12 resultados para R-package

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A practical package technique for temperature independent Fiber Bragg grating sensor is proposed. A uniform strength cantilever with two FBG attached on the upper and lower surfaces was utilized as the key element. By detecting two wavelengths differential output, the applied force can be obtained and temperature effects can be eliminated. Experiment results show the sensor has linear response and output signal uctuates less than 12pm as temperature changes from -10 degrees C to 50 degrees C. The maximum thermal error is less than 0.3% of the full measurement range.

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From St15 micro-carbon deep drawing steel sheets, two sets of samples with (r) over bar variant and Deltar constant, and (r) over bar constant and Deltar variant, were selected to carry out texture measurement and ODF analysis. A description of the texture characteristics and an investigation on the effect of the main textures on the (r) over bar and Deltar values were given. The results show that in the tested steel sheets no desired gamma < 111 > parallel to ND orientation line appears but gamma' orientation line located at <()over bar>=0-90 degrees, theta =19 degrees and phi =45 degrees, and L orientation line located around gamma < 111 > parallel to ND orientation line which spirally rotates from Psi =0 degrees, theta =54.7 degrees and phi =62.7 degrees to Psi =90 degrees, theta =40 degrees and phi =45 degrees occur. Among them, the L orientation line has a main influence on the (r) over bar value and the stronger the texture density, the higher the (r) over bar value is, but is somewhat detrimental to the Deltar value; at the same time, the gamma' orientation line has a major effect on the Deltar value in an opposite way, but is somewhat deteriorative to the (r) over bar value. A strong L orientation line superposed by a relatively strong gamma' orientation line may produce fine (r) over bar and Deltar values.

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介绍一种可用于微电子封装局部应变场分析的实验/计算混合方法,该方法结合了有限元的整体/局部模型和实时的激光云纹干涉技术,利用激光云纹干涉技术所测得的应变场来校核有限元整体模型的计算结果,并用整体模型的结果作为局部模型的边界条件,对实验难以确定的封装结构局部位置的应力、应变场进行分析.用这种方法对可控坍塌倒装封装结构在热载荷作用下焊球内的应变场分布进行了分析,结果表明该方法能够提供封装结构内应力-应变场分布的准确和可靠的结果,为微电子封装的可靠性分析提供重要的依据. For the reliability analysis of electronic packages, strains in very localized areas, such as an interconnection or a corner, need to be determined. In this paper, a modified hybrid method of global/local modeling and real time moire interferometry is presented. In this method, a simplified, coarsely meshed global model is developed to get rough information about the deformation of the microelectronic package. In order to make sure the global model has been reasonably simplified and the material properties ...

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In order to capture shock waves and contact discontinuities in the field and easy to program with parallel computation a new algorithm is developed to solve the N-S equations for simulation of R-M instability problems. The method with group velocity control is used to suppress numerical oscillations, and an adaptive non-uniform mesh is used to get fine resolution. Numerical results for cylindrical shock-cylindrical interface interaction with a shock Mach number Ms=1.2 and Atwood number A=0.818, 0.961, 0.980 (the interior density of the interface/outer density p(1)/p(2) = 10, 50, 100, respectively), and for the planar shock-spherical interface interaction with Ms=1.2 and p(1)/p(2) = 14.28are presented. The effect of Atwood number and multi-mode initial perturbation on the R-M instability are studied. Multi-collisions of the reflected shock with the interface is a main reason of nonlinear development of the interface instability and formation of the spike-bubble structures In simulation with double mode perturbation vortex merging and second instability are found. After second instability the small vortex structures near the interface produced. It is important factor for turbulent mixing.

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Three kinds of new nickel(II) complexes of alpha-isoxazolylazo-beta-diketones with blue-violet light absorption were synthesized. Their structures were postulated based on elemental analysis, MS and FT-IR spectra. Smooth films on K9 glass substrates were prepared using the spin-coating method. The absorption properties and thermal stability of these complexes were discussed. The static optical recording test for high density digital versatile disc-recordable (HD-DVD-R) system was also studied. (c) 2005 Elsevier B.V. All rights reserved.

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本文描述使用温梯法(TGT)生长(1-↑102)方向的白宝石单晶,应用X射线双晶摇摆曲线(XRC)测定了晶体内部的完整性,再利用KOH熔体腐蚀出样品的r面(1-↑102)上的位错蚀坑,借助扫描电子显微镜(SEM)进行观察,发现r面白宝石的位错腐蚀坑呈等腰三角形,并且有台阶状结构,并分析了位错的成因。

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r面(0112)蓝宝石晶体可用作制备非极性GaN薄膜的衬底。采用温度梯度法(temperature gradient technique,TGT)和导模法(edge-defined film-fed crystal growth,EFG)生长了质量良好的r面蓝宝石晶体。利用双晶衍射、光学显微镜、光谱仪观察和分析了晶体的结构和缺陷。结果表明:TGT法生长的r蓝宝石晶体的双晶摇摆曲线对称性好,半高宽值仅为18 rad.s,位错密度为4×103 cm-2,透过率达83%,晶体质量好。与TGT法相比,EFG法生长的r面蓝宝石晶体的结构完整性较差,位错密度为5×105 cm-2,透过率仅为75%。但是EFG法具有晶体生长速度快,后期加工成本低的优点。