• Science of Emotion and Sensibility
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• v.3 no.2
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• pp.75-84
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• 2000

문명의 발달과 함께 수면부족으로 인한 여러 가지 스트레스와 질환이 증가하게 되어 최근 수면연구에 대한 관심이 증가하고 있다. 본 연구는 다양한 온열환경 조건에서의 쾌적한 수면을 위한 온열환경을 제시하기 위해, 5명의 여성 피험자를 대상으로 22$^{\circ}C$, 26$^{\circ}C$, 3$0^{\circ}C$의 일정온도 조건과 $25^{\circ}C$에서 1시간 후와 2시간 후에 각각 1, 2$^{\circ}C$를 상승시켜주는 변동온도 조건하에서 수면생리신호를 측정하였다. 그리고, 수면단계 평가를 이용하여 총 수면시간, 깊은 수면의 비율, 그리고 최초 수면시작 시간에서 최초의 서파 수면이 나타나기까지의 지연시간 등의 수면효율을 평가하였다. 그 결과, 일정온도 조건에서는 26$^{\circ}C$에서 총 수면시간(466.7$\pm$10.25분)과 깊은 수면의 비율(33.1$\pm$4.95%)은 타 조건에 비해 높게 나타났고, 최초 서파수면까지의 지연시간(9.8$\pm$3.33분)은 타 조건에 비해 낮게 나타나 쾌적한 수면을 위한 가장 적절한 온열조건임을 관찰할 수 있었다. 그리고 변동온도 조건에서는 4가지 온열조건간에는 큰 차이가 나타나지 않았지만, 모든 조건에서 일정온도 조건보다는 좋은 결과를 나타내었다. 또한 수면 중 신체 움직임과 설문 분석에서도 동일한 결과를 보였다. 본 연구를 통해, 수면생리신호를 이용한 수면 쾌적성 분석은 수면의 질적인 상태를 관찰하는데 매우 적합한 파라메터를 도출할 수 있으며, 여러 가지 수면환경 조건을 평가하는데 매우 유용한 지표가 될 수 있음을 보였다.e results suggest that hCG treatment at 7 days after insemination could be used to increase the pregnancy rate of embryo transfer, and transfer, and only the recipients with PUN concentration of <12 mg/dl were influenced by treatment with hCG./TEX>이었으며, 이는 화성 기원을 지시한다.sucrose를 이용한 2단계 희석이 수정란의 생존성을 향상시키는 것으로 나타났다. 또한 발육 단계별 생존성에 있어서는 발육이 진전된 확장배 반포 시에 동결하는 것이 배반포기에 동결하는 것 보다 유리한 것으로 나타났다.ody를 사용하여 flow cytometery해석을 실시하는 한편 125I-hGH binding assay에 의하여 hGH binding activity를 측정하였다. 최종적으로 GH signal transduction의 target genedf으로 알려져 있는 serine protease inhibitor 2.1(Spi 2.1) gene의 promotor activity를 검토한 결과 hGHR을 transfect한 CHO Cell에 있어서 hGH의 농도에 의존적으로 증가되었다. 따라서 본 실험에서 cloning한 cDNA hGHR는 native hGHR와 같은 기능을 가지는 것으로 판명되었다.것으로 판명되었다..ments of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.353-358
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• 1985

Three kinds of aqueous solution of tobacco extracts are used as a new experimental material. It is measured how the operating condition, freezing point, viscosity as fundamental properties have the relation to concentration and temperature of the solution. The results of this study are obtained as follows. 1) The freezing point of the solution $(t_m)$ is presented; $t_m=-{\frac{18.6X}{170-{\frac{X}{100}}(170+18)}}$ 2) The correlation of the viscosity, the temperature and the concentration of the solution is followed; $log_{10{\mu}}={\frac{1585}{T}}+2.11{\frac{X}{100-X}}-5.50$ 3) The ice crystals whose circumference is a toothed wheel are made from high concentrated solution, and the thick plate shaped ones are done from the low concentrated solution.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.459-464
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• 2002

This experiment was conducted to know the changes of bioactive component content in four-year-old peony (Paeonia lactiflora Pall.) root with various drying methods such as room temperature drying, $50^{\circ}C$ heat-air drying, room temperature drying after $80^{\circ}C$ boiling water treatment and freeze drying, and to establish the optimum drying method for high quality production of Paeoniae Radix. For this purpose, the contents of paeoniflorin, albiflorin and five phenolic compounds (gallic acid, benzoic acid, (+)-catechin, (-)-epicatechin and (+)-taxifolin 3-O-$\beta$-D-glucopyranoside) in peony root with different drying methods were analyzed by RP-HPLC. The contents of paeoniflorin, albiflorin and (+)-taxifolin 3-O-$\beta$-D-glucopyranoside at room temperature drying were higher than in the other drying methods and that of gallic acid at 8$0^{\circ}C$ boiling water treatment was the highest among that of all drying methods. In the case of freeze drying, the contents of (+)-catechin, benzoic acid and (-)-epicatechin were the highest among those of all drying methods. As increase of drying and treatment temperature, the contents of paeoniflorin, albiflorin, (+)-taxifolin 3-O-$\beta$-D-glucopyrano-side, (+)-catechin and benzoic acid were decreased.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.1
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• pp.49-58
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• 2017

The phenomena that we experience in everyday life such as snow, rain, wind, and temperature are referred to as weather, and the average state of atmospheric phenomena that occur over a long period of time in a specific region is referred to as climate. In addition, significant variation of climate compared to the average state is referred to as climate change. Concrete structures can have various problems when exposed to elements. Among the problems, the freeze-thaw problem due to extreme climatic factors such as heavy rain and snowfall has become a particularly significant issue recently. The concrete that has been subjected to repeated freeze-thaw rather than too high or low temperature shows serious degradation of durability, and the performance of structures with degraded performance is difficult to recover. Therefore, in this study, concrete durability performance with respect to freeze-thaw from curing conditions change due to wind speed and sunshine exposure time. Concrete freeze-thaw experiment are performed. using wind speed and sunlight exposure time. Also, performance based evaluation through the satisfaction curve based on the freeze-thaw test results are performed.

