• 한국농촌건축학회논문집
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• 제17권2호
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• pp.9-16
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• 2015

This study comparatively analyzed thermal characteristics of the green color, which is currently used the most, and other various colors of a rooftop urethane water proofing sheet. This study also analyzed the cooling performance by color of the water proofing sheet that fused cooling paints, and presented the effective water proofing sheet color for building energy savings. The experimental results are as follows: (1) The value of L (brightness) diminished, and brilliance also became lower from the white color to the black color, and thus, it was confirmed that relatively more heat was absorbed. In a and b chromaticity, which is the color attribute that ignores brightness, no special relationship was identified. (2) Considering that the cooling performance effect is bigger in summer than winter, due to heat reflection, the white water proofing sheet is more effective in building energy savings than the green water proofing sheet that is currently used the most. (3) The water proofing sheet's color has an impact more on cooling performance than the color of the background side of a structure on which water proofing sheet is installed. The experiment object of gray, of which background side is similar to cement mortar, was lower by $5.7^{\circ}C$ than the white background side.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.132-135
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• 2007

In this study, hydroformability and mechanical properties of pre- and post- heat treated Al6061 tubes at different extrusion type were investigated. For the investigation, as-extruded, full annealed and T6-treated Al6061 tubes at different extrusion type were prepared. To evaluate the hydroformability, uni-axial tensile test and free bulge test were performed at room temperature and $250^{\circ}C$. Also mechanical properties of hydroformed part at various pre- and post-heat treatments were estimated by tensile test. And the tensile test specimens were obtained from hexagonal prototype hydroformed tube at $250^{\circ}C$. As for the heat treatment, hydroformability of full annealed tube is 25% higher than that of extruded tube. The tensile strength and elongation were more than 330MPa and 12%, respectively, when hydroformed part was post-T6 treated after hydroforming of pre- full annealed tube. However, hydroformed part using T6 pre treated tube represents high strength and low elongation, 8%. Therefore, the T6 treatment after hydroforming for as-extruded tube is cost-effective. Hydroformability of Al6061 tube showed similar value for both extrusion types. But flow stress of seam tube showed $20{\sim}50MPa$ lower value.

• 한국표면공학회지
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• 제19권2호
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• pp.31-43
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• 1986

The properties of the electroless nickel deposit mainly depends on the pH of the bath, the plating temperature, and the molar ratio of nickel to hypophosphite but they are also affected by its formulation and concentration of complexing and buffering agents. According to changeing the concentration of triethanolamine and boric acid, phosphorous contents, microsturcture, crystalline, hardness and wear resistance of deposits obtained from ammoniacal alkaline bath were investigated by EPMA, differential thermal analyser, X-ray diffractometer and wear tester. The results are as follows; (1) Increasing concentration of triethanolamine in the bath, the deposits is slightly inclined to increase its phosphorous content(3.7% P). (2) In the as-plated state, the deposits are not crystallized state but they are thermally unstable phase, and they are crystallized with precipitating $Ni_3P$ at 400$^{\circ}C$. (3) The deposit containing 2.3% P has higher hardness value in the as plated and heat treated state at below 300$^{\circ}C$ than those of 3.7% phosphorous deposit (1090Hk). But in the case of heat treating at 400$^{\circ}C$, the former has lower hardness value (1000Hk) than the latter and has remarkably Ni(III) orientation by heat treatment. (4) The 3.7% phosphorous deposit heat treated at 400$^{\circ}C$ has better wear resistance than hard chromium plating.

• 한국세라믹학회지
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• 제36권1호
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• pp.77-81
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• 1999

분말도가 포틀랜드 시멘트의 물성에 미치는 영향을 알아보기 위하여, 서로 다른 분말도(2300, 2500, 3000, 3500, 3500, 4500 $\textrm{cm}^2$/g)를 갖는 5종의 일반 포틀랜드 시멘트를 제조하여, Ca(OH)2 분석, 수화열, 유동성 및 물성 측정을 하였다. 그 결과, 시멘트의 분말도가 낮아짐에 따라 수화속도는 늦어졌고 수화열 및 압축강도는 떨어졌으나 유동성은 개선되었다. 특히 2300$\textrm{cm}^2$/g 시멘트의 경우, 수화열은 3500$\textrm{cm}^2$/g 시멘트에 비교해서 약 15% 감소하였다.

