• Transactions on Electrical and Electronic Materials
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• v.16 no.3
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• pp.124-129
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• 2015

Organic electronics are the domain in which the components and circuits are made of organic materials. This new electronics help to realize electronic and optoelectronic devices on flexible substrates. In recent years, organic materials have replaced conventional semiconductors in many electronic components such as, organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs) and organic photovoltaic (OPVs). It is well known that organic light emitting diodes (OLEDs) have many advantages in comparison with inorganic light-emitting diodes LEDs. These advantages include the low price of manufacturing, large area of electroluminescent display, uniform emission and lower the requirement for power. The aim of this paper is to model polymer LEDs and OLEDs made with small molecules for studying the electrical and optical characteristics. The purpose of this modeling process is, to obtain information about the running of OLEDs, as well as, the injection and charge transport mechanisms. The first simulation structure used in this paper is a mono layer device; typically consisting of the poly (2-methoxy-5(2'-ethyl) hexoxy-phenylenevinylene) (MEH-PPV) polymer sandwiched between an anode with a high work function, usually an indium tin oxide (ITO) substrate, and a cathode with a relatively low work function, such as Al. Electrons will then be injected from the cathode and recombine with electron holes injected from the anode, emitting light. In the second structure, we replaced MEH-PPV by tris (8-hydroxyquinolinato) aluminum (Alq₃). This simulation uses, the Poole-Frenkel -like mobility model and the Langevin bimolecular recombination model as the transport and recombination mechanism. These models are enabled in ATLAS- SILVACO. To optimize OLED performance, we propose to change some parameters in this device, such as doping concentration, thickness and electrode materials.

• Journal of the Korea Institute of Building Construction
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• v.10 no.1
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• pp.175-180
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• 2010

Despite continuous efforts by the construction industry to achieve better quality, it doesn't seem that much has been improved. This is mainly because current specifications do not satisfy a change in the market environment, which is that a higher level of quality is now demanded by users. Quality improvement efforts have been satisfied merely to meet specifications. On the other hand, advanced countries have been experienced great success in their construction techniques and have reduced costs by introducing apay adjustment system to the construction industry, in which compensation is based on performance. Following their example, Koreashould introduce such a pay adjustment system in order to motivate the members of our construction industry to achieve better quality and a higher level of construction techniques. However, there has been a lack of a rational approach to the development of a system for cost coordination, as well as performance and quality inspection. Thus, in this study a legal and logical plan was developed that can be used to adjust the construction cost, along with the performance inspection of quality results, in order to introduce a pay adjustment system that is appropriate for domestic regulations.

• Korean Journal of Construction Engineering and Management
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• v.19 no.1
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• pp.90-102
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• 2018

In preparation of the increase in the domestic debts and the rise in the US interest rate, the Korean government has started to strengthen the regulation on the property market since 2017. So, it is likely that the sales in the domestic construction market would be decreased. Even in the overseas plant projects market, as there has been the continuous increase in the cost and the resulting increase in the losses, it looks hard for the large construction companies to keep their credit ratings as they are now. This study is designed to check Korean government's property policy and any possible problems caused by the overseas and domestic economic environment, which include the property market policy, interest rate, rise in the property price and lackluster sales in housing market. It showed the change in the credit ratings by finding out the sales, work capability, sales in non-governmental projects, operating profits and PF contingency liabilities. For this study, the questionnaires were sent to 30 practical experts to analyze the effect of the risk factor on the outside credit rating of large construction companies.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.399-404
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• 2015

The cost of fuel in ships has recently increased due to a rapid increase in international oil prices and international restrictions regarding the greenhouse effect generated from the burning of fuel. Therefore, different methods for changing the hull designs for improving energy efficiency, developing coating for reducing friction resistances, developing additives for improving engine thermal efficiency, and low-speed operation for reducing fuel consumption have been considered. The developments of high-speed, large-scale, and energy-saving vessels are deemed essential to adapt to the recent high oil price era. Therefore, it is important to analyze Precisely the qualitative and quantitative changes in the resistance value of the local areas of the hull surface. In this study, the engine performance before and after docking was analyzed to examine friction resistance caused by marine growth on the hull as a basic study for improving the energy efficiency. The result was then presented by comparing it with the previous data for 2.5 years between docks to investigate the performance of the main engine, the change in friction resistances and loads, the fuel consumption and ship speed.

• Journal of Adhesion and Interface
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• v.11 no.2
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• pp.76-83
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• 2010

The extensive use of fossil resources over the past century resulted in dwindling supply and surging price of oil and it is strongly suspected that irreversible global climate change might be due to carbon dioxide emitted from combustion of fossil carbons. With this regard, much attention is recently paid to renewable and sustainable resources as alternatives to petroleum. In this review, we considered a range of efforts to replace petroleum-derived chemicals, particularly adhesive materials with renewable and sustainable plant-based biomass feedstock.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.270-287
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• 2015

