• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.104-111
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• 2006

The non-linear properties of rubber material which are described as strain energy function are important parameter to design and evaluate of rubber spring. These are determined by material tests which are uni-axial tension and bi-axial tension. The computer simulation using the nonlinear element analysis program executed to predict and evaluate the load capacity and stiffness for chevron spring. In order to investigate the heat-aging effects on the rubber material properties, the acceleration test were carried out. Compression set results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot. By using the compression set test, several useful life prediction for rubber material were proposed.

• Journal of Advanced Marine Engineering and Technology
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• 제35권3호
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• pp.301-308
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• 2011

International Maritime Organization (IMO) proposed the Energy Efficiency Operation Indicator (EEOI) in 2005 and the Energy Efficiency Design Index (EEDI) in 2008 so as to address emission concern and regulation. Likewise, Ship Energy Efficiency Management Plan (SEEMP) and Greenhouse Gas (GHG) monitoring and management are also becoming an issue lately. This paper introduces the energy efficiency design index (operation indicator) monitoring system (EDiMS) software can continuously monitor $CO_2$, $NO_x$, $SO_x$, and PM values emitted from ship. The accurate inventory of ships GHG can be obtained from base of emission result during the engine shop test trial and the actual monitoring of shaft power and ship speed. In addition, the ability to store all exhaust emission and engine operation data can be applied as the useful tool of the inventory work of air pollution and ship energy management plan for the mitigation or reduction of ship emissions.

• 수산해양기술연구
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• 제50권1호
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• pp.67-74
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• 2014

Most of steam power plants in Korea are using the method of heating the feed water whenever the ambient temperature around the power plant area below $5^{\circ}C$ to prevent freezing water flowing in the pipe in winter time. But this kind of heat supplying system is not useful to save energy. If we take the method that the temperature of the each pipe is controled by direct measure of temperature by attaching sensor on the outside surface of the feed water tubes, then we can expect that a plenty of energy can be saved. In this study, the computer simulation is used to compare the energy consumption loads of both systems. Energy saving rate is calculated for the location of Incheon area in winter season. Four convection heat transfer coefficients for the ambient air and three initial flowing water temperature inside the tube were used. The result shows that the temperature control system using sensor represents more than 95% of energy saving rate in Incheon area. Even in the severe January weather condition, the energy saving rate is almost 75% in two days basis and even 83% in one day basis.

• 한국지열·수열에너지학회논문집
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• 제12권2호
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• pp.1-6
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• 2016

A ground air heat exchanger (GAHX), also called earth air heat exchanger is a useful technology to be integrated with other renewable energy technologies. In this study, ground-air heat exchanger system for the air source heat pump is introduced. The purpose of this study is to design the volumetric flow rate and the length of GAHX system. A GAHX length model equation has been developed and used for calculation. GAHX thermal efficiency are recommended as 75% and 85% in order to optimize pipe length. $2,750m^3/h$, $2,420m^3/h$ of volumetric flow rate on 88.3m, 111.7m length are suggested for providing 7.5kW thermal capacity. And the number of path is recommended more than two to minimize pressure drop. For future study, advanced model equation study with ground thermal behavior and a more efficient GAHX design will be considered.

• 한국태양에너지학회 논문집
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• 제33권2호
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• pp.64-69
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• 2013

According to the Fourth Assessment Report of Intergovernmental Panel on Climate Change(IPCC) Working Group III, climate change is already in progress around the world, and it is necessary to execute mitigation in order to minimize adverse impacts. This paper suggests future climate change needs, employing IPCC Special Report on Emissions Scenarios(SRES) to predict temperature rises over the next 100 years. This information can be used to develop sustainable architecture applications for energy efficient buildings and renewable energy. Such climate changes could also affected the present supplies of renewable energy sources. This paper discusses one recent Fourth Assessment Report of IPCC (Mitigation of Climate Change) and the Hadley Centre climate simulation of relevant data series for South Korea. Result of this research may improve consistency and reliability of simulation weather data or climate change in order to take advantage of SRES and PRECIS QUMP. It is expected that these calculated test reference years will be useful to the designers of solar energy systems, as well as those who need daily solar radiation data for South Korea. Also, those results may contribute zero carbon and design of sustainable architecture establishing future typical weather data that should be gone ahead to energy efficient building design using renewable energy systems.

