• Journal of Korean Society of Steel Construction
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• v.20 no.2
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• pp.237-246
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• 2008

The cross-sections of continuous multi-span beams sometimes suddenly increase, or become stepped, at the interior supports of continuous beams to resist high negative moments. The three-dimensional finite-element program ABAQUS (2006) was used to analytically investigate the inelastic lateral-torsional buckling behavior of stepped beams subjected to pure bending moment and resulted in the development of design equations. The flanges of the smaller cross-section were fixed at 30.48 by 2.54 cm, whereas the width and/or thickness of the flanges of the larger cross-section varied. The web thickness and height of beam was kept at 1.65 cm and 88.9 cm, respectively. The ratios of the flange thickness, flange width, and stepped length of beams are considered analytical parameters. Two groups of 27 cases and 35 cases, respectively, were analyzed for double and single stepped beams. The combined effects of residual stresses and geometrical imperfection on inelastic lateral-torsional buckling of beams are considered. First, the distributions of residual stress of the cross-section is same as shown in Pi, etc (1995), and the initial geometric imperfection of the beam is set by central displacement equal to 0.1% of the unbraced length of beam. The new proposed equations definitely improve current design methods for the inelastic LTB problem and increase efficiency in building and bridge design. The proposed solutions can be easily used to develop new design equation for inelastic LTB resistance of stepped beams subjected to general loading condition such as a concentrated load, a series of concentrated loads or uniformly distributed load.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.319-327
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• 2016

The objective of this study is to identify the secular trend in age at menarche and to investigate the factors influence the early menarche(<12 years old) among Korean middle and high school girls. We analyzed data from the Korean Youth Risk Behavior Web-based Survey(KYRBWS) 2006-2014. This study was a descriptive study of 216,917 Korean middle and high school girls born between 1988 and 2002. Linear trends test performed to assess the trend age at menarche and percentage of early menarche. Multiple logistic regression analysis was to assess the risk factors influence the early menarche. Mean age at menarche decreased from $12.61{\pm}1.32$ years for middle and high school girls born 1988 to $11.88{\pm}0.75$ years for those born 2002(p for trends<.001). Percentage of early menarche increased from 19.7% to 25.2% between 1988 and 2002(p for trends<.001). Living in city, higher stress level, short sleep duration, and higher body mass index were associated with an early menarche among middle and high school girls(all p<.001). We found that age at menarche is still falling in the Korean adolescents, and it need intervention strategies to control the early menarche.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.6
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• pp.237-247
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• 2008

A virtual screening is the process of reducing an unmanageable number of compounds to a limited number of compounds for the target of interest by means of computational techniques such as molecular docking. And it is one of a large-scale scientific application that requires large computing power and data storage capability. Previous applications or softwares for molecular docking such as AutoDock, FlexX, Glide, DOCK, LigandFit, ViSION were developed to be run on a supercomputer, a workstation, or a cluster-computer. However the virtual screening using a supercomputer has a problem that a supercomputer is very expensive and the virtual screening using a workstation or a cluster-computer requires a long execution time. Thus we propose a service-based virtual screening system using Grid computing technology which supports a large data intensive operation. We constructed 3-dimensional chemical molecular database for virtual screening. And we designed a resource broker and a data broker for supporting efficient molecular docking service and proposed various services for virtual screening. We implemented service based virtual screening system with DOCK 5.0 and Globus 3.2 toolkit. Our system can reduce a timeline and cost of drug or new material design.

• Journal of the Korean Society of Food Culture
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• v.29 no.6
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• pp.648-658
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• 2014

The aim of this study was to investigate the relationships between eating habits and health among adolescents in Shanghai and Heze, China. A cross-sectional study was conducted in 2013 on 2,089 adolescents; 1,089 students were from Shanghai and 999 students from Heze region. Eating habits, weight, height, and nutritional knowledge were assessed using a self-administered questionnaire. Eating habits score was classified into two categories: healthy eating habits and unhealthy eating habits, based on "Korean Youth Risk Behavior Web-based Survey", for statistical data analysis. Associations between eating habits, BMI, and nutritional knowledge were examined using a general linear model with adjustment of potential confounding factors such as region, gender, age, parents' education level, and pocket money. Statistical analyses were performed using the SAS (version 9.3) program. Proportions of healthy eating habits group were 90.0% for breakfast (3-7 times/wk), 29.1% for fruit (${\geq}once/d$), 12.5% for vegetable (${\geq}3times/d$), 7.3% for milk (${\geq}2times/d$), 90.0% for fast food (<3 times/wk) consumption, respectively. The average BMI score was 20.1 (Shanghai 20.5 Heze 19.6), which is in the range of normal weight. Rates of obesity and overweight were 16.5% and 8.3% in Shanghai and Heze, respectively. There were significant negative correlations between intake frequencies of breakfast, fast food, biscuits, sugar, chocolate, and BMI score. Eating habits and nutritional knowledge score showed a significant positive correlation. These results showed better eating habits regarding eating regularity and consumption of fruits and soft drinks in Chinese adolescents compared with Korean adolescents, although cultural differences were not fully considered. This study demonstrated significant associations of BMI and nutritional knowledge with dietary behavior in Chinese adolescents in two regions of China. Further studies on Chinese adolescents from other regions in China should be considered.

