• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.96-115
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• 2013

This article describes the concept and the trend of antimicrobial coating agents, which will help to establish the direction of the research and development on antimicrobial coating agent. Antimicrobial agents are compounds that inhibit or kill microorganisms. They are classified into inorganic, metallic, low molecular weight organic, natural organic, and polymeric compounds. Antimicrobial coatings are applied to the surface of daily necessities, medical devices, industrial products, electrical appliances, fabrics, and interior building materials, etc. Conventional antibiotics penetrate microbes without damaging bacterial cell walls, leading to drug resistance which polymeric antimicrobials can prevent by disrupting cell walls. Most polymeric antimicrobials are focused on cationic polymers. Improvement in the selectivity and durability of antimicrobials and reduction of their toxicity will come true by more reasonable design of molecular structures and their combination in coating system.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1962-1963
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• 2002

The hand-piece fiber optics is applied to medical appliances such as glaucoma theraphy to focus semiconductor laser on the affected parts efficiently. In this paper, we evaluate optical properties such as beam power and radius of a hand-piece probe by experiments and we also simulate the hand-piece optics by ray tracing method in order to study major parameters to optimize focalization ability. As results, we show experimental and simulation results of the hand-piece optics and also summarize several requirements that have to be considered in optimizing the hand-piece optics.

• Journal of Magnetics
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• v.22 no.2
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• pp.181-187
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• 2017

Flow of electrically conducting nanofluids is of pivotal importance in countless industrial and medical appliances. Fluctuations in thermophysical properties of such fluids due to variations in temperature have not received due attention in the available literature. Present investigation aims to fill this void by analyzing the flow of copper-water nanofluid with temperature dependent viscosity past a Riga plate. Strong wall suction and viscous dissipation have also been taken into account. Numerical solutions for the resulting nonlinear system have been obtained. Results are presented in the graphical and tabular format in order to facilitate the physical analysis. An estimated expression for skin friction coefficient and Nusselt number are obtained by performing linear regression on numerical data for embedded parameters. Results indicate that the temperature dependent viscosity alters the velocity as well as the temperature of the nanofluid and is of considerable importance in the processes where high accuracy is desired. Addition of copper nanoparticles makes the momentum boundary layer thinner whereas viscosity parameter does not affect the boundary layer thickness. Moreover, the regression expressions indicate that magnitude of rate of change in effective skin friction coefficient and Nusselt number with respect to nanoparticles volume fraction is prominent when compared with the rate of change with variable viscosity parameter and modified Hartmann number.

• Laser Solutions
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• v.11 no.2
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• pp.26-32
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• 2008

Micro lens array (MLA) is widely used in information technology (IT) industry fields, for examples such as a projection display, an optical power regulator, a micro mass spectrometer and for medical appliances. Recently, MLA have been fabricated and developed by using a reflow method, micro etching, electroplating, micromachining and laser local heating. Laser local thermal-expansion (LLTE) technology demonstrates the formation of microdots on the surface of polymer substrate, in this paper. We have also investigated the new direct fabrication method of placing the MLA on the surface of a SU-8 photoresist layer. We have obtained the 3D shape of the micro lens processed by UV laser irradiation and have experimentally verified the optimal process conditions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.717-719
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• 2009

It is addressed that traditional light systems are improper to be applied practically in the energy efficiency point of view. To overcome such drawback, advanced investigations are recently conducted for realizing remote control of several related equipments such as lights, heats, home appliances, etc. This paper proposes a novel power line communication system to effectively manage lights in which the conventional method is used without any modification. We timely control lights to reduce energy cost based on given time period.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.613-618
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• 2019

EMF (Electromagnetic Field) is a valuable resource for living in a knowledge-based information society. The EMF is used in home appliances that make our lives easy and convenient, and in telecommunication devices such as mobile phones, personal computers, medical devices and broadcasting towers. However, the biological hazards associated with EMF exposure are also increasing in signal from telecommunication devices. Studies of the effects of EMF exposure on humans have been conducted for a long time, but it has not yet been demonstrated whether the EMF effect is harmful. In this paper, we examine the electromagnetic field emitted from various electronic devices around living and its effect.

