• Title/Summary/Keyword: Observation instrument

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REQUIREMENTS AND FEASIBILITY STUDY OF FPC-G FINE GUIDING IN SPACE INFRARED TELESCOPE, SPICA (대형 적외선 우주망원경 SPICA/FPC-G의 정밀 별추적 요구사항과 타당성 연구)

  • Jeong, Woong-Seob;Lee, Dae-Hee;Pyo, Jeonghyun;Moon, Bongkon;Park, Sung-Joon;Ree, Chang Hee;Park, Youngsik;Han, Wonyong;Nam, Ukwon;Matsumoto, Toshio
    • Publications of The Korean Astronomical Society
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    • v.27 no.5
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    • pp.391-397
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    • 2012
  • The SPICA (SPace Infrared Telescope for Cosmology & Astrophysics) project is a next-generation infrared space telescope optimized for mid- and far-infrared observation with a cryogenically cooled 3m-class telescope. It will achieve the high resolution as well as the unprecedented sensitivity from mid to far-infrared range. The FPC (Focal Plane Camera) proposed by KASI as an international collaboration is a near-infrared instrument. The FPC-S and FPC-G are responsible for the scientific observation in the near-infrared and the fine guiding, respectively. The FPC-G will significantly reduce pointing error down to below 0.075 arcsec through the observation of guiding stars in the focal plane. We analyzed the pointing requirement from the focal plane instruments as well as the error factors affecting the pointing stability. We also obtained the expected performance in operation modes. We concluded that the FPC-G can achieve the pointing stability below 0.075 arcsec which is the requirement from the focal plane instruments.

Analysis of the Thermal Dome Effect from Global Solar Radiation Observed with a Modified Pyranometer

  • Zo, Ilsung;Jee, Joonbum;Kim, Buyo;Lee, Kyutae
    • Current Optics and Photonics
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    • v.1 no.4
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    • pp.263-270
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    • 2017
  • Solar radiation data measured by pyranometers is of fundamental use in various fields. In the field of atmospheric optics, the measurement of solar energy must be precise, and the equipment needs to be maintained frequently. However, there seem to be many errors with the existing type of pyranometer, which is an element of the solar-energy observation apparatus. In particular, the error caused by the thermal dome effect occurs because of the thermal offset generated from a temperature difference between outer dome and inner casing. To resolve the thermal dome effect, intensive observation was conducted using the method and instrument designed by Ji and Tsay. The characteristics of the observed global solar radiation were analyzed by classifying the observation period into clear, cloudy, and rainy cases. For the clear-weather case, the temperature difference between the pyranometer's case and dome was highest, and the thermal dome effect was $0.88MJ\;m^{-2}\;day^{-1}$. Meanwhile, the thermal dome effect in the cloudy case was $0.69MJ\;m^{-2}\;day^{-1}$, because the reduced global solar radiation thus reduced the temperature difference between case and dome. In addition, the rainy case had the smallest temperature difference of $0.21MJ\;m^{-2}\;day^{-1}$. The quantification of this thermal dome effect with respect to the daily accumulated global solar radiation gives calculated errors in the cloudy, rainy, and clear cases of 6.53%, 6.38%, and 5.41% respectively.

Qualitative Research on Behavioral Characteristic of KSA Students That Appear to Observation Recording of Parents and Qualitative Admission Data by CAQDAS (CAQDAS에 의한 부모의 관찰 기록 및 질적 선발 자료에 나타난 한국과학영재학교 학생들의 행동 특성에 관한 질적 연구)

  • Lee, Jeong-Cheol;Kang, Soon-Min;Kim, Dong-Yeol;Huh, Hong-Wook
    • Journal of Gifted/Talented Education
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    • v.20 no.2
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    • pp.427-459
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    • 2010
  • The personal introduction of 2009 academic year Korea Science Academy (KSA) freshman, 143 persons, recommendation that is filled with giftedness cases and observation recording through observing the students by guidance teacher and professor, and Observation recording paper about students that is made by parents, were analyzed in order to investigate behavior characteristics of the Scientifically Gifted by Computer Assisted Qualitative Data Analysis System (CAQDAS). We could divide behavior characteristics of the Scientifically Gifted to 5 main categories by study results. As well as this study may make up for foreign researches and existing researches dependent on quantitative research about behavior characteristics of the Scientifically Gifted, This can be used as a useful data for development of instrument for identifying the scientifically Gifted and teaching-studying program by supporting understand behavior characteristics of the Scientifically Gifted as a specific area of giftedness.

