• Steel and Composite Structures
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• 제5권2_3호
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• pp.247-258
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• 2005

This paper outlines the current steel design climate and describes some recent and unusual designs using structural steel or composite steel and concrete which have been carried out in Hong Kong and the East Asia region. Composite structural systems for very tall buildings are outlined. A case study of concept designs for one of these is presented. Two further case studies are presented: a refurbishment project where the use of steel and innovative strengthening techniques allowed an additional five stories to be built on an existing reinforced concrete frame and a monumental sculpture.

• 한국산업융합학회 논문집
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• 제20권5호
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• pp.425-430
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• 2017

This study propose CAE analysis of fire damper and design of the damper control system. Through the design of the damper system for ANSYS-CFX heat transfer. As a result of the analysis, continuance equation of the damper control. Climate system. Finaily, We have obtained a fire damper solution by using orthogonal array. The fire damper of the set of fixture and alveolus are made by using a CAE software. Also, the optimum design offshore structures. The new H-120 class fire damper was designed. In the near future, fire resistance test was carried out to obtain class H-120 thermal insulation of fire dampers according to a hydrocarbon fire conditions. The test results showed that the insulation of the damper blade was an important factor in the fireproof performance of fire dampers concerning the coaming length minimum 500mm on the unexposed side as specified test standard.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.319-322
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• 1999

Land surface hydrological conditions have been considered to play an important role in the global and regional climate variability. Especially, snow, soil moisture, surface temperature, vegetation and rain are the key parameters which should be observed in the global scale. In this paper, new algorithms for these land surface hydrological parameters have been developed by introducing frequency and polarization dependencies of these parameters in the microwave radiative-transfer equations. The algorithms were applied to the TRMM Microwave Radiometer. (TMI) and validated by using the ground data obtained in the Tibetan Plateau. The estimated snow, soil moisture, surface temperature, water content of vegetation and rain patterns corresponded reasonably to the observed ones.

• 한국태양에너지학회 논문집
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• 제21권3호
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• pp.9-18
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• 2001

This paper reports on an theoretical study of heat transfer from evaporative cooling system by the flow of recirculated water over the roof. In this system tile water is distributed at the top of the pitched roof, collected at the bottom by a gutter and recirculated by a pump. To analysis the system, the energy balance equations are developed and solved using a finite difference method. The calculation results show a good agreement with the measured ones obtained from our experiment. Based on the results, it was seen that the roof-evaporative cooling system reduced the heat flux significantly compared with the conventional roof structure even in the hot-humid summer climate of Korea.

• 펄프종이기술
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• 제41권3호
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• pp.13-21
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• 2009

Pulp and paper industry is a typical plant industry which usually consume lots of water and energy. Recently, environmental issues have become more important due to climate changes around the world, and reinforcement in the regulatory content in transfer and management of chemical material and that in environmental regulations for waste water and air. Paper industry is a source material recycle industry which recycle or reuse waste paper, recyclable wood, planned plantation or lumber from thinning and waste wood. Hence it can be said that paper industry is the representative industry for earth environment and of 21th century.

• 한국산업융합학회 논문집
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• 제25권1호
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• pp.101-110
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• 2022

For this purpose, the authors proposed and proved usefulness of the modified mean skin temperature which is integrated mean radiation temperature and the effect of floor contacted heat conduction. The mean radiation temperature is applied form factor between half cross-legged human body and surrounding wall of indoor. In addition the floor contacted heat conduction is applied heat transfer coefficient of half cross-legged human body. Eight Korean young men were targeted for the experiment. From the experiment the authors excerpted physiological reaction and psychological reaction in Ondol environment which is combined physiccal environmental factor of artificial climate chamber, air and floor temperature. As a result of the experiment it is confirmed that heat conduction has more impact than heat exchange from existing research for the heat exchange between half cross-legged human body and surrounding wall in Ondol thermal environment. Thereby, it is proved the effectiveness of the modified mean skin temperature which is added floor contacted temperature to the Ondol thermal environmental evaluation index.

• KEPCO Journal on Electric Power and Energy
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• 제2권2호
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• pp.285-291
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• 2016

