• 제목/요약/키워드: Global radiation

검색결과 417건 처리시간 0.026초

달 탐사를 위한 달 표면에서의 무선통신 환경 분석 (Analysis on Wireless Communications Environment at Lunar Surface for Lunar Exploration)

  • 이용민;이병선;안재영
    • 전자공학회논문지
    • /
    • 제51권10호
    • /
    • pp.50-54
    • /
    • 2014
  • 본 논문에서는 달 표면에서의 무선통신에 영향을 미칠 수 있는 달의 내, 외부 요인으로서 온도, 우주방사선, 먼지입자 등에 의한 무선통신 환경 및 통신 임무장비에 대한 영향을 분석하였으며, 또 다른 영향 요인으로서 유성충돌, 달에서의 지진활동, 달의 지자계 분포 등에 대해서도 고찰하였다. 본 논문에서 제시된 결과는 향후 국내 달 탐사 프로젝트에서 달에서의 무선통신시스템 설계에 효과적으로 활용할 수 있는 기초적인 자료로 활용될 것이다.

Near-IR Polarization of the Northeastern Region of the Large Magellanic Cloud

  • Kim, Jaeyeong
    • 천문학회보
    • /
    • 제42권2호
    • /
    • pp.42.2-42.2
    • /
    • 2017
  • The Large Magellanic Cloud (LMC) is a unique target to study the detail structures of molecular clouds and star-forming regions, due to its proximity and face-on orientation from us. Most part of the astrophysical subjects for the LMC have been investigated, but the magnetic field is still veiling despite its role in the evolution of the interstellar medium (ISM) and in the main force to influence the star formation process. Measuring polarization of the background stars behind interstellar medium allows us to describe the existence of magnetic fields through the polarization vector map. In this presentation, I introduce the near-infrared polarimetric results for the $39^{\prime}{\times}69^{\prime}$ field of the northeastern region of the LMC and the N159/N160 star-forming complex therein. The polarimetric observations were conducted at IRSF/SIRPOL 1.4 m telescope. These results allow us to examine both the global geometry of the large-scale magnetic field in the northeastern region and the close structure of the magnetic field in the complex. Prominent patterns of polarization vectors mainly follow dust emission features in the mid-infrared bands, which imply that the large-scale magnetic fields are highly involved in the structure of the dust cloud in the LMC. In addition, local magnetic field structures in the N159/N160 star-forming complex are investigated with the comparison between polarization vectors and molecular cloud emissions, suggesting that the magnetic fields are resulted from the sequential formation history of this complex. I propose that ionizing radiation from massive stellar clusters and the expanding bubble of the ionized gas and dust in this complex probably affect the nascent magnetic field structure.

  • PDF

대학 건물에 적용한 열 차단 필름이 냉방부하에 미치는 영향 평가 (The Evaluation of Cooling Load by The Window Film Insulation in College Building)

  • 김석현;강수현;유시완;조영흠
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
    • /
    • pp.549-552
    • /
    • 2012
  • Recently the world is trying to reduce carbon emissions for global warming. Reducing use of fossil fuels can decrease carbon emission. In this reason the construction field has tried to reduce the use of fossil fuels relating to heating and cooling of buildings. An energy loss through the window system is about 10 to 30 percent of energy consumption of the whole building. The use of window film insulation is increasing to control the heat loss at the windows. The window film insulation absorbs solar radiation and makes the surface temperature of windows high. In this study, window surface temperature is measured, and an impact on indoor air is identified after attaching window film insulation. Finally, we found that cooling load decreases through simulation.

