• Journal of Digital Convergence
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• v.14 no.12
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• pp.121-131
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• 2016

This research aims to analyze domestic articles related to entrepreneurship and elicit implications for future research. To this end, bibliometric analysis was conducted for the authors and titles of 1,887 articles published in the Korean Citation Index between 1997 and 2016. First, in the author analysis, Dae Yong Chung, Bong Sik Bin & Jeong Ki Park, and Sung Sik Bahn were noticeable in terms of the number of articles, the number of citation and the formation of the researchers' network. Second, in the title analysis, the characteristics of entrepreneurs and education in entrepreneurship, entrepreneurial strategies and case studies, the empirical analyses regarding entrepreneurial performance, investment in startups, and Korean IT companies were found to be the most active research fields. The results of this study can be used in selecting co-researchers and exploring research areas in the future.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.45-55
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• 2013

Recently, with achieved US$ 500 Billion international cumulative construction order, the Korean government presented overseas construction industry visions for international orders of US$ 100 B and entering the top five countries in global construction market. Also, Korean companies are developing strategies for expansion of international markets especially focused on company competitiveness as a target market. Therefore, this study aims to analysis of competitiveness for the Cambodian building construction market, which presents abundant development potential. The results of IPA result were as follows; construction order information and supply chain management are needed for public tender projects and F/S, global project financing, and supplier relationship management are needed for construction investment projects. However, this work is still considered to provide the basic data that can help Korean construction companies who plan to enter the Cambodian building construction market strengthen their medium and long-term capabilities.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.294-301
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• 2018

In winter, thermal screens are widely used to reduce heat loss from greenhouse to save energy. Unfortunately, not much data are available to the farmer to compare thermal screens while selecting the one that meets their specific requirements. Thus, there is a need to investigate the thermal performance of thermal screens. To address this issue, the Building Energy Simulation (BES) model of a hot box was used to calculate the overall heat transfer coefficient (U-value) of the thermal screens. To validate the model, computed and experimental U-values of single-and double-layered polyethylene (PE) material were compared. This validated model was used to predict the U-values of the selected thermal screens under defined weather conditions. We quantified the U-values of each selected material and significant changes in their U-values were noted in response to different weather conditions. Notably, the thermal properties of the tested screens were taken from the previous literature to calculate U-values using the BES model. The U-values of the thermal screens can help researchers and farmers evaluate their screens and make pre-design decisions that suit their investment capabilities.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.11
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• pp.1161-1167
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• 2015

A slender guideway is essential in improving aesthetically and reducing its construction cost which accounts for about 70% of overall investment for maglev system. As the slender guideway, however, may increase its deformation, its effect on levitation stability and guidance performance needs to be analyzed. The purpose of this study is to analyze the effect on guidance characteristics of maglev due to the lateral deformation of the guideway girder and lateral irregularity of guiderail. For doing this, 3D model considering lateral deformation of girder and irregularity of rail of the guideway is developed. Using the dynamic interaction model integrated with the proposed guideway and maglev vehicle including electromagnetics and its controller, guidance characteristics of maglev are analyzed. It is analyzed that the effect on lateral deformation of girder is relatively small compared to deformation on the lateral irregularities of guiderail.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.233-238
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• 2018

SMEs and small enterprises are making various attempts to manage SMEs in terms of equipment, safety and energy management as well as production management. However, SMEs do not have the investment capacity and it is not easy to build a smart factory to improve management and productivity of SMEs. In this paper, we propose a smart factory construction algorithm that partially integrates the factory equipment currently operated by SMEs. The proposed algorithm supports collection, storage, management and processing of product information and release information through IoT device during the whole manufacturing process so that SMEs' smart factory environment can be constructed and operated in stages. In addition, the proposed algorithm is characterized in that central server manages authentication information between devices to automate the linkage between IoT devices regardless of the number of IoT devices. As a result of the performance evaluation, the proposed algorithm obtained 13.7% improvement in the factory process and efficiency before building the Smart Factory environment, and 19.8% improvement in the processing time in the factory. Also, the cost of input of manpower into process process was reduced by 37.1%.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.95-102
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• 2011

