• Title/Summary/Keyword: Large defects

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Sequential Defect Detection According to Defect Possibility in TFT-LCD Panel Image (TFT-LCD 패널 영상에서 결함 가능성에 따른 순차적 결함 검출)

  • Lee, SeungMin;Kim, Tae-Hun;Park, Kil-Houm
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.4
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    • pp.123-130
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    • 2014
  • In TFT-LCD panel images, defects are typically detected by using a large difference in the brightness compared to the background. In this paper, we propose a sequential defect detection algorithm according to defect possibility caused by difference of brightness. By using this method, pixels with high defect probabilities are preferentially detected and defects with a large brightness difference are accurately detected. Also, limited defects with a small brightness difference is detected more reliably, eventually minimizing the degree of over-detection. We have experimentally confirmed that our proposed method showed an excellent detection result for detecting limited defects as well as defects with a large brightness difference.

Vascularized bone grafts for post-traumatic defects in the upper extremity

  • Petrella, Giovanna;Tosi, Daniele;Pantaleoni, Filippo;Adani, Roberto
    • Archives of Plastic Surgery
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    • v.48 no.1
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    • pp.84-90
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    • 2021
  • Vascularized bone grafts (VBGs) are widely employed to reconstruct upper extremity bone defects. Conventional bone grafting is generally used to treat defects smaller than 5-6 cm, when tissue vascularization is adequate and there is no infection risk. Vascularized fibular grafts (VFGs) are mainly used in the humerus, radius or ulna in cases of persistent non-union where traditional bone grafting has failed or for bone defects larger than 6 cm. Furthermore, VFGs are considered to be the standard treatment for large bone defects located in the radius, ulna and humerus and enable the reconstruction of soft-tissue loss, as VFGs can be harvested as osteocutaneous flaps. VBGs enable one-stage surgical reconstruction and are highly infection-resistant because of their autonomous vascularization. A vascularized medial femoral condyle (VFMC) free flap can be used to treat small defects and non-unions in the upper extremity. Relative contraindications to these procedures are diabetes, immunosuppression, chronic infections, alcohol, tobacco, drug abuse and obesity. The aim of our study was to illustrate the use of VFGs to treat large post-traumatic bone defects and osteomyelitis located in the upper extremity. Moreover, the use of VFMC autografts is presented.

Surgical Considerations of One-Stage Reconstruction of Large Extremity Defects Using a Thin Deep Inferior Epigastric Perforator Flap

  • Seung Yeol Lee;Moon Chul Seok;Bo Young Park
    • Archives of Plastic Surgery
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    • v.50 no.6
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    • pp.586-592
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    • 2023
  • Background One-stage reconstruction with "thin perforator flaps" has been attempted to salvage limbs and restore function. The deep inferior epigastric perforator (DIEP) flap is a commonly utilized flap in breast reconstruction (BR). The purpose of this study is to present the versatility of DIEP flaps for the reconstruction of large defects of the extremities. Methods Patients with large tissue defects on extremities who were treated with thin DIEP flaps from January 2016 to January 2018 were included. They were minimally followed up for 36 months. We analyzed the etiology and location of the soft tissue defect, flap design, anastomosis type, outcome, and complications. We also considered the technical differences in the DIEP flap between breast and extremity reconstruction. Results Overall, six free DIEP flaps were included in the study. The flap size ranged from 15 × 12 to 30 × 16 cm2. All flaps were transversely designed similar to a traditional BR design. Three flaps were elevated with two perforators. Primary closure of the donor site was possible in all cases. Five flaps survived with no complications. However, partial necrosis occurred in one flap. Conclusion A DIEP flap is not the first choice for soft tissue defects, but it should be considered for one-stage reconstruction of large defects when the circulation zone of the DIEP flap is considered. In addition, this flap has many advantages over other flaps such as provision of the largest skin paddle, low donor site morbidity with a concealed scar, versatile supercharging technique, and a long pedicle.

Part tolerancing through multicale defect analysis

  • Petitcuenot, Mathieu;Anselmetti, Bernard
    • International Journal of Aeronautical and Space Sciences
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    • v.17 no.1
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    • pp.109-119
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    • 2016
  • When manufactured parts undergo large deformations during the manufacturing process, the global specifications of a part based on the concept of tolerance zone defined in the ISO 1101 standard [1] enable one to control the part's global defects. However, the extent of this tolerance zone is too large when the objective is to minimize local defects, such as hollows and bumps. Therefore, it is necessary to address local defects and global defects separately. This paper refers to the ISO 10579 standard [2] for flexible parts, which enables us to define a stressed state in order to measure the part by straightening it to simulate its position in the mechanism. The originality of this approach is that the straightening operation is performed numerically by calculating the displacement of a cloud of points. The results lead to a quantification of the global defects through various simple models and enable us to extract local defects. The outcome is an acceptable tolerance solution. The procedure is first developed for the simple example of a steel bar with a rectangular cross section, then applied to an industrial case involving a complex 3D surface of a turbine blade. The specification is described through ISO standards both in the free state and in the straightened state.

