• 한국디지털건축인테리어학회논문집
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• 제8권2호
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• pp.47-56
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• 2008

The purpose of this study is to arrange the design elements and methods for sustainable community. After made the concept of sustainable community clear in the contemporary architecture and urban design, this study examines rural ecovillage, urban demonstration project, co-housing, new urbanism and urban village, and ecological township as the application modes of sustainable community. Through the cases of the application mode, the design elements for sustainable community were summarized as the followings: the symbiosis system with the nature, permaculture and edible landscape, identity, the technology for saving of resources and energy, the traffic system for the reduction of private motor use, mixed use development, and the housing with diversity. And the design methods for sustainable community were summarized as the followings: strategic planning, visioning, community action planning, workshops and charrette, environmental evaluation, and participation techniques.

• 한국조명전기설비학회지:조명전기설비
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• 제3권2호
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• pp.56-62
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• 1989

자연채광에 관한 에너지 해석을 하기 위해서는 주광조도를 예측하여야 하며, 주광조도를 예측하기 위해서는 천공상태를 추정할 수 있어야만 한다. 즉, 천공상태의 최저상태나 최소설계기준을 추정할 수 있어야만 자연채광에 의한 에너지 절약을 해석할 수가 있다. 천공상태를 추정하는데에는 CIE에서 개발한 정적 천공모델이 많이 이용되어 왔다. 그러나 천공은 정적광원이 아니라 시간에 따라 동적으로 변하고 있음으로 자연채광설계에서 에너지의 영향을 평가하기 위해서는 보다 융통성이 있는 천공모델이 요구된다. 따라서 이 논문은 그동안 동적천공을 나타낼 수 있도록 개발된 비표준천공의 추정방법, 동적 천공상태의 추정방법, 주광조도와 천공휘도의 추정방법, 주광의 유용성 평가방법 등을 비교분석함으로써, 앞으로 우리나라 기후상태에 적합한 자연채광용 천공모델을 개발하는데 기초자료화하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.591-594
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• 1999

The application field of photovoltaic system has been increased widely. In the application of photovoltaic system, the utility interactive photovoltaic system(UIPVS) has benefits of not only the home energy saving in domestic system but also reduction of peak power which threaten the capacity of power plant equipment when the maximum power consumption is occurred in daytime. This paper represents the effect of the nonlinear AC load which connected to the UIPVS with parallel connection and introduces the active power filtering(APF) techniques to the UIPVS for the reactive power compensation. The enhancement of source side power quality using APF algorithm is verified using simulation.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.4170-4175
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• 2015

지구 온난화로 인한 국제적 위기가 초래됨에 따라 전 세계는 지구온난화의 주범인 온실가스를 줄이기 위해 에너지 소비를 절감하기 위한 여러 기술들을 도입하고 시행 중이다. 우리나라는 총에너지의 30%를 건물에서 소비하고 있으며, 건물 에너지를 관리하기 위해 BAS 및 BEMS을 운영하고 있지만, 현재 BEMS는 효율적인 에너지 관리를 위한 정보표현기술이 미흡한 실정이다. 따라서 본 연구에서는 BEMS의 운영효율향상을 위해 세종시 첫마을에 위치한 참샘초등학교 BEMS를 대상 으로 연구를 진행하였다. BIM을 이용하여 건물 공간정보 Web 모델을 생성하고 에너지 시각화를 위해 로컬데이터베이스를 구축하였다. 그리고 건물 공간정보 Web모델과 로컬데이터베이스를 Web Browser로 연동하여 에너지정보를 시각화 하였다. ISO/IEC 9126 국제표준을 근거하여 정량적 평가를 수행하였으며, 2달간 본 시스템을 운영하여 약 16%의 에너지 절감을 확인 할 수 있었다. 우리는 3D Web Browser를 통해 BEMS의 운영효율향상을 가져올 것이라 기대한다.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제4권9호
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• pp.315-320
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• 2015

