• 제목/요약/키워드: Inside humidity

검색결과 379건 처리시간 0.022초

서울 일부 지하철 객차와 승강장에서 측정한 $PM_{10}$$PM_{2.5}$농도의 특성 (Characterization of $PM_{10}$ and $PM_{2.5}$ Levels inside Train and in Platform of Subway)

  • 박동욱;윤경섭;박수택;하권철
    • 한국환경보건학회지
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    • 제31권1호
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    • pp.39-46
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    • 2005
  • This study was performed to investigate the concentration of $PM_{10}$ and $PM_{2.5}$ in inside train and platform of subway 1, 2, 4 and 5 in Seoul, KOREA. $PM_{10}$, $PM_{2.5}$, temperature, humidity and carbon dioxide were monitored using Portable Aerosol Spectrometer at afternoon (between 13:00 and 16:00). The concentrations of $PM_{10}$ and $PM_{2.5}$ in inside train were monitored to be higher than those measured in platform. In addition, $PM_{10}$ concentration in both platform and inside train were found to be greatly higher than range of from 35 ${\mu}g/m^3$ to 81${\mu}g/m^3$ in ambient air reported by Ministry of Environment. This study found that there were many inside train in subway 1, 2, 4 line where exceeded 150 ${\mu}g/m^3$ of Korean PM10 standard. The average percentage that exceeded PM10 standard was 83.3% in line 1, 37.9% in line 2 and 63.1% in line 4, respectively. In particular, most of inside train in subway line 1 were over PM10 limit. PM2.5 concentration ranged from 77.7 ${\mu}g/m^3$ to 158.2 ${\mu}g/m^3$, which were found to be greatly higher than ambient air PM2.5 standard promulgated by United States Environmental Protection Agency (US-EPA) (24 hours arithmatic mean : 65 ${\mu}g/m^3$, year average : 15 ${\mu}g/m^3$). The percentage of $PM_{2.5}$ in $PM_{10}$ was 86.2% in platform, 81.7% in inside train, 80.2% in underground and 90.2% in ground. These results indicated that fine particles ($PM_{2.5}$) accounted for most of $PM_{10}$.

지하공기-물 직접접촉식 열교환기를 구비한 히트펌프의 성능 (Performance of Underground Air-to-Water Heat Pump with Direct Contact Heat Exchanger)

  • 김영화;강연구;성문석;유영선;김종구;장재경
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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    • pp.172.1-172.1
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    • 2010
  • In Jeju, underground air is used for heating greenhouse and fertilizing natural $CO_2$ gas by suppling directly into greenhouse. But greenhouse heating method by direct supply of underground air has several problems as like low temperature below $20^{\circ}C$ or high relative humidity over 90%. The underground air is inadequate in heating of crops such as mangos, oranges with the growing temperature over $20^{\circ}C$. Also if the relative humidity of greenhouse is kept with over 90%, diseases can strike almost of the crops. And also the ventilation loss becomes larger because the air pressure of inside greenhouse by direct supply of underground air is higher. In this study the heat pump system using underground air as heat source was developed and heating performance of the system was analyzed. Heating COP of the system was 2.5~5.0 and rejecting heat into greenhouse and extracting heat from underground air in this heat pump system were 46.5~31.4 kW, 34.9~20.9 kW respectively.

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지뢰 탐지용 방호복 구성과 방호성능 및 착용감 평가 (A Study on The Development and Evaluation of Mine Detective Gear)

  • 손부현;최혜선
    • 한국의류학회지
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    • 제25권4호
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    • pp.707-718
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    • 2001
  • The purpose of this study is to evaluate a newly developed protective suit with the fragments of grenade. The protection efficiency should be strengthened upon the degree of wound. The fragment weight of the used grenade was measured and the kinetic energy of the maximum speed of the fragments in the field test was 137.7J and this could be the protective efficiency test by the multitude fragments in less than 0.031g of the M16A1. The panel inserted to the new demining suit has protection rate of 100% within the distance of 1m and sample II has protection rate of 100% only beyond the distance of 5m. The test showed that the protection rate on the protective suit of the existing garment was comparatively high, however, the protection rate of the sleeve part was very low. The new demining suit through the research demand some complementary measures to lower the temperatures in ear, average skin temperatures, and the temperatures-humidity inside the clothing for summer climate condition, It showed that 30 minutes of rest on the clothing was difficult to go back to the original condition. But in winter climate condition, there was no problem in the temperature, humidity, and comfort to go back to the original condition during the rest and was better in warmth.

