• Title/Summary/Keyword: Altitude of the sun

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Precision GPS Orbit Determination and Analysis of Error Characteristics (정밀 GPS 위성궤도 결정 및 오차 특성 분석)

  • Bae, Tae-Suk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.4
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    • pp.437-444
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    • 2009
  • A bi-directional, multi-step numerical integrator is developed to determine the GPS (Global Positioning System) orbit based on a dynamic approach, which shows micrometer-level accuracy at GPS altitude. The acceleration due to the planets other than the Moon and the Sun is so small that it is replaced by the empirical forces in the Solar Radiation Pressure (SRP) model. The satellite orbit parameters are estimated with the least-squares adjustment method using both the integrated orbit and the published IGS (International GNSS Service) precise orbit. For this estimation procedure, the integration should be applied to the partial derivatives of the acceleration with respect to the unknown parameters as well as the acceleration itself. The accuracy of the satellite orbit is evaluated by the RMS (Root Mean Squares error) of the residuals calculated from the estimated orbit parameters. The overall RMS of orbit error during March 2009 was 5.2 mm, and there are no specific patterns in the absolute orbit error depending on the satellite types and the directions of coordinate frame. The SRP model used in this study includes only the direct and once-per-revolution terms. Therefore there is errant behavior regarding twice-per-revolution, which needs further investigation.

Evaluation Study of a Double Blind Light Pipe Daylighting System Efficiency and an Illumination Energy Reduction (이중 블라인드 광파이프 주광 조명시스템 효율 및 조명에너지 절감량 평가 연구)

  • Kang, Eun-Chul;Yoo, Seong-Yeon;Lee, Euy-Joon
    • Journal of the Korean Solar Energy Society
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    • v.33 no.1
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    • pp.89-95
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    • 2013
  • A DBLP(Double blind light pipe) daylight system can be installed at a building exterior wall or roof to replace artificial light during the day time. This system was consisted of a double blind light collector, a mirror duct type light transformer and a prism light pipe distributor. The double blinds were used to track the sun's altitude and azimuth movements to collect the sunlight throughout the day. The sunlight collected by the light collector was reflected on the first mirror and the second mirror and sent to the light pipe through the light transformer. The transformer was designed to deliver the sunlight into the light pipe efficiently. The light distributor plays a role in diffusing the sunlight coming in through the light collector to be used for indoor lighting. In this paper, a DBLP system has been designed, installed and tested at a KIER daylighting twin test cell. The DBLP daylighting system was applied to the experimental test cell which has an indoor area of 2.0 m wide ${\times}$ 2.4 m height ${\times}$ 3.8 m length. The experiment was conducted from January 30 to February 27, 2012, under clear skies and partially cloudy skies. Data was collected from 10:00 am to 16:00 pm every 2 minute and the average was calculated for every 30 minute of the data collection to obtain the system efficiency. The results indicated that the DBLP system efficiency was evaluated as 11.67%. The DBLP system indoor illumination energy reduction was predicted as 0.822 kWh/day. This could replace 4 sets of a 32W fluorescent lamp operating 6.4 hours per a day.

In vitro Stimulation of NK Cells and Lymphocytes Using an Extract Prepared from Mycelial Culture of Ophiocordyceps sinensis

  • Sun-Hee Jang;Jisang Park;Seung-Hwan Jang;Soo-Wan Chae;Su-Jin Jung;Byung-Ok So;Ki-Chan Ha;Hong-Sig Sin;Yong-Suk Jang
    • IMMUNE NETWORK
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    • v.16 no.2
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    • pp.140-145
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    • 2016
  • Ophiocordyceps sinensis is a natural fungus that has been valued as a health food and used in traditional Chinese medicine for centuries. The fungus is parasitic and colonizes insect larva. Naturally occurring O. sinensis thrives at high altitude in cold and grassy alpine meadows on the Himalayan mountain ranges. Wild Ophiocordyceps is becoming increasingly rare in its natural habitat, and its price limits its use in clinical practice. Therefore, the development of a standardized alternative is a great focus of research to allow the use of Ophiocordyceps as a medicine. To develop an alternative for wild Ophiocordyceps, a refined standardized extract, CBG-CS-2, was produced by artificial fermentation and extraction of the mycelial strain Paecilomyces hepiali CBG-CS-1, which originated from wild O. sinensis. In this study, we analyzed the in vitro immune-modulating effect of CBG-CS-2 on natural killer cells and B and T lymphocytes. CBG-CS-2 stimulated splenocyte proliferation and enhanced Th1-type cytokine expression in the mouse splenocytes. Importantly, in vitro CBG-CS-2 treatment enhanced the killing activity of the NK-92MI natural killer cell line. These results indicate that the mycelial culture extract prepared from Ophiocordyceps exhibits immune-modulating activity, as was observed in vivo and this suggests its possible use in the treatment of diseases caused by abnormal immune function.

