• 제목/요약/키워드: SAR analysis

Search Result 437, Processing Time 0.031 seconds

Substituent Effect on the Fungicidal Activity of New N-substituted Benzotriazol-1-yl Derivatives (새로운 N-치환 benzotriazol-1-yl유도체의 항균활성에 미치는 치환기 효과)

  • Yu, Seong-Jae;Sung, Min-Gyu;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
    • /
    • v.40 no.1
    • /
    • pp.80-84
    • /
    • 1997
  • Series of new chiral N-substituted benzotriazol-1-yl derivatives were synthesized and their fungicidal activities in vitro against gray mold(Botrytis cinerea), black spot(Alternaria kikuchiana) and phytophthora blight(Phytophthora capsici) were measured by the agar medium dilution method. The substituents effects between the fungicidal activities (obs. $pI_{50}$) and a various physicochemical parameters of phenoxy or thiophenoxy group(X) & alkyl or phenyl group(Y) were analyzed by the multiple regression technique. From the analyzed substituent effects, the structure-activity relationship(SAR) equations shows that the antifungal activities depend on the parameters for the optimal molecular hydrophobicity($({\Sigma}logP)_{opt}$), Van der Waals (${\Sigma}Vw$>0) volume(${\AA}^3$) and inductive constant with electron withdrawing group(${\sigma}_I$,Y>0). The activity in affected by the inductive effect (${\sigma}_I$,Y>${\sigma}_g$X) of Y-group rather than the X-group. The phenoxy substituents, 1, showed higher antifungal activity tn the thiophenoxy substituents, 2. For 1, polar substituent constant(${\sigma}^*$) was an important factor in determining the activity. And the tribromomethyl substituent, 1g showed the highest activity against the tee fungi.

  • PDF

Technical Status of Microwave Remote Sensing of Tropical Cyclones (열대저기압 마이크로파 원격탐사의 기술 현황)

  • Choi, Geun-Chul;Yang, Chan-Su;Pack, Han-Il
    • Proceedings of KOSOMES biannual meeting
    • /
    • 2006.11a
    • /
    • pp.193-199
    • /
    • 2006
  • This article reviews several microwave instruments employed in observation and analysis of tropical cyclones (TCs), typhoon, and hurricanes. Microwave signals are useful for observing tropical cyclones with severe storms since it isn't severely absorbed by the clouds and rain in the storm. The instruments discussed include scatterometers, microwave radiometers, synthetic aperture radars (SARs), and rain radar from space. The date such as winds, rainfall and cloud-distribution in the TCs obtained by microwave instruments provide important informations for forecasting the intensity and path of the typhoon. For example, there're wind-distribution provided by SSM/I which has a wide swath, detailed wind fields from ERS-1, 2 scatterometers and RADARSAT-1 SAR and TRMM's rain radar pro 떠 ding high resolution. Operational satellite instruments lunched recently have improved upon the problems of low resolution and narrow swath indicated at the beginning microwave remote sensing. Understanding and practical using sufficiently about the microwave instruments will serve for searching the features such as generation and development of the TCs.

  • PDF

Analysis of Backscattering Coefficients of Corn Fields Using the First-Order Vector Radiative Transfer Technique (1차 Vector Radiative Transfer 기법을 이용한 옥수수 생육에 따른 후방산란 특성 분석)

  • Kweon, Soon-Koo;Hwang, Ji-Hwan;Park, Sin-Myeong;Hong, Sungwook;Oh, Yisok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.25 no.4
    • /
    • pp.476-482
    • /
    • 2014
  • In this study, we analyzed the effect of corn growth on the radar backscattering coefficient. At first, we measured the backscattering coefficients of various corn fields using a polarimetric scatterometer system. The backscattering coefficients of the corn fields were also computed using the 1st-order VRT(Vector Radiative Transfer) model with field-measured input parameters. Then, we analyzed the experimental and numerical backscattering coefficients of corn fields. As a result, we found that the backscatter from an underlying soil layer is dominant for early growing stage. On the other hand, for vegetative stage with a higher LAI(Leaf-Area-Index), the backscatter from vegetation canopy becomes dominant, and its backscattering coefficients increase as incidence angle increases because of the effect of leaf angle distribution. It was also found that the estimated backscattering coefficients agree quite well with the field-measured radar backscattering coefficients with an RMSE(Root Mean Square Error) of 1.32 dB for VV-polarization and 0.99 dB for HH-polarization. Finally, we compared the backscattering characteristics of vegetation and soil layers with various LAI values.

