• Title/Summary/Keyword: optimal band

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A Method of Feature Extraction on Motor Imagery EEG Using FLD and PCA Based on Sub-Band CSP (서브 밴드 CSP기반 FLD 및 PCA를 이용한 동작 상상 EEG 특징 추출 방법 연구)

  • Park, Sang-Hoon;Lee, Sang-Goog
    • Journal of KIISE
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    • v.42 no.12
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    • pp.1535-1543
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    • 2015
  • The brain-computer interface obtains a user's electroencephalogram as a replacement communication unit for the disabled such that the user is able to control machines by simply thinking instead of using hands or feet. In this paper, we propose a feature extraction method based on a non-selected filter by SBCSP to classify motor imagery EEG. First, we divide frequencies (4~40 Hz) into 4-Hz units and apply CSP to each Unit. Second, we obtain the FLD score vector by combining FLD results. Finally, the FLD score vector is projected onto the optimal plane for classification using PCA. We use BCI Competition III dataset IVa, and Extracted features are used as input for LS-SVM. The classification accuracy of the proposed method was evaluated using $10{\times}10$ fold cross-validation. For subjects 'aa', 'al', 'av', 'aw', and 'ay', results were $85.29{\pm}0.93%$, $95.43{\pm}0.57%$, $72.57{\pm}2.37%$, $91.82{\pm}1.38%$, and $93.50{\pm}0.69%$, respectively.

Analysis of Spectral Reflectance Characteristics Using Hyperspectral Sensor at Diverse Phenological Stages of Soybeans

  • Go, Seung-Hwan;Park, Jin-Ki;Park, Jong-Hwa
    • Korean Journal of Remote Sensing
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    • v.37 no.4
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    • pp.699-717
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    • 2021
  • South Korea is pushing for the advancement of crop production technology to achieve food self-sufficiency and meet the demand for safe food. A medium-sized satellite for agriculture is being launched in 2023 with the aim of collecting and providing information on agriculture, not only in Korea but also in neighboring countries. The satellite is to be equipped with various sensors, though reference data for ground information are lacking. Hyperspectral remote sensing combined with 1st derivative is an efficient tool for the identification of agricultural crops. In our study, we develop a system for hyperspectral analysis of the ground-based reflectance spectrum, which is monitored seven times during the cultivation period of three soybean crops using a PSR-2500 hyperspectral sensor. In the reflection spectrum of soybean canopy, wavelength variations correspond with stages of soybean growths. The spectral reflection characteristics of soybeans can be divided according to growth into the vegetative (V)stage and the reproductive (R)stage. As a result of the first derivative analysis of the spectral reflection characteristics, it is possible to identify the characteristics of each wavelength band. Using our developed monitoring system, we observed that the near-infrared (NIR) variation was largest during the vegetative (V1-V3) stage, followed by a similar variation pattern in the order of red-edge and visible. In the reproductive stage (R1-R8), the effect of the shape and color of the soybean leaf was reflected, and the pattern is different from that in the vegetative (V) stage. At the R1 to R6 stages, the variation in NIR was the largest, and red-edge and green showed similar variation patterns, but red showed little change. In particular, the reflectance characteristics of the R1 stage provides information that could help us distinguish between the three varieties of soybean that were studied. In the R7-R8 stage, close to the harvest period, the red-edge and NIR variation patterns and the visible variation patterns changed. These results are interpreted as a result of the large effects of pigments such as chlorophyll for each of the three soybean varieties, as well as from the formation and color of the leaf and stem. The results obtained in this study provide useful information that helps us to determine the wavelength width and range of the optimal band for monitoring and acquiring vegetation information on crops using satellites and unmanned aerial vehicles (UAVs)

Exosomes isolation from bovine serum: qualitative and quantitative comparison between ultracentrifugation, combination ultracentrifugation and size exclusion chromatography, and exoEasy methods

