• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1993.10a
• /
• pp.171-176
• /
• 1993

초정밀 공작기계의 구조물은 Sub-micron의 운동정밀도를 갖추어야 초정밀기계로서의 기능이 유지된다. 특히 가공기의 베드구조물은 구동요소간의 상대 위치를 정.동적으로 규정 해주는 중요한 기본구조물이므로 고강성, 고쇠감성,열안정성, 경년변화에 대한 치수의 안정성등의 성능이 요구되며, 이를위해 공간적인 형상 설계 및 구조재의 선정에 고도의 기술이 필요하다. 따라서 본 연구는 낮은 고유진동수의 특성을 갖으면서 하중의 설치높이의 변화에서도 고유진동수가 일정히 유지되고 또한 구조물의 중심변화에 대한 수평조절이 가능하면서 자동제어가 가능한 공기스프링을 초정밀 가공기의 방진시스템으로 활용방안에 대하여 연구하였다.

• Water for future
• /
• v.8 no.2
• /
• pp.56-60
• /
• 1975

Traditional descriptions of water movement in soils and of calculations of infiltration rates neglect the air movement and its compressibility. The movement of two fluids in the bounded layered porous medium is treated analytically and computer simulations are conducted for given boundary conditions and initial saturation profiles. The movement of a given saturation across the interface between the different soil layers is theoretically developed by considering the conservation of mass. It is shown that the existence of the interface affects the infiltration rate when the average total velocity is greater than zero. The transition from one layer to another layer cause a change in the capillary drive and consequently influences the infiltration rate.

• Proceedings of the KAIS Fall Conference
• /
• 2010.05b
• /
• pp.1086-1088
• /
• 2010

본 연구는 지하 구조물의 내벽에서 발생하는 습윤(濕潤) 및 결로를 방지하는 내벽체에 관한 것으로, 사방으로 연결조립 가능한 벽체판넬의 한쪽을 수직 지지프레임에 끼움 조립한 상태에서 타카핀으로 벽체판넬 및 수직 지지프레임을 동시 관통하여 내벽에 고정한 후 상기 수직프레임에 다른 벽체판넬의 일측을 중첩되게 조립하는 방법으로 지하 구조물에 내벽체를 편리하게 시공할 뿐만 아니라 공기를 단축하며, 상기 내벽체의 구성부품이 매우 간소하면서 가격이 저렴하여 공사비를 대폭 절감할 수 있는 시공이 편리한 지하 구조물용 내벽체의 개발에 관한 것이다.

• Journal of the KSME
• /
• v.22 no.6
• /
• pp.471-476
• /
• 1982

1.열펌프 시스템의 성능은 최적설계를 하므로서 이론적, Rankine C.O.P에 접근시킬 수 있다. 2.. 산업체 중저온 폐열회수이용에는 열펌프가 매우 유망하며 냉온수를 동시에 이용하는 경우는 더욱 유리하다. 3. 우리나라 산업계에서 보통 투자회수기간을 3년으로 본다면 전력시설용량을 500kw 이상의 산업용 소동력, 대동력의 경우 열펌프의 성적계수는 약 3.5 정도가 하한으로 볼 수 있다. 4. 공기 또는 물 열원의 가정용 열펌프는 전력비가 비싸므로 아직은 실용성이 없다.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.11a
• /
• pp.241-242
• /
• 2023

This paper discusses an innovative acoustic membrane developed by doAZ Co., Ltd., offering enhanced noise barrier and dust control for urban construction and demolition, surpassing the performance of traditional non-woven fabrics. The membrane is made from recyclable bubble sheets and designed to be seamlessly integrated into single and double-row scaffolding systems, ensuring broader applicability and sustainability.

• Journal of the Society of Disaster Information
• /
• v.19 no.3
• /
• pp.608-623
• /
• 2023

Purpose: Recently, the number of logistics warehouses has been on the rise. In addition, as the number of such logistics warehouses increases, number of fire accidents also increases every year, increasing the importance of preventing fires in large logistics warehouses. Method: investigated aspirating smoke detectors that are emerging as adaptive fire detectors in logistics warehouses. Then, through fire simulation (FDS), logistics warehouse modeling was conducted to compare and analyze the detection speed of general smoke detectors and aspirating smoke detectors according to four stages of fire growth and three locations of fire in the logistics warehouse. Result: Growth speed in Slow-class fires and Mediumclass fires, the detection speed of aspirating smoke detectors was faster regardless of the location of the fire. However, in Fast-class fires and Ultra-Fast-class fires, it was confirmed that the detection speed of general smoke detectors was faster depending on the location of the fire. Conclusion: It was confirmed that the detection performance of the aspirating smoke detector decreased as the fire growth speed increased and the location of the fire occurred further than the receiver of the aspirating smoke detector. Therefore, even if an aspirating smoke detector is installed in a warehouse that stores combustibles with high fire growth rates, it is judged that an additional smoke detector is attached far away from the receiver of the general smoke detector to increase fire safety.

