• Nuclear Engineering and Technology
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• v.56 no.9
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• pp.3491-3500
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• 2024

In this work, the hybrid vibro-acoustic model reduction technique that is a physical-modal combined formulation is proposed to accelerate the finite element model updating process of the vibro-acoustic pipeline system. Particularly, the new formulation could provide an effective way of the model updating by preserving the physical DOFs for the direct calibration of the undetermined boundary conditions. The sensitivity based vibro-acoustic model updating is first conducted, and then the undetermined spring constant at the displacement boundary condition is then directly and effectively calibrated by using the proposed hybrid model reduction formulation. The proposed method is implemented in the real nuclear facility to evaluate its performance. In addition, an experimental implementation test using the inverse force identification process is also conducted to demonstrate the reliability of the generated vibro-acoustic FE model through the proposed method.

• Journal of muscle and joint health
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• v.1 no.1
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• pp.97-115
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• 1994

The purpose of this study was to examine the reliability and validity of the observed behaviors of subjects who suffered from low back pain with spinal diseases, Thirty two low back pain patients admitted on the neurosurgical unit in an army hospital were compared with 30 normal controls belonged to an army unit, by means of matching the age, hight and weight. Observed pain behaviors were developed by the researcher on the bases of literature and patient observation. This tool consists of 18 behaviors seperated into two major groups : mutually exclusive and concomittent behaviors. The mutually exclusive behaviors included coding cathegories for 6. body motions assumed by the subjects during the observation session. These 6 standardized motions consisted of sitting from standing first, and serially tying down, reclining, sitting again, and then standing, 6 steps walking. Concomittent behaviors consisted of 12 observable patterns that can be observed systematically from the face, grimacing, bracing, rubbing, walking with arms fixed, support with hands on sitting or standing, guarded movement, limping, unbalaced weightbearing, stopped movement from tying position to sitting, sighing and graoning. Subjects were videotrecorded as they performed a 6-standardized sequence of motions, simultanously researcher measured the time spent performing each motion and step length. Patients were asked torate their subjective pain score on the 10 mm graphic rating scale ranging from 'no pain' to 'sever pain'. For scoring of the pain behaviors, two trained nursing officiers independently and simutanously viewwd each videorecording and checked subject 'pain behaviors at the observational item checklist. The result of the study are summarized as follows : 1. Reability of the observational tool was a=.845. 2. Spearman's rho and percentage agreement were p=.97 and 81.7 persent respectively, that indicate adequate interrater reability of this tool. 3. The sensitivity rate of the tool was .875 while specificity rate .866 for differentiating patient from the normal. 4. When difference in the objective pain indices between patient group and control were compared, there was significant difference of all indices, such as pain behavior(t=7.71, p=.0001). spent time performing motion(t=14.2, p=.0001), step length (t=-10.72, p=.0001). 5. There were differences in the objective indices the subjective pain subgroups (low, medium, high). Differences in the mean score of objective pain behavior (F=6.376. p=.005) and spent time for moyion(F=4.631, p=.018). But there were no significant differences in the step length among the subgroups(F=.667, p=.521). 6. Highly correlated pain behavior items wiyh subjective pain score were 'stopped movement from lying position to sitting', 'limping', 'support with hands on sitting or standing', 'bracing', 'guarding' and 'walking with arms fixed'. In summary, although some of rho behavior items such as sighing and groaning in this study could not be observed because of videotaped datd, the reliability and validity of the over all observation method were satifactory. Thus, the results of the present study demonstrate rye potetional utility of the tool in assessing objective pain complementing self-reported pain in low back pain patients.

• Analytical Science and Technology
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• v.31 no.1
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• pp.23-30
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• 2018

Twenty-two allergy-induced aromatics in children were analyzed using a gas chromatography flame ionization detector (GC-FID) and gas chromatography mass spectrometer (GC-MSD). Analytes were extracted using an automatic Soxhlet extractor and centrifuged for 10 min in a fast freezing centrifuge, and the supernatant was transferred into a 2 mL vial and injected in split mode. Under the established conditions, the calibration curve showed linearity with a correlation coefficient of 0.996 or more. A wide range of sensitivity of 6.7 to 1,859,839 depending on the device characteristics and detector used was shown. The detection limit of the device was 0.0032 to $0.0335{\mu}g/mL$, and the maximum detection limit was less than $0.1{\mu}g/mL$. The detection limit of the method ranged from 0.0033 to $0.1161{\mu}g/mL$. In addition, the limit of quantification ranged from 0.0100 to $0.5422{\mu}g/mL$, with a level of precision ranging from 0.21 % to 4.89 % and a degree of accuracy ranging from 89 % to 111 %. The analytical method developed in this study was applied to commercial products.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.22 no.4
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• pp.262-270
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• 2011

