• 에너지공학
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• 제22권2호
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• pp.211-225
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• 2013

본 연구에서는 서로 다른 위도의 도시 유형별로 주택과 건물 구성비를 가진 3지역을 선정하여 대상 지역별로 2008년 1년간(1.1~12.31)의 실제 운전실적을 이용하여 지역난방 사용자의 일일 및 연간 열소비 패턴을 분석하고, 지역별 상호 차이점을 파악하기 위하여 주택과 건물의 열소비 패턴을 비교 분석하였다. 특히 본 연구에서는 실제 주택 및 건물 지역난방 사용자가 사용한 열소비 패턴을 매시간대별로 파악하고, 연결 열부하(난방면적 ${\times}$ 단위열부하 : 시설용량과 지역난방 배관망의 설계기준이 되는 열부하로 난방면적에 용도별 단위열부하를 곱하여 산출[Gcal/h])와의 관계를 분석하여 일일, 연간 및 최대 부하율 결과값을 도출함으로써 주택 및 건물 지역난방 사용자 비율에 따른 최적의 열원시설 용량산정이 가능케 하고 수요개발(해당 시설용량으로 열공급이 가능한 지역난방 사용자의 범위로 각 사용자기계실의 연결열부하 합과 같음.)단계에서의 정확한 방향을 제시할 수 있는 근거를 도출하였다.

• 한국지열·수열에너지학회논문집
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• 제16권4호
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• pp.31-38
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• 2020

The investment in the technology of using a combined heat source is insufficient, which utilizes the advantages of various heat sources to maximize the potential energy and at the same time increases the performance of the heat pump. In this study, as basic data for the development of a high-efficiency hybrid heat pump system that actively connects and uses various heat sources, simulations were conducted for the heat pumps in two cases where geothermal and hydrothermal heat were applied respectively. In May, COP increased by about 27.3% compared to geothermal heat. In February, the COP percentage decrease of hydrothermal heat compared to geothermal heat is -6.9%. In May, total energy consumption can be reduced by 21.1% when hydrothermal is applied compared to geothermal heat. In February, the total energy consumption increases by 3.4%.

• 설비공학논문집
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• 제17권1호
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• pp.82-87
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• 2005

The purpose of this study is to suggest the characteristics and actual state of energy consumption by the analysis of energy consumption data in an office building. This study examines and analyzes daily and monthly energy consumption of an office building located in Seoul, Korea regarding type of load and business classification within a building. The results are as follows. 1) Energy consumption of office building for each type of load show similar consumption patterns, regardless of seasons such as cooling period and heating period. 2) Out of all annual energy consumption, consumption for lighting took about $43\;\%,$ general electric Power about $23\;\%,$ emergency power $25\;\%,$ computer center $5\;\%$ and cooling power $4\;\%,$ showing that the consumption for lighting was highest, and the percentage of energy consumption for cooling power for operation of cooling facilities took the lowest percentage. 3) Annual gas consumption used for heating and hot water supply were $38,\;36\;\%$ for officetel and office respectively, and $26\;\%$ for arcade. 4) Electricity consumptions used for cooling power for each use of building, office and officetel recorded in July and August of cooling seasons. Even though it shows different patterns for each month, energy consumption showed unique pattern throughout the cooling seasons.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.95-99
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• 1994

Robot engineering is developed mainly in the field of intelligibility such as a manipulation. Considering the popularization of robots in the future, however, a robot should be studied from a viewpoint of saving energy because a robot is a kind of machine with a energy conversion. This paper deals with minimizing an energy consumption of a manipulator which is driven in a point-to-point control method. When a manipulator carries a heavy payload toward gravitation or the links are de-accelerated for positioning, the motors at joints generate electric energy. Since this energy can be regenerated to the source by using a chopper, the energy consumption of a manipulator is only heat loss by an electric and a frictional resistance of the motors. The minimization of the sum of these losses is reduced Lo a two-points boundary-value problem of an non-linear differential equation. The solutions are obtained by the generalized Newton-Raphson method in this paper. The energy consumption due to the optimum angular velocity patterns of two joints of a two-links manipulator is compared with conventional velocity patterns such as quadratic and trapezoid.

• 자원ㆍ환경경제연구
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• 제10권2호
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• pp.217-234
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• 2001

The use of district heating is expanding very rapidly in Korea. High population densities and the relatively cold winters make district heating an economically attractive option. About 8 percent of Korean houses are already using district heating and the government is seeking to aggressively expand this number. It has set a target of 15 percent of the residential heat market to be met by district heating in the year 2001. The main purpose of this paper is to analyze the consumption behavior of households using district heating. By pooling time-series and cross-sectional data for 12 apartment complexes in Seoul area, a single demand function is estimated and used to forecast the amounts of heat demanded by the individual households. The results shows that the level of consumption varies among households, depending on the non-economic factors such as the installation of individual metering equipment and the volume of apartment building. When individual metering equipment is installed, the level of annual heat consumption per household declines, on average, about 22.1 Mcal per square meters, which is equivalent to 834 won per square meter in terms of heating expenditures. In case that the apartment building was built in more than 6 stories, annual consumption level reduces additionally about 17.3 Mcal per square meters and, thus, save the expenditures by 649 Won per square meters, compared to the opposite case.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2122-2125
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• 2008

Because the reheating furnace consumes a large amount of energy to heat up the slabs, it is very important to find an optimal temperature patterns in the furnace for energy saving as well as uniform target temperature at the exit of the furnace. In this study, the temperature profiles in the slab are determined by solving the transient one-dimensional heat conduction equation in conjunction with boundary conditions with total heat exchange factors. The optimal temperature patterns are obtained to minimize the fuel consumption with satisfying the predetermined constraint conditions. The design optimization is performed by using a genetic algorithm and the optimal results are validated with results obtained from the PIDO tool, called as P.I.A.n.O.

