• 한국환경보건학회지
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• 제40권2호
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• pp.98-104
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• 2014

Objectives: The purpose of this study was to determine airborne bioaerosols such as bacteria and fungi in the kitchens of restaurants, and to assess the effects of thermal factors on the levels of the bioaerosols. Methods: Air samples were taken from kitchens of nine restaurants. An Anderson type air sampler was used for sampling and measurements. Petri dishes filled with a microbiological culture medium (trypticase soy agar for bacteria and Sabouraud dextrose agar for fungi) were used as the sampling surface. Results: The levels of bacterial aerosol measured were $10-10^3CFU/m^3$ and fungal aerosol $10-10^2CFU/m^3$, respectively The mean values of air temperature and relative humidity in the kitchens were $24.6^{\circ}C$ and 46.4%, respectively. Overall, the levels of bacterial aerosol varied by the restaurant type, and fungal aerosol by the business period (p < 0.05). The main effect of air temperature and interaction effect of air temperature and relative humidity onto the bacterial level were significant (p < 0.05), whereas the effects were not significant onto the fungal level. Conclusions: The results indicate a wide variation in the levels of bioaerosols among different kitchens. The observed differences in bioaerosol levels in the kitchens reflect different periods of use. The interactions of air temperature and relative humidity onto the bacterial level suggest that constant attention should be paid to avoid peaks of contamination during the summer season.

• 자원ㆍ환경경제연구
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• 제25권2호
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• pp.277-297
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• 2016

본 연구는 기후변수들의 변동 특성이 한국 제조업의 총요소생산성에 미치는 영향을 분석하였다. 대표적인 기후변수인 기온, 강수량, 습도는 노동효율성에 부정적인 영향을 미칠 것으로 예상되므로 기온, 강수량, 습도의 변동특성이 한국 광역자치단체 제조업 총생산성에 미치는 영향을 분석하였다. 본 연구는 최근 기후변화로 기후 변동성이 높아지는 현상을 고려하기 위해 기후변수들의 평균값뿐만 아니라 최고값을 고려하여 분석하였다. 선형회귀분석 결과 선행연구 결과와 달리 기온과 습도가 제조업 생산성에 유의미한 영향을 미치지 않았다. 강수량의 평균적 증가는 부정적 영향을 미치는 것으로 분석되었다. 패널자료를 분석한 결과에서는 기온, 강수량 모두 제조업 총생산에 유의미한 영향을 주지 않는 것으로 나타났다. 반면 평균 습도의 상승은 제조업 총생산을 증가시키는 것으로 나타났다. 실내 작업이 많은 제조업의 경우 기후자체의 변화보다도 기업체들의 적응능력이 생산성 변화와 직접적인 관련이 있다. 한국 제조업의 경우 기온이나 습도의 변화가 급격하게 이루어지지 않고 있고, 냉난방 시스템 구축 등을 통해 기후변화에 잘 적응하고 있는 것으로 분석된다.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2370-2378
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• 2020

Building materials contribute significantly to the indoor radon and thoron levels. Therefore, parameters that influence the exhalation rates of radon and thoron from building material need to be analyzed closely. As a preliminary study, the effects of humidity on exhalation rates were measured using a system with an accumulation chamber and RAD7 detector for Korean brick, Korean soil, and Indonesian brick. Resulting doses to a person who resides in a room constructed from the building materials were assessed by UNSCEAR method for different air exchange rates. The measurements have revealed that Korean brick exhaled the highest radon and thoron while Indonesian brick exhaled the lowest thoron. Results showed that for a typical low dense material, radon and thoron exhalation rate will increase until reached its maximum at a certain value of humidity and will remain saturated above it. Analysis on concentration and effective dose showed that radon is strongly affected by air exchange rate (ACH). This is showed by about 66 times decrease of radon dose from 0.00 h^-1 to those of 0.50 h^-1 ACH and decrease by a factor of 2 from 0.50 h^-1 to those of 0.80 h^-1. In case of thoron, the ACH doesn't have significant effects on effective dose.

• 한국환경과학회지
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• 제25권5호
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• pp.683-694
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• 2016

Sensitivity analysis of the WRF model according to the impact of nudging (e.g., nudging techniques and application domains) was conducted during high nocturnal ozone episode to improve the prediction of the regional ozone concentration in the southeastern coastal area of the Korean peninsula. The analysis was performed by six simulation experiments: (1) without nudging (e.g., CNTL case), (2) with observation nudging (ONE case) to all domains (domain 1~4), (3) with grid nudging (GNE case) to all domains, (4)~(6) with grid nudging to domain 1, domain 1~2 and domain 1~3, respectively (GNE-1, GNE-2, GNE-3 case). The results for nudging techniques showed that the GNE case was in very good agreement with those observed during all analysis periods (e.g., daytime, nighttime, and total), as compared to the ONE case. In particular, the large effect of grid nudging on the near-surface meteorological factors (temperature, relative humidity, and wind fields) was predicted at the coastline and nearby sea during daytime. The results for application domains showed that the effects of nudging were distinguished between the meteorological factors and between the time periods. When applied grid nudging until subdomain, the improvement effects of temperature and relative humidity had differential tendencies. Temperature was increased for all time, but relative humidity was increased in daytime and was decreased in nighttime. Thus, GNE case showed better result than other cases.

• 한국의류산업학회지
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• 제25권1호
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• pp.119-126
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• 2023

This study aimed to determine the effects of relative humidity and fiber properties on the moisture permeability of multilayer systems by measuring water vapor transmission in the overlapping condition of various fabrics. The results confirmed that the property of the fabric in contact with the humid environment affects the moisture permeability. If the layer facing the humid environment is hydrophobic and the layer facing the dry environment is superhydrophobic, water vapor transmission increases by up to 17.8% compared to the opposite conditions. Comparing the correction values of the water vapor transmission reflecting the thickness of the specimen under the multilayer condition showed that permeability was higher when the hydrophilic or hydrophobic layer was facing the humid environment. The opposite was true from the "push-pull" effect of absorption mechanism. In the case of moisture permeability, the more hydrophilic the surface facing the humid environment, the more permeable that water vapor diffuses and passes through. It was concluded that the "pull-push" effect, in which water vapor diffuses widely through the hydrophilic facing a humid environment and then passes through the hydrophobic layer, contributes to the improvement of permeability. Permeability differed according to the multilayer overlapping condition. When the relative humidity was high, the "pull-push" effect was insignificant. This is caused by water droplets absorption after the partial migration of water due to condensation. These results suggest that the overlapping conditions and properties of fabrics should vary depending on heavy sweating or not.

• 한국가금학회지
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• 제21권2호
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• pp.119-131
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• 1994

The physiological functions of drinking water in chicken were reviewed. The effects of ambient temperature, humidity, wind velocity, egg productivity, feed form, nutrients density, and breed types on the water consumption of chicken were summarized and discussed. Some guidelines for management of drinking water in commercial poultry farms were also suggested.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2005년도 추계 학술발표논문집
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• pp.197-201
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.79-79
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• 2005

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2004년도 제19회 발표논문집
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• pp.47-52
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• 2004

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.125-129
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• 1997

The effects of the moisture and thermal annealing on CLBO crystal have been investigated. CLBO has hydrated at high humidity condition, resulting in 5B$_2$O$_3$$.$Cs$_2$O$.$8H$_2$O. The surface hydration seems to induce the cracking and the refractive index change in CLBO. The thermal annealing is effective to restore the changed index.