• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.1
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• pp.39-47
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• 2004

In this paper, the defects of two-dimensional anisotropic elastic bodies are identified by using the boundary element method. The use of numerical models that contain only boundary integral terns reduces the dimensionality of the problem by one. This advantage is particularly important in problems such as crack mechanics. Avoiding domain meshing is also particularly advantageous in the solution of inverse problems since it overcomes mesh perturbations and simplifies the procedure. In this paper, nondestructive approaches for the existing isotropic materials are extended to analyze the elastic bodies made of anisotropic materials such as composites. After verifying that the proposing boundary element model is in good agreement with numerical results reported by other investigators, the effect of noise in the measurements on the identifiability is studied with respect to different design parameters of layered composites. Sample studies are carried out for various layup configurations and loading conditions. The effects of the layup sequences in detecting flaw of composites is explored in this paper.

• Journal of Korean Academy of Nursing
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• v.29 no.3
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• pp.585-595
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• 1999

The purpose of this study was to examine the predictors of burnout among informal caregivers of older adults. One hundred thirty seven caregivers who had provided care to older adults over 60 years of age for more than one month were included in the study. Most of the caregivers were white (91%) and female (78%). Mean ages of the caregivers were 64 years and 78% of them were married. Seventy percent of the older adults suffered from Alzheimer and related disease. In this study, caregivers reported that they experienced burnout once a month. The scores of emotional exhaustion and reduced personal accomplishment of the caregivers were in the moderate burnout range. To examine the predictors of burnout, discriminant analysis was used. Caregivers were divided by two groups based on the sum of scores (cutpoint＝6) on three dimensions of burnout after each dimension was categorized into high(3), moderate(2), and low(1). Nine predictors were included in the analysis : Caregiver's age, employment status, Instrumental Activities of Daily Living (IADL) of the older adult, presence of dementia of the older adult, caregiver's empathy toward the older adult (emotional and cognitive), and 3 coping strategies (negative, problem-focused, cognitive reconstructioning). Caregivers who reported high burnout showed higher cognitive empathy toward the older adults than those who showed low burnout. Caregivers who experienced high burnout used negative coping more often, and cognitive reconstructioning coping and problem focused coping less often than their counterparts. Wilks' Lambda was .78 indicating that differences between the two groups were significant. Cognitive empathy and cognitive reconstructioning coping showed high standardized canonical discriminat function coefficients over .40. Discriminant function with 9 predictors correctly classified 71% of the sample. In conclusion, informal caregivers also experienced certain level of burnout. Cognitive empathy and coping strategies predicted burnout experience of the caregivers. Based on this study, nursing intervention to the informal caregivers to improve their cognitive empathy toward the older adults and to modify their coping strategies in a way to reduce burnout experience can be applied. Further research to develop effective nursing interventions for the purpose of reducing burnout experience by modifying predictors was suggested.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.474-482
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• 2014

PURPOSE. To assess removable prosthetic restoration tolerance according to the patient section of the short form of the Gagging Problem Assessment Questionnaire (GPA-pa SF) and the influence of gender, education level and prosthesis type and denture-related mucosal irritation on the GPA-pa SF scores before treatment and over a period of two months after prosthesis insertion. MATERIALS AND METHODS. 130 participants who required removable prosthesis were surveyed with a standard form that included questions regarding age, gender, education level, dental attendance, and prosthetic restoration type. Participants answered the GPA-pa SF before restoration (T0) and 1 day (T1), 2 days (T2), 15 days (T3), 1 month (T4), and 2 months (T5) after prosthesis insertion. RESULTS. Of the 130 participants, 110 participants completed the prosthetic restoration procedure, but only 93 of these were able to use the prosthesis over the two-month period. The mean GPA-pa SF score obtained at T0 was higher than the scores obtained at the other periods in the total of the sample. Significant difference was present between mean scores obtained at T0-T1 and T2-T3 than scores obtained at other periods (P<.05). Female participants and participants with denture-related mucosal irritation had higher GPA-pa SF scores at all time points analysed. Significant difference was present between mean GPA-pa SF scores obtained at T2-T3 than scores obtained at other periods for females and participants with denture-related mucosal irritation (P<.05). Education level and prosthesis type did not significantly influence the GPA-pa SF score at any time point analysed (P>.05). CONCLUSION. GPA-pa SF scores were higher before the restoration procedure began, and decreased over time with the use of prosthesis. Gender and denture-related mucosal irritation affected the GPA-pa SF scores.

