• 디지털융복합연구
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• 제16권5호
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• pp.55-63
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• 2018

중국 물류 산업에 큰 변화가 있었음에도 중국 물류의 연구 동향에 대한 연구는 거의 이루어지지 않았다. 기존 연구는 운송 효율성, 창고 위치 및 항만 효율 등과 같은 세분화된 주제로 연구가 진행되었다. 본 연구에서는 2000년부터 2017년까지 중국 물류의 연구 동향을 SNA방법을 이용하여 분석하였다. 자료는 해외저널에서 수집되었으며, 총 82 개 관련 학술지가 분석대상으로 사용되었다. 2000년에서 2017년까지 기간을 나누어 분석을 진행하였고, 첫 번째 기간 (2000-2008)은 "Globalization", "Hong Kong", "FDI" 및 "outsousing"과 같은 키워드가 상위 키워드로 도출되었다. 두 번째 기간(2009-2013)의 결과는 "internation trade", 및 "reverse logistics"와 같은 키워드들이 도출되었고, 세 번째 기간(2013-2017)에는 "3PL", "warehousing", "railways", "supply chain", "economic", "port" 및 "Belt and Road"등의 키워드가 상위로 나타났다. SNA 방법을 사용한 중국물류 연구 트렌드 분석 결과, 세계화 상황에서 중국이 급속히 변화함에 따라 중국 물류의 연구동향이 진화하고 있음을 보여주고 있다.

• 전력전자학회논문지
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• 제21권5호
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• pp.381-387
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• 2016

Many efforts have focused on the improvement of power density and efficiency by downsizing the motor and inverter. Recently, Toyota, Honda, and GM realized that the compact-sized motor uses the hairpin structure with increased space factor. Reducing the maximum torque from high-speed technique also makes it possible to design the high-power density model. Toyota and Honda used the newly developed power semiconductor IGBT to decrease conduction loss for high-efficiency inverter. In particular, Toyota used the boost converter to increase the DC link voltage for high efficiency in low-torque high-speed region. Toyota and GM also used the double-sided cooling structure for miniaturization of inverter for high-power density.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.44-46
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• 2003

Nowaday it is trend to be one cooling radiator and cooling fan from separate engine radiator and air condition radiator in cars. For the cooling fan is developed a electrical motor which is limited in size. The motor should be working in silence and have no electromagnetic Problem and high efficiency. In this paper will be proposed some parameters for improvement of the efficiency of a BLDC motor which is developed for the cooling system after theoretical and experimental investigation.

• 설비공학논문집
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• 제13권7호
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• pp.564-571
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• 2001

The present study investigated the effect of key parameters on the performance of a cascade system using R-22 and R-23 refrigerants. Experimental data for the cascade system have been compared with simulation results using thermodynamic analysis. The cascade system tested at the evaporating temperature of $-80^{\circ}C $ and the condensing temperature of$40^{\circ}C $. The key experimental parameters were the evaporating temperature of the HTC(-35, -30, -25, -20, $-15^{\circ}C $) and mass flux of the HTC(200, 250, 300kg/$m^2$s). As the evaporating temperature and the mass flux of the HTC were increased respectively, the COP and the refrigerating efficiency were increased and then decreased while the volume flow rate per unit refrigeration capacity showed the opposite trend. The maximum COP and refrigerating efficiency were obtained at the evaporating temperature of the HTC of $-25^{\circ}C $ and the mass flux of 250 kg/$m^2$s.

• 열병합발전
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• 통권36호
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• pp.16-21
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advance steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advance in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2174-2179
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advanced steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advances in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• 한국환경과학회지
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• 제23권1호
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• pp.105-112
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• 2014

With the incorporation of hydrogen peroxide($H_2O_2$) and NaLS as an initiator and emulsifier, acrylic acid monomer was graft copolymerized with sodium alginate prepared from alginic acid, and then the grafted copolymer was confirmed through IR spectrometer. When the amounts of acrylic acid increased the grafting also showed increasing trend. While the contents of hydrogen peroxide was varied in the aqueous sodium alginate solution, the grafting efficiency decreased gradually as the amounts of initiator increased.

• 플랜트 저널
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• 제5권4호
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• pp.73-79
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• 2009

Increase of consumption in limited coal reserves leads prices surging. As a result, iron works which produce products with coal are in difficulties. Accordingly, it is required a lot of research of using non-caking coal that is relatively low cost and has abundant reserves. Direct drying and indirect drying are two major methods of drying the coal. Recently, to minimize the needed calories and to save energy, using fluidbed or fluidizing method is a recent main trend of minimizing the size of the facility and maximizing energy efficiency. However there is also disadvantage such as increasing facility investment because of installing additional facilities in the latter part. In this study, we will have theoretical researches on the indirect drying method with heat exchange system which have been traditionally used. As a result it is expected to increase the efficiency of the facility operation.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.1009-1016
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• 2022

As environmental concerns grow, people are becoming more aware of energy efficiency, carbon reduction, and sustainable development. Leadership in Energy and Environmental Design (LEED) certification is currently the most widely recognized building environment assessment method connected to energy and the environment worldwide. This study explores trends for six factors (energy and atmosphere, materials and resources, indoor environmental quality, sustainable sites, water efficiency, and innovation in design) to assess four levels of LEED certification (Platinum, gold, silver, and certified) using 11,209 LEED projects in the United States. The study analyzes trends using scores of percentages of maximum points by certification level, ownership type, space type, and climate zones. With the interest in the Environmental, Social, and Governance (ESG) principle on the rise, this study contributes to a better understanding of the trends and future of LEED certification in the built environment sector.

• 한국프랜차이즈경영연구
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• 제3권1호
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• pp.130-143
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• 2012

Franchise store retailing is taking on ever greater roles in business and commerce in China. The diverse product range, small-batch order, high frequency and time-specific requirements inherent in retail logistics make it the most complicated of all categories of logistics. In franchise store retailing, expanding business scales make trans-regional development a trend. Without a well-functioning logistic system, the standardized delivery of products would be held back, impacting trans-regional development strategy and operational costs. Therefore, the efficiency of franchise store retailing largely depends on logistical efficiency. The integrated and streamlined management of franchise stores depends in large measure on their logistical centers. As such, logistical centers constitute the key link and bears on core competitiveness in franchise store retailing. This thesis begins with an analysis of the current developments and four basic logistical models of franchise store retailing in China, proceeds to summarize developmental trends as well as focal issues and proposes an efficiency enhancing plan.