• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.27-35
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• 2019

The existing middle-long span railway bridge has been mainly applied to steel box girder bridges. However, the steel box girder bridges have disadvantages in securing the space under the bridge, and the main girder is made of a thin plate box shape, resulting in a ringing noise due to the vibration. Many complaints about noise have been raised. For this reason, there is a need for the development of long railway bridges that can replace steel box girder bridges. In this paper, the characteristics of the steel composite railway bridge currently developed were introduced and a time history analysis was conducted using MIDAS Civil reflecting the speed of KTX load for 40m and 50m bridges. In addition, from the analysis results, the dynamic behavior of target bridges were verified and it was examined whether they meet the dynamic performance criteria proposed in the railway design standards. As a result, all of the bridges under review satisfied the dynamic safety criteria, however, in case of 40m of span, the vertical acceleration value was very large. In order to solve this problem, authors proposed the improvement plan and corrected the cross section to confirm that the vertical acceleration decreased.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.9 no.2
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• pp.174-179
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• 1998

Objective：Present study investigated the relationship between mothers' self-perception and perception of children's problems. Method：Subjects were 63 children, mothers, who visited child & adolescent psychiatric clinic. Their mothers completed Minnesota Mulpiphasic Personality Inventory(MMPI) & Korean Personality Inventory for Children(KPI-C). Correlation between validity scales of mothers' MMPI and validity scales of KPI-C was analysed, and then we divided subjects into two group(High & Low Group) according to the MMPI validity scales, and compared KPI-C's validity scales by student t-test. Result：There were significant positive correlation(r=.30) between K scale of MMPI and L scale of KPI-C, significant negative correlation(r=-.32) F scale of MMPI and L scale of KPI-C. The Means of T scores did show significant difference according to MMPI F, K scales in KPI-C L scale, to MMPI L scale in KPI-C F scale. Conclusion：These results indicated that defensive mothers tend to perceive her child's problems more defensively. However mothers who exaggerate their problem more severely, do not exaggerate their children's problem. Therefore, these result suggested that we should be careful not to underestimate children's problem whose mother elevated in K scale of MMPI.

• Korean Journal of Psychosomatic Medicine
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• v.11 no.1
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• pp.36-43
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• 2003

Objectives: The purpose of this study was to evaluate the difference of cognitve function among patients with posttraumatic stress disorder according to severity of symptoms. Methods: The subjects were 90 psychiatric inpatients and outpatients with posttraumatic stress disorer(by DSM-IV criteria) after traffic accident. The severity of symptoms was assessed by MMPI subscales; depression, psychasthenia, schizophrenia. The impairment of cognitive function was assessed by Korean Wechsler Intelligence Scale(K-WAIS). Based on scores of the MMPI subscales, the patients were divided into high group(above 70 percentile) and low group(below 30 percentile). We estimated the difference of the K-WAIS score and subtest score in the low group and high group of the MMPI subscales by indedpendent t-test. Results: The scores of high group is significantly higher in the subtests of information, vocabulary, similarity, picture completion, and picture arrangement than the low group for psychasthenia subscale of MMPI. And the score of high group is significantly higher in full scale I.Q., verbal I.Q., performance I.Q., verbal subscales except digit span and simiarity, and performance subscales than low group for schiozphrenia subscale of MMPI. Conclusion: It was found cognitive function was more impaired in the group of PTSD with severe symptom compared to the group of PTSD with mild symptoms. We suggest that psychiatrist should consider various cognitive approaches as well as pharmacotherapy in the management of PTSD.

