• Tribology and Lubricants
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• v.26 no.6
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• pp.336-340
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• 2010

Ultrasound thermography detects defects by radiating 20 ~ 30 kHz ultrasound waves to the samples and capturing the heat generated from the defects with the use of an infrared thermographic camera. This technology is being spotlighted as a next-generation NDE for the automobile and aerospace industries because it can test large areas and can detect defects such as cracks and exfoliations in real time. The heating mechanism of the ultrasound vibration has not been accurately determined, but the thermomechanical coupling effect and the surface or internal friction are estimated to be the main causes. When this heat is captured by an infrared thermographic camera, the defects inside or on the surface of objects can be quickly detected. Although this technology can construct a testing device relatively simply and can detect defects within a short time, there are no reliable data about the factors related to its detection ability. In this study, the ultrasound thermography technique was used to manufacture gasoline and diesel engine piston specimens, and nondestructive reliability tests to verify the applicability and validity of the ultrasound thermography technique.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.7
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• pp.557-561
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• 2001

Chemical mechanical polishing (CMP) process has been widely used to planarize dielectric layers, which can be applied to the integraded circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of in the defect-free inter-level dielectrics (ILD). Especially, defects such as micro-scratch lead to severe circuit failure which affect yield. CMP slurries can contain particles exceeding 1㎛ in size, which could cause micro-scratch on the wafer surface. The large particles in these slurries may be caused by particles agglomeration in slurry supply line. To reduce these defects, slurry filtration method has been recommended in oxide CMP. In this work, we have studied the effects of filtration and the defect trend as a function of polished wafer count using various filters in inter-metal dielectrics(IMD)-CMP process. The filter installation in CMP polisher could reduce defects after IMD-CMP process. As a result of micro-scratch formation, it is shown that slurry filter plays an important role in determining consumable pad lifetime. The filter lifetime is dominated by the defects. We have concluded that slurry filter lifetime is fixed by the degree of generating defects.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.103-110
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• 1997

Since R.Y. Song(1982) has reported anatomic studies about septocutaneous perforator flap, various experiences especially on thigh flaps pedicled on septocutaneous artery were reported. Baek(1983) reported an anatomic study through the cadavers dissections on medial, lateral thigh area and provided the first new cutaneous free flap of thigh for clinical use. Song, et a1.(1984) reported anterolateral thigh free flap, Koshima, et al.(1989) reported pedicle variations and its versatile clinical usages. According to their reports, accessory branches of lateral femoral circumflex artery are placed in comparatively constant location and proved to be the effective pedicle of this flap. The advantages of anterolateral thigh free flap are 1) comparatively thin 2) can obtain sufficiently large flap 3) can contain cutaneous nerve 4) can be easy to approach anatomically because pedicle is located in comparatively constant position 5) minimal donor site morbidity. We report the experience of 10 cases of anterolateral thigh free flap coverage for soft tissue defects: 4 cases of soft tissue defects on foot area, 2 cases of soft tissue defects on hand, 3 cases of partial tongue defects owing to tongue cancer ablation, and 1 case of soft tissue defect on nasal alar.

• Archives of Reconstructive Microsurgery
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• v.23 no.2
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• pp.101-104
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• 2014

Reconstruction of soft tissue defects of the knee has always been a challenging task for plastic surgeons. Various reconstructive choices are available depending on the location, size, and depth of the defect relative to the knee joint. Defects on the knee joint have several characteristic features. The use of a free flap is preferred for reconstructions involving obliteration of large-cavity defects, but recipient pedicle isolation can be difficult because of the extent of the injury zone. Furthermore, the true defect during knee joint flexion is larger than during knee joint extension, and a durable flap is necessary for joint movement. We report for the first time on the use of pedicled perforator flaps for reconstruction of bilateral knee defects in a 76-year-old woman. The operative procedure required skeletonizing the perforators of an antero-lateral thigh flap and antero-medial thigh flap and rotating the flap in the defect. The patient returned to normal daily activity and had a full range of motion two months after the accident. The shorter operating time with decreased donor site morbidity and its durability make this flap a valuable alternative for soft tissue reconstruction of the knee.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.3
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• pp.243-249
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• 1997

The purpose of this study is to describe the clinical availability of a variety of intraoral local flaps in reconstruction of oral soft tissue defects, Forty patients with oral soft tissue defects were treated by tongue, buccinator, palatal, labial, facial artery musculomucosal, buccal fat pad, and masseter muscle crossover flap. Total 43 intraoral flaps were used to reconstruct a variety of intraoral soft tissue defects, such as oronasal fistula, oroantral fistula, traumatic deformities and other. The age of patients ranged from 7 to 72 years, with mean age of 39.6 years. Follow up period ranged from 2 to 66 months, mean follow up period of 21.6 months. There were 9 complications, of which four were partial necrosis, three infections, one total necrosis, and 1 speech problem. Except for total necrosis, most of the recipient sited healed uneventually without severe morbidity. We consider that a variety of intraoral local flaps can be available for reconstruction of small of moderate large intraoral soft tissue defects.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.214-217
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• 2017

