• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.63-69
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• 1983

The tensile strength (Pm) . elongation percentage ($\varepsilon$) , elastic modulus (I) , and specific volume (Sv) were calculated from the data of tensile characteristics of By 104 .and Burley 21 tobacco leaves, which were measured over a relative humidity from 60 to 80% at $20\pm2^{\circ}C$.The important results obtained were as follows.(1) Tensile strength(Pm) The "Pm"of By 104 was greater than that of Burley at. The "Pm"in both varieties were increased toward the upper stalk position and according to the decrease of relative humidity. The "Pm" of parallel piece to tile vein in a leaf were greater than that of right angle piece to the vein. (2) Elongation percentage ($\varepsilon$). The "s" of By 104 was higher than that of Burley 21. The "s" in both varieties were increased toward the upper stalk position and according to the increase of relative humidity. The "s" of parallel Piece to the vein in a Burley leaf was greater than that of right angle piece to the vein. (3) Elastic modulus (E) The "E" of Burley 21 leaf was higher than that of By 104. The "E" in both varieties were increased toward the lower stalk position and according to decrease of relative humidity. The "E"of parallel piece to the vein in both varieties leaves were greater than that of right angle piece to tile vein. (4) Specific volume (Sv) The "Sv" of Burley 21 leaf was increased than that of By 104. The "Sv" in both varieties were increased toward the lower stalk position and according to the decrease of relative humidity.ot;Sv" in both varieties were increased toward the lower stalk position and according to the decrease of relative humidity.dity.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.437-442
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• 1984

The color changes and sorption characteristics of dried whole red pepper stored at various relative humidity and temperature were studied. Dried whole red pepper was browned at relative humidity above 67%, and was molded at relative humidity above 84%, and was decolorated at relative humidity below 32%. Therefore, about 50% RH condition was suitable for the preservation of dried whole red pepper and the safe moisture content levels for storge to prevent decolorization were ranging from 15.65% to 19.62% dry basis (DB) with varying temperatures. The moisture contents of monolayer value for the dried whole red pepper were ranging from 7.52% to 9.23% (DB) with varying temperatures. The third order regression equation for the equilibrium moisture content prediction with relative humidity was determined.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.176-180
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• 1987

The sorption characteristics of dried garlic flakes stored at various relative humidity and storage temperature were studied. At low relative humidity below RH 51%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 67%, the flakes were browned by higher equilibrium moisture content. The flakes were browned at relative humidity above 67% at $20^{\circ}C$ and $35^{\circ}C$, above 84% at $5^{\circ}C$, respectively. The moisture contents of monolayer value for the flakes were ranging from 5.80% to 6.20% (DB) with varying temperatures. And the necessity of moisture-proof packaging material suggested for the long term storage of the flakes because the lower moisture content and storage temperature, the higher driving force of wetting. Regression equation for browning rate prediction with relative humidity and storage temperature of the flakes was determined.

• Journal of Mushroom
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• v.16 no.4
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• pp.263-266
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• 2018

This study was investigated the growth characteristics of 'Nongjingo' cultivar(Lentinula edodes) according to relative humidity(RH). The color difference of the pileus showed the highest L(Lightness, L) value in RH65 and the a(Redness, a) value in RH95. b(Yellowness, b) values were similar in all treatments. The hardness of pileus is highest at RH95. As the relative humidity increased, the length of pileus and stipe tended to increase. The diameter and thickness of pileus were high at RH95%. The diameter of stipe could not see the big difference in the three treatment groups. This study growth characteristics and yield were increased at higher relative humidity, but quality was decreased. Therefore, must adjust the relative humidity to produce high quality mushrooms.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.2 s.120
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• pp.38-44
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• 2007

The hygroscopic property of paper is important for convertability and end use performance. When the board and corrugated fiberboard are exposed to low relative humidity, a trouble of score (or crease) cracking could occur. In this study, we evaluated the moisture content and mechanical properties of linerboard and corrugated board at the cyclic condition of low humidity to prevent a score crack trouble. As the relative humidity decreased from 50% to 38% and 25%, the moisture content of linerboard decreased about 7% to 6% and 4%. At low humidity, most of mechanical properties were improved except for strain. The linerboard exposed at 25% RH showed a remarkable reduction of strain by 11%. At the same relative humidity, linerboard and corrugated fiberboard showed the different property values depending on moisture hysteresis.

