• 제목/요약/키워드: big bracket

검색결과 13건 처리시간 0.027초

외부강선 보강을 위한 압축형 단부 브라켓의 개발 연구 (A Study on Development of Compressive End-Bracket for External Prestressing Method)

  • 한만엽;정문연
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.697-700
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    • 1999
  • Strengthening existing structure using the exterior steel wire is utilized because of their high adaptability and strengthening efficiency. In the practical aspect, the fixing methods, which are generally adopted have caused problems. A new method is not easily designed because of the weak points, a limit of tension stress, and complex transmit processes. To make up for the weak points in the current fixing method, tensile end bracket similar to a supporting plate has been developed, but the tensile end bracket was relatively big because of increasing length welded between the end plate and the resisting plate.

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기존선 가동브래킷 곡선 당김 금구의 완충기능 필요성 (A Need of Buffering Function for Full-Off Fitting on Movable Bracket using Conventional Line)

  • 안영훈;김철수;이승일
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.219-222
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    • 2007
  • The Full-Off Fitting of Movable Bracket using conventional line have received a dynamic contact impact between contact wire and pantograph of electric rolling stock, so this impact cause a rapid vibration of foreword and back near the supporting point of movable bracket. The Full-Off Fitting on Movable Bracket in conventional line differs from that in high speed line. Now conventional line have required a speed up for new electric locomotive and electric car. In speed-up track and big impact place, the Full-Off Fitting and the dropper often get demage. We have done a study of buffering function to solve that problem in conventional line. We have find a need adopting buffer fitting. It is decrease a dynamic impact between contact wire and pantograph of electric rolling stock.

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유조선 화물창내 대형 브라켓 치수 최적화 연구 (A Study on Size Optimization of the Big Bracket in the Cargo Hold of Crude Oil Tanker)

  • 신상훈;이종환;김도현;권진칠
    • 대한조선학회 특별논문집
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    • 대한조선학회 2005년도 특별논문집
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    • pp.63-68
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    • 2005
  • Optimum design of the big brackets is performed through iterated 3-D FE analyses to meet the permissible limits of stress, which consumes an excessive amount of calculation time. Therefore, this study has been prepared to determine rapidly and accurately an optimum size and scantling of the big brackets at the initial design stage. The generalized slope deflection method (GSDM) based on the span point concept is applied to enhance the efficiency of iterated structural analyses. The accuracy and applicability of the present method is verified by comparing with a detail 3-D FE analysis of web frame structures. As an optimization technique, evolution strategies (ES) are applied using discrete design variables for practical design.

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재생 브라켓의 전단접착강도에 관한 비교 연구 (A COMPARATIVE STUDY OF BOND STRENGTH OF RECYCLED BRACKETS)

  • 서정훈;최은아
    • 대한치과교정학회지
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    • 제28권4호
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    • pp.641-657
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    • 1998
  • 본 연구는 열을 이용한 금속 브라켓의 재생 처리시, 기저부 형태와 브라켓 재생 방법에 따른 전단접착강도 및 브라켓 탈락 양상을 비교하고자 시행되었다. 교정 치료를 위해 발거된 건전한 소구치 252개를 수집하고, Type I, Type II, Type III 스탠다드 브라켓을 각각 재생 방법에 따라 네 군으로 나누어 준비된 소구치에 접착하고, Instron Universal Testing Machine(Model 4466)으로 전단접착강도를 측정하였으며, 브라켓의 탈락 양상을 관찰하고 브라켓 기저부의 주사전자현미경 소견을 관찰하였다. SPSS 통계처 리 프로그램을 이용하여 일원분산분석(oneway ANOVA), Scheffe's multiple range test를 실시하여 다음과 같은 결론을 얻었다. 1. 브라켓 기저부 형태에 따른 전단접착강도는 유의차가 있었으며(p<0.001), 그 크기는 Type III(round indentation, micro-etched base), Typ I(foil-mesh base), Type II(grooved integral base, micro-etched)의 순이었다. 2. 생 방법에 따른 전단접착강도는, Type I, Tpe II 브라켓에서는 Big Jane에 1분간 처리시 우수한 결과를 보였고 (p<0.05), Type III 브라켓에서는 각 군간 유의한 차이를 보이지 않았다(p>0.05). 3. Type I, Type II 브라켓은 기저부-레진 계면에서 가장 높은 빈도로 탈락하였고, Type III 브라켓에서는 레진의 절반 가량이 치면에 잔존하는 탈락 양상이 가장 많았다. 4. 탈락 양상에 따라 탈락시의 전단접착강도가 유의성 있는 차이를 보였는데(p<0.05),브라켓 탈락시 접착제의 절반 가량이 치면에 잔존하는 경우 전단접착강도가 가장 큰 것으로 나타났다. 5. 브라켓 재생 후 기저부에 남아 있는 접착제는 전단접착강도의 감소에 영향을 미치지 않았다.

