• International Journal of Precision Engineering and Manufacturing
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• v.2 no.3
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• pp.5-10
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• 2001

Due to the development of high-strength fibers and adhesives, it is now possible to repair cracked metallic plates by bonding reinforced patches to the plate over the crack. In this study, pre-cracked aluminum 6061-T6 alloy plates repaired with bonded carbon/epoxy composite patch are applied to investigate the effect of various patch shapes on the tensile strength and the fatigue behavior of the structure. A non-patch-boned cased and 2 type-50$\times$50, 40$\times$20 mm-composite patch-bonded cases were tested to obtain fracture loads and fatigue crack growth rate. The results showed that the patch-bonded repair improves the static strength by 17% and the fatigue life by 200% compared to non-repaired case. It means that patch-boned repair is more effective in the fatigue life. It was also revealed that the patching method along crack growth direction is more efficient in cost and weight reduction. By observing the fractography, patch-bonded repair specimens demonstrated zigzag fracture patterns compared with the non-patched specimens, which shows a typical ductile fracture.

• Advances in pediatric surgery
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• v.17 no.1
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• pp.58-64
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• 2011

Minimally invasive techniques for pediatric inguinal hernia repair have been evolving in recent years. We applied the laparoscopic method to repair pediatric inguinal hernia using the techniques of sac transection and intra-corporeal ligation. Between November 2008 and August 2010, 67 pediatric patients (47 boys and 20 girls) with inguinal hernias were included in this study. Postoperative activities, pain, and complication were checked prospectively at regular follow-up. One patient presented with clinically bilateral hernia, and three patients had metachronous hernias. Thirty-two cases out of 63 patients with unilateral hernias had a patent processus vaginalis on the contralateral side. Mean operation time was $35{\pm}11.4$ minutes for unilateral hernias and $43{\pm}11$ minutes for bilateral hernias. There were no intra-operative complications. One patient had a small hematoma on the groin postoperatively, which subsided spontaneously in a week. Recurrence and metachronous hernia were not found at follow up. In summary, laparoscopic inguinal repair in children is safe, easy to perform and has an additional advantage of contralateral exploration. Further studies should include long term follow-up.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.127-128
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• 2017

Tests are conducted according to the ISO TS 16774, Part 3 standard for quality management of leakage repair materials used in cracks in underground concrete structures. These test methods are performed indirectly using a nonwoven fabric on a chalet containing leak repair materials. However, it is considered that it is appropriate to verify the resistance of the repair material, which is required to be applied directly to the cracks in the actual field and to exhibit the resistance of the flow velocity. In this study, mass change was measured by using nonwoven fabric and nonwoven fabric. As a result, both methods showed an increase in mass, which indicated that the maintenance material itself contained a large amount of water, and that the mass change occurred depending on the drying state. Also, depending on the use of nonwoven fabric, the error due to the indirect test could not be ruled out. Therefore, further verification is needed, and it is considered that the test for change of mass reduction measurement is necessary according to the drying time of other types of the same series.

• Journal of Welding and Joining
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• v.33 no.1
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• pp.87-93
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• 2015

This study was performed to develop repair technology for J-Groove dissimilar metal weld of pressurizer heater sleeve in nuclear power plants. Pad, J-Groove automatic welding and mechanical machining equipments to develop repair technology using 'Half Nozzle Repair' were designed and manufactured. To obtain the optimum welding process parameters during Pad temperbead overlay welding, several welding experiments using Taguchi method were conducted. Weldability of Pad overlay weld specimens was estimated by PT/RT test, FE-SEM, EDS and Vickers hardness test. Also, J-Groove welding to adjust weld shape conditions requiring in ASME Code was carried out and its integrity of weld specimens was evaluated through PT/RT test and optical microscope. Consequently, it was revealed that Pad and J-Groove overlay welding for dissimilar metal weld of pressurizer heater sleeve could be possible to meet Code standard without weld defect.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.108-113
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• 2005

The damageability and repairability of similar platform type vehicles could be very concerned with design optimization. In all the vehicles crash tested, small size passenger vehicles were weakness in aspect of damageability and repairability. The most critical area appears to be repair cost considering that parts cost is the largest portion of total repair cost segments. Besides repair cost, attaching method of front sidemember and subframe are placed special importance for impact energy absorption and damageability and repairability. So in order to improve damageability and repairability of vehicle structure and body component of the monocoque type passenger vehicles, the end of front side member and front back beam should be designed with optimum level and to supply the end of front side member as a partial condition approx 300mm. The effectiveness of design concept on the 40% offset frontal impact characteristics of the passenger vehicle structure is investigated and summarized.

