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71.
Ajit Patel Amiya K. Pani Neela Nataraj 《Numerical Methods for Partial Differential Equations》2008,24(6):1460-1484
In this article a standard mortar finite element method and a mortar element method with Lagrange multiplier are used for spatial discretization of a class of parabolic initial‐boundary value problems. Optimal error estimates in L∞(L2) and L∞(H1)‐norms for semidiscrete methods for both the cases are established. The key feature that we have adopted here is to introduce a modified elliptic projection. In the standard mortar element method, a completely discrete scheme using backward Euler scheme is discussed and optimal error estimates are derived. The results of numerical experiments support the theoretical results obtained in this article. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008 相似文献
72.
Calix[4]arene derivatives bearing anionic carboxylato groups at the upper rim (p-carboxylatocalix[4]arenes) are able to ‘grab’ paraquat dicationic guest through an induced-fit mechanism, which originates from the conformational mobility of calixarene skeleton. 相似文献
73.
74.
R. Andreani E. G. Birgin J. M. Martínez M. L. Schuverdt 《Mathematical Programming》2008,111(1-2):5-32
Two Augmented Lagrangian algorithms for solving KKT systems are introduced. The algorithms differ in the way in which penalty
parameters are updated. Possibly infeasible accumulation points are characterized. It is proved that feasible limit points
that satisfy the Constant Positive Linear Dependence constraint qualification are KKT solutions. Boundedness of the penalty
parameters is proved under suitable assumptions. Numerical experiments are presented.
The authors were supported by PRONEX - CNPq / FAPERJ E-26 / 171.164/2003 - APQ1, FAPESP (Grants 2001/04597-4, 2002/00094-0,
2003/09169-6, 2002/00832-1 and 2005/56773-1) and CNPq. 相似文献
75.
Lubov' V. Snegur Yury S. Nekrasov Nataliya S. Sergeeva Zhanna V. Zhilina Vera V Gumenyuk Zoya A. Starikova Alexander A. Simenel Nataliya B. Morozova Irina K. Sviridova Valery N. Babin 《应用有机金属化学》2008,22(2):139-147
The toxicity of ferrocenylethyl benzotriazole ( 1 ) and other ferrocene compounds including ferrocenylmethyl benzimidazoles ( 4,5,6,11 ), ferricenium salts ( 3,9,10 ) and ferrocenylmethyl adenine ( 7 ), was studied. All ferrocene complexes under investigation showed low or medium toxicities. On the basis of an earlier model of chemical carcinogenesis, the antitumor activity of ferrocenylalkyl azoles 1, 8 and ferricenium salts 9, 10 was studied in vivo in the so‐called sub‐capsular test on human tumors. This effectiveness was compared with that of cisplatin. A series of ferrocenylalkyl azoles were synthesized by interacting azoles either with α‐hydroxyalkyl ferrocenes FcC(OH)R1R2 in organic solvent in the presence of aqueous HBF4 in quantitative yields or with trimethyl(aminomethyl)ferrocene iodide in an aqueous‐basic medium in good yields. The X‐ray determinations of molecular and crystal structures of α‐(1‐benzotriazolyl)ethylferrocene ( 1 ) and α‐(1‐naphthatriazolyl)ethylferrocene ( 12 ) were performed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
77.
The hadronic and string cascade model and the corresponding event generator LUCIAE are used to study systematically the production
of the grey particles in (14.6, 60 and 200A GeV)0 + Em, (2004 GeV)Si + Em, (200A GeV)S + Em and (11.6A GeV)Au + Em reactions. The dependences of the mean multiplicity,
the multiplicity distributions and the polar angular distributions of the grey particles on the incident energy, the projectile
mass and the collision centrality observed in emulsion experiments, respectively, are all reproduced by LUCIAE calculations.
In addition the effects of the rescattering on the grey particle production are also investigated.
Project supported by the National Natural Science Foundation of China (Grant Nos. 19575071 and 19875019) and DFG of Germany. 相似文献
78.
《数学实验》课程建设的认识与实践 总被引:22,自引:0,他引:22
我们认为 :数学实验 ,就是对数学进行折腾 .我们提出一些饶有趣味而又有深刻背景的问题 ,让学生尝试自己去解决 ,借助于计算机 ,自己动手去折腾 ,在折腾过程中学习 ,观察现象和结果 ,猜测和验证规律 ,尝试和体验数学的探索、发现和应用 相似文献
79.
80.
Li-Lian Gao Nezih Altay E. Powell Robinson 《Mathematical and Computer Modelling》2008,47(11-12):1254-1263
In the coordinated lot-size problem, a major setup cost is incurred when at least one member of a product family is produced and a minor setup cost for each different item produced. This research consolidates the various modeling and algorithmic approaches reported in the literature for the coordinated replenishment problem with deterministic dynamic demand. For the two most effective approaches, we conducted extensive computational experiments investigating the quality of the lower bound associated with the model’s linear programming relaxation and the computational efficiency of the algorithmic approaches when used to find heuristic and optimal solutions. Our findings indicate the superiority of the plant location type problem formulation over the traditional approach that views the problem as multiple single-item Wagner and Whitin problems that are coupled by major setup costs. Broader implications of the research suggest that other classes of deterministic dynamic demand lot-size problems may also be more effectively modeled and solved by adapting plant location type models and algorithms. 相似文献