Objectives : The definition of a hidden youth is a young person who has completely withdrawn from society and shut himself or herself away for more than 3 months. Those pathologically-withdrawn youths have become a burden not only to society but also to the family. However, screening of these hidden youths cannot be done easily. This study focused on developing a primary effective screening tool for these hidden youths. Methods : The 42 participants of this study were parents of hidden youths that are between 8 to 25 years old. They were selected from from mental health centers and psychiatric clinics around Seoul and Gyeonggi Province. We also recruited 239 parents of middle and high school students in the Seoul metropolitan area for a control group. In order to decide the concurrent validity of this questionnaire, we used the Symptom Checklist-90-Revision, Children's Depression Inventory, Beck Depression Inven-tory, Social Anxiety Scale for Children-Revised, Social Anxiety and Distress Scale, Avoidant Personality Disorder Scale, and State-Trait Anxiety Inventory for Children. SPSS version 12.0 was used for statistical analysis. Results : Cronbach's alpha values, the reliability coefficient to represent internal consistency, were between 0.396 and 0.935, which showed relatively high internal consistency for this questionnaire. The test-retest coefficient was between 0.68 and 0.78, which was a statistically significant result. In a factor analysis, 4 factors such as avoidance, withdrawal, isolation, and apathy were extracted. In a concurrent validity test with SCL-90-R, the isolation factor showed a statistically-significant relationship with a phobic-anxiety sub-scale, and avoidance and withdrawal sub-scales were remarkably correlated with the interpersonal sensitivity sub-scale. Conclusion : Since the questionnaire for socially withdrawn youths has achieved statistically-satisfactory reliability and validity, it will be a useful method to screen for hidden youths in educational, community, and clinical settings.

• 재활복지
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• v.22 no.4
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• pp.43-58
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• 2018

Swallowing disorders that can affect nutrient intakes and quality of life are commonly shown among the elderly as well as patients with neurogenic disorder. This study verifies the reliability and validity of the Swallowing Disturbance Questionnaire (SDQ), a subjective swallowing disability assessment tool, modified for Koreans' eating habit and cultural sentiment, against 105 stroke patients, in order to help identify early swallowing problems of the elderly. Reliability of internal consistency in the Korean version of SDQ is .601, test-retest reliability is .97, and concurrent validity is .956. Based on 8 points of cut-off score, 46.8% of sensitivity and 81.6% of specificity. Comparing the results of video fluoroscopic study (VFSS), an objective swallowing disorder test with those of Korean version of SDQ, negative predictive value (NPV) and positive predictive value (PPV) was shown as 81% and 53%. The Korean version of SDQ is expected to be a useful testing tool to discriminate swallowing disorders in stroke patients. It has great clinical significance in that swallowing difficulties shown by subjects can be sorted out to request a diagnostic assessment before clinical evaluation by a rehabilitation therapist or ruling out unnecessary exposure to additional tests by accurately identifying stroke patients without swallowing problems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.835-842
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• 2008

The response surface method (RSM) is widely adopted for the structural reliability analysis because of its numerical efficiency. However, the RSM is still time consuming for large-scale applications and sometimes shows large errors in the calculation of sensitivity of reliability index with respect to random variables. Therefore, this study proposes a new RSM in which moving least squares (MLS) approximation is applied. Least squares approximation generally used in the common RSM gives equal weight to the coefficients of the response surface function (RSF). On the other hand, The MLS approximation gives higher weight to the experimental points closer to the design point, which yields the RSF more similar to the limit state at the design point. In the procedure of the proposed method, a linear RSF is constructed initially and then a quadratic RSF is formed using the axial experimental points selected from the reduced region where the design point is likely to exist. The RSF is updated successively by adding one more experimental point to the previously sampled experimental points. In order to demonstrate the effectiveness of the proposed method, mathematical problems and ten-bar truss are considered as numerical examples. As a result, the proposed method shows better accuracy and computational efficiency than the common RSM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.75-89
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• 2006

This paper presents a practical and realistic Life-Cycle Cost (LCC) optimum design methodology of steel bridges considering time effect of bridge reliability under environmental stressors such as corrosion and heavy truck traffics. The LCC functions considered in the LCC optimization consist of initial cost, expected life-cycle maintenance cost and expected life-cycle rehabilitation costs including repair/replacement costs, loss of contents or fatality and injury losses, road user costs, and indirect socio-economic losses. For the assessment of the life-cycle rehabilitation costs, the annual probability of failure which depends upon the prior and updated load and resistance histories should be accounted for. For the purpose, Nowak live load model and a modified corrosion propagation model considering corrosion initiation, corrosion rate, and repainting effect are adopted in this study. The proposed methodology is applied to the LCC optimum design problem of an actual steel box girder bridge with 3 continuous spans (40 m+50 m+40 m=130 m), and various sensitivity analyses of types of steel, local corrosion environments, average daily traffic volume, and discount rates are performed to investigate the effects of various design parameters and conditions on the LCC-effectiveness. From the numerical investigation, it has been observed that local corrosion environments and the number of truck traffics significantly influence the LCC-effective optimum design of steel bridges, and thus realized that these conditions should be considered as crucial parameters for the optimum LCC-effective design.

