• 제목/요약/키워드: NCU

검색결과 24건 처리시간 0.024초

NCURO DATA RETRIEVAL ALGORITHM IN FORMOSAT-3 GPS RADIO OCCULTATION OBSERVATION OF GRAVITY WAVE ACTIVITY

  • Yeh, Wen-Hao;Chiu, Tsen-Chieh;Liou, Yuei-An;Yan, Shian-Kun;Huang, Cheng-Yung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.192-195
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    • 2008
  • Radio occultation (RO) has been used in the planetary science since Microlab-1 was launched in 1995. With the RO technique, the profiles of atmosphere and the global atmospheric data can be obtained. In 2006, Taiwan launched six low Earth orbit (LEO) satellites as the RO constellation mission, known as FORMOSAT-3. In order to retrieve the RO data from original data, a retrieval algorithm, NCURO, is developed. The input of NCURO algorithm is mainly the excess phase of GPS signal, and the output is the dry pressure and dry temperature. Using temperature profiles retrieved by NCURO algorithm, temperature perturbation and potential energy of gravity wave have been evaluated. In this paper, the retrieval algorithm and the global distribution of energy of gravity waves are described and demonstrated.

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Open Loop Technique in FORMOSAT-3/COSMIC mission

  • Yeh, Wen-Hao;Chiu, Tsen-Chieh;Liou, Yuei-An;Huang, Cheng-Yung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.394-396
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    • 2007
  • Radio occultation (RO) technique has been used in planetary science since 1960s. When signal goes through atmosphere, it is refracted due to the gradient of atmospheric refractivity. In 1995, the first low earth orbit (LEO) satellite, MicroLab-1, was launched to conduct RO mission. It receives the signal from global positioning system (GPS) satellites. After MicroLab-1, other RO missions, such as CHAMP, SAC-C, and GRACE, are executed in several years later. In 2006, Taiwan launched six LEO satellites for RO mission. The mission name is Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC). Under some abnormal situations, multipath and strong fluctuation in phase and amplitude of the signal appear in moist troposphere. Therefore, open loop (OL) technique has been applied to replace traditional phase lock loop (PLL) technique. In this paper, we will summarize the retrieval processing procedure and discuss the advantages and disadvantages of OL technique.

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초음파침지처리에 의한 목재방부제의 주입성 (Penetrating Performance of Wood-preservatives by Ultrasonic Steeping)

  • 이명재;이동흡;이현미;손동원
    • Journal of the Korean Wood Science and Technology
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    • 제33권3호통권131호
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    • pp.64-71
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    • 2005
  • 본 실험에서는 초음파의 특성을 이용하여 목재를 방부처리하고 그 주입효과에 대해 검토하고자 하였다. 유용성 방부제인 NCU (나프텐산 구리)와 수용성 방부제 AAC (알킬암모늄 화합물)에 소나무 및 잣나무 시편을 침지한 후 40 kHz, 400 W 출력의 초음파를 발진시켰다. 초음파처리 이후 시편의 흡수율 및 침윤도는 시간 경과에 따라 지속적으로 증가하여 120시간 경과 후 AAC처리 잣나무, 소나무 모두에 대해 약 95%의 흡수율을 얻을 수 있었으며, 소나무 및 잣나무 각 시편 두께의 95, 83%에 해당하는 NCU의 침윤도를 얻을 수 있었다. 초음파 처리후의 시편을 SEM을 이용해 관찰하였으며, 초음파 발생에 의해 생성된 고온, 고압의 충격파가 목재 내 약액의 주입통로가 되는 벽공구를 파괴하고 초음파의 탈포작용과 목재내 추출물의 배출 등에 기인하여 약액의 주입성능이 향상된 것으로 판단된다. 초음파 처리에 의한 방부제의 주입은 가압방부처리의 적용이 어려운 소재, 단판 등에 적용이 가능할 것으로 판단된다.

