• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.11
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• pp.48-57
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• 1993

The ANSI recently adopted normalized site attenuation(NSA) as a validation procedure of open area test sites. In this paper, the theoretical NSA values specified in the truth vlues of NSA were calculated for an ideal test site when tuned dipoles are used. A method of moments technique is employed to evaluate these NSA values. The calculated NSA values are more accurate than that of the ANSI.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.577-583
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• 1990

Subglottic stenosis is a disorder characterized by narrowing of the airway below the glottis. In children, the stenosis is usually due to scar formation secondary to prolonged airway intubation, rather than to external trauma. The location and extent of the stenosis are highly variable, consequently, corrective measures need to be selected to suit the individual problem. Conservative treatment is adequate for lesser degrees of stenosis but those with more severe scarring require external laryngeal surgery. We managed 2 children with subglottic stenosis due to prolonged intubation after open heart surgery who needed a resectional surgery of the stenotic upper airway. The preoperative evaluation and surgical technique for subglottic stenosis were reviewed.

• Journal of Chest Surgery
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• v.48 no.1
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• pp.1-6
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• 2015

Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair.

• Journal of the Korean institute of surface engineering
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• v.33 no.4
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• pp.261-265
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• 2000

Geometrically and chemically well defined Pt/alumina model catalysts have been prepared. To this end, we fabricated electrochemically alumina supports in which pores of constant size, length and shape were regularly distributed over a wide area of the surface. Platinum particles were dispersed on the pore surfaces via organometallic chemical vapor deposition technique using (trimethyl) methylcyclopentadienylplatinum (IV) as a precursor. The chemical composition of the alumina plane surfaces was examined by Auger electron spectroscopy and the adsorption characteristics of the platinum particles were studied by thermal desorption spectroscopy. A variety of industrial catalytic problems are now open for further investigation utilizing the Pt/alumina model catalysts.

• Journal of Advanced Information Technology and Convergence
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• v.8 no.2
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• pp.1-11
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• 2018

Multimedia contents have been increasingly available over the Internet as wireless networks systems are continuously growing popular. Unlimited access from various users has led to unauthorized access of third parties or adversaries. This paper deals with the implementation of elliptic curve cryptography (ECC) based user authentication for securing multimedia contents over the Internet. The ECC technique has been incorporated with the advanced encryption standard (AES) algorithm to ensure the complexity of the proposed authentication scheme and to guarantee authenticity of multimedia services.

• Journal of Chest Surgery
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• v.54 no.1
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• pp.65-67
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• 2021

A fistula between the right pulmonary artery and the left atrium is a very rare congenital anomaly, for which there is no definitive embryogenetic explanation. Patients present with cyanosis or clubbing, and the treatment strategy is to close the fistula, which can be done by an open surgical technique or by percutaneous intervention. Although rare, this condition should be considered in the differential diagnosis when evaluating a patient with central cyanosis.

• Nonlinear Functional Analysis and Applications
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• v.28 no.1
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• pp.237-249
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• 2023

In this paper, by means of the Schauder fixed point theorem and Arzela-Ascoli theorem, the existence and uniqueness of solutions for a class of not instantaneous impulsive problems of nonlinear fractional functional Volterra-Fredholm integro-differential equations are investigated. An example is given to illustrate the main results.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.55 no.9
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• pp.546-551
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• 2012

The endonasal approach for rhinoplasty is an important surgical technique to manage the majority of the nasal problem that present to the nasal plastic surgeons. Open rhinoplasty offers an excellent visualization and therefore facility of precise correction, but causes a larger area of wound and scarring. This review was designed to describe the versatility of endonasal techniques for rhinoplasty.

• Nonlinear Functional Analysis and Applications
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• v.29 no.1
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• pp.165-177
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• 2024

In this paper, we investigate the suitable conditions for the existence results for a class of 𝔍-Hilfer fractional nonlinear Fredholm-Volterra models with new conditions. The findings are based on Banach contraction principle and Schauder's fixed point theorem. Also, the generalized Hyers-Ulam stability and generalized Hyers-Ulam-Rassias stability for solutions of the given problem are provided.

• Journal of Korean Dental Science
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• v.6 no.1
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• pp.4-12
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• 2013

Purpose: This study sought to verify the usefulness of mini-implant and surgical steel wire in the treatment of mandibular fracture through the objective identifi cation of the change of bone structure and bone density before and after reduction by evaluating radiological change through fractal analysis when mandibular fracture is treated using mini-implant and surgical wire. Materials and Methods: This study looked at 45 patients (males: 38, female: 7) diagnosed with mandibular fracture in the oral and maxillofacial surgery division of Chung-Ang University Dental Hospital and who received open reduction and intra-osseous fi xation. Result: The average fracture dimension values were higher for the group of the patients who had mini-implants and surgical wire treatment. Conclusion: Based on the results of the study on the usefulness of the reduction technique using mini-implant and surgical steel wire in the treatment of mandibular fracture through the fractal analysis method, the reduction technique using mini-implant and surgical steel wire is regarded as an effective method of minimizing the gap between mandibular fracture fragments.