• Journal of the Korean Arthroscopy Society
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• v.12 no.1
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• pp.66-68
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• 2008

Recently, devices using radiofrequency energy have been developed for arthroscopic soft tissue ablation, cauterization and shrinkage. After ACL reconstruction operation, articular metallic foreign body was found in the post-operative radiographs. It was proven to be the tip of bipolar radiofrequency system after foreign body removal. After that we experienced 2 more cases during the acromioplasty procedure. We requires attention to prevent the separation of the tip from the body in the arthroscopic surgery using bipolar radiofrequency system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.2
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• pp.79-82
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• 2003

GaN nanoparticles were synthesized by the pulsed laser deposition (PLD) process on $SiO_2$substrate after irradiating the surface of the GaN sintered pellet by the ArF (193 nm) excimer laser. At this moment Ar gas pressure of 100 Pa, 50 Pa, 10 Pa and 1 Pa were applied during the ablation process and laser power of 100 mJ and 200 mJ were also applied. The synthesized fan nanoparticles were characterized by XRD, SEM, TEM, XPS and optical absorption spectra. The synthesized GaN nanoparticles had the crystallite sizes of 20~30 nm, and besides, GaN nanoparticles synthesized under low Ar gas pressure compared to the others corresponded with stoichiometry, and the optical band edge of the GaN nanoparticles was blueshifted.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.1
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• pp.68-75
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• 2015

In this paper, unsteady characteristics of pressure in solid rocket motor were analyzed by using response of pintle actuation, pressure and thrust data from ground test. Pressure and thrust in solid rocket motor can be controlled in real time by varying nozzle throat area with pintle, installed in the valve. Unsteady characteristics of pressure can be observed in this system occurred by various reasons. Two critical reasons, error of pintle actuation and ablation of center tube, are found and effects of each reason can be analyzed individually by re-prediction of pressure with response of pintle actuation and analyzing thrust to pressure ratio.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.3
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• pp.73-76
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• 2020

Silver nanowires (AgNWs) intrinsically possess high conductivity, ductility, and network structure percolated in a low density, which have led to many advanced applications of transparent and flexible electronics. Most of these applications require patterning of AgNWs, for which photolithographic and printing-based techniques have been widely used. However, several drawbacks such as high cost and complexity of the process disturb its practical application with patterning AgNWs. Herein, we propose a novel method for the patterning of AgNWs by employing UV-curable adhesive tape with a structure of liner/adhesive layer/polyolefin (PO) film and UV irradiation to simplify the process. First, the UV-curable adhesive tape was attached to AgNWs/polyurethane (PU), and then selectively exposed to UV irradiation by using a photomask. Subsequently, the UV-curable adhesive tape was peeled off and consequently AgNWs were patterned on PU substrate. This facile method is expected to be applicable to the fabrication of a variety of low-cost, shape-deformable transparent and wearable devices.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.6
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• pp.21-27
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• 2019

Cellulose-based carbon fabrics are used in aerospace nozzles have low thermal conductivity and high ablation resistance. However, there is a disadvantage in that the weight is reduced by 70~90% in the pyrolysis process and graphitization process and the residual rate is low when the final carbon fabric is produced. In this study, phosphoric acid as a phosphorus flame retardant and Citric acid as a cross-linking agent were treated on the lyocell fabrics. After that the functional groups were identified and thermal properties were confirmed by FT-IR, XRD and TGA. The yields of the final carbon fabrics were also compared through the pyrolysis and graphitization process. The graphitized yield increased to 8.1% with increasing citric acid to 16 wt% added.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.367-375
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• 2012

Midfacial reconstruction following resection of extensive malignant oral cavity tumors constitutes a challenging problems for reconstructive surgeons. Rectus abdominis muscle free flap (RAMFF) can be considered as the optimal reconstructive option in this case, because this flap has some advantages including consistent deep inferior epigastric artery anatomy, easy to dissect with well defined skin boundaries, acceptable donor site morbidity and the ability to perform simultaneous flap harvest with oral cancer ablation surgery. The rectus abdominis muscle forms an important part of the anterior abdominal wall and flexes the vertebral column, which is a long strap-like muscle divided transversely by three tendinous intersections, fibrous bands which are adherent to the anterior rectus sheath, which is thickly enclosed by the rectus sheath, except for the posterior part below the arcuate line that is usually located midway between the umbilicus and symphysis pubis. Below the arcuate line, this muscle lies in direct contact with the transversalis fascia and parietal peritoneum. For the better understanding of RAMFF as a routine reconstructive procedure in oral and maxillofacial surgery, the constant anatomical findings muse be learned and memorized by the young doctors in the course of the special curriculum periods for the Korean national board of oral and maxillofacial surgery. This review article will discuss the anatomical basis of RAMFF with Korean language.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.2
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• pp.197-204
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• 2012

