• 제목/요약/키워드: Cause of deformation

검색결과 483건 처리시간 0.028초

주조 프레임을 강 구조물로의 대체에 관한 연구 (A Study on Substitution of Steel structure for Casting Frame)

  • 홍민성
    • 한국생산제조학회지
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    • 제8권1호
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    • pp.142-149
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    • 1999
  • A machine frame has been manufactured by casting. However, due to the development of the industrial society, 3-D duties was refused. Especially, the declination of the casting industry makes it difficult to produce the frame. Many companies still manufacture the small casting products. The large casting products are extremely limited and manufactured for their own use. Therefore, it is difficult to keep the term of order. In this study, the characteristics of steel structure which is produced by welding were identified in the view of mechanical strength of steel structure which is produced by welding were identified in the view of mechanical strength to substitute steel structure for casting frame. But welding structure has the residual stress, HAZ and welding deformation. Residual stress and HAZ especially cause crack growth. The proposed steel structure, based on the simulation and experiment(tensile curve and S-N curve), can reduce not only the producting term but also the weight of the frame.

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콘크리트 보강용 하이브리드 FRP 리바의 특성 (The properties of hybrid FRP rebar for concrete structures)

  • 원종필;박찬기;황금식;윤종환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.255-260
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    • 2003
  • The corrosion of steel rebars has been the major cause of the reinforced concrete deterioration. It is FRP rebar that is developed to solve problem of such steel rebar. FRP rebar in concrete structures should be used as a substitute of steel rebars for that cases in which aggressive environment produce high steel corrosion, or lightweight is an important design factor, or transportation cost increase significantly with the weight of the materials. But FRP rebar have only linearly elastic behavior; whereas, steel rebar has linear elastic behavior up to the yield point followed by large plastic deformation and strain hardening. Thus, the current FRP rebars are not suitable concrete reinforcement where a large amount of plastic deformation prior to collapse in required. The main objective of this study was to develop new type of hybrid FRP rebar. The manufacture of the hybrid FRP rebar was achieved pultrusion, braiding and filament winding techniques. Tensile and interlaminar shear test results of hybrid FRP rebar can provide its excellent tensile strength-strain behavior and interlaminar stress-strain behavior.

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쉐도우마스크의 열변형과 전자빔의 오차 해석 (Analysis of Thermal Deformations of Shadow Mask and Electronic Beam Mislanding)

  • 김현규;박영호;김상기;임세영
    • 전자공학회논문지B
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    • 제31B권6호
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    • pp.81-90
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    • 1994
  • Finite element analysis is performed for transient thermal deformation of a shadow mask inside the Braun tube and the landing shift or mislanding of the electronic beam is calclated. The shadow mask has numerous slits through which the electronic beams are guided to land on the designed phosphor. Its thermal deformations therefore cause the mislanding of the electronic beam and result in decolorization of a screen. For realistic finite element analysis, firstly the effective thermal conductivity and the effective elastric modulus are calculated, and the shadow mask is modeled as shell without slits. Next the nonlinear finite element formulation is developed for transient heat transfer on the shadow mask, wherein thermal radiation is a major heat transfer mechanism. Analysis of the resulting thermoelastic deformations is followed, from which the mislanding of the electronic beam is obtained. The present finite element scheme may be efficiently used for thermal deformation design of a shadow mask.

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필릿용접에서 리브높이에 따른 용접변형 해석에 대한 연구 (A Study on the Welding Distortion Analysis According to Rib Height in Fillet Welding)

  • 김용래;송규영;왕초;김재웅
    • Journal of Welding and Joining
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    • 제31권6호
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    • pp.107-111
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    • 2013
  • The welding distortion is caused by welding heat in the structures which are widely used in shipbuilding and automotive industries, thus many researchers have proposed such methods to control the welding distortion through trials and numerical studies. The welding distortion has been the main cause of low productivity due to the structural strength degradation, apparent flaw, additional deformation caused by the process followed the current assembly step, and the increase of correction workload. The deformation of fillet welding is investigated in this study, and the influence of the rib height on the welding distortion is verified through the actual experiment. And the numerical analysis model using the FE software MSC.marc for analysis of welding distortion is proposed.

Multimodality and Non-rigid Registration of MRI' Brain Image

  • Li, Binglu;Kim, YoungSeop
    • 반도체디스플레이기술학회지
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    • 제18권1호
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    • pp.102-104
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    • 2019
  • Registering different kinds of clinical images widely used in diagnostic and surgery planning. However, cause of tumor growth or effected by gravity, human tissue has plenty of non-rigid deformation with clinically. Non-rigid registration allows the mapping of straight lines to curves. Therefore, such local deformation makes registration more complicated. In this work, we mainly introduce intra-subject, inter-modality registration. This paper mainly studies the nonlinear registration method of 2D medical image registration. The general medical image registration algorithm requires manual intervention, and cost long registration time. In our work to reduce the registration time in rough registration step, the barycenter and the direction of main axis of the image is calculated, which reduces the calculation amount compared with the method of using mutual information.