• Korean Journal of Psychosomatic Medicine
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• v.10 no.2
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• pp.78-91
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• 2002

Objective : The purpose of this study was to develop the somatization rating scale (SRS), and then to use the scale in clinical pracitice. Methods: First, a preliminary survey was conducted for 109 healthy adults to obtain 40 response items. Second, a preliminary questionnaire was completed by 215 healthy subjects. Third, a comparison was made regarding somatization responses among 242 patients (71 with anxiety disorder. 73 with depressive disorder, 47 with somatoform disorder, and 51 with psychosomatic disorder) and 215 healthy subjects. Results : Factor analysis yielded 5 subscales : cardiorespiratory and nervous responses, somatic sensitivity, gastrointestinal responses, general somatic responses, genitourinary, eye and muscular responses. Reliability was computed by administering the SRS to 62 healthy subjects during a 2-week interval. Test-retest reliability for 5 subscales and the total score was significantly high, ranging between .86-.94. Internal consistency was computed, and Cronbach's ${\alpha}$ for 5 subscales ranged between .72-.92, and .95 for the total score. Convergent validity was computed by correlating the 5 subscales and the total score with the total score of the global assessment of recent stress (GARS) scale, the perceived stress questionnaire (PSQ), and the symptom checklist-90-revised (SCL-90-R). The correlations were all at significant levels. Discriminant validity was computed by comparing the total score and the 5 subscale scores of the patient and control groups. Significant differences were found for 5 subscales and the total score. Only the depressive disorder group was siginificantly higher than control group in all the subscale scores and total scores of SRS among 4 patient groups. In somatic sensitivity, only depressive disorder patients were significantly higher than the normal controls, whereas in general somatic subscale, depressive disorder and somatoform disorder groups were significantly higher than the normal controls. In total scores of the SRS, female subjects were significantly higher than males. Conclusion : These results indicate that the SRS is highly reliable and valid, and that it can be utilized as an effective measure for research in stress- and somatization-related fields. The depressive disorder and somatoform disorder groups showed more widespread somatization than the anxiety and psychosomatic disorder groups.

• Journal of radiological science and technology
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• v.32 no.4
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• pp.381-391
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• 2009

Purposes : The purpose of this study was to analyze factors that could affect health of radiological technologists, which is useful for health care and development of programs for health promotion. Methods : Subjects were 234 of radiological technologists who work in general hospitals. Some questionnaires were made about perceptions of health condition and promotional behavior of health for this study. The questionnaires of health perception were 20 items that consist of the present condition of health, health concern and sensitivity. The reliability was sufficient(Cronbach's $\alpha=0.79$). The other questionnaires about health promotion behavior were 47 items that consist of self-realization, health responsibility, exercise, nutrition, personal relationships, and stress management. The results turned out to bewas sufficient (Cronbach's $\alpha=0.93$). Every data was treated statistically, comparison of average(t-test, ANOVA), correlation, and multiple regression. Results : Related factors to health promotion behavior were age, marriage, salary, class of one's position, career, employment, and religion, in general features. In health life habit, related factors were smoke and exercise. Results of health promotion behavior was 2.90 of mean score, 0.37 of standard deviation. Correlations between factors of health perception and health promotion behavior was positive(p<0.01). Health promotion behavior were affected by sensitivity, presents condition of health, exercise, smoke, career. Sensitivity was the most affectable variable, which means that promotional behavior score became higher and higher as the score of sensitivity and present condition were increased. In addition, persons who exercise regularly, had been smoked, and has higher career showed higher score of promotional behavior. Conclusion : Radiological technologists have to keep their health, trying not to infected by a disease. Most of all, no smoking and regular exercise are the most important thing to all of members.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2657-2662
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• 2013

Background: Intraoperative sentinel lymph node biopsy has now become the standard of care for patients with clinically node negative breast cancer for diagnosis and also in order to determine the need for immediate axillary clearance. Several large scale studies confirmed the diagnostic reliability of this method. However, micrometastases are frequently missed on frozen sections. Recent studies showed that both disease free interval and overall survival are significantly affected by the presence of micrometastatic disease. The aim of this study was to determine the sensitivity and specificity of intraoperative frozen section analysis of sentinel lymph nodes (SLNs) for the detection of breast cancer micrometastasis and to evaluate the status of non-sentinel lymph nodes (non-SLNs) in those patients subjected to further axillary sampling. Materials and Methods: We performed a retrospective study on 154 patients who underwent SLN biopsy from January 2008 till October 2011. The SLNs were sectioned at 2 mm intervals and submitted entirely for frozen sections. Three levels of each section submitted are examined and the results were compared with further levels on paraffin sections. Results: Overall 40% of patients (62/154) were found to be SLN positive on final (paraffin section) histology, out of which 44 demonstrated macrometastases (>2mm) and 18 micrometastases (<2mm). The overall sensitivity and specificity of frozen section analysis of SLN for the detection of macrometastasis was found to be 100% while those for micrometastasis were 33.3% and 100%, respectively. Moreover 20% of patients who had micrometastases in SLN had positive non-SLNs on final histology. Conclusions: Frozen section analysis of SLNs lacks sufficient accuracy to rule out micrometastasis by current protocols. Therefore these need to be revised in order to pick up micrometastasis which appears to have clinical significance. We suggest that this can be achieved by examining more step sections of blocks.