The Construction and Application of Effective Coefficient for Aerosol Size Distribution

  • Lin, Tang-Huang;Liu, Gin-Rong;Chen, A.J.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.594-596
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    • 2003
  • Due to the fact that the composition and variability of aerosols is considered rather complex, it is difficult to employ a simple and straightforward physical model in calculating the aerosol size distribution in the absence of actual data. This complicates the already difficult retrieval of various atmospheric parameters from remotely sensed data. Thus, the main purpose of this study is trying to find an effective aerosol size coefficient that is stable, and can depict the particle size distribution. This paper also attempts to construct an 'effective aerosol size coefficient' database for each respective season, where it can quickly and effectively supply pertinent information of the atmosphere's opacity.

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A Study on the Retrieval Algorithms for Atmospheric Parameters from FORMOSAT-3/COSMIC Occultation Data

  • Yeh, Wen-Hao;Chiu, Tsen-Chieh;Huang, Cheng-Yung;Liou, Yuei-An
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.312-315
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    • 2006
  • Radio occultation technique has been used in planetary science to obtain reliable and accurate temperature profiles of the other planets' atmosphere for decades. It relies on the fact that radio waves are bent and delayed due to the gradient of atmospheric refractivity along-ray-path. With the advent of Global Positioning System (GPS), it becomes possible to retrieve the refractivity and temperature profiles of the Earth's atmosphere from the occultation data. We have developed a retrieval algorithm and compared the results of our algorithm with the data of CHAMP to verify the accuracy of our algorithm is good enough. In our algorithm, there are some smoothing steps when retrieving. We analysis the data of FORMOSAT-3 and compare the results with and without smoothing and the results of TACC to see is there any phenomenon deleted after smoothing.

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Effects of Sensoriomotor Functions on the Ipsilateral Upper Limb According to Cane Usage in Stroke Patients: A Preliminary Study

  • Son, Sung-Min;Kwon, Jung-Won;Kim, Chung-Sun
    • The Journal of Korean Physical Therapy
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    • 제23권3호
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    • pp.7-12
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    • 2011
  • Purpose: The cane is one of the most popular assistive devices for stroke patients. Clinical complaints of sensorimotor functions on the ipsilateral upper limb were appealed in stroke patients who had used a cane for a long period. Therefore, we investigated whether cane usage for a long-term period affected sensoriomotor dysfunctions on the non-affected upper limb, in terms of pain presence, shoulder joint sense, a nine-hole pegboard test, and a tracking task. Methods: We recruited 12 stroke patients, who were divided into the cane-using (CU) group or the non-cane using (NCU) group, according to cane usage experience. We evaluated joint position sense for the integrity of proprioceptive reposition sense in the shoulder joint, used a nine-hole pegboard test for upper limb dexterity evaluation, and a tracking task for visuomotor coordination. Results: Four patients in the CU group had complained of shoulder pain none did in the NCU group. In addition, the CU group showed more reposition errors on the shoulder joint than the NCU group did. In addition, the CU group had more difficulty in proprioceptive sense perception and in performance of the nine-hole pegboard teat and tracking task, compared with the NCU group. Conclusion: Our findings suggest that cane usage for a long period in stroke patients could give rise to trigger joint pain and decrease proprioceptive sense. In addition, complex motor performance in the ipsilateral upper limb could deteriorate. In stroke patients who had used acane for long period, careful observation and proper intervention will be necessary.

Data Quality Determination of Radio Occultation in moist troposphere

  • Yeh, Wen-Hao;Chiu, Tsen-Chieh;Liou, Yuei-An;Huang, Cheng-Yung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.442-444
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    • 2007
  • How to observe the atmosphere is a subject of atmospheric research. The meteorological satellites and the ground states are used to do observation. However, both ways do not satisfy the requirement of scientists, especially the profiles of atmosphere on the ocean and the data for global atmosphere. Radio occultation (RO) technique, which has been used in planet science, is a method to solve the problem. In RO technique, the low Earth orbit (LEO) satellite receives the two frequency signal of Global Positioning System (GPS) satellite. The excess phase of the signal is calculated to retrieve the profiles of atmosphere parameters. In moist troposphere, the fluctuations appear in the phase of the signal and open loop (OL) is used to resolve it. The quality of the GPS signal generally deteriorates as the altitude decreases. In the procedure, the SNR of the GPS signal is used as the criterion. However, the SNR decreases with fluctuation which makes it difficult to locate the data of poor quality. In this paper, the phase of the signal will be used as part of the criterion.

