• Advances in materials Research
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• v.12 no.4
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• pp.273-286
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• 2023

The fracture mechanics make it possible to characterize the behavior with cracking of structures using parameters quantifiable in the sense of the engineer, in particular the stress field, the size of the crack, and the resistance to cracking of the material. Any structure contains defects, whether they were introduced during the production of the part (machining or molding defects for example). The aim of this work is to determine numerically by the finite element method the stress concentration factor Kt of a plate subjected to a tensile loading containing a lateral form defect with different sizes: a semicircle of different radii, a notch with different opening angles and a crack of different lengths. The crack propagation is then determined using the extended finite element technique (X-FEM). The modeling was carried out using the ABAQUS calculation code.

• Archives of Plastic Surgery
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• v.47 no.4
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• pp.340-346
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• 2020

Background Adipofascial flaps covered with a skin graft address the challenges involved in reconstructing dorsal foot defects. The purpose of this study was to describe a large adipofascial flap based on the perforators of the dorsalis pedis artery for large foot defects. Methods Twelve patients aged 5-18 years with large soft tissue defects of the dorsal foot due to trauma were treated with an extended dorsalis pedis adipofascial flap from May 2016 to December 2018. The flap was elevated from the non-injured half of the dorsum of the foot. Its length was increased by fascial extension from the medial or lateral foot fascia to the plantar fascia to cover the defect. All perforators of the dorsalis pedis artery were preserved to increase flap viability. The dorsalis pedis artery and its branches were kept intact. Results The right foot was affected in 10 patients, and the left foot in two patients. All flaps survived, providing an adequate contour and durable coverage with a thin flap. Follow-up lasted up to 2 years, and patients were satisfied with the results. They were able to wear shoes. Donor-site morbidity was negligible. Two cases each of partial skin graft loss and superficial necrosis at the tip of the donor cutaneous flap occurred and were healed by a dressing. Conclusions The hinged multiperforator-based extended dorsalis pedis adipofascial flap described herein is a suitable method for reconstructing dorsal foot defects, as it provides optimal functional and aesthetic outcomes with minimal donor site morbidity.

• Archives of Plastic Surgery
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• v.46 no.3
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• pp.255-261
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• 2019

Cross-leg flaps are a useful reconstructive option for complex lower limb defects when free flaps cannot be performed owing to vessel damage. We describe the use of the extended distally based sural artery flap in a cross-leg fashion for lower extremity coverage in three patients. To maximise the viability of these extended flaps, a delay was performed by raising them in a bipedicled fashion before gradual division of the tip over 5 to 7 days for cross-leg transfer. Rigid coupling of the lower limbs with external fixators was critical in preventing flap avulsion and to promote neovascular takeover. The pedicle was gradually divided over the ensuing 7 to 14 days before full flap inset and removal of the external fixators. In all three patients, the flaps survived with no complications and successful coverage of the critical defect was achieved. One patient developed a grade 2 pressure injury on his heel that resolved with conservative dressings. The donor sites and external fixator pin wounds healed well, with no functional morbidity. The cross-leg extended distally based sural artery flap is a reliable reconstructive option in challenging scenarios. Adequate flap delay, manoeuvres to reduce congestion, and postoperative rigid immobilization are key to a successful outcome.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.537-541
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• 2004

Molecular dynamics simulation of nanolithography by AFM is conducted to study nucleation of various defects, and their subsequent development and interactions as well. During nanolithography via AFM, dislocation loops are emitted along the top surface, and resourceful defect interactions such as, formation of voids chain via the motion of a jog, and creations of extended nodes and Lomer-Cottrell Lock are observed.

• Archives of Plastic Surgery
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• v.37 no.3
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• pp.277-280
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• 2010

Purpose: The resection of locally advanced or recurred breast cancers frequently result in large chest wall defects and it leads to a great challenges to cover. Generally simple skin grafts are not a practical option for patients because of their poor cosmetic appearance and prognosis. The latissimus dorsi and rectus abdominis musculocutaneous flap have traditionally been recommended for closure of these large defects. Though the cosmetic result of reconstruction using these flaps is often excellent, but has significant drawbacks. Therefore, we thought that chest wall reconstruction using the external oblique musculocutaneous flap can be an alternative method for extensive chest wall defect related to large, locally advanced breast carcinoma. Methods & Results: We present a case of a 50-year-old Korean female, refered to our department with a left breast tumor for 10 months. CT demonstrate a large tumor on the left anterior chest wall and multiple nodules of varying size in the cervical areas and liver. FDG-PET showed areas of hot uptake throughout the left chest wall, mediastinum and liver. Biopsy was consistent with invasive ductal carcinoma (Grade III). The initial tumor was considered inoperable, so a series of chemotherapy was initiated. Though the size of the breast mass was slightly decreased, the patient continued to suffer from purulent discharge, unpleasant odor and contact bleeding of the mass, the salvage mastectomy was performed. Conclusion: We could reconstruct $23{\times}16\;cm$ sized large chest wall defect, resulting from the resection of a locally advanced breast carcinoma, using an external oblique musculocutaneous flap successfully. Immediate postoperatively checked flap was healthy. Overall result was good without any significant complications and discharged 3 weeks after operation.

