• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_2
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• pp.629-637
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• 2023

This study aimed to evaluate the effect of post-curing equipment and time on the flexural strength of 3D printing resins produced by a liquid crystal display(LCD) printer. The three 3D printing resins(DENTCA Denture Teeth, DT; C&B 5.0 hybrid, CH; C&B Permanent A2, CP) were divided into four groups according to post-curing time(10 min and 30 min) and equipment with or without vacuum treatment. For the three-point flexural strength test and biaxial strength test were prepared by method according to ISO 10477, ISO 6872, respectively. Flexural strength was measured with universal testing machine. Comparison between post-curing time of each post-curing equipment was analyzed by independent sample t-test and Mann-Whitney U test(α=.05), and comparison between groups according to each 3D printing resin was performed by Kruskal-Wallis test and post-hoc by Bonferroni-Dunn test(α=.05). The flexural strength of the resin post-curing under vacuum was higher than that of the resin post-curing in air. In the comparison according to the post-curing time, in the case of the post-curing equipment without vacuum, the 30 minute curing time showed significantly higher flexural strength than the 10 minute curing time, except for the biaxial flexural strength of CH(P<.05). In the post-curing equipment with vacuum, the three-point flexural strength of all 3D printing resins(DT, CH, and CP) showed a higher value at 30 minute curing time than at 10 minute curing time.

• The Journal of Korean Physical Therapy
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• v.29 no.3
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• pp.142-144
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• 2017

Purpose: Few studies have addressed the effect of diurnal circadian rhythms on postural stability, and thus the aim of the present study was to examine circadian effects on static and dynamic postural stability in young adults. Methods: Twenty-four subjects (9 men, 11 women: age=$22.20{\pm}1.77$, height=$167.20{\pm}10.47$, weight=$59.85{\pm}10.66$) from a university community volunteered for this study. Static and dynamic balance testing, which recorded using a Good Balance system (Good Balance, Metitur Ltd, Finland) was conducted at 9:00, 13:00, and 17:00 hours on two consecutive days, and the sequencing of static and dynamic balance tests were randomized. Results were analyzed using the non-parametric one-way repeated Friedman test in SPSS version 18.0 (SPSS Inc., Chicago, IL, USA), and variable found to be significant were subjected to Wilcoxon post hoc testing. Results: Static and dynamic balance showed significant difference at the three times assessments (test at 9:00, 13:00, and 17:00) during circadian. In the post hoc test of static (anteroposterior distance, mediolateral distance and COP (center of pressure) velocity) and dynamic balance (performance time), 13:00 was the longer and faster than 9:00. Conclusion: These results indicated that control of postural balance is influenced by diurnal circadian rhythms, and confirm that control of postural balance is more effective and better performance in the 09:00 hours than 13:00 hours or 17:00 hours.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.2_2
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• pp.389-395
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• 2024

The purpose of this study was to evaluate the effect of different washing solvents and washing methods on the flexural strength of 3D printed temporary resin. A bar(25 × 2 × 2 mm) was produced with a layer thickness of 50 ㎛ using an LCD-type 3D printer and divided into 15 groups(n = 10, each) according to washing solution(IPA; 99% isopropyl alcohol, TPM; 93% Tripropylene glycol monomethylether, ETL; Ethanol, TWC; Twin 3D Cleaner, and DNC; DIO navi Cleaner) and washing method(Dip; Dip washing, Ultra; Ultrasonic washing, and Auto; Automated washing). All groups were washed for 5 minutes, and post-cured for 5 minutes using a UV LED light curing machine. The Flexural strength was measured using a three-point bending test using a universal testing machine. For statistical analysis, one-way ANOVA, Tukey HSD post hoc test, Kruskal-Wallis test and post-hoc by Bonferroni-Dunn test(𝛼=.05) were performed depending on whether the normality test was satisfied. In all washing solvents except TPM and DNC, the Dip group showed the lowest flexural strength values, while the Auto group showed the highest flexural strength values except for DNC. Additionally, the washing solution showed completely different flexural strength values depending on the washing method.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.129-132
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• 2006

This study was to examine the relationship between golf participation level(frequency, duration, intensity) and sub-factors of social development, which are activity, stability, control, sociality, and autonomy. The population for the study were citizens who participated in golf at Daejeon city. 281 golf participants were selected through random sampling. The collected data were analyzed by t-test, One-way ANOVA, and post-hoc analysis. The results were as follows; First, there were differences in stability and sociality according to frequency of golf participation. Second, there were differences in activity, stability, and control according to duration of golf participation. Third, there were differences in activity, control, and sociality according to intensity of golf participation.

