• Journal of Ocean Engineering and Technology
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• v.22 no.2
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• pp.72-77
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• 2008

The application of infrared thermography for detecting defects under the surface of a material was studied. Defects in a specimen were made by back-drilled circular holes. To get alarge temperature difference at the surface, a halogen lamp was used for surface heating. We confirmed that the defect location had a good relationship with the maximum temperature difference. The sizes of the defects could be calculated by means of the FWHM. The value of the FWHM of a temperature difference decreased with time. Therefore in an extremely short time after the heating, the true defect size could be measured.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.11
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• pp.23-29
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• 2010

This paper presents a method for constructing a memory system using defective memory chips comprising faulty storage blocks. The three-dimensional memory system introduced here employs a die-stacked structure of faulty memory chips. Signals lines passing through the through-silicon-vias (TSVs) connect chips in the defect tolerant structure. Defective chips are classified into several groups each group comprising defective chips having faulty blocks at the same location. A defect tolerant memory system is constructed using chips from different groups. Defect-free storage blocks from spare chips replace faulty blocks using additional routing circuitry. The number of spare chips for defect tolerance is $s={\ulcorner}(k{\times}n)/(m-k){\urcorner}$ to make a system defect tolerant for (n+s) chips with k faulty blocks among m independently addressable blocks.

• Archives of Craniofacial Surgery
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• v.20 no.1
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• pp.17-23
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• 2019

Background: The resection of head and neck cancer can result in postoperative defect. Many patients have difficulty swallowing and masticating, and some have difficulty speaking. Various types of flaps are used for palatal reconstruction, but flap selection remains controversial. Therefore, our study will suggest which flap to choose during palatal reconstruction. Methods: Thirteen patients who underwent palatal reconstruction from 30 January, 1989 to 4 October, 2016 at our institution. Size was classified as small when the width was < $4cm^2$, medium when it was $4-6cm^2$, and large when it was ${\geq}6cm^2$. Based on speech evaluation, the subjects were divided into a normal group and an easily understood group. After surgery, we assessed whether flap selection was appropriate through the evaluation of flap success, complications, and speech evaluation. Results: Defect size ranged from $1.5{\times}2.0cm$ to $5.0{\times}6.0cm$. In four cases, the defect was in the anterior third of the palate, in eight cases it was in the middle, and there was one case of whole palatal defect. There were three small defects, two medium-sized defects, and eight large defects. Latissimus dorsi free flaps were used in six of the eight large defects in the study. Conclusion: The key to successful reconstructive surgery is appropriate selection of the flap with reference to the characteristics of the defect. Depending on the size and location of the defect, the profiles of different flaps should be matched with the recipient from the outset.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.101-106
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• 2020

This research is related to a development of the ultrasonic detector for an internal defect detection of various assembly part's welding zone. In this research, measurement S/Ws including system's motion control, S/W ultrasonic transmitter/receiver control, defect judgment standard setting, etc. have been designed for ultrasonic detection, and welding defects sample network, etc. were also designed for comparison between products in good condition and defective products. Through this kind of system, automatic detection function can be performed for the depth and the defect location of the assembly parts welding zone, and the system is able to make a judgment of internal defect detection which is used to be performed by an expert in the past.

• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.56-61
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• 1996

The nasal ala and columella represent a difficult location for reconstruction, especially when defect area is covered with scar. Local flap, such as forehead flap or nasolabial flap, may result in additional facial scarring and bulkiness that require multiple thinning revisions. Recent delineation of vascular territories of the ear has allowed the use of vascularized auricular free flap in the reconstruction of large ala and columella defects. Authors reconstructed two cases of full thickiness defect of the ala and columella with auricular free flap. The pedicle of this flap is the superficial temporal artery and vein. The donor vessels were anastomosed to the facial artery and vein. The results were satisfactory cosmetically and functionally.

