• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.1
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• pp.67-77
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• 2008

Seismic isolation has been studied continuously as a solution of the seismic engineering to reduce the sectional forces and the damages of structures caused by earthquakes. To certify reliable design and installation of the seismic isolation systems, seismic isolation bearings should be fabricated under well planned quality control process, and proper evaluation tests for their seismic performance should be followed. In this study, shear property evaluation tests for the lead rubber bearings(LRB) and the rubber bearings(RB) were implemented and the temperature dependency tests were also implemented to evaluate the changes of shear properties according to the changes of temperature. After evaluation tests, the measured shear properties were compared to their design values and their deviation was analyzed comparing with the allowable error ranges specified in Highway Bridge Design Specifications. These results showed that a considerable number of isolation bearings have so large deviations from their design values that their error ranges were over or very close to the allowable ranges. And the test results for temperature dependency showed that the shear properties of isolation bearings would be changed in great degree by the change of temperature during their service period. If these two types of changes in their shear properties are superposed, it would possible that the changes of shear properties from their original design values are over than 50%.

• 재활복지
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• v.20 no.1
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• pp.211-233
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• 2016

The purpose of this study is to figure out problems and to suggest improvement scheme by examining 31 of the disabled who used power wheelchair developed for safe moving and standing support. The results are as follows. First, standing power wheelchair that enables the disabled to sit and stand up was developed. It can also be used as means of transportation for moving in narrow space and in a short distance. In the usability test of this prototype, two groups were respectively examined in 60 evaluation items. One group consisted of 16 people with disabilities using manual wheelchairs. And the other one consisted of 15 people with disabilities using automatic wheelchairs. The entire average figure of two groups was shown to be 2.72 and standard deviation was 0.820. Specifically, the average figure of the group in manual wheelchair was 2.85 and the one of the other group in automatic wheelchair was 2.57. And both group replied that the move to stand up and sit on both types of wheelchair was the most inconvenient thing. It shows why ergonomic design for persons with under extremity disabilities to stand up and sit is needed. Second, with further study based on the results of usability test of the disabled, it will make contribution to increase the quality of people with disabilities by helping them move and do daily lives on their own.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.471-480
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• 2019

L-spine 3~4, L-spine 4~5, and L-spine 5~Sacrum 1 intervertebral disc(IVD) angle according to gender, age, body mass index(BMI), lumbar lordosis angle(LLA) were compared and analyzed. The anteriorposterior incidence angle of L-spine 3 ~ 4, L-spine 4 ~ 5 and L-spine 5~Sacrum 1 in body mass index were 5.66, 13.23 and 29.13 degrees in the head direction and L-spine 3 4, L-spine 4 ~ 5, L-spine 5~Sacrum 1 had 6.32 degrees, 16.09 degrees and 35.36 degrees in the head direction. The distortion area ratio comparison was performed with the phantom image using the proposed incidence angle. There was a significant difference in L-spine 4~5 and L-spine 5~Sacrum 1 IVD angle relative to body mass index and LLA(p<0.05), IVD angle and LLA were positively correlated(p<0.05).As a result of evaluating the usefulness of the image by applying the incidence angles of the disc angles according to the phantom angle of deviation to the head direction as 11 degrees for L4 and 26 degrees for L5, the distortion ratio area decreased from 14.90% to 12.11% in L4, And from 15.25% to 13.72% in L5. In anteriorposterior image of the Lumbar spine applying the incidence angle according to the measured disc angle, it is possible to reduce the distortion to purpose L4, L5. And improved the quality and diagnostic information of the target site.

