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941.
Proton collisions with the water dimer are studied using a nonadiabatic, direct, time‐dependent approach called electron nuclear dynamics (END). Fragmentation of the water dimer in collisions with protons at energies of 5.0, 1.0 keV and 200 eV is the primary aim of this initial study of water clusters using END. We report on the initial fragmentation dynamic, that is, for times less than 200 fs. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 相似文献
943.
We characterize active redundancy through compensator transform and use the reverse rule of order 2 (RR2) property between compensator processes to investigate the problem of where to allocate a spare in a k-out-of-n:F system of dependent components through active redundancy. 相似文献
944.
阐述了应用Stolz定理求数列极限时应注意的问题,并从Stolz定理与L’Hospital法则相互呼应的角度,指出了∞∞型的L’Hospital法则可改进为*∞型.这些工作,不但扩大了其应用范围,而且还给求极限带来许多方便. 相似文献
945.
Bingwu Wang 《Journal of Mathematical Analysis and Applications》2006,323(2):1365-1372
The fuzzy intersection rule for Fréchet normal cones in Asplund spaces was established by Mordukhovich and the author using the extremal principle, which appears more convenient to apply in some applications. In this paper, we present a complete discussion of this rule in various aspects. We show that the fuzzy intersection rule is another characterization of the Asplund property of the space. Various applications are considered as well. In particular, a complete set of fuzzy calculus rules for general lower semicontinuous functions are established. 相似文献
946.
947.
We analyze the effects of voter coordination on the equilibrium of voting games. Specifically, we analyze the concepts of
strong equilibrium and coalition-proof equilibrium for plurality rule and runoff rule elections. We characterize these equilibria
in the three candidate case, and provide results for important special cases in the general multicandidate case.
相似文献
948.
In this paper, the time-scaled trapezoidal integration rule for discretizing fractional order controllers is discussed. This interesting proposal is used to interpret discrete fractional order control (FOC) systems as control with scaled sampling time. Based on this time-scaled version of trapezoidal integration rule, discrete FOC can be regarded as some kind of control strategy, in which strong control action is applied to the latest sampled inputs by using scaled sampling time. Namely, there are two time scalers for FOC systems: a normal time scale for ordinary feedback and a scaled one for fractional order controllers. A new realization method is also proposed for discrete fractional order controllers, which is based on the time-scaled trapezoidal integration rule. Finally, a one mass position 1/sk control system, realized by the proposed method, is introduced to verify discrete FOC systems and their robustness against saturation non-linearity. 相似文献
949.
本指出了[4]的一个错误。用最速下降规则,给出了选择割平面的一个新方法。一个复杂的例子说明,该方法有一定的实用价值。 相似文献
950.
Liping Yu Zhengbiao Zhang Xinrong Chen Wei Zhang Jianhong Wu Zhenping Cheng Jian Zhu Xiulin Zhu 《Journal of polymer science. Part A, Polymer chemistry》2008,46(2):682-691
A novel optically active monomer, 6‐{4‐[4‐(1‐phenyl‐1H‐tetrazol‐5‐yloxy)‐phenylazo] ‐phenoxy}‐hexyl methacrylate (PTPPHMA) bearing tetrazole and azobenzol moieties, was synthesized and polymerized by reversible addition‐fragmentation chain transfer (RAFT) polymerization using 2‐cyanoprop‐2‐yl dithiobenzoate (CPDB) as the RAFT agent and 2, 2′‐azobis(isobutyronitrile) (AIBN) as the initiator. Well‐defined optically active photochromic polyPTPPHMA(PPTPPHMA) was obtained. “Living”/controlled characteristics were observed in the polymerization: well‐controlled molecular weights (Mns), narrow molecular weight distributions (Mw/Mn) of the polymers and successful chain‐extension of PPTPPHMA with styrene (St) as the second monomer. The photochemical interconversion between trans and cis isomers of PPTPPHMA in N,N′‐dimethyl formamide (DMF) solution was explored under irradiation of ultraviolet light. The photoinduced birefringence on the thin films of PPTPPHMA was investigated. A maximum birefringence of 0.1 was obtained, and no significant change of profiles of the birefringence after several cycles of writing/erasing/rewriting sequences was observed. The surface‐relief‐gratings (SRGs) were induced on the polymer films by interference of Kr+ laser beams at 413.1 nm with 35 mW/cm2 intensity, the diffraction efficiencies from SRGs were measured to be in the range of 2.0–2.5%. The atomic force microscopy (AFM) results showed the gratings produced on the surfaces of the polymer film. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 682–691, 2008 相似文献