• Journal of Advanced Marine Engineering and Technology
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• v.31 no.8
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• pp.939-946
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• 2007

The purpose of this study is to measure and analyze the ship's indoor thermal conditions and also to integrate experimental database of those, supplied and controlled by ship's HVAC. On this study, temperature, humidity and air volume of 6 different needs' cabin are measured on a newly-launched training ship during 2nd through 5th of April, 2007. Followings are the results of this study. (1)Because only partial loads are needed in spring season, the air volume from diffusers are measured as below 20%. (2)The temperatures are ranged between $20{\sim}25^{\circ}C$ and those are within comfort temperature range proposed by AHREA. (3)But humidities in cabins are very low and it could be the reason of a cold and/or a skin disease. (4)From the student cabins' measurements which have different supply diffuser(s), it is clear that the design is suitable for this case. (5)Because of low humidity, only 16.1% among the measured data are satisfied with the comfort standard range proposed by ASHREA. To improve the predictability and the comfort, HVAC should maintain the humidity as $40{\sim}60%$.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.35-38
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• 2003

The purpose of this study is to investigate the manufacture of light weight concrete panel using the artificial light-weight aggregate as a part of the substitution of foamed styrene and polyurethane because of narrow allocable temperature Bone in use. The experimental parameter of this study is 40, 60 and 8$0^{\circ}C$ of curing temperature at 100% relative humidity and the type of admixture such as cement, 6mm glass fiber and St/BA emulsion. Testing item is compressive and flexural strength and strength of specimen cured at standard condition is compared to that of specimen cured at 40, 60 and 8$0^{\circ}C$ of curing temperature at 100% relative humidity. As a result or this, it was revealed that the maximum or strength is developed in 6$0^{\circ}C$ or cure temperature at 100% relative humidity in case of the most of the specimen. Specimens modified by St/BA emulsion show the highest development of strength dependent on the curing tmeperature. So, it seems to be effective that evaporation curing method shoud be considered to curing the specimen as the panel core.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.1
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• pp.61-74
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• 2011

Critical environmental elements for long term preservation of a paper are temperature, humidity, dust, light, contaminants in air, and mold. Especially, temperature and humidity need special care, because they can not only directly degrade paper but also affect the degradation of the other elements. Therefore methods to monitor variation of temperature and relative humidity were studied. One of the methods was to use preservation index for evaluating preservation environment. Since the evaluation for preservation environment of a stack room investigated firstly by D. K. Sebera, PI(preservation index) and TWPI(Time-Weighted Preservation Index) by IPI is made to evaluate relatively preservation environment in a stack room. T. Padfield developed method which could calculate easy PI and TWPI. In this study, the preservation environment of stack rooms for paper storage in NAK(National Archives Korea) was evaluated by PI and TWPI. PI and TWPI of stack rooms for paper storage in NAK maintained good condition but PI depended on season. Then the preservation environment of stack rooms for paper storage in NAK was required to maintain continuously PI and TWPI regardless of season change.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.739-744
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• 2018

In this study, effects of reducing white smoke at a heat exchange system for white smoke reduction were studied in the winter season. For this purpose, the heat transfer processes on the exhaust air were investigated by Solidworks. Five wave heat exchangers of air-to-air and air-to-water type were applied for the exhaust air heat recovery. The analytical condition of the exhaust air was fixed and the computational analysis was performed according to the change of SA(supply air) inlet velocities. In order to evaluate the performance of the heat exchange system for white smoke reduction, W(water)/SA recovered capacities and the temperature/absolute humidity reduction rate were calculated. As SA inlet velocity increased, the exit temperature and absolute humidity of the mixing zone were reduced by up to about $40^{\circ}C$ and 0.12kg/kg respectively. Also, W/SA recovered capacities increased linearly up to about 35%.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.277-282
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• 2016

This study was aimed to investigate the effect of air-circulation fans on air temperature and relative humidity in a single-span tomato greenhouse (W: 7m, L: 25m, H: 3.2m). According to standard of fan layout by ASAE (1997), a total of 10 fans were bilaterally arranged in 2 rows in the experimental greenhouse. The distributions of air temperature and relative humidity were measured from 6 pm to 8 am under different conditions, with and without fans. The measurement heights were 0.7m, 1.7m and 2.7m. Under the condition of "fans off", the spatial differences of air temperature and relative humidity between upper and lower sides were $1.7^{\circ}C$ and 10.8%, respectively. The operation of 10 fans showed their differences to $0.1^{\circ}C$ and 3.2%. The number of fans and installation direction were evaluated their performance on reducing the spatial variation of air temperature and relative humidity. The experimental layouts were 5 and fans in 2 rows (bilaterally) and 10 fans in the one (same) direction. Under the condition of "6 fans on" and "5 fans on", the spatial differences of air temperature and relative humidity between upper and lower side were $0.3^{\circ}C$, 3.4% and $0.3^{\circ}C$ and 4.0%. The operation of 10 fans in the one direction reduced their differences to $0.5^{\circ}C$ and 4.9%. The overall findings of this study showed that there was no significant differences under each condition. Therefore, this study suggested that it is more economic and effective to install five fans in 2 rows (bilaterally) in the greenhouse (W: 7m, L: 25m, H: 3.2m).

