• 한국항공우주학회지
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• 제35권9호
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• pp.850-857
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• 2007

인공위성 전력계의 설계 분석은 위성 전체의 무게, 크기 및 성능을 결정하는 중요 변수로 작용한다. 특히 위성체 에너지 균형 분석의 경우 전력 시스템의 용량, 설계 제한 조건의 결정 및 위성체 운영 성공 여부를 결정할 수 있는 중요한 분석이다. 본 논문에서는 저궤도 위성 개발을 위한 새로운 에너지 균형 분석 프로그램을 소개하고 타 저궤도 위성 설계 자료를 이용한 시험 결과를 일례로 기술하였다. 시험 결과 본 논문에서 제안한 에너지 균형 분석 프로그램은 위성체 전력계의 최적 사이징 뿐 아니라 위성체 운영 기간 동안 궤도상에서의 위성체 에너지 균형 상황 예측에도 활용할 수 있음을 보였다.

• Journal of Nutrition and Health
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• 제28권4호
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• pp.259-267
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• 1995

A study was conducted to investigate nitrogen balance and to estimate daily nitrogen requirement in 43 Korean female college students students maintaining their usual diet and activity levels. Nitrogen intake and excretion were measured in two separate peroids about one month apart, each period lasting for 3 days. Nitrogen intake was assessed by duplicate portion analysis of diet, and N excretion in faces and urine were measured during the study period. Mean daily nitrogen intake level was 129.3mg/kg B.W and the apparent digestibility of nitrogen was 76%. Mean daily urinary nitrogen excretion was 113.5mg/kg BW. 895 of total nitrogen intake. Mean daily nitrogen balance of subjects was -14.5mg/kg BW. Mean daily requirements of nitrogen for 0 balance, calculated by regression analysis of N balance and energy-adjusted N intake. were 1) 197.mg/kg B.W with the present energy intake level of the study subjects. 2) 157mg/kg B.W when energy intake is sufficient to maintain energy balance, and 30 130mg/kg B.W. when energy intake is Korean RDA level for moderate activity. When energy intake level is sufficient to meet their requirement, daily protein requirement for 0 balance is about 1.0g/kg B.W. The results of this study indicate that nitrogen intake level of young female college students is not sufficient to meet their requirements, and they should increase protein intake together with increase in energy intake.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.679-680
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• 2011

This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

• Journal of Nutrition and Health
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• 제27권4호
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• pp.336-346
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• 1994

balance and to estimate daily energy requirement in 43 Korean female college students maintaining their usual diet and activity level. Energy intake and expenditure were measured in two separate periods about one month apart, each period lasting for 3 days. All the subjects participated in both periods. Energy intake was assessed by two methods ; weighed diet record and duplicate portion analysis of diet minus fecal and urinary excretion. Mean daily energy intake level calculated from diet records was 28.5 kcal/kgB.W(1, 476 kcal/day), and similar to the level of 27.8 kcal/kgB.W(1, 438 kcal/days) obtained from the chemical analysis of duplicate portions. Mean daily energy expenditure, calculated from activity records of each subject, was 34.6 kcal/kgB.W, or 1.39 times BMR, which corresponds to light activity level. Mean daily energy balance of subjects was -5.9 kcal/kgB.W. Mean daily requirement of energy, calculated from the activity records of the subjects, was 34.6 kcal/kgB.W, similar to the level of the Korean RDA for light activity level. The results of this study indicate that 1) the activity level of the study subjects corresponds to the sedentary level ; 2) present Korean RDA for energy for light activity is adequate for the subjects ; and 3) the subjects should increase their energy intake since they are largely in negative energy balance.

