• 자원ㆍ환경경제연구
• /
• 제24권1호
• /
• pp.109-139
• /
• 2015

현행 국가통계인 에너지밸런스 표는 우리나라 에너지 부문의 현황파악의 기초지표임에도 불구하고 IEA 기준의 에너지밸런스 표와 체계 및 수치상의 큰 차이가 있다는 선행연구를 근거로, 본 연구에서는 서로 다른 통계체계를 갖는 2009년 에너지경제연구원(KEEI) 기준의 에너지밸런스 표와 국제에너지기구(IEA) 기준의 에너지밸런스 표의 비교를 위한 기초적인 틀을 마련하고, 그 구체적인 차이를 백분율 값으로 비교 분석하여 보았다. 에너지원별, 세부 용도별로 그 구체적인 차이를 산정해 본 결과, 1차에너지공급과 에너지전환에서 에너지유가 32% 이상의 큰 차이가 나타났고, 최종에너지소비에서는 비에너지의 납사가 석유 화학에서 14.58%의 차이를 보이고 있는 등 최종에너지소비 기준으로 KEEI 에너지밸런스 통계가 IEA 통계에 비해 3.58% 크게 나타남을 확인하였다. 에너지통계는 이를 기반으로 하는 연구 및 정책 결정에 중요한 기초자료가 된다는 점에서 추가 연구와 개선을 위한 대책 마련이 필요해 보인다.

• Journal of Nutrition and Health
• /
• 제22권6호
• /
• pp.423-437
• /
• 1989

A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 16 college age men and women, 20 to 26 year of age, by measurement of energy intakes and changes in body energy(BE) content(intake/balance technique), keeping their normal living pattern and maintenance body weight. Energy intake was measured by bomb calorimetry and estimated by food table. Fecal energy loss was calculated from nitrogen excreted. Fat mass was determined from body density estimated from skinfold tickness. 1) Gross energy (GE) intakes calculated from food table was not only 13.4% lower than those of bomb calorimetry but also lower 4 and 5% than metabolizable energy(ME) intakes for the male and female subjects, respectively. 2) Fecal energy loss was 7.2% and 6.9% proportion of the gross energy intake for the male and female subjects, respectively. 3) Mean daily metabolizable energy intakes estimated by subtract fecal and urinary energy loss was 2467kcal for the male subjects and 1897kcal for the female subjects. 4) Total body energy change estimated from body composition change over 31 days was decreased 7672kcal for the male subjects and 2689kcal for the female subjects. 5) Mean daily energy expenditure was 2714kcal (45kcal/kg of body weight) for the male subjects and 1984kcal(40kcal/kg of body weight) for the female subjects. 6) The estimated energy expenditure of college-age subjects in this study provide evidence to support the Recommended Dietary Allowances for energy of Korean normal adult.

• 한국건축시공학회지
• /
• 제11권3호
• /
• pp.247-255
• /
• 2011

한국은행에서 2000년도에 발행된 산업연관표를 적용한 주요 건축자재의 에너지소비량과 $CO_2$ 배출에 대한 원단위 DB는 있지만 2005년, 2007년에 발행된 산업연관표를 이용한 원단위 DB는 없는 실정이다. 본 연구에서는 최근에 발행된 2005년, 2007년도 산업연관표를 이용하여 주요 건축자재에서 발생되는 에너지소비량 및 $CO_2$ 배출 원단위 값을 산정하고자 한다. 주요 건축자재의 에너지소비량 및 $CO_2$ 배출원단위 산출을 위한 방법은 산업연관표를 이용한 DB 구축 방식을 바탕으로 산출하였으며, 건설현장에서 주로 사용되는 16가지의 건설자재는 선별하여 적용하였다. 기존 연구결과에서 제시한 2000년도 산업연관표를 적용하여 산출된 원단위 DB 값과 비교한 결과 근소한 차이를 보이고 있어 본 연구의 산출방법이 적정한 것으로 판단하였다. 2005년, 2007년도 산업연관표를 이용하여 산출한 에너지소비량과 $CO_2$ 배출 원단위 값은 감소세를 보이고 있는 것으로 나타났으며, 시멘트와 철근을 주원료로 하는 자재에서 가장 많은 에너지소비량 및 $CO_2$ 배출 원단위 값을 나타났다. 본 연구의 결과를 통해 국내 실정에 적합한 건설자재 생산단계에서 발생되는 환경부하의 간접적인 예측이 가능할 것으로 사료된다.