• 디지털융복합연구
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• 제9권6호
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• pp.27-37
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• 2011

본 연구에서는 에너지 관리 시스템의 기능 요건을 정립하기 위한 하향식 기능 분석 절차를 제안하고 바람직한 기능 요구사항들을 도출하였다. 하향식 기능 분석을 위해 벤치마킹 대상인 에너지관리 시스템 제품들이 제공하는 공통된 기능들을 추출하고 이들을 기능 그룹 단위로 집합하여 7개의 서브시스템으로 분화하고 각 서브시스템 내에서 제공해야 할 기능들을 분류하여 비교용 템플리트를 만들었다. 벤치마킹은 이 비교용 템플리트에 의거하여 각 상용 제품에서 제공하는 기능들을 분류하여 기능 제공 유무를 기입하는 방법으로 수행되었다. 벤치마킹의 결과로 에너지 관리 시스템이 갖추어야 할 바람직한 기능들을 추출하여 이를 상세하게 설명하였다. 이 연구의 결과는 에너지관리 시스템을 개발하거나 도입하려는 관련자들에게 에너지 관리 시스템이 갖추어야 할 필요 기능에 관한 유용한 정보를 제공한다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제26권1호
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• pp.63-71
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• 2020

Purpose : The purpose of this study is to analyze the elements that affect the energy consumption of general hospitals in Korea. Methods : Factors affecting energy consumption in general hospitals include facility elements and operating elements. The effects of these elements on energy consumption of general hospitals were analyzed by statistical methods such as t-test, anova, correlation analysis, and regression analysis. Results : Total floor area, number of operating rooms, number of MRI, number of staffs, and number of outpatients can be said as useful variables that can explain energy consumption in general hospitals. Implication : It is possible to save energy consumption in general hospitals by adjusting major variables that affect the energy consumption of general hospitals.

• 한국진공학회지
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• 제22권4호
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• pp.198-203
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• 2013

에너지 수확은 우리주변에 존재하는 버려지는 에너지를 유용한 전기에너지로 변환하는 기술이다. 마찰전기 소자는 접촉을 통한 정전기를 유도하는 원리로 동력학적 에너지를 전기에너지로 전환하는 소자이다. 본 연구에서는 소프트 식각 기술을 활용하여 제작 단계를 최소화한 마찰전기 에너지 수확소자를 개발하고, 그 전기적 특성을 측정하였다. 마찰전기를 통한 발전은 마이크로패턴을 통해 마이크로 거칠기를 가진 알루미늄 층과 PDMS 층 사이에서 발생한다. 이때 PDMS 층의 마이크로 패턴은 마스크리스 식각을 통해 만들어진 알루미늄 층의 마이크로 패턴을 소프트 식각법으로 바로 본뜨는 방식으로 제작되었다. 본 소자는 2 V와 20 nA의 발전 성능을 나타낸다.

• 방사선산업학회지
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• 제6권4호
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• pp.289-297
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• 2012

Since Nafion is very expensive and shows the decreased fuel cell performance over $80^{\circ}C$ operating temperature, much work has been carried out in the search for cheaper membrane with high fuel cell performance. Radiation is known to be very useful for the preparation of the polymer electrolyte membranes since it can be effectively used for the introduction of ion conducting functional groups into the commercial film with high mechanical and chemical properties. Here, we summarize the our recent progress in the development of fuel cell membranes by utilizing radiation.

• Nuclear Engineering and Technology
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• 제22권1호
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• pp.36-44
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• 1990

중ㆍ저준위 방사성폐기물 처분의 장기 안전성을 이론적으로 예측하기 위한 처분안전성평가 전산코드인 CALM이 개발되었다. 이 CAL.M은 처분장 재포화모델, 처분장에서의 지하 핵종 이동모델, 생태계에서의 핵종이동 및 방사선피폭선량 모델로 구성되어 있다. 개발된 평가코드의 유용성을 확인하기 위해 가상처분장에 대한 안전성 평가를 수행하였다. 그 결과 이 연구를 통해 개발된 CALM은 중ㆍ저준위 방사성폐기물 처분 안전성 평가에 유용하게 사용될 수 있음이 확인되었다.