• 터널과지하공간
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• 제6권4호
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• pp.335-341
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• 1996

This fundamental study analyzes the relationship between rock thermal properties and psychrometric properties in underground space and has a ultimate goal to develope technologies for predicting major environmental variables. The study is divided into 2 subjects (1) developement of a basic model for predicting temperature and humidity, (2) analysis of the validity of the model through application to a local underground storage space for military supplies. The basic model is built for the network of tunnel-shaped underground spaces. The model takes into account rock thermal properties and changes in moisture content in the air due to condensation/evaporation on the rock surface. Using lumped-parameter analytical method, heat flux from or to the surrounding rock is calculated and then the psychrometric properties(air quantity, pressure, temperature, humidity) are estimated through network simulation. The model can be utilized regardless of the tunnel type. The study site is a local storage space built in rock, mainly granite gneiss and quartz-porphyry. It is a U-shaped tunnel, 593.5m long and 6x6.5m wide. Relative humidity inside has to be strictly controlled under 55% to avoid erosion of a certain types of supplies stored in 6 chambers with the capacity of 300~1.000 ton. The thermal conductivity varies between 2.734 and 2.779W/m$^{\circ}C$ and the thermal diffusivity is in the range of 1.119 and $1.152{\times}10^{-6}\;m^2/s$ the specific heat between 910 and $920\;J/kg^{\circ}C$. Relative errors of the predicted values of dry/wet temperature and relative humidity are 0.8~3.0%, 0~7.5% and 0~7.0%, respectively. Apparent errors associated with the rock surface temperature seems to be partly due to the intrinsic limitations in the infrared thermometer used in this study.

• Journal of Ecology and Environment
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• 제36권1호
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• pp.65-71
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• 2013

The concentration of airborne pollen is related to meteorological parameters. The main purpose of this study was to determine the correlation between airborne pollen and meteorological parameters in Ulsan based on sampling from 2010 to 2011. The primary factors of interest were differences in the pollen scattering start date, end date, and peak date, and the fluctuations in pollen concentration. The meteorological parameters that affected the start and peak dates of the pollen season were as follows. For Pinus and Alnus, the dates were correlated with sunshine and an increase in temperature, whereas for Quercus, the dates were correlated with increasing temperature. During the pollen season, Alnus peaked when the temperature was highest and Pinus peaked when the relative humidity was lowest. The concentration of airborne pollen was correlated with meteorological parameters during the sampling period as follows: Pinus, Alnus, and Humulus pollen concentrations were positively correlated with increasing temperature and negatively correlated with rainfall and relative humidity; Humulus pollen concentration was positively correlated with sunshine; and Quercus and Humulus pollen concentrations were positively correlated with wind speed.

• 한국환경보건학회지
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• 제42권2호
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• pp.133-140
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• 2016

Objectives: A pilot study was undertaken to assess the bioaerosol levels in restaurants and determine the effects of variations in temperature, relative humidity, and air movement on these levels. It focused on the differences between kitchens and dining areas, as well as between summer and winter. Methods: A field survey was performed in six restaurants. An Anderson type air sampler was used for sampling bioaerosols, such as total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The average levels of TSB were $1{\times}10^2CFU/m^3$ and of TSF they were $1{\times}10^0{\sim}10^1CFU/m^3$. The kitchens had higher bioaerosol levels compared to dining areas, and summer showed much higher levels than winter. The concentration of OP in summer was more than six-fold that of winter. S. aureus was detected both in kitchens and dining areas, even in winter. The main effect of air movement on TSB levels was significant (p<0.05), as was air temperature, relative humidity and air movement on TSF levels (p<0.05). Conclusion: There was a wide variation in bioaerosol levels among different restaurants. The results indicate that cooking foods may be a key factor affecting bioaerosol levels. The effects of air temperature and relative humidity reveal that bioaerosol levels may vary according to the season. The observation of pathogenic bacteria suggests that the hygiene management of establishments should be improved. Future research is needed to characterize the relation between bioaerosol levels and the occupant density of the dining area.

