• 환경위생공학
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• 제14권2호
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• pp.75-83
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• 1999

In this research, the has been speculation about effects of pH, alkalinity, and chloride, each of which are major factors in water for the corrosion of copper pipes frequently used as the distribution system throughout the world. It is believed that these factors release a corrosion by-product. The results show the following that the first, for each water sample of pH 7, 8 and 9, various concentrations of alkalinity at 10, 50, 100, 150 mg/L was tested. It was found that conditions of higher pH led to decreased concentrations of copper by-product. For each pH, higher alkalinity produced higher concentrations of copper by-product. the second, higher chloride concentrations led to decreased concentrations of copper by-product. Apparently this was due to the Nantokite(CuCl) formation on the inner walls of the copper pipes with the passage of time. The third, when 25, 50mg/L of chloride were added, the average decreasing rate of copper release concentration was 45.7, 66.7%, respectively.

• 대한기계학회논문집A
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• 제27권12호
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• pp.2072-2078
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• 2003

In this paper, the boundary element analysis of viscoelastic strain energy release rate G(t) for the cracked linear viscoelastic solids has been attempted. This study proposes the G(t) equation and the calculating method of G(t) by time-domain boundary element analysis for the viscoelastic solids. The G(t) is defined as the derivative of the viscoelastic potential energy II(t) with respect to crack length a. Two example problems are presented to show the applicability of the proposed method to the analysis of the cracked linear viscoelastic solids. Numerical results of example problems show the accuracy and effectiveness of the proposed method.

• 태양에너지
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• 제9권2호
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• pp.22-30
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• 1989

Since the energy storage method by means of the thermochemical reaction has no heat loss by separating the reactants under the storage period, it is remarked as one of promising means particularly for long-term heat storage. In this study, the heat-storage/-release characteristics of the reversible chemical reaction cycle, $Ca(OH)_2/CaO$, is numerically analysed by a mathematical modelling. As a result, the effectiveness of the heat exchanger by the chemical heat storage method is considerably higher than that by the sensible heat storage method. It is found that the major parameters, which determines the effectiveness of the heat exchanger, are the mass flow rate and inlet temperature of fluid, the residence time, etc.. The heat-storage/-release period can be controlled by changing the operation conditions. It is expected that the results obtained here will supply useful informations in designing a regenerative heat exchanger utilizing the thermochemical reaction.

• 약학회지
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• 제15권3_4호
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• pp.79-82
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• 1971

In order to compare the iron concentrations of the marketed ferruginous hematinics with the sustained-releasedosage forms and to prepare the good hemantinic which can be absorbed effectively without forming "iron block" in the gastrointestinal tract, gelatinized micropellets containing medicament were prepared and hardened in 10% formalin-isopropanol in the time of 72 hours. These micropellets were digested with artificial gastric juice and plotted a curve of released iron concentration. As a result, it is found that gelatinized micropellets sustained-release dosage form is an excellent ferruginous hemantinic and it is shown that several marketed preparations can be improved in their hemantinic actions by forming the sustained-release dosage.se dosage.

• PNF and Movement
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• 제16권1호
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• pp.1-6
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• 2018

Purpose: Myofascial release (MFR) is an effective treatment for improving muscle stiffness and balance in neurological patients. This study examined long-term effects of MFR on the balance ability of stroke patients. Methods: MFR using a tennis ball was applied to the lower extremity and sacroiliac joint of the affected side of four stroke patients. The four subjects performed the Berg balance scale (BBS) and Timed up and go (TUG) test at the beginning of an 8-week intervention, directly after the intervention, and 2 years later. Results: The BBS scores indicated a trend toward maintenance of balance (p=0.05), but there was no difference in the TUG time (p=0.47). Conclusion: MFR may be a clinically meaningful intervention to maintain balance in stroke patients over a long period. However, the sample size in this study was too small to draw general conclusions. A larger study with more participants is needed.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.716-717
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• 2006

Gas release behavior from aluminum and Al 7075 alloy powders during heating in argon was investigated by in-situ gas chromatography. Water vapor, hydrogen, carbon mono-oxide were detected as individual evolution spectra against heating temperature and time. The mechanisms of water and hydrogen evolutions were studied in detail for the determination of effective degassing condition. Magnesium in the alloy powder was found to lower the hydrogen evolution temperature to enhance overall hydrogen release.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 추계학술대회
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• pp.87-88
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• 2014

The Coastal sediment is highly contaminated due to ship transportation, industries discharges and urban sources. Various contaminants release into seawater and settle in marine sediment and it significantly affect marine eco system. In the present study evaluated the optimization of slow release biostimulant ball (BSB) in coastal sediment in busan. The effective variables like BSB size, distance and month variables on VS reduction was determined by using Response surface methodology(RSM). The analysis of variance (ANOVA) and coefficient determination (R2) of VS was 0.9369 and maximum reduction of VS was obtained in 3cm ball size and 5.5cm distance and 4 month interval time. This result revealed that the BSB in effective VS reduction in coastal sediment.

• International Journal of Industrial Entomology and Biomaterials
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• 제27권2호
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• pp.312-316
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• 2013

Caffeine is a thermogenic agent that can be used in weight loss products. In order to achieve a sustained release of caffeine, silk fibroin (SF) film was uses as carrier. It has been shown that the loading method of caffeine into SF film affected the uniform distribution of caffeine in the SF film. When caffeine was added directly into SF solution, gelation has been occurred immediately and prevented the uniform distribution of caffeine. On the other hand, caffeine was dissolved in methanol in order to load the caffeine in SF film and crystallize the SF film at the same time. However, due to the fast evaporation of methanol, caffeine was recrystallized on the surface of SF film rather than penetrating into the film. Finally, caffeine was loaded into pre-crystallized SF film and uniform distribution of caffeine could be achieved. There was an initial burst of caffeine during the first 15 min, but after that a sustained release was achieved.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2013년도 추계학술대회 초록집
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• pp.178-179
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• 2013

본 연구에서는 현재 사용되고 있는 건축물 내의 화장실 칸막이 재료를 대상으로 ISO 5660-1 콘칼로리미터(Cone calorimeter) 실험을 실시하여 대상 실험 재료들의 연소 특성을 비교 평가 하였다. 모두 5종류의 실험체를 사용하였으며, 화재 발생시 연소 중요 평가항목인 착화시간(Time to ignition), 총 방출열량(Total heat release), 최고 열방출율(Peak heat release rate), 평균 열방출율(Mean heat release rate)을 중점적으로 평가하였다. 실험결과, 착화시간은 일반 합판패널에서 빠르게 일어났으며, 총 방출열량, 최고 열방출율, 평균 열방출율은 고밀도 압축패널에서 높게 나타난 것으로 분석되었다.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.77-84
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• 1997

Cone calorimeter measurements can be used for the calculation of effective material properties, which can be used as input parameters in modeling of fire. Main parameter measured in Cone calorimeter is heat release rate. Some other parameters as time to ignition, effective heat of combustion, mass loss rate or total heat released is also measured in Cone calorimeter. Total heat released is important from the point of view of total energy available in material in Fire situation. Cone calorimeter. measurements were done on several wood species (oak, beech, spruce, poplar). Measurements were provided at external irradiances 30, 50 and 65 ㎾/$m_2$ in horizontal orientation. Heat release rate data were evaluated and compared as a function of external irradiance for various species of wood. furthermore the influence of external irradiance on effective heat of combustion and total heat release was also evaluated for the period of flame combustion.