• Journal of the Korean Recycled Construction Resources Institute
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• 제7권4호
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• pp.431-437
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• 2019

The purpose of this study is to develop an organic-inorganic hybrid insulation materials which has an economic feasibility of organic level and excellent adiabatic performance and fire stability by impregnating organic materials with inorganic binder solutions. The organic base was commercial polyurethane sponge, and the inorganic binder slurry was prepared by mixing water and additives into recycled gypsum byproducts. As a result of evaluation of the developed materials, it was confirmed that it not only has excellent insulation performance of a thermal conductivity of 0.051 W/mK or less but also it is a semi-non-combustible materials specified in the Ministry of Land, Infrastructure and Transport Notice No. 2015-744. The developed materials can also be controlled for thermal conductivity and flame retardance according to density control during manufacturing process, and thus it can be applied to various insulation materials.

• Journal of the KSME
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• 제26권1호
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• pp.31-35
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• 1986

물질전달이 포함되는 교환기의 설계목표도 단순열교환기의 경우와 마찬가지로 여러 가지 주어진 제약조건(constraints; 예를들면 교환기의 제원이나 유체유동에 필요한 압력부하등)을 만족시키 면서 전달능력의 단위(number of transfer units, 이하 $N_{tu}$ 로 약함)를 최대로 해 주는데 있다. 그러나 교환장치들의 유형이나 형상에 따라 이같은 동일 목적을 위한 과정은 각양각색 이다. 본장에서는 직접 접촉식 교환기의 많은 종류중 물의 직접증발을 이용한 단열가습장치와 고체건조제 단열제습장치등 두가지의 해석과정을 예시하려고 한다.

• Journal of the Korean Society for Precision Engineering
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• 제19권11호
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• pp.9-17
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• 2002

최근에 초전도 산업과 저온 작동 정밀 센서 기술의 발전으로 극저온 냉동기 또는 극저온 한제에 의해 냉각된 저온 용기의 저온 유지 기술이 필요하게 되었다. 또한 의료용 MRI, 야간 투시경용 적외선 센서, 이동통신무선기지국용 초전도 필터 등과 같이 일반인들도 극저온을 이용하게 되어 보다 사용하기 쉽고 안정적인 저온용기가 요구되고 있다. 저온용기의 저온 유지 기술은 진공 및 복사 단열 기술 뿐만 아니라 극저온 발생기술과 진공 발생 기술이 같이 고려되어야 하는 복합기술로서 앞으로 전자, 정보 통신, 나노, 바이오 산업 등에도 널리 활용될 수 있는 기반 기술로 자리 매김 할 것으로 보여 관련 연구자들의 많은 노력과 관심이 요구된다.

• The Journal of Engineering Geology
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• 제17권3호
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• pp.483-494
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• 2007

The properties of fracture system on road-cut slopes along the Busan-Ulsan express way under construction are investigated and analyzed. Fracture spacing distributions show log-normal form with extension fractures and negative exponential form with shear fractures. Straight line segments in log-log plots of cumulative fracture length indicate a power-law scaling with exponents of -1.13 in site 1, -1.01 in site 2 and -1.52 in site 3. It is likely that the stability and strength of rock mass are the lowest in site 1 as judged from the analyses of spacing, density and inter-section of fractures in three sites. In contrast, the highest efficiency of the fracture network for conducting fluid flow is seen in site 3 where the largest cluster occupies 73% through the window map. Based on the field survey data, this study modified weighting values of the RMR system using a multiple regression analysis method. The analysis result suggests a modified weighting values of the RMR parameters as follows; 18 for the intact strength of rock; 61 for RQD; 2 for spacing of discontinuities; 2 for the condition of discontinuities; and 17 for ground water.

