• Title/Summary/Keyword: Rupture rate

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A Study on the Utilization for Living Products and Properties of Betula platyphylla Laminated Wood Manufactured by Pressing and Heating (가압.가열처리한 자작나무 적층재의 물성과 생활용품 활용방안 연구)

  • Shin, Rang-Ho;Kwon, Jin-Heon
    • Journal of the Korea Furniture Society
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    • v.25 no.2
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    • pp.96-103
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    • 2014
  • The objective of this study was to increase the utilizability of domestic thinning and small diameter wood as applying in pattern design which can be used in interior decoration, wood craft and wood furniture, and in developing the designs of furniture and household items. We investigated the physical and mechanical characteristics of Betula platyphylla Wood by pressurization and heat treatment. Color change is clear, and the wood density is increased with increasing pressing rate. The compressive strength, modulus of rupture and modulus of elasticity in bending strength are decreased as heating time is increased after pressing. However, shrinkage is improved after pressing and heating.

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Surgical Treatment of Mitral Valvular Disease (승모판막질환의 수술)

  • 이인성
    • Journal of Chest Surgery
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    • v.12 no.2
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    • pp.127-134
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    • 1979
  • During the 4 years period to be reported, 34 operations were performed on the mitral valve in the department of Thoracic and cardiovascular surgery, Korea University hospital, from Aug. 1975 to April 1979. At the first 1-year period, the closed technique was used in 12 patients. After that, open-heart surgery was used routinely; 8 patients had open mitral commissurotomy and 14 patients had valve replacement. There were 18 men and 16 women with sex ratio of 1.1: 1. The age of the patients varied widely from 18 years of the youngest to 46 years of the oldest-average aged of 32.5 years. All had symptoms and the mean duration of symptoms was 6 years and 1 month. Preoperative atrial fibrillation was 47% and embolizations were in 3 of 34 patients. The operative mortality was none for the closed and 14% for the open technique combined rate of 9 per cent which were valve thrombosis, brain embolism and left pulmonary vein rupture in deauriculization. But surviving patients undergoing open heart surgery enjoyed symptomatic benefits comparable to these of the patients of closed.

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THE EFFECTS OF PROSTAGLANDINS AND INDOMETHACIN ON OVULATION IN THE PERFUSED FOWL OVARY

  • Tanaka, K.;Higuchi, T.;Tawarazumita, M.;Hertelendy, F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.1
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    • pp.29-32
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    • 1992
  • The effects of prostaglandins (PG) and indomethacin, a PG synthesis inhibitor, on ovulation in the perfused fowl ovary were studied. Laying hens were killed by cutting the jugular vein 18-19 h before expected ovulation of the second follicle of a clutch sequence. The cannulated ovary was dissected free and connected with a recycling perfusion apparatus. Agents to be studied for their effects on ovulation were added to the perfusion fluid. $PGF_{2{\alpha}}$ at 0.1 and 1 mg/l induced ovulation, with a success rate of 25% and 30%, respectively. The same doses of $PGE_2$ were effective at 60% and 63%, respectively. Indomethacin partially blocked gonadotrophin-induced ovulation. It is suggested that PGs may play a supportive role in the process of follicular rupture in the domestic fowl.

Creep Life Prediction of SUS 316L Stainless Steel (STS 316L 스테인리스강의 크리프 수명예측)

  • Yoon, Jong-Ho;Hwang, Kyung-Choong
    • Transactions of the Korean Society of Automotive Engineers
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    • v.14 no.2
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    • pp.16-22
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    • 2006
  • Stainless steel has widely been used in various industrial fields because it has high corrosion resistance. But, we have little design data about the creep life prediction of SUS316L stainless steel. Therefore, in this study, a series of creep tests and study on them under 16 constant stress and temperature combined conditions have been performed to get the creep design data and life prediction of SUS316L stainless steels and we have gotten the following results. First, the stress exponents decrease as the test temperatures increase. Secondly, the creep activation energy gradually decreases as the stresses become bigger. Thirdly, the constant of Larson-Miller parameters on this alloy is estimated about 10. And last, the creep rupture fractographs show the intergranular ductile fracture with many dimples.

A Study on FE Analysis For Improvement of Backward Impact Extrusion Process (후방 충격압출 공정개선을 위한 유한요소 해석기법 연구)

  • 정상원;정용호;김규하;조규종
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.641-645
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    • 2002
  • In case of aluminum-cased battery, The ratio of height and base of square is generally above the ten times, square-shaped and problem of non-axis symmetry. It is typical model to set up the analysis method of finite element. The reliable analysis of finite element method is suggested, which is used to investigate the possibility that multi-stage deep drawing and ironing used currently is replaced by backward impact extrusion favorable in the respect of cost production and productivity. The influence of parameter was analyzed and compared, which was considered to analyze the process of large deformation plasticity such as extrusion. Die and billet was made as the same shape of finite element model. The results of experiment show good forming without the rupture and wrinkles with the optimum velocity 100mm/sec obtained by analysis.