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외기에 면한 초고층 아파트 천정 내부결로 예측 (Forecast on Internal Condensation at Ceiling of Super-high Apartment Building Faced with Open Air)

  • 안재봉;송영웅;최윤기
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2003년도 학술대회지
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    • pp.626-629
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    • 2003
  • 본 연구는 외기에 면한 초고층 아파트 최상층부의 발코니 천장내부에 있는 H-Beam(내화피복+단열재로 구성)과 Parepet 부위 내부결로 발생가능성에 대한 예측을 해 봄으로써 해당공간 거주자의 쾌적한 환경 만족 및 불안을 해소 하는데 그 목적이 있다. 외주부를 성하고 있는 Curtain wall, Stone panel 또는 슬래브 바닥하부 등의 열적 취약공간에 대해 2차원 정상상태(온도평형) 열전도해석 Program을 이용, 온도예측과 온도분포해적을 통해 해당부위의 습기압분포에 따른 내부결로 예측을 실시하였다.

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비강 내 공기유동과 열 및 물질전달에 관한 연구 (Research on the nasal airflow and heat and mass transfer)

  • 김성균;휜광림;박준형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1479-1483
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    • 2008
  • The three main physiological functions of nose are air-conditioning, filtering and smelling. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time, airflow inside normal nasal cavity is investigated numerically by the FVM general purpose code. The comparisons with PIV measurement are appreciated. Heat and humidity transfer is dealt numerically. Dense CT data and careful treatment of model surface under the ENT doctor’s advice provide more sophisticated cavity models for both PIV experiment and numerical grid system. Average and RMS velocity distributions have been obtained for inspirational and expirational nasal. Temperature distribution, heat and humidity transfer through the mucosa are obtained.

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OpenFOAM을 이용한 대규모 환경재현 시스템 내에서의 환경변수 제어 시뮬레이션 (NUMERICAL SIMULATION ON CONTROL OF ENVIRONMENTAL VARIABLES FOR ENVIRONMENT REPRODUCTION SYSTEM USING OPENFOAM)

  • 정세민;;박종천
    • 한국전산유체공학회지
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    • 제18권1호
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    • pp.43-48
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    • 2013
  • The feasibility of a unique greenhouse, named as Gradient Biome, is now being examined extensively in the University of Tokyo. It is a large chamber (length:200m, width:50m, height:40m) in which the weather, such as temperature and humidity, of the tropical zone through to that of the frigid zone on the earth is reproduced with continuous gradient. In the Gradient Biome, ecosystems (mainly plants) corresponding to each weather are introduced and the possible responses of this ecosystems to the expected global warming are to be observed. Since one of the expected responses is the shift of the ecosystem(s) toward the region of suitable environment, there should be no artificial obstacles, which can prevent the shift, inside the Biome. This requirement is not so easy to be satisfied since the environment tends to be homogeneous. This paper presents the results of the numerical studies conducted to find the ways of how the temperature and humidity in the Gradient Biome could be reproduced. One of the contributed solvers of OpenFOAM, which is an open source physics simulation code, was modified and used for the numerical simulations.

CFD를 활용한 연료전지 모듈 보호가스 유동 연구 (CFD-based Flow Simulation Study of Fuel Cell Protective Gas)

  • 권기욱;임종구;박종철;신현길
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 추계학술대회 초록집
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    • pp.86.1-86.1
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    • 2011
  • To improve the safety, the fuel cell operate inside a pressurized enclosure which contains inert gas so called protective gas. The protective gas not only prevents the mixture of hydrogen and oxygen, but also removes the water in the vessel with the condenser. This study presents the details of the flow optimization in order to reduce the humidity in the fuel cell housing. The protective gas flow in the fuel cell container is studied by Computational Fluid Dynamics(CFD) simulations. This study focuses on optimizing the geometry of an protective gas circulation system in fuel cell module to reduce the humidity in the vessel. CFD analysis was carried out for an existing model to understand the flow behavior through the fuel cell system. Based on existing model CFD results, geometrical changes like inlet placement, optimization of outlet size, modification of fuel cell module system are carried out, to improve the flow characteristics. The CFD analysis of the optimized model is again carried out and the results show good improvement in protective gas flow behavior.