• 한국지열·수열에너지학회논문집
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• 제14권4호
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• pp.61-67
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• 2018

Solar energy depends on the altitude and azimuth of the sun, and the amount of energy collected on the slope depends on the latitude of the area being installed. However, since most solar heating systems are fixed to the ground, it is necessary to analyze the optimal installation angle from the early design stage. However, problems arise when energy consumption is not considered together because heating systems are not used in the summer In this study, the optimum installation angles of the solar collectors according to the latitude of the installation area are not simply determined by the amount of energy collected, but because the system is overheated due to climate change or energy usage patterns, And the amount of additional energy input.

• 동력기계공학회지
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• 제8권2호
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• pp.24-30
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• 2004

In this paper, the optimal heating pattern of the furnace is sought to reduce the unnecessary energy loss. A finite difference method was used to estimate the transient temperature field of the billet in a furnace. Heat conduction equations were used in the interior nodes of the billet, while energy balances for conduction, convection, and radiation were considered in the boundary nodes. Several heating patterns for the furnace were tested and subsequently compared each other. The results showed that the temperature in the preheating zone should be set to relatively low. The temperature distributions of the billet are quite different from each other when different heating pattern are used, even though the heating patterns have the same amount of energy consumption. It reveals that there exists an optimal heating pattern to save the energy loss.

• 환경생물
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• 제34권4호
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• pp.272-280
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• 2016

Changes in land use and increase in urban energy consumption influence urban life. This study analyzed the characteristics and patterns of urban heat and presents management schemes to generate a comfortable and sustainable urban environment. The study aimed to demonstrate the positive effects of artificial ground greening on improving the microclimate through evapotranspiration using perennial herbs. We have designed a chamber that could control constant temperature and humidity, measure temperature reductions in each plant and changes in sensible heat and latent heat. This study identified Sedum kamtschaticum as the most effective plant in controlling temperature. At $22^{\circ}C$, $3.2^{\circ}C$ temperature reduction was observed, whereas four other plants showed a $1.5^{\circ}C$ reduction. At $25^{\circ}C$, $2.0^{\circ}C$ temperature reduction was observed. On the other hand, the use of Sedum sarmentosum resulted in the lowest effect. Zoysia japonica is the most commonly used ground covering plant, although the temperature reduction of Lysimachia nummularia was more effective at high temperature conditions. Sensible heat and latent heat were calculated to evaluate the thermal performance of energy. At a temperature >$30^{\circ}C$, L. nummularia and S. sarmentosum emitted high latent heat. In this study, we analyzed the thermal performance of green roof perennial plants; in particular, we analyzed the evapotranspiration and temperature reduction of each plant. Since the substrate depth and types, plant species, and seasonal change may influence temperature reduction and latent heat of green roofs, further studies are necessary.

• 한국빅데이터학회지
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• 제3권2호
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• pp.59-70
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• 2018

특정 지역의 고객을 대상으로 열을 공급하는 지역난방 서비스의 안정적인 운영을 위해서는 단기간의 미래 수요를 보다 정확하게 예측하고, 효율적인 방법으로 생산 및 공급하는 것이 무엇보다 중요하다. 그러나 열 소비에 영향을 미치는 요소가 매우 다양할 뿐만 아니라 개별 소비자 및 지역적 특성에 따라 소비 형태가 달라지기 때문에 일반적인 상황에도 적용될 수 있는 범용적 열 수요 예측 모형을 개발하는 것은 매우 어렵다. 따라서 본 연구에서는 실시간으로 확보할 수 있는 제한적인 정보만을 바탕으로 딥러닝 기법을 활용한 수요예측 모형을 개발하고자 한다. 해당 지역의 외기온도와 날짜로만 구성된 과거 데이터를 입력 변수로 하여 텐서플로의 인공신경망을 학습시키는 방법으로 수요 예측 모형을 개발하였다. 기존의 회귀분석 기법을 통해 예측된 수요의 정확도와의 비교를 통해 제안된 모델의 성능을 평가하였다. 본 연구의 열 수요 예측 모델은 단기적 수요 예측을 위해 실시간으로 확보할 수 있는 제한적인 변수만으로도 수요 예측의 정확도를 높일 수 있음을 보였다. 나아가 개별 지역에서는 지역적 특수성을 추가하여 수요 예측 정확도를 높이는 데 활용할 수 있을 것이다.