클라우드 컴퓨팅에서 서버 가상화는 한 대의 물리적인 서버를 다수의 가상머신으로 분할하여 다양한 운영체제 및 애플리케이션을 구동하는 기술이다. 가상머신의 마이그레이션은 현재 실행 중인 가상머신을 소스 호스트에서 다른 물리적인 장치인 타깃 호스트로 이동하는 것이다. 가상머신의 라이브 마이그레이션은 작업 수행 성능의 최적화와 저전력 지원 및 에너지 절감, 결함포용, 노드들 간의 부하 균형을 제공하기 위한 필수적인 요소이다. 본 논문에서는 오픈소스 기반의 적응적 VM 라이브 마이그레이션 기법을 제안한다. 이를 위해 적응적 VM 마이그레이션 시점을 결정하는 VM 모니터링 모듈을 제안하고 오픈소스 기반 전가상화를 지원하는 하이퍼바이저를 설계하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.169-172
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• 2008

Land-use or land-cover classification of satellite images is one of the important tasks in remote sensing application and many researchers have been tried to enhance classification accuracy. Previous studies show that the classification technique based on wavelet transform is more effective than that of traditional techniques based on original pixel values, especially in complicated imagery. Various wavelets can be used in wavelet transform. Wavelets are used as basis functions in representing other functions, like sinusoidal function in Fourier analysis. In these days, some basis functions such as Haar, Daubechies, Coiflets and Symlets are mainly used in 2D image processing. Selecting adequate wavelet is very important because different results could be obtained according to the type of basis function in classification. However, it is not easy to choose the basis function which is effective to improve classification accuracy. In this study, we computed the wavelet coefficients of satellite image using 10 different basis functions, and then classified test image. After evaluating classification results, we tried to ascertain which basis function is the most effective for image classification. We also tried to see if the optimum basis function is decided by energy parameter before classifying the image using all basis function. The energy parameter of signal is the sum of the squares of wavelet coefficients. The energy parameter is calculated by sub-bands after the wavelet decomposition and the energy parameter of each sub-band can be a favorable feature of texture. The decision of optimum basis function using energy parameter in the wavelet based image classification is expected to be helpful for saving time and improving classification accuracy effectively.

• KIEAE Journal
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• 제17권3호
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• pp.5-13
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• 2017

Purpose: Various studies have been performed to address the issue of increased energy use by buildings. In particular, research on complex envelopes that combines diverse envelope element techniques is currently in progress in the building sector. The present study aimed to develop an awning system using a light shelf, and to verify its validity through performance evaluation. Method: In the present study, a testbed was established for the performance evaluation of the awning system using a light shelf, and the uniformity ratio and lighting energy consumption were compared and analyzed relative to those with no awning and light shelf installation (Case 1), awning installation (Case 2), and light shelf installation (Case 3). Result: 1) In the present study, an awning system using a light shelf (Case 4) where an opening is made on the awning screen and natural light can be introduced through the light shelf located at the bottom was developed. 2) The optimum standard for Case 4 obtained through the performance evaluation was a 0.6m lighting length and a 2m extension length at a light shelf angle of $30^{\circ}$. 3) Case 4 with the optimum standard had a 5.5% lower uniformity ratio than Case 2, but had a higher uniformity ratio than Case 1 and Case 3. 4) Case 4 with the optimum standard showed 13.3%, 44.6%, and 0%~8.7% lighting energy reductions compared to Case 1, Case 2, and Case 3, respectively. 5) Based on the above results, Case 4 suggested in the present study was found to be effective for indoor light environment improvement and lighting energy reduction.

• 한국인터넷방송통신학회논문지
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• 제14권5호
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• pp.167-172
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• 2014