The Effects of the Balance Training Program on the Excercise Performance and Injuries (정적균형훈련이 운동수행력 및 상해발생에 미치는 영향(탄성을 이용한))

  • Park, Sung-Hark
    • Journal of Korean Physical Therapy Science
    • /
    • v.11 no.3
    • /
    • pp.14-27
    • /
    • 2004
  • This study approaches the effects of Balance Training on excercise performance and the prevention from the injuries caused by excercise. The subjects of the Balance Training program are female exercise beginners and the research period covers 8 weeks from January 10 to March 7, 2003. The research objects are 19 female golf beginners in 30s to 40s, who live in Seoul or Seongnam in Gyeonggi province and have played golf less than 6 months. The programs of the Balance Training and exercise performance were conducted to an 11 experimental group among the 19 research objects at the same time, and only the exercise performance program was applied to an 8 control group for 8 weeks. Before and after 8 weeks' application of the research programs to each group, the research subjects were examined, especially the components of their bodies, the balance and the performance capability were measured both before and after the test. The frequency of injuries by exercise was measured after the test, and the difference of the frequency was compared with the frequency before exercise. First, the experimental group, in a measurement of balance, showed that SN, MB, SAr and SAg of static balance decreased in a situation of MEO, MEC, GEO, GEC, TBEO, TBO, FHEO, FEO(p <0.05), but the control group increased. Second, the analysis on the change of exercise performance indicated better improvement in distance, ball speed, and accuracy of the experimental group than the control group(p<0.05). Third, the experience of injuries showed that there were 2 injuries in the experimental group and 11 injuries in the control group. The injured parts were 2 cases in the hands and fingers of the experimental group, and 1 case in the shoulder, 4 in the elbows, 4 in the hands and fingers and 2 in the lumber of the control group. From the above-mentioned results, it is recognized that the Balance Training program improved the exercise performance of female golf beginners and had good effects on the prevention from injuries. Accordingly, if this program is applied to sports-beginners, it will contribute to the improvement of the public health.

  • PDF

A Comparative Study on the Goodness of Fit in Spatial Econometric Models Using Housing Transaction Prices of Busan, Korea (부산시 실거래 주택매매 가격을 이용한 공간계량모형의 적합도 비교연구)

  • Chung, Kyoun-Sup;Kim, Sung-Woo;Lee, Yang-Won
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.15 no.1
    • /
    • pp.43-51
    • /
    • 2012
  • The OLS(ordinary least squares) method is widely used in hedonic housing models. One of the assumptions of the OLS is an independent and uniform distribution of the disturbance term. This assumption can be violated when the spatial autocorrelation exists, which in turn leads to undesirable estimate results. An alterative to this, spatial econometric models have been introduced in housing price studies. This paper describes the comparisons between OLS and spatial econometric models using housing transaction prices of Busan, Korea. Owing to the approaches reflecting spatial autocorrelation, the spatial econometric models showed some superiority to the traditional OLS in terms of log likelihood and sigma square(${\sigma}^2$). Among the spatial models, the SAR(Spatial Autoregressive Models) seemed more appropriate than the SAC(General Spatial Models) and the SEM(Spatial Errors Models) for Busan housing markets. We can make sure the spatial effects on housing prices, and the reconstruction plans have strong impacts on the transaction prices. Selecting a suitable spatial model will play an important role in the housing policy of the government.

Embodiment of High Impedance Surface of Meta-Material Characteristic Using Symmetrical AMC Structure and Its SAR Analysis (대칭형 인공자기도체 구조를 이용한 메타물질 특성의 고임피던스 표면 구현 및 SAR 특성 분석)

  • Lee, Seungwoo;Lee, Moung-Hee;Rhee, Seung-Yeop;Kim, Nam
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.38B no.9
    • /
    • pp.744-750
    • /
    • 2013
  • In this paper, we proposed new type of an artificial magnetic conductor(AMC) structure, which has a high impedance surface for realizing the meta-material characteristics. The designed AMC structure set a goal of 3.2GHz, and the reflector, which consists of periodically arrayed AMCs is fabricated and measured. The high impedance improves the reflection coefficient, decreases the system size and interference, and increases the antenna performance. The structure has embodied the high impedance by the thickness and relative permitivity of the dielectric substrate and the design configuration without the metallic via hole which connects the AMC to the GND. The bandwidth is 150% broader than the similar AMC structures. Also, the distance between the antenna and the AMC reflector is decreased by ${\lambda}/10$ as working as the metal(PEC) reflectors. The antenna radiation characteristics are 3dB increased at 10mm away from reflector by measurement. The proposed reflector could be inserted in the portable mobile devices, and the antenna's performance has improved by the reflector. The specific absorption rate is dramatically decreased over 94% because the back radiation of the antenna is shielded.

A Study on Water Surface Detection Algorithm using Sentinel-1 Satellite Imagery (Sentinel-1 위성영상을 이용한 수표면 면적 추정 알고리즘에 관한 연구)

  • Lee, Dalgeun;Cheon, Eun Ji;Yun, Hyewon;Lee, Mi Hee
    • Korean Journal of Remote Sensing
    • /
    • v.35 no.5_2
    • /
    • pp.809-818
    • /
    • 2019
  • The Republic of Korea is very vulnerable to damage from storm and flood due to the rainfall phenomenon in summer and the topography of the narrow peninsula. The damage is recently getting worse because of the concentration rainfall. The accurate damage information production and analysis is required to prepare for future disaster. In this study, we analyzed the water surface area changes of Byeokjeong, Sajeom, Subu and Boryeong using Sentinel-1 satellite imagery. The surface area of the Sentinel-1 satellite, taken from May 2015 to August 2019, was preprocessed using RTC and image binarization using Otsu. The water surface area of reservoir was compared with the storage capacity from WAMIS and RIMS. As a result, Subu and Boryeong showed strong correlations of 0.850 and 0.941, respectively, and Byeokjeong and Sajeom showed the normal correlation of 0.651 and 0.657. Thus, SAR satellite imagery can be used to objective data as disaster management.