  • PDF

도로변 가로녹지 유형이 기상에 미치는 영향 (A Study on the Temperature Reduction Effect of Street Green Area)

  • 김정호;최원준;윤용한
    • 한국환경과학회지
    • /
    • 제26권12호
    • /
    • pp.1363-1374
    • /
    • 2017
  • Global climate change caused by industrialization has caused abnormal weather conditions such as urban temperatures and tropical nights, urban heat waves, heat waves, and heavy rains. Therefore, the study tried to analyze climate conditions and weather conditions in the streets and analyze climate factors and meteorological factors that lead to inconvenience to citizens. In the case of trees, the overall temperature, surface temperature, solar irradiance, and net radiation were measured low, and the temperature was lower in the Pedestrian road than in roads. The dry bulb temperature, the black bulb temperature, and the wet bulb temperature for the thermal evaluation showed the same tendency. In the case of thermal evaluation, there was a similar tendency to temperature in WBGT, MRT, and UTCI, and varied differences between types. Although the correlation between the meteorological environment and the thermal environment showed a statistically significant significance, the difference between the measured items was not significant. The study found that the trees were generally pleasant to weather and thermal climate in the form of trees, and the differences were mostly documented.

정규관측자료와 GPS 연직누적 수증기량을 이용한 안개에 대한 비교연구 (Comparative Research of Fog Using the Regular Observation and GPS Integrated Water Vapor)

  • 이재원;조정호;백정호;박종욱;박지업
    • 대기
    • /
    • 제18권4호
    • /
    • pp.417-427
    • /
    • 2008
  • In this paper, we analyzed the physical and thermodynamic characteristics of fog by using the integrated water vapor (IWV) from Global Positioning System (GPS) networks and the regular observation data of meteorological stations in GPS sites. The cases of a radiation and an advection fog were selected as samples, the conversions of water substance from the water vapor to cloud water in fog were detected by the Bulk Water-Continuity Model, and the pattern analysis is adapted on GPS IWV, temperature, wind and relative humidity. Under the specific hypothesis (saturation and stable), GPS IWV could detect quantitatively the phase changing between the water vapor and cloud water content with condensation/evaporation during the formation and dissipation of fog. After it reaches to the saturation, the relative humidity can be a limited indicator for fog. However, GPS IWV can detect the status change of fog even after the saturation. It has indicated that GPS IWV could be a new observing technique for the processes of the fog formation and the dissipation.

Space Physics Sensor on KOMPSAT-1

  • Min, Kyoung-Wook;Choi, Young-Wan;Shin, Young-Hoon;Lee, Jae-Jin;Lee, Dae-Hee;Kim, Jhoon
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.355-360
    • /
    • 1998
  • A small package of plasma instruments, Space Physics Sensor, will monitor the space environment and its effects on microelectronics in the low altitude region as it operates on board the KOMPSAT-1 from 1999 over the maximum of the solar cycle 23. The Space Physics Sensor (SPS) consists of two parts: the Ionospheric Measurement Sensor (IMS) and the High Energy Particle Detector (HEPD). IMS will make in situ Measurements of the thermal electron density and temperature, and is expected to provide a global map of the thermal electron characteristics and the variability according to the solar and geomagnetic activity in the high altitude ionosphere of the KOMPSAT-t orbit. HEPD will measure the fluxes of high energy protons and electrons, monitor the single event upsets caused by these energetic charged particles, and give the information of the total radiation dose received by the spacecraft. The continuous operation of these sensors, along with the ground measurements such as incoherent scatter radars, digital ionosondes and other spacecraft measurements, will enhance our understanding of this important region of practical use for the low earth orbit satellites.

  • PDF

수치 지형인자를 활용한 토양수분분포 예측 (Prediction of Soil Distribution Using Digital Terrain Indices)

  • 이학수;김경현;한지영;김상현
    • 한국수자원학회논문집
    • /
    • 제34권4호
    • /
    • pp.391-401
    • /
    • 2001
  • 토양수분의 공간적 분포를 예측하기 위하여 지표면 곡률관련인자, 지형흐름인자, 태양에너지 복사인자들을 계산하였다. GPS와 토양수분측정기를 활용한 산지유역에서의 토양수분측정은 토양수분의 공간적 분포자료의 구축을 가능하게 했다. 측정된 토양수분자료와 토양수분 추정인자 사이의 상관관계를 분석하였다. 다중회귀분석을 통한 토양수분 추정인자와 토양수분의 공간적 분포상황에 대한 검토는 수치고도모형(DEM)의 분석을 통한 토양수분 추정능력의 가능성과 한계성을 보여주었다.

