• 대한가정학회지
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• 제32권1호
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• pp.93-102
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• 1994

The purpose of this study was to investigate the suitability of several knit fabrics for the hadicapped children's slacks. After the observation and wearing test abrasion resistance pilling liquid water transport properties and heat transport properties of the fabrics were tested. As specimens cotton/polypropylene interlock knits and sweat absorbent polyester knit fabric were selected and compared to the cotton denim and wool fabrics. As a result of observation test importance of extensibility durability and comfort related properties were recognized. Through the wearing test depending on the handicap type and orthoses different location and grade of pilling were observed. Knit fabrics used in this experiment were as durable as woven fabrics and showed excellent heat and liquid water transport properties. It was concluded therefore that cotton/polypropylene and sweat absorbent polyester knit fabrics are suitable materials for handicapped children's slacks.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1195-1200
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• 2004

A fully coupled fluid flow, heat, and solute transport model was developed to investigate turbulent flow, solidification, and macrosegregation in a continuous casting process of steel slab with EMBR. Transport equations of mass, momentum, energy, and species for a binary iron-carbon alloy system were solved using a continuum model. The electromagnetic field was described by the Maxwell equations. A finite-volume method was employed to solve the conservation equations associated with appropriate boundary conditions. The effects of intensity of magnetic field and carbon segregation were investigated. The electromagnetic field reduces the velocity of molten flow in the mold and an increase in the percentage of C in steel results in a decrease of carbon segregation ratio.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.97-98
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• 2012

The rotary kiln is one of the most widely used industrial reactors for contacting gases and solids. Kilns are mainly used for drying, calcining and reducing solid materials. In an indirected fired rotary kiln, heat is supplied to the outside of the kiln wall. Heat transfer in indirected fired rotary kilns encompasses all the modes of transport mechanisms, that is, conduction, convection and radiation. This paper deal with the heat transfer characteristics of indirect fired rotary kiln for scale up.

• Nutrition Research and Practice
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• 제3권2호
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• pp.149-155
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• 2009

In this study, we investigated the heat effect of digestion-resistant fraction (RF) from soybean on retarding bile acid transport in vitro. The RFs from soybean retarded bile acid transport. A raw, unheated RF of soybean (RRF-SOY) was significantly more effective than the heated RF of soybean (HRF-SOY). The RS1 which physically trapped in milled grains and inaccessible to digestive enzyme after 18 hrs incubation level of content in RRF-SOY was found to be as high as 24.1% and after heating the RS1 of HRF-SOY was significantly reduced to 16.8%. The X-ray diffraction pattern of RF from soybean was altered after heat treatment. The RFs from soybean were characterized by peak at diffraction angles of $12.0^{\circ}$ and $20.0^{\circ}$ corresponding to RS content. Cellulose contents of RRF-SOY was 5% higher than that of HRF-SOY and pentosan contents of RRF-SOY was 5% higher than that of HRF-SOY, too. Whereas the hemicellulose content of RRF-SOY was 13% lower than HRF-SOY.

• Corrosion Science and Technology
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• 제21권4호
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• pp.243-249
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• 2022

The objective of the present study was to perform failure analysis of double-layered bellow (expansion joint), a core part of stress reliever, used to relieve axial stresses induced by thermal expansion of heat-transport pipes in a district heating system. The bellow underwent tensile or compressive stresses due to its structure in terms of position. A leaked position sufferred a fatigue with a tensile component for decades. A cracked bellow contained a higher fraction of martensitic phase because of manufacturing and usage histories, which induced more brittleness on the component. Inclusions in the inner layer of the bellow acted as a site of stress concentration, from which cracks initiated and then propagated along the hoop direction from the inner surface of the inner layer under fatigue loading conditions. As the crack reached critical thickness, the crack propagated to the outer surface at a higher rate, resulting in leakage of the stress reliever.

• Corrosion Science and Technology
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• 제22권2호
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• pp.115-122
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• 2023

This study aimed to elucidate causes of corrosion of heat transport pipes and air vents installed under a manhole of heat transport facilities and suggest effective anticorrosive measures by applying paints or adhesive tapes. It was found that air vent corrosion was attributed to corrosion under insulation caused by the inflow of water and the enrichment of chloride ions. The infiltrated water caused a hydrolysis of polyurethane foam (PUF) insulation by concentrating chloride ions at the interface between a pipe and the PUF. As insulator deteriorated, more chloride ions were eluted as confirmed by ion chromatograph (IC) analysis. As an effective method to prevent air vent corrosion, different types of paints and adhesive tapes with higher corrosion resistance on chloride ions were applied and environmental resistance tests were performed with those samples. Based on environmental test results of samples exposed to 10% HCl solution, it was revealed that a wax tape was the most adequate from a viewpoint of stability at operating condition, environmental resistance, surface treatment, and field applicability.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2007년도 추계학술 발표회
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• pp.187-192
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• 2007