FORMOSAT-2'S EFFECTIVENESS TO TAIWAN'S PUBLIC EDUCATION

  • Chern, Jeng-Shing;Wu, Lance;Liou, Yuei-An
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.959-962
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    • 2006
  • Public education is undoubtedly a very important aspect for a country to develop space program. People have the rights to understand how the tax they paid is being used. This paper addresses the effectiveness of FORMOSAT-2 on public education in Taiwan. As the first remote sensing satellite of the National Space Organization (NSPO) of Taiwan, FORMOSAT-2 is a small satellite of 746 kg mass for two remote sensing missions: Earth and upward lightning observations. The mission orbit is sun-synchronous of 888 km altitude for exactly 14 revolutions per day. For earth observation, the payload is an advanced high resolution remote sensing instrument (RSI) with ground sampling distance (GSD) 2 m in panchromatic (PAN) band and 8 m in four multi-spectral (MS) bands. For upward lightning observation, the payload is an imager of sprites and upper atmospheric lightning (ISUAL). After more than two years of Earth observation started in June 2004, the effectiveness of FORMOSAT-2 images on public education in Taiwan is very promised. Five domestic universities and one private company in Taiwan have signed contracts respectively with NSPO to take the roles of satellite image investigator and distributor. A private company has signed contract with NSPO to generate and provide URMAP (= your map) in its website for general public applications by using FORMOSAT-2 images. The Newtonkids Book Company used FORMOSAT-2 images to publish a kind of calendar for children education purpose. Besides, a science team in National Cheng Kung University (NCKU) is doing the research work on the 3820 (up to 30 June 2006) transient luminous events (TLEs) observed by FORMOSAT-2.

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Design Verification of Environmental Control System by Flow Balance Test (유량평형시험을 통한 환경제어계통 설계 검증)

  • Park, Dong-Myung;Joung, Yong-In;Moon, Woo-Yong;Park, Sung-Sun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.7
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    • pp.608-615
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    • 2012
  • In this study, we analyzed the system impedance of Unmanned Aerial Vehicle avionics bay and Environmental Control System(ECS), and estimated the proper air flow rate to be supplied avionics equipments. As the result of estimation, we evaluated the performance of ECS after analysing the flow balance rate and the air flow rate about each outlet port, and simultaneously decided the flow balance rate after evaluating the thermal substantiality by the thermal analysis of avionics bay. In order to verify the property of analysis result, we conducted the flow balance test using the actual avionics equipments and finally deduced the flow rate to be met system requirements of avionics equipments. Also, as the analysis results, we verified the satisfaction of system requirements at midium altitude condition and proved the performance characteristics of an Environmental Control System(ECS).

A Study on the Daylight Illumination Environment of a Classroom and a Glare Phenomenon on the Blackboard (교실의 주광 조명환경과 철판의 눈부심 현상에 관한 연구)

  • 임윤빈;장우진
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1996.11a
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    • pp.42-48
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    • 1996
  • Glare phenomenon by sun's altitude and strong sunlight make a much visual handicap. And so, it reaches to unreadable situation although enough illumination in the fore site student of a window site and passage site. In school student seat arrange in the order of their height. So, cause the eyesight acuity according to distance is different, eyesight of backseat's student drop 1.0 and less in spite of 1.0, a learning effect reduces rather then that of the fore site student for site and Passage sitestudents. Therefore. in school, the conclusion's alteration of school structure, position's alteration and material quality's improvement of blackboard are needed, should be local lighting in blackboard. Therefore, we think that in other in improve the effect of lesson by the student, the student seats are not given by uniform disposition in the order of their height but change by a specified period.

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Analysis of Digital Terrain Model Display by Comparison of GIS Shaded Relief and Rendering (GIS 음영기복과 렌더링의 비교에 의한 수치지형모형의 표현 분석)

  • Lee, Hyung-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.1
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    • pp.127-136
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    • 2006
  • Shaded relief is used in the analysis of digital terrain model, but accurate shadow zone has not been affirmed on account of idea only shadow of terrain that would be in shadow are shaded. This study is to analyze each display difference of a digital terrain model by grasping the shadow characteristics of terrain and comparing shaded relief function used terrain display of GIS with a rendering technique. After terrain with road in subject area is selected and created to digital terrain model of TIN, shaded relief and rendering according to altitude and azimuth of the sun at 9:00 am and 3:00 pm is applied. As the results, only backward portions of the terrain that is in shadow from the sunlight are shaded in case of shaded relief. The rendering created the shadow, which is cast by terrain features. By these mutual comparison, this study represented data for understanding of shaded relief. And it is expected that the rendering method could be used to analyze sunshine influence.

