• 제목/요약/키워드: Spectral studies

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Synthesis of New VO(II), Co(II), Ni(II) and Cu(II) Complexes with Isatin-3-Chloro-4-Floroaniline and 2-Pyridinecarboxylidene-4-Aminoantipyrine and their Antimicrobial Studies

  • Mishra, Anand P.;Mishra, Rudra;Jain, Rajendra;Gupta, Santosh
    • Mycobiology
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    • v.40 no.1
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    • pp.20-26
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    • 2012
  • The complexes of tailor made ligands with life essential metal ions may be an emerging area to answer the problems of multi drug resistance. The coordination complexes of VO(II), Co(II), Ni(II) and Cu(II) with the Schiff bases derived from isatin with 3-chloro-4-floroaniline and 2-pyridinecarboxaldehyde with 4-aminoantipyrine have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, molar conductance, electronic spectra, FT-IR, FAB mass and magnetic susceptibility measurements. FAB mass data show degradation of complexes. Both the ligands behave as bidentate and tridentate coordinating through O and N donor. The complexes exhibit coordination number 4, 5 or 6. The Schiff base and metal complexes show a good activity against the bacteria; $Staphylococcus$ $aureus$, $Escherichia$ $coli$ and $Streptococcus$ $fecalis$ and fungi $Aspergillus$ $niger$, $Trichoderma$ $polysporum$, $Candida$ $albicans$ and $Aspergillus$ $flavus$. The antimicrobial results also indicate that the metal complexes are better antimicrobial agents as compared to the Schiff bases. The minimum inhibitory concentrations of the metal complexes were found in the range 10-40 ${\mu}g/mL$.

Accuracy Assessment of Supervised Classification using Training Samples Acquired by a Field Spectroradiometer: A Case Study for Kumnam-myun, Sejong City (지상 분광반사자료를 훈련샘플로 이용한 감독분류의 정확도 평가: 세종시 금남면을 사례로)

  • Shin, Jung Il;Kim, Ik Jae;Kim, Dong Wook
    • Journal of Korean Society for Geospatial Information Science
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    • v.24 no.1
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    • pp.121-128
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    • 2016
  • Many studies are focused on image data and classifier for comparison or improvement of classification accuracy. Therefore studies are needed aspect of the training samples on supervised classification which depend on reference data or skill of analyst. This study tries to assess usability of field spectra as training samples on supervised classification. Classification accuracies of hyperspectral and multispectral images were assessed using training samples from image itself and field spectra, respectively. The results shown about 90% accuracy with training sample collected from image. Using field spectra as training sample, accuracy was decreased 10%p for hyperspectral image, and 20%p for multispectral image. Especially, some classes shown very low accuracies due to similar spectral characteristics on multispectral image. Therefore, field spectra might be used as training samples on classification of hyperspectral image, although it has limitation for multispectral image.

Application of Normalized Vegetation Index for Estimating Hydrological Factors in the Korea Peninsula from COMS (한반도 지역에서의 수문인자산정을 위한 식생 정보 분석 및 활용 ; 천리안 위성을 이용하여)

  • Park, Jongmin;Baik, Jongjin;Kim, Seong-Joon;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.47 no.10
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    • pp.935-943
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    • 2014
  • Normalized Difference Vegetation Index (NDVI) used as input data for various hydrologic models plays a key role in understanding the variation of Hydrometeological parameters and Interaction between surface and atmosphere. Many studies have been conducted to estimate accurate remotely-sensed NDVI using spectral characteristics of vegetation. In this study, we conducted comparative analysis between Communication, Ocean and Meteorological Satellite and MOderate-Resolution Imaging Spectroradiometer (MODIS) NDVI. For comparison, Maximum Value Composite (MVC) was used to estimate 8-day and 16-day composite COMS NDVI. Both 8-day and 16-day COMS NDVI showed high statistical results compared with MODIS NDVI. Based on the results in this study, it can be concluded that COMS can be widely applicable for further ecological and hydrological studies.