메탄올 분해/합성 반응을 이용한 장거리 열수송 시스템에 대한 경제적 타당성 연구를 조사하였다. 본 연구는 열공급처에서 흡열반응을 이용하여 메탄올을 수소와 일산화탄소로 분해하여 이 반응생성물 가스를 수송관을 이용하여 열수요처로 이송한 후 열수요처에서 일산화탄소와 수소를 메탄으로 합성하며, 이 발열반응에서 발생하는 열을 회수하여 온수로 사용하는 개념이다. 메탄을 분해/합성 반응은 상대적으로 낮은 온도와 낮은 압력 그리고 높은 전화율을 이용한 장거리 열수송 반응의 대표적인 반응이 될 수 있다. 본 연구에서는 열공급처에서 15 km 떨어진 장소에서 1만 가구에 필요한 온수를 공급하기 위한 시스템의 설계 및 경제성을 검토하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.246-253
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• 2009

This study was conducted to investigate the effects of Chinese medicine granule (CMG, including Cortex Phellodendron, Atractylodes Rhizome, Agastache Rugosa and Gypsum Fibrosum) on absorption and transport of glucose in porcine small intestinal brush border membrane vesicles (BBMVs) under heat stress. Forty-eight 2-month-old Chinese experimental barrows were screened according to weight and litter origin, and then allotted to three groups and treated as follows: Normal temperature control group (NTCG; $23^{\circ}C$), high temperature control group (HTCG; $26^{\circ}C$ for 19 h, $40^{\circ}C$ for 5 h); Chinese medicine granule anti-stress group (CMGG; $26^{\circ}C$ for 19 h, $40^{\circ}C$ for 5 h) (n = 16 per group). The results showed that high temperature treatment decreased (p<0.05) the growth performance and intestinal glucose absorption but there was no change (p>0.05) in the expression of SGLT1 and GLUT2 genes in the small intestine of pigs compared with the NTCG. Dietary supplementation with CMG improved the growth performance, and increased the activity of disaccharidases in duodenum and jejunum of heat stressed pigs (p<0.05). CMG treatment increased (p<0.05) the protein levels of SGLT1 and GLUT2 in the small intestine, and up-regulated (p<0.05) the expression of SGLT1 and GLUT2 genes in the duodenum and jejunum but without changing (p>0.05) them in the ileum compared with the HTCG. These results indicated that CMG treatment significantly improved porcine growth performance, and increased intestinal glucose absorption and transport by BBMVs under heat stress, in addition to up-regulating the expression of SGLT1 and GLUT2 genes in porcine duodenum and jejunum.

• 한국결정성장학회지
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• 제7권1호
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• pp.27-40
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• 1997

The heat in Czochralski method is transfered by all transport mechanisms such as convection, conduction and radiation and convection is caused by the temperature difference in the molden pool, the rotations of crystal or crucible and the difference of surface tension. This study delvelops the simulation model of Czochralski growth by using the finite difference method with fixed grids combined with new latent heat treatment model. The radiative heat transfer occured in the surfce of the system is treated by calculating the view factors among surface elements. The model shows that the flow is turbulent, therefore, turbulent modeling must be used to simulate the transport phenomena in the real system applied to 8" Si single crystal growth process. The effects of a cusp magnetic field imposed on the Czochralski silicon melt are studied by numerical analysis. The cusp magnetic field reduces the natural and forced convection due to the rotation of crystal and crucible very effectively. It is shown that the oxygen concentration distribution on the melt/crystal interface is sensitively controlled by the change of the magnetic field intensity. This provides an interesting way to tune the desired O concentration in the crystal during the crystal growing.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.213-216
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• 2003

Efforts for better understanding of the interaction between groundwater recharge and thermal regime of the subsurface medium is gaining momentum for its diverse applications in water resources. A numerical model is developed to simulate temperature variations of the subsurface under time varying groundwater recharge. The model utilizes MacCormack scheme for finite difference approximation of the partial differential equation describing the conductive and advective heat transport. For the estimation of recharge rate, optimization of the model is realized by searching for the unknown parameters which minimize the root-mean-square error between simulated and measured temperatures. Simulation results for 22-year time series data of temperature measurements reveal that the proposed model can accurately simulate subsurface temperature variations resulting from the redistribution of the heat due to the movement of water and it can also estimate temporal variations of recharge. Seasonal variations of recharge and a linear relationship between precipitation and recharge are clearly reflected in the simulated results.