• Applied Science and Convergence Technology
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• v.25 no.6
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• pp.124-127
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• 2016

Humidity calibration for a temperature-stable quartz oscillator (TSQO) was investigated to exclude the influences of relative humidity on the TSQO output in order to use the corresponding devices outdoors. The TSQO output is a voltage that is inversely proportional to the electric impedance of the quartz oscillator, which depends on the viscosity and density of the measured gas. The TSQO output was humidity calibrated using its humidity dependence, which was obtained by varying the relative humidity (RH) from 0 to 100 RH% while other conditions were kept constant. The humidity dependencies of the TSQO output were fit by a linear function. Subtracting the change in the TSQO output induced by the change in humidity, calculated with the function from the experimentally measured TSQO output for a range of 0-100RH%, eliminated the influence of humidity on the TSQO output. The humidity calibration succeeded in reducing the fluctuations of the TSQO output from 0.4-3% to 0.1-0.3% of the average values for a range of 0-100RH%, at constant temperatures. The necessary stability of the TSQO output for application in hydrogen sensors was below one-third of the change observed for a hydrogen leakage of 1 vol.% hydrogen concentration, corresponding to 0.33% of the change in each background. Therefore, the results in this study indicate that the present humidity calibration effectively suppresses the influence of humidity, for the TSQO output for use as an outdoor hydrogen sensor.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.803-811
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• 2014

This study was carried out to investigate the effect of relative humidity (70, 80, 90, and 95%) and to examine the interrelationship of temperature (15, 20, and $25^{\circ}C$) and relative humidity (60, 70, 80, and 90%) in the greenhouse on growth and occurrence of white rust in chrysanthemum 'Baekma'. The developmental stages of white rust were monitored from the initial occurrence to sporidium formation in teliospores. When the relative humidity of greenhouse was adjusted to 90% or more for 40 days, the occurrence rate of white rust, the number of infected leaves, and the number of symptoms per leaf were more than 97%, 10, and 55, respectively. However, in the treatment with 70% relative humidity, the occurrence rate of white rust dropped to 30% and only two spots of symptoms were observed with only 1 or 2 infected leaves per plant. The growth of cut flowers, such as fresh weight and leaf number, was the highest in 70% relative humidity. In the 90% relative humidity treatment, the first symptom of white spot appeared at 6 days after planting in chrysanthemum infected with white rust (stage 1), and then after one day, teliospores came out through the epidermal tissue of leaf (stage 2). The telium was formed with increasing teliospores after 1 to 2 days (stage 3), and then the promycelia developed from teliospores (stage 4). After a lapse of 4 to 5 days, sporidia formed on promycelia (stage 5). Regardless of relative humidity, white rust did not occur at all in treatments at $25^{\circ}C$. In treatments at $20^{\circ}C$, the number of sporidia was high regardless of relative humidity, but white rust did not occur in 60% and 70% relative humidity. As the relative humidity was higher, the number of sporidia and occurrence rate of white rust greatly increased, but the occurrence rate of white rust decreased to less than 14% in 60% and 70% relative humidity in treatment at $15^{\circ}C$.

• Composites Research
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• v.32 no.6
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• pp.382-387
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• 2019

A single frequency strain mode test, a stress relaxation mode test, and a creep test using RH-DMA were performed to investigate the effects of relative humidity and temperature on the viscous properties of PET film. The relative humidity was 10%, 30%, 50%, 70%, and 90%. The temperature was considered to be 30~95℃ for single frequency strain mode tests, 30℃ and 70℃ for stress relaxation mode test, and 5~95℃ for creep test. According to the results, higher relative humidity results in lower storage modulus and loss modulus, but the maximum value of the loss modulus is not significantly affected by changes in relative humidity and is almost constant. Relaxation modulus decreases rapidly at the beginning and becomes constant, and as the temperature increases, it is susceptible to changes in relative humidity. Strain recovery also increases rapidly at the beginning and is susceptible to changes in relative humidity as the temperature increases. In addition, as the temperature increases, the degree of increase in creep compliance increases, and as the temperature rises above the glass transfer temperature, the degree of increase becomes very large. The master curve determined by the time-temperature superposition provides the information to predict the long-term performance under operating conditions such as relative humidity and temperature.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.33 no.12
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• pp.81-90
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• 2017

