• 제목/요약/키워드: Atmospheric

검색결과 12,413건 처리시간 0.036초

실효온도차법에 의한 최대열부하계산용 일사 대기투과율 (The Solar Atmospheric Transmittance Data for Peak Cooling Load Calculation using ETD Method)

  • 김두천;서진석
    • 설비공학논문집
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    • 제4권4호
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    • pp.316-322
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    • 1992
  • A simplified TAC method was developed for the selection of solar atmospheric transmittance data fundamental to the calculation of design solar radiation for the peak cooling load calculation using ETD method. The summer and autumn solar atmospheric transmittance data of the 11 major cities in Korea were obtained. Based on the simplified TAC method, the atmospheric transmittance data were selected by the TAC 2.5% of July instead of the TAC 2.5% of June through September for summer and the TAC 5.0% of October instead of the TAC 2.5% of October and November for autumn. Results show that the atmospheric transmittance data at solar noon were in the range of 0.61-0.66 for summer and 0.78-0.82 for autumn except for Pusan and Incheon.

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ATMOSPHERIC REFRACTION EFFECTS ON LAMOST

  • SUN AIQUN;Hu JINGYAO
    • 천문학회지
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    • 제29권spc1호
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    • pp.397-398
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    • 1996
  • Large field spectrographs are severely influenced by atmospheric refraction. LAMOST is a large field multi-object spectroscopy telescope with $5^{\circ}$ field of view, f/5 focus ratio and 20m focal length. There will be 4000 fibers simultaneous on it's $\phi$1.75m focal plane. Here we discuss the atmospheric refraction effects on LAMOST in two hands. One is the effect of differential refraction across the field, another is the effect of atmospheric dispersion. According to the calculation, we find that: 1. The largest deviation from center within the field is 4.;32" during a 1.5-hour integration at $80^{\circ}$ declination. 2. The directions of deviation are complex, so the deviations can't be decreased by rotating the field. We also give out the atmospheric dispersions.

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대기확산의 수치모의에서 SST 효과 (SST Effect upon Numerical Simulation of Atmospheric Dispersion)

  • 이화운;원경미;조인숙
    • 한국대기환경학회지
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    • 제15권6호
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    • pp.767-777
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    • 1999
  • In the coastal region air flow changes due to the abrupt change of surface temperature between land and sea. So a numerical simulation for atmospheric flow fields must be considered the correct fields of sea surface temperature(SST). In this study, we used variables such as latent heat flux, sensible heat flux, short and long wave radiation of ocean and atmosphere which exchanged across the sea surface between atmosphere and ocean model. We found that this consideration simulated the more precise SST fields by comparing with those of the observated results. Simulated horizontal SST differences in season were 2.5~4$^{\circ}C$. Therefore we simulated the more precise atmospheric flow fields and the movement and dispersion of the pollutants with the Lagrangian particle dispersion model. In the daytime dispersion pattern of the pollutants emitted from ship sources moved toward inland, in the night time moved toward sea by land/sea breeze criculation. But air pollutants dispersion can be affected by inland topography, especially Yangsan and coastal area because of nocturnal wind speed decrease.

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폭염이 일사망자수에 미치는 영향에 관한 연구 (A Study on the Influence of Extreme Heat on Daily Mortality)

  • 박종길;정우식;김은별
    • 한국대기환경학회지
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    • 제24권5호
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    • pp.523-537
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    • 2008
  • In Korea, the global warming leads to more frequent high temperature region. increasing the need for research into physical damage caused by high temperature. We therefore analyzed the differences of mortality, caused by extreme heat, among gender and age. We also examined the trend of mortality from high temperature-sensitive diseases. Women are more affected by exposure to high temperature than are men; People over 65 years old have higher mortality rate (1.5 times) than under 65. As for high temperature-related diseases, cerebrovascular disease was the number one cause of death, and chronic lower respiratory disease and cardiovascular disease followed.

