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한반도의 일사량 추정을 위한 청천일 모델의 비교 평가 (Evaluation of Clear Sky Models to Estimate Solar Radiation over the Korean Peninsula)

  • 송아람;최원석;윤창열;김용일
    • 한국측량학회지
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    • 제33권5호
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    • pp.415-426
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    • 2015
  • 구름의 영향 없이 지표면에 도달하는 일사량을 추정하는 것은 일사량 자원지도의 궁극적인 목표이며, 이는 청천일 모델(clear sky model)을 사용하여 이론적으로 추정할 수 있다. 일사량 지도의 정확도는 청천일 모델의 정확도와 연결되기 때문에 연구목적과 연구지역에 적합한 청천일 모델을 선정하고 분석하는 것은 매우 중요하다. 본 연구에서는 대기혼탁 인자를 사용하여 일사량을 추정하는 고차원 모델(ESRA, Dumortier, MODTRAN)과 태양고도를 변수를 하는 일차원 모델(Bourges, PdBV)을 사용하여 한반도의 청천일 일사량을 추정하였으며, 실제 측정 자료와 비교하여 한반도에 적합한 청천일 모델을 분석하고자 하였다. 천리안 기상위성의 가시영상을 사용하여 구름이 없는 청명일을 참조자료로 추출하였으며, RMSE와 MBE를 계산하여 모델별 오차를 분석하였다. 연구결과, Bourges와 PdBV 모델이 실측치와 가장 낮은 RMSE를 가졌으며, PdBV는 계절에 상관없이 비교적 일정한 MBE값을 가졌다. 또한 봄-초여름 기간에 일차원모델은 일사량을 과소 추정하는 경향을 보였으며, 고차원모델은 겨울에 일사량을 과대 추정하는 것으로 나타났다. 추후 모델별로 나타난 오차의 경향 및 계절에 따른 오차를 보정하는 추가 연구를 통하여, 한반도에 최적화된 청천일 일사량 모델을 수정 및 개발할 예정이다.

안질환세균에 대한 도꼬마리 추출물의 항균 활성 (Antibacterial Activity of Xanthium strumarium L. Extract Against Bacteria Causing Eye Disease)

  • 한선희;김봉환
    • 한국안광학회지
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    • 제13권2호
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    • pp.69-73
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    • 2008
  • 목적: 이 논문은 안질환세균에 대한 도꼬마리 추출물의 항균활성을 알아보아 콘택트렌즈 관리용액에 첨가되어 있는 합성보존제를 대체할 천연 보존제로서의 가능성을 제시하기 위함이다. 방법: 안질환세균에 대한 도꼬마리 추출물의 항균활성은 한천 확산법(agar diffusion test)으로 측정했으며, 항균활성은 종이원반(paper disc) 주위의 선명지대(clear zone)의 생성유무와 선명지대(clear zone)의 크기(mm)로서 알아보았다. 실험에 사용한 세균은 포도상구균 (Staphylococcus)과 녹농균(Pseudomonas)이었다. 결과: Staphylococcus aureus KCCM 40050에 대한 도꼬마리 추출 물 $1000{\mu}g/20{\mu}l$농도의 선명지대는 11.5 mm로 나타났다. 또한 Pseudomonas aeruginosa KCCM 11803 균주에 대한 도꼬마리 추출물 $1000{\mu}g/20{\mu}l$농도의 선명지대는 9.0 mm, Pseudomonas fluorescens KCCM 40223 균주에 대해서는 7.0 mm로 나타났다. 결론: 이 실험을 통해 안질환세균에 대한 도꼬마리 추출물의 항균활성이 입증되었다. 따라서 도꼬마리 추출물이 콘택트렌즈 관리용액에 첨가될 천연 보존제로서의 가치가 충분히 있다고 판단되어진다.

