• Hwankyungkyoyuk
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• v.3 no.1
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• pp.125-129
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• 1992

The purpose of this study was to investigate the condition of school water supply systems and to provide a way to supply safe and sanitary water in schools. In 1991 present, 56.9% of schools in the whole nation are provided with water supply system. And in urban schools, the percentage of small water supply system was larger than that in city. In the survey on water quality of supply water in Seoul city, the items violating the water quality standard were total bacteria, Zinc and Manganse. For supply the safe drinking water changing the old water mains and executing periodical water quality surveys are needed in addition regulations on school supply water and sanitation are also necessary to the drinking water management in schools.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.41-49
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• 2007

More diversified and strengthened safety regulations require higher safety vehicle with less weight. The structural foam can play a role for restraining section distortion of main body members undergoing bending collapse at vehicle crash. In this study, using structural foam modeling technology, validated in previous work, the bending collapse characteristics were evaluated for two types of circular and actual vehicle body frame sections. With changing the foam filling method, outer panel thickness and section shape, load carrying capability and absorbed energy were observed. The results indicate valuable design strategy for effectively elevating bending collapse performance of body members with foam filled.

• Journal of Aerospace System Engineering
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• v.10 no.2
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• pp.7-13
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• 2016

Multi disciplinary approach for aerodynamics, structure, propulsion, and flight control system is necessary to develop High Altitude Long Endurance Unmanned Aerial Vehicles (HALE UAV). Various HALE UAV development trends are surveyed to understand their operational requirements. Separating the UAV Take Off Weight by 150kg, Airworthiness implementation direction for HALE UAV is studied under the current Airworthiness regulations. NATO STANAG 4671 and STANAG 4703 Airworthiness certification criteria are analyzed, and their applicability was proposed for future HALE UAV development. In addition, minimization of the risk for UAV is studied by considering probability of cumulative catastrophic failure for HALE UAV. This Hazard Risk Index can support the future UAV Airworthiness Certification Criteria.

• Agribusiness and Information Management
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• v.5 no.2
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• pp.7-15
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• 2013

As the consumers' anxiety for food increases, the interest in food safety also increases. To satisfy the public requirement on food safety, the government is trying to set up a food safety standard by using regulations and certification systems. However, there is still difficulty in building up complex traceability systems for medicinal crops including ginseng due to the low participation of farming industries. The purpose of this empirical research is to draw factors that impede the GAP adoption of ginseng farms. By comparing the average attitude and intention to adopt the ginseng farms' depending on its characteristics through a two-tailed test, it was drawn that continuous farming education can positively influence the GAP adoption of the ginseng farms.

• Air Cleaning Technology
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• v.23 no.3
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• pp.1-9
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• 2010

This study proposed the optimum design values for the biological clean room system observing the regulations of Hazard Analysis Critical Control Point (HACCP). Even though the standard for industrial clean room system has been well established, the basis for biological food clean room system is the first stage. In order to prevent the contaminations in advance for food storages, processes, and distributions, the criterion of Hazard Analysis Critical Control Point is positively required. This study also suggested the possible ways of how to avoid the hazardous contaminations.

• Korean Management Science Review
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• v.32 no.3
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• pp.37-54
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• 2015

This paper suggests energy efficiency which can be the foundation on corporate profit and effective energy management following by change of global climate and of energy-related regulations. Using comparable financial information and information related to energy use, an DEA (Data Envelopment Analysis) model has been used to identify energy efficiency with DMU (Decision Making Unit)s which are companies subjected to reduce greenhouse gas emission in 2009. Through this research, different from existing researches, environmental variables which can influence on energy efficiency are identified. The results show as follows. First, most of companies follow IRS, which means scale of economy exists among units so that they have more opportunity to increase efficiency by increasing scale of inputs. Second, this research identified that depending on the difference of environmental characters such as the emission structure and the size of companies, energy efficiency of the companies turns out differently.

• Plant Journal
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• v.8 no.2
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• pp.70-81
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• 2012

The study aims to supplement facility management plan and safety regulations & standard of oil pipeline by searching and reviewing related regulation & standard inside and outside of the country. Korean regulation & standard is reviewed based on harbor and fishery design standard of the ministry of maritime affairs and fisheries, general technology standard of oil pipeline safety regulation, gas excavation construction and safety maintenance indicator of Korea gas corporation. Global regulation & standard is reviewed based on U.S standard inspection for offshore pipeline and Europe/Mexico standard inspection for offshore pipeline. The contents of offshore pipeline installation is inserted into pipeline sector for objected facilities of safety inspection regulation & standard and, the standard of safety inspection for offshore pipeline is newly presented into pipeline maintenance part of the planning facilities management with its inspection period and method.

• Journal of Power Electronics
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• v.16 no.6
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• pp.2057-2066
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• 2016

An extension of the one-cycle control (OCC) method for switched-capacitor (SC) converters is proposed in this paper, featuring a fast dynamic response, wide line and load operation ranges, and simplicity in implementation. To illustrate the operation principle of this nonlinear control method and to demonstrate its simplicity in design, a dual-phase unity gain SC converter is examined. A new control loop based on the charge balance in a flying capacitor is formulated for the OCC technique and implemented with a 15W dual-phase unity gain SC converter on a circuit board for control verification. The obtained experimental results show that external disturbances can be rejected in one switching cycle by the OCC controlled SC converter with good line and load regulations. When compared to other control methods, the proposed nonlinear control loop exhibits superior dynamic performance in suppressing input and load disturbances.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.173-174
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• 2015

본 논문에서는 가변 스위칭 주파수를 이용하여 단일스위치 이중출력 플라이백 컨버터의 전압조정특성을 향상시키는 방법을 제안한다. 기존의 이중 출력 컨버터에서는 부하의 변화, 누설 인덕턴스나 자화 인덕턴스의 영향 때문에 두 개의 출력전압을 개별적으로 제어하기가 힘들다. 제안된 방법에서는 컨버터의 2차측에 조정된 필터를 추가함으로써, 스위칭 소자의 듀티비가 일정하더라도 스위칭주파수에 따라 다른 전압을 출력하도록 하였다. 따라서 듀티비 제어뿐 아니라 스위칭 주파수 제어로도 출력전압을 제어할 수 있기 때문에 어떠한 상황에서도 각각의 출력을 제어하는 것이 가능하다. 추가적인 능동소자 없이 필터만을 추가 하여 기존 플라이백 컨버터의 특징인 간결한 제어알고리즘과 회로구성을 유지하였다. 또한 프로토 타입의 이중출력 컨버터를 이용하여 제안된 방법의 성능 및 구현 가능성을 검증하였다.

• Molecules and Cells
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• v.41 no.12
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• pp.1000-1007
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• 2018

Mitochondria and endoplasmic reticulum (ER) are essential organelles in eukaryotic cells, which play key roles in various biological pathways. Mitochondria are responsible for ATP production, maintenance of $Ca^{2+}$ homeostasis and regulation of apoptosis, while ER is involved in protein folding, lipid metabolism as well as $Ca^{2+}$ homeostasis. These organelles have their own functions, but they also communicate via mitochondrial-associated ER membrane (MAM) to provide another level of regulations in energy production, lipid process, $Ca^{2+}$ buffering, and apoptosis. Hence, defects in MAM alter cell survival and death. Here, we review components forming the molecular junctions of MAM and how MAM regulates cellular functions. Furthermore, we discuss the effects of impaired ER-mitochondrial communication in various neurodegenerative diseases.