• Journal of Korean Society of Transportation
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• v.21 no.4
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• pp.7-16
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• 2003

Objective of this research is to analyze drivers' behaviors at signalized intersection during yellow interval. For this, deceleration rate of stopping, PRT(Perception-Response Time), and the relationship between dilemma zone and deceleration rate of stopping were surveyed at two signalized intersections located at urban area(Songtan and Suwon) and local area(Yongin) As a result, the deceleration rate of stopping at signalized intersections and a range of dilemma zone were estimated. It was found that the deceleration rate of stopping and PRT were 1.6m/sec$^2$ and 1.27sec, respectively. These values are bigger than ITE's values which have been used in our country. Accordingly, it is considered that these values should be used as a new design criteria for the traffic signal control.

• Journal of Internet Computing and Services
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• v.15 no.2
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• pp.59-71
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• 2014

This study applied customer perspective to find out ways how to protect customers' privacy by themselves. It does so by examining the factors which affect customer privacy protection behaviors. Based on the Privacy Act, this study developed the construct of Privacy Rights awareness and finds the law's effect on privacy awareness and behavioral change. The study finds that there exists a significant difference in privacy protection behavior according to privacy rights awareness. Independent variables are as follows: Five variables (Perceived vulnerability, Perceived severity, Perceived response effectiveness, Perceived barriers, Privacy Rights awareness) were tested as critical variables influencing Behavioral Intention in PMT model. Privacy awareness had a moderating effect on the relationship between perceived severity and privacy protection behavior. This study would contribute on theoretical expansion of Protection Motivation Theory and also provide practical implications for effective ways to promote behavioral changes.

• Journal of the Korean Society of Food Culture
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• v.10 no.4
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• pp.327-337
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• 1995

The purposes of this study were to: (a) identify college students' patronage behaviors, (b) develop an instrument measuring the attitudes of University Students towards university foodservices management practices, (c) determine university students' attitude towards the four types of university foodservices, and (d) provide recommendations on marketing strategies for university foodservice. Questionnaires were hand delivered to 600 Yonsei University students by designated coordinators. A total of 549 questionnaires were usable; resulting in an 93.3% response rate. The survey was conducted between November 28 to December 4, 1995. Statistical data analysis was completed using the SAS Programs for descriptive analysis, T-test, ${\chi}^2$ test, ANOVA, Factor Analysis and Stepwise Multiple Regression. Most (88.3%) of students were patronizing university foodservices for lunch. Underground student foodservice (40.1%) and Restaurants outside the campus (33.7%) were primarily used for lunch and dinner respectively. Eighty six percent of university students had 1 to 2 meals per day at university foodservices. The reasons given by students for patronizing university foodservices were as follows: location, time, price, menu, taste. Most of the respondents were least satisfied with hygiene, taste, menu and atmosphere. Data indicated strong support for eight priori dimensions in terms of food, menu, atmosphere, hygiene, employee attitude, facilities and convenience. After the factor analysis, price, fast service and foodservice location attributes were rearranged, combined and created a new dimension called as 'access'. Three dimensions in terms of menu, hygiene, convenience were important to students although performance was perceived as poor through importance-performance analysis. Most of students were not satisfied with all four types of university foodservices. In terms of food quality and price which university foodservices offer, most of respondents were moderately satisfied. According to multiple regression analysis, 93.31% of the variance respondents' satisfaction score could be explained by food, menu, price, atmosphere, hygiene, employee attitude, facilities, and convenience dimensions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.123-130
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• 2010

The aim of this paper is a seismic performance evaluation of metallic damper devices which are efficient in workability and installation process. For this V shape and S shape dampers is considered. The strut figures of dampers are V shape and S shape and, the research parameters are strut height and angle of the dampers. ABAQUS program is used for nonlinear finite element analysis. The analysis is performed with the hysteretic curve that has maximum displacement with 50mm and has increased progressive. As a results of evaluating the yield strength, maximum strength and energy dissipation capacity of each device, V and S shape have a good strength capacity and the devices with strut angle $60^{\circ}$ and strut height 140 and 200mm are evaluated stable in seismic behaviors. The response of S shape is more efficient than that of V shape. In the yield strength estimation process, proposed formula can not estimate the yield strength of V and S shape dampers. Even though, the formula can not consider the variation of strut heights and strut angles. Finally the S shape damper is recommended in seismic performance than V shape damper.

• Journal of the Korean Geotechnical Society
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• v.36 no.6
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• pp.35-46
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• 2020

The input parameters for numerical simulation of the liquefaction phenomenon need to be properly evaluated from laboratory and field tests, which are difficult to be performed in practical situations. In this study, the numerical simulation of the cyclic direct simple shear test was performed to analyze the applicability of Finn and PM4Sand models among the constitutive models for liquefaction simulation. The analysis results showed that the Finn model properly predicted the time when the excess pore water pressure reached the maximum, but failed to simulate the pore pressure response and the stress-strain behavior of post-liquefaction. On the other hand, the PM4Sand model properly simulated those behaviors of the post liquefaction. Finally, the evaluation procedure and the equations of the input parameters in the PM4Sand model were developed to mach the liquefaction cyclic resistance ratio corresponding to design conditions.

