• Korean Journal of Construction Engineering and Management
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• v.24 no.6
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• pp.81-90
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• 2023

Climate change has resulted in increased frequency and intensity of heat waves, which poses a significant threat to the health and safety of construction workers, particularly those engaged in labor-intensive and heat-stress vulnerable working environments. To address this challenge, this study aimed to propose an interpretable machine learning approach for forecasting personal heat strain by considering the cumulative effect of heat exposure as a situational variable, which has not been taken into account in the existing approach. As a result, the proposed model, which incorporated the cumulative working time along with environmental and personal variables, was found to have superior forecast performance and explanatory power. Specifically, the proposed Multi-Layer Perceptron (MLP) model achieved a Mean Absolute Error (MAE) of 0.034 (℃) and an R-squared of 99.3% (0.933). Feature importance analysis revealed that the cumulative working time, as a situational variable, had the most significant impact on personal heat strain. These findings highlight the importance of systematic management of personal heat strain at construction sites by comprehensively considering the cumulative working time as a situational variable as well as environmental and personal variables. This study provided a valuable contribution to the construction industry by offering a reliable and accurate heat strain forecasting model, enhancing the health and safety of construction workers.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.4
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• pp.641-650
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• 2008

In this study, seven models with distinctly different body types were researched and explanatory variables were reviewed. Review was done by using body measurements and the measurements of the appropriate bodice patterns in 1D, 2D, and 3D measurement methods in order to review the pattern making system and the equations for calculating the dimensions of the sleeve caps, which are readily available. Data on human bodies, which can be the criteria for each body part required for the new system for making sleeve cap part, were selected considering conditions such as items with a significantly high contribution rate from the results of regression analysis and the easiness of measurement. As a result of research, an explanatory variable required for the system for making sleeve caps with high general use was extracted. All items with the exception of the waist circumference and upper arm circumference were about the measurement of the form of human bodies, which were newly set in this study. As a result of this study, the equations for calculating the dimensions of each part of the sleeve caps showed distinct differences in comparison to the conventional system of construction.

• Journal of the Korean Society of Food Culture
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• v.12 no.3
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• pp.265-274
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• 1997

This study was conducted in ordor to find the most suitable conditions for producing the Doenjang with optimal odor compound contents. Three sample groups with the different preparing methods -Doenjang that has not gone through the soy sauce separation process (Doenjang A), Doenjang that has gone through the soy sauce separation process; Meju-20% salt water ratio of 1 : 4 (Doenjang B), and that with the ratio of 1.3 : 4 (Doenjang C)- were tested during different ripening periods. Odor compound contents were analyzed through Solvent Extraction Method and Simultaneous Steam Distillation Extraction (SDE). The number of odor compounds was greatest in Doenjang A and during the mid to late stage in each groups. In the sensory evaluation of Doenjang odors, Doenjang A received the highest scores in the categories of overall preferences, while Doenjang C got the lowest scores. Individual odor didn't vary significantly during ripening periods, but the overall odor and taste preference was highest in the samples ripened for 75 to 120 days. Stepwise multiple regression analysis of major odor compounds of Doenjang revealed that benzeneacetaldehyde is the major explanatory variable for offensive odor. Benzeneethanol, 3-methylthio-propanal and 4-methyl-phenol are the explanatory variables for salty odor, nutty odor and rancid odor, respectively. Odor compounds that contribute to the overall odor preference varied from the compounds that affect the taste preference.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.127-135
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• 2009

It is necessary to forecast the amount of the maximum electricity demand for stabilizing the flow of electricity. The time series data was collected from the Korea Energy Research between January 2000 and December 2006. The data showed that they had a strong linear trend and seasonal change. Winters seasonal model, ARMA model were used to examine it. Root mean squared prediction error and mean absolute percentage prediction error were a criteria to select the best model. In addition, a nonstationary generalized extreme value distribution with explanatory variables was fitted to forecast the maximum electricity.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.411-426
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• 2023

Purpose - The purpose of this study was to explore and diagnose the characteristics and behavioural patterns of rural tourists after COVID-19 using decision tree analysis to classify and identify key segmentation groups. Design/methodology/approach - The CHAID algorithm was used as the analysis technique for the decision tree. The explanatory variables used in the analysis of each decision tree model were demographic variables and rural tourism usage behaviour and perception variables, and the target variables were the preferences of rural tourists' activities after COVID-19. From the Rural Tourism 2020 survey data, 614 samples with rural tourism experience were extracted and used in the analysis. Findings - The variables that significantly explained the preference for each type of rural tourism activity after COVID-19 were rural tourism safety perception, repeated visits to the region, rural tourism priority activity, rural tourism accommodation experience, gender, age group, marital status, occupation, and education level. Among them, rural tourism safety perception was the most important explanatory variable in each analysis model. Research implications or Originality - Overall, to promote rural tourism, it is necessary to enhance the safety image of rural tourism, strengthen loyalty programs for repeat visitors, and develop customized products that reflect the preferred trends of rural tourism.