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승용차 시트프레임의 강도해석 (The Strength Analysis of Passenger Car Seat Frame)

  • 임종명;장인식
    • 한국자동차공학회논문집
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    • 제11권6호
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    • pp.205-212
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    • 2003
  • This paper may provide a basic design data for the safer car seat mechanism and the quality of the material used by finding out the passenger's dynamic behavior when protected by seat belt during collision. A computer simulation with finite element method is used to accomplish this objective. At first, a detailed geometric model of the seat is constructed using CAD program. The formation of a finite element from a geometric data of the seat is carried out using Hyper-Mesh that is the commercial software for mesh generation and post processing. In addition to seat modeling, the finite element model of seat belt and dummy is formed using the same software. Rear impact analysis is accomplished using Pam-Crash with crash pulse. The part of the recliner and right frame is under big stress in rear crash analysis because the acceleration force is exerted on the back of the seat by dummy. The stress condition of the part of the bracket is checked as well because it is considered as an important variable on the seat design. Front impact model which including dummy and seal belt is analyzed. A Part of anchor buckle of seat frame has high stress distribution because of retraction force due to forward motion of dummy at the moment of collision. On the basis of the analysis result, remodeling and reanalysis works had been repeatedly done until a satisfactory result is obtained.

60m Beam VLCC Fore/Aft Cargo Hold에 대한 구조 안정성 및 피로강도 평가 (Structural Strength and Fatigue Strength Assessment for Fore/Aft Cargo Hold of 60m Beam VLCC)

  • 이상우;최지훈;김명섭;김만수;이영만;김광석
    • 대한조선학회 특별논문집
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    • 대한조선학회 2005년도 특별논문집
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    • pp.84-89
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    • 2005
  • The double hull VLCC(Very Large Crude Oil Tanker) have been designed to have each four(4) longitudinal bulkheads and transverse bulkheads in general. Actually, the inside longitudinal bulkheads among four(4) longitudinal bulkheads, which are extended up to the end of the aft cargo hold for continuity of the members, have been designed with knuckled type inboard due to the narrowed hull shape at bottom region, but sometimes the straight type of longitudinal bulkheads were adopted based on the degree of the hull lines shape. However, regardless the type of longitudinal bulkheads, inside and outside longitudinal bulkheads conflict each other in aft cargo hold region This makes the structure more complex thus giving difficulties to structural design and production. Recently, a vessel of straight type was reported to have cracks on bracket end and tripping bracket toe in aft cargo hold region. As a solution to this problem, in designing the first 60m Beam VLCC, DSME developed a new cargo hold structure which is good in production and structural point of view by structural strength and fatigue analysis of fore and aft cargo hold.

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콘크리트 교량의 외부강선 보강을 위한 앵커키 정착장치의 개발 연구 (Development of the Bracket for External Prestressing Method for Slab Bridge)

  • 한만엽;이상열
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.1009-1014
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    • 2001
  • This study is to develop the end anchorage of external steel reinforcement of RC slab bridges. External prestress method using the existing steel is that When the anchorage is installed in slab end, a plenty of anchor bolts were required because the only tangential stress of anchor bolt received a tendon force. Then, for this reason, the wide end anchorage was required and the shape was complicate. But this reinforcement method using method that inserts anchor key at concrete surface cut a groove gets big internal force comparing to the anchorage using existing anchor bolt. Furthermore, the number of anchor bolt for installing apparently will be reduced, and the operation will be convenient because a small anchorage of a simple shape will be received a great tendon force.