Accuracy evaluation of microwave water surface current meter for measurement angles in middle flow condition (전자파표면유속계의 측정 각도에 따른 평수기 유속 측정 정확도 분석)

  • Son, Geunsoo;Kim, Dongsu;Kim, Kyungdong;Kim, Jongmin
    • Journal of Korea Water Resources Association
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    • v.53 no.1
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    • pp.15-27
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    • 2020
  • Streamflow discharge as a fundamental riverine quantity plays a crucial role in water resources management, thereby requiring accurate in-situ measurement. Recent advances in instrumentations for the streamflow discharge measurement has complemented or substituted classical devices and methods. Among various potential methods, surface current meter using microwave has increasingly begun to be applied not only for flood but also normal flow discharge measurement, remotely and safely enabling practitioners to measure flow velocity postulating indirect contact. With minimized field preparedness, this method facilitated and eased flood discharge measurement in the difficult in-situ conditions such as extreme flood in active ways emitting 24.125 GHz microwave without relying on natural lights. In South Korea, a rectangular shaped instrument named with Microwave Water Surface Current Meter (MWSCM) has been developed and commercially released around 2010, in which domestic agencies charging on streamflow observation shed lights on this approach regarding it as a potential substitute. Considering this brand-new device highlighted for efficient flow measurement, however, there has been few noticeable efforts in systematic and comprehensive evaluation of its performance in various measurement and riverine conditions that lead to lack in imminent and widely spreading usages in practices. This study attempted to evaluate the MWSCM in terms of instrumen's monitoring configuration particularly regarding tilt and yaw angle. In the middle of pointing the measurement spot in a given cross-section, the observation campaign inevitably poses accuracy issues related with different tilt and yaw angles of the instrument, which can be a conventionally major source of errors for this type of instrument. Focusing on the perspective of instrument configuration, the instrument was tested in a controlled outdoor river channel located in KICT River Experiment Center with a fixed flow condition of around 1 m/s flow speed with steady flow supply, 6 m of channel width, and less than 1 m of shallow flow depth, where the detailed velocity measurements with SonTek micro-ADV was used for validation. As results, less than 15 degree in tilting angle generated much higher deviation, and higher yawing angle proportionally increased coefficient of variance. Yaw angles affected accuracy in terms of measurement area.

A Study on the Prevention of Nosocomial Respiratory Infection in Critical Care Nurses (중환자실 간호사의 호흡기병원감염 예방에 관한 연구)

  • Choi Ji-Youn;Park Kyung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.6 no.3
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    • pp.397-413
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    • 1999
  • The purpose of study is to prevent Nosocomial Respiratory Infection after understand the Correlation about Recognition and Performance of Critical Nurses. Data were collected from Critical Nurses 300 persons who has worked in 14 Subsidary Hospitals of University in Seoul and the collection periode is from Nov. 1st, 1997 to Jul. 14th. 1998. There are 40 questions and constructed by 6 Domains which Hand Washing, Suction Management, Airway Management, Respiratory Instrument. Ventilation and Respiratory Intervention. Also, the Data were analized with SPSS program. The obtained results are as follows : (1) The Mean of Recognition for Prevention of Nosocomial Respiratory Infection is 4.649 and by Domains, Respiratory Intervention(4.758), Suction Management (4.669), Airway Management(4.660), Hand Washing(4.651), Ventilation(4.605) and Respiratory Instrument(4.561) according to the Mean. (2) The Mean of Performance for Prevention of Nosocomial Respiratory Infection is 3.991 and by Domains, Respiratory Intervention(4.498), Airway Management (4.107), Hand Washing(4.084), Suction Management(3.898), Respiratory Instrument(3.860) and Ventilation(3.690) according to the Mean. (3) In the Correlation of Recognition and Performance for the Prevention of Nosocomial Respiratory Infection, Hand Washing(r=0.755, p=0.000), Airway Management(r=0.724, p=0.000), Respiratory Intervention(r=0.693, p=0.000) are mentioned significant correlation level. The Performance is good whenever the Recognition is high for Respiratory Instrument(r=0.143, p=0.054) but it's not significant level and Suction Management and Ventilation has no Correlation. (4) In Normal Properties, The Recognition is good(p<.05) when Nurses has plenty Clinical Career, Attendance of the Education and Exclusive Nurse for the Respiratory Infection is in Hospital. The Age is not significant correlation level statistically but represent a little correlation. The Performance is good(p<.05) when Elder Age, Attendance of the Education and the plenty Clinical Career is not significant correlation level statistically but represent a little correlation. Another properties has no menas. According to the results, Suggestion is as follows ; (1) Required Education to advance Recognition and Performance about Prevention of Nosocomial Respiratory Infection for a little clinical career of Nursing and younger Nurses. (2) It needs to analyze Performance about Prevention of Nosocomial Respiratory Infection by observation of research worker.

