• Journal of the Chungcheong Mathematical Society
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• v.8 no.1
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• pp.1-10
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• 1995

For analyzing systems of multi-variate nonlinear equations, the linearized modelling techniques are elaborated. The technique applies Newton-Raphson iteration, partial differentiation and matrix operation providing solvable solutions to complicated problems. Practical application examples are given in; determining the zero point of functions, determining maximum (or minimum) point of functions, nonlinear regression analysis, and solving complex co-efficient polynomials. Merits and demerits of linearized modelling techniques are also discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.133-136
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• 2005

Compressive strength of recycled aggregate concrete was tested by the core and by the non-destructive testing. A prediction model of compressive strength considering the replacement level of recycled aggregate was suggested by multi-regression analysis and was compared with test results. Also, Test results showed that the ratio of compressive strength by core and non-destructive testing to actual was somewhat affected by the replacement level of recycled aggregate.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.35-47
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• 2023

Purpose : As the population aging deepens, the number of elderly people with arthritis is also continuously increasing. Accordingly, this study intended to identify the factors influencing the health-related quality of life (HINT-8) of the elderly with arthritis according to household type and provide baseline data for developing a measure to enhance the life quality of the elderly with arthritis. Methods : The factors influencing the health-related quality of life (HINT-8) of the elderly with arthritis were identified based on the raw data from the Korea national health and nutrition examination survey conducted in 2021. Data were analyzed with SPSS Statistics ver 25.0 for windows (IBM Corp), and the significance level (α) was set to .05. Statistical analysis was performed with t-test, ANOVA, multiple regression analysis, and post-hoc analysis with Duncan test. Results : The factors that influenced the health-related quality of life (HINT-8) of single-households were medical aid (β=-.17, p=.045), restriction of activity (β=-.17, p=.023), self-rated health status (β=.29, p<.001), and anxiety scale (β=-.36, p<.001). The factors that influenced the health-related quality of life (HINT-8) of multi-households were an age of 75 or over (β=-.14, p=.011), living in rural (β=-.14, p=.003), the outpatient department treatment experience (β=-.09, p=.047), self-rated health status (β=.26, p<.001), anxiety scale (β=-.29, p<.001), and stress (β=-.22, p<.001). Conclusion : Factors affecting the health-related quality of life (HINT-8) of the elderly with arthritis were found to be different between single-person households and multi-person household. Therefore, it is necessary to prepare measures to improve the quality of life of the elderly with arthritis by considering the factors influencing the health-related quality of life (HINT-8) of the elderly with arthritis according to the household type identified in this study.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.3039-3056
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• 2020

Beaches have many risk factors that cause various accidents, such as drifting and drowning, these accidents have many risk factors. To analyze them, in this paper, we identify beach risk factors, and define the criteria and correlation for each risk factor. Then, we generate new risk factors based on Fuzzy theory, and define Situation Awareness for each time. Finally, we propose a beach risk assessment and prediction model based on linear regression using the calculated risk result and pre-defined risk factors. We use national public data of the Korea Meteorological Administration (KMA), and the Korea Hydrographic and Oceanographic Agency (KHOA). The results of the experiment showed the prediction accuracy of beach risk to be 0.90%, and the prediction accuracy of drifting and drowning accidents to be 0.89% and 0.86%, respectively. Also, through factor correlation analysis and risk factor assessment, the influence of each of the factors on beach risk can be confirmed. In conclusion, we confirmed that our proposed model can assess and predict beach risks.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.208-213
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• 2001

Objective of this paper is to develop a new approach involving the use of an Artificial Neural Network(ANN) and multiple regression methods in the prediction of process parameters on bead height for GMA welding process. Using a series of robotic are welding, multi-pass butt welds carried out in order to verify the performance of the neural network estimator and multiple regression methods. To verify the developed system, the design parameters of the neural network estimator are selected from an estimation error analysis. The experimental results show that the proposed models can predict the bead height with reasonable accuracy and guarantee the uniform weld quality.

