• 수산해양교육연구
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• 제25권3호
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• pp.733-742
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• 2013

The Korea has significant tidal current energy resources, but it is so hard to work underwater for tidal turbine installation. Therefore commercial diving work is very important for tidal current generator. Also, Jangjuk channel is vary famous as proper area to generate tidal current energy. Nevertheless, no one is studied about characteristics of commercial diving works with installation of tidal current generator. The purpose of this study is to introduce commercial diving with work types and investigate critical limits of diving working under the conditions, which are working only to minutes at slack tide during the neap tide. As the results, work types are five as like mooring installation, OMAS(Offshore Maintenance Access System), support structure installation, cable and turbine installation. Here, the original construction period is expected about 4 months, but the construction take 18 months to complete. The cause of extends construction period is insufficiency of researching tidal current conditions at the site and ignorance of slack tide which need to secure diving working time. Total diving working times are 110th during 18 months, the highest percentage of diving times is turbine installation about 43.6 %, and cable, mooring installation and support structure construction are 27.3 %, 15.5 %, 13.6 %, respectively. On the basis of this study, estimation of times of commercial diving is possible with work types of tidal current power, and has a significance as basic data to determining construction period.

• 한국건설관리학회논문집
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• 제7권3호
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• pp.112-121
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• 2006

본 연구는 사례대상 건물의 냉난방설계용량에 대한 냉온수 유닛의 설치 유형을 단일설치, 분할설치(균등분할), 분할설치 (차등분할)의 유형으로 구분하여 각각의 사례를 선정하고 LCC기법을 이용한 경제성 평가를 실시하였다. 이를 위하여 냉온수 유닛의 LCC 구성항목을 조사하고, 구성항목별 비용 자료를 조사하였다. 위와 같은 과정을 통해 예측된 각 설치 유형별 LCC를 상호 비교 분석함으로써 경제성 평가를 실시하였다. 상기와 같은 목적과 방법에 따라 진행된 본 연구의 결과를 요약하면 다음과 같다: 1) 냉난방설계용량에 대한 단일설치 사례와 분할설치(균등분할), 분할설치(차등분할) 사례를 선정하고 LCC 구성항목에 대한 자료조사를 통하여 초기투자비(냉동기 설치비, 냉각탑 설치비, 펌프설치비), 유지관리비(교체 수선비, 가스에너지비, 전기에너지비), 해체비(노무비, 폐기비, 잔존가치)를 고려하여 단위면적당$(100m^2)$분석기간 15년 동안의 LCC를 분석 하였다. 2) 냉온수 유닛의 단일설치, 분할설치(균등분할), 분할설치(차등분할)의 설치 유형에 따른 경제성 평가 결과 설치 유형 중 단일설치 유형이 가장 경제적인 것으로 분석 되었다.

• 한국인터넷방송통신학회논문지
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• 제14권6호
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• pp.119-123
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• 2014

본 연구에서는 익일부하예측 기능을 갖는 빌딩에너지관리시스템을 제시한다. 기존의 빌딩에너지 관리시스템은 빌딩내의 다양한 인프라를 이용하여 에너지를 감시 한다 그러나 이러한 시스템을 구현하기 위해서는 많은 인프라 구축비용이 소요 되어, 에너지 절감을 위한 인프라 구축비용과 실제 절감된 전기 요금을 비교 할 경우, 에너지 절감을 위해 투자한 비용을 전기 요금 절약으로 회수하는데 수년이 걸리고, 또한 인프라 설비 유지 보수를 고려할 경우, 결과적으로 에너지 절약 효과가 미비하다. 따라서 본 연구에서는 보다 저렴하고 합리적인 방법으로 빌딩의 에너지 소비를 억제할 수 있도록, 기상청데이터와 한전의 ISmart 데이터를 기반으로 데이터마이닝기법을 이용하여 빌딩의 익일 부하 사용량을 예측하고 이를 기반으로 빌딩 부하의 On/Off를 수행하도록 빌딩에너지관리시스템을 구현함으로써 상대적으로 저렴한 비용으로 빌딩에너지 사용의 합리화를 이루도록 하였다.

• 조명전기설비학회논문지
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• 제28권9호
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• pp.83-88
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• 2014

When DG interconnection into network is examined, details of the review are overvoltage, protective device malfunction, etc. In the case of protective device malfunction, replacing protective device into bi-directional protective device and installation NGR are the solution. Overvoltage at interconnection point occurs because the load is relatively less than DG output. When overvoltage at interconnection point occurs, DG interconnection is not permitted because this overvoltage affect other customers. Interconnection by installation new distribution line is one solution but it costs much money. Without installation new investment, change of NOP(Normal Open Point) position is a possible solution about DG interconnection into network.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2002년도 학술대회논문집
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• pp.349-354
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• 2002

A size of low-voltage conductor cables is determined by the voltage drop of a system, the cable impedance and the cable ampacity based on temperature correction factor in accordance with the condition of cable installation. Therefore, the proper temperature correction factor according to the condition of cable installation should be applied to determining the cable ampacity and also the skin effect and proximity effect, along with the kind and size of conductor and the condition of cable installation, should be properly considered to analyze the proper value of resistance and the reactance of the conductors. This paper addresses the systematic design flow for determining the size of low voltage level conductor cables in calculating the temperature character where error should be minimized in comparison with the general formula and which can be applied in design work for determining the size of conductor cables.

