• 제목/요약/키워드: flat top

검색결과 240건 처리시간 0.025초

SMC 압축성형의 열 및 유동에 관한 실험적 연구 (An Experimental Study on Heat Transfer and Flow in Compression Molding of SMC)

  • 김기택;정진호;임용택
    • 대한기계학회논문집
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    • 제18권9호
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    • pp.2386-2395
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    • 1994
  • An experimental study on heat transfer and flow in compression molding of clss-B and A SMC(Sheet Molding Compounds) in a flat plate and a cross-sectional T-shape was carried out. The temperature was measured with thermocouples at two locations in the 4 layered SMC charge and pressure was measured at the center of the top mold during compression molding. Three different mold speeds, 15, 45, 50 mm/min and two different mold temperature, $130^{\circ}C{\;}and{\;}150^{\circ}C$ were used for compression molding experiments. Experiments with different colored SMC layers were used to study flow patterns at various compression stages. In oder to predict the pressure and load in SMC compression molding, slab method was used. The predicted values of pressure and load from the slab analysis were compared well with the measured data.

『주례(周禮)』 주(注)·소(疏)를 통해 논의된 도성건설(都城建設)의 핵심과 평면적 형태해석의 비판적 검토 (Rites of Zhou Core Values of City Building and Critical Review of Flat Conformational Analysis through Its Annotations)

  • 강서연
    • 건축역사연구
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    • 제25권3호
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    • pp.7-22
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    • 2016
  • Of all the annotations of Rites of Zhou for 2,000 years, there is no single line of history of ore contents related to city building in its current perspective. This is because the definitive evidence of the interpretation of related phrases is regarded as top-level guidelines called "辨方正位(Byeonbang-Jeongwi)", and their specific contents have been discussed in '匠人建國(Jangin-Geonguk)'. The phrases of '匠人營國(Jangin-Yeongguk)', considered to be the key buzzword related to city building, must be reconsidered for these reasons. As such, this paper strives to analyze the system of logic formed by consistent interpretation that flowed for 2,000 years from Han to Qing dynasties, and to discover the principles of city building used in Confucian classics.

유한요소법에 의한 온도 하중의 해석 (A Finite Element Analysis Of Thermal Load On The Concrete Highway Pavement)

  • 조병완
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1991년도 봄 학술발표회 논문집
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    • pp.26-28
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    • 1991
  • In the recent years, a rigid pavement composed of a flat concrete slab has ken constructed due to the desirable structural strength of concrete, durability and economy. However, despite of precise design and construction of concrete highway pavement, some sections of the 88 Olympic express highway, Jung-bu express highway, and Kyung-bu express highway, which have shown premature cracking, faulting, and pumping before the end of their intended service life, have already been viewed with great concerns by highway officials and engineers. Since environmental variations and traffic loads might be considered as major factors to cause pavement failure problems, the thermal load due to temperature variations between top and bottom surface of the concrete slab was highlighted to verify analytical behavior of concrete slab using the finite element method.

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TGV & ICE Series의 전두부 디자인 형상변천에 관한 연구 (A study on the Changes of TGV & ICE Series' Nose Shape)

  • 이희엽;홍석기;나희승
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.1835-1842
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    • 2007
  • The purpose of this paper describes the changes of TGV & ICE series' nose shape by increasing train speed and according to the periodical characteristics. As the speed increases, the length of the nose shape trends to lengthen longer. But the nose shape length does not increase as speed improves by optimized nose shape to reduce aerodynamic drag and micro-pressure wave in tunnels. TGV & ICE series' nose shape can be classified into Advanced paraboloid type, Shape-nosed type, Organic double-edged type and Flat-nosed type by the advance research(the changes of Shinkansen vehicle' nose shape) of high speed railway. Because it trends to be diversified and characterized more and more. This paper analyzed and introduced as TGV & ICE series' nose shape by top 2 nation (Germany, France) and high speed railway in the past years(1980-2007) for their railway design trends by new positioning(Advance research).

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원통컵 디프드로잉 공정의 귀발생 예측 (Prediction of Earings in the Deep Drawing Processes of a Cylindrical Cup)

  • 이승열;이승열;금영탁;정관수;박진무
    • 소성∙가공
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    • 제4권3호
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    • pp.222-232
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    • 1995
  • The planar anisotripic FEM analysis for predicting earing profiles and draw-in amounts in the deep-drawing process is introduced. An implicit, incremental, updated Lagrangian formulation with a rigid-viscoplastic constitutive equation is employed. Contact and friction are considered through the mesh-based unit vector and normal contact pressure. The consistent full set of governing relations, which is comprising euilbrium and geometric constraint equations, is appropriately linearized. Barlat's strain-rate potential is employed, whose in-plane anisotropic properties are taken into account with anisotropic coefficients and potential parameters. The linear triangular membrane elements are used for depicting the formed sheet. In the numerical simulations of deep drawing processes of a flat-top cylindrical cup for 2090-T3 aluminum alloy sheet show good agreement with experiments, although some discrepancies were observed in the directional trend of cup height and thickness strains.

