• 제목/요약/키워드: Brightness temperature

검색결과 450건 처리시간 0.031초

TeraScan시스템에서 NOAA/AVHRR 해수면온도 산출시 구름 영향에 따른 신뢰도 부여 기법: 5월 자료 적용 (Generation of Sea Surface Temperature Products Considering Cloud Effects Using NOAA/AVHRR Data in the TeraScan System: Case Study for May Data)

  • 양성수;양찬수;박광순
    • 한국해양환경ㆍ에너지학회지
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    • 제13권3호
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    • pp.165-173
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    • 2010
  • 본 연구에서는 TeraScan시스템에서 산출되는 NOAA/AVHRR 해수면온도(SST) 자료의 신뢰도를 부여하기 위한 방법으로 구름 영향 정도를 단계별로 나누는 방법을 소개한다. TeraScan시스템에서 구름탐지는 주간과 야간에 따라 다른 파라미터와 경계값을 사용한다. 주간 구름탐지에서는 채널 2번(가시채널)과 4번(적외채널)을 이용하며, 채널 4번 휘도온도의 공간일관성(ch4_delta)과 채널 2번 알베도의 공간일관성(ch2_delta) 및 알베도 경계값(ch2_max) 검사를 수행한다. 야간의 경우, 가시채널을 사용할 수 없기 때문에 채널 3번(단파적외채널)과 4번(적외채널)을 사용하여 각 화소에 대한 차이값(ch3_minus_ch4)을 비교하고, 채널 4번 휘도온도 공간일관성(ch4_delta) 및 경계값(min_ch4_temp) 평가가 이루어진다. 여기서는 주야에 따른 변화를 보기 위해 2009년 5월 13일 00시 48분(UTC)과 21시 00분(UTC) 에 수신된 자료를 사용했다. TeraScan시스템을 통해 총 6가지 경계치를 검토했고, ch4_delta는 우리나라 주변 수온 전선에서 발생하는 구름 탐지 오류가 발생하지 않는 값으로 주야간 각각 5와 3.5로 결정되었다. 주간 파라미터로 사용되는 ch2_delta는 여러 값에 대한 적용 결과 2로, ch2_max는 3부터 8까지의 범위가 적절한 것으로 나타났다. 야간에 사용되는 ch3_minus_ch4는 -2부터 2까지의 범위, min_ch4_temp는 0으로 결정되었다. 즉, 구름의 영향 정도는 주간 ch2_max와 야간 ch3_minus_ch4의 경계값을 4 단계로 나눠 해수면온도자료를 산출하였다. 본 연구에서 사용한 경계값은 5월 자료에 대해 설정된 값이며, 향후 한반도 주변 해역의 특성과 시간별, 공간별, 계절별로 적절한 경계값을 설정하는 연구가 장기적으로 필요하며, 위의 특성들을 감안한 자료동화용 SST 생산프로세스 정립 및 결과분석 연구가 필요하다.

수확시기와 저장방법에 따른 마의 塊根重과 품질변화 (Tuber Yield and Characteristics of Chinese Yam as Affected by Harvesting Date and Storage Condition)

  • 김영광
    • 한국자원식물학회지
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    • 제11권2호
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    • pp.136-141
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    • 1998
  • To give some information on the harvest and storage of Chinese yam (Dioscorea opposita), the experiment was done to examine the effect of its harvesting date and storage method on tuber weight, tuberrelated characters during the storageor at the end of storage. The yam tubers harvested 4 times at 20 days interval from Oct. 15 were stored with different storage methods(pit, room and cold temperature) and on Mar.15. all the characters were measured. Fresh weight of the tuber harvestedafter Nov. 5 and stored were greater than that done on Oct. 15 while dry tuber weight did not have any difference between the harvesting dates. The fresh weigth done directly from the field on Mar. 15 was higher compared to the other harvesting dates owing to its higher moisture content. The rate of sound tuber stored at room or cold temperature condition was higher than that at the field at which the rate was greater at the harvest after late nov. compared to the earlier harvests. Although the two storages were similar at sound tuber rates and marketable yield, the tuber weight was more reduced when stored at room temperature than when done at cold temperature . Brightness and value 'b' of chromaticaity realted to the tuber coloring and sugar content were higher but moisture content was lowerwhen harvested on Oct. 15 than the other havesting dates. All the characteristics realted to the marketability after storage were nearly same when stored at room and cold temperature. Value 'a' of chromaticity and sugar content were higher when harvest on Mar. 15 than when harvested before Dec. 15 but the 'b' value and mositure content were reverse results.