We explore the evolution of metal plasma generated by high laser irradiances and its effect on the surrounding air by using shadowgraph images after laser pulse termination and X-ray diffraction (XRD) of aluminum plasma ablated by a high-power laser pulse (>1000 mJ/pulse) and oxygen from air. Hence, the formation of laser-supported detonation and combustion processes has been investigated. The essence of this paper is in observing the initiation of chemical reaction between the ablated aluminum plasma and oxygen from air by the high-power laser pulse (>1000 mJ/pulse) and in conducting a quantitative comparison of the chemically reactive laser-initiated waves with the classical detonation of an exploding aluminum (dust) cloud in air. The findings in this work may lead to a new method of initiating detonation from a metal sample in its bulk form without any need to mix nanoparticles with oxygen for initiation.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.353-358
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• 2013

Background Robots have allowed head and neck surgeons to extirpate oropharyngeal tumors safely without the need for lip-split incision or mandibulotomy. Using robots in oropharyngeal reconstruction is new but essential for oropharyngeal defects that result from robotic tumor excision. We report our experience with robotic free-flap reconstruction of head and neck defects to exemplify the necessity for robotic reconstruction. Methods We investigated head and neck cancer patients who underwent ablation surgery and free-flap reconstruction by robot. Between July 1, 2011 and March 31, 2012, 5 cases were performed and patient demographics, location of tumor, pathologic stage, reconstruction methods, flap size, recipient vessel, necessary pedicle length, and operation time were investigated. Results Among five free-flap reconstructions, four were radial forearm free flaps and one was an anterolateral thigh free-flap. Four flaps used the superior thyroid artery and one flap used a facial artery as the recipient vessel. The average pedicle length was 8.8 cm. Flap insetting and microanastomosis were achieved using a specially manufactured robotic instrument. The total operation time was 1,041.0 minutes (range, 814 to 1,132 minutes), and complications including flap necrosis, hematoma, and wound dehiscence did not occur. Conclusions This study demonstrates the clinically applicable use of robots in oropharyngeal reconstruction, especially using a free flap. A robot can assist the operator in insetting the flap at a deep portion of the oropharynx without the need to perform a traditional mandibulotomy. Robot-assisted reconstruction may substitute for existing surgical methods and is accepted as the most up-to-date method.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.440-444
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• 2013

Background Axillary osmidrosis is characterized by unpleasant odors originating from the axillary apocrine glands, resulting in psychosocial stress. The main treatment modality is apocrine gland removal. Until now, of the various surgical techniques have sometimes caused serious complications. We describe herein the favorable outcomes of a new method for ablating apocrine glands by minimal subdermal shaving using sclerotherapy with absolute ethanol. Methods A total of 12 patients underwent the procedure. The severity of osmidrosis was evaluated before surgery. Conventional subdermal shaving was performed on one side (control group) and ablation by means of minimal subdermal shaving and absolute ethanol on the other side (study group). Postoperative outcomes were compared between the study and control groups. Results The length of time to removal of the drain was 1 day shorter in the study group than in the control group. There were no serious complications, such as hematoma or seroma, in either group, but flap margin necrosis and flap desquamation occurred in the control group, and were successfully managed with conservative treatment. Six months after surgery, we and our patients were satisfied with the outcomes. Conclusions Sclerotherapy using absolute ethanol combined with minimal subdermal shaving may be useful for the treatment of axillary osmidrosis. It can reduce the incidence of seroma and hematoma and allow the skin flap to adhere to its recipient site. It can degrade and ablate the remaining apocrine glands and eliminate causative organisms. Furthermore, since this technique is relatively simple, it takes less time than the conventional method.

• Journal of Yeungnam Medical Science
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• v.29 no.2
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• pp.136-140
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• 2012

A 61-year-old male who complained of right upper quadrant pain was referred to the authors for evaluation after his computed tomography suggested biliary adenocarcinoma. The lesion consisted of multiple cysts with papillary mass and peri-ampullay mass. The patient underwent an operation due to a clinical suspicion of biliary cystadenocarcinoma, but the pathology confirmed biliary papillomatosis (BP) after diagnosing intrahepatic papillary neoplasm with high-grade dysplasia and invasive adenocarcinoma with papillary neoplasm from the distal common bile duct to the duodenum. BP is a disease characterized by multiple papillary masses. Its cause has yet to be discovered. It commonly manifests as bile duct dilation but rarely as a ductal cystic change. Under computed tomography or magnetic resonance imaging, both the BP and the cystic neoplasm can show bile duct dilation and a papillary mass, which makes their differential diagnosis difficult. A confirmative diagnosis can be made through a pathologic examination. BP is classified as a benign disease that can become malignant and may recur, though rarely. Its treatment of choice is surgical resection. Laser ablation or photodynamic therapy can be used for unresectable lesions. In the case featured in this paper, biliary papillomatosis was difficult to differentiate from cystic adenocarcinoma due to diffusely scattered multiple large cystic lesions in the liver, and it was histologically confirmed to have become malignant with cystic duct dilation after the operation. This case is reported herein with a literature review.