• 제목/요약/키워드: severe condition

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유한요소법을 이용한 원통형 강편의 자유단조 해석 (Analysis of Free Forging of Cylindrical Billets by Using finite Element Method)

  • 정동원
    • 한국해양공학회지
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    • 제16권6호
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    • pp.49-54
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    • 2002
  • The Finite Element Method is applied to the determination of the deformed bulge profile and strain distribution during upset forming of cylindrical billets. From the results of simulation, the bulging along the z-axis becomes more severe with increasing eight reduction, and with increasing friction at the die-material interface. The present method can be used for the simple prediction of the deformed shape and strain distribution in upset forging of cylindrical billets with dissimilar fictional conditions at the die-material interfaces.

포/포탑 구동 시스템의 제어기 설계에 관한 연구 (A study on the controller design of gun/turret servo system)

  • 이석재;정오진;이교일
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.718-723
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    • 1992
  • A hydraulic gun/turret servo system requires fast and robust controller performance because of severe operating condition and precise target tracking objective. Digital controllers are able to satisfy this requirement due to high speed electronic device. The purpose of this study is to compare with pre-EPU with new-designed optimal, adaptive controllers by simulating nonlinear hydraulic simulation program. The designed digital controller shows good tracking performance and robustness to disturbance.

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충격식 피로시험기 개발 (Development of Impact Fatigue Test Machine)

  • 남용윤;신병천;홍석균;이성우
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.1154-1160
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    • 2000
  • This paper reports the development of a special impact fatigue test machine for high pressure vessels. The targeted vessels are subjected to shock pressures equivalent of explosions. This severe loading condition brings many difficulties to the design of test machine. Unfortunately, there are very rare such test machine in the world, and more worse, the machine is not opened and sold.

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Angle씨 Ⅰ급 부정교합의 치험례 (A CASE REPORT OF ANGLE'S CLASS I MALOCCLUSION)

  • 김성남;최선웅;서정훈
    • 대한치과의사협회지
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    • 제13권12호
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    • pp.1135-1139
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    • 1975
  • A boy aged 13 years 5 months, had a Angle's clss I malocclusion characterized by severe anterior crowding. Molar relationship was neutroclusion, incisor overbite was 4mm, incisor overjet was 3mm. The patient underwent extraction of four first premolars and was treated with a multi-banded light force system. On the process of the orthodontic treatment, the teeth, obtained functional occlusion. The result of treatment was very satisfactory; color, vitality and mobility were normal, periodontal condition was good and the cosmetic result was excellent.

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전력용 변압기의 단락강도 해석 (Computational Analysis of Short-Circuit Stresses in Power Transformer Windings)

  • 최영길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.147-150
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    • 2002
  • This paper describes the work performed by computer simulation to achieve a satisfactory method of predicting the short circuit withstand strength of transformer which, may be too big for test due to physical or economic reasons. In fact, the windings of power transformer are subjected to extremely severe stresses under short-circuit condition. From our work, however, were computed such stresses as buckling, tending and compression occurring in transformer windings.

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An Eigenvalue Method Used in Impedance Computed Tomography

  • Li, Mingji;Uchiyama, Akihiko
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.85-88
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    • 1998
  • We have developed an eigenvalue method for impedance computed tomography to improve the ill-conditioning problem. We have compared the performance of this method and the balancing method by computer simulations. As a result, it was proved that this method is better than the balancing method very much. It was found that the initial value condition is not so severe to obtain good images.

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Treatment of chronic bronchopleural fistula and recurrent empyema using a latissimus dorsi myocutaneous flap: a case report and literature review

  • Kang, Byungkwon;Myung, Yujin
    • Archives of Plastic Surgery
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    • 제48권5호
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    • pp.494-497
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    • 2021
  • Bronchopleural fistula is a severe complication with a high mortality rate that occurs after pulmonary resection. Several treatment options have been suggested; however, it is a challenge to treat this condition without recurrence or other complications. In this case report, we describe the successful performance of a pedicled latissimus dorsi myocutaneous flap transfer, with no recurrence or donor site morbidity.

The siren noise of ambulance is killing me!

  • Ko, Kyung-Ja;Kim, Hyung-Min
    • 셀메드
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    • 제9권2호
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    • pp.4.1-4.1
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    • 2019
  • Noise pollution is present all places and affects health negatively. It feels more like that to the patients. When the patient in severe condition is being taken to the emergency room, we have to overcome the siren noise of ambulance. Patients are also more terrified by the sound of sirens. Instead of siren noise, why not use the sound of Buk (Korean drum) for patient, citizens, and social elements including animals and plants?

수중 보수재료의 부착강도 및 내구성능 평가 (Evaluation of Bond Strength It Durability of Repairing Materials for Underwater Concrete Structures)

  • 손영현;임치중;김완상;김세준;서정우;박영석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.829-834
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    • 2002
  • Recently, research and development for a number of repairing material like an epoxy-based material and polymer-cementitious material as well as anti-washout underwater concrete have been carried out. But, the study on tile materials for the concrete structure exposed to a wetted condition is at a standstill and there are not any suitable reference data at a repairing work for the concrete structure at a splash as well as a structure under severe moisture condition. In this study, the material, called as “ceramic metal”, with an excellent mobility and plasticity as well as with a high bond strength and durability of freezing-thawing resistant properties under any environmental conditions was developed. And, the experimental evaluations for the utility wert widely performed.

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변화하는 단면의 문형구조물의 진동계산에 관한 연구 (A study on the vibration calculation method of portal frame structure with variable sections)

  • 조용수;전효중
    • Journal of Advanced Marine Engineering and Technology
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    • 제9권3호
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    • pp.214-224
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    • 1985
  • In this paper, some theoretical equations are derived to calculate natural frequencies and their modes of a portal type derrick system and developed a computer program to carry out their calculations. The ship's structures, such as funnels, upper decks, engine structures, shaft systems suffer local vibrations of the ship. The exciting forces of vibrations are induced by the bearing force and the surface force of propeller or by the main engine. For solving the vibration problem of riggings like the derrick system the natural frequency of its system must be exactly estimated as far as possible and its resonance condition must be kept out of the normal engine operating speed range. When some severe resonances are encountered after the ship's launching, it may be required a tremendous cost to amend their condition. An experimental model of the portal type derrick is made, which is composed of two posts and a truss. This experimental model is excited by an electrical-magnet, and its vibration responses are found out. The calculating results of the model by the developed computer program are compared with those of measured values of model experiment, and they show fairly good agreements.

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