• 제목/요약/키워드: Field Environment

검색결과 8,421건 처리시간 0.031초

진공환경에서 수평 웨이퍼 표면으로의 입자침착 해석 (Analysis on Particle Deposition onto a Horizontal Semiconductor Wafer at Vacuum Environment)

  • 유경훈
    • 대한기계학회논문집B
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    • 제26권12호
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    • pp.1715-1721
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    • 2002
  • Numerical analysis was conducted to characterize the gas flow field and particle deposition on a horizontal freestanding semiconductor wafer under the laminar flow field at vacuum environment. In order to calculate the properties of gas, the gas was assumed to obey the ideal gas law. The particle transport mechanisms considered were convection, Brownian diffusion and gravitational settling. The averaged particle deposition velocities and their radial distributions fnr the upper surface of the wafer were calculated from the particle concentration equation in an Eulerian frame of reference for system pressures of 1 mbar~1 atm and particle sizes of 2nm~10$^4$ nm(10 ${\mu}{\textrm}{m}$). It was observed that as the system pressure decreases, the boundary layer of gas flow becomes thicker and the deposition velocities are increased over the whole range of particle size. One thing to be noted here is that the deposition velocities are increased in the diffusion dominant particle size range with decreasing system pressure, whereas the thickness of the boundary layer is larger. This contradiction is attributed to the increase of particle mechanical mobility and the consequent increase of Brownian diffusion with decreasing the system pressure. The present numerical results showed good agreement with the results of the approximate model and the available experimental data.

수위변동에 따른 갯벌의 물리적 환경특성의 변화 (Variation of Physical Characteristic of Tidal Flat's Environment by Water Level Change)

  • 박종화
    • 한국환경복원기술학회지
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    • 제2권3호
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    • pp.1-9
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    • 1999
  • This paper described the results of the characteristics of the near-bottom flow and field analysis of the tidal flats sediment. It was the aim of this paper to grasp current flow of tidal flat's environment and influence factor for environmental change forecast of tidal flats. Field measurement of water velocity, water elevation, bed materials test, and temperature distribution of tidal flat were conducted. Thereafter, current flow, turbidity and temperature distribution of tidal flat sediment have been discussed. The field research results showed that the fluctuating velocity near the seabed before and after its appearance at low tide was strongly affected by the wind wave. The resuspension of the sea-bottom sediment took place with great intensity before and after the appearance of the seabed at low tide. Both the sea water level and the weather condition were a significant influential factors. Such as, temperature and turbidity just on the surface and the shallow layer of seabed sediments were varied largely with time and weather conditions, but that its deeper layers was almost constant. Temperature on the seabed sediments was strongly influenced by irradiance and water depth. The temperature variation of the tidal flat and the variation characteristics of the current flow and turbidity depend greatly on the inhabiting environment of the tidal flat benthic organism.

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하절기 복사환경 관측을 통한 수목과 일사차폐 막 구조물의 자연냉각효과 (Analysis of Passive Cooling Effect of Membrane Shading Structure and the Tree by Field Observations in the Summer)

  • 최동호;이부용
    • 한국태양에너지학회 논문집
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    • 제27권4호
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    • pp.137-146
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    • 2007
  • This study is about the passive cooling effects of three outdoor solar shading facilities as trees, pergola with wistaria vine and membrane shading structure, which are expected to provide cool spots in the summer. Field observations of measuring thermal environment of selected facilities is executed. Thermal environment measuring was categorized as short wave radiation, long wave radiation, net radiation, globe temperature, surface temperature measured by infrared camera. Heat transfer mechanism is analyzed with overall data from field measurement. Results from this study are as below; 1) Radiation balance measured on shaded surface under membrane shading structure was 17%($86W/m^2$) of the unshaded surface radiation balance($511W/m^2$). 2) Surface temperature comparison between vegetation and membrane of the shading structure is performed at 3 o'clock in the afternoon. Surface temperature of vegetation was same as air temperature and that of membrane was $5^{\circ}C$ higher than air temperature. Vegetation transpiration is considered as the causing factor which make those differences. 3) Results from this study could be used as fundamental data for reducing heat island phenomena and continuos research on this subject would be needed.

