关于Liu-Owa积分算子的双重从属保持性质

本文研究了单位圆盘内关于Liu-Owa积分算子的多叶解析函数类的从属和超从属保持问题.利用微分从属的方法,获得了该类函数的中间型结果,推广和改进了一些已知结果.     

On the nonvanishing of someL-functions

The non-vanishing, at the centre of symmetry, of theL-function attached to an automorphic representation of GL(2) or its twists by quadratic characters has been extensively investigated, in particular by Waldspurger. The purpose of this paper is to outline a new proof of Waldspurger’s results. The automorphic representations of GL(2) and its metaplectic cover are compared in two different ways; one way is by means of a “relative trace formula”; the relative trace formula presented here is actually a generalization of the work of Iwaniec. This is the text of a lecture delivered in June 1987 in Paris at the Symposium in honour of R Godement. This work was supported in part by NSF grant DMS-85-02789.     

应用结构摄动策略的有分流换热网络优化

有分流节点非结构模型（NNM-SS）应用于换热网络优化时,因难以生成合适的分流结构而使优化陷入局部极值.根据NNM-SS的优化特点及网络结构中分流次数对费用的影响,提出结构摄动策略,并将其引入强制进化随机游走算法（RWCE-SS）.策略的主要思想为：在优化过程中,以一定的概率随机抽取一个无分流结构的换热器,并在该位置上生成一组新的分流结构以增加网络中的分流次数,通过对结构的摄动实现对算法搜索能力的提升.算例验证表明应用该策略改进的算法可获得更好的优化结果.     

A Chernoff–Savage result for shape:On the non-admissibility of pseudo-Gaussian methods

Chernoff and Savage [Asymptotic normality and efficiency of certain non-parametric tests, Ann. Math. Statist. 29 (1958) 972–994] established that, in the context of univariate location models, Gaussian-score rank-based procedures uniformly dominate—in terms of Pitman asymptotic relative efficiencies—their pseudo-Gaussian parametric counterparts. This result, which had quite an impact on the success and subsequent development of rank-based inference, has been extended to many location problems, including problems involving multivariate and/or dependent observations. In this paper, we show that this uniform dominance also holds in problems for which the parameter of interest is the shape of an elliptical distribution. The Pitman non-admissibility of the pseudo-Gaussian maximum likelihood estimator for shape and that of the pseudo-Gaussian likelihood ratio test of sphericity follow.     

Investment portfolio behavior of non-life insurers: A utility analysis

Non-life insurers often claim that they are lead to reach out for extremely risky assets in the composition of their investment portfolio when their underwriting results deteriorate. In this paper we develop a model which attempts to explain the real behavior of investment portfolios of non-life insurance companies. The model is extended to include several variables over which the analysis is completed, namely the underwriting result, the premiums, the funds generating coefficient. The model is then subjected to a comparative statics analysis in order to examine the behavior of the portfolio composition in response to changes in the above mentioned variables. We show that the arguments developed by non-life insurers are at least questionable and critically dependent upon the increase and/or decrease of risk aversion measures.     

Extremely low density self-assembled InAs/GaAs quantum dots

The self-assembled InAs/GaAs quantum dots (QDs) with extremely low density of 8×106 cm-2 are achieved using higher growth temperature and lower InAs coverage by low-pressure metal-organic chemical vapour deposition (MOVCD). As a result of micro-photoluminescence (micro-PL), for extremely low density of 8×106 cm-2 InAs QDs in the micro-PL measurements at 10 K, only one emission peak has been achieved. It is believed that the InAs QDs have a good potential to realize single photon sources.     