• 보일러설비
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• 통권6호
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• pp.76-79
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• 1988

• 보일러설비
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• 통권4호
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• pp.126-129
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• 1988

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 한국생물환경조절학회 1994년도 봄 심포지움 및 학술논문발표요지
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• pp.88-91
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• 1994

최근 국내에서도 시설원예가 급격하게 보급되고 있는 실정이다. 하지만, 시설원예가 에너지 소비형의 농경방식이라 지적되고 있는바 에너지절약형 온실의 개발이 필요할 것으로 판단되어, 본 실험실에서는 본 연구와 관련하여 비닐하우스의 벽체를 이중으로 하여 이중벽사이에 단열입자를 송풍기의 케이싱내로 직접 통하게하는 직송방식으로 충전ㆍ회수하는 실험을 실시한 바가 있으며, 그 결과 외기온의 평균이 -4.9$^{\circ}C$인 겨울철 야간에 입자를 충전한 이중비닐 하우스의 내부온도는 평균 9.8$^{\circ}C$로 단열성이 우수함을 알 수 있었다.(중략)

• The Journal of Engineering Geology
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• 제13권2호
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• pp.207-225
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• 2003

According to the data analysis of the regional fracture systems in southern Korea, the fracture orientations show three dominant sets : NNE, NW and WNW. A NNE set is the most abundant and includes most of the largest fractures. The highest fracture density is shown in the Taebaegsan mineralized area corresponding to Ogchon nonmetamorphic belt and the lowest one in the southwestern area of southern Korea. In addition, the density is higher in nonmetamorphic sedimentary rocks such as Choseon Supergroup. Pyeongan Supergroup, Daedong Supergroup and Kyeongsang Supergroup than in Precambrian basements and Jurassic granites. The regional fractures in southern Korea can be classified into four orders designated $F_1,{\;}F_2,{\;}F_3{\;}and{\;}F_4${\;}and{\;}F_4$ on the basis of their trace length. It is quite significant that fractures of each order are self-similar with respect to orientation and the combined fracture length distribution indicates a power-law distribution with an exponent of -2.04. As fractures were analyzed based on the tectonic provinces, Gyeonggj Massif and Kyeongsang Basin have all orders of fractures from $F_1$ to $F_4$. Most of the large scale faults may be ascribed to the products of slip accumulation through multiple deformation. Others besides $F_1$ fractures are thought to be evenly distributed through the whole area of southern Korea.

• KOREAN POULTRY JOURNAL
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• 제38권8호통권442호
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• pp.103-106
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• 2006

여름철만 되면 혹서로 인한 생산성 감소와 심지어 폐사가 속출하는 경우가 빈번히 발생하면서 사양가들은 혹서기 사양관리에 관심이 집중되는 시기이다. 특히 닭은 열에 민감한 동물로 여름철 열차단이 무엇보다 중요한 시점이다. 이에 본고는 7월 11일 서울 성수동에 위치한 전문 단열업체인 세원물산을 방문하여 여름철 단열의 중요성을 알아보았다.

• The Journal of Engineering Geology
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• 제9권1호
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• pp.31-43
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• 1999

This study aims to quantify the distribution characteristics of the fracture system for the numerical modeling of groundwater flow in the north-eastern area of Yosu peninsula. The study area is composed mainly of volcanic rocks and granite. The regional and site scale lineament in the range of magnitude Order 1 to Order 3 were analyzed from the geologic map, air-photograph and shaded relief map. The geometric parameter of Order 4 fracture system was acquired from the scanline survey on the ground surface. There is a similar trend in the preferred orientation between the regional lineament and the Order 4 fracture system except the Set 4 of Order 4 fracture system which is not prominent in the type. That is classified to three fracture sat of high dip angle and one of ow dip angle. From the lineament trend. The orientation of Order 4 fracture system has similar characteristics in each rock termination mode analysis, it is considered that the fracture system was developed systematically and sequentially from Set 1 to Set 4 Filling materials are distinct relatively in low dip angle set. The fracture spacing follows to lognoral distribution and the fracture frequency corrected by the modified Terzaghi correction ranges from 0.38 to 1.01 per mater in each fracture set. The fracture trace lenght also follows to lognormal distribution and ranges from 2.9m to 3.7m in each fracture set.