• The Journal of Korean Physical Therapy
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• v.30 no.2
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• pp.54-57
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• 2018

Purpose: Most studies have reported pain in the head-neck and upper-limbs according to smartphone usage, which is related to the proprioception sense in the head and neck, but there have been few studies. Therefore, the aim of this study was identify the adverse effects of the proprioceptive sense in the head-neck according to smartphone usage. Methods: Twenty-seven young adults (male: 9, female: 18) were enrolled in this study. The proprioceptive sense was measured through the joint reposition sense error and neural positon error in the head-neck during smartphone usage for 0, 5, and 20 minutes. The Noraxon MyoMotion system was used to record the joint position angle and neutral positon in the head-neck. One-way repeated ANOVA was used to identify the differences between the three smartphone use durations and the least-squares difference was used as a post hoc test. The data were analyzed using SPSS 18.0 software. Results: The joint reposition sense error and neural positon error in the head-neck were significantly different among the 0, 5, and 20 minutes of smartphone usage (p<0.05). In the post hoc test, the joint reposition sense error and neural positon error showed a significant difference between smartphone use for 0 minute and 5 minute, and between smartphone use for 0 minute and 20 minutes. Conclusion: This study suggests that smartphone use within 5 minutes can have adverse effects on the proprioceptive sense. Therefore, it is necessary to consider the appropriate use time and break time when using smart phones.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.1
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• pp.59-66
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• 2023

PURPOSE: This study examined the foot pressure distribution using the sprinter and skater patterns of coordinative locomotor training. METHODS: Thirty healthy adults, comprising 11 men and 19 women, participated in the study. All the participants performed patterns in sprinter pattern conditions 1-3 and skater pattern conditions 1-3, and were measured using a pedoscan to determine the applied foot pressure distribution. RESULTS: The participants significantly differed in the big toe during the sprinter pattern. As a result of the post hoc test, opposite and opposite sprinters showed a significant difference from the same sprinters (same sprinter; 21.33 ± 5.92, opposite sprinter; 23.54 ± 5.41, and reopposite sprinter; 24.14 ± 6.46). There was a significant difference in the lateral side during the skater pattern. As a result of the post hoc test, reopposite and same skaters showed a significant difference from opposite skaters (same skater; 49.88 ± 5.75, opposite skater; 48.78 ± 5.64, and reopposite skater; 51.15 ± 5.37). CONCLUSION: The foot pressure was distributed toward the hallux and fifth toe according to the sprinter and skater patterns of coordinative locomotor training.

• PNF and Movement
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• v.15 no.2
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• pp.141-148
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• 2017

Purpose: This study attempts to identify the effects of abdominal strength training using proprioceptive neuromuscular facilitation (PNF) on the balance ability and pain level of patients with chronic lower back pain. Methods: A total of 30 patients with chronic lower back pain were randomly divided into either experimental group I (n=10), who received abdominal strength training using PNF, experimental group II (n=10), who received abdominal strengthening training, or the control group (n=10), who received conventional physiotherapy. The interventions were applied three times a week for six weeks. We measured Berg's balance scale (BBS) in order to investigate the change in balance ability, while we measured the visible analogue scale (VAS) to determine the severity of pain. We conducted a paired t-test to compare the within-group change before and after the intervention. For the comparison of the between-group difference, we used a one-way ANOVA test. Tukey's test was used as a post hoc test. The statistical significance level was set at ${\alpha}=0.05$ for all the variables. Results: Experimental group I and experimental group II showed a significant within-group change in BBS (p<0.01). A statistically significant between-group difference was observed in terms of the change in BBS (p<0.01). According to the results of the post hoc Tukey test, experimental group I and experimental group II showed a more effective change in BBS than the control group. Experimental group I, experimental group II, and the control group all showed a significant within-group change in the VAS (p<0.01). There was a statistically significant between-group difference in terms of the change in the VAS (p<0.01). According to the results of the post hoc Tukey test, the change in the VAS was more effective in experimental group I than in experimental group II and the control group. Conclusion: In this study, the application of abdominal strength training using PNF for subjects who complained of chronic lower back pain proved effective in improving their balance ability and reducing pain. We therefore believe that this training method could be applied as a useful program for patients with chronic lower back pain.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.613-618
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• 2020

