• 제목/요약/키워드: Diaphragm's Shape

검색결과 23건 처리시간 0.02초

Predicting the stiffness of shear diaphragm panels composed of bridge metal deck forms

  • Egilmez, Oguz O.
    • Steel and Composite Structures
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    • 제24권2호
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    • pp.213-226
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    • 2017
  • The behavior of building industry metal sheeting under shear forces has been extensively studied and equations have been developed to predict its shear stiffness. Building design engineers can make use of these equations to design a metal deck form bracing system. Bridge metal deck forms differ from building industry forms by both shape and connection detail. These two factors have implications for using these equations to predict the shear stiffness of deck form systems used in the bridge industry. The conventional eccentric connection of bridge metal deck forms reduces their shear stiffness dramatically. However, recent studies have shown that a simple modification to the connection detail can significantly increase the shear stiffness of bridge metal deck form panels. To the best of the author's knowledge currently there is not a design aid that can be used by bridge engineers to estimate the stiffness of bridge metal deck forms. Therefore, bridge engineers rely on previous test results to predict the stiffness of bridge metal deck forms in bracing applications. In an effort to provide a design aid for bridge design engineers to rely on bridge metal deck forms as a bracing source during construction, cantilever shear frame test results of bridge metal deck forms with and without edge stiffened panels have been compared with the SDI Diaphragm Design Manual and ECCS Diaphragm Stressed Skin Design Manual stiffness expressions used for building industry deck forms. The bridge metal deck form systems utilized in the tests consisted of sheets with thicknesses of 0.75 mm to 1.90 mm, heights of 50 mm to 75 mm and lengths of up to 2.7 m; which are representative of bridge metal deck forms frequently employed in steel bridge constructions. The results indicate that expressions provided in these manuals to predict the shear stiffness of building metal deck form panels can be used to estimate the shear stiffness of bridge metal deck form bracing systems with certain limitations. The SDI Diaphragm Design Manual expressions result in reasonable estimates for sheet thicknesses of 0.75 mm, 0.91 mm, and 1.21 mm and underestimate the shear stiffness of 1.52 and 1.90 mm thick bridge metal deck forms. Whereas, the ECCS Diaphragm Stressed Skin Design Manual expressions significantly underestimate the shear stiffness of bridge metal deck form systems for above mentioned deck thicknesses.

지반앵커로 지지된 강성 지하연속벽체의 상세계측 결과분석 및 역해석 평가 (Analysis of Monitoring Results and Back Analysis for Rigid Diaphragm Wall Supported by Ground Anchor)

  • 이종성;황의석;조성환;이준환
    • 한국지반공학회논문집
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    • 제25권5호
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    • pp.39-46
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    • 2009
  • 본 연구에서는 조립질의 퇴적층이 깊게 분포되어 있고 지하연속벽과 지반앵커로 구성된 굴착현장을 선정하여 흙막이 벽계와 배면지반의 수평변위 비교, 벽체 내부에 깊이별로 설치된 토압계와 앵커 두부에 설치된 축력계로 부터의 토압과 축력의 변화등을 정밀하게 평가분석 하였다. 분석결과 강성벽계의 수평변위는 벽체 내부에 설치된 지중경사계로 측정된 결과가 보다 합리적인 것을 알 수 있었다. 그리고 단계별 굴착에 따른 토압의 변화를 분석한 결과, 굴착이 진행됨에 따라 지반앵커의 선행 긴장력으로 인해 배면 토압은 점차 증가하는 경향을 나타내고 있었으며, 지하연속벽이 강성 벽체지만 퇴적층이 깊고 굴착 깊이가 깊은 경우에는 연성벽체에서 경험적으로 평가된 경험토압과 유사한 결과가 나타남을 확인하였다.

정밀 로봇용 하모닉 드라이브의 실크 햇 형상에 따른 구조해석 (Structural Analysis for Silk Hat type of the Harmonic Drive for Precision Robot)

  • 남원기;함성훈;오세훈
    • 동력기계공학회지
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    • 제15권5호
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    • pp.61-66
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    • 2011
  • Recently, the speed reducer which is applied to robot has conducted a steady development on developments in the field of robotics. Among them, Harmonic drive is a high-stiffness, precision-controlled speed reducer and has high precision, compact, light in weight and high-reduction-ratio characteristics. The feature of flexspline of Harmonic Drive are two types. One is Cup type, the other is Silk Hat type. Silk Hat type is used in case of lighter and more compact in spatial because Silk Hat Type is hollow. According to the shape of silk hat, diaphragm is fractured because stress is concentrated. In this paper, the various shapes of silk hat are suggested to improve the durability of silk hat. And in the case of each shape, a study on stress and deformation using the FEM tool was carried out on flexspline.