  • Eun-Yeong Bok;Sang Young Seo;Han Gyu Lee;Sudu Hakuruge Madusha Pramud Wimalasena;Eunju Kim;Ara Cho;Young-Hun Jung;Tai-Young Hur;Kyoung-Min So;Sung-Lim Lee;Yoon Jung Do
    • Journal of Animal Science and Technology
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    • v.66 no.5
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    • pp.1021-1033
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    • 2024
  • Exosomes have been extensively studied as disease biomarker in humans, given their role in transporting bioactive molecules. However, despite the great potential of exosomes as noninvasive diagnostic markers and therapeutic nanocarriers for bovine diseases, few studies have been conducted on bovine exosome. Thus, this study aimed to quantitatively and qualitatively compare three isolation methods to identify a suitable method for bovine serum. Exosomes were isolated using ultracentrifugation alone (UC), a combination of ultracentrifugation and size exclusion chromatography (US), or membrane affinity-based exoEasy kit (EE). Isolated particles were evaluated using a range of complementary techniques. Transmission electron microscopy showed that all three isolation methods resulted in particles with a cup-shaped morphology. The particle concentration measured by nanoparticle trafficking analyzer of US was lower compared to those of UC and EE method. As a result of immunoblotting, exosome markers including TSG101, CD81, and HSP70 were detected in US particles, while in UC and EE, only TSG101 expression was confirmed. Particles isolated from UC and EE showed a contamination with the blood protein albumin, whereas particles from US did not show albumin contamination. In addition, to evaluate the possibility of using exosomes as biomarkers, the profiles of the small RNA in the exosomes were compared using the bioanalyzer 2100. As a result, in the EE method, the band of small RNA (25-200 nt) was most prominent, and in the US methods, a distinct band was observed in the small RNA range. Collectively, the purity of exosomes without non-exosomal contamination was highest in the US method. However, for the detection of small RNA, the EE method was found to be the most suitable. Therefore, the results suggest that the optimal isolation method varies depending on the specific purpose of exosome isolation.

Analysis of Optimal Locations for Resource-Development Plants in the Arctic Permafrost Considering Surface Displacement: A Case Study of Oil Sands Plants in the Athabasca Region, Canada (지표변위를 고려한 북극 동토 지역의 자원개발 플랜트 건설 최적 입지 분석: 캐나다 Athabasca 지역의 오일샌드 플랜트 사례 연구)

  • Taewook Kim;YoungSeok Kim;Sewon Kim;Hyangsun Han
    • The Journal of Engineering Geology
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    • v.33 no.2
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    • pp.275-291
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    • 2023
  • Global warming has made the polar regions more accessible, leading to increased demand for the construction of new resource-development plants in oil-rich permafrost regions. The selection of locations of resource-development plants in permafrost regions should consider the surface displacement resulting from thawing and freezing of the active layer of permafrost. However, few studies have considered surface displacement in the selection of optimal locations of resource-development plants in permafrost region. In this study, Analytic Hierarchy Process (AHP) analysis using a range of geospatial information variables was performed to select optimal locations for the construction of oil-sands development plants in the permafrost region of southern Athabasca, Alberta, Canada, including consideration of surface displacement. The surface displacement velocity was estimated by applying the Small BAseline Subset Interferometric Synthetic Aperture Radar technique to time-series Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar images acquired from February 2007 to March 2011. ERA5 reanalysis data were used to generate geospatial data for air temperature, surface temperature, and soil temperature averaged for the period 2000~2010. Geospatial data for roads and railways provided by Statistics Canada and land cover maps distributed by the North American Commission for Environmental Cooperation were also used in the AHP analysis. The suitability of sites analyzed using land cover, surface displacement, and road accessibility as the three most important geospatial factors was validated using the locations of oil-sand plants built since 2010. The sensitivity of surface displacement to the determination of location suitability was found to be very high. We confirm that surface displacement should be considered in the selection of optimal locations for the construction of new resource-development plants in permafrost regions.

Antifungal Activity and Biochemical Characterization of Lectin Isolated from Locular Fluid of Cherry Tomato Fruit (방울토마토 열매 locular fluid lectin의 항균성과 생화학적 특성)