• Korean Security Journal
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• no.44
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• pp.37-58
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• 2015

The purpose of this study was to verify the effect of passion on major students for security martial arts. Participants were selected 393 undergraduate students who study security martial arts. Sampling was used by purposive sample method. Measurements were used with multi-dimensional passion and motivation scales. Statistic was executed descriptive statistics, exploratory factor analysis, Pearson's correlation and multiple linear regression. The results of this study were as follows: First, motivation of student for security martial arts has influencing relationship with harmonious passion. Second, motivation has influencing relationship with obsessive passion. Third, motivation has influencing relationship with sense of unity. Forth, motivation has influencing relationship with preference of passion. Fifth, motivation has influencing relationship with value of passion. Sixth, motivation has influencing relationship with investment of passion. That is, internal motivation such as giving value and inner satisfaction gives positive effect to passion above mentioned factors but a motivation gives negative effect to passion.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.241-256
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• 2010

This study intends to develop an aerodynamic girder for suspension bridge with width corresponding to 1/70 of the main span length. In the first step of present study, parametric study for the effects of major structural properties on aerodynamic stability of bridges was performed. The span length and natural frequency of bridges were found to be free from girder width, girder height, and aspect ratio of width to height. The empirical equation according to confidence interval was proposed to estimate the natural frequencies of bridges from span length. From the sensitivity analysis, it was revealed that the torsional frequency was dominant parameter among various structural properties that affected flutter velocity mostly. The final aerodynamic bridge section which satisfied the flutter criteria was found from section wind tunnel tests for 30 cross sectional models. The aerodynamic stability of the developed cross section was verified by multimode flutter analysis. The present economical cross section can be used for long span suspension bridge.

• Korean Journal of School Psychology
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• v.8 no.2
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• pp.133-152
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• 2011

This is a short-term longitudinal study investigating the relationships between changes in mental health and academic burnout among Korean middle school students. Study sample consisted of 409 middle school students in Seoul provision, with 161 male, 216 female, and 32 unidentified. Both Symptom Check List(SCL-47) and Maslach Burnout Inventory-Student Survey(MBI-SS) were used. In order to examine the pattern of changes in mental health and academic burnout among students, standardized residuals were calculated using regression equations which were then put into canonical correlation analysis. The results of this study are as follows. First, according to Function 1, among sub-factors of mental health, decreases in depression, compulsion, anxiety, and hostility were particularly associated with decreases in exhaustion and cynicism among academic burnout. Put in another way, students who showed increases in depression, compulsion, anxiety, and hostility experienced more academic exhaustion and cynicism. Second, according to Function 2, increases in phobic anxiety, compulsion with decreases in anxiety, depression were associated with decrease in academic exhaustion and increase in cynicism. Considering Russell's dimensional theory of emotion, Function 1 showed that mental health symptoms including both aroused and non-aroused affects were related with increases in exhaustion and cynicism while Function 2 showed that mental health symptoms including only aroused aspects were related with decrease in exhaustion and increase in cynicism. Thus, a conclusive intervention program seems to be required to deal with both aroused and non-aroused affects of students who are experiencing increased exhaustion and cynicism. On the other hand, an intervention program focused on aroused affects seems appropriate to students who are experiencing decreased exhaustion and increased cynicism. This study has its value in that it has enhanced understanding of students in school and counseling settings by revealing the relationships between mental health and academic burnout among adolescents and suggested differentiated intervention strategies based on patterns of students' academic burnout.

• Journal of Korean Society of Steel Construction
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• v.29 no.6
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• pp.487-495
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• 2017

Recently rapid-transit railway systems have been constructed in many developing countries due to its advantages in congestions and environmental problems. Railway bridges show many different aspects compared to road bridges and passenger comfort and traffic safety are one of them. In particular, deflection and acceleration due to repeated vibration characteristics have a structural weakness that can cause undesirable response. Especially steel railway bridges have been known to have weaknesses due to its relatively light weights compared to concrete bridges. The purpose of this study is to analyze the dynamic response of steel box girder bridges due to passing trains then propose the appropriate method to mitigate the level of vibration in terms of accelerations. Three steel railway bridges are tested and the numerical model to analyze the dynamic response of the bridge by passing train are developed. For the verification of the model, the natural frequency extracted using the acceleration data measured in the bridge is compared with the natural frequency of the numerical model. To mitigate the acceleration level of the bridge, parametric studies are performed to find the effectiveness of the method. Based on the analysis, the appropriate method is proposed for decreasing the acceleration of the bridge for passenger comfort and traffic safety.