2거더 강-콘크리트 합성형 철도교의 거동에 대한 2차부재의 영향 평가 (The Effect of Secondary Members on the Behavior of Steel-Concrete Composite Two-Girder Railway Bridges)

  • 배두병;조준희
    • 한국철도학회논문집
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    • 제8권1호
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    • pp.41-50
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    • 2005
  • Steel -Concrete Composite two girder railway bridges applying high performance steel with extra thick plate have economic and aesthetic advantages due to the simplification of manufacturing and construction process. However, steel bridges are seldom adopted in domestic railway bridge, since steel bridges are not efficient as R.C bridges considering dynamic characteristics and noise, etc. While highway bridges do not have lower horizontal bracing and larger interval of diaphragm cross beam, railway bridges install lower horizontal bracings to control the torsion due to heavy eccentrical line load. Accurate finite element analysis were performed with the parameters of existence of bracing and bracing shape, with the cross beam interval and stiffness, etc. To find out the effects of secondary members such as horizontal bracings and diaphragms, static md dynamic analysis have been performed by using finite element method. In this study, few member plate-girder bridges are analyzed with variable span lengths to examine the dynamic behavior and limits of damping. And though lateral bracings are members against torsion, but lateral bracing's absence is no big problem. Time history analysis using mode superposition method makes proof of this result.

한우 송아지의 반전성열체 (Schistosomus reflexus in Korean native calf)

  • 김종섭;허찬권;이종환;이종한
    • 대한수의학회지
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    • 제36권2호
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    • pp.289-296
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    • 1996
  • A case of schistosomus reflexes in Korean native female calf was observed macroscopically and radiographically. The results were summarized as follows. 1. The abdominal visceral organs were exposed. 2. The vertebral column bent laterally to the left, and the sacrum approached to the cranium by reflected caudal lumber vertebrae, presenting S-shaped lateral twisting of the vertebrae. 3. The right ribs reflected laterally and dorso-cranially from the 7th rib to 13th rib. The left ribs bent caudally from 8th rib to 13th rib. 4. The length of rudimentary 6th right rib was one half of normal size and the 7th right rib was one third. 5. The sternum was bifid split from the fourth sternebra through the xyphoid cartilage. 6. The diaphragm was intact and thoracic cavity was reduced in size. The lung and heart severely deformed in shape and size. 7. The liver markedly deformed in shape and thickness. 8. The pelvic cavity was reduced in size by compression laterally to the left. 9. The uterus horn, ovary, urinary bladder, and urethra were severely deformed in the shape and position.

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Morgagni 탈장증 수술 1예 (Surgical Treatment of the Morgagni Hernia: report of one case)

  • 김송명
    • Journal of Chest Surgery
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    • 제12권4호
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    • pp.429-433
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    • 1979
  • Morgagni hernia is a rare condition of the congenital diaphragmatic hernia which Is located at the anteromedial portion of the diaphragm, and is located immediately posterior to the sternum. Its cause is considered by embryologic defect and the abdominal organs are passed through a defect. The incidence is predirected women over 50 years old. Its synonym is hernia of subcostosternal, retrosternal, parasternal, rectocostoxiphoid, anterior diaphragmatic or Larrey`s. This report presents a symptomatic Morgagni hernia of ten months old male child on whom the diagnosis was established and was operated at the Busan Gospel Hospital. This patient was admitted with the chief complaints of mild cyanosis, frequent upper respiratory infections and protrusion of the right lower anterior chest. Herniorrhaphy was performed through the upper abdominal midline incision, hernial contents of the omentum and the colon, and sac as noticed from the Larrey`s space measuring 4 x 2 cm. in diameter and oval in shape. Interrupted sutures without difficulty repaired the defect. The cyanosis was disappeared and the patient had uneventful course of post-operative period. The patient was discharged at 7th. postoperative day. This case presentation with a brief review of literatures is given.

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이형 하부다이아프램으로 보강된 각형 CFT 기둥-보 접합부의 내진성능에 관한 연구 (A Study on Seismic Performance for CFT Square Column-to-Beam Connections Reinforced with Asymmetric Lower Diaphragms)

  • 최성모;윤여상;김요숙;김진호
    • 한국강구조학회 논문집
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    • 제15권5호통권66호
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    • pp.579-589
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    • 2003
  • 콘크리트충전 강판(CFT)기둥과 H-형강 보 접합부의 기존 보강 방식은 상 하 동일 다이아프램 형태로 처리하는 것이 일반적이지만, 우리나라와 같은 중 약진지역에서는 하부플랜지에 인장 발생률이 적으므로 하부측을 단순화시켜 경제적인 접합부를 만들 수 있다. 우선적으로 본 논문에서는 단순인장실험을 실시하여 인장거동을 파악하고, 그 결과를 확장 적용하여 하부측 단순화의 타당성을 검증하였다. 본 실험에서는 상부에 복합십자형 다이아프램(Combined Diaphragm)을 하부에는 네 가지 형식 즉, 복합십자형, 무보강, 수평 T-bar, 수직 Plate를 다아아프램으로 제작한 실대크기의 실험체를 ANSI/AISC SSPEC-2002 가력 프로그램(AISC,2002)에 따라 반복가력실험을 하였다. 하부다이아프램에 사용된 수평 T-bar와 수직 Flat bar의 스터드 볼트는 횡력에 의해 하부다이아프램에 인장력이 가해질 때 보 플랜지의 인장력을 내부 콘크리트에 전달하기 위함이다. 각각의 실험체는 하부 인장시 내력의 차이가 조금 있었으나 모든 실험체가 AISC에서 규정하고 있는 합성보통모멘트 골조인(AISC,2002) 0.01rad의 비탄성회전 능력을 발휘하였다. 하부 접합부의 거동을 분석한 결과, 단순화된 하부다이아프램은 내력과 강성뿐만 아니라 소성 변형 능력이 우수하며 현장에 사용하기에 충분한 내진성능을 나타냄을 입증하였다.

