• Title/Summary/Keyword: 파열 강도

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A Parameter Study on the Shear Failure Behavior of Post-installed Set Anchor for Light Load (저하중용 후설치 세트앵커의 전단파괴거동에 관한 매개변수 연구)

  • Um, Chan-Hee;Yoo, Seung-Woon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.3
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    • pp.55-63
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    • 2015
  • Post-installed concrete set anchors are installed after the concrete hardened. These anchors increasing usage in development of construction equipment and flexible construction. The anchor loaded in shearing exhibits various failure modes such as steel failure, concrete failure, concrete pryout, depending on the shear strength of steel, the strength of concrete, edge distance and anchor interval, etc,. In this study, the objective is to investigate the effects of the variations like anchor embedment depth, edge distance and concrete strength on experimental and finite element analysis of shear failure behavior of post-installed concrete set anchor for light load embedded in concrete. The results of embedment depth experiments show that concrete strength has much affection on the shallow embedment depth. Concrete strength has no much affection with anchor interval and edge distance parameter and both experimental results occurred same failure mode. By comparing the experimental results that occurred steel failure mode show that as strong as concrete strength are the displacement results are small.

Clinical Experience of Abdominal Aortic Aneurysm (복부 대동맥류 수술의 임상적 고찰)

  • Kwak, Young-Tae;Lim, Sang-Hyun;Lee, Sak;Yoo, Kyung-Jong;Chang, Byung-Chul;Kang, Meyun-Shick;Hong, Yoo-Sun
    • Journal of Chest Surgery
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    • v.36 no.4
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    • pp.261-266
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    • 2003
  • Background: Surgery of abdominal aortic aneurysm revealed high operative mortality. We reviewed our 11-years' experiences of abdominal aortic aneurysm operation and wish to obtain information on the treatment. Material and Method: From Jan. 1990 to Dec. 2000, 48 patients were operated due to abdominal aortic aneurysm in Yonsei Cardiovascular Center Mean age was $62.8{\pm}12.7$ and there were 40 males and 8 females. Among 48 patients, nine patients had ruptured abdominal aortic aneurysm, and mean aneurysm diameter of non-ruptured cases was $8.8{\pm}2.4$cm. Result: There were 6 early deaths, and early mortality was 12.5%. Among 9 patients of preoperative aneurysm rupture, three patients died (33.3%), and among 39 patients of non-ruptured cases, 3 patients died (7.7%). Among preoperative variables, age (p<0.05), preoperative BUN level (p<0.05), and DM (p<0.05) were risk factors of early mortality. Among discharged 42 patients, 40 patients were followed up (f/u rate=95.2%) and mean follow up was $3.6{\pm}0.2$ years. During follow up periods, five patients died (late mortality=11.9%), and Kaplan-Meier survival analysis revealed $81.7{\pm}7.6$% survival rate at five and ten year. Linealized incidence of graft related event was 3.53% per patient-year. Conclusion: Surgical mortality of ruptured abdominal aortic aneurysm was higher than non-ruptured cases; therefore, early resection of the aneurysm can decrease the surgical mortality.

Behavior of 550MPa 43mm Hooked Bars Embedded in Beam-Column Joints (보-기둥 접합부에 정착된 550 MPa 43 mm 갈고리철근의 거동)

  • Bae, Min-Seo;Chun, Sung-chul;Kim, Mun-Gil
    • Journal of the Korea Concrete Institute
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    • v.28 no.5
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    • pp.611-620
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    • 2016
  • In the construction of nuclear power plants, only 420 MPa reinforcing bars are allowed and, therefore, so many large-diameter bars are placed, which results in steel congestion. Consequently, re-bar works are difficult and the quality of RC structures may be deteriorated. To solve the steel congestion, 550 MPa bars are necessary. Among many items for verifying structural performance of reinforced concrete with 550 MPa bars, the 43 mm hooked bars are examined in this study. All specimens failed by side-face blowout and the side cover explosively spalled at maximum loads. The bar force was initially transferred to the concrete primarily by bond along a straight portion. At the one third of maximum load, the bond reached a peak capacity and began to decline, while the hook bearing component rose rapidly. At failure, most load was resisted by the hook bearing. For confined specimens with hoops, the average value of test-to-prediction ratios by KCI code is 1.45. The modification factor of confining reinforcement which was not allowed for larger than 35 mm bars can be applied to 43 mm hooked bars. For specimens with 70 MPa concrete, the average value of test-to-prediction ratios by KCI code is 1.0 which is less than the values of the other specimens. The effects of concrete compressive strength should be reduced. An equation to predict anchorage capacity of hooked bars was developed from regression analysis including the effects of compressive strength of concrete, embedment length, side cover thickness, and transverse reinforcement index.