Fabrication of Large Area Photonic Crystals with Periodic Defects by One-Step Holographic Lithography

  • Ma, Jie;Wong, Kam Sing;Li, Shan;Chen, Zhe;Zhou, Jianying;Zhong, Yongchun
    • Journal of the Optical Society of Korea
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    • v.19 no.1
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    • pp.63-68
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    • 2015
  • A one-step fabrication of a photonic crystal (PC) with functional defects is demonstrated. Using multi-beam phase-controlled holographic lithography with a diffracting optical element, large area one dimensional (1D) and two dimensional (2D) PCs with periodic defects were fabricated. The uniform area is up to $2mm^2$, and tens of defect channels have been introduced in the 1D and 2D PC structure. This technique gives rise to substantial reduction in the fabrication complexity and significant improvement in the spatial accuracy of introducing functional defects in photonic crystals. This method can also be used to design and fabricate three dimensional (3D) PCs with periodic defects.

Proximally based sural artery flap for the reconstruction of soft tissue defects around the knee and proximal third of the leg in India: a clinical study

  • Palukuri Lakshmi;Sreedharala Srinivas;Dharmapuri Madhulika;Sanujit Pawde;Ajo Sebastian;Swathi Sankar;Sandeep Reddy Chintha
    • Journal of Trauma and Injury
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    • v.36 no.4
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    • pp.369-375
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    • 2023
  • Purpose: The reconstruction of defects around the knee and the proximal third of the leg necessitates thin, pliable skin with a stable and sensate soft tissue cover. This study analyzed the use of a proximally based sural artery flap for the coverage of such defects. Methods: This prospective clinical interventional study involved 10 patients who had soft tissue defects over the knee and the proximal third of the leg. These patients underwent reconstruction with a proximally based sural artery flap. The study analyzed various factors including age, sex, etiology, location and presentation of the defect, defect dimensions, flap particulars, postoperative complications, and follow-up. Results: There were 10 cases, all of which involved men aged 20 to 65 years. The most common cause of injury was trauma resulting from road traffic accidents. The majority of defects were found in the proximal third of the leg, particularly on the anterolateral aspect. Defect dimensions varied from 6×3 to 15×13 cm2, and extensive defects as large as 16 cm×14 cm could be covered using this flap. The size of the flaps ranged from 7×4 to 16×14 cm2, and the pedicle length was 10 to 15 cm. In all cases, donor site closure was achieved with split skin grafting. This flap consistently provided a thin, pliable, stable, and durable soft tissue cover over the defect with no functional deficit and minimal donor site morbidity. Complications, including distal flap necrosis and donor site graft loss, were observed in two cases. Conclusions: The proximally based sural fasciocutaneous flap serves as the primary method for reconstructing medium to large soft tissue defects around the knee and the proximal third of the leg. This technique offers thin, reliable, sensate, and stable soft tissue coverage, and can cover larger defects with minimal complications.

Development and Utilization of Manufacturing Technique for Large Steel Casting (대형 주강품의 제조기술 개발과 실용화)

  • Tsumura, Osamu;Yoshimoto, Kazuo;Yamakuro, Sigeru
    • Journal of Korea Foundry Society
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    • v.24 no.2
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    • pp.63-70
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    • 2004
  • Foundry techniquews for large steel casting depends on the skills of foundrymen considerably. Especially, the problem of reducing casring surface defects is difficult to clear numerically. Statistical analysis by using wuantification theory for hot tear and sand inclusion, and multiple regression analysis for dimensional defects have been shown to be examples of solving this difficulty. Many causes of surface defects can be evaluated by these analyses. These evaluations serve as the base data of defect reduction and contribute to the constant improvement of casting quality and quality enhancement activity. The system to perform quality enhancement activity was developed and it proved very useful for transfering foundry techniques and skills from the old to young generations.