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실험계획법을 이용한 고지 해리 공정조건에 관한 연구 (A Study on Pulping Process Condition through Design of Experiments)

  • 김성권;이준구;성대형
    • 공업화학
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    • 제9권4호
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    • pp.529-535
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    • 1998
  • 탈묵공정에서 고지 배합처리, 온도, 양품 배합처리 등의 해리 공정조건 변동에 의한 탈묵펄프의 영향을 조사하였다. 실험계획법으로써 탈묵펄프에 주된 영향을 미치는 유의한 인자를 선정하였으며, 통계분석기법 중 하나인 분산분석 및 다중비교를 통해 공정조건의 최적수준조합을 결정하고 이에 따른 백색도 및 강도적 특성의 추정치 및 신뢰구간을 구하였다. 백색도는 $Na_2SiO_3$ 2.0%, $H_2O_2$ 0.5%, 고지 배합처리 (국내신문고지 : 수입신문고지 : 매거진 = 40 : 30 : 30 wt %)의 조건에서 가장 높은 추정치 50.5%와 90% 신뢰구간 (49.0, 52.0)을 얻을 수 있었다. 인장지수는 $H_2O_2$ 0.5%, 해리 온도 $50^{\circ}C$의 조건에서 가장 높은 추정치 $35.7N{\cdot}m/g$과 90% 신뢰구간 (34.6, 36.6)을 얻을 수 있었다. 파열지수는 계면활성제 0.1%, 해리 온도 $50^{\circ}C$의 조건에서 가장 높은 추정치 $0.129kPa{\cdot}m^2/g$과 90% 신뢰구간 (0.125, 0.133)을 얻을 수 있었다.

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앙각변동에 따른 Ku 밴드 안테나 G/T 분석 및 실험 (Ku Band Antenna G/T Analysis and Experiment According to Elevation Angle Change)

  • 이경순;구경헌
    • 한국전자파학회논문지
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    • 제28권7호
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    • pp.550-559
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    • 2017
  • 위성 단말기가 차량 이동하면서 통신을 유지하려면 실시간 안테나 방위각과 앙각 보정이 필요하다. 앙각 보정은 안테나에 유입되는 외부 잡음온도 변동을 수반하여 시스템 G/T에 영향을 끼친다. G/T는 안테나이득 G(Gain)와 잡음온도 T(Noise temperature)의 비율로 표현되며, 안테나 이득설계에 필요한 중요 성능지수이다. 본 논문은 앙각변동을 고려한 G/T 분석 및 안테나 설계절차 수립을 목표로 한다. 이를 위해 ITU-R P.372 Radio Noise 권고사항에 따라 강우감쇠를 포함한 휘도온도와 앙각과의 관계를 분석하였다. 다음에 분석결과를 기반으로 안테나를 제작하여 G/T 측정에 의한 설계절차를 검증하였다. 이 실험을 통해 앙각에 따른 G/T를 확인하였으며, 시스템에서 요구되는 최소 안테나 이득 분석 및 설계절차를 수립할 수 있었다.

Accuracy evaluation of near-surface air temperature from ERA-Interim reanalysis and satellite-based data according to elevation

  • Ryu, Jae-Hyun;Han, Kyung-Soo;Park, Eun-Bin
    • 대한원격탐사학회지
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    • 제29권6호
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    • pp.595-600
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    • 2013
  • In order to spatially interpolate the near-surface temperature (Ta) values, satellite and reanalysis methods were used from previous studies. Accuracy of reanalysis Ta was generally better than that of satellite-based Ta, but spatial resolution of reanalysis Ta was large to use at local scale studies. Our purpose is to evaluate accuracy of reanalysis Ta and satellite-based Ta according to elevation from April 2011 to March 2012 in Northeast Asia that includes various topographic features. In this study, we used reanalysis data that is ERA-Interim produced by European Centre for Medium-Range Weather Forecasts (ECMWF), and estimated satellite-based Ta using Digital Elevation Meter (DEM), Normalized Difference Vegetation Index (NDVI), difference between brightness temperature of $11{\mu}m$ and $12{\mu}m$, and Land Surface Temperature (LST) data. The DEM data was used as auxiliary data, and observed Ta at 470 meteorological stations was used in order to evaluate accuracy. We confirmed that the accuracy of satellite-based Ta was less accurate than that of ERA-Interim Ta for total data. Results of analyzing according to elevation that was divided nine cases, ERA-Interim Ta showed higher accurate than satellite-based Ta at the low elevation (less than 500 m). However, satellite-based Ta was more accurate than ERA-Interim Ta at the higher elevation from 500 to 3500 m. Also, the width of the upper and lower quartile appeared largely from 2500 to 3500 m. It is clear from these results that ERA-Interim Ta do not consider elevation because of large spatial resolution. Therefore, satellite-based Ta was more effective than ERA-Interim Ta in the regions that is range from 500 m to 3500 m, and satellite-based Ta was recommended at a region of above 2500 m.