• 한국표면공학회지
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• 제20권2호
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• pp.49-59
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• 1987

The properties of $Cr_2O_3-Al_2O_3-SiO_2$ composite oxide coatings on steel surface were investigated. The results obtained were as follows: The microhardness of oxide coating layer increased with increasing heat-treatment temperature and $Cr_2O_3$ content in coating layer. The hardness showed the highest value (850Hv) treated at 700$^{\circ}C$ for $SiO_2:Al_2O_3:Cr_2O_3$=1:1:4. Increasing heat-treatment temperature, corrosion current density became lower and coating layer became denser. The corrosion current density showed the lowest value $(6.5{\times}10^{-5}\;Acm^2)$ treated at 750$^{\circ}C\;for\;SiO_2:Al_2O_3:Cr_2O_3$=1:1:3. These results were explained by protective layer which was formed during heat-treatment. The bonding between matrix and coating layer is expected to be made mechanically and chemically by the inter diffusion of Ni and Fe. The composite oxide coating was formed by softening of the binder with increasing heat-treatment temperature. The strengthening of coating layer is to be resulted from the dispersion of major oxide particles.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.83-92
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• 2012

This study was performed for analyzing the general composition and the change in the quality of soymilk-derived yogurts manufactured by adding skim milk and whey powder to soymilk heat-treated at $95^{\circ}C$/5 min and $120^{\circ}C$/10 min, respectively. 1. During the storage of soymilk yogurt, the concentrations of total solids, protein, fat, and lactose slightly decreased, whereas viscosity, content of ash and NPN, and the number of lactic acid bacteria remained unchanged. 2. The pH and titratable acidity changed rapidly in all soymilk yogurts after 3 h of incubation. 3. We found $7.8{\times}10^8$ lactic acid bacteria in the control sample, $4.7{\times}10^8$ and $5.02{\times}10^8$ in soymilk yogurt with skim milk, respectively, and $5.9{\times}10^8$ and $5.5{\times}10^8$, respectively in soymilk yogurt with whey powder according to degree of heat treatment with $95^{\circ}C$/5 min and $120^{\circ}C$/10 min. 4. The viscosity of yogurt samples became lower as the heat treatment increased in temperature and in the length of time. 5. The value of sensory evaluation was relatively high in soymilk yogurt with the added skim milk, which was heat-treated $95^{\circ}C$/5 min; however, the value was significantly lower than that of the control sample. 6. Lactose, glucose, and galactose were detected in all samples because lactose is degraded into glucose and galactose within 3 h of inoculation.

• 열처리공학회지
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• 제28권4호
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• pp.171-180
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• 2015

The variation in microstructure and texture during continuous annealing was examined in a series of 1.6% Mn-0.1% Cr-0.3% Mo-0.005% B steels with carbon contents in the range of 0.010 to 0.030%. It was found that microstructure of hot band consisted of ferrite and pearlite as a consequence of high coiling temperature, and eutectoid carbon content was between 0.011% and 0.016%. Martensite ranged in volume fraction from 1.5% to 4.0% when annealed at $820{\circ}C$ according to the typical continuous annealing cycle. The critical martensite content for the continuous yielding was about 4% from stress-strain curves. The continuous yielding was obtained in the 0.030% carbon steel and 0.010% to 0.020% carbon steels revealed some yield point elongation ranging from 0.8% to 2.2% in as-annealed conditions. Higher tensile strength in the higher carbon steel is due to both increase in the martensite volume fraction and ferrite grain refinement. Decreasing the carbon content to 0.01% strengthened the intensities of ${\gamma}$-fiber textures, resulting in the increase in the $r_m$ value, which was caused by the lower volume fraction of martensite. The higher carbon steels showed the lower $r_m$ value of about 1.0.