According to the increase of the operating cost and material cost of a ship due to the change of international oil price, a demand for the lightening of the ship weight is being made from various parties such as shipping companies, ship owners, and shipyards. To satisfy such demand, many studies for a light ship are being made. As one of them, an optimal design method of an existing hull structure, that is, a method for lightening the ship weight based on the optimization technique was proposed in this study. For this, we selected a hatch cover of a bulk carrier as an optimization target and formulated an optimization problem in order to determine optimal principal dimensions of the hatch cover for lightening the bulk carrier. Some dimensions representing the shape of the hatch cover were selected as design variables and some design considerations related to the maximum stress, maximum deflection, and geometry of the hatch cover were selected as constraints. In addition, the minimization of the weight of the hatch cover was selected as an objective function. To solve this optimization problem, we developed an optimization program based on the Sequential Quadratic Programming (SQP) using C++ programming language. To evaluate the applicability of the developed program, it was applied to a problem for finding optimal principal dimensions of the hatch cover of a deadweight 180,000 ton bulk carrier. The result shows that the developed program can decrease the hatch cover's weight by about 8.5%. Thus, this study will be able to contribute to make energy saving and environment-friendly ship in shipyard.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.199-209
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• 2013

This study empirically investigates how the switching barriers influence the consumer's perceived intention to change his or her current favorite internet shopping mall. Drawing from switching cost theory, variables pertaining to trust, shopping mall service quality, product price, web page quality, switching barriers were examined to examine the consumer's behavioral intention to switch to another shopping mall. The interaction effect of consumer involvement was also included in the research model. The results of the study report that customer satisfaction and switching cost influence shopping switching intention, while the effect of attractiveness of the shopping mall was not significant in the statistical analysis. Furthermore, a moderating effect of consumer involvement was not found significant in the PLS analysis. The study demonstrates the shopping mall owners try to increase the customer's overall satisfaction and raise the switching barrier by providing mileage advantages, for instance.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.41-53
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• 2017

This study focuses on the current state of Smart Grid policy in Japan and its problems while the interest in Smart Grid has been increasing since the March 2011 earthquake in East Japan. As a result of the analysis, Japan introduced the fixed price buying system of new and renewable energy in response to the power supply and demand problem caused by the 2011 earthquake in East Japan, and established a decentralized green electricity trading market in which electricity generated from new and renewable energy is traded Smart Grid-related projects were implemented as a solution to solve energy crisis and environmental problems at the same time. As a result, we achieved visible results such as suppressing peak power, reducing CO2 emissions, and securing stable supply and demand of energy using renewable energy sources. On the other hand, the improvement of current Smart Grid policy operation in Japan and the introduction of stabilization system of power system, promotion of international standards of domestic technology related to smart grid, and support for strengthening security of smart grid.

• Culinary science and hospitality research
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• v.7 no.2
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• pp.157-179
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• 2001

Today the number or Chinese tourist visiting Korea is expected by 60% more than the number of them in the last year trunks to Chinese government's new policy on opening international trip. Overriding the striking perception of the new Chinese tourism market, the pre-research on this matter is not remarkable so far. It is expected that the theoretical base on the subject should be concrete. the purpose of the article is to provide the out-and-out information including the chinese market, the change of circumstance in China. Futhermore the study is proposed to offer valuable factor evaluating Chinese tourist to choose Korean restaurant and the relational consideration of the menu between estimation and satisfaction at the restaurant during their stay in Korea. In order to achieve the purpose of this paper, it is gore ahead of the literature review including the previous research on the menu of Hotel & Restaurant The major field research is to build a frame of the paper and present the model to release my humble theory. The 1imitation of the study was to make much of the literature basis due to insufficient previous research on the issue, The study would be framed into 6parts 1ike introduction, literature review, analysis of present coalition in China, major study including exploitative research, suggestion and dissuasions & conclusion. After the exploitative research, the study was approached to make findings through the questionnaires designed to find the relationship factor between chinese tourist's evaluation and satisfaction in the Hotel and Restaurant. According to the finding, chinese tourist tend to prefer the group ranging resonable-price and Japanese dishes to other group. They also interested the certain recipe including fish and vegetable. The evaluation menu is directly related to the satisfaction of Chinese tourist and we need a substantial managerial insight on it when the menu is already designed.

• The Research Journal of the Costume Culture
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• v.18 no.4
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• pp.626-639
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• 2010

The club culture is not something unified. Rather, it is a group of subcultures which share intertwined areas. And it keeps its own dress code, dance style, music genre along with series of authoritarian and unlawful rituals. For young adults, a club is a new cultural space to enjoy in reasonable price and they can express themselves without thinking much about others. A club creates its unique mass culture by producing continuously changing and experimental fashion styles. As the club culture’s influence becomes powerful, the club market was established and experimental fashion styles are wide spread among general public, young adults who try to express their unique characters and even fashion-leading industry. The study results are as follows. First, dance club and its derivative, rave is symbolic axles and the center of social activity. They are also defined as culture which is related to specific space that continues to present and change sound and style. Second, the definition of clubber in a dictionary is club member or a person who is united with others. Third, based upon clubbers' fashion styles in Hongdae and Kang-nam areas, there are 5 different images including sexy casual, lingerie, dynamic, chic style and feminine style. Fourth, based upon case study above, to take unique life style of fashionista that leads fashion with trendy fashion style into account, we suggested five designs which are unique, sensitive and trendy. Fifth, through analyzing clubber generation and design factors of clubbers' fashion style combined with various trend, unique brand was developed to meet the demands of clubbers who want differentiated images and leading styles.