Effects of Endoglucanase and Exoglucanase from Trichoderma viride on Brightness and Physical Properties of Deinked Old Newsprint (Trichoderma viride로부터 분리한 Endoglucanase 및 Exoglucanase가 탈묵 펄프의 백색도 및 물리적 강도에 미치는 영향)

  • 김동원;정영규장영훈손기향
    • KSBB Journal
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    • v.11 no.6
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    • pp.718-725
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    • 1996
  • Old newsprint was deinked with endoglucanase, exoglucanase and their various compositions from Trichoderma viride. The yield decreased with an increase in enzyme concentration. Especially, it was the lowest in the treatment of endo-exo mixture(1:1). It may be regarded as a synergistic actions of the cellulase components. The brightness was the highest in pulp deinked with endo-exo mixture(1:1). Maximum brightness was observed when 0.5mg/mL of the endo-exo mixture was used. The physical strength increased with increasing concentration in exoglucanase. But, it decrease with increasing concentration in endoglucanse and endo-exo mixture(1:1). Also, we investigated the yield, brightness and physical strength of endoglucanase in combination with exoclucanase(12:1, 8:1, 4:l, 1:1, 1:4, 1:8, 1:12). Maximal deinking conditions, obtained at a specific optimal ratio of endoglucanase to exoglucanse are as follow ; 12:1 for yield, 12:1 for brightness, 4:1 for tensile strength, 12:1 for bursting strength, and 8:1 for tearing strength. These results indicated that the deinking depended largely upon the action of endoglucanase. Exoglucanase was occupying more than 60% of the total crude cellulase contents. Therefore, the most effective deinking must repress the action of exoglucanase.

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A Case of Spontaneous Hemothorax Associated with Von Recklinghausen's Disease (Von Recklinghausen 병에 동반된 자발성 혈흉 1예)

  • Kang, Mi-Jeong;Chung, Lee-Young;Kim, Su-Jin;Kang, Jung-Hun;Jeong, Gyeong-Won;Park, Dong-Jun;Lee, Jong-Deog;Hwang, Young-Sil
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.4
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    • pp.538-542
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    • 1999
  • Spontaneous hemothorax may be developed as a complication of von Recklinghausen's disease. It is rare but fatal. A 60 year old man with von Recklinghausen's disease was admitted to our hospital because of left chest and shoulder pain. Radiograph of chest showed a massive left pleural effusion. Thoracentesis revealed gross blood. The peripheral angiography was done to determine the source of bleeding and its finding showed intercostal artery aneurysm in left 7th rib. No active bleeding from the aneurysm was seen. The source of the hemothorax was believed to be hemorrhage from rupture of intercostal artery aneurysm. He was inserted chest tube and treated embolization of intercostal artery aneurysm.

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Traumatic Intimal Tearing of the Descending Thoracic Aorta -A Case Report- (외상성 하행흉부대동맥 내막 파열 -치험 1예 보고-)

  • Chang, M.;Jang, J.S.;Kang, M.S.;Cho, B.K.;Hong, P.W.
    • Journal of Chest Surgery
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    • v.13 no.3
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    • pp.269-273
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    • 1980
  • The rupture of the aorta commonly follows major blunt trauma to the thorax. It has markedly increased in recent years, paralleling the rising number of vehicular accidents. The most frequent site of rupture is the area of the isthmus, with the ascending aorta second. The diagnosis of the condition from clinical data is difficult, and aortography is used whenever aortic tear is suspected. We are presenting a case of patient who had intimal tearing of the thoracic aorta with multiple injuries. The patient underwent surgical repair 28 days after injury with left heart [LA-Femoral artery] bypass.

