Uniform exponential attractor for nonautonomous partly dissipative lattice dynamical system

In this paper,we consider the existence of a uniform exponential attractor for the nonautonomous partly dissipative lattice dynamical system with quasiperiodic external forces.     

Sequential smoothing for turning point detection with application to financial decisions

A fundamental problem in financial trading is the correct and timely identification of turning points in stock value series. This detection enables to perform profitable investment decisions, such as buying‐at‐low and selling‐at‐high. This paper evaluates the ability of sequential smoothing methods to detect turning points in financial time series. The novel idea is to select smoothing and alarm coefficients on the gain performance of the trading strategy. Application to real data shows that recursive smoothers outperform two‐sided filters at the out‐of‐sample level. Copyright © 2012 John Wiley & Sons, Ltd.     

分配格和素域生成的半环簇

Let V be the variety generated by two-element distributive lattice B2 and k prime fields Fp1,...,Fpk. That is to say that V = HSP{B2, Fp1,...,Fpk}. It is proved that the variety V is finitely based. Also, the two-element distributive lattice B2 and prime fields Fp1,..., Fpk are, up to isomorphism, the only subdirectly irreducible semirings in V. Some known results are extended and enriched.     

Compact groups of positive operators on Banach lattices

In this paper, we study groups of positive operators on Banach lattices. If a certain factorization property holds for the elements of such a group, the group has a homomorphic image in the isometric positive operators which has the same invariant ideals as the original group. If the group is compact in the strong operator topology, it equals a group of isometric positive operators conjugated by a single central lattice automorphism, provided an additional technical assumption is satisfied, for which we have only examples. We obtain a characterization of positive representations of a group with compact image in the strong operator topology, and use this for normalized symmetric Banach sequence spaces to prove an ordered version of the decomposition theorem for unitary representations of compact groups. Applications concerning spaces of continuous functions are also considered.     

基于滤波技术的首都旅游贸易发展趋势与周期研究

运用HP滤波技术,实证拟合了首都旅游贸易的发展趋势和周期.在对时间序列分离出趋势和周期之后,采用多项式拟合给出了趋势值的经验回归表达式,在此基础上,分析了剔除趋势后的贸易周期特征.研究表明,改革开放的前10年,首都旅游贸易的出口周期性表现并不明显;之后至今的20年,则呈现显著周期特征,周期长度大约5-7年,但这种周期变化也不具有稳定性.对比我国经济发展历程,首都旅游贸易出口周期与宏观经济增长周期高度一致,显示出其对宏观经济发展具有高度敏感性,因此必须重视宏观经济减速给首都旅游贸易带来的衰退影响.另外,重大事件对首都旅游贸易的影响也不容忽视.     

基于粒子滤波算法的航迹误差分析

当前针对飞行预测的研究主要采用的是kalman算法,在解决非线性问题时存在着只能近似线性的而不够精确的问题.采用近年来受到广泛关注的粒子滤波算法,针对RNAV航路进行分析,结论中得到了对飞行误差仿真分析并对比了卡尔曼滤波仿真效果,证实了粒子滤波在航迹预测中更好的准确性.     

利用MATLAB符号计算求解双正交小波滤波器系数

给出了用MATLAB符号计算求解双正交小波的滤波器系数(有理数)的程序,并更正了某些文献中的滤波器系数中的错误.     

一种高精度直流模拟量隔离传输电路的设计

在工业应用中,为了提高系统的抗干扰能力和确保系统安全可靠地运行,往往使用电量隔离技术传输信号。文章提出一种传输直流模拟量的隔离电路。此电路主要由非线性光耦、低通滤波器、脉冲发生电路及控制单元组成。它使用简化的脉冲密度调制原理,跟踪待传输的直流信号,控制脉冲波的输出,将直流信号转换成脉冲,经光耦隔离后送入滤波器还原出原信号。此电路具有体积小、成本低的特点。     

Uncomplemented subspaces of Lorentz spaces

In the paper we construct a system of bounded functions which generates an uncomplemented subspace in the Lorentz space Λ(α) for all α∈(0,1). Lower bounds of the norms of the projector onto such subspaces are obtained. Translated fromMatematicheskie Zametki, Vol. 68, No. 1, pp. 57–65, July, 2000.     

Etude de la restauration de l'aluminium irradié aux electrons (Etape III)

The nature of the electron bombarded aluminium electrical recovery process has been studied by combining quenches with irradiations. Measured Frenkel pair formation rates per incident electrons as well as annealing kinetics emphasize the role of impurity interstitial trapping.