Weighted nonlinear phase shift with group velocity dispersion to assess the nonlinear penalty in C+L band long-haul fiber optical amplified transmission link

To assess the penalty due to nonlinear effect in C L band long-haul optical amplified transmission link,a new parameter of modified nonlinear phase shift (φD) is proposed,which is the accumulated nonlinear phase shift weighted by a normalized group velocity dispersion (GVD).Based on the numerical simulation result of broadband long-haul hybrid Raman/erbium-doped fiber amplified transmission line,it is validated that φD is more reasonable and suitable than the previous proposed nonlinear phase shift (φNL) for broadband applications.     

A new demodulation technique for optical fiber interferometric sensors with [3×3] directional couplers

Optical fiber interferometric sensors based on [3×3] couplers have been used in many fields. A new technique is proposed to demodulate output signals of this kind of sensors. The technique recovers the signal of interest by fitting coefficients of elliptic （Lissajous） curves between each fiber pair. Different from other approaches, this technique eliminates the dependence on the idealization of [3×3] coupler, provides enhanced tolerance to the variance of photoelectric converters, and is anti-polarization in a certain extent. The main algorithm has been successfully demonstrated both by numerical simulation and experimental result.     

Bounds,monotonicity, uniqueness,and analytical calculation of a class of similarity solutions for the fluid flow over a nonlinearly stretching sheet

Invoking some estimates obtained in [F.T. Akyildiz et al., Mathematical Methods in the Applied Sciences 33 (2010) 601–606] (which presented an alternate method of proof for the present problem), we correct the parameter regime considered in [R.A. Van Gorder, K. Vajravelu, and F. T. Akyildiz, Existence and uniqueness results for a nonlinear differential equation arising in viscous flow over a nonlinearly stretching sheet, Applied Mathematics Letters 24 (2011) 238–242] and add some details, which were omitted in the original proof. After this is done, we formulate a more elegant method of proof, converting the nonlinear ODE into a first nonlinear order system. This gives us a more natural way to view the problem and lends insight into the behavior of the solutions. Finally, we give a new way to approximate the shooting parameter α = f ′ ′ (0) analytically, through minimization of the L²([0, ∞ )) norm of residual errors. This approximation demonstrates the behavior of the parameter α we expect from the proved theorems, as well as from numerical simulations. In this way, we obtain a concise analytical approximation to the similarity solution. In summary, from this analysis, we find that monotonicity of solutions and their derivatives is essential in determining uniqueness, and these monotone solutions can be approximated analytically in a fairly simple way. Copyright © 2014 John Wiley & Sons, Ltd.     

Superatomic Boolean algebras constructed from strongly unbounded functions

Using Koszmider's strongly unbounded functions, we show the following consistency result: Suppose that κ, λ are infinite cardinals such that κ^{++ +} ≤ λ, κ^<κ = κ and 2^κ = κ⁺, and η is an ordinal with κ⁺ ≤ η < κ⁺⁺ and cf(η) = κ⁺. Then, in some cardinal‐preserving generic extension there is a superatomic Boolean algebra $\mathcal BUsing Koszmider's strongly unbounded functions, we show the following consistency result: Suppose that κ, λ are infinite cardinals such that κ^{++ +} ≤ λ, κ^<κ = κ and 2^κ = κ⁺, and η is an ordinal with κ⁺ ≤ η < κ⁺⁺ and cf(η) = κ⁺. Then, in some cardinal‐preserving generic extension there is a superatomic Boolean algebra $\mathcal B$ such that $\mathrm{ht}(\mathcal B) = \eta + 1$, $\mathrm{wd}_{\alpha }(\mathcal B) = \kappa$ for every α < η and $\mathrm{wd}_{\eta }(\mathcal B) = \lambda$(i.e., there is a locally compact scattered space with cardinal sequence 〈κ〉_η^??〈λ〉). Especially, $\langle {\omega }\rangle _{{\omega }_1}{}^{\smallfrown } \langle {\omega }_3\rangle$ and $\langle {\omega }_1\rangle _{{\omega }_2}{}^{\smallfrown } \langle {\omega }_4\rangle$ can be cardinal sequences of superatomic Boolean algebras.