  • Roh, Kwang-Soo
    • KSBB Journal
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    • v.25 no.3
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    • pp.289-296
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    • 2010
  • Lectins are carbohydrate-binding and a cell-agglutinating proteins, and are concerted with a plants defence mechanism. In particular, chitin-binding lectins in locular fluid of cherry tomato fruit seemed to have a role in defending plants against fungi. The antifungal activity using lectin isolated from locular fluid of cherry tomato fruit was measured in the plant pathogen Cladosporium cucumerinum, Monosporascus cannonballus, Fusarium oxysporum, and Rhizoctonia solani. Amoung the four strains, a potent antifungal activity was detected in Cladosporium cucumerinum and Monosporascus cannonballus, not in Fusarium oxysporum, and Rhizoctonia solani. The molecular weight of this lectin isolated as double protein bands by SDS-PAGE was calculated to be 87 kDa and 47 kDa from the relative mobilities compared with those of reference molecular weight markers. The isolated lectin agglutinated human red blood cells (A, B, AB, O) treated with trypsin, and the most activity was found at B. The optimal temperature of isolated lectin was at $30^{\circ}C$. For the thermal stability, lectin was stable at $20-80^{\circ}C$. The optimal pH of this lectin was at 7.2, and showed complete loss below pH 9.0.

Analysis on Topographic Normalization Methods for 2019 Gangneung-East Sea Wildfire Area Using PlanetScope Imagery (2019 강릉-동해 산불 피해 지역에 대한 PlanetScope 영상을 이용한 지형 정규화 기법 분석)

  • Chung, Minkyung;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.36 no.2_1
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    • pp.179-197
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    • 2020
  • Topographic normalization reduces the terrain effects on reflectance by adjusting the brightness values of the image pixels to be equal if the pixels cover the same land-cover. Topographic effects are induced by the imaging conditions and tend to be large in high mountainousregions. Therefore, image analysis on mountainous terrain such as estimation of wildfire damage assessment requires appropriate topographic normalization techniques to yield accurate image processing results. However, most of the previous studies focused on the evaluation of topographic normalization on satellite images with moderate-low spatial resolution. Thus, the alleviation of topographic effects on multi-temporal high-resolution images was not dealt enough. In this study, the evaluation of terrain normalization was performed for each band to select the optimal technical combinations for rapid and accurate wildfire damage assessment using PlanetScope images. PlanetScope has considerable potential in the disaster management field as it satisfies the rapid image acquisition by providing the 3 m resolution daily image with global coverage. For comparison of topographic normalization techniques, seven widely used methods were employed on both pre-fire and post-fire images. The analysis on bi-temporal images suggests the optimal combination of techniques which can be applied on images with different land-cover composition. Then, the vegetation index was calculated from the images after the topographic normalization with the proposed method. The wildfire damage detection results were obtained by thresholding the index and showed improvementsin detection accuracy for both object-based and pixel-based image analysis. In addition, the burn severity map was constructed to verify the effects oftopographic correction on a continuous distribution of brightness values.

Purification and properties of a basic inducible protein, ICG with chitinase and ${\beta}-1,3-glucanase$ activities from rice cell suspension culture media treated with chitooligosaccharides (Chitooligosaccharides 처리에 의해 유도되는 chitinase, ${\beta}-1,3-glucanase$ 활성 보유 벼 염기성 단백질 ICG의 분리 및 성질)

  • Um, Sung-Yon;Park, Hee-Young;Kim, Su-Il
    • Applied Biological Chemistry
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    • v.37 no.1
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    • pp.43-48
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    • 1994
  • A basic inducible protein, ICG, containing chitinase and ${\beta}-1,3-glucanase$ activity concomittantly was purified from cell suspension culture media of rice after the treatment of chitooligosaccharides. The isolated ICG enzyme gave a single band on native and SDS polyacrylamide gel electrophoresis and its molecular weight was estimated to be 52.53 kd. The optimal temperature and optimal pH of both enzyme activities in ICG were $60^{\circ}C$, pH 6.0 for chitinase activity and $37^{\circ}C$, pH 4.0 for ${\beta}-1,3-glucanase$ activity. $K_M$ and $V_{max}$ values for chitinase were 0.474 mM. 2.997 nM/min., and those for ${\beta}-1,3-glucanase$ were 1.004 mM 0.739 nM/min. respectively. TLC analysis of the chitooligosaccharide hydrolysates with ICG enzyme indicated that ICG acts as endochitinase.