• Journal of Korean Academy of Nursing
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• v.30 no.4
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• pp.836-846
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• 2000

This Meta-Analysis of 18 studies was conducted to determine the magnitude of th relationship between health promotion behavior and each of explanatory variables. The studies were measured using Health Promoting Life Style(HPLP) developed by Walker and others based on Pender's definiton of health promoting behavior. The sample was collected by searching for The Journal of Korean Academy Nursing Society, The Journal of Korean Women's Health Nursing Academic Society,The Journal of Korean Academic Society of Adult Nursing, Journal of Korean Community Nursing, The Journal of Fundamentals of Nursing, The Journal of Korean Nursing Administration Academic Society, The Korean Journal of Child Health Nursing, The Journal of Korean Psychiatric Academic Society, the dissertations for mater degree or doctoral dissertations for the period from 1980 to 1998. The explanatory variables measured more than 2 times in studies were self-efficacy, perceived health status, self-esteem, internal, powerful-others and chance dimensions of health locus of control, perceived benefits, hardiness, wellbeing and clinical demensions of health concepts, and quality of life(life satisfaction). Effect sizes were calculated by unweighted mean r, weighted mean r by sample size and weighted mean r by quality index score after homogeneity test. The mean r effect size indicator range of each predictor variable were as follows; quality of life (0.50- 0.52), self-efficacy (0.46-0.47), hardiness (0.42-0.44), self-esteem(0.41-0.43), health locus of control- internal(0.32-0.34), health locus of control- powerful others (0.25-0.31), perceived health status(0.18-0.19) and clinical dimensions of health concepts (0.16-0.17).

• Journal of Korean Society of Transportation
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• v.32 no.2
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• pp.139-151
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• 2014

This paper analyzes factors affecting rail transit ridership at urban rail stations of the Daegu Metropolitan City in 2011. Rail transit ridership is analyzed by dividing weekdays and weekends in order that their differences may be observed. The data used in this study includes various explanatory variables, such as floor area which was collected from building ledger and GIS cadastral map, number of bus routes(line) possible to transfer from urban rail transit, number of students enrolled in middle and high schools, and universities located in access areas of rail transit. For this study, multiple regression models are estimated including various explanatory variables affecting rail transit ridership of weekdays and weekends. From the study, the number of statistically significant explanatory variables and the relative effect of each variable are shown to be different between weekdays and weekends.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.265-273
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• 2009

A cross-sectional survey was undertaken to identify risk factors and clinical signs associated with parasitic helminth infections of cattle in Mymensignh district of Bangladesh. A nonrandom convenience sampling method was used to select 138 animals from 40 farmers/herds. The eggs per gram of faeces (epg) for nematodes and trematodes were determined by McMaster and Stoll's methods respectively. Animal-level and herd-level data were recorded by means of a questionnaire. Multi-collinearity amongst explanatory variables were assessed using $2{\times}2{\times}\;X^2$ test and one variable in a pair was dropped if $P{\leq}0.05$ formultiple logistic regression models. Association study between outcome and explanatory variables was conducted using classification tree, random forests and multiple logistic regression. A positive epg was considered as infected. Analyses were performed using $STATA^{(R)}$, version 8.0/Intercooled and $R^{(R)}$, Version 2.3.0. Seventy eight percent of the cattle were found to be infected with at least one type of helminth. Twenty four pairs of combinations of explanatory variables showed significant associations. Male animals (OR=3.3, P=.006, 95% CI=1.4, 7.7) were associated with significantly increased prevalence of nematode infection. Female cattle of the study area are mostly cross-breed, kept indoor, fed relatively good diet and not used for draught purpose. Males are used for draught purpose thereby more exposed to nematode infective stage and provided with relatively poor diet. So stressed male cattle may become more susceptible to nematode infection. All of the three statistical techniques selected gender and lumen motility as most important variables in association with nematode infection in cattle. The result of this survey can only be extrapolated to the periurban cattle population of traditional management system.

• Journal of Families and Better Life
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• v.25 no.3 s.87
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• pp.77-87
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• 2007

This study purports to understand the direct and indirect effects between eating disorder behavior of female adolescents and their body-related variables(concerning the degree of diet regime, weight control, body satisfaction, and obesity), self-esteem and internal control, by checking three sub-categorized behavior of eating disorders of diet behavior, bulimia behavior, and eating control behavior. The sample group used for the study consisted of 190 female high school students and 292 female university students; measurement devices used for the study were those of body-related variables, self esteem and internal control, and eating disorder behavior; and data analysis was performed using ${\chi}2$, t-test, Pearson's correlation, regression analysis and path analysis. The results are as follows. First, there is a significant difference between university students and high school students regarding their body satisfaction, weight control experience, and self esteem. University students are more satisfied with their body, have higher self esteem, and control their weight better than high school students. Second, diet behavior shows a correlation with the degree of diet interest, weight control experience, and body satisfaction. Body satisfaction and internal control proved to be correlated with bulimia behavior, while weight control experience, obesity, and self esteem were correlated with eating control behavior. Third, the variables that showed a direct influence on diet behavior as an eating disorder are diet interest, weight control experience, body satisfaction and obesity, in that the explanatory power of the variables is 60.7% with the highest mark on obesity. The variables that showed effects on bulimia are body satisfaction and internal control with an explanatory power of 2.8%. Indirect variables effecting bulimia include objects, diet interest, body satisfaction, and self esteem. The variable with a direct influence on eating control behavior was self esteem with and explanatory power of 4%, whereas the variables of objects, diet interest, body satisfaction, weight control experience, and internal control were all indirectly correlated with eating control behavior.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.743-753
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• 2014

Kim et al. (2006) and Kim et al. (2009) reported a set of explanatory variables affecting donation frequency when they analyzed nationwide survey data on donations collected in 2002 by Volunteer 21, a nonprofit organization in Korea. The primary purpose of this paper is to correct computational errors found in Kim et al. (2006) and Kim et al. (2009), to rectify major results in the Tables and Figures and to supplement Kim et al. (2009) by providing new results. We add two logistic regressions to the ZIP and a mixture of two Poisson regressions of Kim et al. (2009). Through these two logistic regressions we could detect a set of explanatory variables affecting donation activity (0 or 1) and another set of explanatory variables, in which the volunteer (0, 1) variable is common, discriminating the infrequent donor group from the frequent donor group.