}Ru(L)_2]_3(PF_6)_6$ (dend: N$(CH_2CH_2NH)_3$-, L: bpy, o-phen, phen-Cl, DTDP), were synthesized through the complexation of dendritic polypyridyl ligands to Ru(II) complexes. Their electrochemical redox potentials, photoluminescence (PL), and relative ECL intensities were studied. The ECL emissions produced by the reaction between the electro-oxidized $Ru^{3+}$ species of polyamine dendrimers and tripropylamine as a coreactant were measured in a static system with potential cycles between 0.8 and 1.3 V or through flow injection analysis with a potential of +1.3 V, and were compared to that of $[Ru(o-phen)_3](PF_6)_2{\cdot}Dend-[CO-(CH_2)_3-mbpy{\cdot}Ru(bpy)_2]_3(PF_6)_6$ showed an ECL intensity that was two-fold greater than that of the reference complex $[Ru(o-phen)_3](PF_6)_2$.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.1
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• pp.219-236
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• 2009

Background : Recently the number of atopic dermatitis patients has increased, but the treatment of atopic dermatitis is not effective, and the recurrence rate of atopic dermatitis is high. Many patients are suffering from pruritus. A new standard treatment system is needed. Objective : This study investigated the effect of Oriental medicine program for atopic dermatitis patients during short term hospitalization. Method : 6 patients were admitted for short term hospitalization program. The program includes Acupuncture, herbal medicine, examination, education, cupping therapy, herbal dressing, exercise and etc. Everyday we evaluated the patients by Severity Scoring Atopic Dermatitis(SCORAD) index and took the photos of lesions, and the patients evaluated themselves by atopic dermatitis diary which consists of emotion, pruritus, sleep loss. Results : Admission duration was 7 to 14 days. The SCORAD scores of them were decreased. Most symptoms of 6 patients were improved. Especially herbal dressing was effective for severe oozing. Subjective scores of atopic dermatitis diary were reduced. Conclusion : We expect that the short term hospitalization program could be helpful for uncontrollable atopic dermatitis patients.

• KIEAE Journal
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• v.11 no.2
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• pp.9-15
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• 2011

Many Korean palaces such as Deoksu Palace and Kyungbok Palace are located in downtown Seoul. Modern high-rise buildings around the palace have been the background scenery of traditional architecture in it. In this case, such landscapes mixed with traditional images and contemporary images can give a negative impression to visitors watching from inside the palace. In this study, we analysed the correlation between landscape image of Deoksu Palace and trees' view blockage of buildings around it with three independent variables. The first variable is completely blocked view of buildings around the palace by the trees. The second variable is half-blocked view of buildings around the palace by the trees. The third variable is the view of buildings around the palace that is not blocked by the trees. The analysis showed that there were some significant correlations between landscape image of Deoksu Palace and trees' view blockage of buildings around it. It also showed that the view blockage ratio by the trees has positive correlation with improvement of landscape image of the palace.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.1
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• pp.37-44
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• 2002

This Paper suggests reasonable pricing mathod fur Reactive Power in Optimal Power Flow for the system analysis. Under restructuring, not only real power pricing but also reactive power pricing is important for the system analysis and operation. If people just focus on real power pricing, the Generators may no generate reactive power voluntarily, because the Generators may not recover the cost of the reactive power generation. So making a reasonable reactive power pricing is becoming more important than any other time. In this paper, the authors set a Proper Power factor and price the portion of the reactive power that exceeds the power factor using Interior Point Method. By applying this method, the System operator can use this strategy for the analysis of reactive power generation pricing and the Generator can get the motivation to generate reactive power. The author develops fully optimized fast Primal Dual Interior Point Method with sparsity technique and applies this method to Reliability Test System (RTS24) and KEPCO 674 bus system (684 buses. 1279 lines). It shows adaptability and usefulness.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.893-898
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• 2014

Recently, the interior permanent synchronous motor (IPMSM) has been applied to an integrated starter and generator (ISG) for hybrid electric vehicles. In the design of such a motor, thermal analysis is necessary to maximize the power density because the loss is proportional to the power of a motor. Therefore, a cooling device as a heat sink is required internally. Generally, a cooling system designed with a water jacket structure is widely used for electric motors because it has advantages of simple structure and cooling effectiveness. An effective approach to analyze an electric machine with a water jacket is a thermal equivalent network. This network is composed of thermal resistance, a heat source, and thermal capacitance that consider the conduction, convection, and radiation. In particular, modeling of the cooling channel in a network is challenging owing to the flow of the coolant. In this paper, temperature prediction using a thermal equivalent network is performed in an ISG that has a water cooled system. Then, an experiment is conducted to verify the thermal equivalent network.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.443-449
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• 2014

Although risk reduction of construction projects have been continued, the risk of fatal accident has been increased. The purpose of this paper is to reduce the cause of the essential risk factors. Questionnaire survey of construction companies in domestic was conducted and the Multiple Regression Analysis of statistics program was used to grasp effective factors among the risk factors of construction companies in domestic. Development of the essential risk factors and its application to projects could lead to improvements such as compression of network, reduction of cost, improvement of quality and reduction of safety accident.