• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1407-1419
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• 2020

Long time-series gridded data is crucial for the analyses of Earth environmental changes. Climate reanalysis and satellite images are now used as global-scale periodical and quantitative information for the atmosphere and land surface. This paper examines the feasibility of DCT-PLS (penalized least square regression based on discrete cosine transform) for the spatial gap filling of gridded data through the experiments for multiple variables. Because gap-free data is required for an objective comparison of original with gap-filled data, we used LDAPS (Local Data Assimilation and Prediction System) daily data and MODIS (Moderate Resolution Imaging Spectroradiometer) monthly products. In the experiments for relative humidity, wind speed, LST (land surface temperature), and NDVI (normalized difference vegetation index), we made sure that randomly generated gaps were retrieved very similar to the original data. The correlation coefficients were over 0.95 for the four variables. Because the DCT-PLS method does not require ancillary data and can refer to both spatial and temporal information with a fast computation, it can be applied to operative systems for satellite data processing.

• The Journal of the Korea Contents Association
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• v.12 no.11
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• pp.469-481
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• 2012

The demand for small-sized housing has been increasing due to the recession of real-estate price and the increase of small-sized households. Especially, the demand for affordable housing has been increasing since the style of housing and the location fits the lifestyle of small-sized household. In addition, many investors have been buying it because it has advertised as an investment property holding high-return ratio. However, an empirical analysis about the selling price and the return ratio has not been done yet. Therefore, the purpose of the research is having the empirical analysis based on the selling price and return ration by examining the affordable housing in Seoul. The urban-life housing more than 50 generations of the Seoul was irradiated for the analysis. And the linear regression analysis and PLS(Partial Least Square Regression) analysis was used for the empirical analysis. The result of analysis, based on the linear regression analysis, showed that factors including neighboring housing price and subway catchment area have a significant effect to the determinant factors of housing price. The analysis for return ratio showed neighboring housing price, subway catchment area and amenities affects the ratio. Especially, the fault of using small sample was covered by using the partial least square regression in this research.

• The Korean Journal of Applied Statistics
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• v.21 no.2
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• pp.275-290
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• 2008

The size of microarray gene expression data is very big and its observation process is also very complex. Thus missing values are frequently occurred. In this paper we propose the sequential partial least squares(SPLS) regression fitting method to estimate missing values for time course gene expression data that has correlations among observations over time points. The SPLS method is to combine the sequential technique with the partial least squares(PLS) regression fitting method. The usefulness of method proposed is evaluated through some simulation study for three yeast time course data.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.259-265
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• 2004

A quicker method was developed for foliar analysis in diagnosis of nitrogen in apple trees based on multivariate calibration procedure using partial least squares regression (PLSR) and principal component regression (PCR) to establish the relationship between reflectance spectra in the near infrared region and nitrogen content of fresh- and dry-leaf. Several spectral pre-processing methods such as smoothing, mean normalization, multiplicative scatter correction (MSC) and derivatives were used to improve the robustness and performance of the calibration models. Norris first derivative with a seven point segment and a gap of six points on MSC gave the best result of partial least squares-1 PLS-1) model for dry-leaf samples with root mean square error of prediction (RMSEP) equal to $0.699g\;kg^{-1}$, and that the Savitzky-Golay first derivate with a seven point convolution and a quadratic polynomial on MSC gave the best results of PLS-1 model for fresh-samples with RMSEP of $1.202g\;kg^{-1}$. The best PCR model was obtained with Savitzky-Golay first derivative using a seven point convolution and a quadratic polynomial on mean normalization for dry leaf samples with RMSEP of $0.553g\;kg^{-1}$, and obtained with the Savitzky-Golay first derivate using a seven point convolution and a quadratic polynomial for fresh samples with RMSEP of $1.047g\;kg^{-1}$. The results indicate that nitrogen can be determined by the near infrared reflectance (NIR) technology for fresh- and dry-leaf of apple.

• Food Science and Preservation
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• v.12 no.6
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• pp.608-612
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• 2005

Fourier transform-near infrared (FT-NIR) spectroscopy is a simple, rapid, non-destructive technique which can be used to make quantitative analysis of chemical composition in grain. An interest in total dietary fiber (TDF) of grain such as rice has been increased due to its beneficial effects for health. Since measuring methods for TDF content were highly depending on experimental technique and time consumptions, the application of FT-NIR spectroscopy to determine TDF content in milled rice. Results of enzymatic-gravimetric method were $1.17-1.92\%$ Partial least square (PLS) regression on raw NIR spectra to predict TDF content was developed Accuracy of prediction model for TDF content was certified for regression coefficient (r), standard error of estimation (SEE) and standard error of prediction (SEP). The r, SEE and SEP were 0.9705, 0.0464, and 0.0604, respectively. The results indicated that FT-NIR techniques could be very useful in the food industry and rice processing complex for determination of TDF in milled rice on real time analysis.