• Journal of Korean Elementary Science Education
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• v.40 no.4
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• pp.421-432
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• 2021

This study compared science academic passion between elementary general and science-gifted students. A science academic passion test was conducted for fifth-sixth graders at an elementary school, and two gifted science education institutes in Seoul, with 95 and 92 students selected for the test. The result analysis revealed that the science-gifted students' science intellectual passion was significantly higher than general students, regardless of grade and gender. Also, the scores of general students were high in the order of "harmonious passion," "importance," "like," "time/energy investment," and "obsessive passion." The differences in scores between all sub-domains were statistically substantial. Moreover, there were no considerable differences in scores of the science-gifted students among the "important," "like," and "harmonious passion." However, the scores in these three domains were higher than that of "time/energy investment" and "obsessive passion." In addition, the "time/energy investment" score was higher than that of "obsessive passion." The differences in science academic passion by grade and gender were not statistically significant regardless of whether or not a student was science gifted. These results suggest that science academic passion characterizes science-gifted students rather than personal characteristics such as grade or gender.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1A
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• pp.105-113
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• 2008

Solar radiation induces non-uniform temperature distribution in the bridge structure depending on the shape of the structure and shadows cast on it. Especially in the case of curved steel box girder bridges, non-uniform temperature distribution caused by solar radiation may lead to unusual load effects enough to damage the support or even topple the whole curved bridge structure if not designed properly. At present, it is very difficult to design bridges in relation to solar radiation because it is not known exactly how varying temperature distribution affects bridges; at least not specific enough for adoption in design. Standard regulations related to this matter are likewise not complete. In this study, the thermal behavior of curved steel box girder bridges is analyzed while taking the solar radiation effect into consideration. For the analysis, a method of predicting the 3-dimensional temperature distribution of curved bridges was developed. It uses a theoretical solar radiation energy equation together with a commercial FEM program. The behavior of the curved steel box girder bridges was examined using the developed method, while taking into consideration the diverse range of bridge azimuth angles and radii. This study also provides reference data for the thermal design of curved steel box girder bridges under solar radiation, which can be used to develop design guidelines.

• Korean Journal of Biological Psychiatry
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• v.24 no.3
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• pp.129-133
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• 2017

Objectives Obsessive-compulsive disorder (OCD) is a disabling psychiatric disorder, and more attention is recently paid on the quality of life (QoL) in OCD patients. The Euro-QoL-5D (EQ-5D) is a widely used self-report to calculate a single score which represents 'health utilities'. The aim of this study was to assess the health-related QoL for patients with OCD using the EQ-5D and to examine the relationship between health-related QoL and symptom severity. Methods Seventy-three patients with a Diagnostic and Statistical Manual of Mental Disorders (DSM-5) diagnosis of OCD were recruited from the outpatient clinic in Seoul National University Hospital. Symptom severity was assessed using the Yale-Brown Obsessive-Compulsive Scale (YBOCS), and QoL was assessed with the EQ-5D-5L questionnaire. Using Korean valuation study, a single score of QoL was calculated. Results Most of the OCD patients were relatively young (< 45 years) with the mean YBOCS total score of 19.33. The mean EQ-5D score was 0.71 and significantly correlated with symptom severity (r = -0.483, p < 0.001). 25% of the EQ-5D score was predicted by the YBOCS total score (b = -0.011, p < 0.001) by regression analysis. Conclusions OCD patients suffer from lower health-related QoL and QoL significantly decreased as symptom severity increased. The results of the EQ-5D would enable further studies on QoL comparison across medical disease and mental disorders.