• Informatization Policy
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• v.24 no.4
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• pp.3-16
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• 2017

With the development of social media services in the era of Web 2.0, the public opinion formation site has been partially shifted from the traditional mass media to social media. This phenomenon is continuing to expand, and public opinions on government polices created and shared on social media are attracting more attention. It is particularly important to grasp public opinions in policy formulation because setting up educational policies involves a variety of stakeholders and conflicts. The purpose of this study is to explore public opinions about education-related policies through an empirical analysis of social media documents on education policies using opinion mining techniques. For this purpose, we collected the education policy-related documents by keyword, which were produced by users through the social media service, tokenized and extracted sentimental qualities of the documents, and scored the qualities using sentiment dictionaries to find out public preferences for specific education policies. As a result, a lot of negative public opinions were found regarding the smart education policies that use the keywords of digital textbooks and e-learning; while the software education policies using coding education and computer thinking as the keywords had more positive opinions. In addition, the general policies having the keywords of free school terms and creative personality education showed more negative public opinions. As much as 20% of the documents were unable to extract sentiments from, signifying that there are still a certain share of blog posts or tweets that do not reflect the writers' opinions.

• International Commerce and Information Review
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• v.15 no.4
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• pp.391-418
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• 2013

The development of web 2.0 technologies created the popularization of social media. People use social media for information communication with many purposes. Under such an environment, this paper examines the acceptance of word-of-mouth information dissemination through social media. The determinants of acceptance and the effect of acceptance on purchase intention as the result of information on social media pertaining to overseas tourism are researched in detail. The consumer choice for international travel involves a decision making with high uncertainty and thus people are using the word of mouth information strongly. Empirical analysis using SPSS, AMOS analysis software was performed on sample data consisting of 385 collected surveys. This paper shows the neutrality of eWOM, the professionalism of senders, and that the practicability of eWOM significantly affects the acceptance of the information. In addition, the acceptance of eWOM information has a significant effect on the spread of eWOM and customers' purchase intention. The paper shows that the practicability of information and the professionalism of word-of-mouth information should be improved.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1075-1078
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• 2015

Three kinds of typical practices to reflect the values of Agile Development Methodology were selected from a previous study. Those were Communicate using Web 2.0 collaboration tools, test-driven development (TDD, Test-Driven Development) method is adopted, and refactoring. In this study, we set up a hypothesis that the adoption of TDD project will make user satisfaction is higher. Select 100 sample projects from SourceForge(sourceforge.net), the most popular open source hosting site, the criteria is we can be determined whether operate in the project (developer least 7 people, bugs can occur more than 100, created the project since 2000). To determine whether the use of automated development tools xUnit of TDD through the CVS and SVN log analysis. Using data from the FLOSSmole and to evaluate the user experience of the project. User satisfaction of each project Rating, bug fix cycle, downloads and pageviews. Through this study, correlates of whether TDD adoption and user satisfaction, we will suggest a reflected the Agile practices new open source development methodology. As a result, it contributes to increase the maturity of the open source community.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6325-6332
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• 2015

Although distortions of horizontally curved box girder are more susceptible than which of the straight girder due to curvature effect, current domestic design standards does not present spacing of intermediate diaphragms for the curved box girder. In this study, parametric studies for straight and curved box girder considering distortional warping normal stresses based on linear finite element analysis were carried out. Single span curved girders were chosen for analysis based on current domestic bridge data with 1-6 of solid intermediate diaphragms, 0-30 degree of subtended angle, 30m and 60m of span length and 2-3m of flange width and web height. The adequate spacing of diaphragms for the box girder were suggested considering subtended angles and bending and distortional warping normal stress ratios with 5%, 10%, 15% and 20%. The analysis results were also compared to a current design standard and suggested spacing of diaphragm were evaluated.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.682-695
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• 2019

In recent years, using a connected platform, companies have built and implemented a mobile viral marketing strategy to attract new customers and to have long-term relationships with existing customers. The emergence of interactive Web 2.0 has led to an explosive increase in customer engagement, and practitioners have become interested in connected platform to build close relationships with their customers. However, the study on the effectiveness of various customer influx methods using the connected platform that companies utilize for an increase of customer participation is insufficient. Based on the theoretical study of Sashi (2012), this study analyzes the actual mobile viral promotion of company A's open market shopping mall for the purpose of bringing new customers and having a long-term relationship with the new customers[1]. By analyzing the customer engagement type, the implications for the effectiveness of mobile viral promotion are suggested. First, as a result of the immediate effect of online viral promotion, promotions are partially effective in attracting new customers. Second, as a result of examining the change of customer engagement type in order to find out the long - term effect of online viral promotion, it was found that in most cases, new customers were not become satisfied customers and, Laggard Effect, which takes time to become a satisfied customer, has been confirmed.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.32 no.4
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• pp.5-24
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• 2021

The purpose of this study was to investigate and analyze the operating conditions of lecture contents in contactless online classes for University students. First, as a result of analyzing the responses of 93 respondents, 93.3% of the respondents took real-time online lectures (47.7%) or recorded video lectures (45.6%). Second, as a result of analyzing the contents used as textbooks, it was found that e-books (materials) and paper books (materials) were used together (36.6%), or e-books or electronic materials (36.6% and 37.6% respectively) were used in both liberal arts (47.3%) and major subjects (39.8%). In addition to textbooks, both major subjects and liberal arts highly used web materials (47.6% and 40.5% respectively) and YouTube materials (33.3% and 48.0% respectively) as external materials. Third, both liberal arts and major subjects used 'electronic files in the form of PPT or text organized and written by instructors' (62.9% and 58.1% respectively), 'internet materials' (16.7% and 19% respectively) and 'paper book or materials' (10.4% and 12.3% respectively) to share lecture contents. For the screen displayed lecture contents, 93.5% of the respondents satisfied in major subjects, and 90.2% of the respondents satisfied in liberal arts. These results suggest developing multimedia-based lecture contents and an evaluation solution capable of real-time exam supervision, developing a task management system capable of AI-based plagiarism search, task guidance, and task evaluation, and institutionalizing a solution to copyright problems for electronicizing lecture materials so that lectures can be given in the ubiquitous environment.