• Korean Journal of Pharmacognosy
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• v.38 no.2 s.149
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• pp.157-163
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• 2007

Trillium tschonoskii Maxim. is a kind of 64 endangered plant species designated by the Ministry of Environment in Korea. It is very a rare native plant throughout the country. Therefore, this study was conducted to investigate the native T. tschonoskii in Ulleung Island for their distribution and ecological characteristics. They were mostly distributed valley, mid-slope of the mountain from 186 to 458 m altitude. They had a little low light conditions as they faced west, north west, south west, south-south west, north-north east and east-east north. They were provided with slightly humid condition. Aerial humidities of these quadrates were variable as 21.5-71%. They were located on the variable slopes of 5 to 43 degrees. Soil humidity was slightly dry. Native sites were semi-shaded because tree layer such as Tilia insularis, Zelkova serrata, okamotoanum etc.and sub-tall tree layer such as Ligustrum foliosum, Comellia japonica, Tilia insularis, Callicarpa japonica and so on were grown near by. Woody plants such as A. Okamotoanum, Sorbus commixta, Fagus japonica var. multinervis etc. were frequently observed. These environmental conditions were suitable that T. tschonoskii grows up naturally because of high Percentage as 52.78% of blooming individuals in this study. These native sites were classified with three communities, T. tschonoskii-Majanthemum dilatatum community, T. tschonoskii-Anthriscus sylvestris community and T. tschonoskii-Hepatica maxima community in accordance with altitude and aerial humidity. The best way ffr the preservation of T. tschonoskii habitats and maintainance of its recent population is maintained in recent environmental condition and ecological condition without any management by human-being.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.420-425
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• 1986

This study was conducted to investigate the influence of air temperature and relative humidity on excessive drying rate of burley tobacco. In experiment I, 4 temperatures and I humidity by day and air curing by night were treated from initial curing stage. In experiment II, 15 combinations of 3 temperatures and 5 humidities were applied from the yellow stage of cure. Yellowish cured leaves resulted from overdrying at high temperature and especially, at low humidity. How- ever, these were not produced at 75-80% RH and under 35$^{\circ}C$ by day with air curing b y night. The proper range of temperature and humidity for desirable color of cured leaf were the combinations of 30$^{\circ}C$, 75-80% RH or 35$^{\circ}C$, 80-85% RH. As excessive drying leaves increased, physical properties of cured leaves were poorer and chemical contents were less decomposed.

• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.181-191
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• 2009

As an effort to prevent serious accidents involving oxygen deficiency and suffocation in confined spaces and to identify the causes of such accidents, the present study investigated relevant accidents and systems in Korea and other countries. This study also conducted a number of experiments at lethal concentration levels of oxygen deficiency using SD rats and observed the changes of experimental animals with humidity, organic gas (toluene), hydrogen sulfide, carbon monoxide and so on at the oxygen deficient environment. The results of the study are as follows. 1. The results from the experiment conducted using SD rats at lethal concentration levels of oxygen showed that there were no casualties at the 7% oxygen concentration level, but the mortality increase to 20% at 6% oxygen, it was jumped to 90% at 5% oxygen, and it was also dramatically reached 100% at 4% oxygen concentration. Therefore, 5.5% was calculated as the $LC_{50}$ (rat, 4hr) from these dose-response experiments with oxygen deficiency. 2. When we changed the level of toluene, $H_2S$, CO, humidity, and so on, in an oxygen deficient environment, it was observed that the small concentrations of $H_2S$ and CO make the highest effect on animals. In case of 350 ppm $H_2S$, it resulted in 30% mortality, and the 100% mortality was shown in 1,200 ppm CO concentration. The mortality increased as an oxygen deficient condition. However in the case of toluene up to 1,000 ppm, it were not affected with oxygen deficiency, and it did not indicate any significant differences in mortality as 20%, 90% humidities.

• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.229-244
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• 1998

This study was performed to determine proper fan and heater management schemes for natural air drying of rough rice in round steel bin with stirring device under Korean weather conditions. A computer simulation model was developed to predict moisture content changes, energy requirements, and drymatter losses during drying of rough rice by natural air. Drying test was conducted to validate the simulation model using round steel bin of holding capacity of 300ton at Rice Processing Complex in Jincheon. The bin was filled with rough rice every day and mixing by stirring device. Moisture contents, ambient air temperatures, relative humidities, static pressures in plenum chamber in the bin, airflow rates, and electrical and fuel energy were measured. Relative errors of moisture content changes predicted by the simulation model were below 5ft, and relative errors of final moisture content, final grain weight, required energy ranged from 0.9% to 6%. These not levels indicated that the simulation model can satisfactorily predict the performance factors of natural air drying system such as drying rates and energr consumptions comparing error level of 10% to 15% in other drying simulation models generally used in dryer desists. Twelve different fan and heater management schemes were evaluated using the computer simulation model based on three hourly weather data from Suweon for the period of 1952-1994. The best management schemes were selected comparing the drymatter losses, required drying times, required energy consumptions. Operating fan without heating only when ambient relative humidity was below 85% or 90% appeared to be the most effective method of In operation in favorable drying weather. Under adverse drying climates or to reduce required drying time, operating fan continuously, and heating air with $1.5^{\circ}C$ temperature rise only when ambient relative humidity was over 85% appeared to be the most suitable method.