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A Case Report of Intra-articular Bee Venom Pharmacopuncture for Partial Tear of Triangular Fibrocartilage Complex. (삼각 섬유연골 복합체 부분 파열에 대한 관절강내 봉약침 시술 치험 1례)

  • Lee, Kwang-Ho;Ryu, Young-Jin;Sun, Seung-Ho;Kwon, Ki-Rok
    • Journal of Pharmacopuncture
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    • v.12 no.4
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    • pp.127-134
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    • 2009
  • Objective: This case was to report a case of Partial Tear of Triangular Fibrocartilage Complex treated by Intra-articular bee venom Pharmacopuncture. Methods: The patient was treated by Intra-articular bee venom Pharmacopuncture. The Effect of Treatment was evaluated by Visual Analog Scale(VAS) and Modified Mayo Wrist Score(Wrist Score). Results & Conclusions: After Treatment, Patient's VAS decreased and Wrist Score increased. For this results, Intra-articular Bee Venom Pharmacopuncture may be effective for Partial Tear of Triangular Fibrocartilage Complex.

Study on physical property of soft film for greenhouse (시설하우스용 연질필름의 물리적 특성에 관한 연구)

  • 장유섭;김승희;한길수;정두호;김기철
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1995.10a
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    • pp.61-63
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    • 1995
  • 우리나라 원예시설 면적은 현대화, 대형화 사업에 의해 매년 증가되고 있는 추세로 시설의 외피복재도 연질필름에서 유리, PC 등 경질판 피복재로 변화되어 가고 있다. 그러나, 아직도 원예시설의 외피복재는 연질필름이 대부분의 원예시설에 사용되고 있다. 이러한 연질필름의 피복재에 과한 충격강도, 인장, 인열, 신장율 등 물리적 기계적 성질이나 광투과성에 관한 연구가 미진한 실정에 있다. 특히, 시공시 피복재 인장파열, 신장변형 훼손, 충격에 의한 파손 등 뿐만아니라 투광율 등에 관한 많은 문제점이 노출되고 있어 이러한 문제점에 대한 검토가 절실하게 요구되고 있다. (중략)

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백상폐지의 과산화수소 표백에 미치는 활성제의 영향

  • 안병준;백기현
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2001.04a
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    • pp.63-70
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    • 2001
  • Sodium persulfate, prestogen W, prestogen EB, citric acid 및 thiourea의 첨가에 따른 $H_2O_2$ 표백 효과가 연구되었다. Sodium persulfate(1%), Prestogen EB(15.0%)를 $H_2O_2$ 활성제로 첨가하여 표백할 경우 기존 $H_2O_2$ 표백(86.0% ISO)보다 표백 펄프의 백색도가 2-3% ISO 더 증가하였다. $H_2O_2$ 표백 후 thiourea를 첨가하여 표백하는 산화-환원 연속표백(87.9% ISO)에서도 $H_2O_2$ 표백 후 FAS로 2단 표백(88.3% ISO)을 한 경우와 비슷한 백색도를 나타내었다. 한편 표백 펄프의 인장지수, 파열지수 그리고 인열지수는 기존 표백 또는 Prestogen EB를 첨가할 경우 높고 sodium persulfate 첨가에서 가장 낮았다. 산화-환원 연속 표백된 펄프의 강도도 기존 $H_2O_2$ 표백보다 미세하게 낮았다.

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Development of Corrosion Defect Assessment Method for City Gas Pipeline (도시가스배관 부식결함 평가방안 개발)

  • Kim, Cheol-Man;Kim, Woo-Sik;Han, Sang-In;Choi, Song-Chun
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.228-233
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    • 2004
  • The length of city gas pipeline is increasing with expansion of natural gas transmission rapidly. A lot of the expense was paid for repair and maintenance with increasing of pipeline length and the cost of repair and maintenance by the corrosion was the highest. It is necessary to evaluate integrity in case of thickness reduction by corrosion. There are a lot of assessment criteria for corrosion defect in foreign countries but they are not suitable for application in the country directly. In this work, we performed the burst test and the finite element analysis for city gas pipeline, KS D3507 and KS D3631 for city gas transmission, and developed the assessment method of corrosion defect, which is suitable for domestic condition.

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