• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.327-336
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• 2001

This work concerns estimating a regression function, which is not linear, using aggregate data. In much of the empirical research, data are aggregated for various reasons before statistical analysis. In a traditional parametric approach, a linear estimation of the non-linear function with aggregate data can result in unstable estimators of the parameters. More serious consequence is the bias in the estimation of the non-linear function. The approach we employ is the kernel regression smoothing. We describe the conditions when the aggregate data can be used to estimate the regression function efficiently. Numerical examples will illustrate our findings.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.1_2
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• pp.15-34
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• 2006

This paper introduces an empirical modeling technique. This technique uses a set of sample results which are collected from a few small scale simulations. Empirical models are developed by applying a couple of statistical estimation techniques to these samples. We built two types of models for cache miss rates in Symmetric Multiprocessor systems. One is for the changes of input data set size while the specification of target system is fixed. The other is for the changes of the number of processors in target system while the input data set size is fixed. To develop accurate models, we built individual model for every kind of cache misses for each shared data structure in a program. The final model is then obtained by integrating them. Besides, combined use of Least Mean Squares and Robust Estimations enhances the quality of models by minimizing the distortion due to outliers. Empirical modeling technique produces extremely accurate models without analysis on sample data. In addition, since only snail scale simulations are necessary, once a set of samples can be collected, empirical method can be adopted in any research areas. In 17 cases among 24 trials, empirical models present extremely low prediction errors below $1\%$. In the remaining cases, the accuracy is excellent, as well. The models sustain high quality even when the behavioral characteristics of programs are irregular and the number of samples are barely enough.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.8
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• pp.703-710
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• 2012

At the stage of conceptual design of a helicopter, it is a general way using low fidelity analysis methods because of a large number of design calculations and trade-off studies. Determination of empirical parameters used in analysis codes for more practical design, depends on an user's design experiences, which effects on the accuracy and the fidelity of conceptual design results. Thus, more precise and logical method should be required to determine the empirical parameters used in the conceptual design of a helicopter. The present method is to be used not only in verifying the empirical parameters generated by design requirements, but also regenerate them if they contain any errors. Empirical parameters produced by present method were used to design a helicopter with a payload objective and performance constraints of an operating helicopter. As a result, weights and geometries of designed helicopter matched the target value within 5% significance level, proving that the suggested parameter generating method can be useful in the conceptual design of a helicopter.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.2
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• pp.15-27
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• 2023

The purpose of this research is to investigate the impact of Business Intelligence (BI) on the relation between Big Data Analytics (BDA) and Financial Performance (FP), at the beginning we reviewed the academic accounting and finance literature to develop the theoretical framework of business intelligence, big data and financial performance in terms of definition, motivations and theories, then we conduct an empirical analysis based on questionnaire-base survey data collected. The researchers identified the study population in the joint-stock companies listed on the Egyptian Stock Exchange and operating in the sectors and activities related to modern technologies in information systems, big data analytics, and business intelligence, in addition to the auditing offices that review the financial reports of these companies, and The sector closest to the research objective is the communications, media, and information technology sector, where the survey list was distributed among the sample companies with (15) lists for each company, and (15) lists for each audit office, so that the total sample becomes (120) individuals (with a response rate 83.3%), The results show, First, Big data analytics significantly affect organizations' financial performance, second, Business intelligence mediates (partial) the relationship between big data analytics and financial performance.

• Journal of the Korean Society of Costume
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• v.65 no.1
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• pp.30-45
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• 2015

This study summarizes the dissemination aspects of liturgical vestments in Korea, and organizes the value and meanings of these disseminations as it appeared in the history of costumes by carrying out an empirical analysis on the relics of liturgical vestments since the modern times. It also examines its design characteristics as well. Liturgical vestments have symbolic meaning for the purpose and solar term of ceremonial occasions and it also functions as a way to differentiate the position and duty of the clergy. Liturgical vestments developed on the basis of ancient Greek-Roman costumes and transformed each situation and social trend of the age. Korean liturgical vestments started with their traditional costumes, in 1887, it were changed into French(western) style with freedom of religious. After the secondary Vatican Council held in 1962, various regulations were changed to spread the Catholic doctrines and ideology. This study conducted an empirical analysis and design consideration on the 28 relics of modern liturgical vestments on the basis of the foregoing standard and concept. As a result of analysis, relics were investigated as research materials worn by Bishops after 1960s. And design elements are that the relics used materials and ornament of Hanbok with flower patterns and decoration such as letter patterns including 壽(life) 福(luck) 喜(pleasure) as well as Chrysanthemum and Mancaowen design. These transition reflected by amend regulation of Vatican Council II. Accordingly, this data has been confirmed to be important for the history of costumes as it informs what process of changes liturgical vestments spread in Korea went through before they are worn as current appearance.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.497-506
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• 2016

The purpose of this study is to inquire into the relationships between empirical value, emotional response and behavioral response of skin-SCUBA diving participants. This study sampled 300 skin-SCUBA diving participants in the SCUBA diving pool of the Seoul Olympic Stadium, and the SCUBA diving pool of the Suwon World Cup Stadium by using convenience sampling. For data processing, this study conducted frequency analysis, exploratory factor analysis, reliability analysis, correlation analysis and multi-regression analysis using PASW 18.0 Ver. The concrete results are as follows: First, the empirical value of a skin-SCUBA diving participant was found to have a significant influence on emotional responses. Second, the empirical value of a skin-SCUBA diving participant was found to have a significant influence on behavioral responses. Third, the emotional response of a skin-SCUBA diving participant was found to have a significant influence on behavioral responses.