• Journal of Radiation Protection and Research
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• v.3 no.1
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• pp.23-28
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• 1978

In order to investigate corelation between contents of dioctylphthalate in polyvinylchloride blent dibutyl tin dilaulate with dibutyl tin maleate as stabilizer and the behaviors of radiation resistance as well as electrical conductivity on irradiated specimens, several observations were carried out. A characteristic peak observed in the range of $1,540-1,640cm^{-1}$ on infrared spectra shows such a sensitive response to radiation as the intensity decreases with increasing doses and that this tendency strongly depressed in the presence of plasticizer. It is seemingly attributed for origin of the peak to the existence of RCOO- ion resulting from dissociation of stabilizere, further the depressive effect of decreasing peak intensity influenced by radiation seems to be caused by resonance absorption in benzen ring being a consistituent of plasticizer. It is also suggestive to be use the peak behavior influenced by radiation as a criterion for the evaluation of radiation resistance of PVC. Further the results obtained from electrical conductivity measurement also exhibit reasonable characteristics explainable with views used for the interpretation of the peak behavior mentioned previousely.

• Korean Journal of Metals and Materials
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• v.50 no.5
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• pp.345-351
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• 2012

A three-point bending test was performed on roll-bonded Mg/Al/STS clad-metal plates under two different testing conditions (Mg layer in tension, or STS in tension) and their mechanical response and fracture behavior were investigated. Bending strength was found to be greater under the condition of Mg layer in tension. Heat treatment at $200^{\circ}C$ increased the bending formability, suggesting the interfacial strength increased at $200^{\circ}C$. Under the condition of Mg in tension, the clad heat-treated at $300^{\circ}C$ and $400^{\circ}C$ fractured in two steps, with the first step associated with the interfacial fracture between Mg and Al, and the second the fracture of the Mg layer. STS/Al layers were found to be bent without complete fracture. Under the condition of STS in tension, the clad heat-treated at $300^{\circ}C$ and $400^{\circ}C$ exhibited a very small load drop at the displacement, which is similar to that of the first load drop associated with the interfacial fracture under the condition of Mg in tension. In this case, no interfacial cracks were found and the complete cut-through fracture of clad was observed at low temperature heat treatment conditions, suggesting excellent interfacial strength. When the heat treatment temperature was higher than $300^{\circ}C$, interfacial cracks were observed. The local stress condition and the position of the interface with respect to the surface were found to have a great influence on the fracture behaviors of clad metals.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.2
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• pp.85-91
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• 2016

The most important factor in the structural design of ships and offshore structures operating in arctic region is ice load, which results from ice-structure interaction during the ice collision process. The mechanical properties of ice related to strength and failure, however, show very complicated aspect varying with temperature, volume fraction of brine, grain size, strain rate and etc. So it is nearly impossible to establish a perfect material model of ice satisfying all the mechanical characteristics completely. Therefore, in general, ice collision analysis was carried out by relatively simple material models considering only specific aspects of mechanical characteristics of ice and it would be the most significant cause of inevitable errors in the analysis. Especially, it is well-known that the most distinctive mechanical property of ice is high dependency on strain rate. Ice shows brittle attribute in higher strain rate while it becomes ductile in lower strain rate range. In this study, the simulation method of ice collision to ship hull using the nonlinear dynamic FE analysis was dealt with. To consider the strain rate effects of ice during ice-structural interaction, strain rate dependent constitutive model in which yield stress and hardening behaviors vary with strain rate was adopted. To reduce the huge amount of computing time, the modeling range of ice and ship structure were restricted to the confined region of interest. Under the various scenario of ice-ship hull collision, the structural behavior of hull panels and failure modes of ice were examined by nonlinear FE analysis technique.

• The Journal of Korean Society for School & Community Health Education
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• v.18 no.3
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• pp.55-68
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• 2017

Objectives: Republic of Korea has entered an aged society, recently. As chronic diseases increase, elderly inpatients has been increasing and they have used caregivers for convenience. Accordingly, this study aims to investigate the oral health knowledge and attitude of caregivers on oral health management of elderly inpatients, which would affect the general health and quality of life. Methods: A survey questionnaire was distributed to the caregiver(n=165), at a neurosurgery or orthopedic hospital inpatient ward in Seoul, Gyeonggi-do from April 1 to 14, 2017. We analyzed the data with descriptive statistics analysis, chi-squared analysis and logistic regression analysis by using SPSS 23.0. Results: The response rate to the questionnaire was 92%. Oral health management provided by caregivers to inpatients in the elderly was prevention of oral diseases(92.8%), tooth brushing (89.5%), use of oral care products(68.4%), denture cleaning(90.8%) and oral cleaning(90.8%). Frequency analysis of oral health management in accordance with the educational needs of caregivers was all confirmed statistically significant(p<0.05). In the logistics regression model, oral health knowledge was significantly associated with low oral cleaning(OR=1.58) and oral health attitude was significantly associated with high denture cleaning(OR=1.29) and oral cleaning(OR=1.28) after adjustment for other covariates including gender, age, certification, education level, ward, working years. Conclusions: It is necessary to expand the scope and improve the quality of education that can change the attitudes and behaviors of the caregivers on the oral health management of the elderly on the basis of the current oral health education.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.574-586
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• 2019

This study was conducted to obtain meaningful information about job management of child care center teachers, who take charge of child care policy at the front line, social meaning of which is being greatly highlighted these days. Especially, the research was designed with causal relationships in mind, in which certain job-related thoughts or consciousness forms attitudes, thus leading to behavior. In this light, the present study selected the following variables for analysis: job attitudes including job calling, job engagement, and job burnout; and job behavior such as creative behavior, active behavior, and ethical behavior. Data collected from 209 child care center teachers' response to structured questionnaires was analyzed, using t-test, one-way analysis of variance (one-way ANOVA), and hierarchical regression analysis. The results indicate that job burnout increased at a statistically significant level as extra workhours increased, and that only job engagement, among job attitude variables, and creative behavior and active behaviors, among job behavior variables, had significant effects. Moreover, job engagement was the only variable that was found to work as a mediator in relationships between job calling and active behavior.