• Transactions of the Korean Society of Mechanical Engineers
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• v.3 no.2
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• pp.60-67
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• 1979

Aerodynamic forces acting on a curved blade are computed theoretically taking into account the variation of wind speed over the blade to investigate the performance of a vertical axis wind rotor. It is shown that the rotor does not self start at the rated wind speed without a supplementary starting device and that most of the power output is contributed by the central portion of the rotor, and the use of spoilers for limiting the maximum rotational speed is needed for safety. It is also shown that provision of skew angle to the blade does not improve the starting characterstics and only reduces the maximum power output. The effects of geometric variables such as skew angle, blade solidity and ratio of the rotor height to diameter are also discussed.

• Childhood Kidney Diseases
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• v.22 no.1
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• pp.32-35
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• 2018

Acute idiopathic scrotal edema (AISE) is a self-limiting condition that is characterized by acute scrotal swelling and erythema. AISE is a very rare cause of acute scrotum, especially in neonates. We report a case of AISE in a 26-day-old infant who was admitted to the outpatient clinic with swelling and erythema of the penis and scrotum for a week. His vital signs were stable, and laboratory findings were non-specific. A diagnosis of AISE was made using scrotal ultrasonography with color Doppler. His symptoms resolved within four days after the onset of supportive treatment, and he was discharged from the hospital. In neonates with an acute scrotum, AISE should be considered to prevent unnecessary surgical exploration.

• Journal of Trauma and Injury
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• v.28 no.3
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• pp.206-210
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• 2015

Cervicofacial subcutaneous emphysema is a rare complication mainly resulting from dental procedures. The majority of cases are self-limiting and benign in clinical nature. However, although entry sites may be quite small and superficial, it can result in potential respiratory difficulties, such as pneumothorax and pneumomediastinum. We present the first case in which facial subcutaneous emphysema developed in a 6-year-old boy following use of a fish cake skewer while eating.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.279-282
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• 1985

Occipital alopecia after Open Heart Surgery under the Cardiopulmonary bypass is an uncommon minor complication. We had experienced Occipital alopecia in 6 cases after Open Heart Surgery. The cause of the alopecia was transient circulatory disturbance due to pressure effect of the patient`s head and intraoperative hypotension. The prodromal symptoms of the alopecia were erythema, itching, and watery discharge, but some patients showed non-specific symptoms. The common site of the alopecia was right occipital region and the size was 2-4 cm in diameter. The regrowth of the hair was completed at postoperative 3 to 5 months without specific treatment except conservative treatment. Fortunately the postoperative alopecia is a self-limiting condition, and spontaneous regrowth of hair is the rule without other complications.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.169-169
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• 2003

실리콘 절연막은 반도체 및 디스플레이 소자의 gate 절연막과 보호막으로, 그리고 배선공정에서는 층간절연막(ILD, Inter Layer Dielectric)으로 사용하는데, 주로 IPCVD, PECVD, APCVD법에 의하여 증착되고 있다. 그러나 이러한 방법들은 반도체 소자의 고집적화가 진행됨에 따라 증착온도와 step coverage 및 물성 이 문제점으로 대두되고 있다. 이러한 문제점들을 해결할 수 있는 원자층 증착(ALD, Atomic Layer Deposition)기술은 기판 표면에서의 self-limiting reaction을 통해 매우 얇은 박막을 형성할 수 있고, 두께 및 조성 제어를 정확히 할 수 있으며, 복잡한 형상의 기판에서도 우수한 step coverage를 얻을 수 있어 초미세패턴의 형성과 매우 얇은 두께에서 균일한 물리적, 전기적 특성이 요구되는 초미세 반도체 공정에 적합하다. 또 저온에서 증착이 가능해 유리를 기판으로 사용하는 TFT-LCD소자의 gate 절연막에 적용이 가능하다.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.382-391
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• 2020