• Journal of Multimedia Information System
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• 제9권1호
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• pp.43-50
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• 2022

As the discourse on Anthropocene grows, this exploratory research investigates the interrelationship and interconnectivity between humanity and technology by analyzing a sound art installation created by the author. Crying Sea is a sound installation that uses plastic wastes collected from the shore to create symbolic narratives and artistic experience connecting humans, objects, and nature through interactive digital technology. In this installation, the audiences are guided to walk over the wastes, and the sounds created by the footsteps are recorded in real-time, which then are distorted and amplified into disturbing sounds through speakers filling up the room. In analyzing this artwork, three theories from technological, philosophical, and ecological backgrounds were used; specifically, Bernard Stiegler's pharmakon theory, Dona Haraway's cyborg manifesto, and Timothy Morton's dark ecology theory. A common factor revealed from all three theories by analyzing the Crying Sea is that humans, technologies, and all other entities within nature are interconnected and resonated. The awareness of this recursive relationship allows us to consider sustainable balancing.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.520-526
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• 2005

Automation in construction has been restricted to special classes of tasks. Curtain walls can be handled like standard construction materials; they are heavy but breakable, and are large but require precise installation. These characteristics make the installation of curtain walls ideal for robotic automation. There are two methods for developing construction robots: The first is approving the robot performance and applying it to the current construction methods. The second is admitting the limitation of the current robot technology and trying to optimize the current method of construction to apply the robot system. In this study, we derived the performance requirements of a curtain wall-installation robot. We also tested this robot at a real construction site and evaluated its performance. Finally, the results were analyzed, and we proposed additional research.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.95-104
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• 2013

This study set out to devise an optimized system to take into account life cycle cost(LCC) and ton of carbon dioxide($TCO_2$) by applying the weighted coefficient method(WCM) to "public-purpose" facility buildings according to the mandatory 5% and 11% of new renewable energy in total construction costs and anticipated energy consumption, respectively, based on the changes of the public obligation system. (1) System installation capacity is applied within the same new renewable energy facility investment according to the mandatory 5% of new renewable energy in total construction costs. Both LCC and $TCO_2$ recorded in the descending order of geothermal, solar, and photovoltaic energy. The geothermal energy systems tended to exhibit an excellent performance with the increasing installation capacity percentage. (2) Optimal systems include the geothermal energy(100%) system in the category of single systems, the solar energy(12%)+geothermal energy(88%) system in the category of 2-combined systems, and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system and the photovoltaic energy(12%)+solar energy(25%)+geothermal energy(63%) system in the category of 3-combined systems. (3) LCC was the highest in the descending order of photovoltaic, geothermal and solar energy due to the influences of each energy source's correction coefficient according to the mandatory 11% of new renewable energy in anticipated energy consumption. The greater installation capacity percentage photovoltaic energy had, the more excellent tendency was observed. $TCO_2$ recorded in the descending order of geothermal, photovoltaic and solar energy with the decreasing installation capacity of photovoltaic energy. The greater installation capacity percentage a geothermal energy system had, the more excellent tendency it demonstrated. (4) Optimal systems include the geothermal energy(100%) system in the category of single systems, the photovoltaic energy(62%)+geothermal energy(38%) system in the category of 2-combined systems, and the photovoltaic energy(50%)+solar energy(12%)+geothermal energy(38%) system and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system in the category of 3-combined systems.

• KIEAE Journal
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• 제14권6호
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• pp.53-58
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• 2014

Residental photovoltaic power system achieved remarkable results in distribution and activation through 'One Million Green Homes Program' led by the government. However, system maintenance and management after installation are relative unsatisfactory. Thus, problems, such as malfunctioning, decrease in efficiency, breakage, etc, are occurring in succession which means that expensive facilities are not used effectively. This study attempted to propose a more preferred alternative to the photovoltaic power system currently applied and installed to the housing by investigating and analyzing the said system, identifying management practices, and deriving problems. For this study, 48 houses equipped with photovoltaic systems in J City were chosen and they were analyzed after preliminary research and field investigation. The results revealed that most of the surveyed systems in J City are still in fairly good conditions. But the instruction and information regarding the appropriate operational management of those surveyed systems have not been delivered to the owner. Therefore, promotion education and related manual deployment should be done by the contractor. In terms of installation, inadequate system location and some warranty services are required to be improved, which are usually caused by a lack of careful planning and construction. In addition, the follow-up management needs to be provided about five years later after installation considering system deterioration.

• 전기학회논문지
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• 제64권3호
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• pp.357-364
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• 2015

The power system configuration is changed to solve increasing power demand. This changes in power system configuration with mesh-, network grid generate the problem of fault current increase. Superconducting fault current limiter (SFCL) has been expected the one of the solutions to solve this problem. And there has already been reported much to the application and research of SFCL in the power distribution system. However, the application and research of SFCL are insufficient in a transmission power system. Also, the fault current limiting effect by the SFCL varies with installation location of SFCL. Therefore, this paper constructed the power transmission system through experiment and analyzed installation location method of SFCL using the current rate of each circuit breaker (CB) according to fault location.