• Journal of the Korean Institute of Educational Facilities
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• v.25 no.1
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• pp.3-12
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• 2018

Educational facilities are more uncertain about maintenance costs due to their comprehensive and long life-cycle compared to commercial buildings. In addition, maintenance of the existing post management system can not maintain the original function of education facilities continuously and economically. In order to overcome this problem, it is necessary to analyze the repair and replacement cost for the uncertainty factor in maintenance. This study propose a model to determine repair and maintenance cost and cycle of educational facility based on probabilistic estimation concept. For the analysis, Monte Carlo simulation, a probabilistic analysis method, was applied based on the repair and maintenance history data of the educational facilities in Florida. The results of this study can be used as a guideline for quantitative facility management and facility management research.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.374-384
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• 2018

This study examined the effects of clarification training on conversational breakdowns and repair strategies of 3 school aged children with ASD. Clarification training provided to the participants during playing the barrier games. The results found that the occurrence of conversational breakdown was decreased in terms of overall and types. The occurrence and appropriateness rates of repair strategies were increased among all participants. Based on the results, 'clarification training' used in this study can be an effective method to train children with ASD for appropriate repair strategies in conversation.

• Journal of Chest Surgery
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• v.49 no.1
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• pp.35-38
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• 2016

The management of recurrent tricuspid regurgitation after tricuspid valve repair in patients with Ebstein anomaly is difficult, and tricuspid valve replacement is most commonly performed in such patients. We report two cases of recurrent tricuspid regurgitation in patients with Ebstein anomaly that were successfully re-repaired using the cone technique. The cone repair technique is a useful surgical method for reconstructing a competent tricuspid valve, and can be applied in patients who have undergone previous tricuspid valve repair.

• The Journal of Korean Physical Therapy
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• v.33 no.2
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• pp.114-121
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• 2021

Purpose: This study examined the effects of therapeutic massage (TMP) and home exercise program (HEP) on pain, range of motion (ROM), depression, and quality of life (QOL) after arthroscopic rotator cuff repair in middle-aged women. Methods: Nineteen middle-aged women who underwent arthroscopic rotator cuff repair were enrolled in the study. All subjects were assigned randomly to the experimental group (n=9) or the control group (n=10). The subjects in both groups performed HEP for 30 minutes, three times per day, for eight weeks. The subjects in the experimental group also performed HEP, with TMP being performed for 30 minutes, 16 sessions for eight weeks. All subjects were evaluated with a visual analogue scale (VAS), shoulder ROM, self-rating depression scale (SDS), and Korean brief version of WHO quality of life scale (WHOQOL-BREF). A paired t-test was performed to test the significant differences between before and after the intervention. An independent t-test was conducted to test the significant differences between the groups. Results: Following the intervention, both groups showed significant differences than before the intervention in the VAS, shoulder ROM, SDS, and WHOQOL-BREF (p<0.05). There were significant differences in the ROM of shoulder flexion, SDS, and WHOQOL-BREF between the groups (p<0.05). Conclusion: These findings suggest that intensive TMP is an effective method for improving shoulder flexion mobility, depressive symptom, and QOL in middle-aged women after arthroscopic rotator cuff repair.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.47-48
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• 2023

Reinforced concrete structures are an integrated structure in which reinforcing bars are placed on the tensile side of the beam to compensate for concrete that is strong in compression but weak in tension, so that the concrete receives compressive force and the reinforcing bars receive tensile force. It is durable, fire-resistant, economical, and adapts to the shape and dimensions of the structure. It has been widely used for a long time because it can be made freely without restrictions. However, reinforced concrete structures have the disadvantage that cracks occur easily, so they are repaired using a cross-sectional construction method. During this process, problems such as the repair part falling off occurred, so in order to solve the problem, stress changes due to changes in the size of the repair part were examined. As a result, based on the elastic modulus ratio of 1.0, the stress tended to increase as the size of the repair part decreased when it was less than 1.0, and the opposite tendency was seen when it was more than 1.0. This is believed to be due to an increase in the area of the part with a large elastic modulus.