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PCM 마이크로캡슐을 이용한 열조절 섬유소재 개발 -열조절 섬유소재의 착용효과- (Development of Thermoregulating Textile Materials with Microencapsulated Phase Change Materials(PCM) -Wearing comfort of the developed thermoregulating textile materials-)

  • 신윤숙;정영옥;전향란;손경희;김성희
    • 한국의류학회지
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    • 제28권6호
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    • pp.767-775
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    • 2004
  • In order to evaluate physiological responses and comfort sensation of the developed thermoregulating textile material, polyester knit fabric was treated with phase change material (PCM) microcapsules by printing. Ten male subjects wearing an experimental best with and without PCMs were seated for 20 minutes, then exercised for 20 minutes, and then seated for 30 minutes in the chamber which was controlled under the temperatures of 20$\pm$1$^{\circ}C$, 50$\pm$5%R.H. The subject's skin temperature, microclimate inside garment and comfort sensation of two experimental bests were compared one another. As a result, the rectal temperature, skin temperature and mean skin temperature were similar in the two groups, and the subjects were not able to perceive the differences in comfort of the two experimental bests. However, the effect of PCM microcapsule could be seen from microclimate temperature and humidity. The microclimate temperature of the PCM garment at chest was significantly higher during exercise. The microclimate humidity of the PCM garment at chest was significantly lower during exercise and rest.

유물의 보존환경에 대한 생물학적 조사 연구 (Biological Investigation on Conservational Environment of Collections)

  • 이명혜;이규식;한성희;안희균
    • 보존과학연구
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    • 통권13호
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    • pp.96-112
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    • 1992
  • We made biological investigation on the conservational environment of collections in the Ho Am museum. Annual average temperature and relative humidity outside the museum were $11. 0∼11.7^{\circ}C$ and 64.8∼74.4% respectivey. On the other hand, average annual temperature and relative humidity inside the main storage were $19.1∼20.1^{\circ}C$ and 53.0∼63.4%. We isolated fungi and classified into 8 genus 13species fungi and selected four fungi having high cellulotic activity such as Alternaria brassicae KCPRI 9202, Aspergillus niger KCPRI 9205, Aspergillusversicolor KCPRI 9206, Penicillium adametzi KCPRI 9208. These fungi were examined on the posibility of collections being damaged under current conservation al environment in the museum. KCPRI 9208 was non-tonophilic fungus and other were facutative tonophilic fungi. These showed maximal cellulotic activity of enzymeshaking culture at pH 5.0∼5.5 for 4 and 5 days. In proprtion to the period damaged, cellulase activity for paper damaged artifically with growing worse of material. As are sult cellulotic activity by fungi increased.

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Estimation of the optimal heated inlet air temperature for the beta-ray absorption method: analysis of the PM10 concentration difference by different methods in coastal areas

  • Shin, So Eun;Jung, Chang Hoon;Kim, Yong Pyo
    • Advances in environmental research
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    • 제1권1호
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    • pp.69-82
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    • 2012
  • Based on the measurement data of the particulate matter with an aerodynamic diameter of less than or equal to a nominal 10 ${\mu}m$ (PM10) by the ${\beta}$-ray absorption method (BAM) equipped with an inlet heater and the gravimetric method (GMM) at two coastal sites in Korea, the optimal inlet heater temperature was estimated. By using a gas/particle equilibrium model, Simulating Composition of Atmospheric Particles at Equilibrium 2 (SCAPE2), water content in aerosols was estimated with varying temperature to find the optimal temperature increase to make the PM10 concentration by BAM comparable to that by GMM. It was estimated that the heated air temperature inside the BAM should be increased up to $35{\sim}45^{\circ}C$ at both sites. At this temperature range, evaporation of volatile aerosol components was minor. Similar ($30{\sim}50^{\circ}C$) temperature range was also obtained from the calculation based on the absolute humidity which changed with ambient absolute humidity and chemical composition of hygroscopic species.