A Review on Remote Sensing Techniques and Case Studies for Active Fault Investigation (활성단층 조사에 활용되는 원격탐사 기술과 사례의 고찰)

  • Gwon, Ohsang;Son, Hyorok;Bae, Sangyeol;Park, Kiwoong;Choi, Ho-Seok;Kim, Young-Seog;Lee, Seoung-Kuk
    • Korean Journal of Remote Sensing
    • /
    • v.37 no.6_2
    • /
    • pp.1901-1922
    • /
    • 2021
  • Since most large earthquakes occur by reactivation of preexisting active faults, it is important to understand the locations and characteristics of active faults in terms of earthquake hazard research and earthquake disaster prevention. Recently, several remote sensing techniques are broadly used for lineament analysis performed prior to field surveys in active fault surveys. The aim of this paper is introducing simple principles and application examples of each remote sensing technique (satellite remote sensing, airborne remote sensing, InSAR, LiDAR) widely used for active fault investigation. This paper also explains the analytical methods for the slope break generated by fault activity based on GIS and the horizontal displacement of the strike-slip fault. In discussion, we would like to discuss the problems and solutions on making DEM based on aerial photography, and a new developed technique (RRIM) to overcome the problems of DEM based on aerial LiDAR. Understanding remote sensing techniques used for active fault investigation and utilizing appropriate methods depending on the situation and limitations of each remote sensing technique are important for effective active fault investigation.

The Development of Earthenware Kilns in Bongsan-ri Archaeological Site, Osong: Implications for Pre- and Post-1950 AD Absolute Age Determination (AD 1950년 전후 고고유적의 절대연대측정에 대한 고찰: 오송 봉산리 옹기가마 유적을 중심으로)

  • Kim, Myung Jin;Son, Myoung Soo;Kim, Tae Hong;Sung, Ki Seok
    • Journal of Conservation Science
    • /
    • v.34 no.6
    • /
    • pp.481-492
    • /
    • 2018
  • We conducted TL/OSL dating for the earthenware kilns in the Bongsan-ri archaeological site, Osong, which was occupied from the late nineteenth to the late twentieth century. With the SAR-TL/OSL method, paleodose was determined from the equivalent dose during the burial period($ED_{burial}$), the background dose($ED_{BG}$), the fading correction factor(f), and the overestimation correction factor(C). The annual dose rates and their provenance were evaluated from the measurement of natural radionuclides $^{238}U$, $^{232}Th$, and $^{40}K$. Because the comprehensive absolute age was provided by combining the resulting TL/OSL and radiocarbon data, we concluded that, for the absolute chronology of a modern archaeological site, TL/OSL dating and radiocarbon dating must be carried out together and summed. The construction and occupation of earthenware kilns in the Bongsan-ri site had changed from stage I (No.5, 6 kilns), to stage II (No.1, 2, 3 kilns), to stage III (No.4) in chronological order. When Bayesian statistics were applied, we found that the absolute ages of occupation for stages I, II, and III correspond to AD $1910{\pm}23$, AD $1970{\pm}10$, and AD $1987{\pm}4$. These results were in good agreement with the archaeological context or chronology.

A Study of Development and Application of an Inland Water Body Training Dataset Using Sentinel-1 SAR Images in Korea (Sentinel-1 SAR 영상을 활용한 국내 내륙 수체 학습 데이터셋 구축 및 알고리즘 적용 연구)

  • Eu-Ru Lee;Hyung-Sup Jung
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.6_1
    • /
    • pp.1371-1388
    • /
    • 2023
  • Floods are becoming more severe and frequent due to global warming-induced climate change. Water disasters are rising in Korea due to severe rainfall and wet seasons. This makes preventive climate change measures and efficient water catastrophe responses crucial, and synthetic aperture radar satellite imagery can help. This research created 1,423 water body learning datasets for individual water body regions along the Han and Nakdong waterways to reflect domestic water body properties discovered by Sentinel-1 satellite radar imagery. We created a document with exact data annotation criteria for many situations. After the dataset was processed, U-Net, a deep learning model, analyzed water body detection results. The results from applying the learned model to water body locations not involved in the learning process were studied to validate soil water body monitoring on a national scale. The analysis showed that the created water body area detected water bodies accurately (F1-Score: 0.987, Intersection over Union [IoU]: 0.955). Other domestic water body regions not used for training and evaluation showed similar accuracy (F1-Score: 0.941, IoU: 0.89). Both outcomes showed that the computer accurately spotted water bodies in most areas, however tiny streams and gloomy areas had problems. This work should improve water resource change and disaster damage surveillance. Future studies will likely include more water body attribute datasets. Such databases could help manage and monitor water bodies nationwide and shed light on misclassified regions.