Multi-temporal Remote Sensing Data Analysis using Principal Component Analysis (주성분분석을 이용한 다중시기 원격탐사 자료분석)

  • Jeong, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.3
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    • pp.71-80
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    • 1999
  • The aim of the present study is to define and tentatively to interpret the distribution of polluted water released from Lake Sihwa into the Yellow Sea using Landsat TM. Since the region is an extreme Case 2 water, empirical algorithms for detecting concentration of chlorophyll-a and suspended sediments have limitations. This work focuses on the use of multi-temporal Landsat TM data. We applied PCA to detect evolution of spatial feature of polluted water after release from the lake Sihwa. The PCA results were compared with in situ data, such as chlorophyll-a, suspended sediments, Secchi disk depth(SDD), surface temperature, remote sensing reflectance at six channel of SeaWiFS. Also, the in situ remote sensing reflectance obtained by PRR-600(Profiling Reflectance Radiometer) was compared with PCA results of Landsat TM data sets to find good correlation between first Principal Component and Secchi disk depth($R^2$=0.7631), although other variables did not result in such a good correlation. Therefore, Problems in applying PCA techniques to multi-spectral remotely sensed data were also discussed in this paper.

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Establishment of Geometric Correction Data using LANDSAT Satellite Images over the Korean Peninsular (한반도지역 LANDSAT 위성영상의 기하보정 데이터 구축)

  • Yoon, Geun-Won;Park, Jeong-Ho;Chae, Gee-Ju;Park, Jong-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.1
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    • pp.98-106
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    • 2003
  • Because satellite images have the advantage of high resolution, multi-spectral, revisit and wide swath characteristics, it is increased to utilize satellite image and get information little by little in nowadays. In order to utilize remote sensed images effectively, it is necessary to process satellite images through many processing steps. Among them, geometric correction is essential step for satellite image processing. In this study, we constructed geometric correction data using LANDSAT satellite images. First, we extracted GCPs from maps and constructed database over the Korean peninsular. Second, LANDSAT satellite images, 165 scenes were corrected geometrically using GCP database. Finally, we made 7 mosaic images by means of geometric correction images over Korean peninsular. We think that constructed geometric correction data will be used for many application fields as basic data.

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Clinical Implications of EEG and ERP as Biological Markers for Alzheimer's Disease and Mild Cognitive Impairment (경도인지장애와 알츠하이머병 치매의 생물학적 표지자로서 뇌파와 사건유발전위의 임상적 의미)

  • Kim, Chang Gyu;Kim, Hyun-Taek;Lee, Seung-Hwan
    • Korean Journal of Biological Psychiatry
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    • v.20 no.4
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    • pp.119-128
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    • 2013
  • Objectives Memory impairment is a very important mental health issue for elderly and adults. Mild cognitive impairment (MCI) is a prodromal stage of Alzheimer's disease (AD). Early detection of the prodromal stage of patients with AD is an important topic of interest for both mental health clinicians and policy makers. Methods Electroencephalograpgy (EEG) has been used as a possible biological marker for patients with MCI, and AD. In this review, we will summarize the clinical implications of EEG and ERP as a biological marker for AD and MCI. Results EEG power density, functional coupling, spectral coherence, synchronization, and connectivity were analyzed and proved their clinical efficacy in patients with the prodromal stage of AD. Serial studies on late event-related potentials (ERPs) were also conducted in MCI patients as well as healthy elders. Even though these EEG and ERP studies have some limitations for their design and method, their clinical implications are increasing rapidly. Conclusion EEG and ERP can be used as biological markers of AD and MCI. Also they can be used as useful tools for early detection of AD and MCI patients. They are useful and sensitive research tools for AD and MCI patients. However, some problems remain to be solved until they can be practical measures in clinical setting.

A Study on the Application of IHS Transformation Technique for the Enhancement of Remotely Sensed Data Classification (리모트센싱 데이터의 분류향상을 위한 IHS 변환기법 적용)

  • Yeon, Sangho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.1 no.1
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    • pp.109-117
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    • 1998
  • To obtain new information using a single remotely sensed image data is limited to extract various information. Recent trends in the remote sensing show that many researchers integrate and analyze many different forms of remotely sensed data, such as optical and radar satellite images, aerial photograph, airborne multispectral scanner data and land spectral scanners. Korean researchers have not been using such a combined dataset yet. This study intended to apply the technique of integration between optical data and radar data(SAR) and to examine the output that had been obtained through the technique of supervised classification using the result of integration. As a result, we found of better enhanced image classification results by using IHS conversion than by using RGB mixed and interband correlation.

