• Title/Summary/Keyword: 손상원인

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Orthodontic Treatment of an Impacted Immature Tooth Using C-tube as a Skeletal Anchorage : Case Reports (C-tube를 골격성 고정원으로 이용한 매복된 미성숙 영구치의 교정적 치료 : 증례 보고)

  • Choi, Sooyeon;Kong, Eunkyung;Chung, Kyurhim;Baek, Kwangwoo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.41 no.2
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    • pp.157-165
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    • 2014
  • Skeletal anchorage is recommended as an orthodontic treatment for an impacted immature permanent tooth. Among these methods, C-tube is relatively safe because it is fixed to the cortical bone of interdental and the lower part of the root with several short miniscrews, which causes less damage to the root in patients of early permanent dentition. As it can be easily bent, the traction direction can be adjusted to favorable bone density sites. However, patient cooperation is important and traction based on physiological force in order to gain root and dentoalveolar tissue development in immature permanent teeth is required. Periodic follow-ups should be mandatory.

Development of HIL simulator for performance validation of stack inlet gases temperature controller of marine solid oxide fuel cell system (선박용 고체산화물형 연료전지 시스템의 스택 공급 가스 온도 제어기 성능 검증을 위한 HIL 시뮬레이터 개발)

  • Ahn, Jong-Woo;Park, Sang-Kyun
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.6
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    • pp.582-588
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    • 2013
  • Solid Oxide Fuel Cell (SOFC) has been focused as a promising power source, which can replace a diesel engine regarding as major source of air pollution by the ship, due to high efficiency and eco-friendly. High operating temperature of SOFC is enable to secure of high efficiency, use various fuels and no need of high priced catalyst, but it may damage to components of SOFC. Therefore temperature control system has to be designed and validated before employing the fuel cell system for securing high efficiency and reliability. In this paper, instead of using typical method to validate performance of the controller, which consumes high cost and time, performance validation system using Hardware-in-the-loop simulation was developed and validated performence of the designed temperature controller for SOFC system.

Assessment of the Anchor Head System Embedded in the Ground Surface (지표면에 근입한 앵커두부처리 시스템의 적용성 평가)

  • Min, Kyoung-Nam;Bae, Woo-Seok;Ahn, Kwang-Kuk;Jeong, Ku-Sic
    • The Journal of Engineering Geology
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    • v.22 no.1
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    • pp.49-58
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    • 2012
  • Anchor heads a recommonly exposed to surface weathering processes that cause physical damage by vibration and external forces. This study presents a new method of anchor-head installation that uses near-surface embedding based on analyses of concrete block failure. ABAQUS 3D numerical modeling performed to compare this method with the standard technique and to analyze the distribution of displacement and the stress pattern. In addition, application of the method to a real-world case was tested by in-situ measurements. The results show a maximum vertical stress of 9.73 MPa and vertical displacement of 1.34 mm. Field tests indicated that displacement of a concrete block was 3 to 4 times greater than that of an embedded bearing plate.

Suggestions for the Effective Intraoperative Neurophysiological Monitoring in Microvascular Decompression Surgery of Hemifacial Spasm (편측성 안면경련 환자의 미세혈관 감압수술에서 효과적인 수술 중 신경계 감시검사를 위한 제안)

  • Lim, Sung-Hyuk
    • Korean Journal of Clinical Laboratory Science
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    • v.48 no.3
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    • pp.262-268
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    • 2016
  • Hemifacial spasm is a disease caused by involuntary facial muscles with repeated unilateral convulsive spasms. It involves contraction of multiple muscles at the same time (synkinesia). The pathogenesis appears to be the pressure on the vessel by the facial nerve. This study included hemifacial spasm patients, who received microvascular decompression surgery. Brainstem auditory evoked potential and the examination time were carefully noted when using brain surgical retractor. The facial nerve electromyography tests for the identification of artifacts and EMG waveform when the facial nerve damage, about the importance of the maintenance of anesthesia in the lateral spread response and in a somatosensory evoked potential propose a new method. Based on the above test, it will be more effective.

Identification of Failure Cause for 300MW LP turbine Blade through Vibration Analysis (진동 해석을 통한 300MW급 저압터빈 블레이드의 손상 원인 규명)

  • Kim, Hee-Soo;Bae, Yong-Chae;Lee, Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.794-799
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    • 2005
  • The failure of blades frequently happened in the 300MW LP turbine until now and they are maintaining the blades periodically during outage. So the blade-disk system is analysed by FEM in order to identify the main cause of failure of blade row. It is found that the stress of root's hole is highest in comparison with other parts from the result of the steady stress analysis. Also, the two dangerous frequencies which is related to the resonance condition are found in the interference diagram. one is 1,516 Hz which is related to the operating speed. The other is 2,981 Hz which is related to the 1 nozzle passing frequency. The dynamic stress analysis is per-formed to identify more accurate root cause for failure of blade row. It is confirmed that the dynamic stress of the latter is higher than one of the former. From these results, it is concluded that the former has deeply something to do with the failure of blades more than the latter. Based on versatile investigation and deliberation, the change of blade's grouping is determined to avoid the resonance condition with the operating speed. After the blade grouping is changed, the former frequency vanish completely but the latter is still in existence in the interference diagram. Fortunately, It is confirmed that the dynamic stress of the new blade grouping is lower than one of the old blade grouping. 2 years has passed since modification and the LP turbine is operated well without failure so far.