Bleaching of Kraft Pulp with Lignin - Degrading Enzymes

  • Harazono, Koich;Kondo, Ryuichrto;Sakai, Kokki
    • 펄프종이기술
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    • 제29권2호
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    • pp.83-90
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    • 1997
  • An unbleached hardwood kraft pulp was bleached in vitro with partially purified manganese peroxidase (MnP) from the fungus Phanerochaete sordida YK-624 without the addition of MnSO$_4$ in the presence of oxalate, malonate or gluconate known as manganese chelator, When the pulp was treated without the addition of MnSO$_4$, the pulp brightness increased by about 10 points in the presence of 2 mM oxalate, but the brightness did not significantly increase in the presence of 50 mM malonate. Residual MnP activity decreased faster during the bleaching with MnP without MnSO$_4$ in the presence of malonate than in the presence of oxalate. Oxalate reduced MnO$_2$ which already existed in the pulp or was produced from $Mn^{2+}$ by oxidation with MnP and thus supplied $Mn^{2+}$ to the MnP system. Thus, bleaching of hardwood kraft pulp with MnP, using manganese originally existing in the pulp, became possible in the presence of oxalate, a good manganese chelator and reducing reagent. Properties of partially purified MnPs from liquid cultures of white rot fungi, Ganoderma sp. YK-505, Phanerochaete sordida YK-624 and Phanerochaete chrysosporium were compared. MnP from Ganoderma sp. YK-505 was superior to MnPs from P. sordida YK-624 and P. chrysosporium in stabilities against high temperature and high concentration of $H_2O$$_2$. The MnP from Ganoderma sp. YK-505 differed in pH-activity profile from other MnPs. These data suggest that MnP from Ganoderma sp. YK-505 has different structure from those of other fungi. Bleaching of hardwood kraft pulp using the MnP from ganoderma sp. YK-505 is now in progress.

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The Effect of Hydrogen Peroxide Bleaching on the Properties of Unbleached Hardwood Kraft Pulp Adsorbed with Birchwood Xylan

  • ;이상훈;이학래;윤혜정
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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    • pp.169-169
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    • 2011
  • Xylans are polysaccharides present in large amounts in cell walls of land plants. However, during kraft cooking, a high portion of hemicelluloses including xylans are dissolved in the cooking liquor. In the current trend for a more effective utilization of biomass, attention has been paid to the exploitation of xylans as strength-enhancing additives for paper. It is believed that surface xylan adds flexibility to the cell wall/fiber surface, resulting in stronger fiber-fiber joints or greater contact area between the fibers. Accordingly, there is proposal for a new pulping process involving the extraction of xylan prior to pulping, followed by their re-adsorption on the unbleached pulp. A suitable bleaching process should be employed then, which ought to does not only improve the brightness of the pulp, but also remain the effect of the adsorption of xylan on pulp fibers. The objective of this research was to investigate the impact of hydrogen peroxide bleaching on the properties of unbleached hardwood kraft pulp pretreated with birchwood xylan by measuring optical properties (brightness, post color number, opacity) as well as physical properties (tensile index, tearing index, bulk) of handsheets made from the bleached pulp. In the meantime, the influence of process variables of peroxide bleaching including bleaching temperature, time, initial pH and $MgSO_4$ dosage were studied.

