• 한국농공학회지
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• 제26권3호
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• pp.46-58
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• 1984

This study was carried out to investigate the compressive strength and the other effects varying to seasons and curing days on the wet curing conditions of the plain concrete. The results obtained are summarized as follows; 1. The longer the wet curing days and the higher the temperature, the greater the compressive strength was expected. 2.。$_2$8, compressive strength of concrete at 28 days under the dry curing conditions showed a range in 64-76% of that under the wet curing conditions. 3. The seasonal variations in the compressive strength under the wet curing showed in order of summer>spring=autumn>winter, and that under the dry curing were in order of spring ≒autumn> summer> winter. 4. In order to obtain 90% of the design compressive strength, 7 days in spring or autumn and 2 weeks of the wet curing in summer were required. 5. The compressive strength of concrete under the wet curing by using wet straw bag cover was almost the same as that of water curing method. 6. Under the wet curing conditions, the higher the temperature, the greater the effect of the curing of concrete was obtained, however, the compressive strength of concrete was decreased under relatively higher (over 15$^{\circ}$ C) and lower temperature (below 4$^{\circ}$C). 7. Freezing damage was occured when temperature was below 0$^{\circ}$ C and humidity was relatively high. 8. A considerable differnce between estimation of $^{\circ}$$_2$8 from $^{\circ}$7 and measured one was appeared in case of the dry curing conditions. Oregon formula was appeared to be acceptable under the wet curing conditions. 9. In relationship between $^{\circ}$$_2$8 and $^{\circ}$7~, $^{\circ}$28=1. 52 $^{\circ}$7 under the wet curing conditions except winter season, and $^{\circ}$$_2$8 =(1.39-1, 48)$^{\circ}$7 under the dry curing conditions were shown.

• Animal Bioscience
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• 제34권10호
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• pp.1705-1716
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• 2021

Objective: This study aimed to elucidate the effects of cooking conditions on the physicochemical and sensory characteristics of dry- and wet-aged beef strip loins. Methods: Dry- and wet-aged beef aged for 28 days were cooked using different cooking methods (grilling or oven roasting)×cooking temperatures (150℃ or 230℃), and their pH, 2-thiobarbituric acid reactive substances (TBARS), volatile compounds, and color were measured. Results: Cooking conditions did not affect pH; however, grilling resulted in lower TBARS but higher cooking doneness at the dry-aged beef surface compared to oven roasting (p<0.05). In descriptive sensory analysis, the roasted flavor of dry-aged beef was significantly stronger when grill-cooked compared to oven roasting. Dry-aged beef grill-cooked at 150℃ presented a higher intensity of cheesy flavor, and that grilled at 230℃ showed a greater intensity of roasted flavor compared to wet-aged beef at the same condition, respectively. Conclusion: Grilling may be effective for enhancing the unique flavor in dry-aged beef.

• Current Optics and Photonics
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• 제3권5호
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• pp.423-428
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• 2019

Visibility of road-surface markings is one of the critical issues that should be secured for self-driving cars as well as human drivers. Glass beads are taking on the role of retroreflectors, and therefore are considered a necessity in modern pavements. In this context, retroreflectance is sensitively dependent not only on the refractive index of glass beads but also on that of the surrounding medium. This implies that the optimum refractive index of glass beads immersed in water, i.e. under wet conditions, is different from that of glass beads surrounded by air, i.e. under dry conditions. A refractive index of approximately 1.9, which is known to maximize retroreflectance under dry conditions, actually exhibits much poorer retroreflectance under wet conditions. This suggests that glass beads with optimal refractive index for wet conditions need to be installed together with those for dry conditions. We propose a facile but practical model capable of calculating retroreflectance of glass beads surrounded by an arbitrary medium, here water in particular, and experimentally verify its capability of assessing the refractive index of commercial glass beads. Changes in retroreflectance according to the mixing ratio of glass beads with different refractive indices are also discussed, in an effort to propose the proper use of glass beads produced for dry and wet conditions.

• 한국생활환경학회지
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• 제24권1호
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• pp.95-106
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• 2017

The purpose of this study was to evaluate comfort functions while wearing firefighters' protective gloves in dry and wet conditions at $70^{\circ}C$ air temperature with radiant heat. Four types of firefighting gloves from Korea, Germany, United States, and Japan were evaluated in both dry and wet conditions by eight male firefighters. Firefighters put their hands and forearms wearing gloves into a hands-radiant chamber that maintained at an air temperature of $70{\pm}2^{\circ}C$ ($T_a$) and globe temperature $106^{\circ}C$ ($T_g$). During the exposure, subjects followed a fixed protocol of manual movements and stopped the exposure when they felt being intolerable. Results showed that completion time was extended by 6 min on average when gloves got wet and 15 min for the Japanese gloves was extended when compared to its dry condition (p<.001); microclimate humidity on the palm at the last stage was greater for wet conditions than dry conditions in the all gloves; and skin temperatures on mid-fingertip, palm, and hand were significantly lower for wet conditions than dry conditions especially for Japanese gloves (p<.001). These results indicate that the exposure time without thermal pain to radiant heat could be extended by wetting gloves during the low radiant heat exposure.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권3호
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• pp.128-137
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• 2005