• Tunnel and Underground Space
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• v.25 no.5
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• pp.435-449
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• 2015

Physical and microstructural properties of Pungchon and Maggol limestone were investigated quantitatively during 50 cycles of artificial freezing and thawing test. There were decrease in dry weight and P,S-wave velocity, and increase in absorption rate in both rock types. Porosity, pore volume, equivalent diameter, throat thickness and pore orientation were analyzed using X-ray computed tomography images. Porosity increased, and initiation and expansion of pores were investigated as weathering progresses. Physical and microstructural variation in Maggol limestone was larger than that of Pungchon limestone because Maggol limestone has more pores and microcracks at initial state. As this study analyzes physical and microstructural properties of rock specimens comprehensively, it can be applied to further rock weathering study and can be used as fundamental data of construction and resource development in cold regions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.909-916
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• 2013

Concrete containing lightly burnt MgO has long term expansibility. It also could compensate for the thermal shrinkage of mass concrete, because the hydration of MgO proceeds at a slow pace to long-term age. Thus, lightly burnt MgO has been applied to the construction of mass concrete such as dams. Recently, the expansion characteristics of MgO concrete with fly ash that could be applied to mass concrete for the reduction of hydration heat have been studied and however, limited studies on its durability. This study investigates the long-term durability characteristics of fly ash concrete with lightly burnt MgO. The durability tests on carbonation, freezing-thawing, diffusion of chloride, and resistance to sulfate attack were carried out for MgO concrete with curing for 360 days in submerged condition with different temperature of 20 and $50^{\circ}C$. The results reveal that MgO concrete shows a greater resistance of carbonation, diffusion of chloride, and resistance to sulfate attack. On the other hand the resistance of freezing-thawing was little influenced by MgO powder.

• Journal of the Korean Geosynthetics Society
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• v.9 no.3
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• pp.39-45
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• 2010

When the ground temperature drops below $0^{\circ}C$, wet soils expand due to the ice formation in their porous space. This results in frost heave which causes structural stability problems. Frost heave is attributed by several factors such as physical soil properties and heat transfer including pore water phase change. Due to the complex physical phenomena, reliable and verified multi-dimensional numerical models for frost heave problems are still in a research stage. This study presents an efficient and simple method of overcoming numerical problems associated with sudden jump of heat capacity due to the phase change from water to ice in the pore space. This paper proposes heat transfer equation and finite element method when the saturated soils or porous rocks are subjected to freezing. Numerical analyses using the proposed method agree well with the known closed form solution and the laboratory test results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1094-1097
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• 2007

Vibration at frequency of 20 Hz and 0.18 g of acceleration was applied to 600 g watery kimchi contained in a glass jar of 1 L at subfreezing temperature (-3 and $-6^{\circ}C$) and $10^{\circ}C$ in order to see its effect on freezing and fermentation behaviors, respectively. The vibration at the subfreezing temperature delayed the freezing process and contributed to maintaining small ice crystal slurry in subsequent frozen storage. The vibration at $10^{\circ}C$ accelerated the acid and carbon dioxide production from the watery kimchi, which may be beneficial in shortening ripening time and attaining fresh cool taste.

• Food Science and Preservation
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• v.14 no.5
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• pp.462-468
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• 2007

In this study, the quality effect of soaking in alum water, soaking in electrolyzed oxidizing water, and freezing during storage, on peeled chestnuts, were analyzed. When soaked in 0.1% (w/v) alum water, peeled chestnuts showed good characteristics in terms of weight loss, decomposition, and color preservation. However, texture and taste qualities rapidly decreased with increases in storage time. When soaked in twice their own weight of electrolyzed oxidizing water(pH 2.61, ORP 1,142 mV) for 10 min, the samples were preserved in an optimally edible condition. When frozen at $-10^{\circ}C$ for 5 min, the samples were suitable for use as material for processed chestnut produce, as was also the case when pretreatment with electrolyzed oxidizing water was employed.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.593-596
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• 2008

Domestic area of most be happened chloride deicer damage. Because daily mean temperature is below 0$^{\circ}C$ from the area of domestic most. Use of deicing chemicals has been and will continue to be a major part of concrete structure in the highway. Chloride-containing chemicals such as calcium chloride or rock salt are main deicers for the road. Extensive use of chloride deicers is, however, not only the source of substantial cost penalties due to their corrosive action and ability to deterioration roadway surface materials but also the source of environmental damages. Chloride-containing chemicals such as calcium chloride or rock salt are main deicers for the road. Extensive use of chloride deicers is, however, not only the source of substantial cost penalties due to their corrosive action and ability to deterioration roadway surface materials but also the source of environmental damages. In this study, Use of deicing chemicals has been and will continue to be a major part of highway freeze-thaw durability and carbonation of concrete surface protecting materials