• The Korean Journal of Applied Statistics
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• v.30 no.5
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• pp.633-645
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• 2017

This study proposes a statistical procedure for analyzing container ship operation data that can help determine fuel consumption patterns. We first investigate the features that affect fuel consumption and develop the prediction model to find current fuel consumption. The ship data can be divided into two-type data. One set of operation data includes sea route, voyage information, longitudinal water speed, longitudinal ground speed, and wind, the other includes machinery data such as engine power, rpm, fuel consumption, temperature, and pressure. In this study, we separate the effects of external force on ships according to Beaufort Scale and apply a partial least squares regression to develop a prediction model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2495-2504
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• 2015

This study was performed in order to contributing the conflict factors which largely affects the efficient promotion of Urban Rehabilitation Project. then, it aims to induce conflict factors which affect the business period and business expense through PLS Regression Analysis. The data was build up from union members, tenants and merchants who are living in the completed urban rehabilitation area. In the case of 'Business period', it shows the priority on conflict factors in this order such as the 'Approval and Authorization for union establishment', 'Approval and Plan for business enforcement' and 'Interruption of interest group related to service business such as business delay'. In addition, In the case of 'Business expenses', it shows the priority on conflict factors in this order such as the 'Approval and Authorization for union establishment', 'Selling contract', 'Report of Demolition and Loss' and 'Plan and Authorization of Management disposition'.

• Journal of Korea Planning Association
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• v.54 no.3
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• pp.5-14
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• 2019

Starting with the market vitalization project in 2008, The Gwangju Dae-in Art Market has attracted to many artists, changing into cultural and art market. After the project was carried out for a certain period of time, a study was conducted to determine the differing opinions of the artists and merchants in regards to the market. The study also examined and analyzed the factors affecting the artists' continuous activities. The difference in recognition perception between artists and merchants was analyzed through a T-test. PLS-regression analysis was used for the artists' continuing intention to work. As a result, the artists and merchants recognized that the number of visitors increased after the influx of artists. Programs that had a positive impact on the artist's intention for sustainable activities were as follows: the 'Art Products Creation Workshop', where artists, merchants, and citizens collaborate to develop commodities needed for the market; 'Hanpyeong Gallery', where artists directly or indirectly interact with merchants and citizens; the 'Artist-Merchant Workshop', where artists and merchants produce articles required for the market; 'C'est Si Bon', which expresses the placeness of the market into art; and the 'Dae-in Art Night Market', where citizens, merchants and visitors can sell their own works. On the other hand, programs with the negative effect were those where artists' participation was low or none, as the policy implications, they should be actively develop this type of programs, where artists could participate and interact with citizens and merchants, like this visitors and sales can be increased.

• Journal of Biosystems Engineering
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• v.22 no.3
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• pp.333-342
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• 1997

The objective of this research was to develop model equations for measuring rice milling ratio by using visible / HIR spectroscopy. Twelve kinds of brown rice(n = 149) were milled to obtain various milling ratio ranged from 86% to 94%. Visible/NIR spectra were collected with a spectrophotometer with sample transport module. The reflectance and transmission spectra were measured in the range of 400~2, 500nm and 600~1, 400nm, respectively, with 2 nm intervals. Multiple linear regression(MLR), Partial least square (PLS), and Artificial neural network(ANN) were used to develop models. Model developed with reflectance spectra showed better prediction results then those with transmission spectra. The MLR model with six-wavelength obtained from first derivative spectra gave to the best results for measuring the rice milling ratio(SEP = 0.535, , $r^2$ = 0.980). The PLS model(SEP = 0.604, $r^2$= 0.976) and ANN model(SEP = 0.566, $r^2$= 0.978) also can be used to determine the rice milling ratio effectively.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.580-583
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• 2005

We have evaluated the application of spectroscopy using an insertion-type fiber-optic probe and a sensor at wavelengths from 400 to 1,100 nm to the measurement of milk fat content on dairy farms. The internal reflectance ratios of 183 milk samples were determined with a fiber-optic spectrophotometer at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$. Partial least squares (PLS) regression was used to develop calibration models for the milk fat. The best accuracy of determination was found for an equation that was obtained using smoothed internal reflectance data and three PLS factors at 20$^{\circ}C$. The correlation coefficients between predicted and reference milk fat at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$ were r=0.753, r=0.796 and r=0.783, respectively. The predictive explained variances ($Q^2$) of the final model, moreover, were more than 0.550 at all temperatures, and the regression coefficients of determination ($R^2$) were more than 0.6 (60%). Our results indicate that milk has different internal reflectance measured in the range of visible and near infrared wavelengths (400 to 1,100 nm), depending on its fat content.