The reconstruction of the mandibulofacial defects is a difficult task when there are full-thickness cheek defects involving mandible, inner mucosa and outer skin. There are several reconstructive options for the coverage of large defects, but most of the methods are complicated, and time- and effort-consuming. We hereby present a case of fibula osteocutaneous flap based on a single peroneal artery perforator in the reconstruction of a three-dimensional mandibulofacial defects.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.3
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• pp.209-213
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• 1995

Various cutaneous as well as myocutaneous flaps have been designed for the reconstruction of tissue defects caused by the excision of oral cancer. Among these flaps, cervical island skin flap have been introduced by Farr et al and more have developed by Tashiro et al. This flap has many advantages. The flap minimizes donor size by use of cervical operation wound, flap size available is adequate for most oral defects and the procedure is relatively simple and time saving. However, this flap is not applicable in patients where there are large tissue defects and metastasis is suspected. We used this flap for it's rapid, simple, and effective, primary closure of oral defects after cancer ablation and we have found this flap very useful for the reconstruction of relatively small oral defects.

• Journal of Applied Reliability
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• v.17 no.3
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• pp.224-235
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• 2017

Purpose: Reliability is the most important factor to detect defects as wind turbines are deployed in large blades. The methods of detecting defects are various, such as non-destructive inspection and thermal imaging inspection. We propose the phased array ultrasonic testing method of non-destructive testing. Methods: We propose the active pressure mechanism for wind power blade. The phase array ultrasonic inspection method is used for fault detection inner blade surface. Controlled pressure of mechanism with respect to z-axis is important for guarantee the result of phase array ultrasonic inspection. The model based control and proposed mechanism are utilized for overall system stability and effectiveness of system. Result: The result of proposed pressure mechanism B is more stable than A. Convergence speed is also faster than A. Conclusion: We confirmed the performance of the proposed constant pressure mechanism through experiments. Non-destructive testing was applied to the specimen to confirm the reliability of detecting defects.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.17-17
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• 2000

The issue of reflow profiling continues to be a complex topic. The pains often associated with profiling can be reduced greatly if certain guidelines are followed and if there is a strong understanding of the variables that can be encountered during the reflow process. This paper shall discuss the appropriate guidelines and trouble shooting methods for reflow profiling, and in particular shall focus upon the benefits of implementing the linear ramp-to-spike profile. Delta T(T) is defined as the variation of temperature found on an assembly during the reflow process. Too large of a T can result in soldering defects, so to combat T a Ramp-Soak-Spike(RSS) reflow profile often is utilized. However, when using a newer-style reflow oven, the T often is minimized or eliminated, thus, the soak zone of the reflow profile becomes an unnecessary step. Because of this, the implementation of a linear Ramp-To-Spike(RTS) reflow profile should be considered. Benefits such as reduced energy costs, reduced solder defects, increased efficiency, improved wetting, and a simplification of the reflow profile process may be experienced when using the RTS profile. Included in this paper are the suggested process parameters for setting up the RSS and RTS profiles and the chemical and metallurgical reactions that occur at each set point of these profiles. The paper concludes with a discussion and pictures of several profile-related defects. Each of these defects is described, analyzed, and instructions are given for troublshooting these defects.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.13-18
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• 2010

Purpose: Nasal defect can be caused by excision of tumor, trauma, inflammation from foreign body reaction. Nose is located in the middle of face and protruded, reconstruction should be done in harmony with size, shape, color, and textures. We report various methods of nasal reconstruction using local flaps. Methods: From March 1998 to July 2008, 36 patients were operated to reconstruct the nasal defects. Causes of the nasal defects were tumor (18 cases), trauma (11 cases), inflammation from foreign body reaction (5 cases) and congenital malformation (2 cases). The sites of the defects were ala (22 cases), nasal tip (8 cases) and dorsum (6 cases). The thickness of the defects was skin only (5 cases), dermis and cartilagenous layer (7 cases) and full-thickness (24 cases). According to the sites and thickness of the defects, various local flaps were used. Most of alar defects were covered by nasolabial flaps or bilobed flaps and the majority of dorsal and tip defects were covered by paramedian forehead flaps. Small defects below $0.25 cm^2$ were covered with composite graft or full-thickness skin graft. Results: The follow-up period was 14 months. Partial flap necrosis was observed in a case, and one case of infection was reported, it was improved by wound revision and antibiotics. Nasal reconstruction with various local flaps could provide satisfactory results in terms of color and texture match. Conclusion: The important factors of nasal reconstruction are the shape of reconstructed nose, color, and texture. Nasolabial flap is appropriate method for alar or columellar reconstruction and nasolabial island flap is suitable for tip defect. The defect located lateral wall could be reconstructed with bilobed flap for natural color and texture. Skin graft should be considered when the defect could not afford to be covered by adjacent local flap. And entire nasal defect or large defect could be reconstructed by paramedian forehead flap.