• 한국태양에너지학회 논문집
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• 제22권4호
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• pp.1-9
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• 2002

This study is on the design and evaluation of Zero Energy Solar House(ZeSH) including active solar heating system. Various innovative technologies such as super insulation, passive solar systems, super window, ventilation heat recovery system...etc were analyzed by individual and combination for the success of ZeSH. The ESP-r simulation program was used for this. Simulation results shows that almost 77% of heating load can be reduced with the following configuration of 200mm super insulation, super windows, passive solar system and 0.3 ventilation rate per hour. Active solar heating system (ASHS) was designed for the rest of the heating load including hot water heating load. The solar assisted heat pump is used for the auxiliary heating device in order to use air conditioner but not included in this study. The yearly solar fraction is 87% with a solar collector area of $28m^2$. The parametric studies as the influence of storage volume and collector area on the solar fraction was analyzed.

• 수산해양기술연구
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• 제21권2호
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• pp.142-150
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• 1985

1. 반구형 각의 분포 및 집중하중에 의한 좌굴응력 해석은 변형된 각의 형상에 따라 타원체 각의 응력으로 해석함이 타당하다. 2. 일정 한계이상의 형상계수를 갖는 반 구형각에 대하여서는 재료상수를 형상계수의 승수로 고려한 수정된 임계좌굴 하중으로 탄소성 좌굴을 판정함이 더 양호한 결을 준다. 3. 탄소성 좌굴에 있어서 소모된 소성변형 에너지를 계산하기 위하여 항성변형 에너지를 계산하기 위하여 항상선를 따르는 에너지법을 이용하면 양호한 결과를 얻을 수 있다.

• 국제초고층학회논문집
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• 제1권2호
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• pp.81-85
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• 2012

Vertical meteorological conditions encountered by super tall buildings, such as wind speed, temperature and humidity, vary due to their height. Therefore, it is necessary to consider these environmental changes to properly estimate the heating and cooling loads, and to minimize the energy demands for HVAC in super tall buildings. This paper aims to analyze how vertical meteorological changes affect heating and cooling loads of super tall buildings by using numerical simulation. A radiosonde, which observes atmospheric parameters of upper air such as wind speed, wind direction, temperature, relative humidity and pressure, was used to provide weather data for the building load simulation. A hypothetical super tall building was used for the simulation to provide quantified characteristics of the heating and cooling loads, comparing the lower, middle and upper parts of the building. The effect of weather data on the heating and cooling loads in super tall building was also discussed.

• 한국멀티미디어학회논문지
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• 제11권12호
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• pp.1706-1715
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• 2008

In a super-peer based P2P network, the network is clustered and each cluster is managed by a special peer, which is called a super-peer. A Super-peer has information of all the peers in its cluster. This type of clustered P2P model is known to have efficient information search and less traffic load than unclustered P2P model. In this paper, we compute the message traffic cost incurred by peers' query, join and update actions within a cluster as well as between the clusters. With these values, we estimate the optimal number of super-peers that minimizes the traffic cost for the various size of super-peer based P2P networks.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2016년도 춘계학술대회
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• pp.135-136
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• 2016

초고강 콘크리트를 활용한 부잔교는 강재부잔교에 비해 부식의 염려가 없어 내구성과 동적안전성이 우수하고, 일반 콘크리트에 비해 경량구조물로 건현확보가 유리하다. 현재 국내 연구개발 결과 SUPER concrete는 100MPa까지는 강섬유의 배합없이 일반골재만으로 배합이 가능하여 고부식성 환경의 항만구조물의 내구성에 적합한 강도이다. 부잔교는 상부슬래브에 작용하는 차량(DB-18) 또는 군집하중(5kN/m2)과, 외부 벽체 및 하부슬래브에 작용하는 파력의 수평과 양력성분을 견디도록 하여야 한다. 설계 파랑은 인천 연평도지역을 대상으로 50년 빈도 유의파와 주기에 해당하는 파력을 산정하여 X,Y축 위치에 따라 수평 및 양력성분을 재하하였다. 전체계 해석시 부잔교는 연직방향 경계조건이 없는 상태에서 부력 산정이 가능하도록 기하비선형 및 시간이력해석기법을 응용하였다(Strand 7). 부잔교 슬래브에 대해서는 실물모형실험을 통해 DB-18하중 재하에 따른 안전성을 확인하였다.