• Journal of Biosystems Engineering
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• v.27 no.3
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• pp.219-226
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• 2002

Desorption equilibrium moisture contents of oak mushroom were measured by the static method using salt solutions at flour temperature levels of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 6$\^{C}$ and five relative humidity levels in the range from 11.0% to 90.8%. EMC data were fitted to the modified Henderson, Chung-Pfost, modified Halsey and modified Oswin models using nonlinear regression analysis. Drying tests far oak mushroom were conducted in an experimental dryer equipped with air conditioning unit. The drying test were performed in triplicate at flour air temperatures of 35$\^{C}$, 45$\^{C}$, 55$\^{C}$ and 65$\^{C}$ and three relative humidities of 30%, 50% and 70% respectively. Measured moisture ratio data were fitted to the selected four drying models(Lewis, Page, simplified diffusion and Thompson models) using stepwise multiple regression analysis. The results of comparing root mean square errors for EMC models showed that modified Halsey was the best model, and modified Oswin models could be available far oak mushroom. The results of comparing coefficients of determination and root mean square errors of moisture ratio for four drying models showed that Page model were found to fit adequately to all drying test data with a coefficient of determination of 0.9990 and root mean square error of moisture ratio of 0.00739.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.99-104
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• 1985

This research was carried out study the effect of several relative humidities on the cracking of kernels of chestnuts. The moisture contents of total kernel increased at the higher humidity over 88% relative humidity. but the moisture contents of inner layer was decreased at low relative humidity below 76 %. The starch contents of kernel decreased, but free stgars increased during the total period of storage. The tannin contents increased during total of storage, and the tannin contents of out layer was higher than inner layer because of tannin transfer from astringent shell. As we considered the sprouting ratio, the rotting ratio and the cracking ratio, the optimal relative humidity of chestnut storage was proved 88% relative humidity.

• Food Science and Preservation
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• v.5 no.1
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• pp.7-12
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• 1998

Chestnuts(Castanea cretana, Eunki) were used for quality evaluations from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 8 months. Quality criteria included spouting, rotting, weight loss, and the changes in moisture, total sugar, reducing sugar, and total vitamin C of the stored sample. Sprouts(roots) were developed in about 2 months in all stored samples which had been mixed with sawdust(50% moisture) and stored under the conditions of 2∼25$^{\circ}C$ and 62∼95% RH. The sprout development was more significant in the storage temperature of Pit(9${\pm}$6$^{\circ}C$, 80${\pm}$5% RH, PT)and room(16${\pm}$7$^{\circ}C$, 85${\pm}$10% RH, RT) than low(3${\pm}$1%, 80${\pm}$5% RH, LT)and ambient(14${\pm}$11$^{\circ}C$, 67${\pm}$5% RH, AT). The rates of rotting and weight loss were appreciable in the order of PT, AT, RT and LT, and those of LT were 1∼2%. The use of wet sawdusts resulted in the increase of moisture contents in stored samples, thereby causing the rotting phenomena. Some chemical components of stored samples were found liable to the changes according to storage conditions, that is; total sugars showed a decreasing tendency along with a temporary increase during storage, and both reducing sugar and vitamin C were similarly accumulated in the samples stored at low temperature conditions. The results indicated that long-term storage of chestnuts will be possible in either cases of the application of low temperature following sprout-inhibition treatment or the use of lower temperature than 0$^{\circ}C$ to suppress its sprouting during storage.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.1-6
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• 1980

The sorption characteristics of red pepper powder were analyzed in respect to its storing humidities and the types of powder product. The sorption rate of the powder was affected by the humidity values under which it was stored. At low relative humidity values below 70% RH the sorption equilibrium was easily attained, but at the higher humidity over 75% RH the equilibrium state was not reached even after a long period of storage. From the estimation of the sorption rate at arbitrary humidity an empirical equation was obtained; In ${\frac{dw}{dt}}=n\;ln(t)+ln\;c$, where w is moisture content(%) absorbed, t is time (hour) and n and c are empirical constants which were determined from empirical data. Particle sizes and drying methods of red pepper showed little effect on the sorption behavior.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.717-723
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• 2008

The purpose of this study is to measure and analyze the indoor thermal conditions of a 8,500GT class chemical carrier which was launched on July 2007. The measurement was operated from 4th June to 4th June 2007, just before handing over to Owner. Followings are the results of this study. (1)The temperature variations of supply air were related to the outdoor temperature variations, but the humidity was stable at $65{\sim}80%$. (2)The temperature variations at the representative position of bridge, restaurant, crew's cabin showed gentle slopes. but that of conference room was very steepy. The humidities of bridge and restaurant were unstable because of outdoor-contact and cooking, respectively. (4)The temperature and humidity of ECR(Engine Control Room) which was designed to supply heating and cooling by PAC(Package Air Conditioner) were directly affected by the operating conditions of PAC. (5)The measured supply air volume from dampers of bridge, crew's cabin and conference room were satisfied with the design supply air volume. (5)For the improvement of the indoor thermal conditions, the temperature of crew's cabin and restaurant and the humidity of conference room, and the temperature and humidity of bridge should be controlled, respectively.

• Ecology and Resilient Infrastructure
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• v.7 no.1
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• pp.43-52
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• 2020

For investigating restriction in the use of computer modeling results without adjusting them with measured data, this study analyzed and compared microclimatic aspects and human thermal sensation between in situ measurement and computer modeling using ENVI-met in and around a small urban park of downtown Changwon in May, 2012. In the results, ENVI-met underestimated air temperatures and wind speeds than the measured ones and overestimated relative humidities. In the radiation analysis, ENVI-met overestimated solar radiation from the sky hemisphere and terrestrial radiation from the ground hemisphere and underestimated terrestrial radiation from the sky hemisphere. Also, the differences of mean radiant temperatures with the measured ones reached up to 19.6℃ which could create an 1.2 PMV difference. ENVI-met overestimated up to 2.3 PMV and 4℃ UTCI at 12:00. The difference was shown clearly in PMV than in UTCI. Therefore, when computer modeling is used in urban microclimate and human thermal sensation (comfort) studies the modeling results should be compared with measured data and adjusted adequately to adopt the results to urban and landscape planning and design.