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IntroductionFlexiblecableswithlargesagareakindofspecialengineeringstructures.Theyareusedinoverheadtransmissionlineswithhighvoltage,aerialcablesfortransport,largespanstructuresinbridgesandcivilengineering[1,2].Theywillmoveinlargerangeunderwind,loaddesigned… 相似文献
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We present an extension to the subgradient algorithm to produce primal as well as dual solutions. It can be seen as a fast
way to carry out an approximation of Dantzig-Wolfe decomposition. This gives a fast method for producing approximations for
large scale linear programs. It is based on a new theorem in linear programming duality. We present successful experience
with linear programs coming from set partitioning, set covering, max-cut and plant location.
Received: June 15, 1998 / Accepted: November 15, 1999?Published online March 15, 2000 相似文献
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梁的弹塑性大挠度数值分析 总被引:8,自引:0,他引:8
采用分层法研究Timoshenko型直梁的弹塑性大挠度数值问题,由TL列式法建立梁的非线性平衡方程,采用mNR法求解.详细介绍了单元的切线刚度矩阵形成过程及求解步骤.解的情况令人满意. 相似文献
959.
Several TiO2 and γ‐Al2O3 supported catalyst systems were prepared by a novel way and characterized by X‐ray diffraction, Raman spectroscopy and BET surface area measurement. The results show: (1) all the samples, including MoO3/TiO2, WO3/TiO2, V2O5/TiO2, FeSO4/γ‐Al2O3, Al2 (SO4)3/γ‐Al2O3, K2CO3/‐Al2O3 and so on, prepared by impregnating TiO2·H2O or pseudo‐boehmite AlO(OH) with the active components then calcining at a high temperature exhibit much larger surface areas than that of pure TiO2 or γ‐Al2O3 calcined at the same temperature; (2) the surface area of the sample increases with the increase in the coverage of active component on the surface of the support; (3) when the content of active component reaches its utmost monolayer dispersion capacity, the surface area of the sample is the largest, and then decreases when the content of active component exceeds its dispersion threshold. 相似文献
960.
Subgrid nonlinear interaction and energy transfer are analyzed using direct numerical simulations of isotropic turbulence.
Influences of cutoff wave number at different ranges of scale on the energetics and dynamics have been investigated. It is
observed that subgrid-subgrid interaction dominates the turbulent dynamics when cut-off wave number locates in the energy-containing
range while resolved-subgrid interaction dominates if it is in the dissipation range. By decomposing the subgrid energy transfer
and nonlinear interaction into ‘forward’ and ‘backward’ groups according to the sign of triadic interaction, we find that
individually each group has very large contribution, but the net of them is much smaller, implying that tremendous cancellation
happens between these two groups. 相似文献