• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.723-725
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• 1998

STI CMP process are substituting gradually for LOCOS(Local Oxidation of Silicon) process to be available below sub-0.5um technology and to get planarized. The other hand, STI CMP process(especially STI CMP with RIE etch back process) has some kinds of defect like Nitride residue, Torn Oxide defect, etc. In this paper, we studied how to reduce Torn Oxide defects after STI CMP with RIE etch back process. Although Torn Oxide defects which occur on Oxide on Trench area is not deep and not sever, Torn oxide defects on Moat area is sometimes very deep and makes the yield loss. We did test on pattern wafers witch go through Trench process, APCVD process, and RIE etch back process by using an REC 472 polisher, IC1000/SUV A4 PAD and KOH base slurry to reduce the number of torn defects and to study what is the root causes of torn oxide defects.

• 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 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.

• 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 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.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.1
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• pp.94-101
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• 2009

Complex Products may present more than one type of defects and these defects are not always of equal severity. These defects are classified according to their seriousness and effect on product quality and performance. Demerit systems are very effective systems to monitoring the different types of defects. So, classical demerit control chart used to monitor counts of several different types of defects simultaneously in complex products. S.M. Na et al.(2003) proposed the Demerit-CUSUM for the improvement of the demerit control chart performance and Nembhard, D. A. et al.(2001) and G.Y Cho et al.(2004) developed a Demerit control chart using the EWMA technique and evaluated the performance of the control chart. In this paper, we present an effective method for process control using the Demerit-CUSUM with fast initial response. Moreover, we evaluate exact performance of the Demerit-CUSUM control chart with fast initial response, Demerit-CUSUM and Demerit-EWMA according to changing sample size or parameters.

• 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.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.3
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• pp.299-306
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• 2001

In this paper, artificial and real defects(delamination and debond) in composite structures were detected by using ESPI system. Three types of specimens, that is, composite laminates, honeycomb structures, and adhesive joints, were used to study the applicability of ESPI to composite structures. To detect defects in specimens, we selected thermal loading method that can easily induce the surface deformation of specimen. Experimental results show that defects in composite structures could be easily detected by ESPI. Moreover, it shows that ESPI could be usefully applied to the detection of defects in various composite structures.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.412-422
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• 1999

Scale defects generated on the strip surface in a tandem finishing mill line are collected from the strip trapped among the production mills by freezing the growing scale on the strip by the melt glass coating and shutting down the line simultaneously. The samples observed of its cross sectional figure showed the process of scale defect formation where the defects are formed at the base metal surface by thicker oxidized scale during each rolling passes. The properties of the oxidized layer growth both at rolling and inter-rolling are detected down sized rolling test simulating carefully the rolling condition of the production line. The thickness of the oxidized layer at each rolling pass are simulated numerically. The critical scale thickness to avoid the defect formation is determined through the expression of mutual relation between oxidized layer thickness and the lanks of the strip called quality for the scale defects. The scale growth of scale less than the critical thickness and also to keep the bulk temperature tuning the water flow rate and cooling time appropriately. Two units of Inerstand Cooler are designed and settled among the first three stands in the production line. Two units of scale defect is counted from the recoiled strip and the results showed distinct decrease of the defects comparing to the conventionaly rolled products.