전원고립형 공동주택단지의 녹환경 평가에 관한 연구 (A Study on the Greenery Environment Evaluation of the Apartment House Complexes Encircled by the Fields)

  • 김익환;장한섭;김영민
    • 한국주거학회논문집
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    • 제18권2호
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    • pp.59-63
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    • 2007
  • In the suburbs near the capital area in Korea, many apartment house complexes are dotted that encircled by field. These apartment house complexes encircled by field, have not park and are abutting on the field, unlike large scale new town. This study is aimed to clear the characteristic of field around these apartment house complexes, consists in development the suburbs near the capital area. As a method of study we conducted greenery evaluation from view of Inhabitant by questionnaire survey. We concluded as follows: inhabitants attach importance to the nature around apartment house complex when move into that; inhabitants are satisfied and feel nature about the field; inhabitants tend to take field as a sight; inhabitants need low-rise development for harmony with field.

A Non-contact Detection Method for Smelting in Submerged Arc Furnace based on Magnetic Field Radiation

  • Liu, WeiLing;Chang, XiaoMing
    • Journal of Magnetics
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    • 제21권2호
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    • pp.204-208
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    • 2016
  • This paper demonstrates the key parameter detection for smelting of submerged arc furnace (SAF) based on magnetic field radiation. A magnetic field radiation model for the inner structure of SAF is established based on relative theory of electromagnetic field. A simple equipment of 3D magnetic field detection system is developed by theoretical derivation and simulation. The experiments are carried out under the environment of industrial field and AC magnetic field generated by electrode currents and molten currents in the furnace is reflected outside of the furnace. The experimental results show that the key parameters of smelting including the position of electrode tip, the length of electric arc, and the liquid level of molten bath can be achieved. The computed tomography for SAF can be realized by the detection for smelting.

패션스페셜리스트의 현황 및 비전에 관한 연구 - 멀티미디어분야를 중심으로- (A Study on the Status of Affairs and Vision of Fashion Specialists - Focusing on the Field Related to Multi-Media -)

  • 박송애
    • 한국의상디자인학회지
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    • 제9권2호
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    • pp.179-192
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    • 2007
  • This study is to search for a new area and a new kind of occupation for fashion in the field of multi-media such as a movie, drama, mass-culture and advertisement, as a basic investigation to improve a potential of a development of fashion in the future, to keep in step with the trend of the changes under the environment of cultural renovation. In this reports, the field and vision of new contents in fashion will be proposed. The definition and environment of multi-media were examined, and various kinds and work areas of new fashion specialists were defined. 12 professionals in each fields relative to multi-media were selected and the status of affairs, problems and requirements of fashion specialists were investigated through the in-depth interviews with them. Finally new fields and visions were suggested on it's future course. The kind of fashion-specialist on the field related to multi-media were like this: 1. Fashion-stylist, Art-director and Image-maker for star on the field of Video industry. 2. Fashion-illustrator for making animation-game character, Avatar fashion product designer and Internet shopping buyer for Online-business industry. 3. Fashion PR director, Fashion-photo stylist for Advertisement industry. 1 classified new field on the field related to multi-media as the above, and I researched the role of specialist in each field and the status of affairs and vision.

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A Study on the Site analysis of Jongmyo area -With Feng-shui theory and Geomagnetic Field

  • Han, Jong-Koo;Park, Tong-So
    • KIEAE Journal
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    • 제2권4호
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    • pp.41-47
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    • 2002
  • East Asian explain the changes of substance happened on earth and those of human life with the conceptual frame of "Gi-ki"(地氣; earth vital energy) and organize them by the system of "Feng-shui(風水) theory. The core of Feng-shui theory is reading the expression of the nature and feeling the Gi-ki from the expression. One of the properties of the earth is that the earth has a magnetic field associated with it- the Geomagnetic field. The geomagnetic field is produced by a combination of the effects of electric currents in the earth's liquid core, the magnetization of crustal rocks, external electric current systems that surround the earth and currents induced in the outer layers of the earth by magnetic field variations. The sameness of logic between Feng-shui and geopathic zones is that both are concerned with the discrimination of site and the energy of places, in other words both disciplines are concerned with how the environment can influence people. In this context the operation of Gj-ki can be related with the effect caused by geomagnetic field on site. In this study Jongmyo(宗廟), one of the representative traditional architecture in Korea is selected because the site selection and building layout follows Feng-shui faithfully according to Taejo silok (太祖實錄, Annals of King Taejo). Observing the landforms surrounding Jongmyo, Jongmyo is apparently located in auspicious places named Gumge Poranhyoeng(金鷄抱卵形, a Feng-shui landscape of golden hen sitting on eggs). The geomagnetic investigation of Jongmyo shows that the geomagnetic values of Toekan(the space near Hyeol) are relatively high and uniform and those of Sangweoldae and Haweoldae are decreased in accordance with the distance. The result shows that there is possibility that Feng-shui has scientific basis related with geomagnetic field. Feng-shui theory can suggest a direction for designing the sustainable building for living with nature.

