• Title/Summary/Keyword: Principal Components Analysis (PCA)

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Assessment of Hydrogeochemical Characteristics and Contaminant Dispersion of Aquifer around Keumsan Municipal Landfill (금산 매립장 주변 대수층의 수리지화학적 특성 및 오염 확산 평가)

  • Oh, In-Suk;Ko, Kyung-Seok;Kong, In-Chul;Ku, Min-Ho
    • Economic and Environmental Geology
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    • v.41 no.6
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    • pp.657-672
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    • 2008
  • The purposes of this study are to investigate the hydrogeochemical characteristics of groundwaters around Keumsan municipal landfill, and to evaluate the contaminant dispersion from the landfill and its environmental impact. To achieve these goals, groundwater quality logging, hydrochemical analysis, multivariate statistical analysis, and contaminant transport modeling were performed. The water quality logging indicated a leaking from the landfill at the depth of 4-12m around a leachate sump. Electrical conductivity data indicated that groundwaters within 70-100m from landfill were affected by the landfill leakage. Principal components 1 and 2 obtained from principal components analysis (PCA) reflect the influence of leachate and the characteristics of aquifer media, respectively. The results of principal component analysis also indicated the natural attenuation processes such as cation exchange, sorption, and microbial biodegradation. The modeling results showed that groundwater flow westward along a valley from the landfill and contaminants transport accordingly.

A Case Study on the Evaluation of Environmental Health Status based on Environmental Health Indicators (환경보건지표를 이용한 지역 환경보건수준 평가 사례연구)

  • Jung, Soon-Won;Lee, Young-Mee;Hong, Sung-Joon;Chang, Jun-Young;Yu, Seung-Do;Choi, Kyung-Hee;Park, Choong-Hee
    • Journal of Environmental Health Sciences
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    • v.42 no.5
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    • pp.302-313
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    • 2016
  • Objectives: This study was conducted to assess environmental health status on a local scale using environmental health-related indicators. It demonstrated the possibility of using a structural equation model, a methodological approach to provide synthesized information. Methods: Eighteen indicators were selected from official statistical data published by local governments. Each environmental health-related indicator was classified according to the PSR (pressure-state-response) model. Aggregation methods were performed using principal component analysis and fuzzy sets. Results: The five principal components were classified through principal component analysis (PCA) and obtained eigenvalues >1.0 from the initial 18 indicators. The aggregated index was obtained by condensing the original information into two broad and simple categories through fuzzy sets. Conclusion: This could be useful in that the aggregation procedure may provide a basis for establishing environmental health policies and a decision-making process. However, the availability and quality of indicators, assessment of aggregation method bias, choice of weighted scores for indicators, and other factors should be examined in future studies.

The Factor Clustering of Growing Stock Changes by Forest Policy using Principal Component Analysis (주성분 분석을 이용한 산림정책별 입목축적변화의 요인 군집)

  • Shin, Hye-Jin;Kim, Eui-Gyeong;Kim, Dong-Hyeon;Kim, Hyeon-Guen
    • Journal of agriculture & life science
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    • v.46 no.2
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    • pp.1-8
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    • 2012
  • This study is a precedent study for deriving transfer function model between growing stock and forest management policies. Its goal is to solve the multicollinearity between forest works inducing growing stock changes through principal component analysis using annual time series data from 1997 to 2008. As the results, the total explanatory power showed 91.4% on the summarized 3 principal components. They were renamed 'good forest management' 'pest & insets management' 'forest fires' for conceptualization on the derived each component.

LANDSAT remotely sensed data's Classification accuracy improvement Using Standardized Principal Components Analysis (표준화 주성분 분석(Standardized PCA)을 이용한 LANDSAT 위성자료 분류 (Classification)의 정확도 향상)