• Journal of Korean Neurosurgical Society
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• v.53 no.5
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• pp.300-302
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• 2013

Reports of traumatic leptomeningeal cysts (TLMC) are rare in adults. The standard treatment approach is craniectomy with careful exposure of the intact dural edges, followed by duroplasty. However, occasionally, the location of the TLMC makes achieving watertight duroplasty impossible. Herein, we report the case of a 28-year-old male who presented with a soft growing mass on the vertex of his head 16 months after the head trauma. Upon enhanced CT examination, a bony defect involving both the inner and outer table of the cranium was observed close to the sagittal sinus, and a well-defined cystic mass, 5 cm in diameter, was nested within the defect. The risks associated with extension craniotomy were high because the lesion was located superficial to the sagittal sinus, we opted to use fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) to repair the dural defect. Two months after surgery, the patient remained asymptomatic with a good cosmetic result. In cases like ours, when the defect is near the major sinuses and the risk of rupturing the sinus during watertight dural closure is high, fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) is an effective alternative approach to standard dural suture techniques.

• Korean Journal of Materials Research
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• v.11 no.9
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• pp.781-785
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• 2001

The thermal behavior of Flow Pattern Defect (FPD) and Large Pit (LP) in Czochralski Silicon crystal was investigated by applying high temperature annealing ($\geq$$1100^{\circ}C$) and non-agitated Secco etching. For evaluation of the effect of LP upon device performance/yield, commercial DRAM and ASIC devices were fabricated. The results indicated that high temperature annealing generates LPs whereas it decreases FPD density drastically. However, the origins of FPD and LP seemed to be quite different by not showing any correspondence to their density and the location of LP generation and FPD extinction. By not showing any difference between the performance/yield of devices whose design rule is larger than 0.35 $\mu\textrm{m}$, LP seemed not to have detrimental effects on the performance/yield.

• Korean Journal of Head & Neck Oncology
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• v.38 no.2
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• pp.33-36
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• 2022

Squamous cell carcinoma is the most common cancer occurring in the oral cavity and oncologic wide cancer excision is a major cause of large lip defects. Large lower lip defect reconstruction with good functional and aesthetic results has always presented a challenge for plastic surgeons. There are various lower lip reconstruction methods depending on its size, location, and surgeon's expertise. This is a case of a large defect spanning more than two-thirds of the lower lip after wide excision due to squamous cell carcinoma. The Karapandzic flap was used to reconstruct the defect with a commissuroplasty carried out in a second operation, which yielded a relatively good functional and aesthetic result. No recurrences or metastases were observed within a one year follow-up period.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.3
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• pp.96-102
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• 2005

Acoustic Emission(AE) technique has been applied to not only material characterization evaluation but also on-line monitoring of the structural integrity. The AE source location technique is very important to identify the source, such as crack, leak detection. Since the AE waveforms obtained from sensors are very difficult to distinguish the defect signals, therefore, it is necessary to consider the signal analysis of the transient wave-form. In this study, we have divided the region of interest into a set finite elements, and calculated the arrival time differences between sensors by using the velocities at every degree from 0 to 90. A new technique for the source location of acoustic emission in fiberboard plates has been studied by introducing Wavelet Transform(WT) do-noising technique. WT is a powerful tool for processing transient signals with temporally varying spectra. If the WT de-noising was employed, we could successfully filter out the errors of source location in fiberboard plates by arrival time difference method. The accuracy of source location appeared to be significantly improved.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.11
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• pp.1937-1942
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• 2016

Unlike oil immersed transformers, cast-resin transformers have the solid insulator 'epoxy resin' in sealed structure. Therefore, they reveal a lot of limitations in checking aging conditions and predicting an accident. This study analyzed the characteristics of Cast-resin transformers by the measurement distance and measurement sensitivity with a corona defect sample, using antenna sensor. Therefore, the experiment has proven that the antenna sensor-based measurement method proposed in this study is able to detect the insulation defect location of the cast-resin transformer, unlike conventional measurement methods. It is expected that the result of this study will be used to develop a new type of measuring method in order to measure insulation defects and to use in safety inspection of domestic cast-resin transformers.