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951.
952.
Ging-Ho Hsiue Wen-Kuei Huang Hsiao-Lung Chu 《Journal of polymer science. Part A, Polymer chemistry》1989,27(13):4397-4402
Differential scanning calorimetry was used to trace the heat of decomposition of the peracid groups (ΔHd) in the oxidized EVA-g-AA resin. From the correlation between ΔHd and the oxidation capacity measured by iodometry, it was found that 35 ± 5 cal of energy evolved per miliequivalent of peracid group decomposed. The ΔHd values are also useful in finding the optimum condition for oxidation of acid groups and can be used to investigate the distribution of active peracid groups across the matrix. The stability and the activation energy of decomposition of grafted type peracid resin were also studied, where the activation energy of decomposition was calculated to be 13.4 kcal/mol. 相似文献
953.
In this article, we show the existence of intertwined basins of attraction for a class of prey-predator systems, which improves the extant results by deleting some crucial and hard testing conditions. 相似文献
954.
In this article, the authors study some basic properties of the so-called quasilinear- additive functions, and some applications to the special functions of quasiconformal analysis are specified. 相似文献
955.
Jifeng Chu 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(3-4):1983-1992
We study the existence of positive bound states of non-autonomous systems of nonlinear Schrödinger equations. Both the singular case and the regular case are discussed. The proof is based on a nonlinear alternative principle of Leray–Schauder. 相似文献
956.
Singular spectrum analysis has recently become an attractive tool in a broad range of applications. Its main mechanism of alternating between rank reduction and Hankel projection to produce an approximation to a particular component of the original time series, however, deserves further mathematical justification. One paramount question to ask is how good an approximation that such a straightforward apparatus can provide when comparing to the absolute optimal solution. This paper reexamines this issue by exploiting a natural parametrization of a general Hankel matrix via its Vandermonde factorization. Such a formulation makes it possible to recast the notion of singular spectrum analysis as a semi-linear least squares problem over a compact feasible set, whence global optimization techniques can be employed to find the absolute best approximation. This framework might not be immediately suitable for practical application because global optimization is expectedly more expensive, but it does provide a theoretical baseline for comparison. As such, our empirical results indicate that the simpler SSA algorithm usually is amazingly sufficient as a handy tool for constructing exploratory model. The more complicated global methods could be used as an alternative of rigorous affirmative procedure for verifying or assessing the quality of approximation. 相似文献
957.
In this paper, we first give a direct construction of the ℕ-measure of a continuous state branching process. Then we prove, with the help of this ℕ-measure, that any continuous state branching process with immigration can be constructed as the independent sum of a continuous state branching process (without immigration), and two immigration parts (jump immigration and continuum immigration). As an application of this construction of a continuous state branching process with immigration, we give a proof of a necessary and sufficient condition, first stated without proof by M. A. Pinsky [Bull. Amer. Math. Soc., 1972, 78: 242–244], for a continuous state branching process with immigration to a proper almost sure limit. As another application of the ℕ-measure, we give a “conceptual” proof of an L log L criterion for a continuous state branching process without immigration to have an L 1-limit first proved by D. R. Grey [J. Appl. Prob., 1974, 11: 669–677]. 相似文献
958.
The learning approach of empirical risk minimization (ERM) is taken for the regression problem in the least square framework. A standard assumption for the error analysis in the literature is the uniform boundedness of the output sampling process. In this paper we abandon this boundedness assumption and conduct error analysis for the ERM learning algorithm with unbounded sampling processes satisfying an increment condition for the moments of the output. The key novelty of our analysis is a covering number argument for estimating the sample error. 相似文献
959.
In this article, we deal with the notion of the envelopes of homotopies which is the generalized version of functional envelopes in discrete dynamical systems. We prove the stability for envelopes of homotopies in complete normed algebra and we get the stabilities of the derivation and the extended derivation for the notion in the spaces. 相似文献
960.
Miao-Kun Wang Yu-Ming Chu Song-Liang Qiu Yue-Ping Jiang 《Journal of Approximation Theory》2012,164(7):928-937
In this paper, we present several bounds for the perimeter of an ellipse, which improve some well-known results. 相似文献