• Geotechnical Engineering
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• v.14 no.5
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• pp.5-16
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• 1998

2-D numerical methods have been applied to analyze the stability of tunnels because of computation efficiency, though the ground around the tunnel under construction shows 3-D reformational behaviour due to the transverse and longitudinal arching effects. Load distribution factors are introduced to the 2-D analysis for the consideration of the effects of the tunnel advance in three dimensions. The load distribution factors influence significantly the ground deformation and the load of primary supports like shotcrete and rockbolts. According to the previous studies for 3-D numerical studies. it was shown that load distribution factors were heavily dependent on the ground deformational properties, tunnel size and the advance length of a tunnel. However, as the quantitative methods evaluating the factors have not been presented yet, constant values have been assigned to the factors for 2-D analysis even if the conditions for tunnel design are different. Accordingly, this paper presents the method to evaluate quantitatively the load distribution factors through the regression analysis of 3-D analysis data on 72 design cases. Also, new modification to the load distribution factors are suggested for the ring-cut excavation method because the conventional 2-D analysis is not able to consider the support effects of the core left on the tunnel face.

• Journal of The Korean Association For Science Education
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• v.16 no.3
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• pp.314-328
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• 1996

This study investigated the literature about science process skills' evaluation to analyse transition of evaluation objectives before and after a Scholastic Ability Test for College Entrance. In the literature survey the researcher established a 3 dimensional science assessment framework with X axis as science concept, Y axis as science process skills and Z axis as problem context. In order to analysis and compare each items the researcher selected 210 items from the 1st to the 7th trials and 138 items from the 1st to 4th Scholastic Ability Test for College Entrance and sampled 2873 science achievement test items from 10 high schools. In accordance with this taxonomy the researcher analysed and compared science process skills item forms. The following results were drawn : The items were evenly distributed in all the four areas(Earth Science, Biology, Physics and Chemistry) of the science concept domain, but they were heavily concentrated on data analysis and drawing a conclusion in science process domain. In the domain of problem context school context was the majority. In spite of distribution like this the ratio on science process skills measurement items and science achievement test items was increased after the Scholastic Ability Test for College Entrance was given. Also the ratio on item expression type was increased. Item form was almost 5 options selection type in the national level test. Although there were 4 options selection type, 5 options selection type, short answer type, essay type in school level test, rising from 33.1% to 65.5% on 5 options selection type is exhibited. This study showed that the school level item form was better various than the nation level. This point like this is the evidence for the improvement toward the science process skills test and influenced by Scholastic Ability Test for College Entrance. The ratio on the item which joined with the 3 axes had a mean of 99.3% in nation level test and mean 44.9% in school achievement test level. But the ratio in the school achievement test level increased after the Scholastic Ability Test for College Entrance was given. In view of this study we must furthermore study the item types which can evaluate valjdately science process skill's five stage each and evaluation method by the high school students' problem solving patterns and features in scientific inquiry on all science process skills elements.

• Anxiety and mood
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• v.10 no.2
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• pp.95-102
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• 2014

Objective : Previous research showed that childhood trauma or domestic violence resulted in difficulties in controlling emotion and problem solving and vulnerability to psychiatric disorders. To understand the long term effect of childhood trauma, this study investigated their influences on cognitive processing of anger-evoking event and anger behavior among prisoners. Methods : All data were collected from 198 prisoners off our districts in Korea. After they consented to participate, prison officer distributed a questionnaire that included scales to demographic measure, childhood abuse (emotional abuse, physical abuse, and neglect), cognitive response of anger (attentional focus, suspicion, rumination, and hostile attitude) and behavior of anger (impulsive reaction, verbal aggression, physical confrontation, and indirect expression). For statistical analyses, SPSS 18.0 were used and path coefficients were evaluated from the structural equational modeling using LISREL 8.52. Results : Almost 50% of prisoners of our sample experienced one or more trauma during childhood. Then we tested the long term effect of childhood trauma on anger response by structural equation modeling. As expected, childhood trauma was associated with cognitive processing of anger-evoking event and anger behavior. More specifically, emotional abuse (${\beta}$=0.21, p<0.01) predicted suspicion which in turn associated with impulsive reaction (${\beta}$=0.73, p<0.001) and verbal aggression (${\beta}$=0.87, p<0.001). Emotional abuse (${\beta}$=0.24, p<0.01) also predicted hostile attitude which associated with physical confrontation (${\beta}$=0.80, p<0.001) and indirect expression (${\beta}$=0.80, p<0.001). Interestingly, physical abuse associated directly with impulsive reaction (${\beta}$=0.23, p<0.01) and indirect expression (${\beta}$=0.17, p<0.05). Neglect predicted rumination (${\beta}$=0.15, p <0.05) which associated with indirect expression marginally (${\beta}$=0.11, P<0.10). Conclusion : The results of this study, suggest longitudinal and harmful effect of childhood trauma on difficulties in controlling anger. Especially, it was revealed that childhood abuse related with processing anger evoking events more suspicious and hostile and then various anger-expressing behaviors.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4727-4731
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• 2013