• KIEAE Journal
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• 제15권1호
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• pp.111-116
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• 2015

Heat loss from windows and condensation occuring on its surface due to its lower insulation value causes much discomfort to occupants. In this study, Heated glass was used to make a basic study on prevention of condensation on glass surface for its heating functionality through experimental measurement and simulation analysis of total heat flux on the interior and exterior surface of glass. Error between experimental results and three dimensional steady-state heat transfer analysis were caused firstly, beacuse in the experimental chambers, cold chamber and steady temperature and humidity chamber, air temperature setting was not constant but rather ON/OFF control, and secondly, due to error rate in heat flux meter due to heat flux direction even in stable conditions.

• 생약학회지
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• 제20권1호
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• pp.25-31
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• 1989

In order to establish the standard method for the preparation of processed Aconiti Tuber, Aconiti Tubers were processed under various conditions and the amount and the composition of alkaloids were determined by HPLC. The ratio of sum of benzoylhypaconine and benzoylmesaconine over the sum of acinitine, mesaconitine, benzoylmesaconine and benzoylhypaconine was used as a detoxification index ((BM+BH)${\times}$100/MA+AC+BM+BH). The adequate value of index was obtained from Japanese 'ka-gong bu-ja' which has been used in Japan. The processing procedure was largely devided into two categories. First is heat treating at $120^{\circ}$ and 1. 2 lbs for 60 min. Second is treatment with various kinds of alkaline solutions followed by heat treatment at $120^{\circ}$ and 1. 2 lbs for 60 min. Among the source of processed Aconiti Tubers, dried bu-ja and yom bu-ja, dried bu-ja was more adequate than yom bu-ja because yom bu-ja has the lower value of index than dried bu-ja and lost active components through the desalting periods. Dried bu-ja whish was treated with alkaline solutions followed by heat treatment has the detoxification index, 50% and dried bu-ja which was treated only with hear has 71. 8%. Compared to the value of index of Japanese 'ka-gong bu-ja', 72%, the dried bu-ja treated with heat at $120^{\circ}$ and 1, 2 lbs for 60min was the most adequate. The $LD_{50}$ value of the processed bu-ja was higher than 15 g crude drugs/kg, p.o. in mice.

• 한국응용과학기술학회지
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• 제32권3호
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• pp.394-404
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• 2015

This study investigated the pharmacodynamics of betaine on the blood profile and short chain fatty acid levels in meat ducks exposed to heat wave. 400 heads of Cherry valley (Anasplatyrhynchos) meat ducks were completely randomized to 5 treatments (4 repetitions each), and were raised for 42 days. They were grouped into T1 (heat wave control group without betaine), T2 (betaine 400 ppm), T3 (betaine 800 ppm), T4 (betaine 1200 ppm), and T5 (normal control group without betaine). Compared to T1, the betaine addition groups showed higher body weight gain at shipment, with T3 showing the highest significant difference. For hematological indictors measured (red blood cells and platelets), the betaine addition groups showed significantly higher values than the heat wave control group. The pH of the former was lower but their electrolytes ($K^+$, $P^+$, and $Cl^-$) were significantly higher compared to the latter. For blood gas concentration, the former showed a significantly higher value than the latter. For the total short chain fatty acids, acetic acid, and propionic acid, the betaine addition groups and group fed broiler-high temperature diet showed higher values than the heat wave control group. On the other hand, the former showed significantly lower values in butyric acid, isobutyric acid, valeric acid, and isovaleric acid than the latter group. These results suggest that betaine has the pharmacodynamics that mediate heat stress, via the maintenance and control of the blood profile, osmotic pressure, gas concentration, and short chain fatty acid, of meat ducks under heat wave.