• Wind and Structures
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• 제25권2호
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• pp.101-129
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• 2017

Local transient extreme wind loads caused by group tower-related interference are among the major reasons that lead to wind-induced damage of super-large cooling towers. Four-tower arrangements are the most commonly seen patterns for super-large cooling towers. We considered five typical four-tower arrangements in engineering practice, namely, single row, rectangular, rhombic, L-shaped, and oblique L-shaped. Wind tunnel tests for rigid body were performed to determine the influence of different arrangements on static and dynamic wind loads and extreme interference effect. The most unfavorable working conditions (i.e., the largest overall wind loads) were determined based on the overall aerodynamic coefficient under different four-tower arrangements. Then we calculated the one-, two- and three-dimensional aerodynamic loads under different four-tower arrangements. Statistical analyses were performed on the wind pressure signals in the amplitude and time domains under the most unfavorable working conditions. On this basis, the non-Gaussian distribution characteristics of aerodynamic loads on the surface of the cooling towers under different four-tower arrangements were analyzed. We applied the Sadek-Simiu procedure to the calculation of two- and three-dimensional aerodynamic loads in the cooling towers under the four-tower arrangements, and the extreme wind load distribution patterns under the most unfavorable working conditions in each arrangement were compared. Finally, we proposed a uniform equation for fitting the extreme wind loads under the four-tower arrangements; the accuracy and reliability of the equation were verified. Our research findings will contribute to the optimization of the four-tower arrangements and the determination of extreme wind loads of super-large cooling towers.

• 한국지반신소재학회논문집
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• 제18권3호
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• pp.89-100
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• 2019

본 연구에서는 동재하시험을 통해 매입공법으로 선단이 암반에 근입된 초고강도 PHC 말뚝의 지지력 특성을 분석하였다. 초고강도 PHC 말뚝은 일반 고강도 PHC 말뚝에 비해 콘크리트의 강도가 높아 허용구조내력을 향상시킬 수 있었다. 초고강도 PHC 말뚝의 최적 설계를 위해서는 지반지지력도 증가된 구조내력과 균형을 맞출 수 있도록 증가되어야 할 것이다. 오늘날, 지반지지력 검증을 위한 동재하시험 시 경험적으로 고강도 PHC 말뚝과 유사한 항타에너지를 초고강도 PHC 말뚝에 적용하고 있는 실정이다. 동재하시험 결과를 기반으로 초고강도 PHC 말뚝의 지지력에 영향을 미치는 요소들을 분석한 결과, 선단지지력에 대해 선단 주변지반의 표준관입시험 N값의 영향은 미미하였으며, 항타에너지가 증가할수록 선단지지력이 증가하는 경향을 보였다. 그러나 주면마찰력의 경우, 항타에너지의 증가에 따른 변화가 나타나지 않았다. 또한, 허용지지력을 판단하는 Restrike 시험시 선단지지력의 영향은 극히 작아 허용지지력 판단시 합리적인 방안이 필요하다.

• Journal of information and communication convergence engineering
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• 제8권3호
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• pp.295-300
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• 2010

Recent researches of network structure are moving to high-level networks because there are already many research results of low-level network. Especially, current network services has been changed to the multimedia service using multicast routing such as IPTV(Internet Protocol Television) service. And then previous multicast services were provider oriented. So previous multicast structures were organized server/client model. But future multicast services will make user oriented services. Therefore there will be many service providers in the future. At this point, we study P2P network for supporting multi provider. So we research load balancing and contents lookup protocols in P2P network. In this paper, we propose network protocol and system based on super peer P2P for load balancing and efficiently service search. And we considered mobile environment for mobile IPTV.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권2호
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• pp.85-92
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• 2000

30 kVA rotating-field type Super-Conducting Generator is built and tested with intensive FE(Finite Element) analysis. The generator is driven by VVVF inverter-fed induction motor. Open Circuit Characteristic(OCC) and Short Circuit Characteristic(SCC) are presented in this paper. Also, the test result under the light load(up to 3.6 kW) are given. From the design stage, 2-D FE analysis coupled with the external circuit has been performed. The external circuit includes the end winding resistance and reactance as well as two dampers. When compared with the test data, the FE analysis results show a very good agreement.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1637-1642
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• 2009

This study evaluates the energy performance of super high-rise residential buildings with e-QUEST simulation and calculates the annual cooling and heating load. The result of this study have concluded that the most influential factor is the characteristics of the window and also suggest the most efficient window system from the result of calculation of different glasses' cooling and heating load. The result of this study shows that The most efficient method to enhance the energy performance is to use low reflective 3 pairs Low-E glass and Low-E coating(inside of outer glass) pair glass.