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Organosolv 방법(方法)에 의(依)한 활엽수(闊葉樹) 주요(主要) 조성분(組成分)의 분리(分離) 및 이용(利用) (Separation and Utilization of Main Components of Hardwood by Organosolv Pupling)

  • 백기현;안병준;남원석
    • Journal of the Korean Wood Science and Technology
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    • 제16권4호
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    • pp.70-78
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    • 1988
  • To separate and utilize the main components of hardwood (Quercus mongolica) by organosov pulping (ester pulping), chips were cooked at various conditions such as; the solvent ratio (acetic acid: ethylacetate: water, 50:25:25; 33:33:34; 25:50:25), maximum temperature (165, 170, $175^{\circ}C$), and cooking times (2, 2.5, 3 hr). The pulps were bleached by the sequences of CEDED, C/DEDED, PEDED. Lignin, sugars, and acetic acid were separated from black liquor and washing liquors. 1. The selective delignification at optimal pulp yield (43-45%) was obtained by cooking at acetic acid: ethylace tate: water ratio of 33:34:34 for 3 hr at $170^{\circ}C$. But in this case, kappa no. of the pulp was not reduced under 60 points. 2. Kappa no. of the pulp could be dropped by an acetone wash to remove reprecipitated lignin a t cooked pulp. 3. The unbleached pulps had a brightness of 45-50%, whereas the bleached pulps gave at 88-93% brightness. Tensile, burst, and tear strengths of the bleached pulps were lower than those of kraft pulp, especially in tear strength. The pulps which were bleached with CEDED sequence were higher in strengths than another bleaching sequences. 4. Lignin of 90-95%(lignin base on wood)was separated from black liquor and washing liquors, while the purified sugars and recovery of acetic acid were a low. An organic phase composed of acetic acid, ethylacetate, and water was separated to a two-phase system by proper adjustment of the solvent ratios.

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A Study on Dyeing Properties and Color Research of Knitted Fabric and by Scoria

  • Chung, In-Hee
    • 패션비즈니스
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    • 제11권3호
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    • pp.79-86
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    • 2007
  • The purpose of this study is to understand the dyeing properties and color analysis of fabrics knitted with ramie, cotton, wool and acrylic by using scoria and to analyze whether the knitted fabrics can be used for industrialization by measuring color fastness after and before sliver-nano process. The following is the conclusions. Firstly, when ramie fabric regarding cotton, wool and acrylic was dyed at the temperature of $50^{\circ}C$ for fifteen minutes by using 10, 25, 50, 100g/ $\ell$ of scoria, dyeing absorption gradually increased up to 50g/ $\ell$, and over the point of 50g/ $\ell$ it showed slow increase. Secondly, regarding saturation, among ramie fabric, wool, cotton and acrylic, wool appears as the lowest brightness. Therefore, it can be dyed with bright color and the highest value. In terms of the value of chromaticity, wool also emerges as the lowest brightness. On the contrary, acrylic showed the lightest red as it had the value of the smallest b. Cotton takes the lightest yellow as the b value of the cotton showed the smallest. Thus, scoria dyestuff is a material that showed strong red and yellow on knitted fabric mixed with wool that is the biggest a. b value. Thirdly, in terms of dyeing fastness, sunlight fastness did not show noticeable differences before and after silver-nano processes, but in terms of washing and friction fastness, the material processed by silver-nano indicated that all knitted fabrics are over 4-5 point. which means silver-nano process can be effective for the industrial applications. As mentioned above, as a result of dyeing knitted fabrics with scoria, this study found a possibility of dyeing in the fabric materials, and if there is deeper dyeing experiments, fastness experiments and speculations, it might be possible to be a big issue just like loess and charcoal.

스마트안전 리빙랩에서의 스마트 조명 사용자경험 평가 (Evaluation of Smart Lighting User Experience in Smart Safety Living Lab)

  • 조은지;류도현;김광재;이기현;윤정민;조정현;전광식;이지연
    • 품질경영학회지
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    • 제50권4호
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    • pp.679-700
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    • 2022
  • Purpose: Smart lighting adjusts brightness and color temperature according to weather, the user's activity, mood, etc. This study performed user experience(UX) evaluation of smart lighting in a living lab. The purpose of evaluating UX and analyzing the evaluation results is to improve user-friendliness and market competitiveness of smart lighting Methods: A living lab is a virtual or physical space where various stakeholders participate to develop, verify, and evaluate products, services, or systems in a real-life environment. In this study, an environment of using smart lighting was established in the Smart Safety Living Lab. Subjects performed UX evaluation after interacting freely with smart lighting in the Smart Safety Living Lab. Results: As a result of UX evaluation, it was confirmed that UX was overall excellent and subjects were satisfied with setting a desired indoor mood through smart lighting. However, operating the switch of smart lighting may be difficult due to its complexity, and it is needed to improve some functionalities such as the brightness range provided by smart lighting. Conclusion: This study is expected to contribute to establishing the way of UX improvement of smart lighting. This study is also expected to contribute to developing smart lighting as a high-quality product by reflecting the subjects' needs and UX derived in a real-life environment.