• Journal of the Korean earth science society
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• v.33 no.6
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• pp.544-553
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• 2012

A simple experimental method was developed to help students understand the effect of the Coriolis force on typhoon genesis and movement. It consists of rotating tanks with and without a sloping bottom, and a small stirrer to produce cyclonic typhoon-like vortices by locally stirring the water. Vortices were able to last for more than 3 minutes without dissipation in the rotating tank. However, vortices were hardly maintained without rotation, and would rather disappear as soon as the stirrer stopped mixing. Since the dynamical properties of the rotating water are similar to those of the atmosphere influenced by the Coriolis force, the experiments show that the Coriolis force is indispensable to the typhoon genesis. When the tank had both the sloping bottom and rotation, vortices would move in a particular direction. Considering the topographical beta effect, this result indicates that typhoons are drifted not only by the steering wind but also by the meridional gradient of the Coriolis force. The methodology developed in this study, would be useful for both students and teachers to better the relationship between the Coriolis force and the typhoon genesis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.5
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• pp.75-82
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• 2015

An experimental study has been carried out to examine development length effects for high strength headed deformed bars. Current design codes limit the specified yield strength of headed bars to 400 MPa. Such the limit is due to the lack of experimental studies on headed bars made of high strength materials. Thus a test program was planed with headed bars with the yield strength of 600 MPa. The threaded head type with head shapes of round plate and circular cone was selected in this study. The experimental variables were development length, number of bars, and head shape. Specimens were classified into L-type and S-type depending on the development length. The development length of L-type was computed according to the design code without considering the limit. S-type specimens had shorter development lengths than the L-type. Further classification was made depending on the shape of heads. A-types have the head shape of round plate and B-types have the shape of circular cone. Three L-type specimens were fabricated with the variable of number of bars (1, 2, and 3). Four specimens for each of SA and SB types were made with development lengths of 50%, 45%, 40%, and 35% compared with L-type. Pullout tests was carried out with 11 specimens. The test results were compared with computed strengths with the design code equations (Appendix II). Based the current studies, it can be said that high strength headed deformed bars used in this study be able to provide such strengths computed with the current design code without considering the yield strength limit.

• The Journal of the Korean dental association
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• v.58 no.6
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• pp.364-376
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• 2020

Internal derangement of the temporomandibular joint (TMJ) is condition in which articular disc has become displaced from its normal functional relationship with the mandibular condyle and the articular portion of the temporal bone. Common types of internal derangement include disc displacement with reduction (with or without intermittent locking), and disc displacement without reduction (with or without limited opening) classified according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Treatment varies depending on diagnosis. Therefore, differential diagnosis should be made for appropriate treatment.

• Journal of Chest Surgery
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• v.17 no.2
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• pp.315-320
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• 1984

A vascular complication caused by lumbar disc surgery is not infrequent till recently after the report by Linton and White in 1945. Thereafter, many reports about the accidental injuries to the great vessels anterior to the lumbar area had been reported. In June, 1982, we experienced one case of arteriovenous fistula between right common lilac artery and inferior vena cava which was corrected surgically. The arteriovenous fistula caused by lumbar disc surgery and its review of the literature and presented.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.486-491
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• 1998

본 연구에서는 충돌면의 형상에 따른 고속 원형 충돌제트의 불안정 모드를 밝히기 위하여 우선 충돌면의 형상에 따른 주파수 특성을 비교하고자 하였다. 이를 위해 충돌면이 제트의 직경보다 작은 원판(small plate)과 제트의 직경보다 큰 구멍(hole)의 2가지 경우에 대하여 실험을 하였고, 평판 충돌음에 대한 연구결과와 비교 검토하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.295-301
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• 2001

An investigation into asymmetric vibrations of a clamped circular plate under a hannonic excitation is made. We examine a primary resonance, in which the frequency of excitation is near the natural frequency of an asymmetric mode of the plate. We found not only a response having the form of standing wave but also one having the form of traveling wave, which was not observed by Sridhar, Mook and Nayfeh(1978; Journal of Sound and Vibration 59(2), pp. 159-170).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.533-538
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• 2002

This research demonstrates the transient response of a head disk assembly subjected to a half-sine shock pulse in the axial direction. In case of disk analysis, the numerical method presented by Barasch and Chen is used. Galerkin method is used with mode shape by numerical method. head-suspension system is modeled by the cantilever in order to get simulation results. Simulation results about total system of HDA are calculated by Runge-Kutta method.

• Journal of Chest Surgery
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• v.15 no.4
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• pp.428-431
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• 1982

A vascular complication caused by lumbar disc surgery is not infrequent till recently after the first report by Linton & White in 1945. In October 1980, we experienced one case of arteriovenous fistula following lumbar disc surgery in the department of thoracic surgery, CAFGH. The A-V fistula was situated between left common iliac artery and vein, which was confirmed by angiography easily. The A-V fistula was corrected surgically by Taylor`s method successfully without complication.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.185-186
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• 2000

순환여과식 양식 시스템은 주위 환경에 영향을 최소로 할 수 있는(Ackefors and Enel, 1992) 환경친화적 양식 방법으로, 대부분의 순환수를 버리지 않고 재 이용하기 위해서는 사육시스템 내 생성된 어류 노폐물을 처리하기 위한 인위적인 처리 장치가 필수적이다. 이들 노폐물 중 암모니아 농도는 시스템 내 생산성을 제한하는 인자로서, 생물여과조를 이용한 수질관리가 이루어지고 있다. (중략)

• Proceedings of the KIEE Conference
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• 2004.10a
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• pp.15-17
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• 2004

This paper deals with design and manufacture of rotational round plate type Permanent magnet linear synchronous motor. The magnetic flux density and thrust force characteristics is calculated by using analytical method and 2-D finite element analysis.