• Proceedings of the KIEE Conference
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• 2008.04b
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• pp.131-133
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• 2008

This study presents on the analysis fire hazards of drum type electric washing machine. In order to analyze fire hazards fire experiment is conducted. The fire experiment is conducted to simulate under the normal condition and abnormal condition. The experiment under the abnormal condition is simulated in safety device failure, situation of accumulated dust and tracking phenomenon caused by humidity. The results show that fire hazard is high at the abnormal condition. In this paper, we suggest to use the safety device of low operating temperature in electric washing machine for reducing fire hazard.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.3
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• pp.328-331
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• 2008

This study presents on the analysis fire hazards of drum type electric washing machine. In order to analyze fire hazards fire experiment is conducted. The fire experiment is conducted to simulate under the normal condition and abnormal condition. The experiment under the abnormal condition is simulated in safety device failure, situation of accumulated dust and tracking phenomenon caused by humidity. The results show that fire hazard is high at the abnormal condition. In this paper, we suggest to use the safety device of low operating temperature in electric washing machine for reducing fire hazard.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.4
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• pp.54-61
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• 2023

In this paper, the compressive strength, pore characteristics, and chloride diffusion coefficient were measured at 28 days of age in order to examine the influence of curing conditions for the chloride diffusion and pores in concrete cured under extreme condition. According to the test results, the compressive strength was improved as the relative humidity increased. Additionally, higher compressive strength was observed when the specimens were cured at 35℃. However, the compressive strength of specimens cured at 45℃ was decreased. Meanwhile, the chloride diffusion coefficient decreased with an increase in curing temperature and relative humidity, indicating a difference compared to the trend observed for compressive strength. On the other hand, the excellent correlation showed between compressive strength and chloride diffusion coefficient, porosity and chloride diffusion coefficient when the concrete cured under water. However, when the concrete cured under extreme condition, this correlation was significantly reduced compared to the water curing case. In contrast, it has been determined that there is no significant correlation between the average pore size and chloride diffusion coefficient, regardless of the curing conditions.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.232-236
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• 2001

Four air temperature levels of 23, 25, 27 and 29$^{\circ}C$, three humidity levels of 85, 90 and 95% R.H. at photosynthetic photon flux (PPF) of 50 $\mu$mol.m$^{-2}$ .s$^{-1}$ were provided to investigate the effect of vapor pressure deficit on the evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seed-increase. Thus EVTR of grafted seedlings increased with increasing air temperature at high humidity of 95%R.H. At relatively low humidity of 85% R.H., grafted seedlings showed a high EVTR and some wilting of scions was observed at this condition. This result would be ascribed to the low supply of water to vascular bundles according to the insufficient joining of scions and rootstocks. Differences in EVTR between 90% R.H. and 95% R.H. were not observed. Grafted seedlings showed high graft-taking at high relative humidity. Relative humidity had highly influenced to the graft-taking as compared to the air temperature. Graft-taking increased with decreasing vapor pressure deficit. Graft-taking greater than 90% was found at vapor pressure deficit less than 0.4kPa which could be obtained at humidity higher than 90% R.H. Therefore it is required to control the humidity higher than 90% R.H. for suppressing EVTR of grafted seedlings and preventing some wilting of scoins and thus enhancing the graft-taking of grafted seedlings.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.6
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• pp.1021-1030
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• 1997

Physical variables related to the subjective evaluation of wear comfort were explored. Experimental fabrics was those used in the previous paper where subjective sensations of women's thin shirts were reported. Fabrics include 100% cotton (unfinished), 100% cotton (water repellent finished), cotton/polyester 35/65 (unfinished), cotton/polyester 35/65 (peach skin finished), 100% polyester fabric(plain), 100% polyester crepe. Among various physical properties of the experimental fabrics, heat 8E moisture transport properties and surface properties were chosen as important variables based on the regression coefficient. Especially, humidity at the microclimate in dynamic mode was highly correlated to the subjective evaluation and appeared to be a sensitive physical predictor, compared to dry thermal transmission rate or water vapor transmission rate. Surface characteristic parameters, however, did not show consistant trend in the prediction of the human's subjective sensation. Interaction between surface properties and humidity measurement was also observed.