• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.130-134
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• 1997

The structural defects, impurities, degree of crosslinking and shrinkage of 38 field-aged distribution cables have been analyzed. For the comparison of data, 9 new cables were also subjected to an analysis. It is observed that the structural defects and degree of crosslinking show a radial profile. The structural defects are different depending on the manufacturer. A large amount of impurities is present in the insulation shield, which hold true for the new cables manufactured recently. The degree of crosslinking near both shields is lower than that at the central region of the insulation layer. It was also found that, in some cal)toes, the ins난lation was not fully crosslinked. The shrinkage of field-aged cables is higher than that of new cables.

• Journal of the Korean institute of surface engineering
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• v.35 no.5
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• pp.289-294
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• 2002

ZnTe films have been grown on (100) GaAs substrate with two representative problems. The one is lattice mismatch, the other is thermal expansion coefficients mismatch of ZnTe /GaAs. It claims here, the relationship of film thickness and defects distribution with (100) ZnTe/GaAs using hot wall epitaxy (HWE) growth was investigated by transmission electron microscopy (TEM). It analyzed on the two-sort side using TEM with cross-sectional transmission electron microscopy (XTEM) and high-resolution electron microscopy (HREM). Investigation into the nature and behavior of dislocations with dependence-thickness in (100) ZnTe/ (100) GaAs hetero-structures grown by transmission electron microscopy (TEM). This defects range from interface to 0.7 $\mu\textrm{m}$ was high density, due to the large lattice mismatch and thermal expansion coefficients. The defects of low density was range 0.7$\mu\textrm{m}$~1.8$\mu\textrm{m}$. In the thicker range than 1.8$\mu\textrm{m}$ was measured hardly defects.

• Journal of IKEEE
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• v.18 no.2
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• pp.234-239
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• 2014

This paper proposes a new automatic detection method to inspect mura defects on display film surface using morphological image processing and labeling. This automatic detection method for mura defects on display films comprises 3 phases of preprocessing with morphological image processing, Gabor filtering, and labeling. Since distorted results could be obtained with the presence of non-uniform illumination, preprocessing step reduces illumination components using morphological image processing. In Gabor filtering, mura images are created with binary coded mura components using Gabor filters. Subsequently, labeling is a final phase of finding the mura defect area using the difference between large mura defects and values in the periphery. To evaluate the accuracy of the proposed detection method, detection rate was assessed by applying the method in 200 display film samples. As a result, the detection rate was high at about 95.5%. Moreover, the study was able to acquire reliable results using the Semu index for luminance mura in image quality inspection.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2783-2791
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• 2022

Molecular dynamics simulations were performed to predict the behavior of graphite atoms under neutron irradiation using large-scale atomic/molecular massively parallel simulator (LAMMPS) package with adaptive intermolecular reactive empirical bond order (AIREBOM) potential. Defect structures of graphite were compared with results from previous studies by means of density functional theory (DFT) calculations. The quantitative relation between primary knock-on atom (PKA) energy and irradiation damage on graphite was calculated. and the effect of PKA direction on the amount of defects is estimated by counting displaced atoms. Defects are classified into four groups: structural defects, energy defects, vacancies, and near-defect structures, where a structural defect is further subdivided into six types by decision tree method which is one of the supervised machine learning techniques.

• Archives of Plastic Surgery
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• v.50 no.1
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• pp.82-95
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• 2023

Upper extremity reconstruction may pose clinical challenges for surgeons due to the often-critical, complex functional demands of the damaged and/or missing structures. The advent of vascularized bone grafts (VBGs) has aided in reconstruction of upper extremity (UE) defects due to their superior regenerative properties compared with nonvascularized bone grafts, ability to reconstruct large bony defects, and multiple donor site options. VBGs may be pedicled or free transfers and have the potential for composite tissue transfers when bone and soft tissue are needed. This article provides a comprehensive up-to-date review of VBGs, the commonly reported donor sites, and their indications for the treatment of specific UE defects.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.72-81
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• 2023

This research proposes a novel approach to tackle the challenge of categorizing unstructured customer complaints in the automotive industry. The goal is to identify potential vehicle defects based on the findings of our algorithm, which can assist automakers in mitigating significant losses and reputational damage caused by mass claims. To achieve this goal, our model uses the Word2Vec method to analyze large volumes of unstructured customer complaint data from the National Highway Traffic Safety Administration (NHTSA). By developing a score dictionary for eight pre-selected criteria, our algorithm can efficiently categorize complaints and detect potential vehicle defects. By calculating the score of each complaint, our algorithm can identify patterns and correlations that can indicate potential defects in the vehicle. One of the key benefits of this approach is its ability to handle a large volume of unstructured data, which can be challenging for traditional methods. By using machine learning techniques, we can extract meaningful insights from customer complaints, which can help automakers prioritize and address potential defects before they become widespread issues. In conclusion, this research provides a promising approach to categorize unstructured customer complaints in the automotive industry and identify potential vehicle defects. By leveraging the power of machine learning, we can help automakers improve the quality of their products and enhance customer satisfaction. Further studies can build upon this approach to explore other potential applications and expand its scope to other industries.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.736-741
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• 2010

