• Journal of Korean Society of Transportation
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• v.27 no.2
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• pp.23-34
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• 2009

This paper is described as an experimental analysis for the probabilistic directional design hour volume estimation. The main objective of this paper is to derive acceptable design rankings, PK factors, and PD factors. In order to determine an appropriate distribution for acceptable design rankings, 12 probability distribution functions were employed. The parameters were estimated based on the method of maximum likelihood. The goodness of fit test was performed with a Kolmogorov-Smirnov test. The Beta General distribution among the probability distributions was selected as an appropriate model for 2 lane roadways. On the other hand, the Weibull distribution is superior for 4 lanes. The method of the inverse cumulative distribution function came up with an acceptable design ranking of design for LOS D. An acceptable design ranking of 2 lanes is 190, while an acceptable design ranking for 4 lanes is 164. The PK factor and PD factor of 2 lanes was elicited for 0.119 (0.100-0.139) and 0.568 (0.545-0.590), respectively. On the other hand, the PK factor and PD factor for 4 lanes was elicited as 0.106 (0.097-0.114) and 0.571 (0.544-0.598), respectively.

• Korean Journal of Social Welfare
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• v.69 no.1
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• pp.223-254
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• 2017

This study was carried out to examine whether the moderated mediating effect of SNS addiction resulting from marital dissatisfaction and loneliness is influenced by gender or size and composition of social capital. 714 married men and women in their 20's to 40's were participated in this study. The data were collected by online research center with quota sampling based on demographical proportion. To analyze this research model, the moderated mediating effect utilizing structural equation was used. The results of this study were summarized as follows. First, it is verified that the loneliness moderated between marital dissatisfaction and SNS addiction. Since the relationship between independent and dependent variable is insignificant, comparison of competition model was able to determine if mediating effect was fully or partially shown. As a result, the complete mediated model was ultimately chosen because its various goodness-of-fit index including $x^2$ performed fairly well. Second, the mediating effect which moderates social capital size was presented in the mediated model between the marital dissatisfaction, loneliness and SNS addiction. Specifically, It implies that group who recognizes their social capital big recognizes the route and effect size more than that who considers their social capital small. And the moderated mediating effect depending on different type of social capital among the marital dissatisfaction and loneliness and between SNS addiction was substantiated. It implies that disequilibration of SNS social capital in face-to-face sphere and in online acted as a danger fact with respect to the marital dissatisfaction, loneliness and SNS addiction. The implications of these findings were discussed, and directions for future studies were also proposed.

• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.1-13
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• 1992

This study was attemped to provide some fundamental data for the safety structural design of biological production facility. Wind speed and snow depth according to recurrence intervals for design load estimation were calculated by frequency analysis using the weather data of 60 stations in Korea. The following results were obtained : 1. Type-I extremal distribution was selected for the probability density function of yearly maximum wind speed and snow depth and result of Chi-square goodness of fit showed highly significance at most regions. 2. Design frequency factors for given number of samples and recurrence intervals were calculated, and also design wind speed and snow depth as shown in Table 5-Table 6 and Fig.3-Fig.4 were derived. 3. About 46.4% of the winds having maximum wind speed at every station was analyzed to be same direction, and the consideration of this fact may improve the structural safety. 4. Considering wind speed and snow depth, protected cultivation is very difficult in Ullungdo and the Youngdong districts, and strong structural design is needed in the Chungnam and Junbuk west seaside against snow depth and the west-south seaside against wind speed in Korea.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.312-316
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• 2012

This study was to present the proper probability distribution models that based on the data for surveys of food cold storage temperatures as the input variables to the further MRA (Microbial risk assessment). The temperature was measured by directly visiting 7 food plants. The overall mean temperature for food cold storages in the survey was $2.55{\pm}3.55^{\circ}C$, with 2.5% of above $10^{\circ}C$, $-3.2^{\circ}C$ and $14.9^{\circ}C$ as a minimum and maximum. Temperature distributions by space-locations was $0.80{\pm}1.69^{\circ}C$, $0.59{\pm}1.68^{\circ}C$, and $0.65{\pm}1.46^{\circ}C$ as an upper (2.4~4 m), middle (1.5~2.4 m), and lower (0.7~1.5 m), respectively. Probability distributions were also created using @RISK program based on the measured temperature data. Statistical ranking was determined by the goodness of fit (GOF) to determine the proper probability distribution model. This result showed that the LogLogistic (-4.189, 5.9098, 3.2565) distribution models was found to be the most appropriate for relative MRA conduction.

• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.797-810
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• 2017

The Korean peninsula is exposed to typhoons every year. Typhoons cause huge socioeconomic damage because tropical cyclones tend to occur with strong winds and heavy precipitation. In order to understand the complex dependence structure between strong winds and heavy precipitation, the copula links a set of univariate distributions to a multivariate distribution and has been actively studied in the field of hydrology. In this study, we carried out analysis using data of wind speed and precipitation collected from the weather stations in Busan and Jeju. Log-Normal, Gamma, and Weibull distributions were considered to explain marginal distributions of the copula. Kolmogorov-Smirnov, Cramer-von-Mises, and Anderson-Darling test statistics were employed for testing the goodness-of-fit of marginal distribution. Observed pseudo data were calculated through inverse transformation method for establishing the copula. Elliptical, archimedean, and extreme copula were considered to explain the dependence structure between strong winds and heavy precipitation. In selecting the best copula, we employed the Cramer-von-Mises test and cross-validation. In Busan, precipitation according to average wind speed followed t copula and precipitation just as maximum wind speed adopted Clayton copula. In Jeju, precipitation according to maximum wind speed complied Normal copula and average wind speed as stated in precipitation followed Frank copula and maximum wind speed according to precipitation observed Husler-Reiss copula.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.35-48
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• 2021