This study was conducted to investigate the thermal environment status of nursery rooms in workplace daycare centers in Jeju and propose measures to improve their indoor physical thermal environment. For this purpose, measurements were performed in the winter indoor physical environment of 51 nursery rooms in 11 workplace daycare centers and a psychological evaluation survey on the thermal environment of nursery rooms was conducted for 70 nursery teachers. The investigation was carried out over 11 days in January 2017. The results are as follow. The average indoor temperature of the nursery rooms was $21.3^{\circ}C$($18.7-23.8^{\circ}C$) and the indoor temperatures of 47 nursery rooms (92.9%) were higher than the environmental hygiene management standard for domestic school facilities ($18-20^{\circ}C$). The average relative humidity was 33.9% (16.4-56.0%), and 37 nursery rooms (86.3%) showed a lower average relative humidity than the standard (40-70%). The average absolute humidity was $9.1g/m^3$ ($4.7-13.6g/m^3$), which was lower than the standard for preventing influenza ($10g/m^3$). When the indoor temperature and humidity of the nursery rooms were compared with international standards, it was found that 85% or more of the 51 nursery rooms maintained appropriate indoor temperatures, but 40-50% of the nursery rooms maintained a low humidity condition. Therefore, they need to pay attention to maintaining the appropriate humidity of the nursery room to keep the children healthy. The average indoor temperature of the nursery rooms showed a weak negative correlation with the average relative humidity. The indoor temperature had a significant effect on the relative humidity: a higher indoor temperature resulted in lower relative humidity. Regarding the fluctuations in the average indoor temperature of the nursery rooms during the day, in daycare centers that used floor heating, the indoor temperature gradually increased form the morning to the afternoon and tended to decrease during lunch time and the morning and afternoon snack times, due to ventilation. The daycare centers that used both floor heating and ceiling-type air conditioners showed a higher indoor temperature and greater fluctuations in temperature compared to the daycare centers that used floor heating only. In the survey results, the average value of the whole body thermal sensation was 3.0 (neutral): 32 respondents (62.7%) answered, "Neutral", Which was the largest number, followed by 21 respondents (30%) who answered, "Slightly hot" and 17 respondents (24.2%) who answered, "Slightly cold." Twenty-nine respondents answered, "Slightly dry," which was the largest number, followed by 28 respondents (54.9%) who answered, "Neutral" and 10 respondents (19.6%) who answered, "Dry." The total number of respondents who answered, "Slightly dry" or "Dry" was large at 39 (56.4%), which suggests the need for indoor environment management to prevent a low-humidity environment. To summarize the above results about the thermal environment of nursery rooms, as the indoor temperature increased, the relative humidity decreased. This suggests the effect of room temperature on the indoor relative humidity; however, frequent ventilations also greatly decrease the relative humidity. Therefore, the ventilation method and the usage of air conditioning systems need to be re-examined.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.773-777
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• 2002

In this study, we analyzed the LPG and LNG sensitivity measurement and voltage variation using catalytic type gas sensor characteristics in catalytic combustion type gas detecter sensors. gas detector shall operate as intended when exposed for 24 hours to air having a relative humidity of 0~85 percent at a temperature of $20[{\mu}m]$ and humidity of 45 percent at a temperature of $-10{\sim}40[^{\circ}C]$ the gas detecter sensors are to be subjected to operation for 210 days in an area that has been detemined to be equivalent to a typical residential atmosphere with an air velocity of 50 [cm/sec]. The source of energy for a gas detector sensors employing a supplementary basic circuit is energized from a separate source of supply direct applied voltage 2.1[V], 2.2[V], 2.3[V]. As a result, it was confirmed that the relative humidity and temperature by regression each analysis, compared to the LPG characteristic graph and methane characteristics graph by a relative humidity of 0 ~ 85 [%] at a temperature range of $-10{\sim}40[^{\circ}C]$ show a similar linear pattern on the whore.