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31.
用带误差项的Ishikawa迭代过程逼近φ-强增生算子的零点 总被引:18,自引:0,他引:18
本文使用新的分析技巧研究了一致光滑Banach空间中φ 强增生算子的零点逼近问题,所得结果改进和扩展了近期许多相应的结果 相似文献
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A computer simulation system of three-dimensional sensing with structured illumination is presented. It includes the generation of deformed fringe patterns from 3-D shapes and the reconstruction of 3-D shapes, conversely. Some experimental results of the deformed fringe pattern and the reconstructed object shapes are presented. We have also discussed the effect of some major system parameters on the measurement results and considered how to correct these parameters according to the measurement result of the standard plane. Using this simulation system, the major system parameters: environmental conditions, measurement accuracy and algorithm evaluation of the 3-D shape measurement system based on PMP, FTP, SPM, etc., can be researched. © 1997 Elsevier Science Ltd. All rights reserved. 相似文献
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The DTL tank is a multi-cell cavity.In a fabricated tank,the measured average axial field E0 for each cell may obviously deviate from the designed value.It is generally thought the deviation is due to the errors in fabrication and assembly.But it is not always true.In this paper,it is shown that the deviation may already exist before fabrication in some cases.It is partly due to the imperfection of the current design procedures.A new design method is introduced to reduce the deviation in the design stage. 相似文献
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The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper. 相似文献
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《Journal of computational chemistry》2017,38(17):1509-1514
We study the orbital‐dependence of three (parameter‐free) double‐hybrid density functionals, namely the PBE0‐DH, the PBE‐QIDH models, and the SOS1‐PBE‐QIDH spin‐opposite‐scaled variant of the latter. To do it, we feed all their energy terms with different sets of orbitals obtained previously from self‐consistent density functional theory calculations using several exchange‐correlation functionals (e.g., PBE, PBE0, PBEH&H), or directly with HF‐PBE orbitals, to see their effect on selected datasets for atomization and reaction energies, the latter proned to marked self‐interaction errors. We find that the PBE‐QIDH double‐hybrid model shows a great consistency, as the best results are always obtained for the set of orbitals corresponding to its hybrid scheme, which prompts us to recommend this model without any other fitting or reparameterization. © 2017 Wiley Periodicals, Inc. 相似文献
38.
Safe bounds in linear and mixed-integer linear programming 总被引:1,自引:0,他引:1
Current mixed-integer linear programming solvers are based on linear programming routines that use floating-point arithmetic. Occasionally, this leads to wrong solutions, even for problems where all coefficients and all solution components are small integers. An example is given where many state-of-the-art MILP solvers fail. It is then shown how, using directed rounding and interval arithmetic, cheap pre- and postprocessing of the linear programs arising in a branch-and-cut framework can guarantee that no solution is lost, at least for mixed-integer programs in which all variables can be bounded rigorously by bounds of reasonable size.
Mathematics Subject Classification (2000):primary 90C11, secondary 65G20 相似文献
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干涉仪在系统中固定产生的应力会影响干涉条纹的调制度.将干涉仪的非通光面与干涉仪材料性能相同的玻璃平板胶合,做为干涉仪上下面的安装面,可以消除安装过程中对干涉仪产生的应力.选取航天通用的铸钛材料做为支撑件,可以避免恶劣航天环境中金属件热膨胀对干涉仪的破坏,采用XM31胶垫对干涉仪运输过程进行保护.整个装调中采用微应力装调.对整个系统采用工程分析软件进行了理论力学分析.结果表明,这种结构设计是可行的.同时采用2XSA60-T1000-32WL振动台,根据有关规范要求输入振动载荷,进行了力学环境试验.试验前后整个系统干涉图的MTF值基本不变.证明这种干涉仪结构设计以及微应力装调方法在工程应用上是可行的. 相似文献