• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.3
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• pp.268-279
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• 2007

The reliability of cold-bonding repair technique of carbon-fiber reinforced plastics (CFRP) laminates, often used as a temporary repair for the airplane maintenance, has been evaluated during cyclic loading and localized heating by nondestructive methods. Major concern was given to the evolution of damage after repair in the form of delaminations due to localized heating and cyclic loading combined. An area of interest both on the specimen repaired by cold-bonding and the specimen without repair where delaminations were induced by localized heating and cyclic loading was monitored by acoustic emission (AE) testing and further examined by pitch-catch low-frequency bond testing, and pulse-echo high-frequency ultrasonic testing. The results showed that the reliability of cold-bonding repair would be significantly reduced by the localized heating and cyclic loading combined rather than by the cyclic loading only. AE monitoring appeared to be an effective and reliable tool to monitor the integrity of temporarily repaired CFRP laminates in terms of the structural health monitoring (SHM) philosophy.

• Journal of Korean Foot and Ankle Society
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• v.25 no.1
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• pp.17-24
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• 2021

Surgical treatments for chronic lateral ankle instability include anatomic repair, anatomic reconstruction using an auto or allograft, non-anatomic reconstruction, and arthroscopic repair. Open anatomic repair using the native ligament with or without reinforcement of the inferior extensor retinaculum is commonly performed in patients with sufficient ligament quality. Non-anatomical reconstruction using the adjacent peroneus brevis tendon is typically used only in patients with poor-quality ligament remnants or when previous repair failed. Anatomical reconstruction can be considered in patients in whom anatomical repair is expected to fail and when performed using auto or allografts can provide good to excellent short-term results, although the long-term outcomes of these methods remain unclear. Arthroscopic repair can provide good to excellent short-term clinical outcomes, but evidence supporting this technique is limited. The advantages and disadvantages of various surgical methods should be compared, and appropriate treatment should be implemented based on patient characteristics.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.763-769
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• 1996

A depressed alvelolar ridge and a collapsed interdental papilla in the anterior region may interfere with esthetic prosthodontic repair. The resultant sequelas will cause overcontoured prosthesis or dark shadow under pontic which may not suffice our patients' esthetic demands. So, surgical periodontal treatment has been needed for esthetic repair in deformed ridges and extensive interproximal spacing. Our treatment option alters Dr.Abram's roll technique to make palatally extended connective tissue secondary pedicle flap to obtain additonal connective tissue. Blood supply maintenance, least trauma, and no secondary wound is advantages in this modification.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.96-99
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• 2003

As arthroscopy is more advanced and the importance of meniscal function is more emphasized, there have been more advanced en meniscal repair technique. However conventional technique require the use of special instruments and extensive skin incision to protect the neurovasculatures and soft tissues. Also these have the potential problem of damage in articular surfaces by the knot. So, we develop a modified outside-in technique using spinal needles and nylon loops. Our method have many advantages not only in stability but simplicity, and there is no need of additional skin incision.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.6
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• pp.360-365
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• 2012

The simultaneous surgical correction of bilateral cleft lip and nasal deformity has become a more common surgical technique that has greatly changed conventional strategies for secondary nasal correction. Mulliken has been known as one of the earliest proponents for the synchronous repair of bilateral cleft lip and nasal deformity, and he emphasized the responsibility of the treating surgeon to evaluate nasolabial growth by comparing anthropometric measurements with age-matched normal patients. Good outcomes from this surgical method have been reported in clinical cases worldwide. Herein, we describe the management of two cases of bilateral cleft repair, following the principles and methods established by Mulliken. We also provide a relevant review of the literature.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.793-796
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• 2003

This study dealt with the manufacturing process of self-healing microcapsules for damage repair in polymeric composites. The microcapsule was consisted with a DCPD (dicyclopentadiene) as the healing agent and a urea-formaldehyde resin as the wall section. The size distribution of microcapsules were measured by a particle size analyzer using a laser diffraction technique. Thermal stability of microcapsules was investigated by using a TGA under continuous and isothermal heating conditions. According to the results, these microcapsules were verified to be to thermally stable and have a great potential to be applicable for damage repair in polymeric composites.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.04a
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• pp.173-181
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• 1997

To investigate the effects of haunch repair on the system seismic performance of steel moment-resisting frames (steel MRFs), a case study was conducted for a 13-story frame damaged during the 1994 Northridge earthquake. It was assumed that only those locations with reported damage would be repaired with haunches. A new analytical modeling technique for the dual panel zone developed by the author was incorporated in the analysis. Both the inelastic static and dynamic analyses did not indicate detrimental side effects resulting from the repair. As a result of the increased strength in dual panel zones, yielding in these locations were eliminated and larger plastic rotation demand occurred in the beams next to the shallow end of the haunches. Nevertheless, the beam plastic rotation demand produced by the Sylmar record of 1994 Northridge earthquake was still limited to 1.7% radians. The repair resulted in a minor increase in earthquake energy input. In the original structure, the panel zones should dissipate about 80%(for the Oxnard record) and 70%(for the Sylmar record) of the absorbed energy, assuming no brittle failure of moment connections. After repair, the energy dissipated in the panel zones and beams were about equal.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.2
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• pp.50-60
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• 1997

Reconfiguration of a memory array using spare rows and columns has been known to be a useful technique to improve the yield. When the numbers of spare rows and scolumns are limited, respectively, the repair problem is known to be NP-complete. In this paper, we propose the reconfiguration algorithm for an array of memory cells using faulty cel clustering, which removes rows and columns algrithm is the simplest reconfiguration method with the time complexity of $O(n^2)$, where n is the number of faulty cells, however the repair rate is very low. Whereas the exhaustive search algorithm has a high repair rate, but the time complexity is $O(2^n)$. The proposed algorithm provides the same repair rate as the exhaustive search algorithm for almost all cases and runs as fast as the greedy method. It has the time complexity of $O(n^3)$ in the worst case. We show that the propsed algorithm provides more efficient solutions than other algorithms using simulations.

• Advances in aircraft and spacecraft science
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• v.7 no.2
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• pp.151-168
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• 2020

The present study deals with the repair of composite structures by bonding composite patches. The composite structure is a carbon/epoxy laminate with stacking sequence [45/-45/0/90]S. The damaged zone is simulated by a central crack and repaired by bonding symmetrical composite patches. The repair is carried out using composite patches laminated from the same elemental folds as those of the cracked specimen. Three-dimensional finite element method is used to determine the energy release rate along the front of repaired crack. The effects of the repair technique used single or double patch, the stacking sequence of the cracked composite patch and the adhesive properties were highlighted on the variations of the fracture energy in mode I and mixed mode I + II loading.

• Corrosion Science and Technology
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• v.18 no.5
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• pp.190-195
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• 2019

SA508 low-alloy steel for a reactor vessel was exposed to primary water in a pressurized water reactor (PWR) plant because the cladding layer of type 309 stainless steel for the RPV was removed, due to an accident in which the detachment of the thermal sleeve occurred. The major advantage of the electrochemical deposition (ECD) Ni plating technique is that the reactor pressure vessel can be repaired without significant thermal effects, and Ni has solid corrosion resistance that can withstand boric acid. The corrosion rate assessment of the damaged part was performed, and its trend was analyzed. Essential variables of the Ni plating for repair of the damaged part were derived. These conditions are applicable variables for the repair plating device, and have been carefully adjusted using the repair plating device. The process for establishing ASME technical standards called Code Case N-840 is described. The process of developing Ni-plating devices, and the electroplating procedure specification (EPS) are described.