The purpose of study is to estimate heating, cooling load performance and economic efficiency in office building with applied the functional paint. this paint can reduced SHGC(Solar Heat Gain Coefficient) on the glazing surface by coating. In this study, estimated to compared with double glazing, low-e glazing, IP(Insulation Paint) and IPu(Insulation UV-Cut Paint) coating glazing. As a result of this study, 1)heating & cooling load Analysis, SHGC value and U-factor of double glazing is about 0.70 and 3.29($W/m^2K$). low-E glazing is about 0.65 and 2.70($W/m^2K$). Two-side it is about 0.27 and 3.25($W/m^2K$). When compared to double glazing, annual heating & cooling load of low-E glazing, Two-side IPu and IP paint coating glazing is 3,012MWh($124kWh/m^2$), 2,910MWh($120kWh/m^2$), 2,867MWh($118.4kWh/m^2$) and 2,867MWh($118.4kWh/m^2$). It i sreduced to 2.0%, 5.2%, 6.7%, and 6.7% respectively. 2)the estimation of economic efficiency, low-e glazing installed in office building can not recover the investment within a lifetime 40years. but IPu and IP paint, two-side coating in glazing, have a payback period of 13 years respectively.

• Plant Journal
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• v.14 no.3
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• pp.42-48
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• 2018

If the combined operation of Gwanggyo Cogeneration plant is similar to that of 2017, the CHP return temperature is lowered to $4^{\circ}C$, $6.3^{\circ}C$ and $7.8^{\circ}C$ according to the increase of heat surface area and the electric power is increased by 413 kW and 676 kW from its original 39,025 kW, and when the heat surface area is increased 75% electric power increases by 834 kW, totaling 39,859 kW. NPV, which is an economic analysis standard, is worth 350 million won, 500 million won, and 520 million won, and all measures to increase the heat surface area are proven to be worth the investment. As the heat transfer area increased, the electric power and NPV increased proportionally but the rise amount decreased. The electrical output and NPV were found to be the highest among the three options when the heat transfer area was increased by 75%.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.394-399
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• 2009

Since some decades ago, there has been a concern for resource depletion and environmental pollution associated with building properties. In addressing such impact of the built environment, there is a recognition of the existence of alternative building materials, fuels for energy supply as well as technologies for waste handling and disposal. Nevertheless, for long time, the choice between such alternatives was dictated by factors such as differences in prices and aesthetic values. A new important dimension in discriminating between different options is the environmental dimension. This aspect is important since buildings are one of the spatially big new additions to the natural environment that consume a lot of materials and energy during their long lifetime. Thus, with the environmental dimension kept in mind, a existing cost estimation needs to be changed. A new cost assessment method, Life Cycle Cost, should calculate overall costs with dimensional factors: investment and utility costs as well as maintenance costs over the lifetime of the building. Aiming to give an overview of the present status of Building Life Cycle Assessment(LCA) tools as a basis for further research and development including economic performance, this paper describes and compares 3 different tools for Life Cycle Assessment(LCA) and economic analysis of the green buildings. This paper compared these approaches based on various aspects. These include economic analysis method, evaluation duration, data of results(index). Use of the comparison analysis is to produce a better picture and indicate profits and shortcomings for the tools as a group; thus providing important direction improvement of LCA tool as well as further research and development of this group of tools.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.3
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• pp.386-393
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• 2012

Portfolio selection methods based on stochastic receding horizon approach, which were recently reported in the field of financial engineering, can explicitly consider the dynamic characteristics of wealth evolution and various constraints in the process of performing optimal portfolio selection. In view of the theoretical value, versatility, and effectiveness that receding horizon approach has achieved in many engineering problems, dynamic portfolio selection methods based on stochastic receding horizon optimization technique have the possibility of becoming an important breakthrough. This paper observes through theoretical investigations that the SDP(semi-definite program)-based portfolio selection procedure can be simplified, and has obtained meaningful performance on returns from simulation studies applying the simplified version to Korean financial markets.

• Korean Journal of Construction Engineering and Management
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• v.10 no.6
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• pp.67-77
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• 2009

Infrastructure asset management can be defined as the long term and cost effective management strategy to meet the required service level. In most developed countries, the major motivations of the introduction of asset management are increment in number of assets, extension of maintenance field, accounting approaches of public facilities, performance-based FM(Facility Management), limitations of public funds and public-private partnership, life cycle cost approach, and the development of information technology. This paper discusses the strategic and stepwise methods of introducing infrastructure asset management. Strategic approaches are suggested to develop the practical methods of condition and value assessment of assets, and long-term capital investment plan for optimized decision making(ODM). Required systematic processes are analyzed in terms of resource and technical limitations and detailed implementation plan for each development phases are suggested.