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투명세포육종의 세침흡인 세포학적 소견 - 1예 보고 - (Fine Needle Aspiration Cytology of Clear Cell Sarcoma - A Case Report -)

  • 임성철;정유경;김동출;이윤경;신은택
    • 대한세포병리학회지
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    • 제9권2호
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    • pp.233-239
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    • 1998
  • Clear ceil sarcoma(CCS) is an uncommon soft tissue sarcoma that occurs in tendons and aponeuroses, usually of the lower extremities and is believed to be of neural crest origin that have a capability to produce melanin. These tumors commonly metastasize and have a very poor prognosis. The fine needle aspiration cytologic finding of CCS is not well documented. We recently experienced a case of CCS. The patient was a 54-year-old male with painful swelling of the right inguinal area. Fine needle aspiration cytology revealed polygonal or fusiform tumor cells with clear or granular cytoplasm and vesicular nuclei containing one or two nucleoli. Immunohistochemical staining for S-100 protein and HMB-45 revealed strong positivity and variable developing stages of premelanosomes were observed by electron microscopy in the excised specimen.

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서울시의 1993년 가을철 시정 및 입자 특성 측정 및 분석 (Measurement and Analysis of Visibility and the Characteristics of Particles during the Fall, 1993 in Seoul)

  • 백남준;김태오;김성주;김용표;문길주
    • 한국대기환경학회지
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    • 제10권1호
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    • pp.32-40
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    • 1994
  • Continuous measurements of the extinction coefficient( $b_{ext}$ ) and scattering coefficient due to Particle( $b_{sp}$ ) were made during the fall 1993 in Seoul along with the measurements of the size distribution, ionic composition of particles. On the average, $b_{sp}$ values are 55% and 79% of $b_{ext}$ values during the clear and smoggy Periods respectively. Also the average values of $b_{ext}$ and $b_{sp}$ were 0.791$\times$10$^{-3}$ $m^{-1}$ (visual range 4.9km) and 0.628$\times$10$^{-3}$ $m^{-1}$ (visual range 6.2km) during the smoggy Period, and 0.297$\times$10$^{-3}$ $m^{-1}$ (visual range 13.1km) and 0.164$\times$10$^{-3}$ $m^{-1}$ (visual range 23.8km) during the clear period, respectively. The Peak at about 1${\mu}{\textrm}{m}$ of the Particle size distribution during the smoggy period is about four times higher than that during the clear period while the peaks at about 5${\mu}{\textrm}{m}$ during both periods are similar. Also, the concentrations of sulfate and nitrate at about 1${\mu}{\textrm}{m}$ during the smoggy Period are much higher than these during the clear Period.eriod.

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사상체질별 음향특성(音響特性)과 신체질량지수(BMI)에 관(關)한 연구(硏究) (A Study on the sound characteristic and B.M.I by Sasang Constitution)

  • 김달래
    • 사상체질의학회지
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    • 제16권1호
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    • pp.53-60
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    • 2004
  • Purpose This study is to find the characteristics of voice quality based on the classifying the sound characteristics and B.M.I. by Sasang Constitution. Methods To make the notion of the consensus of Sasang Constitution's Voice, classification into 4 categories was made: clear/hoarse, high/low, powerful/powerless, fast/slow. Result The voice quality of Soyangin group was classified as powerful and fast, and that of Taeumin group was classified as powerful and hoarse and low, and that of Soeumin group was classified as powerless and clear. The mean B.M.I. of Soeumin group was classified as 21.4, and that of Taeumin group was classified as 26.3. Conclusion 1. Taeumin was significantly high compared with Soeumin in B.M.I. 2. It can be classified as Taeumin when B.M.I. is high(26.3). 3. It can be classified as Soeumin when B.M.I. is low(21.4). 4. The voice quality of Soyangin group was classified as clear and fast, or strong and clear, and that of Taeumin group as powerful and hoarse, and that of Soeumin group as powerless and low.