• Korean Journal of Construction Engineering and Management
• /
• v.14 no.5
• /
• pp.35-43
• /
• 2013

Nowadays the widely used media in architecture include visualizations, animations and three-dimensional models. 3D digital methods using active CAM(Computer Aided Manufacturing) and CNC(Computerized Numerical Control) imaging have been developed for accurate shape and 3D measurements in freeform buildings. In contrast to a conventional building using auto CAD system and others, the proposed digital optimization method is based on a combination of 3D numerical data and parametric 3D model for design and construction. The objective of this paper is therefore to present digital optimization process for constructability of freeform building. The method can be useful in the effective implementation of an error-proofing process of freeform building during design and construction phase. 3D digital coordinate data can be used effectively to identify correct size of structural and finish members and installation location of each members in construction field. In addition, architects, engineers and contractors can evaluate design, materials, constructability and identify error-proofing opportunities. Other project participants can also include representatives from all levels of management, departments as well as workers and key subcontractors' personnel, if necessary. The 3D digital optimization process is therefore appropriate to serious variations in freeform shape. For future study, the developed digital optimization method is necessary to be carried out to verify the robustness and accuracy for constructability in construction field.

• Journal of the Society of Disaster Information
• /
• v.19 no.2
• /
• pp.439-450
• /
• 2023

Purpose: When conducting fire inspections in Korea, there are objects that violate the fire protection regulations that require a straight line distance of more than 5m between the air inlet and the discharge section if the floor area is less than 400m2, and this paper analyzes the reasons and conducts a model experimental study to support the need for related fire protection regulations. Method: Domestic firefighting objects were investigated and confirmed, domestic and foreign papers, policies, and laws and regulations were examined, and spaces with a straight line distance of less than 5m and more than 5m between the air inlet and discharge section were selected and analyzed through model experiments in a living room of less than 400m² . Result: When examining the domestic fire protection regulations (NFPCNational Fire Perpormance Code), the separation distance between the air inlet and the outlet is more than 5m when the floor area is less than 400m² , but as a result of the actual investigation, it was confirmed that there are firefighting objects that cannot keep the separation distance. In addition, when a paper review of overseas fire protection regulations for a straight line distance of more than 5m showed that there was no regulation on the straight line distance between the air inlet and the discharge section, the model experiment showed that the discharge speed was better when the straight line distance between the air inlet and the discharge section was more than 5m than when it was less than 5m. Conclusions: In this study, when examining overseas fire laws and regulations by comparing the performance of the fire protection ratio for the straight line distance between the air inlet and the exhaust section, there is no mandatory regulation for the straight line distance, but the domestic fire protection regulations (NFPCNational Fire Perpormance Code) require more than 5m. It is hoped that this will be reflected in the design stage in the future, and a foundation will be laid to reduce the responsibility and burden of fire superintendents.

• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 1997.05a
• /
• pp.55-58
• /
• 1997

대기오염의 주요원인은 소각로 연소가스와 자동차의 배기가스로 이들 이동 오염원에서 배출되는 오염가스는 일산화탄소, 탄화수소, 질소 및 황산화물 둥이고 이들은 공기중의 산소와 반응하여 광화학반응을하여 오존을 생성하며 기타 미세먼지, 수분과 반응하여 스모그를 생성하여 인체의 호흡기 계통 질병을 유발케한다. (중략)

• 월간 기계설비
• /
• s.40
• /
• pp.50-56
• /
• 1993

장인상 대한주택공사 기계설치 1처 과정은 모든 건축물의 고층화가 가속화되고 있는 가운데 배관설비 규정의 내용과 제정 배경을 살펴보고, 규정 적용상의 효과와 문제점을 검토함으로써 공동주택 배관시스템 개발의 방향을 제시한 원고를 (사)공기조화$\cdot$냉동 공학회의 기술자료(제22권 제3호)에 게재, 본지에서는 그 내용중 일부를 요약 발췌 게재한 것임을 밝혀드립니다.