• Progress in Medical Physics
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• v.30 no.1
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• pp.14-21
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• 2019

Purpose: To report the initial experience of patient-specific quality assurance (pQA) for the wobbling and line-scanning proton therapy at Samsung Medical Center. Materials and Methods: The pQA results of 89 wobbling treatments with 227 fields and 44 line-scanning treatments with 118 fields were analyzed from December 2015 to June 2016. For the wobbling method, proton range and spread-out Bragg peak (SOBP) width were verified. For the line-scanning method, output and two-dimensional dose distribution at multiple depths were verified by gamma analysis with 3%/3 mm criterion. Results: The average range difference was -0.44 mm with a standard deviation (SD) of 1.64 mm and 0.1 mm with an SD of 0.53 mm for the small and middle wobbling radii, respectively. For the line-scanning method, the output difference was within ${\pm}3%$. The gamma passing rates were over 95% with 3%/3 mm criterion for all depths. Conclusions: For the wobbling method, proton range and SOBP width were within the tolerance levels. For the line-scanning method, the output and two-dimensional dose distribution showed excellent agreement with the treatment plans.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.317-324
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• 2019

The purpose of this study is to find how the childcare teacher aptitude of students majoring in childcare and education influences their perception of teacher professionalism. To achieve that, a questionnaire survey was conducted with 216 early childhood preservice teachers living in A city. For data processing and analysis, SPSS program was used so as to conduct frequency analysis and calculate the mean and standard deviation. In addition, to test reliability and find relations between variables, Cronbach's ${\alpha}$, correlation analysis, and multiple regression analysis were conducted. As a result, firstly, in terms of the childcare teacher aptitude perceived by the students majoring in childcare and education, they highly perceived an affinity with young children and a sense of calling of their job; in terms of their perception of teacher professionalism, they highly perceived social necessity and vocational ethics. Secondly, early childhood preservice teachers' childcare teacher aptitude had a statistically significant correlation with their perception of teacher professionalism. Thirdly, the sub factors of early childhood preservice teachers' childcare teacher aptitude all positively influenced the sub factors of the perception of teacher professionalism. Given the study results, the students majoring in childcare and education perceived the importance of their aptitude of childcare teacher. In order to provide high-quality childcare service and create the positive aptitude of childcare teacher, it will be necessary to conduct a variety of basic research.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.1
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• pp.60-72
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• 2021

Objectives: This study was performed to investigate the level of participation in and satisfaction with training courses at job training institutions and to improve participation and satisfaction through changes in the training method for industrial ventilation subjects. Methods: The results were analyzed for the mean and standard deviation by t-test and ANOVA, (p=0.05). Participation rates were examined for three courses: specialization, job training, and supervisory. The participation inthe education was 428 people, and the result of satisfaction with the change of education method was 878 people. Satisfaction was investigated for the specialized curriculum and job training curriculum,but not the supervisor curriculum. The satisfaction results for six items(contents, quality, skill, level, degree of understanding, degree of practical) were analyzed according to the change in the training medium and the method among people in one occupational ventilation subject. Results: The participation rate was similar in the job training and specialized training courses, but the lowest rate was in supervisory courses(p=0.05). In general, there was the lowest participation on the first day of education, and the participation rate improved after the second day. Satisfaction with the course was high for the specialized education course with a number of practical education assignments(p=0.278). The satisfaction level for the teaching method in the industrial ventilation subjects was high in a mixed group which combined lecture and practice. The industrial ventilation course in the basic job training course showed a difference between lecture and mixed education(p=0.111), but there was no significant difference. However, the industrial ventilation course in the advance job training course showed a clear difference between lecture and the mixed education(p=0.036). Conclusions: Therefore, the first day of training should start in the afternoon so that more trainees can participate, and it is recommended to assign important subjects after two days. In addition, it is suggested that job competency-enhancing education utilize various educational methods and media.

• 한국노년학
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• v.28 no.4
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• pp.1089-1111
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• 2008

The purpose of this study was to research the effects of socio-demographic factors and values in each group on satisfaction with life by categorizing the activity types of the elderly into volunteer work and economic activities. The subjects of this study were 60 years an old higher. The questionnaires were categorized depending on activity types and collected. The voluntary work group consisted of 201 people (76 males, 36.8% and 125 females, 62.2%), The economic activity group consisted of 219 people (127 males, 58.0% and 92 females, 42.0%). The SPSS 14.0 Windows program was used to analyze data. Frequency, average, standard deviation, factor analysis, Pearson correlation coefficient, t-test, One-Way ANOVA analysis, and hierarchical multiple linear regression were analyzed. The major findings of this study indicate that the elderly in the voluntary work group have a high collectivism value, higher income earned by performing economic activities, and good cognitive health affected by a high satisfaction with life. From these research results, it was proved that a collectivism value is a common factor that affects satisfaction with life in both of the economic activity group. Those who were older had a traditional collectivism value. The voluntary work group showed a stronger collectivism value and higher satisfaction with life than the economic activity group. Thus, the diverse types of voluntary work should be developed and a systematic system should be established as methods for improving quality of life and satisfaction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.713-718
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• 2021