This study is an attempt to establish a model and identify the relationship between the individual characteristics of college students, Internet usage characteristics, exposure to pornography, and anti-social sexual perception. The subjects of the study were 360 college students aged 18 or older in B city, and the collected data were analyzed using the IBM SPSS 21.0 and AMOS 22.0 programs. The goodness-of-fit index of the modified model met the acceptance criteria (𝛘²/df=2.786, GFI=.95, AGFI=.92, SRMR=.06, RMSEA=.07, NFI=.89, CFI=.93, TLI=.90). According to the results of path analysis, the variables that directly affect anti-social sexual perceptions of college students were personal characteristics and exposure to pornography, and the variable with indirect effect was the Internet usage characteristics. The biggest direct effect on anti-social sexual perception was exposure to pornography, and it was confirmed that exposure to pornography was directly affected by personal characteristics and Internet usage characteristics. Therefore, in order to reduce anti-social sexual perceptions among college students, measures should be taken to control personal characteristics and Internet usage characteristics that directly affect the level of exposure to pornography.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1119-1130
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• 2021

Urban flooding caused by localized heavy rainfall with unstable climate is constantly occurring, but a system that can predict spatial flood information with weather forecast has not been prepared yet. The worst flood situation in urban area can be occurred with difficulties of structural measures such as river levees, discharge capacity of urban sewage, storage basin of storm water, and pump facilities. However, identifying in advance the spatial flood information can have a decisive effect on minimizing flood damage. Therefore, this study presents a methodology that can predict the urban flood map in real-time by using rainfall data of the Korea Meteorological Administration (KMA), the results of two-dimensional flood analysis and random forest (RF) regression model. The Ujeong district in Ulsan metropolitan city, which the flood is frequently occurred, was selected for the study area. The RF regression model predicted the flood map corresponding to the 50 mm, 80 mm, and 110 mm rainfall events with 6-hours duration. And, the predicted results showed 63%, 80%, and 67% goodness of fit compared to the results of two-dimensional flood analysis model. It is judged that the suggested results of this study can be utilized as basic data for evacuation and response to urban flooding that occurs suddenly.

• 한국체육학회지인문사회과학편
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• v.54 no.2
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• pp.299-312
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• 2015

The purpose of this study was to find the effects of user experience on flow and satisfaction of electronic hogu system in the taekwondo game. The subjects were players who had experience using electronic hogu system in the taekwondo game for 2014 year 7month~10month. 652 samples out of 750 samples through convenient sampling method were adopted as a final data. We confirmed the goodness of fit test of the model, utilizing SPSS WIN Ver 18.0, and AMOS 7.0, and after which we tested each hypothesis. The results were as follows; First, sentient, emotional, cognitive, behavioral, relational experience of user experience did not have a significant influence on cognition flow. Second, sentient, emotional, relational experience of user experience did not have a significant influence on behavioral flow. Third, cognitive, behavioral experience of user experience had a significant influence on behavioral flow. Fourth, cognition, behavioral flow had a significant influence on satisfaction. Fifth, factor between native and foreigner taekwondo players had significantly different. This paper is a meaningful to figure out user satisfaction of electronic hogu system in taekwondo games and maximize athletic performance.

• Journal of Digital Convergence
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• v.16 no.9
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• pp.147-157
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• 2018

Since Google launched a prediction service for influenza-like illness(ILI), studies on ILI prediction based on web search data have proliferated worldwide. In this regard, this study aims to build short-term predictive models for ILI in Korea using ILI and web search data and measure the performance of the said models. In these proposed ILI predictive models specific to Korea, ILI surveillance data of Korea CDC and Korean web search data of Google and Naver were used along with the ARIMA model. Model 1 used only ILI data. Models 2 and 3 added Google and Naver search data to the data of Model 1, respectively. Model 4 included a common query used in Models 2 and 3 in addition to the data used in Model 1. In the training period, the goodness of fit of all predictive models was higher than 95% ($R^2$). In predictive periods 1 and 2, Model 1 yielded the best predictions (99.98% and 96.94%, respectively). Models 3(a), 4(b), and 4(c) achieved stable predictability higher than 90% in all predictive periods, but their performances were not better than that of Model 1. The proposed models that yielded accurate and stable predictions can be applied to early warning systems for the influenza pandemic in Korea, with supplementary studies on improving their performance.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.137-144
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• 2008

It is important to know pedestrian volume to carry out pedestrian safety analysis and pedestrian friendly design. However, it is too difficult to come across research work related to pedestrian volume analysis in the field of transport, due to lack of interests on pedestrian movement. Most transport research has been focused on vehicles and highways rather than pedestrian. On the other hand, in the field of urban studies, there comes an effective tool to estimate pedestrian volumes using Space Syntax theory. This theory twins out to be effective and economic because it only requires network information, which is easy to acquire from maps and field survey. However, this method is different in the way representing networks from the way that is common in the field of transport. To make up for this point, this paper develops a novel measure for estimating pedestrian volume using Dial's algorithm, and applies the model in the two test networks; Insadong and Soongryemoon networks. The application results reveals that developed measure is an effective tool to explain pedestrian volume; a correlation coefficient between the measure and pedestrian volume is 0.713 in Insadong and 0.492 in Soongryemoon, and the goodness of fit($R^2$) of regression models are 0.893 in Insadong and 0.671 in Soongryemoon. This estimation method is significantly less complicated to estimate the effect of a pedestrian network change than Space Syntax theory, which requires special softwares not readily available.