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티어심 파손 강도를 고려한 동승석 에어백 도어시스템의 최적 설계 (Optimal Design of Passenger Airbag Door System Considering the Tearseam Failure Strength)

  • 최환영;공병석;박동규
    • 자동차안전학회지
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    • 제13권3호
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    • pp.60-68
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    • 2021
  • Invisible passenger airbag door system of hard panel types must be designed with a weakened area such that the side airbag will deploy through the instrument panel as like intended manner, with no flying debris at any required operating temperature. At the same time, there must be no cracking or sharp edges in the head impact test. If the advanced airbag with the big difference between high and low deployment pressure ranges are applied to hard panel types of invisible passenger airbag (IPAB) door system, it becomes more difficult to optimize the tearseam strength for satisfying deployment and head impact performance simultaneously. It was introduced the 'Operating Window' idea from quality engineering to design the hard panel types of IPAB door system applied to the advanced airbag for optimal deployment and head impact performance. Zigzab airbag folding and 'n' type PAB mounting bracket were selected.

액티브 시니어 남성(55~69세) 체형 분석 -중년 남성(35~54세)과 체형 비교를 중심으로- (A Study on Analysis of Body Types of Active Senior Males (aged 55-69) -Focused on the Comparison with the Middle Aged Males (aged 35-54)-)

  • 김지은;김은경
    • 한국의류학회지
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    • 제41권4호
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    • pp.722-740
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    • 2017
  • This study was conducted to offer basic data that can be used in a clothing industry for active senior males that are emerging as a new consumer bracket in a rapid aging age. To this end, this study conducted an analysis of 'younger' older male body types based on data from the 6th Size Korea. As a result of the body type analysis of 'younger' older males who are considered active seniors in comparison to 'middle' aged males, the former's height items became shorter compared to 'middle' aged males, but circumference items were bigger. Males aged 35-69, who are 'middle' aged males and 'younger' old males were divided into three body types in this study: Type1- small body type with protruded belly, compared to weight. Type 2- body type of slim torso with wide shoulder-back widths. Type3- big body type overall with tall height and heavy weight. According to body type distribution by age group, the middle-aged males had Type2 body type the most. The younger-old males showed type1 the most. There is a need to reflect the body types of active senior male characteristics in apparel pattern design because the current fits are not appropriate if active senior males wear clothing targeted for males aged 30-50.

AUTOMATIC CABBAGE FEEDING, PILING, AND UNLOADING SYSTEM FOR TRACTOR IMPLEMENTED CHINESE CABBAGE HARVESTER

  • Song, K.S.;Hwang, H.;Hong, J.T.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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    • pp.489-497
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    • 2000
  • Since Chinese cabbages weigh 3 to 5kgf and are big in size at the time of harvest, handling operations such as harvesting, loading and unloading including transportation require the highest labor demand among all other cultivation processes. Recently, though several cabbage harvesters were developed in Japan and Europe, those harvesters were not suitable for Chinese cabbages cultivated in Korea because of the size and shape. The cabbage harvester is almost meaningless without any proper cabbage piling and pallet unloading mechanism. Most harvesters developed so far adopted a sort of slide and free falling way in collecting cabbages into the pallet. Three or four labors are usually required for cleaning incoming cabbages and loading those in the pallet. Because of the required time for piling cabbages without severe damage and the required space capacity to carry empty and loaded pallets, harvesting speed should be adjusted in accordance with time required for consecutive operations. Up to now, any automatic or semi-automatic collecting device has not been developed in the world to pile cabbages on the layer one by one into the pallet in the ordered way with little damage and to unload pallet from the harvester continuously during the harvest process. To compromise system expenses and function, Semi-automatic cabbage piling and pallet unloading mechanism was devised and it required one labor. The foldable mesh pallet with a size of 1050mm x 1050mm x 1000mm and holding capacity of around 70 cabbages was utilized. The prototype for piling and unloading mechanism was composed of three parts such as feeding device, automatic piling device with retractable bellows, and pallet unloading device. Prior to developing the prototype, the geometric properties and the amount of the damage of the cabbage caused during the piling operation were investigated. Considering the height of the pallet, a series of cabbage carrying plates were mounted to the bracket chain to lift and to carry cabbages to the loading device. Indoor laboratory experiments showed that the cabbage carrying chain conveyor worked successfully. Considering the conveying speed 0.46m/sec of the pull up belt from the cabbages on the ground, the speed of cabbage carrying chain conveyor worked property in the range of 0.26m/sec to 0.36m/sec. The system allowed the operator to modify the position of cabbage slightly. Overall system worked successfully resulting into almost same capacity without severe damage to the cabbage as human did.

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