양문여닫이 냉장고에서 도아의 단차영향 연구 (A Study on the Door Height Difference of the SBS Refrigerator)

  • 신광철;채수원
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.528-533
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    • 2004
  • This paper deals with the issue of door height difference (DHD) which occurs for SBS refrigerator necessarily. In order to identify the cause of DHD, analysis of refrigerator structure and entire process from door manufacturing to usage have been investigated. From diverse experiments, it was found that the flatness of the floor was a main causing factor. In order to decrease the DHD , the effects of 6 design parameters to control of cabinet deformation have been investigated by using DOE(design of experiment) and finite element analysis. Based on the correlation equation, it was possible to estimate the DHD for new refrigerator design.

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쉐도우마스크의 열변형 해석 -온도분포 (Thermal Deformation Analysis of Shadow Mask : Temperature Distribution)

  • 김현규;천현태;임세영
    • 대한기계학회논문집
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    • 제17권10호
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    • pp.2574-2581
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    • 1993
  • A Shadow mask in C. R. T. (Cathod Ray Tube) undergoes a temperature increase due to impinging electron beams emitted from guns, and thermal deformation from such temperature rise may cause the electron beams to island on the panel, and thus give rise to depolarization. Hence the analysis of temperature distribution for a shadow mask is an important procedure for designing the shadow mask. In this paper, we are concerned with nonlinear finite element analysis of the temperature distribution on a shadow mask. First of all, we replace shadow mask, containing numerous apertures of a slit type, by an orthotropic shell without apertures, and calculate the apparent thermal conductivities. Because of thermal radiation, which is one of the major heat transfer mechanism for shadow masks, the resulting finite element equation is nonlinear and solved by the Newton method. Finally numerical examples are illustrated for a 21" FST(Full Square Tube) shadow mask, and followed by discussion.sion.

전륜 Insulator 이음 개선을 위한 강건 구조 방안 연구 (A Study On The Robust Structure For Improvement of Front Insulator Noise Improvement)

  • 이상종
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제17권3호
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    • pp.197-206
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    • 2017
  • Purpose: Clarify the cause of the noise by the front wheel strut insulator, which is located in close proximity to the driver's seat. Methods: The improvement mechanism was confirmed through failure analysis and reproduction test of the joint generation mechanism. In addition, the main factors were analyzed through principal test. Results: This paper describes the mechanism of occurrence of noise due to deterioration and hardness increase of rubber, deformation on severe road surface, foreign matter and water inflow in cold weather. Conclusion: We found that the insulator and body deformation can be minimized without increasing the thickness of the body and the insulator and reinforcing the body by dispersing the input load by applying load distribution structure instead of the local forming structure of the insulator in the insulator robust structure.

TiAl 금속간 화합물의 미세조직에 따른 고온변형특성 (High Temperature Deformation Behavior of Ti-Al Intermetallic Compound - Microstructure Effect)

  • 하태권;정재영;이광석;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 춘계학술대회논문집
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    • pp.295-298
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    • 2003
  • High temperature deformation behavior of a Ti-Al intermetallic compound has been investigated. Specimens with a near gamma and a lamella structures were obtained by performing heat treatment at 1200 and 1330$^{\circ}C$, respectively, for 24 hr and stabilized at 900$^{\circ}C$ for 4 hr followed by air cooling. A series of load relaxation tests has been conducted on these samples at temperatures ranging from 850 to 950$^{\circ}C$ to construct flow curves in the strain rate range from 10$\^$-6//s to 10$\^$-3//s. Strain hardening was observed even at the temperature of 950$^{\circ}C$ in both the near gamma and the lamella structures. Further aging treatment for 12 hr at test temperatures has found to cause no softening in both microstructures.

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반강성포장에 대한 실험적 연구 (An Experimental Study on Semi-Rigid Pavement)

  • 임승욱;양성철;윤경구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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    • pp.225-231
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    • 1996
  • The dense graded asphalt concrete materials have been used for construction of pavement for a long time. The performance of asphalt concrete pavement, however, is influenced by various factors including high temperature and heavy axle loads which cause plastic deformation. The plastic deformation is one of the main functional disadvantages of flexble pavement. In this study, the semi-rigid pavement is considered to solve the problem. A set of experimental evaluation on semi-rigid pavement material has been coducted in laboratory to obtain it's physical properties and serviceabilities. The results of tests, including compressive strength, flexural strength, ravelling and wheel tracking, show that the semi-rigid pavement has a good mechanical properties and serviceabilities. Consequently, the semi-rigid pavement may be suitable to bridge deck, tunnel, slow lane and parking area pavements.

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