In this study, dry and wet surface pressure drop and heat transfer characteristics of heat exchangers having plain fins were investigated. Nine samples having different fin pitches and rows were tested. The wet surface heat transfer coefficient was reduced from experimental data using enthalpy-potential method. The wet surface heat transfer coefficients were approximately equal to the dry surface values except for one row configuration. For one row configuration, the wet surface heat transfer coefficients were approximately $30\%$ lower than the dry surface values. For the pressure drop, the wet surface yielded approximately $30\%$ higher values compared with the dry surface counterpart. Data were compared with existing correlations.

• 설비공학논문집
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• 제16권3호
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• pp.218-229
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• 2004

In this study, dry and wet surface pressure drop and heat transfer characteristics of heat exchangers having plain fins were investigated. Nine samples having different fin pitches and rows were tested. The wet surface heat transfer coefficient was reduced from experimental data using enthalpy-potential method. The wet surface heat transfer coefficients were approximately equal to the dry surface values except for one row configuration. For one row configuration, the wet surface heat transfer coefficients were approximately 30% lower than the dry surface values. For the pressure drop, the wet surface yielded approximately 30% higher values compared with the dry surface counterpart. Data were compared with existing correlations.

• 생명과학회지
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• 제9권4호
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• pp.368-374
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• 1999

Three soybean cultivars, Hwangkeum, Tanyeob and Enrei were planted in the same pot under glasshouse conditions to investigate the influence of the different soil water content such as pF 1.4(wet), 2.1(control) and 3.6(dry) on the transpiration rate, dry matter production and water requirement. The transpiration rate remained the high constant rates under the wet soil condition and the control than the dry condition, and showed a linear correlation between transpiration rate and solar radiation under the all condition of soil water. The transpiration rate highly increased in the morning, but dramatically decreased in the other time in a day. The dry matter production was higher under the conditions of wet soil and the control than that under the dry condition. Also, the dry matter production Tanyeob was higher than other cultivars under all soil water content. The water requirement was higher for Enrei and lower Tanyeob than the control.

• 한국산업융합학회 논문집
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• 제22권3호
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• pp.243-250
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• 2019

The nanosecond laser assisted ablation have been investigated. The biocompatable polymer PMMA was employed as the target material and the two distinctive surface conditions were test. The first surface condition is a dry surface for which the target surface is exposed to air and the second surface condition is the wet surface for which the target surface is covered with dehydrated water. The ablation volume, the laser induced acoustic wave, the laser induced plasma were investigated for both wet and dry condition. The nanosecond laser pulse ablatied more on the wet surface compared to the dry surface. The enhanced ablation of wet surface is attributed to the confined acoustic wave and the laser-induced plasma in the liquid layer.

• 수산해양기술연구
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• 제29권2호
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• pp.117-123
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• 1993

In order to analysis the tensile properties of the high-tech fibers for fishing gear materials. tensile strength was tested on raw materials, single yarns and netting twines(plied yarns)made of nylon, kevlar 29 and techmilon respectively. The results obtained are as follows: 1. The tensile stress and tenacity of unknotted single yarns in dry and wet conditions were 3 to 3.5 times greater in the high-tech fibers than in nylon. But the elongation of the high-tech fibers was about 15% of that in nylon. 2. The tensile strength of knotted single yarns in dry and wet conditions was arranged in order of as follows : techmilon. kelver 29, and nylon. The ratio of knot strength to tensile strength, knot efficiency, was the highest in nylon. 3. The tensile strength of unknotted netting twines in dry and wet conditions was 2.3 to 2.5 times greater in the high-tech fibers than in nylon. 4. The tensile strength of knotted netting twines in dry and wet conditions was arranged in order of as follows : techmilon, kevlar 29, nylon. The knot efficiency was the highest in nylon.

• 한국정밀공학회지
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• 제33권7호
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• pp.541-549
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• 2016

Rolling contact fatigue and wear on rails are inevitable in railway operations due to excessive wheel-rail contact stress. The wear is influenced by vehicle speed, contact pressure, environmental conditions, and many other factors. Speeding on a curved track causes many problems such as wear on the gauge of the rail and rolling contact fatigue. Managing environmental conditions can reduce problems on the wheel and rail interface. In this study, the wear characteristics of wheel and rail materials were investigated by twin-disc testing using various parameters. The results of the wear test indicated that the wear rate under dry conditions was larger than that under wet conditions. We found that contact fatigue damage occurred on the rail in dry conditions, however, the surface of the specimen under water remained smooth. Also, the friction coefficient in dry conditions was larger than in wet conditions.