Background: There have been no large-scale population-based studies to estimate the subsequent risk of primary liver cancer (PLC) among patients with pyogenic liver abscess (PLA). This study aimed to provide relevant data. Materials and Methods: The Taiwan Longitudinal Health Insurance Database for the years 2000 and 2005 was used. The PLA group were adult inpatients who were newly diagnosed with PLA from 2000 to 2008. The control group was randomly selected and matched with the PLA group in terms of age, sex, and date in which medical treatment was sought other than for PLA. Results: There were 1,987 patients each in the PLA and control groups. In total, 56 had PLC, 48 (2.4%, 601.5 per 100,000 person-years) from the PLA group, and 8 from the control group. After adjusting for potential covariates, the hazard ratio of PLC for the PLA group was 3.4 times that of the control group (95% confidence interval = 1.6-7.3, p <0.001). The PLC risk for the PLA group was significantly higher within the first year after PLA diagnosis (hazard ratio: 35.4) as compared with the control group and became insignificant (hazard ratio: 2.0, 95% confidence interval = 0.8-4.9) more than one year after PLA diagnosis. Conclusions: Patients with PLA have a higher rate of PLC than matched controls, especially within the first year after the diagnosis of PLA, suggesting PLA is a warning sign for PLC.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.5
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• pp.349-354
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• 2011

Introduction: Mandibular third molar extraction is one of the most common procedures performed in oral and maxillofacial surgery units. Although the overall complication rate is low with most complications being minor, mandibular third molar removal is so common that the population morbidity of complications might be significant. Therefore, efforts to limit intraoperative or postoperative complications might have a significant impact in terms of enhancing the patient outcome. The aims of this study were to identify the position and angulation associated complications after mandibular third molar extractions. Materials and Methods: This study surveyed 568 patients who had a mandibular third molar extracted, showed clinical complications and underwent a radiographic measurement of the available space, depth and spatial relationship. Results: The results obtained were as follows: 1. The complications were a dry socket, nerve injury, root rest, infection, bleeding, hamatoma, and adjacent teeth injury. 2. There were no significant differences between the complication and ramus relationship (available space) of the mandibular third molar. 3. There were no significant differences between the complications and depth of the mandibular third molar. 4. There were no significant differences between the complications and spatial relationship of the mandibular third molar. Conclusion: There were no significant differences in the complication rate, ramus relationship, depth and spatial relationship of the mandibular third molar. This suggests that the position and angulation of the mandibular third molar may not have an impact on the complications. The relationship between the position and angulation of the mandibular third molar, and complications deserves a further study using longitudinal data.

• Journal of Korea Water Resources Association
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• v.41 no.9
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• pp.929-941
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• 2008

The objectives of this study are to propose a system for combined use of a hydrologic and a hydraulic model for urban flood forecast model and to evaluate the system on the $300km^2$ Jungrang urban watershed area, which is relatively large area as an urban watershed and consequently composed of very complex drainage pipes and streams with different land uses. In this study, SWMM for hydrologic model and HEC-RAS for hydraulic model are used and the study area is divided into 25 subbasins. The SWMM model is used for sewer drainage analysis within each subbasin, while HEC-RAS for unstready flow analysis in the channel streams. Also, this study develops a GUI system composed of mean areal precipitation input component, hydrologic runoff analysis component, stream channel routing component, and graphical representation of model output. The proposed system was calibrated for the model parameters and verified for the model applicability by using the observation data. The correlation coefficients between simulated and observed flows at the 2 important locations were ranged on 0.83-0.98, while the coefficients of model efficiency on 0.60-0.92 for the verification periods. This study also provided the possibilities of manhole overflows and channel bank inundation through the calculated water profile of longitudinal and channel sections, respectively. It can be concluded that the proposed system can be used as a surface runoff and channel routing models for urban flood forecast over the large watershed area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.485-491
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• 2016