  • 장훈;윤완석
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2003.04a
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    • pp.151-156
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    • 2003
  • 본 연구에서는 2000년 LANDSAT ETM+ 수도권 영상을 이용하여 도시지역 10개소, 식생지역 10개소를 선정해서 각각에 대해 표준화 주성분 분석을 적용하여 두 지역간의 고유벡터 매트릭스를 비교ㆍ분석해보았다. 도시 지역과 식생 지역각각에 대해 총 6개의 주성분이 생성되었으며 PC-2와 고유벡터 부호가 변한 밴드(band2, band7)를 RGB로 조합하여 수원지역을 대상으로 분류(Classification)한 결과의 정확도를 분광서명 분별 분석(Signature Separability Analysis)통해 얻은 밴드조합(band1, band3, band5) 영상의 분류결과와 비교해 보았다. 수원지역 2000년 IKONOS 영상의 다중분광 밴드(4×4m)와 전정색 밴드(1x1m)를 융합한 영상이 분류 정확도를 판단하는 기준으로 사용되었다. 비교결과 분류 전체 정확도는 각각 87.7%, 77.29% Khat 지수는 0.83, 0.68로 나타나 PC-2, 밴드2, 밴드7을 이용했을 때 분류 정확도를 높일 수 있다는 결과를 얻었다.

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Profiling Patterns of Volatile Organic Compounds in Intact, Senescent, and Litter Red Pine (Pinus densiflora Sieb. et Zucc.) Needles in Winter

  • CHOI, Won-Sil;YANG, Seung-Ok;LEE, Ji-Hyun;CHOI, Eun-Ji;KIM, Yun-Hee;YANG, Jiyoon;PARK, Mi-Jin
    • Journal of the Korean Wood Science and Technology
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    • v.48 no.5
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    • pp.591-607
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    • 2020
  • This study was aimed to investigate the changes of chemical composition of the volatile organic compounds (VOCs) emitted from red pine needles in the process of needle abscission or senescence. The VOCs in intact, senescent, and litter red pine needle samples were analyzed by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS). And then, multivariate statistical interpretation of the processed data sets was conducted to investigate similarities and dissimilarities of the needle samples. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to investigate the dataset structure and discrimination between samples, respectively. From the data preview, the levels of major components of VOCs from needles were not significantly different between needle samples. By PCA investigation, the data reduction according to classification based on the chlorophyll a / chlorophyll b (Ca/Cb) ratio were found to be ideal for differentiating intact, senescent, and litter needles. The following OPLS-DA taking Ca/Cb ratio as y-variables showed that needle samples were well grouped on score plot and had the significant discriminant compounds, respectively. Several compounds had significantly correlated with Ca/Cb ratio in a bivariate correlation analysis. Notably, the litter needles had a higher content of oxidized compounds than the intact needles. In summary, we found that chemical compositions of VOCs between intact, senescent, and litter needles are different each other and several compounds reflect characteristic of needle.

Design of Robust Face Recognition System Realized with the Aid of Automatic Pose Estimation-based Classification and Preprocessing Networks Structure

  • Kim, Eun-Hu;Kim, Bong-Youn;Oh, Sung-Kwun;Kim, Jin-Yul
    • Journal of Electrical Engineering and Technology
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    • v.12 no.6
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    • pp.2388-2398
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    • 2017
  • In this study, we propose a robust face recognition system to pose variations based on automatic pose estimation. Radial basis function neural network is applied as one of the functional components of the overall face recognition system. The proposed system consists of preprocessing and recognition modules to provide a solution to pose variation and high-dimensional pattern recognition problems. In the preprocessing part, principal component analysis (PCA) and 2-dimensional 2-directional PCA ($(2D)^2$ PCA) are applied. These functional modules are useful in reducing dimensionality of the feature space. The proposed RBFNNs architecture consists of three functional modules such as condition, conclusion and inference phase realized in terms of fuzzy "if-then" rules. In the condition phase of fuzzy rules, the input space is partitioned with the use of fuzzy clustering realized by the Fuzzy C-Means (FCM) algorithm. In conclusion phase of rules, the connections (weights) are realized through four types of polynomials such as constant, linear, quadratic and modified quadratic. The coefficients of the RBFNNs model are obtained by fuzzy inference method constituting the inference phase of fuzzy rules. The essential design parameters (such as the number of nodes, and fuzzification coefficient) of the networks are optimized with the aid of Particle Swarm Optimization (PSO). Experimental results completed on standard face database -Honda/UCSD, Cambridge Head pose, and IC&CI databases demonstrate the effectiveness and efficiency of face recognition system compared with other studies.