연속 대기압 플라즈마를 처리한 폴리에스테르 섬유의 표면 특성 (Surface-Properties of Poly(Ethylene Terephthalate) Fabric by In-line Atmospheric Plasma Treatments)

  • 권일준;박성민;구강;송병갑;김종원
    • 한국염색가공학회지
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    • 제19권4호
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    • pp.38-46
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    • 2007
  • Surface properties of the plasma treated fabric were changed while maintaining its bulk properties. Surface of plasma treated fabric take charge of enhanced adhesion by surface etching, surface activity. The water repellency coating Poly(Ethylene Terephthalate) fabric was treated with atmospheric pressure plasma using various parameters such as Argon gas, treatment time, processing power. Morphological changes by atmospheric pressure plasma treatment were observed using field emmission scanning electron microscopy(FE-SEM) and the zeta-potential measurement, contact angle measurement equipment. At the atmospheric pressure plasma treatment time of 150 sec, the power of 800W, the best wettability and peel strength were obtained. And we confirmed the possibility of industrial application by using atmospheric plasma system.

10m 타워 플럭스자료의 품질검증과 활용 방안 (Quality Control and Application of 10 m Tower Flux Data)

  • 최태진;홍진규;김준
    • 한국농림기상학회:학술대회논문집
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    • 한국농림기상학회 2001년도 춘계 학술발표논문집
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    • pp.5-7
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    • 2001
  • 수평적으로 균질한 지면 상태에서 에디 공분산 방법을 이용한 지표 플럭스 관측의 수평 규모는 측정 높이의 약 100 ∼ 200배이다(예, 최태진 등, 1999). Bottom-up 입장에서, 이 수평 규모는 지면 과정을 포함한 수치예보 모형이나 보다 큰 규모의 모형의 격자 간격보다 상당히 작다. 또한 실질적으로 자연 상태의 지면 조건은 엄밀한 의미에서 균질하지 않으며, 특히 우리나라의 경우는 지면 불균질성이 뚜렷이 나타난다.(중략)

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A spectroscopic study of the effect of humidity on the atmospheric pressure helium plasma jets

  • Han, Duksun
    • Current Applied Physics
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    • 제18권11호
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    • pp.1375-1380
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    • 2018
  • Atmospheric-pressure plasma has a great potential in many applications due to its simplicity rather than low pressure plasmas. In material processing, biomedical applications, and many other applications, the input power, gas flow rate, and the geometry of electrode have been mainly considered and studied as important external parameters of atmospheric-pressure plasma control. Besides, since the atmospheric-pressure plasmas are typically generated in an open air, the relative humidity is difficult to control and can change day by day. Therefore, the relative humidity cannot be ignored for plasmas. Thus, in this work, the atmospheric-pressure plasma jet was characterized by changing relative humidity, and it was found that the increase in electron density and OH radicals are due to Penning ionization between helium metastable and water vapors at higher humidity condition.

크린센터 주변 부지 대기확산에 관한 연구 (A study on the atmospheric diffusion of land around the clean center)

  • 최홍주;전용한
    • Design & Manufacturing
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    • 제15권2호
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    • pp.49-55
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    • 2021
  • In this study, CALPUFF, a three-dimensional atmospheric diffusion model, was used to predict the degree of influence of pollutants generated during clean center operation on surrounding areas. To drive the CALPUFF model, CALMET, a weather field calculation model, was used. Due to the influence of the wind field, air pollutants from the Clean Center diffused in the southeast direction, increasing the distribution area. SOx satisfies atmospheric environmental standards with an annual average value of 0.02 ppm or less NOx satisfies atmospheric environmental standards with an annual average value of 0.03 ppm or less. Dust (PM-10) satisfies atmospheric environmental standards with an annual average value of 50㎍/m3 or less and 24 hours average value of 100㎍/m3 or less. CO satisfies atmospheric environmental standards with an 8 hours average value of 9 ppm or less and an 1 hour average value of 25 ppm or less.

Development of Portable Atmospheric Environment Measurement System using Low Power Wireless Communication

  • Chae, Soohyeon;Kim, Hack-Yoon;Gim, Jangwon
    • 한국정보기술학회 영문논문지
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    • 제10권1호
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    • pp.99-109
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    • 2020
  • As environmental pollution has become severe due to the rapid increase in pollutant generation in the air, measurement, collection, and analysis of atmospheric environment information plays an important role. However, it is difficult to measure the high-resolution and real-time atmospheric environment of the cities and tourist spots with high population mobility only by measuring equipment of stationary measuring stations. Therefore, this paper proposes a portable atmospheric environment measurement system for real-time measurement and monitoring of atmospheric environment information. The proposed system is a portable client with a low-power wireless communication method. It is possible to reliably transmit and receive the measured data through a multi-threaded server to monitor the trend of pollutants in the air in real-time.