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991.
The main result of the present note states that it is consistent with the ZFC axioms of set theory (relying on Martin's Maximum MM axiom), that every Asplund space of density character ω1 has a renorming with the Mazur intersection property. Combined with the previous result of Jiménez and Moreno (based upon the work of Kunen under the continuum hypothesis) we obtain that the MIP renormability of Asplund spaces of density ω1 is undecidable in ZFC. 相似文献
992.
The study of the analytic structure of nonlinear ordinary and partial differential equations is shown to provide a unified
approach to determining their properties and finding their solutions.
A course of lectures delivered at the School on Chaos and Nonlinear Dynamics held at the Indian Institute of Science, Bangalore,
India (June 24th–July 18th 1987) 相似文献
993.
刻划了赋序列范数的矢值B anach序列空间ss(E)的强暴露性和暴露性,给出了它们的判据. 相似文献
994.
The cyclic projections algorithm is an important method for determining a point in the intersection of a finite number of closed convex sets in a Hilbert space. That is, for determining a solution to the “convex feasibility” problem. This is the third paper in a series on a study of the rate of convergence for the cyclic projections algorithm. In the first of these papers, we showed that the rate could be described in terms of the “angles” between the convex sets involved. In the second, we showed that these angles often had a more tractable formulation in terms of the “norm” of the product of the (nonlinear) metric projections onto related convex sets.In this paper, we show that the rate of convergence of the cyclic projections algorithm is also intimately related to the “linear regularity property” of Bauschke and Borwein, the “normal property” of Jameson (as well as Bakan, Deutsch, and Li’s generalization of Jameson’s normal property), the “strong conical hull intersection property” of Deutsch, Li, and Ward, and the rate of convergence of iterated parallel projections. Such properties have already been shown to be important in various other contexts as well. 相似文献
995.
Let 1 ≤ p ≤ ∞. A subset K of a Banach space X is said to be relatively p ‐compact if there is an 〈xn 〉 ∈ ls p (X) such that for every k ∈ K there is an 〈αn 〉 ∈ lp ′ such that k = σ∞n=1 αn xn . A linear operator T: X → Y is said to be p ‐compact if T (Ball (X)) is relatively p ‐compact in Y. The set of all p ‐compact operators Kp (X, Y) from X to Y is a Banach space with a suitable factorization norm κp and (Kp , κp ) is a Banach operator ideal. In this paper we investigate the dual operator ideal (Kd p , κd p ). It is shown that κd p (T) = πp (T) for all T ∈ B (X, Y) if either X or Y is finite‐dimensional. As a consequence it is proved that the adjoint ideal of Kd p is Ip ′, the ideal of p ′‐integral operators. Further, a composition/decomposition theorem Kd p = Πp K is proved which also yields that (Πmin p )inj = Kd p . Finally, we discuss the density of finite rank operators in Kd p and give some examples for different values of p in this respect. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
袁中许 《数学的实践与认识》2008,38(1):27-32
针对知识产权屡禁不止的侵权行为现状,运用模糊数学、数理统计方法和博弈论原理,从知识产权保护和侵犯双方效用及模型出发,以系统和动态的视角对双方行为进了博弈分析.研究结果表明保护与侵犯构成为一对均衡策略状态,其主要原因在于一定条件下,保护方期望的效用均衡处于低水平态势,从而提出在效用模糊因子的调整中不断提高保护方的动态效用水平是推进有效保护知识产权的动力途径. 相似文献
997.
On the use of fuzzy inference techniques in assessment models: part I—theoretical properties 总被引:2,自引:0,他引:2
An assessment model is a mathematical model that produces a measuring index, either in the form of a numerical score or a
category to a situation/object, with respect to the subject of measure. From the numerical score, decision can be made and
action can be taken. To allow valid and useful comparisons among various situations/objects according to their associated
numerical scores to be made, the monotone output property and the output resolution property are essential in fuzzy inference-based
assessment problems. We investigate the conditions for a fuzzy assessment model to fulfill the monotone output property using
a derivative approach. A guideline on how the input membership functions should be tuned is also provided. Besides, the output
resolution property is defined as the derivative of the output of the assessment model with respect to its input. This derivative
should be greater than the minimum resolution required. From the derivative, we suggest improvements to the output resolution
property by refining the fuzzy production rules. 相似文献
998.
Antonio Roviello Fabio Borbone Antonio Carella Rosita Diana Giuseppina Roviello Barbara Panunzi Antonio Ambrosio Pasqualino Maddalena 《Journal of polymer science. Part A, Polymer chemistry》2009,47(10):2677-2689
The synthesis and the chemical physical characterization of new photoluminescent (PL) chromophores and polymers are reported. Chromophores (oligo‐PPV symmetric derivatives ending with amino groups) are strong blue emitters with a PL quantum yield of ~70% in dioxane solution. They have been used to prepare polyamides by reaction with aliphatic acyl dichlorides in which emitting and non emitting units are alternated. PL properties of the synthesized polyamides have been evaluated in solution and reveal a strong blue emission (PL quantum yield ~60%), To increase the solubility of these systems, oligomers have been purposely prepared and then characterized. They show a peculiar white emission when excited in DMF solution; to get insight into this interesting behavior, asymmetric monoacetylated chromophores have been prepared as model compounds for the chromophoric end groups of the polyamide chains. The emission spectra of these compounds reveal a broad excimeric yellow emission which is responsible, along with the blue emission of the inner chromophoric units, of the overall white emission of the oligomers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2677–2689, 2009 相似文献
999.
Xinjian Cheng Sie Chin Tjong Qiang Zhao Robert K. Y. Li 《Journal of polymer science. Part A, Polymer chemistry》2009,47(18):4547-4554
This article presents a facile method to prepare silver/polystyrene composite microspheres. In this approach, monodispersed polystyrene (PS) particles were synthesized with carboxyl acid groups on the surfaces of the PS particles via dispersion polymerization at first. With the addition of [Ag(NH3)2]+ to the PS dispersion, [Ag(NH3)2]+ was absorbed to the surfaces of the PS particles, and then by heating the system, [Ag(NH3)2]+ complex ions were reduced to silver to form the Ag/PS composite microspheres. In the synthesis of PS dispersion, PVP was used as dispersant to stabilize the PS particles, it also acted as reducing agent in the reduction of [Ag(NH3)2]+ complex ions to silver, so no additional reducing agent was needed. The resulting composite microspheres were characterized by TEM, SEM, XPS, and XRD. The catalytic properties and surface‐enhance Raman scattering (SERS) was studied as well. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4547–4554, 2009 相似文献
1000.
A study of the d.ynamical fluctuation properties at various c.m.energies in e~ e~- collisions is performed using the Monte Carlo method.The results suggest that,after the normalized factorial moments of 3-dimensional phase space are analyzed using an isotropical phase space partition,the NFM describing non- linear dynamical properties show a power-law scaling,i.e.,the dynamical fluctuations in higher dimensional phase space are isotropic.For c.m.energies s~(1/2)≤80 GeV,the scaling exponentsφ_q increase rapidly with the c.m.energy and for c.m.energies s~(1/2)>80 GeV,theφ_q gradually saturate. 相似文献