The average dose of Fast Low Dose C-arm CT used during hepatic arterial chemoembolization was compared with the average dose of DSA, and the exposure dose was analyzed by analyzing the average dose for each test technique in the total accumulated dose. 50 patients were randomly selected at our clinic and compared with Fast Low Dose C-arm CT, DAP and Air Kerma of DSA, and the accumulation of four test techniques (DSA, Fast Low Dose C-arm CT, Roadmap, Fluoroscopy) The proportion of dose (DAP, Air Kerma) was analyzed. For statistical comparative analysis, the corresponding sample T test and ANOVA test (post hoc test: Tukey) were performed using the statistical program SPSS 20.0. Fast Low Dose C-arm CT showed statistically significantly lower average dose (DAP, Air Kerma) than DSA. Reducing the number of tests for DSA can reduce the patient's exposure to medical radiation.

• The Journal of Korean Physical Therapy
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• v.18 no.4
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• pp.41-50
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• 2006

Purpose: The purpose of this study was to determined that the efficacy and comfort of iontophoretic transdermal delivery of lidocaine by comparison of local anesthetic duration, sensory threshold, pain threshold and pain tolerance levels according to four different cleansing regimes. Methods: Forty healthy volunteers were randomly assigned to four groups; oil cleansing group, lotion cleansing group, solution cleansing group and alcohol cleansing group. All subjects were received lidocaine iontophoresis on the forearm using direct current with 4 mA for 10 minutes. All subjects were measured the duration of local anesthesia after lidocaine iontophoresis, also evaluated the sensory threshold, pain threshold and pain tolerance level during iontophoresis. For comparisons of the efficacy and the sensory characteristics of iontophoresis within the groups, an one-way ANOVA was used. Results: The duration of local anesthesia were found significant difference between groups (p<0.001). The anesthetic duration in solution and alcohol cleansing groups were significantly longer than oil and lotion cleansing group by post hoc (p<0.05). Statistically significant difference were noted in respect to all sensory characteristics such as sensory threshold, pain threshold and pain tolerance between groups (p<0.001). The sensory threshold in solution and alcohol cleansing group were significantly lower than oil and lotion cleansing group by post hoc using Duncan multiple range test (p<0.05). The pain threshold and pain tolerance in solution and alcohol cleansing group were significantly higher than oil and lotion cleansing group by post hoc (p<0.05). Conclusion: These results demonstrated that cleansing regimes have affected the efficacy and discomfort of iontophoretic transdermal delivery of lidocaine. These findings indicate that cleansing agents without oil ingredient contributed to more comfort, and more successful achievement of the iontophoretic transdermal delivery.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.795-804
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• 2011

Purpose: The purpose of this study was to examine the effects of interactive pictorial education on community dwelling older Korean adults' self-efficacy and knowledge for safe medication. Methods: A quasi-experimental, three-group pre- and post-intervention design was used in this study. The interactive pictorial education was designed to suit the learning patterns and psychomotor skills of older adults. The education content, dealing with safe medication, was delivered over three sessions. A total of 136 older adults from local senior centers were assigned to one of the three groups: a) interactive pictorial education plus information booklet (experimental); b) education only with information booklet (conventional); or c) no intervention (control). Results: Participants receiving interactive pictorial education had significantly higher self-efficacy (F=24.32, p<.001) and knowledge (F=24.26, p<.001) scores than the information booklet or control group at post intervention. Post-hoc analyses indicated that both the interactive pictorial and the information booklet groups had significantly higher self-efficacy and knowledge scores than the control group at the post-test point (p<.05). Furthermore, the interactive pictorial group had higher self-efficacy and knowledge scores than the information booklet group at the post-test point (p<.05). Conclusion: These results suggest that the interactive pictorial education is an innovative approach that provides a means for older adults to learn appropriate medication use to improve their own health. It empowers older adults with different literacy levels to enhance their self-efficacy and knowledge for the safe use of medication.