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80-MW 클라이스트론 부하용 200-MW 펄스 트랜스포머의 성능시험 (Performance Test of 200-MW Pulse Transformer for 80-MW Klystron Load)

  • 장성덕;오종석;손윤규;조무현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2167-2169
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    • 1999
  • A pulse transformer producing pulses with the peak power of 200-MW (400 kV 500 A at load side with $4.4{\mu}s$ flat-top) is required to drive the 80-MW pulsed klystron in the PLS linac. We have designed and manufactured the high power pulse transformer with 1 : 17 turn ratio. Its primary functions are to match the impedance of klystron tube to the modulators, and to provide step-up of the voltage. To obtain a fast rise time of the pulse voltage. Low leakage inductance and low distributed capacitance design is very important. In this paper, we discuss the equivalent circuit analysis of the pulse transformer, and present the full power performance test results of pulse transformer.

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역기전력을 고려 한 브러시레스 전동기의 토크리플 저감에 관한 구동 방식에 대한 연구 (A Torque Ripple Reduction Drive Strategy for Permanent Magnet Brushless DC Motor with Imperfect Back Electromotive Force)

  • 손도;남기용;이근호;홍정표
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.781-782
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    • 2006
  • This paper presents a drive strategy to reduce torque ripple of a permanent magnet Brushless DC Motor(BLDCM) with short $120^{\circ}$ flat top Back Electromotive Force(Back-EMF). In this strategy, the phase Back-EMF is divided into four sections. Then, in each section the phase current is regulated by corresponding PWM duty ratio to compensatethe torque ripple caused by imperfect Back-EMF. A program based on this strategy has been implemented in MATLAB@Simulink. The validity of the presented method is verified by simulation results.

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홀로그래픽 정보저장장치에서 디지털 이미지 마스크를 이용한 실시간 광량 제어 알고리즘 (Real Time Light Intensity Control Algorithm Using Digital Image Mask for the Holographic Data Storage System)

  • 김상훈;양현석;박영필
    • 정보저장시스템학회논문집
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    • 제6권1호
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    • pp.1-5
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    • 2010
  • Holographic data storage system(HDSS) has many noise sources - crosstalk, scattering and inter pixel interference, etc. Generally the intensity of a light generated from the laser source has Gaussian distribution and this ununiformity of light also can make the data page to have a low SNR. A beam apodizer is used to make the laser as a flat-top beam but the intensity distribution is not strictly uniform. The intensity of light can be controlled using image mask. In this paper the intensity distribution of light used for HDSS is controlled by a digital image mask. The digital image mask is changed arbitrarily in real-time with suggested algorithm for the HDSS.

Finite strip method in probabilistic fatigue analysis of steel bridges

  • Li, W.C.;Cheung, M.S.
    • Steel and Composite Structures
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    • 제2권6호
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    • pp.429-440
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    • 2002
  • A finite strip method is developed for fatigue reliability analysis of steel highway bridges. Flat shell strips are employed to model concrete slab and steel girders, while a connection strip is formed using penalty function method to take into account eccentricity of girder top flange. At each sampling point with given slab thickness and modulus ratio, a finite strip analysis of the bridge under fatigue truck is performed to calculate stress ranges at fatigue-prone detail, and fatigue failure probability is evaluated following the AASHTO approach or the LEFM approach. After the failure probability is integrated over all sampling points, fatigue reliability of the bridge is determined.

PV의 건축물 적용기법에 관한 연구 (A Study on the Application Method of Photovoltaic in Building)

  • 이응직;김회서
    • 한국태양에너지학회 논문집
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    • 제22권2호
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    • pp.1-10
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    • 2002
  • This study is a study on the building integrated method of Photovoltaic. It was analyzed into a basic installation condition and an integrated form in this study. And it was confirmed through the 3D simulation & drawing work of an integrated situation to the real domestic building. The Photovoltaic installation of the country to an optimal efficiency for the year must be installed to the due south with an angle of thirty degrees. And also a module spacing must be more than doubled from the bottom to the top of module to prevent from efficiency falling by a shadow of photovoltaic module in a roof setting of flat roof. If Photovoltaic module is an adequate material that is a basic requirement as a building's finishing material, it's not only an efficiency of alternation with an existing finishing material but also a building's design element.