In chemical-looping combustion, pure oxygen is transferred to fuel by solid particles called as oxygen carrier. Chemical-looping combustion process usually utilizes a circulating fluidized-bed process for fuel combustion and regeneration of the reduced oxygen carrier. The performance of an oxygen carrier varies with the active metal oxide and the raw support materials used. In this work, spraydried Mn-based oxygen carriers were prepared with different raw support materials and their physical properties and oxygen transfer performance were investigated to determine that the raw support materials used are suitable for spray-dried manganese oxide oxygen carrier. Oxygen carriers composed of 70 wt% $Mn_3O_4$ and 30 wt% support were produced using spray dryer. Two different types of $Al_2O_3$, ${\gamma}-Al_2O_3$ and ${\alpha}-Al_2O_3$, and $MgAl_2O_4$ were applied as starting raw support materials. The oxygen carrier prepared from ${\gamma}-Al_2O_3$ showed high mechanical strength stronger than commercial fluidization catalytic cracking catalyst at calcination temperatures below $1100^{\circ}C$, while the ones prepared from ${\alpha}-Al_2O_3$ and $MgAl_2O_4$ required higher calcination temperatures. Oxygen transfer capacity of the oxygen carrier prepared from ${\gamma}-Al_2O_3$ was less than 3 wt%. In comparison, oxygen carriers prepared from ${\alpha}-Al_2O_3$ and $MgAl_2O_4$ showed higher oxygen transfer capacity, around 3.4 and 4.4 wt%, respectively. Among the prepared Mn-based oxygen carriers, the one made from $MgAl_2O_4$ showed superior oxygen transfer performance in the chemical-looping combustion of $CH_4$, $H_2$, and CO. However, it required a high calcination temperature of $1400^{\circ}C$ to obtain strong mechnical strength. Therefore, further study to develop new support compositions is required to lower the calcination temperature without decline in the oxygen transfer performance.

• 한국산학기술학회논문지
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• 제14권2호
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• pp.955-961
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• 2013

본 연구는 친환경 건축의 대안으로 부각되고 있는 한옥의 열환경 평가를 수행하기 위하여 한옥을 구성하고 있는 건축요소의 전열 메카니즘을 규명하기 한옥건축부재의 규격화와 모델링을 통하여 열환경을 평가하였다. 최근 친환경 건축, 생태건축의 모델로 일반의 한옥 선호도는 높아지고 있으나, 한옥의 우수성이 정성적으로만 평가되고 있다. 이에 한옥의 건축재료 및 형태와 같은 건축요소를 고려, 한옥 건축요소의 Geometry를 작성하여 솔리드 모델을 구축하고, 열환경 평가의 도구로써 CFD를 적용하여 한옥의 실내 열환경을 평가하고자 하였다. 본 연구에서는 복잡한 형태의 Geometry 작성이 가능한 CATIA와 환경 시물레이션 Code인 FLUENT 등의 상용 Code를 활용함으로써 연구의 신뢰성을 높이고자 하였다. 본 연구는 일차적으로 서울지방에 건축된 한옥의 기준모델을 설정하여 벽, 천정, 바닥, 창호 등 건축요소의 부위별 형태를 고찰하고, Geometry작성의 입력자료로 사용하기 위하여 각 부위별 치수체계를 구축하였다. 건축요소의 부위별 각각의 형태를 솔리드 모델로 구축하기 위하여 단계별로 벽, 천정, 바닥, 창호 등에 관한 건축요소의 Geometry를 모델링하여 CFD 입력자료로 활용하여 열환경 시물레이션을 수행하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.15-21
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• 2007

Due to a decreasing tendency of river runoff in the Laohahe River basin in North China, quantitative analysis was made with the aid of the conceptual Xinanjiang model under the background of nature climate variability as well as human-induced climate change according to the long-term observational hydrometeorological data. In the past, the human effect on surface water resources was estimated by investigating the impact of human activities on each item in the equation of water balance, so as to calculate water quantity of each item in the original natural status. It seems to be clear conceptually. It is appropriate just for the case of direct impact, such as water transfer from one basin to another, water storage by various scales of hydraulic projects, besides a huge amount of investigation and indeterminate statistics data when applied in practice. It is difficult for us to compute directly water consumption due to the implementation of measures for soil conservation, the improvement of farming techniques in agriculture, the growth of population in towns and villages, and the change of socioeconomic structure. In view of such situation, the Xinanjiang model was used to separate human impact from the climatic impact on water resources. Quantitatively human activity made river runoff decrease by 1.02, 50.67, 58.06 mm in 1960's, 1970's, 1980's, respectively, while by 97.2 mm in 1990's in the sense of annual average in the Laohahe River basin.

• 한국군사과학기술학회지
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• 제20권6호
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• pp.767-773
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• 2017

Infrared stealth is an important technology for naval ships. This technology helps improve the anti-detection performance and survivability of naval ships. In general, the infrared signature of naval ships are categorized into internal and external heat source. External signature are generated by ship surface heating by solar flux as well as the complicated heat transfer process with the surrounding weather condition. Modern naval ships are equipped with seawater injection nozzles on the outside for nuclear, biological and, chemical, and these nozzles are used to control external signature. Wide nozzle placement intervals and insufficient injection pressure, however, have reduced seawater dispersion area. To address this problem, nozzle installation standards must be established. In this study, an actual-scale experimental system was implemented to provide the evidence for nozzle installation standards in order to reduce the infrared signature of naval ships. In addition, the environmental conditions of the experiment were set up through computational fluid dynamics considering the ocean climate data and naval ship management conditions of South Korea. The dispersion distance was measured using a high-resolution thermography system. The flow rate, pipe pressure, and dispersion distance were analyzed, and the evidence for the installation of seawater injection nozzles and operation performance standards was suggested.