• Title/Summary/Keyword: cushion

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Development of Determination Criteria Installing Crash Cushion on Freeway Off-Ramp (고속도로 진출램프 부근의 충격흡수시설 설치여부 판단기준 개발에 관한 연구)

  • 하태준;박제진;오재철
    • Journal of Korean Society of Transportation
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    • v.20 no.7
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    • pp.107-116
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    • 2002
  • Crash Cushion is a kind of safety facilities on roadside which acts the role of absorbing impact energy when vehicles are driven out of normal route such as Gore area of freeway off ramp. Criteria for severity index considering accident occurrence possibility are needed to have strong effect on installing the facilities. However, present criteria for establishing crash cushion design do not include such processes. Therefore, the paper presents two kinds of study to develop criteria for severity index. First of all, development of accident forecasting model on freeway off ramp is presented. The module is a relationship between accidents and road environment by negative binomial distribution (NB) which is called to reflect very well quality of accidents at Gore of crash cushion installed freeway Secondly, freeway exiting behavior model is developed because the human factor is the most important one. However, many literatures have shown between road environment and accidents which are more quantitative than human factor. The study supposed advanced process steps on actual freeway and analysed correlation between variables and accidents. The criteria for severity index is presented to determine whether to install or not by benefit cost analysis for each module. The standard for severity index will help to determine whether to install the crash cushion or not and to estimate severity for freeway and off ramp.

Surgical Treatment of Incomplete Endocardial Cushion Defect: 2 Cases Report (심장내막상결손증의 외과적 치료: 2예 보고)

  • 송요준
    • Journal of Chest Surgery
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    • v.7 no.1
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    • pp.101-108
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    • 1974
  • Repair of incomplete endocardial cushion defect was accomplished in two cases in September 1973 in this department. In each case a low atrial septal defect and a cleft of mitral septal cusp were found. Interrupted suture repair on the cleft mitral cusp and closure of the atrial septal defect with dacron patch were done successfully. Rigg-Kyvsgaard bubble oxygynator and Sigma motor were utilized for extracorporeal circulation. Follow up study, six months after discharge, revealed satisfactory results.

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A Study on Nonlinear Pneumatic System Characteristics (비선형 공기압시스템 특성연구)

  • 박재범;김동수;김형의;염만오
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.826-830
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    • 1996
  • The pneumaic systems are widely applied to chemical factory of fire dangry and factory automation. by using compressed air, it is difficult to dynamics action analysis that the pneumatics system acts to nonlinear motion through orifices and valve flow. This paper was studied to a nonlinear chararistics of pneumaic spring, damper and absorber of pneumaic cushion cylinder.

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Postoperative Follow up Study in ECD (심내막상 결손증 술후 추적 관찰에 관한 연구)

  • 류지윤
    • Journal of Chest Surgery
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    • v.27 no.3
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    • pp.196-201
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    • 1994
  • Endocardial cushion defect is a rare congenital heart disease. From September 1985, we experienced 20 cases of endocardial cushion defects and postoperative follow up was taken.We reviewed preoperative clinical data, echocardiography, cardiac cath data, operative method & time. After operation, we performed echocardiography and examined mitral valve function & integrity of patch closure sites. Postoperative follow up was taken regularly & follow up period was from 2 month to 91 months. Several postoperative complications were overcome with adequate treatment. There were 3 cases of early death and mortality rate was 15% [3/20].

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Prediction Model of Allowable Pile Depth, Duration of Flesh Fruit and Optimum Thickeness of Packaging Cushion (과실포장용(果實包裝用) 전충물(填充物)의 적정(適正)두께 예측(豫測)과 과실(果實)의 허용산적(許容山積)높이 및 산적기간(山積期間) 예측모형(豫測模型))

  • Kim, M.S.;Park, J.M.
    • Journal of Biosystems Engineering
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    • v.16 no.3
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    • pp.281-289
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    • 1991
  • During the storage and transport of fruits in the bulk state, significant damage by dead load may occur. To reduce such damage, the prediction model of allowable pile depth, duration and optimum thickness of packaging cushion for fruits was developed in this study. From the preliminary experiment and some assumptions, the derived equations were verified to be a good prediction of the above three parameters.

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Development of Crash Cushion by Computer Simulation (컴퓨터 시뮬레이션을 통한 충격흡수시설의 개발)

  • Kim, Dong-Sung;Kim, Kee-Dong;Ko, Man-Gi
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.513-516
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    • 2008
  • The development of crash cushions is finally completed by full-scale vehicle crash tests. Since the current development of crash cushions is achieved by numerous repeated full-scale vehicle crash tests based on empirical and irrational methods, it requires a great amount of costs. In this research, the more rational procedure based on prototype design by static tests and computer simulation is suggested and it can minimize the number of full-scale vehicle crash tests.

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A study on the fabrication methods of rough diamond according to their shapes (bruting) (다이아몬드 원석의 외형에 따른 가공방법에 관한 연구(모형))

  • 최덕환;김세환;최종건
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.1
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    • pp.46-50
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    • 2003
  • This paper is a study on the method that it is bruting a peace of a rough diamond with keeping the maximum volume of it. When a diamond will be bruting, how to keep the maximum diameter of one is very important because of its own characteristics that include shapes, mineral characteristics, and so on. In the middle of bruting. concentrating on the work is also required because girdle will be break down. We tried to bruting with gaining maximum diameters of rough diamond. As the result. an octahedron is made into the round shape with size $6.75\times 6.75\times 3.83$ mm , a dodecahedron the cushion shape with size $6.86\times 6.86\times 3.95$mm , a fancy the marquise with size $6.92\times 3.78\times 3.46$mm . Their rates of loss are round brilliant 24.5%, cushion barion 15.5 %, and marquise 18.7 %, respectively.

Measurement of Maneuverability in the Restricted Area by Numerical Model Ship (수치 모형선에 의한 제한수역에서의 조종성능 측정)

  • Park, Byung-Soo;Kim, Jong-Hwa;Kim, Cheog-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.4
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    • pp.363-367
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    • 2009
  • The ship maneuverability is changed by the effects of the bank cushion and the squat in the restricted water area. It is difficult to test the ship maneuverability by the real ship in the restricted water area because of ship's safety. In this study, a numerical model ship was used to simulate the ship's motion and to get information about the bank cushion and the squat in the restricted water area. The less apart from the quay the ship ran, the more ship's heading changed. The greatest change of ship's heading was $22.37^{\circ}$ when a ratio of the length between ship and quay to ship's breadh(=D/B) was 0.2. The squat of the ship was greater in shallower water and at faster speed. The greatest squat was 0.29m when a ratio of water depth to ship's draft(H/d) was 1.25 and ship's speed was 8 knots, the reduced speed was found to be the most important factor in the shallow water area for safety of the ship.

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