• Industry Promotion Research
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• v.5 no.3
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• pp.45-51
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• 2020

This study analyzed the influence of investment and fostering support on gross regional product by utilizing big data using multiple regression analysis. Gross regional product (GRDP) is an index that intensively contains the production scale, expenditure level, income level, and industrial structure of each region, and is an important data used for regional economic analysis and national policy establishment. In order to properly carry out the country's major national tasks, it is necessary to accurately grasp the regional economy, and as a result, interest in regional gross domestic product is rapidly increasing. In particular, foreign investment has a significant impact on the economy of the host country, and many empirical analyzes are being conducted. In this study, correlation analysis and multiple regression analysis were conducted to examine the influence of foreign investment and domestic development support on gross regional product, and as a result, it was concluded that investment and support as a whole had a positive effect on gross regional product.

• Journal of Korean Society of Transportation
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• v.30 no.2
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• pp.127-136
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• 2012

Multi-car rear-end collision accidents have three categories: sequential collision from the rear which is commonly referred to as chain reaction collision, sequential collision from the front, and mixed-order collision. This paper suggests several effective methods of reconstruction analysis for multi-car rear-end collision accidents. First, by incorporating the traditional empirical method which uses vehicle damage caused by brake dive and passenger injuries, with results of theoretical analysis made within mechanics of rigid body, it is made possible for the method to be put to immediate practical use. A methodology to precisely analyze multi-car rear-end collision accidents was suggested using a simulation program simultaneously with a video event data recorder which is starting to be widely used in domestic vehicles. To go beyond the simple intuitive analysis of the video event data recorder, the simulation analysis based on the results of video analysis was executed to acquire various information, so that the causes and responsibility could be clearly stated.

• Journal of Korea Water Resources Association
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• v.49 no.3
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• pp.197-205
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• 2016

Recently, natural hazards have occurred frequently due to climate change. The research need for predicting variability and tendency of precipitation and temperature has been increased. However, it is difficult to determine the characteristics of precipitation and temperature within a confidence range since they change due to complex factors with choppy and too many components. If their characteristics having more than one component are decomposed, then it can be useful for determining the variation of such characteristics more accurately. In this study, Korean precipitation and temperature were decomposed and their Intrinsic Mode Function (IMF) were extracted from Empirical Mode Decomposition (EMD). Finally, the characteristics of Korean precipitation and temperature data were analyzed in terms of periodicity and tendency.

• Journal of Korea Trade
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• v.27 no.1
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• pp.101-118
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• 2023

Purpose - Korea became a trillion-dollar trading country in 2011. With the exponential increase in Korea's trade volume over the past decades, trade-related administrative burdens per capita for Korea Customs became enormous, for which the government established the Single Window, a trade-facilitating system, in 2004 to enhance the efficiency of customs-clearing procedures for traders. This paper focuses on finding whether the Korean Single Window system affects the country's trade facilitation positively through an empirical methodology. Design/methodology - To find empirical evidence that Single Window affects trade facilitation for the customs-clearing procedure, this study assumes that a time-efficient environment enables the handling of the increase in trade volume, under which four independent variables related to import customs-clearing procedures and two dependent variables to import were adopted for empirical analysis. The import customs procedures are classified into four steps from port entry to declaration acceptance. To understand the relationship between variables, scattered plots and correlation coefficients were calculated. Eight hypotheses were set and underwent simple linear regression. The data for analysis were collected by Korea Customs, and were about the lead time of import, the volume of imports in million USD, and the number of import declarations reported to customs offices on a monthly basis from 2005 to 2013. Findings - Six of the eight hypotheses showed the statistically significant result that lead time in the import customs-clearing procedure positively affects the number of import declaration reports and import volume. Specifically, Hypothesis 1, Hypothesis 2, and Hypothesis 3 strongly support the assumption lead time in import customs declaration has an inverse relationship with the number of import declarations, which means that the shorter the import lead time, the more import declaration increases. Research Limitations/Implications - With limited data accessibility to the government's custom-sclearing procedures, only the import lead time for customs clearance were adopted as independent variables. This paper, however, successfully found that the Single Window system contributed to trade facilitation. Originality/value - This study found that the time-saving Single Window system of Korea Customs enables itself to manage an exponentially-increasing trade volume by creating a trade-facilitating environment for customs personnel and traders, which may be a unique implication found through quantitative methodology.