The purpose of this study was to identify the effects of a visiting exercise program for physical activity promotion on physical (grip strength, static balance) and psychological (depression, perceived health status) function of frail elderly patients receiving home visiting service care. Subjects included a total of 49 patients; 24 in the control group and 25 in the experimental group. The visiting exercise program was carried out 16 times for 8 weeks. The collected data were analyzed by ${\chi}^2-test$ and t-test using SPSS/WIN 21.0 program. There was a significant improvement in the left grip strength (t=2.19, p<.000), right grip strength (t=5.07, p=.032), static balance (t=3.98, p=.050), and depression (t=-8.83, p=.009) in the experimental group compared with the control group. The visiting exercise program for physical activity promotion was effective on physical and psychological functions for frail elderly patients receiving home visiting service care. Further research is needed in a longitudinal study incorporating various centers to examine the maintenance of such effects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.337-345
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• 2020

This study analyzed the longitudinal trajectories of father's depression and the changes of relevant parenting practice in fathers' as well as the problematic behaviors and school adaptation of their children. To address these goals, the data from 1,172 samples from the 4th to 8th Korean Children and Youth Panel Survey (KCYPS) was analyzed. The results of this study indicated that the fathers' depressive levels are classified into three latent groups: 1) the high-changing group, 2) the middle-low changing group, and 3) the low-low changing group. The results also revealed that the fathers within the low-low changing group practiced more authoritative but permissive parenting than the fathers in the two other groups. Children from high-changing group showed more problematic behaviors than the children of the two other groups. In addition, the children from the low-low changing group reported higher school adjustment such as academic achievements, and relationships with peers and teachers. Based on these findings, the study discusses the implications for social work practice and further studies.

• Journal of Preventive Medicine and Public Health
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• v.40 no.5
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• pp.388-396
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• 2007

Objectives: The purpose of this study was to examine the relationship between the differences in employment status and self assessed health in Korea. Methods: We analyzed 4 year follow-up data generated by the Korean Labor and Income Panel Study(KLIPS), which was conducted on 1,207 men and 582 women who had undergone a change in employment status. The study subjects were placed into 1 of the following 4 groups based on their employment history; Non-precarious workers, Precarious to non-precarious workers, Non-precarious to precarious workers and Precarious workers. Logistic regression was then used to examine the relationship between the changes in employment status and self assessed health. Results: When males were considered, self assessed health was better among the precarious to non-precarious workers (OR 1.58, 95% CI=1.57-1.60) and the precarious workers (OR 1.29, 95% CI=1.28-1.30) than in the non-precarious workers, after adjusting for age, socioeconomic status (education level, occupational class, marital status, average equivalent household income and average number of hours worked per week), health behavior (smoking, drinking and exercise) and medical service access (regular medical examination, have chronic disease or hospitalized within 1 year). When female workers were considered, the precarious to non-precarious workers (OR 1.89, 95% CI=1.86-1.92), non-precarious to precarious workers(OR 1.24, 95% CI=1.23-1.26) and precarious workers (OR 1.27, 95% CI=1.25-1.28) all reported poorer health than the non-precarious workers after adjusting for the aforementioned factors. Conclusions: This study showed that changes in employment status were associated with differences in self assessed health among men and women. Specifically, the results of this study showed that a corresponding positive outcome based on self assessed health was greater for employees that changed from precarious to non-precarious jobs and for male employees with precarious jobs., whereas female employees with non-precarious jobs had higher self assessed health. However, additional longitudinal studies on the health effects of employment status should be conducted.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.3
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• pp.232-242
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• 2015

For stealth performance consideration, many UAV designs are adopting tailless lambda-shaped configurations which are likely to have unsteady dynamic characteristics. In order to control such UAVs through automatic flight control system, more accurate estimation of dynamic stability derivatives becomes essential. In this paper, dynamic stability derivatives of a tailless lambda-shaped UAV are estimated through numerically simulated forced oscillation method incorporating dynamic mesh technique. First, the methodology is validated by benchmarking the CFD results against previously published experimental results of the Standard Dynamics Model(SDM). The dependency of initial angle of attack, oscillation frequency and oscillation magnitude on the dynamic stability derivatives of a tailless UAV configuration is then studied. The results show reasonable agreements with experimental reference data and prove the validity and efficiency of the concept of using CFD to estimate the dynamic derivatives.