Facial palsy has a broad clinical presentation and the effects on psychosocial interaction and facial functions can be devastating. Pediatric facial palsy, in particular, introduces unique familial and technical considerations as anatomy, future growth potential, and patient participation influence treatment planning. Though some etiologies of pediatric facial palsy are self-limiting, congenital and long-standing facial palsies pose difficult challenges that require a combination of surgical, adjunctive, and rehabilitative techniques to achieve facial reanimation. Given the spectrum of ages and symptom severity, as well as the various surgical options available for facial palsy, a tailored approach needs to be developed for each child to restore facial balance and function. Here, we review the etiologies, workup, and treatment of pediatric facial palsy and present our novel algorithmic approach to treatment.

• Journal of Energy Engineering
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• v.2 no.3
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• pp.285-292
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• 1993

A cylindrical-shape, horizontal furnace was used to investigate the effect of particle size on the pulverized coal combustion behavior. Three differently-sized fractions (5, 30, and 44 microns in average diameter) of high-volatile bituminous coal, were burned in the test furnace. Ignition characteristics of pulverized coal flame were determined through the amount of methane in the carrier gas for the self-sustaining flame. Easiest ignition occurred with the immediately-sized coal particles. Ignition of coal jet flame appeared to occur through a gas-phase homogeneous process for particles larger than 30 microns. Below this limiting size, heterogeneous process probably dominated ignition of coal flame. Oxygen concentration of combustion air was varied up to 50%, to determine the oxygen-enrichment effect on the coal ignition behavior. Oxygen enrichment of primary air assisted ignition behavior of pulverized coal flame. However, enrichment of secondary air didn't produce any effect on the ignition behavior.

• Clinical and Experimental Pediatrics
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• v.55 no.11
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• pp.445-448
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• 2012

Kikuchi-Fujimoto disease (KFD) is a benign self-limiting disease characterized by fever and lymphadenitis. The etiology and pathogenesis of KFD is unclear. However, two hypotheses have been suggested: a viral infection hypothesis and an autoimmune hypothesis. Several KFD patients with various types of autoimmune diseases have been reported, and these reports support the hypothesis for autoimmune pathogenesis of KFD. Here, we report the case of a 17-year-old female patient diagnosed with KFD and autoimmune thyroiditis. This case serves as additional evidence that the etiology of KFD is autoimmune origin.

• Journal of Korean Neurosurgical Society
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• v.44 no.6
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• pp.392-395
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• 2008

Lateral femoral cutaneous neuropathy occurring during spinal surgery is frequently related to iliac bone graft harvesting, but meralgia paresthetica (MP) can result from the patient being in the prone position. Prone position-related MP is not an uncommon complication after posterior spine surgery but there are only few reports in the literature on this subject. It is usually overlooked because of its mild symptoms and self-limiting course, or patients and physicians may misunderstand the persistence of lower extremity symptoms in the early postoperative period to be a reflection of poor surgical outcome. The authors report a case of prone position-related MP after posterior lumbar interbody fusion at the L3-4 and reviewed the literature with discussion on the incidence, pathogenesis, and possible risk factors related to this entity.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.222-230
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• 1991

Pyogenic orofacial infections are most commonly odontogenic in origin. Although such infections are usually self-limiting and spatially confined, purulent material may occasionally borrow deeply into contiguous fascial space or planes far from the initial site of involvement. The incidence of orofacial infection remains low in this modern era of preventive dental care and antibiotic therapy, but severe orofacial infections are most frequently observed in the medically compromised patients. We experienced 5 cases of severe orofacial odontogenic infection associated with medical diseases, and then concluded as follows : 1. The average hospitalized period was about 5 weeks, and the signs that indicated that the infections were controlled usually appeared in third week after incision and drainage. 2. The involved medical diseases were diabetes mellitus iatrogenic Cushing's syndrome, rheumatoid arthritis, malnutrition, etc. 3. The medical diseases should be treated coincidently with control of infection.