• Korean Journal of Materials Research
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• v.23 no.1
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• pp.72-80
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• 2013

Recently, consumption of magnesium alloys has increased especially in the 3C (computer, communication, camera) and automobile industries. The structural application of magnesium alloys has many advantages due to their low densities, high specific strength, excellent damping and anti-eletromagnetic properties, and easy recycling. However, practical application of these alloys has been limited to narrow uses of mild condition, because they are inferior in corrosion resistance and wear resistance due to their high chemical reactivity and low hardness. Various wet and dry processes are being used or are under development to enhance alloy surface properties. Various conversion coating and anodizing methods have been developed in a view of eco-friendly concept. The conventional technologies, such as diffusion coating, sol-gel coating, hydrothermal treatment, and organic coating, are expected to be newly applicable to magnesium alloys. Surface treatments for metallic luster or coloring are suggested using the control of the micro roughness. This report reviews the recent R&D trends and achievements in surface treatment technologies for magnesium alloys.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.246-250
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• 2000

The oral screen is a functional appliance, suitable for the treatment of developing malocclusion associated with aberrant muscular patterns. The better muscle balance between tongue and the buccinator mechanism can be established, and the reestablishment of normal growth and development can be achieved. The oral screen can be used for the correction of the following conditions : (1) thumbsucking, tongue thrusting and lip biting, (2) mouth breathing, (3) mild distocclusion with premaxillary protrusion, (4) open bites in deciduous and mixed dentition, and (5) incompetent lips. The patient should wear the oral screen every night and also during the day whenever possible. The effects of oral screen can be elevated through lip seal exercise : the lips should be kept in contact all the time to improve the lip seal. In the presented two cases, the patients were considered mouth breathers and to have incompetent lips, and one patient with maxillary incisal protrusion and the other with open bite. They were instructed to wear the oral screen with lip seal exercise. After wearing the appliance for 1 and 2 years respectively, mouth breathing was decreased and lip length and strength were increased, the maxillary incisors were retruded and open bite reduced.

• Journal of the Korea Society of Computer and Information
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• v.27 no.8
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• pp.161-168
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• 2022

In this study, a survey on the wearing satisfaction of commercial men's upper body correction underwear was conducted targeting mildly obese men in their twenties, and it was intended to suggest improvement points for the correction underwear. The product used for the study was Adapt's 95 PROBLEM, and 15 subjects were selected as males in their 20s with a BMI of 25-30 (mild obesity). As a result, men's awareness and interest in corrective underwear were low. In the wearing satisfaction survey, 74% of those who answered negatively that it was uncomfortable to wear and take off. In terms of pressure relief, 60% of those who felt the pressure was strong at the beginning, but as time passed, they got used to it and answered that there was no major inconvenience. However, with regard to digestion after a meal, 40% of the subjects felt that the pressure interfered with digestion. There were many deficiencies in terms of functionality, with more than half of those who responded negatively with regard to stuffiness and heat, and many negative opinions regarding sweat absorption and discharge. In the visual section, positive reaction was shown in chest, side waist and front waist correction, and among them, the front waist had the highest score. In conclusion, it seems that functional parts related to heat and sweat must be improved in consideration of the stuffiness and indigestion brought about by excessive pressure for men's upper body correction underwear.

• Tribology and Lubricants
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• v.27 no.4
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• pp.193-197
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• 2011

Friction behavior of nanoporous anodic aluminum oxide(AAO) film was investigated. A 60 ${\mu}m$ thick AAO film having nanopores of 45 nm diameter with 105 nm interpore-diatance was fabricated by mild anodization process. The AAO film was then saturated with paraffinic oil. Reciprocating ball-on-flat sliding friction tests using 1 mm diameter steel ball as the counterpart were carried out with normal load ranging from 0.1 N to 1 N in an ambient environment. The morphology of worn surfaces were analyzed using scanning electron microscopy. The friction coefficient significantly increased with the increase of load. The boundary lubrication layer of paraffinic oil contributed to the lower friction at relatively low load (0.1 N), but it is less effective at high load (1 N). Plastic deformed layer patches were formed on the worn surface of oil-enriched AAO at relatively low load (0.1 N) without evidence of tribochemical reaction. On the other hand, thick tribolayers were formed on the worn surface of both oil-enriched and as-prepared AAO at relatively high load (1 N) due to tribochemical reaction and material transfer.

• The Journal of Internal Korean Medicine
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• v.10 no.1
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• pp.105-123
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• 1989

Yuk Gi (六氣) in oriental medicine have influence on the body and, the body which adapt itself to the change of Yuk Gi, can maintain the activity of life, so five vital organs of the body have relation to Yuk Gi. The relation between Lung and Jo (燥) is well described from Whang Jae Nai Kyung (黃帝內經), the oldest book in oriental medicine, to the old books of Chung (淸) dynasty and modern documents. By the way, when autumn has come and the environment become dry, clear and mild ability of lung is losed. It's because dryness evil (燥邪) occured the trouble of Lung. The following results were obtained according to these facts which is considreed peviodically and bibliographically. 1. According to flourishing the functional activities of dryness (燥氣), as reducing the functional activities of water (水氣) of upper portion of the body cavity (上焦), Kidny Water (腎水) is not nutrited and Fire-Heat (火熱) is activiting, which is evoking the disease of Lung. 2. In the disease of Lung, there are many diseases because of dryness evil (燥邪), thinking that, which methods of treatment are the principal one of 'Clear up the lung and moisten dryness (淸肺潤煥)'. I found that Lung and Jo (燥) have the relation of intimacy. 3. Creating the vital essence of the kidney (腎水) to the functional activities of the lung (肺氣) is in prosperous condition, the functional activities of fire (火氣) stabilize the function of Lung become normal condition which wear said in the literary.

• Journal of Trauma and Injury
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• v.24 no.2
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• pp.61-67
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• 2011

Purpose: Lawn trimmers are widely used to cut the weeds around graves in South Korea, but they can cause ocular injury. We investigate at the emergency room the incidence and the clinical features of ocular trauma induced by lawn trimmers. Methods:The authors analyzed 106 patients who visited Konyang University Hospital's emergency room from March 1, 2007, to October 31, 2011, because of ocular trauma caused by a lawn trimmer. Patients were sorted into two groups, severe ocular injury and mild ocular injury. Results: Over a 5-year period, 106 patients with ocular trauma caused by a lawn trimmer underwent clinical study. Most of the patient (103 patients) were males, and the average age of the patients was $51.75{\pm}11.66$ years. The incidence of ocular trauma peaked in the sixth decade of life. Most injuries occurred between July and September. Severe ocular injury developed in 46.2% of all patients. As age increased, so did the severity of the ocular injury. The impacting object was a small stone in 43.4% of all patients. Nobody wore protective gear. The most common diagnosis were corneal abrasion, followed by intraocular foreign body, corneal laceration, and sclera laceration. Fifty-four patients were followed up, and thirty-six patients of them had severe injury. The most common complication was a traumatic cataract. Conclusion: Ocular trauma induced by a lawn trimmer is more severe than general ocular trauma. We suggest that everyone using a lawn trimmer should wear protective gear and follow safety guidelines.