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Analysis of Measured Vibration Data due to Rock Blasting and Crushing (암반발파 및 파쇄로 인한 진동값 측정과 분석)

  • Moon, Ka-Eun;Rhim, Hong-Chul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.177-178
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    • 2015
  • Various vibration caused by construction vehicles and equipment movement, rock blasting, and crushing obstacle occurs inevitably in construction sites. In this study, we measured the impact of vibration by blasting rock at construction sites, rock crushing, concrete crushing. The measuring instrument was installed in adjacent buildings and observed that blasting vibration differs depending on the charge weight, blasting distance, and the measuring position. The observation was maintained by allowable peak particle velocity standard according to each standards and references.

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Quality Analysis of SAR Image

  • Lee, Young-Ran;Kwak, Sung-Hee;Shin, Dong-Seok;Park, Won-Kyu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.628-630
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    • 2003
  • Synthetic Aperture Radar(SAR) is an active microwave instrument that performs high-resolution observation under almost all weather condition. Research and algorithms have been proposed to process radar signal and to increase the quality of SAR products. In fact, many complicated steps are involved in order to generate a SAR image product. The purpose of this paper is to derive quality assessment procedures and define important test parameters in each procedure inside a SAR processor. Thus those test parameter values indicate the quality of SAR image products and verify the processor's performance. Moreover, required procedures to correct and handle errors which are indicated during the assessment are also presented.

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Analysis on Characteristics of Radiosonde Bias Using GPS Precipitable Water Vapor

  • Park, Chang-Geun;Baek, Jeong-Ho;Cho, Jung-Ho
    • Journal of Astronomy and Space Sciences
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    • v.27 no.3
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    • pp.213-220
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    • 2010
  • As an observation instrument of the longest record of tropospheric water vapor, radiosonde data provide upper-air pressure (geopotential height), temperature, humidity and wind. However, the data have some well-known elements related to inaccuracy. In this article, radiosonde precipitable water vapor (PWV) at Sokcho observatory was compared with global positioning system (GPS) PWV during each summertime of year 2007 and 2008 and the biases were calculated. As a result, the mean bias showed negative values regardless of the rainfall occurrence. In addition, on the basis of GPS PWV, the maximum root mean square error (RMSE) was 5.67 mm over the radiosonde PWV.

The Development and Characteristics Analysis of High Precision Monitoring Sensor for the Marine Installation (해양설비용 정밀 모니터링 센서의 개발 및 특성 분석)

  • Cho, Jeong-Hwan;Ko, Sung-Won
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.10
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    • pp.101-106
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    • 2013
  • This paper proposes the new high precision monitoring sensor for the Marine Installation. Among variety of sensor network systems, wireless information transmission through the marine is one of the enabling technologies for the development of future marine-observation systems and sensor networks. Applications of marine monitoring range from oil industry to aquaculture, and include instrument monitoring, pollution control, climate recording, prediction of natural disturbances. For these marine applications to be available, however, the provision of precise location information using monitoring sensor is essential. In this paper, the dynamic characteristics for obtaining the location information of monitoring sensor is analyzed. The theoretical and experimental studies have been carried out. The presented results from the above investigation show considerably excellent performance for the Monitoring for the Marine Installation.

A Development of Exploration System for High Quality Underwater Mineral Resources (고품위 해저 광물자원 탐사시스템 개발)

  • Kim, Young-Jin;Cho, Young-June
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.316-319
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    • 2009
  • Currently for exploring marine resources, After confirming the location of the resources by controlling search equipment and sensor module in research vessel, the method which collects sample of searched resources and analyzes the quality and a contents of the resources in research vessel is been applying. This search method is structure which analyzes an ingredient in ship and decides the quality of the resources. And real-time processing for an effective resources search is been demanding. Therefore in this paper, we have developed a resources identification algorithm that can display the type feature of resources by real-time 3D Graphic.

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