• Journal of Korean Dental Science
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• v.16 no.2
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• pp.204-210
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• 2023

Lesch-Nyhan syndrome is a rare X-linked recessive disorder characterized by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyl transferase, which is important in the metabolism of purines. Prevalence of Lesch-Nyhan syndrome is 1:100,000 to 1:380,000 live births, and Lesch-Nyhan syndrome mainly affects males. It is characterized by neurologic dysfunction, uric acid overproduction, and cognitive and behavioral disturbances. The self-mutilation is the most distinctive symptom in Lesch-Nyhan syndrome, appearing about 1 year of age. It is expressed as persistent bites in the oral mucosa, tongue, lips, and fingers, which leads to the total or partial destruction of the affected tissues. Several medical and dental management methods might be performed in Lesch-Nyhan syndrome patients. Dental approaches to prevent injuries caused by self-mutilation include treatments with oral appliances such as mouth guards or lip bumpers, extraction, and orthognathic surgery. This report described two brothers with Lesch-Nyhan syndrome, who injured themselves on oral tissues. The methods of tooth reduction and extraction were performed to prevent injuries caused by self-mutilation.

• The Journal of Korean Medicine
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• v.35 no.2
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• pp.12-18
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• 2014

Objectives: This was a retrospective case series about the clinical effect of integrated approach with behavior therapy for obstructive sleep apnea (OSA). Methods: Medical records of twelve patients with OSA who were treated with behavior modification including nasal breathing with oral appliances and sleep in lateral position, oral administration of herbal medicines and acupuncture treatment between January and September of 2013 were reviewed. Apnea-hypopnea index (AHI), day time sleepiness, apneas and hypopneas counts during sleep, risk indicator (RI), oxygen desaturation index, average saturation during sleep, lowest desaturation, lowest saturation, snoring events ratio and number of desaturations (%) were assessed before and after treatments with the ApneaLink device, which is a portable diagnostic apparatus for monitoring airflows of the patient's breath at home. Results: After an average 62.67 (SD 37.16) days of treatment, AHI (from 17.67, 12.79 to 8.75, 8.25, p=0.007), RI (from 22.00, 13.26 to 12.09, 8.03, p=0.004), oxygen desaturation index (from 17.33, 12.17 to 8.17, 7.86, p=0.005), and number of desaturations (from 7.00 times, 9.79 to 0.92 times, 1.39, p=0.044) showed significant improvement. Daytime sleepiness improved from 6.5 (3.2) to 3.8 (1.8) but there was no significant difference after treatment (p=0.17). No adverse events related to treatment were observed during participation in the treatment. Conclusion: From this case series, we found that behavior modification with herbal medication and acupuncture may be effective for improving sleep apnea without serious adverse events. Future randomized controlled trials with larger sample size will be necessary for concrete evidence on the benefit of this integrated treatment for OSA.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.123-130
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• 2008

Purpose: To provide practical education, most universities should be equipped with medical appliances in need. As compensatory measures, Gimcheon College has produced in-house dummy linac and dummy accessories, we are going to report efficiency and its usage. Materials and Methods: Dummy linear accelerator (DLINAC-001) has the same mechanical functions as rotation of gantry and collimation in linear accelerator. In addition, to maximize practical education, we have produced and utilized in-house custom blocks, wedge filters, electron cones and head rests. Results: The in-house produced linear accelerator with the same mechanical functions as the linear accelerator, DLINAC-001 can be effectively used in practicing diverse medical instruments. Conclusion: We have produced dummy linear accelerators and dummy accessories and utilized them in practice classes, which can provide the students with clinical training in diverse fields. Consequently, the students exposed to the maximized educational effectiveness can be easily equipped with the practical competence required in real clinical fields.

• Journal of the Korean Burn Society
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• v.16 no.2
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• pp.99-103
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• 2013

Purpose: The biggest problem of wound healing is a possible occurrence of lesion. Especially, in the case of patients who have a skin injury around exposed body parts, if their treatment period drag on for long time, they can suffer from aftereffects and the costs can be passed on to a society. Therefore, in this research, we investigated the need to develop the effective medicine and appliances for the patients by examining which therapy methods are being applying to the skin damage and what is the advantage and limit by evaluating the patient's satisfaction level. Methods: We carried out an online and offline survey targeting medical teams in order to analyze device for wound care. A total of 125 medical teams applied to the research, and investigate the level of customer satisfaction. Results: The moist dressings are the most used method for wound healing. When it comes to the level of customer satisfaction, biological dressing product also has a high satisfaction level. However its high cost tends to limit the use. Conclusion: This research reached a conclusion that it is need to develop a low cost and high efficiency wound care product considering the fact that its high cost and low efficiency induced economic problems. Generally, it is needed to develop a product for skin regeneration based on biological technologies, not a product just for damage cure.