• 제목/요약/키워드: thin plate

검색결과 1,173건 처리시간 0.031초

평판 인텐시티 측정을 통한 근접장 음향 인텐시티와 손실 계수 측정법 (Measurement of Near Field Sound Intensity and Loss Factor Using Plate Intensity Measurement)

  • 김용조;김양한
    • 소음진동
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    • 제7권4호
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    • pp.589-596
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    • 1997
  • A energy equation for a thin plate and surrounding fluid is derived. The equation essentially determines the relation between internal loss of thin plate, energy of acoustic radiation, and structure intensity. We attempted to use this relation to measure internal loss of thin plate. The significance of this approach is that internal loss at any point of a thin plate can be measured. The quality of this measure is dicated by the accuracy of associated measurement systems such as structure and acoustic intensity measurements. A strain gauge bridge system has been developed to measure structure intensity of thin plate. Its performance is tested by experiments.

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레오로지 박판의 전자교반을 응용한 진공 저압주조 제조공정 (Fabrication Process of Rheology Material Thin Plate Using Vacuum Low Pressure Die-casting Process with Electromagnetic Stirring)

  • 장신규;배정운;진철규;강충길
    • 한국주조공학회지
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    • 제32권1호
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    • pp.16-23
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    • 2012
  • In this study, we develop the lower pressure die casting with rheo-forming process of A356 aluminum alloy and vacuum system which can control the crystal size and obtain the high strengthened-light material. Using this process, we fabricate the thin plate for bipolar plate through the low pressure die casting with electromagnetic stirring and vacuum-evacuation which can control the crystal grain by electromagnetic stirring. Thin plate ($110mm{\times}130mm{\times}1mm$) is fabricated by this process. The average Vickers hardness of thin plate is about 77 HV.

등가하중법을 이용한 PCTC 박판 블록 용접변형에 관한 연구 (A Study on Welding Deformation of Thin Plate Block of PCTC by Using Equivalent Load Method)

  • 강성구;양종수;김호경;허주호
    • 대한조선학회 특별논문집
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    • 대한조선학회 2011년도 특별논문집
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    • pp.106-111
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    • 2011
  • The use of thin plate increases due to the need for light weight in large ship. Thin plate is easily distorted and has residual stress by welding heat. Therefore, the thin plates should be carefully joined to minimize the welding deformation. In this study, the welding deformation of PCTC which use a thin plate is investigated by using equivalent load method. The analysis model of 10, 11, 12, upper and garage deck is composed of thin plate of 6mm which is susceptible to welding heat. For two different welding sequences, the welding deformation is calculated and its trend is investigated. The influence of gravity on welding deformation is studied.

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박판이 부착된 사각노즐에서 분사되는 Sweeping jet의 유동 및 열전달 특성 (Heat transfer and flow characteristics of sweeping jet issued from rectangular nozzle with thin plate)

  • 김동욱;정재훈;서현덕;김현동;김경천
    • 한국가시화정보학회지
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    • 제17권2호
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    • pp.58-66
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    • 2019
  • This study investigated heat transfer and flow characteristics of a sweeping jet issued from a rectangular nozzle with a thin plate. A thin vertical aluminum plate was attached on outlet of fluidic oscillator to increase velocity of central area with Coanda effect and enhance heat transfer performance. From visualization and PIV experiments, sweeping jet with a thin plate has larger velocity distribution in center region than that of the normal sweeping jet while oscillating frequency is similar as the normal one. Thermographic phosphor thermometry method was used to visualize the temperature field and Nu distribution of plate with impinging sweeping jet with thin plate. Four Reynolds numbers and three jet-to-wall distances were selected as parameters. It is found that heat transfer performance in the low jet-to-wall spacing was enhanced as the cooled area was expanded. However, when the jet-to-wall spacing became greater than 8dh, heat transfer performance became similar due to reduced impinging velocity.

박판 필릿용접시 변형제어를 위한 장력법 적용 (Application of Tensioning Method to Deformation Control of Thin Plate Fillet Weld)

  • 이주성;박재우
    • 한국해양공학회지
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    • 제22권1호
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    • pp.64-69
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    • 2008
  • As it has been well appreciated from the viewpoint of efficiency, The weld-induced deformation control is one of the most important issues in marine structure production. In the case of thin plate block, weld-induced deformation is more serious than in the case of relatively thick plate block. The heat affect zone of thin plates is wider than that of thick plates with the same heat input. Among weld-induced deformations, the buckling deformation by the shrinkage and residual stress in the weld line direction is one of the most serious deformation types. This paper is concerned with controlling buckling deformations for the thin plate fillet welds, by using the tensioning method. A numerical analysis was carried out to illustrate several dominant buckling modes due to compressive residual stress in the fillet weldsof thin plates. Then, weld tests were carried out for 20 specimens with varying plate thickness, and with different magnitudes and directions for the tension load. The results graphically represented to shaw the effect of the tensioning method in reducing the weld-induced deformation. From the present findings, it was seen that the tensioning method is a useful way to control weld-induced deformations in the fillet welds of thin plates.