• Journal of Preventive Medicine and Public Health
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• v.37 no.3
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• pp.232-237
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• 2004

Objectives : The study was designed to test if alcohol use and alcohol-related problems among adolescent females are related to their parents' level of alcohol problems. Methods : In 2001, a stratified sample of 2077 adolescent females, grades 10-11, from twelve female-only high schools located in a large metropolitan city in the Republic of Korea completed a questionnaire about alcohol use, parental attention, and parental alcohol consumption, and other risk and protective factors. Data were analyzed with chi-square and regression analyses. Results : Nearly 63% of the student drinkers had experienced at least one to two alcohol-related problems in their lives. Two-thirds of all 2077 students indicated that at least one of their parents had an alcohol-related problem and that approximately 29% had experienced several problems. Results of random effects ordinal logistic regression analyses suggest a dose-response relationship between parental and youth alcohol-related problems. Youth who report having parents with some and many alcohol problems were 30% (Odds Ratios [OR] = 1.30; 95% Confidence Interval [CI] = 1.10 - 1.53) and 55% (OR = 1.55; 95%CI = 1.23 - 1.95) more likely to experience alcohol-related problems than youth whose parents do not have alcohol problems, respectively, after statistically adjusting for important covariates. Conclusions : This study presents evidence that alcohol-related problems among adolescent female students is highly prevalent. Also, the study findings reveal a high percentage of parents with alcohol problems, as reported by students. This study presents evidence of what might be a hidden problem among adults and youths in the Republic of Korea that merits serious attention.

• Anxiety and mood
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• v.14 no.2
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• pp.120-126
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• 2018

Objective : Psychopathy has been suggested as one of the important cause of violence in patients with schizophrenia. The purpose of this study was to evaluate the personality disorder in criminal schizophrenia. Methods : A total of 187 criminal schizophrenia participated in this study. All participants filled out the Korean Inventory of Interpersonal Problem Personality Disorder Scales (K-IIP-PD), Psychopathic Personality Inventory-Revised (PPI-R), Personality Assessment Inventory (PAI). Using the correlations between the scales, we investigated whether K-IIP-PD could be used to evaluate personality disorder in criminal schizophrenia. Moreover, participants were divided into two groups of psychopathic and nonpsychopathic schizophrenics, and scores of K-IIP-PD were compared between the two subgroups. Results : The overall correlation between the scales was very high. In particular, sum of 3 item scores (interprsonal sensitivity+interpersonal ambivalence+aggression) and aggression of K-IIP-PD were highly correlated with PPI-R and PAI. Total score of personality disorder scale and subscales were higher in psychopathic schizophrenic group compared to nonpsychopathic schizophrenic group. Conclusion : The K-IIP-PD could be used to assess the antisocial and aggressive nature of criminal schizophrenia. Further studies in various clinical groups including the general population are required.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.33.1-33.1
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• 2021

The overprediction of the number of satellite galaxies in the LCDM paradigm compared to that of the Milky Way (MW) and M31 (the "missing satellites" problem) has been a long-standing issue. Recently, a large host-to-host scatter of satellite populations has been recognized both from an observational perspective with a larger sample and from a theoretical perspective including baryons, and it is crucial to collect diverse and complete samples with a large survey coverage to investigate underlying factors contributing to the diversity. In this study, we discuss the diversity in terms of galaxy assembly history, using satellite populations of both observed systems and simulated systems from IllustrisTNG. In addition to previously studied satellite systems, we identify satellite candidates from 25deg2 of Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) Wide layer around NGC 4437, a spiral galaxy of about one-fourth of the MW mass, paired with a ~2 magnitude fainter dwarf spiral galaxy NGC 4592. Using the surface brightness fluctuations (SBF) method, we confirm five dwarf galaxies as members of the NGC 4437 group, resulting in a total of seven members. The group consists of two distinct subgroups, the NGC 4437 subgroup and the NGC 4592 subgroup, which resembles the relationship between the MW and M31. The number of satellites is larger than that of other observed and simulated galaxy groups in the same host stellar mass range. However, the discrepancy decreases if compared with galaxy groups with similar magnitude gaps (V12 ~ 2), defined as the V-band magnitude difference between the two brightest galaxies in the group. Using simulated galaxy groups in IllustrisTNG, we find that groups with smaller V12 have richer satellite systems, host more massive dark matter halos, and have assembled more recently. These results show that the host-to-host scatter of satellite populations can be attributed to the diversity in galaxy assembly history and be probed by V12 to some degree and that NGC 4437 group is likely a recently assembled galaxy group with a large halo mass compared to galaxy groups of similar luminosity.

• Nuclear Engineering and Technology
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• v.56 no.8
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• pp.2948-2957
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• 2024

High-order harmonic techniques can be used to recreate neutron flux distributions in reactor cores using the neutron diffusion equation. However, traditional source iteration and source correction iteration techniques have sluggish convergence rates and protracted calculation periods. The correctness of the implicitly restarted Arnoldi method (IRAM) in resolving the eigenvalue problems of the one-dimensional and two-dimensional neutron diffusion equations was confirmed by computing the benchmark problems SLAB_1D_1G and two-dimensional steady-state TWIGL using IRAM. By integrating Galerkin projection with Proper Orthogonal Decomposition (POD) techniques, a POD-Galerkin reduced-order model was developed and the IRAM model was used as the full-order model. For 14 macroscopic cross-section values, the TWIGL benchmark problem was perturbed within a 20% range. We extracted 100 sample points using the Latin hypercube sampling method, and 70% of the samples were used as the testing set to assess the performance of the reduced-order model The remaining 30% were utilized as the training set to develop the reduced-order model, which was employed to rebuild the TWIGL benchmark problem. The reduced-order model demonstrates good flexibility and can efficiently and accurately forecast the effective multiplication factor and neutron flux distribution in the core. The reduced-order model predicts k_eff and neutron flux distribution with a high degree of agreement compared to the full-order model. Additionally, the reduced-order model's computation time is only 10.18% of that required by the full-order model.The neutron flux distribution of the steady-state TWIGL benchmark was recreated using the reduced-order model. The obtained results indicate that the reduced-order model can accurately predict the k_eff and neutron flux distribution of the steady-state TWIGL benchmark.Overall, the proposed technique not only has the potential to accurately project neutron flux distributions in transient settings, but is also relevant for reconstructing neutron flux distributions in steady-state conditions; thus, its applicability is bound to increase in the future.