지그비 통신 기반의 근거리 무선 호흡모니터 시스템 (Zigbee Based Wireless Respiration Monitor System)

  • 이인광;김성식;장종찬;김군진;김경아;이태수;차은종
    • 전기학회논문지
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    • 제57권1호
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    • pp.142-147
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    • 2008
  • Abdominal circumference changes due to breathing by the respiratory muscle activity such as diaphragm, which would partially represent the lung volume variation. The present study introduced conductive rubber molded in a cord shape incorporated with a patient's pants. The conductive rubber cord operated as a displacement transducer to measure the lung or abdominal volume changes. Signal extraction circuitry was developed to obtain the volume and its derivative(or the flow) signals followed by wireless transmission based on the Zigbee communication protocol in a size of $65mm{\times}105mm$ easily put in pocket. Breathing frequency was accurately evaluated and breath pattern analysis seemed feasible, since respiratory behaviours such as maximal inspiration and cough were well identified. Remote wireless receiver module also enabled to monitor both volume and flow signals during resting breathing on a PC terminal.

Surgical Removal of the Lung Lobe Metal Foreign Body in a Dog

  • Hwang, Yawon;Kang, Jihoun;Chang, Dongwoo;Kim, Gonhyung
    • 한국임상수의학회지
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    • 제34권2호
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    • pp.108-111
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    • 2017
  • A 4-year-old, weighing 7.6 kg, castrated male, Pug presented with ingestion of gastric cavity foreign body. Physical examination revealed panting, retching and hyper-salivation. Blood chemistry and complete blood cell count were normal, but hypophosphatemia was observed. An abdominal radiograph revealed the foreign body (FB), round shape and 2 cm length, at the pyloric region of stomach. A thoracic radiograph revealed an incidental metal FB, 3.5 cm length, at the cranial portion of the diaphragm. An upper gastrointestinal endoscopy was performed to remove the FB in the stomach and then a peach-pit was removed. However the metal FB was not found in the esophagus therefore a lateral thoracotomy was performed. A right lateral thoracotomy through the $7^{th}$ intercostal space was accomplished to expose the right caudal lung lobe. After open the thoracic cavity, foreign body was not observed by gross evaluation and caudal lung lobe was attached to the diaphragm. The FB was identified inside the lung lobe and surrounded by granulation tissue. The metal FB (sewing needle) was removed with blunt dissection and incised lung lobe was sutured using absorbable suture material PDS 4-0 with interrupted suture. A thoracotomy tube was inserted into the thoracic cavity during surgery. Patient's respiration became stable after surgery. A chest tube was removed 3 days after surgery. No complications were noted and the dog was discharged 4 days after surgery. In small animal, foreign body ingestion is a common reason for emergency. After ingestion of the FB, perforation through the esophagus and migration to inside the lung lobe is not common in small animals. In this case, thoracic metal FB was identified incidentally and removal of a thoracic FB with thoracotomy was performed successfully.

대곡면 후곡판 성형을 위한 블랭크 지지구조의 적합성 연구 (A Compatibility Study on Blank Support Structure for Large and Curved Thick Plate Forming)

  • 임미래;곽봉석;강범수;구태완
    • 소성∙가공
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    • 제28권6호
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    • pp.335-346
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    • 2019
  • Thick plate forming is presented to manufacture a large and curved member of steam turbine diaphragm. Due to three-dimensional asymmetry of target geometry, it is hard to consistently keep the blank position in die cavity between forming punch and die. In order to relieve the position instability of the blank during the thick plate forming, a blank support structure is proposed to be composed of guide pins and linear bearing, and blank guide arm enlarged from both longitudinal ends of the thick blank. In this study, parametric investigations with regard to the geometric position and width of the blank guide arm are carried out. As main geometric parameters, 2 positions such as maximum curvature region and minimum one on a curved cross-section profile of the target shape are selected, and 14 widths of the blank guide arm are considered. Using 28 variable combinations, three-dimensional numerical simulations are performed to predict the appropriate range of the process parameters. The compatibility and validity of the blank support structure with the blank guide arm for the thick plate forming is verified through the thick plate forming experiments.