• Journal of Chest Surgery
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• v.37 no.10
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• pp.856-860
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• 2004

Interrupted aortic arch with concomitant intracardiac defects is a rare congenital anomaly that has an unfavorable natural course. We report a successful staged operation of interrupted aortic arch with apical muscular ventricular septal defect associating esophageal atresia with tracheoesophageal fistula in a 3-day-old neonate weighing 2.6 kg. We repaired esophageal atresia through the right thoracotomy and subsequently performed extended end-to-end anastomosis of the aortic arch with pulmonary artery banding through the left thoracotomy at same operation. The apical muscular VSD was repaired 87 day after first operation. The patient required multiple additional interventions before closure of the apical muscular ventricular septal defect, such as pyloromyotomy for idiopathic hypertrophic pyloric stenosis, anterior aortopexy for airway obstruction, and balloon aortoplasty for residual coarctation. She is now doing well.

• Journal of Chest Surgery
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• v.41 no.4
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• pp.476-479
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• 2008

The Rastelli operation has been a standard procedure for repairing complete transposition of the great arteries combined with a ventricular septal defect and pulmonary stenosis. Yet this procedure has several shortcomings, including the risk of incurring left ventricular outflow tract obstruction on long-term follow-up. In this regard, aortic translocation has recently been regarded as a potent alternative to Rastelli's operation. We report here on a case of complete transposition of the great arteries that was combined with an inlet-extended perimembranous ventricular septal defect and pulmonary stenosis in a 2-year-old boy. All the problems were successfully repaired using the aortic translocation technique. Postoperative echocardiography showed a straight and wide left ventricular outflow tract.

• The Journal of the Acoustical Society of Korea
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• v.30 no.1
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• pp.1-8
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• 2011

This paper presents a method for improving the performance of ISF coefficients quantizer through compensating the defect of the split structure vector quantization using the ordering property of ISF coefficients. And design the ISF coefficients quantizer for wideband speech codec using proposed method. The wideband speech codec uses split structure vector quantizer which could not use the correlation between ISF coefficients fully to reduce complexity and the size of codebook. The proposed algorithm uses the ordering property of ISF coefficients to overcome the defect. Using the ordering property, the codebook redundancy could be figured out. The codebook redundancy is replaced by the adaptive-extended codebook to improve the performance of the quantizer through using the ordering property, ISF coefficient prediction and interpolation of existing codebook. As a result, the proposed algorithm shows that the adaptive-extended codebook algorithm could get about 2 bit gains in comparison with the existing split structure ISF quantizer of AMR-WB (G.722.2) in the points of spectral distortion.

• Archives of Craniofacial Surgery
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• v.21 no.1
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• pp.35-40
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• 2020

Background: Extensive eyelid defects are extremely challenging to reconstruct. Although numerous procedures for reconstructing periorbital defects have been proposed, no method is universally used. However, the Tenzel flap is the most commonly used technique to reconstruct eyelid defects affecting one-third to two-thirds of the eyelid. Methods: Recognizing the usefulness of the Tenzel method, we adapted it to reconstruct larger defects around the eyes. Seven patients underwent reconstruction with a modified Tenzel flap with an extended concept after wide excision of a malignant skin lesion. The main difference from the conventional method is that the modified Tenzel flap includes the medial portion of the lower lid defect. The design of a modified Tenzel flap begins as a semicircle at the lateral canthal area, in the same way as a classical Tenzel flap, and extends medially along the subciliary line to cover the defect on the medial lower eyelid. The follow-up time ranged from 3 to 28 months. Results: All flaps survived and healed well, with minimal scarring and natural palpebral outlines. Conclusion: Compared to traditional procedures, the modified Tenzel flap has several advantages, including a one-stage operation, a less noticeable scar, and effective prevention of complications such as lower eyelid ectropion.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1377-1382
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• 1995

A high-resolution transmission electron microscopy study on the lattice defects formed in the high energy P ion implanted silicon was carried out on an atomic level. Results show that Lomer dislocations, 60$^{\circ}$perfect dislocations, 60$^{\circ}$ dislocation dipole and extrinsic stacking fault formed in the near Rp of as-implanted specimen. In the annelaed specimens, interstitial Frank loops, 60$^{\circ}$perfect disolations, 60$^{\circ}$dislocation dipoles, stacking faults, precipitates, perfect dislocation loops and <112> rodlike defects existed exclusively near in the Rp with various annealing temperature and time. From these results, it is concluded that extended secondary defects as well as the point defect clusters could be formed without annealing. Even at low temperature annealing such as 55$0^{\circ}C$, small interstitial Frank loops could be formed and precipitates were also formed by $700^{\circ}C$ annealing. The defect band annealed at 100$0^{\circ}C$ for 1 hr could be divided into two regions depending on the distribution of the secondary defects.