  • PDF

과불화탄소 제거를 위한 플라즈마 워터젯 스크러버 개발 (Development of a Plasma Waterjet Scrubber for the Reduction of PFCs)

  • 이채홍;전영남
    • 한국대기환경학회지
    • /
    • 제26권6호
    • /
    • pp.624-632
    • /
    • 2010
  • Perfluorocarbons (PFCs) are widely used in semiconductor industry. These gases need to be removed efficiently because of their strong absorption of infrared radiation and long atmospheric lifetimes which cause the global warming effect. To destruct $CF_4$, a waterjet gliding arc plasma was designed and manufactured. The highest $CF_4$ destruction showed at waterjet plasma case, compared to plasma discharge only or water scrubber only, respectively. In addition, it could be known that the $CF_4$ destruction should be associated with the electron and OH radicals. The operating conditions such as waterjet flow rate, initial $CF_4$ concentration, total gas flow rate, specific energy input were investigated experimentally using a plasma waterjet scrubber. Through the parametric studies, the highest $CF_4$ destruction of 94.5% was achieved at 0.2% $CF_4$, 2.1 kJ/L SEI, 20 L/min total gas flow rate and 18.5 mL/min waterjet flow rate.

Comparative study on Hsp25 expression in Mongolian gerbil and mouse cerebellum

  • Lee, Heang-Yeon;Kim, Seong-Hwan;Lee, Jae-Bong;Shin, Chang-Ho
    • 한국동물위생학회지
    • /
    • 제29권4호
    • /
    • pp.469-482
    • /
    • 2006
  • The term 'heat shock protein (Hsps)' was derived from the fact that these proteins were initially discovered to be induced by hyperthermic conditions. In response to a range of stressful stimuli, including hyperthermia, immobilization, UV radiation, amino acid analogues, arsenite, various chemicals, and drugs the mammalian brain demonstrates a rapid and intense induction of the heat shock protein. Moreover, Hsps were expressed on the various pathological conditions including trauma, focal or global ischemia, hypoxia, infarction, infections, starvation, and anoxia. Especially, Hsp25 has a protective activity, facilitated by the ability of the protein to decrease the intracellular levels of reactive oxygen species (ROS) as well as its chaperone activity, which favors the degradation of oxidized proteins. Recently, it has clearly demonstrated that Hsp25 is constitutively expressed in the adult mouse cerebellum by parasagittal bands of purkinje cells in three distinct regions, the central zone (lobule VI-VII) and nodular zone (lobule IX-X), and paraflocculus. The Mongolian gerbil has been introduced into stroke study model because of its unique brain vasculature. There are no significant connections between the basilarvertebral system and the carotid system. This anatomy feature renders the mongolian gerbil susceptible to forebrain ischemia-induced seizure. The present study is designed to examine the pattern of Hsp25 expression in the cerebellum of this animal in comparison with that in mouse.

현대 사회의 과학 논쟁 주제에 대한 초등 교사의 인식 (The Understanding of Elementary School Teachers on the Current Science Issues)

  • 전영석
    • 한국초등과학교육학회지:초등과학교육
    • /
    • 제27권2호
    • /
    • pp.134-143
    • /
    • 2008
  • We investigated the understanding of elementary school teachers on the current science issues. As a first step of the research, we choose 10 science issues which are influencing current society. Then we asked 119 elementary school teachers in Seoul, Inchon and Daejeon how important they think and how much they know the issues. As a result, we found that almost elementary school teachers know much on alternative energy, atomic bomb, nuclear power generation and global warming while they less know about high technology as Korean supersonic trainer($T-5^{TM}$) and Synchrotron radiation accelerator. Also we know that teachers take an interest on the articles about current science issues only for a while and forget to study on the issues for themselves. It is more important than whatever for the teachers to have exact understanding on current science issues in order to make civil society by acquiring the science literacy. Therefore elementary teachers and preliminary teachers should have a chance to study on current science issues. We suggest that teacher communities should be supported to improve the competency by cooperation.

  • PDF