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Pathology and Classification of Focal Segmental Glomerulosclerosis (초점성 분절성 사구체 경화증의 병리와 분류)

  • Kim, Yong-Jin
    • Childhood Kidney Diseases
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    • v.16 no.1
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    • pp.21-31
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    • 2012
  • Focal segmental glomerulosclerosis (FSGS) is the name of the primary glomerular disease as well as the terminology to describe the secondary phenomena of any other glomerular diseases. It is characterized by sclerosis, hyalinosis, foam cell infiltration, vacuolar change of podocytes, and halo formation in the glomerulus. Throughout the interstitium, lymphocytes infiltration, tubular atrophy and vascular changes are accompanied. Occasionally, IgM and/or C3 depositions are noted in the sclerotic areas. Electron microscopically, diffuse effacement of foot processes are seen in non-sclerotic area like minimal change disease. Podocyte injury patterns including vacuolar changes are frequently examined. Recently, Columbia group has suggested morphologic classification of FSGS and they demonstrated very good prognosis of tip lesion and poor prognosis of both collapsing and cellular types. However, the pathogenetic classification has been suggested by others; hyperfilteration, podocyte injury, genetic lesions etc. Further studies are necessary to understand and treat this disease.

Strategies to Attract Transshipment Container Cargos from/to China by Korea Ports (우리나라 항만의 대중국 환적화물 유치방안에 관한 연구)

  • 정태원;곽규석
    • Journal of Korean Society of Transportation
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    • v.20 no.2
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    • pp.7-16
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    • 2002
  • Rapid growth rate of container traffic in China has caused the fierce competition to attract Trans-shipment Container Cargos from/to China among competitive ports in Asia. Therefore, this paper aims to suggest some strategies to attract them from/to China by Korea ports. To do so, it evaluates the preference of important ports in the competitive situation and the competitiveness of important ports in Asia, and finally proposes the relative order of important factors. Based on the evaluation of it, Both the Pusan and the Kwangyang ports have to strengthen port facility to attract move traffic and in detail, reinforce the number of berth, yard areas and handling equipment. they also have to provide high qualify of services to deliver cargos in time. not being damaged and swiftly response to shipowner and shipper's claim.

Toe to Finger Transfer in Traumatic Amputated Index Finger (외상성 시지 결손 환자에서 족지를 이용한 수지 재건술)

  • Lee, Kwang-Suk;Park, Sang-Won;Kang, Oh-Yong;Choi, Yong-Kyung
    • Archives of Reconstructive Microsurgery
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    • v.2 no.1
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    • pp.7-12
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    • 1993
  • Traumatic loss of the fingers present significant functional disability and the index finger is an important component of hand function. Since 1900, many attempts and efforts have been done in reconstruction of amputated fingers with toes. Authors clinically analyzed 8 cases of toe-to-finger transfer in traumatic amputation of the index finger to be followed for more than one year at Korea University Hospital from August 1982 to December 1991. The results were as follows: 1. The most common cause of injury was mechanical accident in 7 of 8 cases. 2. Average interval between injury and operation was 8 year 3 months. 3. Average operation time was 5 hours 58 minutes and average ischemic time of transferred toe was 1 hour 52 minutes. 4. Skin flaps have survived in 7 of 8 cases, and the functional results in 6 of 8 cases were over than fair.

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Association between cardiovascular disease and periodontal disease prevalence (치주질환에 의한 심장질환 발생의 관련성)

  • Jeong, Mi-Ae;Kim, Jee-Hee
    • Journal of the Korea Convergence Society
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    • v.2 no.4
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    • pp.47-52
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    • 2011
  • Periodontal disease is a common inflammatory disorder that is being considered as a risk factor for atherosclerotic complication. Recent epidemiological evidence also supports that its potential association with increased blood pressure levels and hypertensive prevalence. Data from cross-sectional studies suggest that in hypertensive patients periodontal disease may enhance the risk and degree of target organ damage. So dental infections have been associated with cardiovascular diseases. There are potential pathophysiologic links between hypertension and periodontits. The role of the inflammatory pathway include C-reactive protein(CRP). CRP is an inflammatory mediator that has been shown to predict the development of hypertension independently of baseline BP and traditional risk factors, has been consistently reported as at least mildly elevated in patients with periodontal disease. Reactive oxygen species produced by locally infiltrating neutrophils participate in periodontal tissue destruction. Periodontits can lead to inflammatory responses in the atrial myocardium, which disturbs the structural and electrophysiologic properties of the atrium and facilitates atrial fibrillation in the animal experiment.

A implement of blackbox with in vehicle network data and the external sensor data (차량내부정보와 외부센서를 사용한 블랙박스 구현)

  • Kim, Jang-Ju;Jang, Jong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.11
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    • pp.2471-2477
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    • 2010
  • lately, vehicle blackbox increasing importance and usability Is needed accuracy and variety of information. because, blackbox help to analyze the exact cause of the accident and use as objective evidence in vehicle-related crime. In the paper, to overcome the limitations of the existing black box, use various sensors and vehicle information blackbox store current state of the vehicle with OBD-II protocol using vehicle state information and store exact current location and direction information of the vehicle with Gyro sensor and GPS and use global time of GPS for synchronization of information. In addition, blackbox back the information up with wifi. because, when blackbox damaged, dirvers were able to verify the information.