근래 들어 세계적으로 에너지에 대한 관심이 날로 증폭되어 가고 있다. 세계경제계의 화두 역시 녹색 에너지이고 각국 정부 역시 녹색 에너지를 경제회복의 선봉장으로 두고 있다. 한 국제연구소는 2030년까지 전 세계가 이 녹색 에너지 분야에만 투자하는 돈이 7조 달러로 한화로 환산하면 대략 7,000조원에 이를 것으로 전망하기도 하였다. 이에 우리나라 역시 이러한 녹색 에너지에 동참하고 있다. 전력을 생산하기 위해서는 전력 생산 시설과 연료 공급이 필수적이지만 공급에는 한계가 있다. 생산량을 증가 하는 것보다 더 중요한 것은 생산된 전력을 효율적으로 절감하는 것이다. 현재 사용 중인 에너지관리는 에너지를 소모하는 장비들의 효율적인 제어를 위하여 환경을 측정하여 설치된 장비를 조절하는 방법을 사용하고 있다. 그러나 에너지에 대한 절감 부분을 해결하기 위하여 국가나 기업체 등에서 많은 정책을 내놓았으나 번번이 해결되고 있지는 못하고 있는 현실이다. 본 논문에서는 에너지관리를 위하여 ICT기술을 이용하려고 한다. 에너지를 사용하는 환경의 변화를 최소화하면서 축척된 데이터를 활용한 방법으로 장비를 제어하는 스마트에너지관리시스템을 제안하고자 한다.

• 수산해양기술연구
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• 제40권1호
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• pp.17-22
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• 2004

This study was carried out at the CWC of Chosun university for the purpose of resistance performance improvement of planing hull, and the results of the tests were confirmed cooperatively with WJFEL. G/T 100 ton class planing hull form was selected, and the improvement of hull form including appendages were performed by using some model test techniques. The model test scope comprises resistance relative tests including wave profile observation, trim and sinkage measurement and flow visualization tests at full load and trial conditions for one bare hull and for two appended hulls. The final wedge and spray strip combined with improved hull form showed about 1.0 knot speed improvement at both of full and trial conditions, and outstanding improvement for fore wave phenomena.

• Journal of Biosystems Engineering
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• 제3권2호
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• pp.100-113
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• 1978

Drying grain with conventional artificial drying methods requires great quantities of petroleum fuels. Depletion of fossil fuel increases the need of the utilization of solar energy as an alternative to petroluem fuels for drying grain , an energy intensive agricultural operation. Many techniques for the utilization of solar energy in grain drying have been developed, however, there are many problems in adopting solar energy as an energy sources for drying grain. Futhermore, very little research has been done on solar grain drying in Korea. This study was conducted to evaluate the availability of solar energy for drying of rough rice in Chuncheon, Suweon, and Jinju areas based on 50year meteorological data, and to analyze experimentally the performance of a solar air collector for dying grain, and to find the effects of solar heated air compared to unheated air on the rate of drying and energy consumption required for drying of rough rice. The results of this study was may be summarized as follows ; 1. Monthly average daily total radiation on a horizontal surface in October was 260.6 ly/day for Chuncheon, 240.3 ly/day for Suweon , and 253.4 ly/day for Jinju area, respectively. 2. the ratio of monthly average daily diffuse radiation to daily total radiation on a horizontal surface was approximately 0.41 for Chuncheon, 0.45 for Suweon, and 0.44 for Jinju area, respectively. 3. Although the statistical distribution curves of daily total radiation for the three locations were not identical , the differences among them were not large and may be neglected for many practical purposes. 4. I was estimated that the optimum tilting angle of the collector in October was approximately 46 degrees for Chuncheon and Suweon and 45 degrees for Jinju. 5. The ratio of the total radiation on a optimum tilting plane to that on a horizontal plane was estimated to be 1.36 for Chuncheon, 1.31 for Suweon, and 1.27 for Jinju , respectively. 6. The collection efficiency of the solar air collector ranged from 47. 8 to 51. 5 percent at the air flow rates of 251. 1-372.96 $m^3$/hr. High efficiency remained nearly , constant during the best sunshine hours, 10 a.m. to 2 p.m. and decreased during other hours. More energy was collected as the air flow rate incresed. 7. The average temperature rise in the drying air from the solar collector for the test period varied from $6.5^\circC$ to $21.8^\circC$ above the ambient air temperature. 8. Solar-dried rough rice averaged 13.7 percent moisture (w.b.) after 130 hours of drying with the air flow rate of 1. 64 ccm/$m^3$, and rough rice dried with natural air averaged 15.1 percent moisture (w.b.) after 325 hours of drying with the same air flow rate. 9. Energy saving of 2.4 kwh per $m^3$ percentage point of moisture removed was obtained from solar heated air drYing. The solar bin used 53.3 percent less energy per percentage point of moisture removed than the natural air bin.