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Clinical Analysis of Esophageal Perforation by Esophageal Foreign Body (식도이물에 의한 식도천공의 임상적 고찰)

  • 김범규;송민성;안성기;김진평;전시영;장인석
    • Korean Journal of Bronchoesophagology
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    • v.9 no.2
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    • pp.44-48
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    • 2003
  • Rupture of the esophagus is an uncommon condition that can be a formidable challenge to treat. Unless early treatment is applied, life-threatening complications, such as mediastinitis, sepsis, occurs and continue to be associated with a mortality rate of more than 20%. Definitive repair of esophageal perforation is considered the preferred treatment in the past. In the present study, conservative treatment acquired a good results by help of the development of antibiotics and nutritional supportive methods. Iatrogenic causes constituted most of the injuries, followed by external trauma, spontaneous, ingested foreign bodies, and malignancy. The incidence of perforation following ingestion of foreign bodies is very rare, so recommendations regarding treatment remain controversial. We analyzed the course of 31 patients with esophageal perforation by foreign bodies, concentrating on the diagnostic & treatment delay and methods of treatment, complications.

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Experimental Study of the Joint Movement Responsiveness Performance to the One-Component Silicon Sealants at Curing Phase (경화단계에서의 1성분형 실리콘 실란트의 거동대응성능에 관한 실험적 연구)

  • Son, Jong-Won;Ono, Tadashi
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.11a
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    • pp.63-64
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    • 2014
  • In this study, we has a purpose to estimate the joint movement responsiveness performance for the domestic products of one-component structural silicon sealants. For this purpose, we make a comparative study for the four domestic products focused on tensile properties after allowed the cyclic-movements for three days at initial step of curing phase. A joint movement range ±10% and the rate of compression and extension 3.2mm/h were assumed in those tests. As a result, the large space were induced inside the sealant by rupture, and then adhesion and cohesion failures were caused by stress concentration. The tensile properties were reduced by 15~60% in comparison with physical properties. In this case, the generating defect was caused and the service-life was decreased. Thus, further researches as relationship of test condition and products properties on this behavior would be studied.

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Stability and drug release properties of liposomes containing cytarabine as a drug carrier

  • Kim, Chong-Kook;Park, Dong-Kyu
    • Archives of Pharmacal Research
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    • v.10 no.2
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    • pp.75-79
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    • 1987
  • Liposomes were studied as a drug delivery system. Multilamellar vesicles, small unilamellar vesicles and large unilamellar vesicles containing cytarabine were prepared using egg yolk lecithin and cholesterol. Large unilamellar vesicles showed the highest encapsulation efficiency of all and their encapsulation efficiency increased as the buffer volume decreased. Cholesterol increased the stability of liposomal drug products as drug carriers and reduced the permeability of drug across the liposomal membrane. The release rate of cytarabine increased with incubation temperature and decreased with cholesterol incorporation in liposomal membrane. The release mechanism of cytarabine from large unilamellar vesicles in vitro was chiefly due to simple diffusion across the liposomal membrane rather than liposomal rupture.

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Sensitivity Analysis of Seismic Source Models for Probabilistic Seismic Hazard Analysis (확률론적 지진재해도 분석을 위한 지진원 모델의 민감도 분석)

  • 김연중;전정윤;김태균
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.09a
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    • pp.36-45
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    • 2003
  • Sensitivity analyses for several seismic source models were studied. For the area sources, the hazard is steeply decreasing with the source-to-site distance. Hazard is decreasing when the area of the source is increasing with fixed annual rate. For the fault sources, the fault length, distance from a site and dip angle of near fault show very sensitive effect to seismic hazard. But the various magnitude-rupture length relationships show effect to seismic hazard slightly. For the fault source with small magnitude, the exponential model is preferred rather than the characteristic model to the magnitude-recurrence law.

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Resuscitative Endovascular Balloon Occlusion of the Aorta for an Iliac Artery Aneurysm: Case Report

  • Chang, Sung Wook;Chun, Sangwook;Lee, Gyeongho;Seo, Pil Won
    • Journal of Chest Surgery
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    • v.54 no.5
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    • pp.429-432
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    • 2021
  • Isolated iliac artery aneurysm (IAA) is rare, but can be fatal. Emergency surgery is performed in cases of hemorrhagic shock due to a suddenly ruptured IAA, which may have a high mortality rate because of massive non-compressible torso hemorrhage (NCTH). Recently, resuscitative endovascular balloon occlusion of the aorta (REBOA) has been accepted as an alternative to aortic cross-clamping via open thoracotomy to achieve hemostasis in trauma patients with profound shock due to NCTH and is considered an emerging bridging therapy for damage control. However, there is limited information on the use of REBOA in non-trauma patients with shock. Herein, we describe a patient with impending cardiac arrest due to isolated ruptured IAA, in whom perioperative bleeding was successfully controlled by REBOA.