• Nuclear Engineering and Technology
• /
• 제31권2호
• /
• pp.236-255
• /
• 1999

An improved mechanistic model was developed to predict a convective boiling critical heat flux (CHF) in the vertical round tubes with uniform heat fluxes. The CHF formula for subcooled and low quality boiling was derived from the local conservation equations of mass, energy and momentum, together with appropriate constitutive relations. The model is characterized by the momentum balance equation to determine the limiting transverse interchange of mass flux crossing the interface of wall bubbly layer and core by taking account of the convective shear effect due to the frictional drag on the wall-attached bubbles. Comparison between the present model predictions and experimental CHF data from several sources shows good agreement over a wide range of How conditions. The present model shows comparable prediction accuracy with the CHF look-up table of Groeneveld et al. Also the model correctly accounts for the effects of flow variables as well as geometry parameters.

• Earthquakes and Structures
• /
• 제24권4호
• /
• pp.247-258
• /
• 2023

Multiple pounding tuned rolling mass damper (MPTRMD) distributed in the cavity of voided slabs is proposed to passively control multi-story frame structures, which disperses the mass of the oscillator to multiple dampers so that the control device can be miniaturized without affecting the vibration control performance. The mechanism and the differential motion equations of the MPTRMD-controlled multi-degree-of-freedom system are derived based on the Lagrange principle. Afterward, this advanced RMD is applied to a simplified 20-floor steel frame to evaluate the seismic control performance in the numerical analysis. A four-storey frame structure equipped with MPTRMD is then taken for a shaking table test to verify its effectiveness of control performance. The pounding mechanism has been detailed studied numerically and experimentally as well. The numerical and experimental results show that the proposed damper is practically promising not only for its prominent control performance but also for its lightweight and space-saving. Additionally, the pounding mechanism influenced by the variable impact parameters exhibits a balance between the two effects of motional limitations and energy dissipation.

• Journal of Nutrition and Health
• /
• 제34권7호
• /
• pp.809-820
• /
• 2001

The purpose of the study was to find out the rich sources of vitamin B-complexes in Korea. Thirty kinds of vitamin B-complex (thiamin, riboflavin, and niacin) rich foods were selected based on vitamin content in 100g edible portion, single serving size, 100kcal energy content, and 1999 national annual food supply data. The results were summarized as follows: \circled1 Most of the thiamin rich foods selected were fishes: half of the foods selected was fishes when based on the contents in single serving size. On the other hand, about half of the foods selected were vegetables when based on the thiamin contents in 100kcal energy content. A relatively large number of food groups were included such as fishes, vegetables, beans, grains, meats, etc. when based on the contents in 100g edible portion, and national food supply data. \circled2 Most of the riboflavin rich foods selected were fishes and shellfishes, and vegetables: half of the foods selected were fishes and shellfishes when based on the content in 100g edible portion; two-thirds of the foods selected were vegetables when based on the content in single serving size; half of the foods selected were vegetables when based on the content in 100kcal. \circled3 The most important niacin sources are fishes: Most than 60% of the foods selected were fishes when based o the 100g edible portion, single serving size, and 100kcal energy content. Laver is very important source of all 3 vitamin B-complexes in Korea when based on the content in 100g edible portion, 100kcal energy content, and national annual food supply but not in single serving size. On the other hand, rice is rice is sources of all 3 vitamin B-complexes when based on the national annual food supply, but not in single serving size. On the other hand, rice sources of all 3 vitamin B-complexes when based on the national annual food supply, but is not included in 30 rich foods selected based on the content in 100g edible portion, single serving size, and 100kcal energy content. Mushrooms are also very important food sources of thiamin, riboflavin, and niacin when based on the vitamin content in 100g edible portion, single serving size, and 100kcal energy content but not included in 10 rich food selected based on the national food supply data.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2009년도 학술발표회 초록집
• /
• pp.529-534
• /
• 2009