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Discrimination between Earthquakes and Explosions Recorded by the KSRS Seismic Array in Wonju, Korea (원주 KSRS 지진 관측망에 기록된 지진과 폭발 식별 연구)

  • Jeong, Seong Ju;Che, Il-Young;Kang, Tae-Seob
    • Geophysics and Geophysical Exploration
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    • v.17 no.3
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    • pp.137-146
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    • 2014
  • This study presents a procedure for discrimination of artificial events from earthquakes occurred in and around the Korean Peninsula using data set in the Wonju KSRS seismograph network, Korea. Two training sets representing natural and artificial earthquakes were constructed with 150 and 56 events, respectively, with high signal to noise ratio. A frequency band, Pg(4-6 Hz)/Lg(5-7 Hz), which is optimal for the discrimination of seismic sources was derived from the two-dimensional grid of Pg/Lg spectral amplitude ratio. The corrections for the effects of earthquake magnitude and hypocentral distance were carried out for improvement of discrimination capability. For correcting the effect of magnitude dependence due to the inverse proportionality of corner frequency to seismic moment, the Brune's source spectrum was subtracted from the observation spectrum. The spectrum was corrected using the optimal damping coefficient to remove damping effect with the hypocentral distance. The effect of locally varying spectrum ratio was cancelled correcting variation of wave propagation along the ray path. The performance in discrimination between training sets of natural and artificial events was compared using the Mahalanobis distance in each step of correction. The procedure of magnitude, distance, and path corrections show clear improvements of the discrimination results with increasing Mahalanobis distance, from 1.98 to 3.01, between two training sets.

Comparisons of Physiological Characteristics in Coriolus versicolor Intraspecific Strains (한국산 구름버섯의 균주간(菌株間) 생리적(生理的) 특성(特性) 비교(比較))

  • Park, Young-Do;Whang, Wan-Kyunn;Huh, Jae-Doo;Kim, Seong-Hwan;Park, Won-Mok
    • The Korean Journal of Mycology
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    • v.17 no.1
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    • pp.7-13
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    • 1989
  • This study was executed to investigate characterization of physiological genetic in Coriolus versicolor, basidiomycetes. The optimal media for mycelia culture were PDA, CVT-I and MES as solid media, 927 and CVT-III were good as liquid media, respectively. The optimal condition for mycelial culture was pH 5.6 and $25-30^{\circ}C$. Electrophoretic isozymes and protein patterns from mycelia identified very similar in 16001 and KD88001 strain, but the other species were very diffrent in band patterns. Especially, pattern of esterase seemed to be valuable tool as taxonomic techniques for indentifying species of Coriolus versicolor. Fruiting body was cultivated with artificial logs cultivation method; 16001 and KD88001 were very similar to fruiting body shapes and colours but 16001 and CVT-80 were different in their shapes, colours and making primordia. Therefore, 16001 and KD88001 were assumed to the same strain, but 16001, 16002 and CVT-80 had the different genetic background.

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The Study on Optimal Image Processing and Identifying Threshold Values for Enhancing the Accuracy of Damage Information from Natural Disasters (자연재해 피해정보 산출의 정확도 향상을 위한 최적 영상처리 및 임계치 결정에 관한 연구)

  • Seo, Jung-Taek;Kim, Kye-Hyun
    • Spatial Information Research
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    • v.19 no.5
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    • pp.1-11
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    • 2011
  • This study mainly focused on the method of accurately extracting damage information in the im agery change detection process using the constructed high resolution aerial im agery. Bongwha-gun in Gyungsangbuk-do which had been severely damaged from a localized torrential downpour at the end of July, 2008 was selected as study area. This study utilized aerial im agery having photographing scale of 30cm gray image of pre-disaster and 40cm color image of post-disaster. In order to correct errors from the differences of the image resolution of pre-/post-disaster and time series, the prelim inary phase of image processing techniques such as normalizing, contrast enhancement and equalizing were applied to reduce errors. The extent of the damage was calculated using one to one comparison of the intensity of each pixel of pre-/post-disaster im aged. In this step, threshold values which facilitate to extract the extent that damage investigator wants were applied by setting difference values of the intensity of pixel of pre-/post-disaster. The accuracy of optimal image processing and the result of threshold values were verified using the error matrix. The results of the study enabled the early exaction of the extents of the damages using the aerial imagery with identical characteristics. It was also possible to apply to various damage items for imagery change detection in case of utilizing multi-band im agery. Furthermore, more quantitative estimation of the dam ages would be possible with the use of numerous GIS layers such as land cover and cadastral maps.