Spectroscopic Characterization of Wood Surface Treated by Low-Temperature Heating (저온 열처리 목재 표면의 분광학적 특성)

  • Kim, Kang-Jae;Nah, Gi-Baek;Ryu, Ji-Ae;Eom, Tae-Jin
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.3
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    • pp.285-296
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    • 2018
  • As a study for the verification of heat treated wood according to ISPM No. 15, the spectroscopic characteristics of the heat treated wood surface were analyzed. Various functional groups were observed on the IR spectrum, but it was difficult to find any particular difference between wood species, heat treatment time and storage period. HBI (hydrogen-bonding intensity) shows the change of the heat treated wood according to the storage time, but the change of wood with the heat treatment time was hard to be observed. On the PCA score plot, however, it was possible to sort the wood according to the heat treatment time of 60 minutes or 90 minutes in the species. The standards for classification of heat-treated wood in PCA were aromatic rings in lignin and C-H bending in cellulose, and these components were able to classify heat-treated wood by ISPM No. 15.

Predicting Soil Chemical Properties with Regression Rules from Visible-near Infrared Reflectance Spectroscopy

  • Hong, Suk Young;Lee, Kyungdo;Minasny, Budiman;Kim, Yihyun;Hyun, Byung Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.5
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    • pp.319-323
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    • 2014
  • This study investigates the prediction of soil chemical properties (organic matter (OM), pH, Ca, Mg, K, Na, total acidity, cation exchange capacity (CEC)) on 688 Korean soil samples using the visible-near infrared reflectance (VIS-NIR) spectroscopy. Reflectance from the visible to near-infrared spectrum (350 to 2500 nm) was acquired using the ASD Field Spec Pro. A total of 688 soil samples from 168 soil profiles were collected from 2009 to 2011. The spectra were resampled to 10 nm spacing and converted to the 1st derivative of absorbance (log (1/R)), which was used for predicting soil chemical properties. Principal components analysis (PCA), partial least squares regression (PLSR) and regression rules model (Cubist) were applied to predict soil chemical properties. The regression rules model (Cubist) showed the best results among these, with lower error on the calibration data. For quantitatively determining OM, total acidity, CEC, a VIS-NIR spectroscopy could be used as a routine method if the estimation quality is more improved.

Confocal Raman Spectrum Classification Using Fisher Measure based Filtering for Basal Cell Carcinoma Detection (기저세포암종 탐지를 위한 피셔척도 필터링 기반 공초점 라만 스펙트럼 분류)

  • Min So-Hui;Kim Jin-Yeong;Baek Seong-Jun;Na Seung-Yu;Ju Jae-Beom
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2006.05a
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    • pp.203-207
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    • 2006
  • This paper deals with a problem of detecting BCC using confocal raman spectrum. Specially, we propose Fisher measure based filtering for rejection of frequency components being noisy or non-discriminative. we use PCA (principal component analysis) for reduction of feature space dimension. Also, we apply MAP detector for classification of BCC raman spectrum. The experimental results shows that our proposed method can reduce the feature dimension and also raise the detection ratio.

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Evaluation of horticultural traits and genetic relationship in melon germplasm (멜론 유전자원의 원예형질 특성 및 유연관계 분석)

  • Jung, Jaemin;Choi, Sunghwan;Oh, Juyeol;Kim, Nahui;Kim, Daeun;Son, Beunggu;Park, Younghoon
    • Journal of Plant Biotechnology
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    • v.42 no.4
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    • pp.401-408
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    • 2015
  • Horticultural traits and genetic relationship were evaluated for 83 melon (Cucumis melo L.) cultivars. Survey of a total of 36 characteristics for seedling, leaf, stem, flower, fruit, and seed and subsequent multiple analysis of variance (MANOVA) were conducted. Principal component analysis (PCA) showed that 8 principle components including fruit weight, fruit length, fruit diameter, cotyledon length, seed diameter, and seed length accounted for 76.3% of the total variance. Cluster analysis of the 83 melon cultivars using average linkage method resulted in 5 clusters at coefficient of 0.7. Cluster I consisted of cultivars with high values for fruit-related traits, Cluster II for soluble solid content, and Cluster V for high ripening rate. Genotyping of the 83 cultivars was conducted using 15 expressed-sequence tagged-simple sequence repeat (EST-SSR) from the Cucurbit Genomics Initiative (ICuGI) database. Analysis of genetic relatedness by UPGMA resulted in 6 clusters. Mantel test indicated that correlation between morphological and genetic distance was very low (r = -0.11).