PRELIMINARY REPORT: DESIGN AND TEST RESULTS OF KSR-3 ROCKET MAGNETOMETERS

  • Kim, Hyo-Min;Jang, Min-Hwan;Lee, Dong-Hun;Ji, Jong-Hyun;Kim, Sun-Mi;Son, De-Rac;Hwang, Seung-Hyun
    • Journal of Astronomy and Space Sciences
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    • 제17권2호
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    • pp.317-328
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    • 2000
  • The solar wind contributes to the formation of unique space environment called the Earth's magnetosphere by various interactions with the Earth's magnetic field. Thus the solar-terrestrial environment affects the Earth's magnetic field, which can be observed with an instrument for the magnetic field measurement, the magnetometer usually mounted on the rocket and the satellite and based on the ground observatory. The magnetometer is a useful instrument for the spacecraft attitude control as well as the Earth's magnetic field measurements for the spacecraft purpose. In this paper, we present the preliminary design and test results of the two onboard magnetometers of KARI's (Korea Aerospace Research Institute) sounding rocket, KSR-3, which will be launched four times during the period of 2001-02. The KSR-3 magnetometers consist of the fluxgate magnetometer, MAG/AIM (Attitude Information Magnetometer) for acquiring the rocket flight attitude information, and of the search-coil magnetometer, MAG/SIM (Scientific Investigation Magnetometer) for the observation of the Earth's magnetic field fluctuations. With the MAG/AIM, the 3-axis attitude information can be acquired by the comparison of the resulting dc magnetic vector field with the IGRF (International Geomagnetic Reference Field). The Earth's magnetic field fluctuations ranging from 10 to 1,000 Hz can also be observed with the MAG/SIM measurement.

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강우시 밭의 비점오염물질 유출 특성 (Runoff Characteristics of NPS Pollution on Field in Rainy Season)

  • 원철희;최용훈;신민환;신동석;강동구;최중대
    • 한국물환경학회지
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    • 제27권5호
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    • pp.572-579
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    • 2011
  • We have examined the runoff characteristics of nonpoint source (NPS) in fields. Two monitoring sites were equipped with an automatic velocity meter and water sampler. Monitoring was conducted at fields 1 and field 2 during the rainfall event. Ten rainfall-runoff events were monitored and analyzed during the study period. The results show that runoff occurred if daily rainfall and intensity were higher than 40 mm and 1.6 mm/hr except a few extreme rainfall events with very high intensity. Runoff of field 1 was approximately twice of that of field 2. Event mean concentrations (EMC) and pollution load of analyzed water quality indices were also higher in field 2 than in field 1. Especially, TN load from field 2 was $75.4 mg/m^2$ and was about 5 times higher than that from field 1. Analysis of Pearson correlation coefficient of water quality parameter indicates that besides of TN all items in fields 1 have tight relationship respectively (p < 0.01). But those of fields 2 have a significant (p < 0.05). Estimating units loading of NPS, we suggested that variable such as soil texture, rainfall amount and intensity and slope were needed to be considered from agricultural landuses. The results of this study can be used as a basic data in the development and implementation of total maximum daily loads (TMDL) in Korea.

유니버설디자인을 적용한 고령친화형 운동환경 디자인 가이드라인 (Aging-Friendly Outdoor Exercise Environmental Design Guideline With Universal Design)

  • 이연숙;안창헌;이동주
    • KIEAE Journal
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    • 제12권4호
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    • pp.47-57
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    • 2012
  • The purpose of this study is to develop an aging friendly guideline aging friendly outdoor exercise environment in Universal design aspect. The aim for this guideline is to suggest a creative method to cope with forthcoming aging society and meet the various demands of all park users. Documentary survey and field survey were used to extract notion of universal design and aging friendly design; based from the extracted notions three types of exercise environment were suggested, Small scale, Medium scale and Large scale. The significant of this guideline is as fallow: First, negative aspects of aging friendly design can be eliminated by adopting universal design; therefore the guideline can have social integration aspect. Second, reflected needs of residents can be suggested on the guideline; and it was extracted from documentary survey, PPP UD checklist and field survey. Third, classifying universal design and aging friendly design in one guideline can enhance ability to manage various composition of population. Fourth, by studying young child and old people's likeness and parallel resemblance, design guideline for forthcoming aging society can be suggested. Fifth, from three developed exercise environments, the guideline can be applied into different conditions of location. Sixth, canopy type design model can be very useful for old people.