• 전력전자학회논문지
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• 제17권5호
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• pp.431-437
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• 2012

PV simulators are essential equipment for testing power conditioning systems (PCS) which are one of an important part in PV generator systems, for testing before shipment. High dynamic PV simulator is required since MPPT(Maximum Power Point Tracking) test procedure has been established by EN50530 regulation recently. Most high quality PV simulator prevailed in the market is linear type which however has low efficiency. This paper proposes design guide lines for the power stage and LCL type filter cooperating with a switching mode PV simulator that shows high efficiency and very low power consumption. Proposed theory is verified by experiment.

• 유공압시스템학회논문집
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• 제6권3호
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• pp.23-31
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• 2009

Counter shaft transmission is a popular automatic transmission power train in construction vehicles such as wheel loader and forklift. The gear train layout of counter shaft transmission is a very basic and important development stage because it affects the most of components design including hydraulic system and shift control algorithm, etc. This paper presents a design methodology for the gear train layout from the analysis of power flow path and clutch hook-up of the existing counter shaft transmission that is adopted in commercialized construction vehicles. Also, independent constraints for the meshed gear ratios are derived in order to realize forward 4-speed and reverse 3-speed gear ratio. The layout design principle proposed here was applied to the new original counter shaft transmission that is underdevelopment.

• 한국철도학회논문집
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• 제7권1호
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• pp.1-8
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• 2004

A newly-built inverter has to undergo a series of stress tests in the final stage of production line. This can be achieved by connecting it to a dynamometer consisting of a three-phase machine joined by a rigid shaft to a DC load machine. The latter is controlled to create some specific load characteristic needed for the test. In this paper a test method is proposed, in which no mechanical equipment is needed. The suggested test stand consists only of a inverter to be tested and a simulator converter. Both devices are connected back-to-back on the AC-side via smoothing reactors. The simulator operates in real-time as an equivalent load circuit, so that the device under test will only notice the behaviour of a three-phase machine under consideration of the load. In oder to prove rightness of the suggested test method, the simulation and actural experiment carried out emulation for a 2.2kW induction motor.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.512-518
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• 2006

Economize the energy, further study is highly needed at the very beginning stage of the building plan. To fulfill this study, research of the buildings in Busan will be carried out, and find out the relations between pure load of buildings and capacity of heat & cooling equipment. Therefore this study is suggesting better idea of calculating capacity from having a thorough grasp of the problem with comparing and analyzing of extra-factor.

• 한국건축친환경설비학회 논문집
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• 제12권6호
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• pp.606-617
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• 2018

Increased density of racks has resulted in increased use of data center cooling energy and the needs for energy efficient cooling systems has increased. In response to these needs, ASHRAE presented a performance indicator, which is Mechanical Load Component (MLC), for the purpose of evaluating systems at the design stage. However, the MLC metrics presented in the current standard can only be determined for system compliance and compared alternative systems with the system configuration completed. Therefore, there are limitations to considering MLC from the early stages of design. In this study, to extend the scope of application of MLC in the design phase, the design factors of the main equipment comprising the cooling system are classified by the MLC load component and interrelations between design factors were identified.

• 드라이브 ㆍ 컨트롤
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• 제19권4호
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• pp.85-90
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• 2022

In this paper, a DC converter to improve the performance of Power LED system is discussed. The mathematical model of PWM converter power stage using 3-Terminal PWM cell is introduced for power LED system. A controller for DC converter system is used as a self-tunning regulator with a recursive least-squares algorithm. Minimum variance control method is used as a control law. Experiment results verified that proposed control system could improve the performance of Power LED system.

• Advances in aircraft and spacecraft science
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• 제9권3호
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• pp.243-261
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• 2022

Broad writing on the examination of sandwich structures mirrors the significance of incorporating thermal loadings during their investigation stage. In the current work, an endeavor has been made to concentrate on sandwich FGM beams' bending behaving under thermal loadings utilizing shear deformation theory. Temperature-dependent material properties are used during the analysis. The formulation includes the transverse displacement field, which helps better predict the behavior of thick FGM beams. Three-different thermal profiles across the thickness of the beam are assumed during the analysis. The study has been carried out on both symmetric and unsymmetric sandwich FGM beams. It has been observed that the bending behavior of sandwich FGM beams is impacted by the temperature profile to which it is subjected. Power-law exponent and thickness of core also affect the behavior of the beam.

• 한국생활환경학회지
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• 제18권3호
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• pp.330-337
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• 2011

This research quantified(/m²) the supplied materials at the construction stage of apartments, the main architecture form domestically, and presented the average CO₂ emission by analyzing 50 apartment complexes. The results are as follows. CO₂ emission of each type of constructions by supplied materials is architecture (78.8%), machine (8.8%), electricity (5.3%), civil engineering (3.4%), landscaping (3.4%), and communication (1.0%). The building construction charged about 79%. Average CO₂ emission of total 50 apartment complexes according to supplied material expense appeared to be 950 kg-CO₂/m², and when core-type pillar was included CO₂ emission largely increased.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.653-658
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• 2011

Construction works of civil infrastructure projects generate a considerable amount of carbon emissions by utilizing a set of energy-intensive equipment and causing traffic congestion. However, the voluntary efforts of the contractor to mitigate these emissions are at an early stage. To address this issue, this paper explores the opportunities to take carbon emissions that would be caused from construction works into consideration in contracting methods and procedures. The opportunities for reducing carbon emissions from construction activities themselves are examined under the framework of Performance Contracting for Construction (PCfC), and carbon emissions from traffic congestion are attempted to be incorporated into the Road User Cost (RUC) calculation. This paper also identifies and discusses major challenges that must be confronted when considering the mitigation of these emissions in contracting methods and procedures.

• 시큐리티연구
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• 제14호
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• pp.311-336
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• 2007

본 연구는 생물테러리즘의 발생시 이에 대응하는 개념과 선진국들의 생물테러리즘의 대응태세를 알아본 후 한국의 대응태세를 알아보는 연구이다. 생물테러리즘의 발생에 대응하는 태세는 사건의 발생 흐름에 따라 탐지단계, 보호단계, 진단단계, 제독 및 해독단계로 구분해 볼 수 있다. 탐지단계는 한국은 접촉식으로 개발하고 있으나, 선진국에서는 원거리에서 탐지할 수 있는 장비를 개발하고 있다. 한국도 원거리에서 탐지할 수 있는 체계를 개발해야 할 것이다. 접촉식 장비도 민삼하게 작동할 수 있는 장비로 발전 되어야 한다. 보호장비중 한국의 방독면은 세계적으로 그 품질이 우수하나, 기타 피복류 등에 대해서는 첨단 과학기술을 적용할 수 있도록 개선되어야 한다. 진단 장비도 초동조치팀이 현장에 출동해서 즉시 판단할 수 있도록 하는 장비로 개발되어야 한다. 제독을 위한 물자는 인체에 무해하고, 장비에도 무리를 주지 않는 새로운 물질로 개선되는 추세로서 한국에도 이러한 물자가 확보되어야 한다. 해독을 위한 기술은 백신 및 항생제를 개발하는 것으로서 전 세계적으로 노력을 공유하여 개발할 필요가 있으며, 이를 위해 한국의 의료기술을 더욱 발전시킬 필요가 있다. 이외에도 대응매뉴얼, 훈련 모델, 공보 노력, 트라우마 증후군 대비 등의 노력을 기울여야 할 것이다.