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951.
《Optimization》2012,61(3):193-209
In this paper, we study regularity and optimality conditions for the BLPP by using a marginal function formulation, where the marginal function is defined by the optimal value function of the lower problem. We address the regularity issue by exploring the structure of the tangent cones of the feasible set of the BLPP. These regularity results indicate that the nonlinear/nonlinear BLPP is most likely degenerate and a class of nonlinear/linear BLPP is regular in the conventional sense. Existence of exact penalty function is proved for a class of nonlinear/linear BLPP. Fritz-John type optimality conditions are derived for nonlinear BLPP, while KKT type conditions are obtained for a class of nonlinear/linear BLPP in the framework of nonsmooth analysis. A typical example is examined for these conditions and some applications of these conditions are pointed out  相似文献   
952.
In this article, we consider interior regularity for weak solutions to nonlinear elliptic systems of divergence type with Dini continuous coefficients under natural growth condition for the case 1 < m < 2. All estimates in the case of m ≥ 2 is no longer suitable, and we can't obtain the Caccioppoli's second inequality by using these techniques developed in the case of m ≥ 2. But the Caccioppoli's second inequality is the key to use A-harmonic approximation method. Thus, we adopt another technique introduced by Acerbi and Fcsco to overcome the difficulty and we also overcome those difficulties due to Dini condition. And then we apply the A-harmonic approximation method to prove partial regularity of weak solutions.  相似文献   
953.
In this paper, the problem of solving the two-dimensional diffusion equation subject to a non-local condition involving a double integral in a rectangular region is considered. The solution of this type of problems are complicated. Therefore, a simple meshless method using the radial basis functions is constructed for the non-local boundary value problem with Neumann’s boundary conditions. Numerical examples are included to demonstrate the reliability and efficiency of this method. Also Ne and root mean square errors are obtained to show the convergence of the method.  相似文献   
954.
955.
956.
CMOS电路总剂量效应最劣偏置甄别   总被引:1,自引:1,他引:0       下载免费PDF全文
采用电路分析和解析建模方法研究了CMOS电路中甄别总剂量效应最劣辐照与测试偏置的问题。通过引入小规模模拟电路和数字电路的例子进行具体分析,获取了不同电路的最劣偏置情况。对于数字电路,引入了敏感因子的概念用于定量计算不同辐照与测试偏置组合下电路的总剂量效应敏感程度。利用实测数据或电路仿真结果对甄别结果进行了一一验证,得到相一致的结论,证明了该研究思路的正确性。  相似文献   
957.
Three coordination polymers, {[Co(C10H5N3O5)(H2O)2]·H2O}n (1), {[Mn3(C10H5N3O5)2Cl2(H2O)6]·2H2O}n (2), and {[Cu3(C10H4N3O5)2(H2O)3]·4H2O}n (3), based on a T-shaped tripodal ligand 4-(4,5-dicarboxy-1H-imidazol-2-yl)pyridine 1-oxide (H3DCImPyO), were synthesized under hydrothermal conditions. The polymers showed diverse coordination modes, being characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray structure analysis. In 1, the HDCImPyO2? generated a 1-D chain by adopting a μ2-kN, O : kN′, O′ coordination mode to bridge two Co(II) ions in two bis-N,O-chelating modes. In 2, the HDCImPyO2? adopted a μ3-kN, O : kO′, O′′ : O′′′ coordination mode to bridge two crystallographically independent Mn(II) ions, forming a 2-D hcb network with {63} topology. In 3, by adopting μ4-kN, O : kO′, O′′ : kN′′, O′′′ : O′′′′ coordination, DCImPyO3? bridged three crystallographically independent Cu(II) ions to form a 3-D framework having the stb topology.  相似文献   
958.
Under hydrothermal conditions, reaction of Cu(II)/Cd(II) salts with 1,5-naphthalenedisulfonate (1,5-NDS) and 4,5-diazafluoren-9-one (dafo) afforded [Cu(dafo)2(1,5-NDS)]n (1) and [Cd(dafo)2(1,5-NDS)]n (2), respectively. The compounds were characterized by elemental analysis, IR, PXRD, TG-DSC, and single-crystal X-ray diffraction. Both 1 and 2, which are the first M(II)-1,5-NDS-dafo systems, exhibit 3-D supramolecular structures generated by 1-D chains via C–H?O hydrogen bonds and ππ interactions. Solid-state photoluminescence properties of both 1 and 2 were investigated with emission bands at 426–496?nm (λ ex?=?280, 270?nm for 1 and 2, respectively).  相似文献   
959.
For solving large-scale unconstrained minimization problems, the nonlinear conjugate gradient method is welcome due to its simplicity, low storage, efficiency and nice convergence properties. Among all the methods in the framework, the conjugate gradient descent algorithm — CG_DESCENT is very popular, in which the generated directions descend automatically, and this nice property is independent of any line search used. In this paper, we generalize CG_DESCENT with two Barzilai–Borwein steplength reused cyclically. We show that the resulting algorithm owns attractive sufficient descent property and converges globally under some mild conditions. We test the proposed algorithm by using a large set of unconstrained problems with high dimensions in CUTEr library. The numerical comparisons with the state-of-the-art algorithm CG_DESCENT illustrate that the proposed method is effective, competitive, and promising.  相似文献   
960.
A 2-D coordination polymer with mixed ligands, [Zn2(BDC)(4,4′-bipy) (HCOO)2] (1) (BDC, 1,4-benzenedicarboxylate; 4,4′-bipy, 4,4′-bipyridine), has been synthesized by solvothermal reaction. Compound 1 provides the first coordination polymer structure constructed by bridging BDC, 4,4′-bipy, and formate. Both BDC and 4,4′-bipy link zincs alternatively, resulting in a zigzag coordination chain; adjacent chains are further linked by formates to form an infinite extended 2-D folding screen layer. The synthesis mechanism and fluorescence property are discussed.  相似文献   
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