• YAKHAK HOEJI
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• v.47 no.3
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• pp.148-153
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• 2003

Skin moisture is an important factor in skin health. Measurement of moisture content can provide diagnostic information on the condition of skin. In this study, a portable near-infrared (NIR) system was newly integrated with a photo diode array detector that has no moving parts, and this system has been successfully applied for the evaluation of human skin moisture. Diffuse reflectance spectra were collected and transformed to absorbance using 1 nm step size over the wavelength range of 1100 nm to 2200 nm. Partial least squares regression (PLSR) was applied to develop a calibration model. For practical use for the evaluation of human skin moisture, the PLS model for human skin moisture was developed in vivo using the portable NIR system on the basis of the relative water content values of stratum corneum from the conventional capacitance method. The PLS model showed a good correlation. The calibration with the use of PLS model predicted human moisture with a standard error of prediction (SEP) of 3.5 at 1120∼1730 nm range. This study showed the possibility of skin moisture measurement using portable NIR system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2989-2996
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• 2014

The aim of this study was to search for the effects of health self-efficacy and technology self-efficacy on user's behavioural intention by the extended TAM focused on smartphone base ubiquitous health system. In this research, in view of small sample size, PLS - SEM methodology was applied to this study in order to the proposed research model. As a result of analysis, the statistical fitness of proposed research model was confirmed through GoF value and the path coefficient was calculated for the hypotheses test. Finally, the implications of analysis result showed that when the use of smartphone device could be easily accessed in the side of technology self-efficacy, the possibility of user's behavioural intention also might be higher.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.825-828
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• 2010

To classify Glycyrrhiza species, samples of different species were analyzed by $^1H$ NMR-based metabolomics technique. Partial least squares discriminant analysis (PLS-DA) was used as the multivariate statistical analysis of the 1H NMR data sets. There was a clear separation between various Glycyrrhiza species in the PLS-DA derived score plots. The PLS-DA model was validated, and the key metabolites contributing to the separation in the score plots of various Glycyrrhiza species were lactic acid, alanine, arginine, proline, malic acid, asparagine, choline, glycine, glucose, sucrose, 4-hydroxy-phenylacetic acid, and formic acid. The compounds present at relatively high levels were glucose, and 4-hydroxyphenylacetic acid in G. glabra; lactic acid, alanine, and proline in G. inflata; and arginine, malic acid, and sucrose in G. uralensis. This is the first study to perform the global metabolomic profiling and differentiation of Glycyrrhiza species using $^1H$ NMR and multivariate statistical analysis.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1133-1138
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• 2014

Ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI- MS/MS) provides a high-speed method to screen a large number of samples for small molecules with specific properties. In this study, UPLC-ESI-MS/MS with multiple reaction monitoring (MRM) was employed to screen urinary phospholipid (PL) content for biomarkers of prostate cancer. From lists of urinary PLs structurally identified using nanoflow LC-ESI-MS/MS, 52 PL species were selected for quantitative analysis in urine samples between 22 cancer-free urologic patients as controls and 45 prostate cancer patients. Statistical treatment of data by receiver operating characteristic (ROC) analysis yielded 14 PL species that differed significantly in relative concentrations (area under curve (AUC) > 0.8) between the two groups. Among PLs present at higher levels in prostate cancer urine, phosphatidylcholines (PCs) and phosphatidylinositols (PIs) constituted the major head group PLs (3 PCs and 7 PIs). For technical reasons, PL species of low abundance may be underrepresented in data from UPLC-ESI-MS/MS performed in MRM mode. However, the proposed method enables the rapid screening of large numbers of plasma or urine samples in the search for biomarkers of human disease.

• Journal of the Ergonomics Society of Korea
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• v.19 no.3
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• pp.23-37
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• 2000

Usability is one of the most important factors that affect customers' decision to purchase a product. Several studies have been conducted to model the relationship between the product design variables and the product usability. Since there could be hundreds of design variables to be considered in the model, a variable screening method is required. Traditional variable screening methods are based on expert opinions (Expert screening) in most Kansei engineering studies. Suggested in this study are statistical methods for screening important design variables by using the principal component regression(PCR), cluster analysis, and partial least squares(PLS) method. Product variables with high effect (PCR screening and PLS screening) or representative variables (Cluster screening) can be used to model the usability. Proposed variable screening methods are used to model the usability for 36 audio/visual products. The three analysis methods (PCR, Cluster, and PLS) show better model performance than the Expert screening in terms of $R^2$, the number of variables in the model, and PRESS. It is expected that these methods can be used for screening the product design variables efficiently.

• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.163-168
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• 1992

Results of magnetic measurement of a prototype Storage Ring dipole magnet for the Pohang Light Source (PLS) are summarized. Hall probe mapping and rotating coil methods are used to measure field profiles and integrated field properties. End chamfering experiments are performed on the as-built magnet, which has four removable pole-end pieces, to meet the specifications set from beam dy-namics requirement. The corrected magnet has efficiency of 99.7% at 2.0 GeV excitation ad higher order multipole error levels less than the specifications for all excitations, showing that the magnet has appropriate properties for the PLS Storage Ring.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.168-171
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• 2006

After an incandescent lamp developed as a first light source using electric energy in 1879, various lamps have been developed and promoted for usual convenience. Although lots of light sources have been developed for the past centry, among them some were used widely but some were hardly used contray to the initial expectations. Incandescent, fluorescent, HID and LED lamps which are normally used these days were treated as new type of light sources and very difficult to be popularized at the initial stage. In spite of the initial difficulties, these light sources and luminaries are still so popular because all of them were improved to be used easily by reflecting human's mental and physiological state. Like this when new light sources and luminaries are developed, a careful consideration, if these are proper for the surroundings or not, must be preceded. This study finally derived development factors of PLS developed in domestic to be played an important role in future light by analyzing product trends, social and lighting development changes.

• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.13-25
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• 2017

This study is quantitative reconstruction of palaeo sea level records around Sinduk-ri, Gochang-Gun. 7 cores were collected from GC14 to GC18 in order to examine the entire sedimentary facies and reconstruct the sea level records. The cores were analysed by AMS, sedimentary facies, diatom and WA-pls. As a result of the diatom analysis, diatom zone were classified as No diatom zone, B1 zone, M zone and B2 zone. The result of WA-pls was that the sea level was about 1.5m lower than the present level around 6,000 BP and about 1m lower during last 5,000 BP. Thereafter, sea level rose to the present during the Mc sub-diatom zone period. Moreover, during the Md sub-diatom zone period, sea level was about 0.5m higher than the present.

• Journal of the Korean Society of Safety
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• v.34 no.4
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• pp.59-67
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• 2019

Since it is really hard to construct process models based on prior process knowledges, various statistical approaches have been employed to build fault diagnosis models. However, the crucial drawback of these approaches is that the solutions may vary according to the fault magnitude, even if the same fault occurs. In this study, the parameter monitoring approach is suggested. When a fault occurs in a chemical process, this leads to trigger the change of a process model and the monitoring parameters of process models is able to provide the efficient fault diagnosis model. A few important variables are selected and their predictive models are constructed by partial least square (PLS) method. The Euclidean norms of parameters of PLS models are estimated and a fault diagnosis can be performed as comparing with parameters of PLS models based on normal operational conditions. To improve the monitoring performance, cumulative summation (CUSUM) control chart is employed and the changes of model parameters are recorded to identify the type of an unknown fault. To verify the efficacy of the proposed model, Tennessee Eastman (TE) process is tested and this model can be easily applied to other complex processes.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.473-484
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• 2021

This study aims to examine the role of training and absorptive capacity as a mediator to examine the impact of human capital dimensions on the performance of an organization. This study employs the quantitative approach for analysis. A sample of 208 respondents was collected from the textile factories based in Karachi and Faisalabad. Data was analyzed using the PLS-SEM technique. PLS-SEM algorithm was used to check the validity and reliability of the data. PLS-SEM bootstrapping was used for studying the impact. The results show that the skills have an insignificant impact on organizational performance. Education and skills have an insignificant indirect impact on the performance of an organization. The research findings show that the human capital dimensions are full and partially mediated via absorptive capacity and training. The findings revealed that if we implement one by one dimension of human capital then it will not cause any increase in the organization's performance but if we implement all dimensions then it results in optimal performance. Thus, this study suggests adopting effective training techniques and creating absorptive capacity in an organization to increase the performance of an organization. The findings of this study significantly contribute to the existing body of knowledge.