• 원예과학기술지
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• 제32권6호
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• pp.803-811
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• 2014

본 연구는 스탠다드 국화 '백마'의 흰녹병 발생과 생육에 미치는 시설 내의 상대습도(70, 80, 90, 95%)의 영향을 조사한 후, 온도(15, 20, $25^{\circ}C$)와 상대습도(60, 70, 80, 90%)의 상호관계를 알아보고자 실시되었다. 또한 흰녹병의 발생 초기부터 동포자퇴에서 소생자가 형성될 때까지 병 발생 단계를 관찰하였다. 국화 '백마'를 시설 재배 시 상대습도를 90% 이상 조건에서 40일간 처리되었을 때, 흰녹병 발생률이 97%, 주당 발병엽수가 10개, 발병엽당 병징수가 55개 이상으로 나타났다. 그러나, 상대습도를 70% 이하로 유지하면 흰녹병 발생률을 30% 낮출 수 있고, 한 주당 1-2개의 감염된 잎에 2개의 병징만 나타나 병해를 크게 줄일 수 있었다. 생체중과 엽수와 같은 절화의 품질은 다른 처리보다 상대습도 70% 처리에서 가장 우수하였다. 상대습도 90% 처리구에서 흰녹병에 감염된 국화를 정식한 후 6일 후에 첫 병징인 흰색 반점이 나타났고 (1단계), 1일 경과 후에 동포자가 잎의 표피 조직을 뚫고 나왔으며(2단계), 1-2일 후에 동포자의 수가 증가하면서 동포자퇴가 크게 형성되었다(3단계). 동포자에서 1-2일 후에 전균사체가 발달하였고(4단계), 4-5일 경과된 후 전균사체에서 소생자가 형성되었다(5단계). 시설 내 온도를 $25^{\circ}C$로 처리했을 때, 상대습도에 관계없이 흰녹병이 전혀 발생하지 않았다. 시설 내 온도가 $20^{\circ}C$에서는 상대습도에 관계없이 소생자수가 많았으나, 60%와 70%에서는 흰녹병이 발생하지 않았다. 시설 내 온도가 $15^{\circ}C$에서는 상대습도가 높을수록 소생자수가 많았고, 흰녹병 발생률도 높아졌으나, 상대습도가 낮은 60-70% 처리에서는 흰녹병 발생률이 14% 이하로 낮았다.

• Asian Journal of Atmospheric Environment
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• 제11권3호
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• pp.184-193
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• 2017

People spend the majority of their time in indoor environments. Maintaining adequate indoor temperature and humidity is necessary to support health and improve quality of life. However, people with low incomes can be vulnerable because they may not be able to use effective cooling and heating systems in their homes. In this study, the indoor temperature and humidity in low-income residences over a year in Seoul, Korea was characterized. Indoor temperature and humidity were measured in three types of homes (12 rooftop residences, 16 basement residences, and 18 public rental apartments) occupied by low-income residents. Both differed significantly among the three types of residence, particularly during the summer and winter seasons. A regression model between indoor and outdoor temperature detected a heating threshold at $3.9^{\circ}C$ for rooftop residences, $9.9^{\circ}C$ for basement residences, and $17.1^{\circ}C$ for public rental apartments. During tropical nights and cold-wave advisory days, rooftop residences showed the most extreme indoor temperatures. This study demonstrates that people living in rooftop residences could be at risk from extreme hot and cold conditions.

• 한국농공학회지
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• 제41권6호
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• pp.44-53
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• 1999

The statistical characteristics of the factors related to the daily rainfall prediction model are analyzed . Records of daily precipitation, mean air temperature, relative humidity , dew-point temperature and air pressure from 1973∼1998 at 8 meteorological sttions in south-western part of Korea were used. 1. Serial correlatino of daily precipitaiton was significant with the lag less than 1 day. But , that of other variables were large enough until 10 day lag. 2. Crosscorrelation of air temperature, relative humidity , dew-point temperature showed similar distribution wiht the basin contrours and the others were different. 3. There were significant correlation between the meteorological variables and precipitation preceded more than 2 days. 4. Daily preciption of each station were treated as a truncated continuous random variable and the annual periodic components, mean and standard deviation were estimated for each day. 5. All of the results could be considered to select the input variables of regression model or neural network model for the prediction of daily precipitation and to construct the stochastic model of daily precipitation.

