• 한국전자파학회지:전자파기술
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• 제4권3호
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• pp.37-44
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• 1993

GEO 통신위성을 운용하는 지구국 안테나는 매년 춘추분 경에 태양잡음 간섭을 받는다. 이런 현상들도 대기 권내에서 광선의 굴절로 영향을 받게된다. 따라서 이론적인 태양잡음간섭 예측시간이 실제 간섭이 발생하는 시 간과 잘 맞지 않는다. 이 연구에서는 광선의 굴절 현상과 지구국 안테나의 주 반사경의 크기, 위성과 지구국 안 테나가 이루는 앙각을 고려하여 설제 태양잡음 간섭시간을 해석하였다. 또한 95년도에 발사될 무궁화호 위성을 운용할 경우 야기 될 수 있는 대기권 굴절 현상은 무시될 수 있음을 증명하였다. 본 연구의 결과와 국내 위성 지구국서 실제로 측정한 태양잡음 간섭 시간과 비교 하였으며 두 결과가 잘 맞는다

• 한국포장학회지
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• 제26권1호
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• pp.19-23
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• 2020

Al-laminated packaging film incorporating ascorbic acid or tocopherol at inner food contact layer was tested in the potential to improve antioxidative preservation of powdered infant formula under CO₂-enriched atmosphere. Product of 200 g was packaged with the packaging film containing 0.3% antioxidant in sealant layer of low density polyethylene and stored at 30℃ for 286 days with periodic measurement of package atmosphere and product's quality attributes. The CO₂-flushed package resulted in shrinkage of tight contact between the product and the film not allowing gas sampling of package atmosphere after 140 days. Package of tocopherol-incorporated film allowed some ingress of oxygen after 112 days presumably due to its weakening of heat-seal area. The increased oxygen concentration in the tocopherol-added film package led to the concomitant increase of peroxide value, an index of lipid oxidation. On the other hand, packaging of ascorbic acid-added film pouch could suppress lipid oxidation marginally in consistent manner compared to control package without any antioxidant.

• 한국군사과학기술학회지
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• 제11권5호
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• pp.84-91
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• 2008

The spectral radiance received by a remote sensor at a given temperature and wavelength region is consisted of the self-emitted component directly from the object surface, the reflected component of the solar irradiation at the object surface, and the scattered component by the atmosphere without ever reaching the object surface. The IR image of a ship is mainly affected by location, meteorological condition(atmosphere temperature, wind direction and velocity, humidity etc.), atmospheric transmittance, solar position and ship surface temperature etc. Computer simulations for prediction of the IR signatures of ships are very useful to examine the effects of various meteorological conditions. In this paper, we have acquired the IR signature for different meteorological conditions by using two different computer programs. The numerical results show that the IR image contrast as compared to the background sea considering the atmosphere temperature and wind velocity.

• 자원환경지질
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• 제16권2호
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• pp.79-81
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• 1983

The effeet of the mass of the earth's atmosphere for gravity is studied. The computed correction value of the air mass effect is g=+0.86-0.0978 h (km) mgal and has always positive sign. In comparision with usual gravity works. this value is relatively large. So that, all gravity works always carry out this correction.

• 우주기술과 응용
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• 제3권4호
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• pp.301-321
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• 2023

The Journal of Astronomy and Space Sciences (JASS) has published research papers on a range of topics since its initial publication in 1984, giving space science researchers a platform. In this paper, we reviewed recent publications (2019-2023) that deal with the space environment. In the space environment field, we reviewed 37 papers published in JASS during this time, covering research topics such as the sun, magnetosphere, ionosphere, atmosphere, and space radiation. We hope that researchers in the field will make use of this in the future as it will allow us to share the most recent trends in the field of space environment research that is currently underway.

• 한국식품저장유통학회지
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• 제1권2호
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• pp.125-131
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• 1994

• 천문학논총
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• 제15권spc2호
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• pp.65-71
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• 2000

We have investigated the numerical methods to calculate model atmosphere for the analysis of spectral lines emitted from the sun and stars. Basic equations used in our calculations are radiative transfer, statistical equilibrium and charge-particle conservations. Transfer equation has been solved to get emitting spectral line profile as an initial value problem using Adams-Bashforth-Moulton method with accuracy as high as 12th order. And we have calculated above non linear differential equations simultaneously as a boundary value problem by finite difference method of 3 points approximation through Feautrier elimination scheme. It is found that all computing programs coded by above numerical methods work successfully for our model atmosphere.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.840-842
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• 2003

Recent satellite data have revealed a correlation between the Sun’s activities and the Earth’s atmosphere . Many scientists have been conjectured a more direct connections between solar variability and the Earth’s atmosphere from satellite data analysis. During solar storms, more energetic particles reach the Earth’s atmosphere and this phenomenon have effects on the Earth’s atmospheric environment. Consequently, scientists suggest that these variations will affect a global climate change. In this study, we investigate the confirmative research results of atmospheric effects due to solar activities, especially solar storms.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2011년도 한국우주과학회보 제20권1호
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• pp.30.1-30.1
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• 2011

We present construction of 3D Earth optical Model for in-orbit performance prediction of L1 halo orbiting earth remote sensing instrument; the Albedo Monitor and Radiometer (Amon-Ra) using Integrated Ray Tracing (IRT) computational technique. The 3 components are defined in IRT; 1) Sun model, 2) Earth system model (Atmosphere, Land and Ocean), 3)Amon-Ra Instrument model. In this report, constructed sun model has Lambertian scattering hemisphere structure. The atmosphere is composed of 16 distributed structures and each optical model includes scatter model with both reflecting and transmitting direction respond to 5 deg. intervals of azimuth and zenith angles. Land structure model uses coastline and 5 kinds of vegetation distribution data structure, and its non-Lambertian scattering is defined with the semi-empirical "parametric kernel method" used for MODIS (NASA) missions. The ocean model includes sea ice cap with the sea ice area data from NOAA, and sea water optical model which is considering non-Lambertian sun-glint scattering. The IRT computation demonstrate that the designed Amon-Ra optical system satisfies the imaging and radiometric performance requirement. The technical details of the 3D Earth Model, IRT model construction and its computation results are presented together with future-works.

• 한국재료학회지
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• 제11권10호
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• pp.895-899
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• 2001

Electrical properties of porous $BaTiO_3-based$ ceramics were investigated from the viewpoint of adsorbed oxygen. Namely, the effects of heat-treatment temperature ($450-600^{\circ}C$) and measuring atmosphere (oxygen and nitrogen) on the PTCR characteristics of the porous $BaTiO_3-based$ ceramics were investigated. It was found that the PTCR characteristics of the porous $BaTiO_3-based$ ceramics was developed at $\geq$55$0^{\circ}C$, and the magnitude of the PTCR characteristics increased with increasing heat-treatment temperature. It was also found that the magnitude of the PTCR characteristics in the porous $BaTiO_3-based$ ceramics increased in oxygen atmosphere, whereas decreased in nitrogen atmosphere during heating and cooling.