• Journal of Biosystems Engineering
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• v.23 no.2
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• pp.105-114
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• 1998

Granule application with a boom has merits of accurate application and high field efficiency. In order to develop a boom granule applicator, aerodynamic properties of agrichemicals should be investigated. This study was accomplished to investigate aerodynamic properties of granules and factors affecting on them. The tested agrichemicals were urea, compound fertilizer (17-21-17), sand and zeolite. Basic physical properties of granules such as true density, sphericity, and arithmetic mean diameter for those materials were analyzed. Regression equations for pickup velocity (v$_{p}$) and saltation velocity (v$_{s}$) were proposed by the data transformation and the multi-regression analysis as follows : (equation omitted) where, 0< s < 1, 0< λ$_{i}$< 3, 35 < D/d$_{p}$ < 350, 1000 $_{p}$/p$_{a}$ < 2500 The range of pickup velocity of fertilizers and other agrichemicals were shown to be 10-16m/s and 9-13m/s, respectively. The saltation velocity of fertilizer and other agrichemicals were 3 m/s and 4 m/s, respectively.y.ively.y.y.

• Journal of the Korean Home Economics Association
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• v.49 no.5
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• pp.71-80
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• 2011

The purpose of this study was to investigate the mediating effects of anger expression on the relationship between child abuse experience and the method of resolving interpersonal conflicts. For the study, 3,050 4th to 6th grade children from Kyunggi-do were sampled. The collected data were analyzed using simple regression, multi regression and a path analysis. This study showed that child abuse experience influenced the method of resolving the interpersonal conflicts via the expression of anger. In other words, anger expression could function as a pathway between child abuse experience and the method of resolving interpersonal conflicts.

• International Journal of Control, Automation, and Systems
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• v.6 no.5
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• pp.639-650
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• 2008

Electricity price forecasting has become an integral part of power system operation and control. In this paper, a wavelet transform (WT) based neural network (NN) model to forecast price profile in a deregulated electricity market has been presented. The historical price data has been decomposed into wavelet domain constitutive sub series using WT and then combined with the other time domain variables to form the set of input variables for the proposed forecasting model. The behavior of the wavelet domain constitutive series has been studied based on statistical analysis. It has been observed that forecasting accuracy can be improved by the use of WT in a forecasting model. Multi-scale analysis from one to seven levels of decomposition has been performed and the empirical evidence suggests that accuracy improvement is highest at third level of decomposition. Forecasting performance of the proposed model has been compared with (i) a heuristic technique, (ii) a simulation model used by Ontario's Independent Electricity System Operator (IESO), (iii) a Multiple Linear Regression (MLR) model, (iv) NN model, (v) Auto Regressive Integrated Moving Average (ARIMA) model, (vi) Dynamic Regression (DR) model, and (vii) Transfer Function (TF) model. Forecasting results show that the performance of the proposed WT based NN model is satisfactory and it can be used by the participants to respond properly as it predicts price before closing of window for submission of initial bids.

• Journal of Information Technology Applications and Management
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• v.27 no.3
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• pp.37-54
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• 2020

In response to the recent decline in the school-age population, universities have made attracting foreign students a major policy task for universities. As a result, the number of foreign students increased rapidly in terms of quantity, but in terms of quality, the risk is inevitable. Accordingly, the government presented education and internationalization competency certification system indicators on the basis of which quality control of students was systematized. Based on the above certification system, this study focused on analyzing the multiple factors that are actually given to the academic adaptation (performance) of the 2200 students who entered a certain university. In addition, factors other than the certification system index were discovered to comprehensively track how they affect the academic performance of students studying abroad. The researcher found the multi-reciprocal model analysis showed that the difference between the learner and the moderator was significant, and whether or not they had the Korean proficiency test (TOPIK) was significant. It also said that it could have a direct impact on Chinese University Entrance Exams (高考) are significant. If a model that is very effective in selecting students is established by each university and used as an indicator through this study, it will serve as a basis for efficient selection of students.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.443-449
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• 2014

Although risk reduction of construction projects have been continued, the risk of fatal accident has been increased. The purpose of this paper is to reduce the cause of the essential risk factors. Questionnaire survey of construction companies in domestic was conducted and the Multiple Regression Analysis of statistics program was used to grasp effective factors among the risk factors of construction companies in domestic. Development of the essential risk factors and its application to projects could lead to improvements such as compression of network, reduction of cost, improvement of quality and reduction of safety accident.