• 한국산업보건학회지
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• 제30권1호
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• pp.18-27
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• 2020

Objectives: For testing asbestos stabilizer products which are used for the maintenance and management of asbestos-containing materials, durability assessment should accompany the evaluation of basic properties and performance. Therefore, in this study we designed a testing method and constructed a database of durability performance, thereby providing basic data for reliability studies of asbestos stabilizer. Methods: Since the ceiling materials targeted in this study are interior materials, test conditions of 95% relative humidity and 60℃ temperature were designed in consideration of the effect of high relative humidity in summer and seasonal indoor temperatures. Plate-shaped specimens treated with asbestos stabilizers were maintained in a thermo-hygrostat for 5, 10, and 20 days, and then the asbestos scattering prevention rate was measured by air erosion testing. Results: The scattering concentration tended to increase with time under the single humidity condition, and exceeded the indoor air quality standard of 0.01 f/cc, during the 20 days of maintenance. On the other hand, there was little change according to the temperature condition. In the case of a complex condition with temperature and humidity, the results were similar to the humidity test, but the scattering concentration increased more sharply at 20 days. Conclusions: The main deterioration factor that affects the durability of asbestos stabilizer is humidity, and the deterioration is caused by a mechanism in which the stabilizer coated on the surface is re-dissolved by moisture and evaporates or the coating layer is peeled off, which is accelerated by high temperatures.

• 한국의류학회지
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• 제25권8호
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• pp.1475-1483
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• 2001

The purpose of this study was to determine the physiological responses and subjective sensation according to fiber content of socks. Six female students participated in the wear trial test which was conducted in controled environmental chamber with 26${\pm}$1$^{\circ}C$ and 60${\times}$3%. R.H.SAS program was used for statistical analysis. The results of this study were as follows. Mean skin temperature was significantly different among three different socks. AWNP socks had the highest mean skin temperature and instep temperature. Also relative humidity in the microclimate of socks as well as heart rate were influenced by fiber content of socks, However, test of subjective sensation such as thermal, humid, comfort sensation showed that there was no significant difference among three different socks thermal sensation during the exercise and recovery period.

• 복식
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• 제63권5호
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• pp.102-114
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• 2013

This study performed the evaluation of skin temperature, heart rate, humidity and temperature inside clothing, and subjective sensation to estimate the physiological responses of the human body and its feeling of comfort for developing value-added dox fabric. Experiments were performed on five healthy adult women whose average age was 21, at climate chamber in which temperature, relative humidity and air current were set up below $28{\pm}5^{\circ}C$, $50{\pm}10%$, 0.2m/s, respectively. Two kinds of clothes were used for the experiments: 100% cotton and dox clothes. The clothes were identical in size and form, and the attire consisted of long-sleeved shirts, long trousers, and socks. The experiment was performed for 30 minutes using ergometer. The results are as follows. 1) It showed low skin temperature of forearm, breast, back, forehead and lower leg in exercise, but high skin temperature of them in recovery. However skin temperature of thigh and foot increased from rest to recovery. 2) It showed significant difference (p<0.001, p<0.01) in average skin temperature between cotton and dox clothes. Cotton clothes had a higher average skin temperature compared to dox. Not only was there a significant difference in temperature inside clothing (p<0.001), this was also the case with humidity inside the clothing (p<0.001).

• 한국환경과학회지
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• 제7권1호
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• pp.36-40
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• 1998

This study was carried out to investigate the collection Efficiency of mass in collector step at the different of physical gas characterization. This work has focused on the dependence of the collection efficiency of mass in the collector zone of a two-stage set up field with gas temperature T and the dew point tmeperature. To identify the dependence of the mass collection efficiency on the Bounded plate of the collector zone MP.k by the spectre electric resistance of dust $p_e$. and the relative humidify ${\varphi}$, 20 at- tempts have been made with three different gas temperature ($50{\circ}C, 80{\circ}C, 110{\circ}C$) at different dew point. At the specific electric resistance of dust $p_e$=$10^6{\Omega}m$ which relative humidity corresponds to $\phi$ > 15%, a easy rise of the sounded plate secluded dust mass share was measured atwain. As the result of the higher cohesion imprisonment power due to the adsorbtion of particle, the rinse of the relative humidity developed on the particle surface. Therefore, the collection efficiency of mass was not predominant the high temperature T in the collector zone, neither was the pecific ellectric resistance of dust dependent.