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일개 대학병원 신경외과중환자실에서 Clostridium difficile 관련 설사 감소를 위한 CQI활동 (CQI Activities for the Reduction of Clostridium difficile Associated Diarrhea in NCU of a University Hospital)

  • 박은숙;장경희;윤영옥;이정신;김태곤;여한승;김선호;신정원;이경원;김준명
    • 한국의료질향상학회지
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    • 제8권1호
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    • pp.10-21
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    • 2001
  • Background : The Clostridium difficile is the most important identifiable cause of nosocomial infectious diarrhea and colitis, which lengthens hospital stay. Recently incidence of C. difficile has been increasing in an university hospital, and an intervention for prevention and control of C. difficile associated diarrhea (CDAD) was in prompt need. Methods : Subjects were the patients in the neurosurgical intensive care unit(NCU) where C. difficile was most frequently isolated. To increase participation of various departments, we used the CQI method, because management of CDAD requires a wholistic approach including control of antibiotics, barrier precaution and environmental cleaning and disinfection. Duration of the CQI activities was 9 months from April to December 1999. Results : The identified problems were misuse and overuse of antibiotics, lack of consciousness of medical personnels and the possibility of transmission from the contaminated environment and tube feeding. Education for proper use of antibiotics and management of C. difficile infection, use of precaution stickers, supplement of handwashing equipments, emphasis on environmental disinfection, and the change of the process of tube feeding were done. The CDAD rate in NCU was significantly decreased after the CQI program (8.6 case per 1,000 patient days from January to April 1999 vs 4.8 from May to December 1999). The distribution of neurosurgical wards including NCU among the total number of isolated C. difficile from the clinical specimens dropped from 49.4% in January to April to 33,7% in May to December. The average hospital stay of the neurosurgical department changed from 19.6 days to 15.2 days. Also, the effect of the CQI activities for C. difficile may have affected the incidence of vancomycin resistant enterococci (VRE). Duration and dosage of certain antibiotics used in the NS department were decreased. The distribution of neurosurgical department in the number of VRE isolated patients declined from 18.4% to 11.1%. Conclusion : Infection control of resistant organisms such as C. difficile is likely to be successful when management of environmental contamination an collaborative efforts of decreasing the patients' risk factors such as antibiotics management and decreasing the length of hospital stay come simultaneously. For this work, related departments need to actively participate in the entire process under a common target through discussions for identifying problems and bringing up solutions. In this respect, making use of a CQI team is an efficient method of infection control for gathering participation and cooperation of related departments.

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Dust Properties in Afterglow of GRB071025 at z~5: Evidence for Supernovae-produced Dust in the Early Universe

  • Jang, Min-Sung;Im, Myung-Shin;Lee, In-Duk;Urata, Y.;Huang, L.;Fan, Xiaohui;Jiang, Lihua
    • 천문학회보
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    • 제35권2호
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    • pp.35.2-35.2
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    • 2010
  • It is crucial to understand the dust properties in the early universe since they provide important clues about how the early cosmic star formation should be interpreted in the presence of dust extinction. GRB 071025 is an unusually red GRB that occured at high redshift, offering an unique opportunity to study the dust properties in the early universe. We investigate the extinction properties of GRB 071025 through the analysis of RIJHK data obtained with the 1-m telescope at Mt. Lemmon Optical Astronomy Observatory (LOAO) and Simultaneous Quad Infrared Imaging Device (SQIID) on the Kitt-Peak Mayall 4-m telescope. Our dataset is independent from that in a previous work (Perley et al. 2010) where a small systematic photometric errors could complicate the interpretation. After determining the temporal power law exponent with five I-band frames from LOAO, we construct a multi-band monochromatic SED of the GRB afterglow. By using various extinction laws, we find that the SED is best fitted with models that incorporate SNe II dust and derive a photometric redshift of 4.99(+0.12/-0.03). Our results strongly support the prior claim that dusts in GRB 071025 originate mainly from supernovae, implying SNe II predominantly contributed to the dust enrichment in the early universe (z ~ 5).

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