• Journal of Satellite, Information and Communications
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• v.3 no.1
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• pp.15-21
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• 2008

The high peak to average power ratio (PAPR) of OFDM (Orthogonal Frequency Division Multiplexing) system introduces inevitable non-linear distortion in the transmission due to the amplifier non-linear property. This causes both in-band distortion and out of band spectrum re-growth. In this paper we tried to compensate the problem by using polynomial based pre-distortion. Estimation of both the non-linear and inverse non-linear polynomial is achieved using the Least Square Error (LSE) method. Using these parameters closed form pre-distorter can be easily created. We also used the 'partial peak cancellation and clipping' method to remove the high peak present in the non constant amplitude of the OFDM signal responsible to drive the amplifier in near saturation region for better performance of the system

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.715-722
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• 2016

Rapid determination of food quality is important in food distribution. In this study, the chemical properties of oats were analyzed using visible-near infrared (VIS-NIR) spectroscopy. The objective of this study was to develop and validate a predictive model of oat quality by VIS-NIR spectroscopy. A total of 200 oat samples were collected from domestic and import markets. Reflectance spectra, moisture, protein, fat, Fe, and K of oat samples were measured. Reflectance spectra were measured in the wavelength range of 400 - 2,500 nm at 2 nm intervals. The reflectance spectrum of an oat sample was measured after sample cell and reflectance plate spectrum measurement. Preprocessing methods such as normalization and $1^{st}$ and $2^{nd}$ derivations were used to minimize the spectroscopic noise. The partial-least-square (PLS) models were developed to predict chemical properties of oats using a commercial software package, Unscrambler. The PLS models showed the possibility to predict moisture, protein, and fat content of oat samples. The coefficient of determination ($R^2$) of moisture, protein, and fat was greater than 0.89. However, it was hard to predict Fe and K concentrations due to their low concentrations in the oat samples. The coefficient of determinations of Fe and K were 0.57 and 0.77, respectively. In future studies, the stability and practicability of these models should be improved by using a high accuracy spectrophotometer and by performing calibrations with a wider range of oat chemicals.

• Journal of Digital Convergence
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• v.13 no.10
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• pp.295-303
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• 2015

This paper is empirically to examine the effects of project manager's competencies (intellectual, managerial, and emotional competencies) on the performance for planning and outcome of NPD (new product development) project in project matrix organization. To achieve this purpose, we employ a field survey of project managers in project matrix organization and PLS (partial least square) structural equation modelling to test hypotheses of our research model. The results show that intellectual competency positively affect both of performances for planning and for outcome, whereas managerial and emotional competencies have not significant effect on them. Our attempt is to provide theoretical implications to current studies related to project management and helps for practitioners to develop a program for selecting and training capable and promising project managers.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.513-525
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• 2020

Purpose: The purpose of this study is to analyze the characteristics of local factors affecting number of tuberculosis death by urban and rural areas. Method: The Partial Least Square(PLS) Regression analysis was used to solve the problem of multicollinearity and number of samples. Result: As a result of analysis, The number of tuberculosis deaths in urban and rural areas is about three times as large. As a result of analysis about Regional Characteristics Factor, In general, children, elderly people, and economically vulnerable populations are more likely to be exposed to tuberculosis. In differential results, it shows that environmental factors such as ultrafine dust and sulfur dioxide have a significant impact on the number of tuberculosis deaths in urban areas and social factors such as depression experience rate in rural areas. Conclusion: The Tuberculosis prevention and management policies that reflect the characteristics of urban and rural areas are needed in the future.

• Journal of Information Management
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• v.42 no.2
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• pp.67-84
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• 2011

In this paper, our goal is to examine the factors of service quality and user's satisfaction in Software as a Service(SaaS). Based on the theoretical framework like service quality theory we develop and test a theoretical model, propose hypotheses and analyze the effects of SaaS' flexibility and customizability on the service quality and the satisfaction of SaaS' users. For this research, questionnaire survey was conducted with literature study and the PLS(Partial Least Square) was used to analyze the measurement model and hypotheses testing. The PLS analysis results indicate that SaaS' flexibility affects SaaS' service quality and the users' satisfaction and SaaS users' satisfaction is influenced by SaaS' service quality. Furthermore, SaaS' customizability affects SaaS' service quality, however, does not affect the users' satisfaction. Practical implications of these findings and future research implications are also discussed.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.197-205
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• 2020

The present study analyzed the effector that has an influence on continuance intention to use YouTube that is a prime platform to distribute visual contents. Whether the dispersion of information communication technology succeeds or not is determined by a more extent which user uses active and continued than adopts fast. From this point of view, we employed partial least square(PLS) path modeling to analyze structural causality among constructs in the post-adoption model(PAM). As a result, all paths given in PAM except for the path 'confirmation-satisfaction' were validated. Especially, confirmation mediated with satisfaction than perceived usefulness has a more effect on continuance intention. Finally, we described the limitation of the present study and the suggestion for future research.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.4
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• pp.915-920
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• 2015

The commitment of top management is still insufficient for information security even the core of information security governance is dependent on the leadership of top management. In this situation, information security committee can be a good way to vitalize the commitment of top management and its activities are essential for implementing information security governance. The purpose of this study is to test that information security committee affects implementing information security governance and security effect. For a empirical analysis, questionnaire survey was conducted and the PLS(Partial Least Square) was used to analyze the measurement and structural model. The study result shows that a hypothesis related value delivery is not accepted and it is required to study various methods about how the information security provides positive value to business.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.2
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• pp.449-461
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• 2016

If students are not aware of the information security, they easily let others know their information or they use others' information with no sense of guilt. The information security education is necessary to protect and prevent students from cyber crime. However, South Korea's information curriculum has no specific information security education course and it has led a school or teacher to teach contents of information ethics superficially. The purpose of this paper is to find the factors affecting the information security practice of the elementary school students. For an empirical analysis, questionnaire survey was conducted and the Partial Least Square(PLS) was used to analyze the research model. The analysis results show that the information ethics awareness and the information security awareness have a positive impact on the information security practice. The results of this study are expected to help choose the specific information security curriculum required for the information security practice of elementary school students.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.4
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• pp.278-283
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• 2001

The overall objective of this research was to show a NIR soil analyzer assessing soil fertility by measuring soil properties rapidly. A total of 140 soil samples were used to obtain calibrations and validation estimating soil properties. The soil samples were ground to pass 0.2mm sieve openings. Partial least square regression analysis was used to develop a calibration for soil analysis. The results indicated that NIR soil analyzer could be used as a routine method for quantitatively determining pH, OM, total nitrogen, CEC, extractable Ca, Mg, K, available $SiO_2$ and soil moisture simultaneously within one minute. Therefore, the NIR soil analyzer may be suitable for quick estimation of soil fertility estimation in fertilizer assessments.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.4
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• pp.273-277
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• 2001

Traditional methods of chemical analysis for the soil properties take time and produce harmful waste. The purpose of this research was to evaluate an NIR technique for measuring some soil properties that are rapid and accurate in soil fertility assessments. The NIR instrument (InfraAlyzer 500, Bran & Luebbe Co.) was used for obtaining spectral data from 140 finely ground soil for calibrations and validation estimating pH, CEC, extractable Ca, Mg, K, $SiO_2$, humic acid and EC. Partial least square regression analysis was used to develop a calibration of NIR spectroscopy method. The results indicated that NIR spectroscopy could be used as a routine nondestructive method quantitatively determining soil chemical properties quickly. However the NIR technique may require sample preparation to obtain even diffuse reflection spectra from the soil and data manipulations to obtain optimal predictions.