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Far-ultraviolet Observations of the Comet C/2001 Q4 (NEAT)

  • Lim, Yeo-Myeong;Min, Kyoung-Wook;Seon, K.I.;Han, W.;Edelstein, J.
    • Bulletin of the Korean Space Science Society
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    • 2011.04a
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    • pp.20.1-20.1
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    • 2011
  • We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual-channel imaging spectrograph (S channel 900-1150 ${\AA}$, L channel 1350-1750 ${\AA}$, ${\lambda}/{\Box}{\lambda}$ ~ 550) with large image fields of view (S: $4^{\circ}.0{\times}4'.6$, L: $7^{\circ}.5{\times}4'.3$, angular resolution 5'-10') optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) was observed with a scanning survey mode when it was located around the perihelion between 8 and 15 May 2004. Several important emission lines were detected including S I (1425, 1474 ${\AA}$), C I (1561, 1657 ${\AA}$) and several emission lines of CO $A1{\cap}-X1{\sum}+$ system in the L channel. We estimated QCO = ($2.58\;{\pm}\;0.64)\;{\times}\;1028$ s-1 from the production rate of CO 1510 ${\AA}$. We obtained L-channel image which have map size of $5^{\circ}{\times}5^{\circ}$. The image was constructed for the wavelength band of L-channel (1350-1750 ${\AA}$).We also obtained radial profile of S I, C I, CO with line fitting from central coma.

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Installation and Safety Evaluation of Tracking-type Floating PV Generation Structure (추적식 수상 태양광발전 구조물의 시공 및 안전성 평가)

  • Jang, Min-Jun;Kim, Sun-Hee;Lee, Young-Geun;Woo, Sang-Byock;Yoon, Soon-Jong
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.5 no.1
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    • pp.1-8
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    • 2014
  • Pultruded glass fiber reinforced polymeric plastic (PFRP) and FRP member manufactured by sheet molding compound (SMC) have superior mechanical and physical properties compared with those of conventional structural materials. Since FRP has an excellent corrosion-resistance and high specific strength and stiffness, the FRP material may be highly appreciated for the development of floating-type photovoltaic (PV) power generation system. In this paper, advanced floating PV generation system made of PFRP and SMC is designed. In the design, it includes tracking solar altitude by tilting photovoltaic arrays and tracking solar azimuth by spinning structures. Moreover, the results of the finite element analysis (FEA) are presented to confirm stability of entire structure under the external loads. Additionally, installation procedure and mooring systems in the Hap-Cheon Dam are discussed and the measurement of strain under the actual circumstances is conducted for assuring stability of actually installed structures. Finally, by comparison with allowable stress, appropriate safety of structure is confirmed to operate the system.

Development of Habitat Suitability Index for Habitat Restoration of Class I Endangered Wildlife, Cypripedium guttatum Cw. (멸종위기 야생생물 I 급 털복주머니란 서식지 복원을 위한 서식지 적합성 지수(HSI) 개발)

  • Yoon, Young-Jun;Kim, Sun-Ryoung;Jang, Rae-Ha;Han, Seung-Hyun;Lee, Dong-Jin;Shim, Yun-Jin;Park, Yong-Su
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.4
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    • pp.1-11
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    • 2020
  • This study aimed to develop the HSI (Habitat Suitability Index) model of Cypripedium guttatum. and to verify this model by applying to the candidate sites for replacement habitat. The development of HSI and SI (Suitability Index) model was conducted based on the existing literature, field surveys, and expert opinions for information on ecological habitat characteristics. Seven variables were selected as habitat variables including mean maximum temperature in Jul.-Aug., lighting, slope, altitude, effective soil depth, soil texture, and artificial overexploitation (i.e. protected areas). HSI model was developed for C. guttaum based on these variables. This HSI model showed high applicability to selection and evaluation of replacement habitats for C. guttaum. Our findings could provide the basic information on habitat assessment to prevent the extinction of endangered C. guttatum. However, since there is a limitation that the survey data were insufficient, further field surveys should be conducted on several habitat types to improve the accuracy of the HSI model.