Studies on Identification of the Anthocyanins in Elderberries (Sambucus) (Elderberry(Sambucus) Anthocyanin에 관한 연구(硏究))

  • Shin, Mal-Shick;Ahn, Seung-Yo
    • Korean Journal of Food Science and Technology
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    • v.12 no.4
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    • pp.305-312
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    • 1980
  • Studies have been carried out on the structure and the content of the anthocyanins in elderberries which were just recently transplanted in Korea. The anthocyanin pigments of elderberries were extracted with 1 % methanolic HCl and purified with Amberlite IRC-50 cation exchange column. The individual pigments were isolated by paper chromatography. Five pigments, identified by various chemical and physical methods were cyanidin-3-monoglucoside(4.3%), cyanidin-3,5-diglucoside(28.3%), cyanidin-3,5-diglucoside with p-coumaric arid(12.9%), cyanidin-3-xyloglucoside-5-glucoside(38.3%), cyanidin-3-xyloglucoside-5-glucoside with p-coumaric acid(16.2%). The content of total anthocyanin in elderberry was 3.13 mg/g fresh weight.

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Principal Component Transformation of the Satellite Image Data and Principal-Components-Based Image Classification (위성 영상데이터의 주성분변환 및 주성분 기반 영상분류)

  • Seo, Yong-Su
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.4
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    • pp.24-33
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    • 2004
  • Advances in remote sensing technologies are resulting in the rapid increase of the number of spectral channels, and thus, growing data volumes. This creates a need for developing faster techniques for processing such data. One application in which such fast processing is needed is the dimension reduction of the multispectral data. Principal component transformation is perhaps the mostpopular dimension reduction technique for multispectral data. In this paper, we discussed the processing procedures of principal component transformation. And we presented and discussed the results of the principal component transformation of the multispectral data. Moreover principal components image data are classified by the Maximum Likelihood method and Multilayer Perceptron method. In addition, the performances of two classification methods and data reduction effects are evaluated and analyzed based on the experimental results.

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Derivation of response spectrum compatible non-stationary stochastic processes relying on Monte Carlo-based peak factor estimation

  • Giaralis, Agathoklis;Spanos, Pol D.
    • Earthquakes and Structures
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    • v.3 no.5
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    • pp.719-747
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    • 2012
  • In this paper a novel approach is proposed to address the problem of deriving non-stationary stochastic processes which are compatible in the mean sense with a given (target) response (uniform hazard) spectrum (UHS) as commonly desired in the aseismic structural design regulated by contemporary codes of practice. The appealing feature of the approach is that it is non-iterative and "one-step". This is accomplished by solving a standard over-determined minimization problem in conjunction with appropriate median peak factors. These factors are determined by a plethora of reported new Monte Carlo studies which on their own possess considerable stochastic dynamics merit. In the proposed approach, generation and treatment of samples of the processes individually on a deterministic basis is not required as is the case with the various "two-step" approaches found in the literature addressing the herein considered task. The applicability and usefulness of the approach is demonstrated by furnishing extensive numerical data associated with the elastic design UHS of the current European (EC8) and the Chinese (GB 50011) aseismic code provisions. Purposely, simple and thus attractive from a practical viewpoint, uniformly modulated processes assuming either the Kanai-Tajimi (K-T) or the Clough-Penzien (C-P) spectral form are employed. The Monte Carlo studies yield damping and duration dependent median peak factor spectra, given in a polynomial form, associated with the first passage problem for UHS compatible K-T and C-P uniformly modulated stochastic processes. Hopefully, the herein derived stochastic processes and median peak factor spectra can be used to facilitate the aseismic design of structures regulated by contemporary code provisions in a Monte Carlo simulation-based or stochastic dynamics-based context of analysis.