Use of the Anterolateral Thigh and Vertical Rectus Abdominis Musculocutaneous Flaps as Utility Flaps in Reconstructing Large Groin Defects

  • Aslim, Edwin Jonathan;Rasheed, Mohamed Zulfikar;Lin, Fangbo;Ong, Yee-Siang;Tan, Bien-Keem
    • Archives of Plastic Surgery
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    • v.41 no.5
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    • pp.556-561
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    • 2014
  • Background Groin dissections result in large wounds with exposed femoral vessels requiring soft tissue coverage, and the reconstructive options are diverse. In this study we reviewed our experience with the use of the pedicled anterolateral thigh and vertical rectus abdominis musculocutaneous flaps in the reconstruction of large groin wounds. Methods Groin reconstructions performed over a period of 10 years were evaluated, with a mean follow up of two years. We included all cases with large or complex (involving perineum) defects, which were reconstructed with the pedicled anterolateral thigh musculocutaneous or the vertical rectus abdominis musculocutaneous (VRAM) flaps. Smaller wounds which were covered with skin grafts, locally based flaps and pedicled muscle flaps were excluded. Results Twenty-three reconstructions were performed for large or complex groin defects, utilising the anterolateral thigh (n=10) and the vertical rectus abdominis (n=13) pedicled musculocutaneous flaps. Femoral vein reconstruction with a prosthetic graft was required in one patient, and a combination flap (VRAM and gracilis muscle flap) was performed in another. Satisfactory coverage was achieved in all cases without major complications. No free flaps were used in our series. Conclusions The anterolateral thigh and vertical rectus abdominis pedicled musculocutaneous flaps yielded consistent results with little morbidity in the reconstruction of large and complex groin defects. A combination of flaps can be used in cases requiring extensive cover.

Microsurgical reconstruction of posttraumatic large soft tissue defects on face (광범위한 안면외상 환자에서의 미세술기를 이용한 재건술)

  • Baek, Wooyeol;Song, Seung Yong;Roh, Tai Suk;Lee, Won Jai
    • Journal of the Korean Medical Association
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    • v.61 no.12
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    • pp.724-731
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    • 2018
  • Our faces can express a remarkable range of subtle emotions and silent messages. Because the face is so essential for complex social interactions that are part of our everyday lives, aesthetic repair and restoration of function are an important tasks that we must not take lightly. Soft-tissue defects occur in trauma patients and require thorough evaluation, planning, and surgical treatment to achieve optimal functional and aesthetic outcomes, while minimizing the risk of complications. Recognizing the full nature of the injury and developing a logical treatment plan help determine whether there will be future aesthetic or functional deformities. Proper classification of the wound enables appropriate treatment, and helps predict the postoperative appearance and function. Comprehensive care of trauma patients requires a diverse breadth of skills, beginning with an initial evaluation, followed by resuscitation. Traditionally, facial defects have been managed with closure or grafting, and prosthetic obturators. Sometimes, however, large defects cannot be closed using simple methods. Such cases, which involve exposure of critical structures, bone, joint spaces, and neurovascular structures, requires more complex treatment. We reviewed and classified causes of significant trauma resulting in facial injuries that were reconstructed by microsurgical techniques without simple sutures or coverage with partial flaps. A local flap is a good choice for reconstruction, but large defects are hard to cover with a local flap alone. Early microsurgical reconstruction of a large facial defect is an excellent choice for aesthetic and functional outcomes.

Alar crease as a donor site for the extension limb of modified nasolabial V-Y advancement flap

  • Yooseok Ha;Yunsung Park;Hyunwoo Kyung;Sang-Ha Oh
    • Archives of Craniofacial Surgery
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    • v.24 no.6
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    • pp.260-265
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    • 2023
  • Background: The traditional nasolabial V-Y advancement flap is widely used for midface reconstruction, particularly for the lower third of the nose and upper lip, as its color and texture are similar to these areas. However, it provides insufficient tissue to cover large defects and cannot restore the nasal convexity, nasal ala, and adjacent tissues. The purpose of this study is to investigate the modified nasolabial V-Y advancement flap with extension limbs the along alar crease for the reconstruction of complex midface defects. Methods: A retrospective analysis of 18 patients, who underwent reconstruction with the modified nasolabial V-Y advancement flap, was performed between September 2014 and December 2022. An extension limb was added along the alar crease, adjacent to the defect area, and was hinged down as a transposition flap at the end of the advancement flap. Results: The extension limb along the alar crease successfully covered large and complicated defects, including those of the ala, the alar rim, the alar base, the nostrils, and the upper lip, with minor complications. Conclusion: The alar crease is a good donor site for the reconstruction of large and complex nasal and upper lip defects.