• 전기학회논문지
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• 제60권6호
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• pp.1103-1111
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• 2011

This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

• Journal of Astronomy and Space Sciences
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• 제34권3호
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• pp.225-235
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• 2017

The energy balance in a satellite needs to be designed properly for the satellite to safely operate and carry out successive missions on an orbit. In this study, an analysis program was developed using the MATLAB(R) graphic user interface (GUI) for nanosatellites. This program was used in a simulation to confirm the generated power, consumed power, and battery power in the satellites on the orbit, and its performance was verified with applying different satellite operational modes and units. For data transmission, STK(R)-MATLAB(R) connectivity was used to send the generated power from STK(R) to MATLAB(R) automatically. Moreover, this program is general-purpose; therefore, it can be applied to nanosatellites that have missions or shapes that are different from those of the satellites in this study. This power simulation tool could be used not only to calculate the suitable power budget when developing the power systems, but also to analyze the remaining energy balance in the satellites.

• 터널과지하공간
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• 제21권4호
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• pp.297-306
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• 2011

본 연구에서는 지하 압축공기에너지 저장공동 주변 지하수 및 압축공기의 유체유동과 열전달 거동 해석을 위한 다상다성분 열유동 해석 결과를 이용하여 지하 저장공동의 열역학적 에너지수지 분석을 통한 에너지 효율평가를 실시하였다. 복공재인 콘크리트 라이닝이 충분한 기밀성능을 발휘할 경우, 주입 압축과정에서 저장공동으로부터 손실되는 에너지의 대부분은 콘크리트 라이닝 및 주변 암반에의 열전도를 통해 발생함을 확인하였다. 지하 압축공기에너지 저장공동의 에너지 효율은 압축공기 주입온도에 민감한 결과를 보였으며, 주입온도가 주변 암반의 온도에 근사할 경우, 손실된 에너지의 대부분이 토출 팽창과정에서 저장공동으로 유입 회수되는 결과를 보였다. 한편, 콘크리트 라이닝의 열전도특성이 저장공동의 에너지효율에 미치는 영향은 크지 않았다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.93-97
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• 2010

액체로켓엔진 단계식 연소 사이클에 대한 에너지 발란스 프로그램을 개발하였다. 엔진을 추력실, 터보펌프, 터빈, 예연소기, 공급계 부품 등으로 모듈화 하여 각 모듈 프로그램을 제어하는 방식을 사용하였다. 이를 통해 에너지, 질유량, 압력의 균형을 맞추었으며 대표적인 단계식 연소 사이클인 스페이스 셔틀 메인 엔진의 자료를 바탕으로 비교 검증하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1080-1084
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• 1999

Carbon (C) and nitrogen (N) balance technique was used to determine energy balance in Rhode Island Red (RIR) and White Leghorn (WL) laying hens fed maize-and broken rice (BR)- based diets. Carbon and nitrogen intake and outgo were determined for three days on ad libitum fed diets followed by 2/3 of ad libitum intake for next three days. Carbon analysis was done by using four 'U' tubes in which carbon dioxide released during bomb calorimetry was absorbed on drierite in tube 1 and 2 whereas tube 3 and 4 contained sodalime self indicating granule. Carbon in $CO_2$ was determined by an open circuit respiration system. Energy retention (E, kcal) was calculated as E = 12.386 C (g) - 4.631 N (g). By regressing metabolisable energy (ME) intake on energy balance, maintenance ME requirement of RIR was 128 whereas, that of WL hens was $144kcal/kg\;W^{0.75}/d$. Effciency of utilization of ME for maintenance from BR-based diet in RIR hens was equal but in WL hens it was 11% less than maize-based diet.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권3호
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• pp.857-872
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• 2014

Recent researches reveal that great benefit can be achieved for data gathering in wireless sensor networks (WSNs) by employing mobile data collectors. In order to balance the energy consumption at sensor nodes and prolong the network lifetime, a multi-track large-scale mobile data collection mechanism (MTDCM) is proposed in this paper. MTDCM is composed of two phases: the Energy-balance Phase and the Data Collection Phase. In this mechanism, the energy-balance trajectories, the sleep-wakeup strategy and the data collection algorithm are determined. Theoretical analysis and performance simulations indicate that MTDCM is an energy efficient mechanism. It has prominent features on balancing the energy consumption and prolonging the network lifetime.