This study was conducted to clarify the role and importance of dental hygienists in improving patient satisfaction in dental medical institutions, and to improve the social position, working conditions, and environment of dental hygienists. This study evaluated the impact of dental hygienists on dental satisfaction, revisits, and doctor recommendations for patients who had received prosthodontic treatment at dentistry in the last 10 years. This study analyzed the data from 166 survey questionnaires from June 1, to July 2, 2020. For data analysis, the SPSS Ver 23.0 program was used to calculate frequency and percentage, mean and standard deviation of the variables, Pearson correlation analysis, and multiple regression analysis. As a result, the average quality of medical services provided by dental hygienists among prosthetics was 4.05, the average dental satisfaction was 4.27, the average revisit was 3.97, and the average recommendation was 4.01. As a result of Pearson's correlation analysis, there was a significant positive correlation between each variable (P<0.01). As a result of multiple regression analysis, the level of knowledge appeared as a factor affecting dental satisfaction (P<0.05). The factors influencing both the revisits and the intention to recommend were the level of knowledge and the level of education (P<0.05).

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1615-1627
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• 2020

The purpose of this study is to compare and analyze the performance of KOMPSAT-3 Digital Surface Model (DSM) made in overseas testbed area. To that end, we collected the KOMPSAT-3 in-track stereo image taken in San Francisco, the U.S. The stereo geometry elements (B/H, converse angle, etc.) of the stereo image taken were all found to be in the stable range. By applying precise sensor modeling using Ground Control Point (GCP) and DSM automatic generation technique, DSM with 1 m resolution was produced. Reference materials for evaluation and calibration are ground points with accuracy within 0.01 m from Compass Data Inc., 1 m resolution Elevation 1-DSM produced by Airbus. The precision sensor modeling accuracy of KOMPSAT-3 was within 0.5 m (RMSE) in horizontal and vertical directions. When the difference map was written between the generated DSM and the reference DSM, the mean and standard deviation were 0.61 m and 5.25 m respectively, but in some areas, they showed a large difference of more than 100 m. These areas appeared mainly in closed areas where high-rise buildings were concentrated. If KOMPSAT-3 tri-stereo images are used and various post-processing techniques are developed, it will be possible to produce DSM with more improved quality.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.281-288
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• 2021

This study was conducted to analyze and compare the concentrations of heavy metals in 430 different products of 20 types of herbal medicines available in the domestic market in Korea by Graphite Furnace-Atomic Absorption Spectrometry (GF-AAS) and automated mercury analyzer. The accuracy for lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) was in the range 92.67-102.56%, and the precision was 0.21-6.00 relative standard deviation (RSD%), which was in compliance with the Codex acceptable range. Furthermore, the Food Analysis Performance Assessment Scheme (FAPAS) quality control (QC) material showed a recovery range of 96.7-102.0% and 0.33-4.93 RSD%. The average contents (㎍/kg) of Pb, As, Cd, and Hg in herbal medicines were 254.9 (not detected (N.D.)-2,515.2), 171.0 (N.D.-2,465.2), 99.2 (N.D.-797.1), and 6.0 (N.D.-83.6), respectively. Based on the quantitative analysis results, the heavy metal contents of 20 types of herbal medicines distributed in Korea are within the acceptable range according to the standards issued by the Ministry of Food and Drug Safety (MFDS). By using the manufacturer of herbal products as the standard for QC, the Pb, As, Cd, and Hg contents were investigated in the packaging process just before distribution to determine the actual conditions of residual heavy metals in herbal medicines. Thus, these result may contribute to monitoring the QC of herbal medicines distributed in Korea and could provide basic data for supplying safe herbal medicines to the public.