• Journal of Korean Academy of Nursing
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• v.36 no.1
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• pp.169-178
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• 2006

Purpose: The purpose of this study was to examine stress, coping, and immune response effects of a psychosocial intervention program based on the PNI model and Stress-Appraisal-Coping for Korean patients with breast cancer. Methods: A nonequivalent control group pretest-posttest design was used. The participants who had survived breast cancer and lived in Wonju city and the surrounding area were assigned to an intervention group (N=21) or a control group(N=18).We conducted a 12-week intervention, 2 hours a day weekly, and measured the variables at baseline, six and twelve weeks later. Dependent variables are: stress, anxiety-depression and anger, and immune response. Results: Patients in the psychosocial intervention program reported significantly less stress perception (U=31.500, p=.023), more problem solving ability and less problem avoidance in coping (U=20.500, p= .013; U=29.500, p=.040), and less anxiety-depression (U=22.000, p=.023). No difference, however, was found in anger and. immune responses between the two groups. Intervention effects were evident at week 6 and 12 for anxiety-depression, and at week 6 for problem avoidance in coping, the same time that NK cell counts and the T8 decreased. Conclusions: These results suggested positive effects of a psychosocial intervention program. However, the results are inconclusive due to the small sample.

• Journal of Gifted/Talented Education
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• v.24 no.6
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• pp.961-974
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• 2014

We analyzed the relationship between the brain Dominance and the scientific creative problem solving utilizing propensity to target Science-Gifted Student (n=159). Brain dominance is divided into left upper brain (LUB), left lower brain (LLB), right lower brain (RLB), and right upper brain (RUB). Creative problem solving skill in science included validity, scientific characteristics, sophistication, originality, and fluency. Analysis of the results of this study showed a high frequency among the four types of the brain dominance is the highest score of LUB in science gifted group. This point was found that the tendency of the analytical and critical thinking that is characteristic of the LUB is strong scientific gifted group. When total sample was divided into high and low groups by scientific creative problem solving scores, in the analysis of the brain dominance score difference between the two groups of students who take advantage of the results of score RUB is compared to the high fluency group score higher than the low group found (p<0.05). The analysis of the correlation between brain dominance and scientific creative problem solving showed that originality and fluency had statistically significant correlation with RUB propensity score (p<0.05). This result suggests that the imaginative and challenging RUB propensity may be related to produce many and original ideas in scientific creative problem solving.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.3
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• pp.303-309
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• 2007

Statement of problem. The effect of gold electroforming on gold alloy was not studied. Purpose. This in vitro study investigate the effect of gold electroforming on gold-silver-palladium alloy. Material and methods. Three pieces of gold strips had undergone the electroforming procedures on one side and then half of the side again electroformed. The set mode for this study was program 1 ($200{\mu}m$). And the processing time was 15min (1/20 time to form $200{\mu}m$ coping). The confocal laser scanning microscope (PASCAL 5, Carl Zeiss, Bernried, Germany) was used to measure the thickness of the pure gold layer electroformed on the gold strips. Half of the gold strip was coated two times with electroformed gold, and the other half one time. The data from the cone focal laser system was processed to get the vertical profile of the strips and the difference of the vertical height between the double coated and single coated layer was regarded as the thickness of the gold coating. The layer thickness value to built 3D image of the cone-focal laser was set $0.5{\mu}m$. Next to the measurement of the thickness of the coating, the Vicker's hardness test was done. It was performed on the double coated surface, single coated surface and non-coated surface (back side) three times each. Results. The mean thickness value gained from gold electroforming technique was measured to be $22{\mu}m$ for sample 1, $23{\mu}m$ for sample 2, $21{\mu}m$ for sample 3. In the same condition of time, power and the amount of electrolyte, the data showed no difference between samples. According to the results of variance analysis, the differences among the variations in number of coating were statistically insignificant (p>0.05), meaning that the two times of gold electroforming coating did not change the hardness of gold-silver-palladium alloy. Conclusion. The test of thickness of gold coating proved the coherency of the gold electroforming procedure, in other words, when the power, the exposed surface area, processing time and the amount of electrolytes were set same, the same thickness of gold would be coated on. The hardness test showed that the electroformed gold coating did not change the hardness of the gold-silver-palladium alloy when it is coated not more than $45{\mu}m$.