Purpose: Radical surgical extirpation in advanced breast cancer patients produces extensive loss of skin with large defects requiring plastic surgical procedures for the closure. Many reconstructive methods exist, the choice of which depends upon the characteristic of the wound, extent of resection and patient comorbidities. For adequate coverage of the large skin defects following resection of advanced breast cancer, current authors have performed a thoracoabdominal flap. Methods: From August 2008 to June 2009, 4 cases of thoraco-abdominal flap were performed for chest wall reconstruction after mastectomy of advanced breast cancer. Flap dissection was entirely performed in a subfascial plane and the flap involving the external oblique abdominal muscle. The flap was rotated clockwise in left chest wall defects and counterclockwise in right chest defects and the donor site was closed directly. Results: Their mean age, 55.7 years and the average follow-up interval was 9 months. Patients' oncologic status ranged from stage IIIc to stage IV, it was classified according to the TNM staging system. Flap dimensions ranged between $15{\times}15$ and $25{\times}25\;cm$. One flap sustained a partial loss at the distal margin and revision with pectoralis major musculocutaneous island flap. Conclusion: Large chest wall reconstructions are usually required after radical excision of advanced cancer stages patients with poor general conditions. Thoracoabdominal flap is a simple, quick single-stage procedure, and offer to patient fast recovery, low complication rate, enabling further concomitant adjuvant therapy.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.54-61
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• 1998

Free vascularized fibular is the most usuful bony donor of the long bone reconstruction in reconstructive microsurgical field. It has many benifits such as very strong strut tubular bone, very reliable vascular anatomy with large vascular diameter with long pedicle, minimal donor site morbity too. In that situations of the huge long bone defects in distal femur or proximal tibia, the defective bony shape and strength of the transplanted fibular bone is not enough if only one strut of the fibula is transfered. The bony circulation of the fibula has two ways, one from nutrient artery via peroneal artery through nutrient foramen which makes endosteal arterial network inside of the fibula, another way is periosteal network through outside encircling vascular network of the bone which distributed in muscle sleeves of the fibular diaphysis. Authors modified free vascularized fibular bone graft with transverse osteotomy is made from the anterolateral aspect of the fibular shaft just distal to entry of the nutrient artery. This produces two vascularized bone struts that may be folded pararell to each other but that remain connected by the periosteum and muscle cuff surrounding the peroneal artery and veins. The proximal strut is vascularized by both a periosteal and endosteal blood supply, whereas the distal strut is vascularized by a periosteal blood supply alone. This procedure can call "doule barrel" free vascularized fibular graft. We performed 7 cases of doule barrel fashined fibular transplantation on distal femur and proximal tibial large defects. Average bone union time takes 7 months from that procedure. There were no significant bone union time differences between both proximal and distal struts. After solid union of the transfered double barrel fibular graft, there were no stress fracture in our series. We can propose double barrel free vascualized fibular graft is usuful method in that cases with very large bone defect on large long bones especially metaphyseal defects.

• Archives of Plastic Surgery
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• v.41 no.2
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• pp.140-147
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• 2014

Background Epidermal cysts are commonly occurring masses usually less than 5 cm in diameter, but in predisposed patients, epidermal cysts can grow relatively large due to chronic infection. Methods From June 2002 to July 2010, 17 patients received 19 regional perforator-based island flaps to cover defects due to the excision of large epidermal cysts (diameter >5 cm) in the buttocks. Eight patients had diabetes, and seven had rheumatoid arthritis. The pedicles were not fully isolated to prevent spasms or twisting. Results All the flaps survived completely, except for one case with partial necrosis of the flap, which necessitated another perforator-based island flap for coverage. There were two cases of wound dehiscence, which were reclosed after meticulous debridement. There were no recurrences of the masses during follow-up periods of 8.1 months (range, 6-12 months). Conclusions In patients with large epidermal cysts and underlying medical disorders, regional perforator-based island flaps can be the solution to coverage of the defects after excision.

• Archives of Plastic Surgery
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• v.49 no.1
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• pp.39-42
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• 2022

Bilateral pectoralis major myocutaneous (PMMC) flaps are commonly used to reconstruct large chest wall defects. We report a case of large chest wall defect reconstruction using bilateral PMMC flaps augmented with axillary V-Y advancement rotation flaps for additional flap advancement. A 74-year-old male patient was operated on for recurrent glottic squamous cell carcinoma. Excision of the tumor resulted in a 10×10 cm defect in the anterior chest wall. Bilateral PMMC flaps were raised to cover the chest wall defect. For further flap advancement, V-Y rotation advancement flaps from both axillae were added to allow complete closure. All flaps survived completely, and postoperative shoulder abduction was not limited (100° on the right side and 92° on the left). Age-related skin redundancy in the axillae enabled the use of V-Y rotation advancement flaps without limitation of shoulder motion. Bilateral PMMC advancement flaps and the additional use of V-Y rotation advancement flaps from both axillae may be a useful reconstructive option for very large chest wall defects in older patients.