Climate models, both global and regional, have increased in sophistication and are being run at increasingly higher resolutions. The Land Surface Models (LSMs) coupled to these climate models have evolved from simple bucket models to sophisticated Soil-Vegetation-Atmosphere Transfer (SVAT) schemes needed to support complex linkages and processes. However, some underpinnings of terrestrial hydrologic parameterizations so crucial in the predictions of surface water and energy fluxes cause model errors that often manifest as non-linear drifts in the dynamic response of land surface processes. This requires the improved parameterizations of key processes for the terrestrial hydrologic scheme to improve the model predictability in surface water and energy fluxes. The Common Land Model (CLM), one of state-of-the-art LSMs, is the land component of the Community Climate System Model (CCSM). However, CLM also has energy and water biases resulting from deficiencies in some parameterizations related to hydrological processes. This research presents the implementation of a selected set of parameterizations and their effects on the runoff prediction. The modifications consist of new parameterizations for soil hydraulic conductivity, water table depth, frozen soil, soil water availability, and topographically controlled baseflow. The results from a set of offline simulations are compared with observed data to assess the performance of the new model. It is expected that the advanced terrestrial hydrologic scheme coupled to the current CLM can improve model predictability for better prediction of runoff that has a large impact on the surface water and energy balance crucial to climate variability and change studies.

• 한국통신학회논문지
• /
• 제37권8B호
• /
• pp.637-646
• /
• 2012

최근 많은 응용 분야에서 무선 센서 네트워크 기술의 요구가 급증하고 있다. 특히 사람이 접근하기 어려운 환경에 센서 노드들을 설치하면 스스로 네트워크를 형성하고 사용자가 원하는 정보를 쉽게 획득할 수 있다. 그러나 무선 센서 네트워크에서 각 센서 노드들은 소형의 배터리를 사용하기 때문에 에너지를 효율적으로 관리해야 한다. 침입 탐지와 같은 응용에서는 침입자가 언제 나타날지 모르기 때문에, 에너지 효율이 높은 알고리즘으로 네트워크 수명을 연장시키는 노력이 요구된다. 본 논문에서는 침입 탐지 응용에서 데이터 전송의 신뢰성을 위해 트리 기반의 라우팅 알고리즘을 제안한다. 본 제안 방식은 데이터 집중으로 소모되는 에너지를 막기 위하여 부모와 자식 노드의 링크 설정 시 Load-balancing을 고려한 최적의 링크 비용을 계산하고, 효율적인 라우팅 테이블 관리로 센서 노드의 한정된 메모리 자원의 효율을 높였다. 또한 감시 정찰 환경에서는 침입자의 움직임을 예측할 수 없기 때문에 현실적인 군 운영 환경을 고려하여 다음의 시나리오를 설계하였고, 이에 대한 지연시간, 에너지 소모량 등의 성능을 시뮬레이션 결과를 통하여 입증하였다. 각 시나리오는 첫 번째로 침입자가 노드 설치 경로를 따라 이동하는 경우, 두 번째는 침입자가 노드 설치 경로를 가로지르는 경우, 마지막으로 침입자가 노드 설치 경로를 따라 이동하는 중에 이탈하는 경우로 구분하여 시험하였다.

• 대한기계학회논문집
• /
• 제11권1호
• /
• pp.177-188
• /
• 1987

본 논문에서는 연소기체의 열력학적 평형조성 계산을 위한 수식을 Gibbs의 자 유에너지 최소화법에 의하여 유도하고 이를 컴퓨터 프로그램화하여, Table 1의 특성을 지닌 연료에 대하여 ⅰ) 연소공기량에 따른 평형조성 및 단열불꽃온도, ⅱ) 연소온도 변화에 따른 평형조성의 변화를 계산함으로써 연소기체의 생성기구를 열력학적으로 해 석하였다.

• 한국식품과학회지
• /
• 제6권2호
• /
• pp.91-97
• /
• 1974

This paper was developed for production of the humanized milk, comprising similarly to the composition and characteristic of human milk. Humanized milk of superior quality can be made directly from the fresh raw milk mixed vegetable oil, corn syrup, whey powder, ${\beta}-lactose$, sugar, vitamin, ${\beta}-carotene$ and minerals showing formulation of the humanized milk at table 2. The improving effects of adding vegetable oil and corn syrup are both more reformed the chemical and physical properties of humanized milk. The former enhanced the essential fatty acid and energy source in this product, the latter has the most solving function in water and induced amount of emulsion and stabilizer. The products contain about 13% protein, 23% fat, 58.3% carbohydrate, 2% ash and ensue reasonably balance of essential amino acid, poly-unsaturated fatty acid for the requirement of infants and controlled component of the humanized milk such as human milk.