장력법을 이용한 필릿용접변형의 감소에 관한 연구 (A Study on the Reduction of Fillet Welding Deformation by Applying the Tensioning Method)

  • 이주성;박재우
    • 대한조선학회논문집
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    • 제44권6호
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    • pp.590-597
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    • 2007
  • The portion of thin plate is expected to increases as to the development of design and fabrication technology. The weld-induced deformation is more serious in thin plates than in thick plates because heat affect zone of thin plates is wider than that of thick plates, and in addition internal and external constraints much more influence upon weld-induced deformation of thin plates. This paper is aimed at applying the mechanical tensioning method to fillet weld of thin plates to reduce the weld-induced deformation. For this purpose, fillet welding tests have been carried out for several thin plate specimens with varying plate thickness and magnitude of tensile load. From the present study, it has been found that the tensioning method is effective on reduction of weld-induced deformation.

Quantitative Analysis of Bayesian SPECT Reconstruction : Effects of Using Higher-Order Gibbs Priors

  • S. J. Lee
    • 대한의용생체공학회:의공학회지
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    • 제19권2호
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    • pp.133-142
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    • 1998
  • Bayesian SPECT 영상재구성에 있어서 정교한 형태의 사전정보를 사용할 경우 bias 및 variance와 같은 통계적 차원에서의 정량적 성능을 향상시킬 수 있다. 특히, "thin plate" 와 같은 고차의 smoothing 사전정보는 "membrane"과 같은 일반적인 다른 사전 정보에 비해 bias를 개선시키는 것으로 알려져 있다. 그러나, 이와 같은 장점은 영상재구성 알고리즘에 내재하는 hyperparameters의 값을 최적으로 선택하였을 경우에만 적용된다. 본 연구에서는 thin plate와 membrane의 두가지 대표적인 사전정보를 포함하는 영상재구성 알고리즘의 정량적 성능에 대해 집중 고찰한다. 즉, 알고리즘에 내재하는 hyperparameters 가 통계적 차원에서 bias와 variance에 어떠한 영향을 미치는지 관찰한다. 실험에서 Monte Carlo noise trials를 사용하여 bias와 variance를 계산하며, 각 결과를 ML-EM 및 filtered backprojection으로부터 얻어진 bias 및 variance와 비교한다. 결론적으로 thin plate와 같은 고차의 사전정보는 hyperparameters의 선택에 민감하지 않으며, hyperparameters 값의 전 범위에 걸쳐 bias를 개선시킴을 보인다. 걸쳐 bias를 개선시킴을 보인다.

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Slope plate 공법을 이용한 반응고 박판 및 제조 장치 개발 (Fabrication of Thin Plate of Semisolid Material using Slope Plate Process and Development of Fabrication Apparatus)

  • 구자윤;배정운;진철규;강충길
    • 한국주조공학회지
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    • 제32권1호
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    • pp.24-31
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    • 2012
  • In this study, semi-solid thin plate of A 356 aluminum alloy was fabricated by using slope plate apparatus and vacuum pressurization. Slope plate was used to produce semi-solid material with spheroidal microstructures. After molten metal was poured into the slope plate connected to the pouring hole of die, semi-solid material flowed into the die cavity by vacuum degree. The primary crystals of the cast metal became spheroidal. In order to increase the working pressure, gas pressurization of U shape was designed for fabrication of thin plate. For 3 bar of gas pressure and 60 mmHg of vacuum degree, thin plate was fabricated without defects on surface.

초박판 사출성형특성 분석을 위한 금형제작에 관한 연구 (A Study of Injection Mold Manufacturing for Ultra-Thin Walled Plate)

  • 이성희;고영배;이종원;김성규;양진석;허영무
    • Design & Manufacturing
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    • 제2권5호
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    • pp.11-15
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    • 2008
  • A micro-injection mold for ultra-thin-walled plate was considered in this work. The proposed mold system is for the fabrication of ultra-thin walled plastic plate with micro features by injection molding. As the injection molding of thin-walled plastic, which has the thickness under $400{\mu}m$, itself is not easy, the injection molding of the micro-features in the thin-walled structure is more complicated and difficult. To investigate the basic phenomenon of the ultra-thin walled part during the injection molding process, design of the part and mold system were performed in the present study. The injection molding and structural analysis of the suggested part and mold system were also performed. Consequently, injection molding system for ultra-thin walled plate with micro features were manufactured and presented.

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Optimum Weight in Spline for Surface Model

  • 손호웅;오석훈;김영경
    • 지구물리
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    • 제8권1호
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    • pp.23-33
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    • 2005
  • The digital surface model (DSM) is used for several purposes in photogrammetry, remote sensing and laser scanned data such as orthoimage production, contours erivation, extraction of height information. Creation of a surface model from point-clouds (3-D sparse points) that can be derived from stereo imagery and range data (e.g. laser scanned data) can be done with several mathematical interpolation models. In this paper, thin-plate-spline (TPS) is used for digital surface modeling. Determination of suitable weight is an important problem in thin-plate function for a surface. The Voronoi algorithm has been proposed as a method for determination of the weight in thin-plate-spline. In this paper, methods has been tested for different surfaces. The results show that thin-plate-spline can be independent of weight.

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