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경도 마비말장애 환자의 발화 유형에 따른 모음 특성 비교 (The change of vowel characteristics for the dysarthric speech along with speaking style)

  • 김지연;성철재
    • 말소리와 음성과학
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    • 제8권3호
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    • pp.51-59
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    • 2016
  • The purpose of present study is to examine differences between habitual speech (HS) and clear speech (CS) in individuals with mild dysarthria. Twelve speakers with mild dysarthria and twelve healthy control speakers read sentences in two speaking styles. Formant and intensity related values, triangular area, and center of gravity of /a/, /i/, and /u/ were measured. In addition, formant-ratio variables such as vowel space area(VSA), vowel articulatory index (VAI), formant centralization ratio (FCR) and F2i/F1u ratio (F2 ratio) were calculated. The results of repeated-measures ANOVA showed a significant difference in F2 of vowel /i/ and F2 energy of vowel /a/ between groups. Regarding formant energy, F2 energy of vowel /a/ were observed as meaningful variables between speaking styles. There were significant speaking style-by-group interactions for F2 energy of vowel /a/. These findings indicated that current parameters could discriminate healthy group and mild dysarthria group meaningfully and that speaker with dysarthria had larger clear speech benefit than healthy talkers. We also claim that various acoustic changes of clear speech may contribute to improving vowel intelligibility.

대학생들이 또렷한 음성과 대화체로 발화한 영어문단의 구글음성인식 (Google speech recognition of an English paragraph produced by college students in clear or casual speech styles)

  • 양병곤
    • 말소리와 음성과학
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    • 제9권4호
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    • pp.43-50
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    • 2017
  • These days voice models of speech recognition software are sophisticated enough to process the natural speech of people without any previous training. However, not much research has reported on the use of speech recognition tools in the field of pronunciation education. This paper examined Google speech recognition of a short English paragraph produced by Korean college students in clear and casual speech styles in order to diagnose and resolve students' pronunciation problems. Thirty three Korean college students participated in the recording of the English paragraph. The Google soundwriter was employed to collect data on the word recognition rates of the paragraph. Results showed that the total word recognition rate was 73% with a standard deviation of 11.5%. The word recognition rate of clear speech was around 77.3% while that of casual speech amounted to 68.7%. The reasons for the low recognition rate of casual speech were attributed to both individual pronunciation errors and the software itself as shown in its fricative recognition. Various distributions of unrecognized words were observed depending on each participant and proficiency groups. From the results, the author concludes that the speech recognition software is useful to diagnose each individual or group's pronunciation problems. Further studies on progressive improvements of learners' erroneous pronunciations would be desirable.

Introduction to Simulation Activity for CMDPS Evaluation Using Radiative Transfer Model

  • Shin, In-Chul;Chung, Chu-Yong;Ahn, Myoung-Hwan;Ou, Mi-Lim
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.282-285
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    • 2007
  • Satellite observed brightness temperature simulation using a radiative transfer model (here after, RTM) is useful for various fields, for example sensor design and channel selection by using theoretically calculated radiance data, development of satellite data processing algorithm and algorithm parameter determination before launch. This study is focused on elaborating the simulation procedure, and analyzing of difference between observed and modelled clear sky brightness temperatures. For the CMDPS (COMS Meteorological Data Processing System) development, the simulated clear sky brightness temperatures are used to determine whether the corresponding pixels are cloud-contaminated in cloud mask algorithm as a reference data. Also it provides important information for calibrating satellite observed radiances. Meanwhile, simulated brightness temperatures of COMS channels plan to be used for assessing the CMDPS performance test. For these applications, the RTM requires fast calculation and high accuracy. The simulated clear sky brightness temperatures are compared with those of MTSAT-1R observation to assess the model performance and the quality of the observation. The results show that there is good agreement in the ocean mostly, while in the land disagreement is partially found due to surface characteristics such as land surface temperature, surface vegetation, terrain effect, and so on.

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