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Science China Mathematics 2004年第1期47卷 31-38页

作者： PIAO Daxiong Department of Mathematics Ocean University of China Qingdao 266071 China

In this paper we investigate the existence and uniqueness of pseudo almost periodic solutions and unboundedness of other solutions for the systems of differential equations with piecewise constant argument [t + 1/2] by means of new notion of pseudo almost periodic vector sequences. The case in which the characteristic equation has multiple roots is considered.

关键词： pseudo almost periodic functions, pseudo almost periodic vector sequences, piecewise constant arguments, ergodic perturbation.

pseudo Asymptotically Periodic Solutions for Volterra Difference Equations of Convolution Type

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Chinese Annals of Mathematics,Series B 2019年第4期40卷 501-514页

作者： Zhinan XIA Department of Applied Mathematics Zhejiang University of Technology

In this paper, the author studies the existence and uniqueness of discrete pseudo asymptotically periodic solutions for nonlinear Volterra difference equations of convolution type, where the nonlinear perturbation is considered as Lipschitz condition or non-Lipschitz case, respectively. The results are a consequence of application of different fixed point theorems, namely, the contraction mapping principle, the Leray-Schauder alternative theorem and Matkowski’s fixed point technique.

关键词： pseudo asymptotically periodic function Volterra difference equations Contraction mapping principle Leray-Schauder alternative theorem

An explicit formula for the Webster torsion of a pseudo-hermitian manifold and its application to torsion-free hypersurfaces Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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Science China Mathematics 2006年第11期49卷 1662-1682页

作者： LUK Hing-Sun Department of Mathematics Lady Shaw Building The Chinese University of Hong KongShatinN THong KongChina

This paper gives an explicit formula for calculating the Webster pseudo torsion for a strictly pseudoconvex pseudo-hermitian hypersurface. As applications, we are able to classify some pseudo torsion-free hypersurface... 详细信息

关键词： pseudo Hermitian manifolds, torsion formula, torsion-free hypersufaces.

pseudo almost periodic solutions to parabolic boundary value inverse problems

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Science China Mathematics 2008年第7期51卷 1203-1214页

作者： ZHANG ChuanYi & YANG FengLin Department of Mathematics,Harbin Institute of Technology,Harbin 150001,China Department of Mathematics Harbin Institute of Technology Harbin China

We first define the pseudo almost periodic functions in a more general setting.Then we show the existence,uniqueness and stability of pseudo almost periodic solutions of parabolic inverse problems for a type of bounda... 详细信息

关键词： pseudo almost periodic function inverse problem parabolic equation boundary value problem

Structure analysis of a class of fuzzy controllers using pseudo trapezoid shaped membership functions

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Science China(Technological Sciences) 2000年第3期43卷 263-274页

作者：曾珂张乃尧徐文立 Automation Department Tsinghua University Beijing 100084 China

An output expression of a class of dual-input single-output fuzzy controllers using pseudo trapezoid shaped membership function is given. By structure analysis it is prdved that this class of fuzzy controllers is the sum of a global two-dimensional multi-level relay and a local linear or nonlinear proportional-integral or proportional-differential controller. And the output of this class of fuzzy controllers is a continuous, non-decreasing function of its input variables. These and other meaningful results derived from structure analysis based on the output expressions can guide the design of fuzzy controllers.

关键词： fuzzy control pseudo trapezoid shaped function structure analysis.

Rapid single flux quantum pseudo random generator

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Chinese Science Bulletin 2001年第2期46卷 170-173页

作者： Enhai Zhao Qiheng Cheng Zelu Fu Lei Liu Zhengmin Ji Wenglei Shan Yijun Feng Peiheng Wu Nanjing Univ Dept Elect Sci & Engn Nanjing 210093 Peoples R China

The principles and characteristics of rapid single flux quantum (RSFQ) circ- uits are discussed. According to these theories, we have designed RSFQ inverter, XOR cell and shift registers relative to the pseudo random generator. Based on these cells, the RSFQ pseudo random generator is given. Compared with the simulation result of another mathematical model that is established by MATLAB, the design of the RSFQ pseudo random generator is proved to be reasonable and meets our expectations.

关键词： rapid single flux quantum pseudo random generator Josephson junction superconducting quantum interferometer (SQUID).

The Production of pseudo Goldstone Boson in Top Quark Rare Decay

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Communications in Theoretical Physics 2002年第5期38卷 566-570页

作者： HUANG Jin-Shu LU Gong-Ru Department of Physics Henan Nanyang Normal College Nanyang 473061 China Department of Physics Henan Normal University Xinxiang 453002 China

We calculate the flavor changing t → cπ0 decay in the framework of the topcolor assisted multiscaletechnicolor model. We find that (a) the branching ratio of t → cπ0 is insensitive to mπ, mπs and mπt, while it increasesquickly as ε increases; (b) for reasonable ranges of the parameters, the maximum of the branching ratio in this modelmay reach 7 × 10-6, seven orders larger compared to the one t → cH0 calculated in the standard model. This mightprovide an opportunity to detect the rare decay of the top quark in experiments.

关键词： branching ratio, rare decay of the top quark, pseudo Goldstone boson, technicolor

Prescribed performance neural control to guarantee tracking quality for near space kinetic kill vehicle

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Journal of Systems Engineering and Electronics 2019年第3期30卷 573-586页

作者： ZHANG Tao LI Jiong LI Weimin WANG Huaji LEI Humin Air and Missile Defense College Air Force Engineering University

A prescribed performance neural controller to guarantee tracking quality is addressed for the near space kinetic kill vehicle (NSKKV) to meet the state constraints caused by side window detection. Different from the traditional prescribed performance control in which the shape of the performance function is constant, this paper exploits new performance functions which can change the shape of their function according to different symbols of initial errors and can ensure the error convergence with a small overshoot. The neural backstepping control and the minimal learning parameters (MLP) technology are employed for exploring a prescribed performance controller (PPC) that provides robust tracking attitude reference trajectories. The highlight is that the transient performance of tracking errors is satisfactory and the computational load of neural approximation is low. The pseudo rate (PSR) modulator is used to shape the continuous control command to pulse or on-off signals to meet the requirements of the thruster. Numerical simulations show that the proposed method can achieve state constraints, pseudo-linear operation and high accuracy.

关键词： prescribed performance control near space kinetic kill vehicle (NSKKV) neural approximation minimal learning parameter (MLP) pseudo rate (PSR) modulator

pseudo πIONIZATION POTENTIALS OF H-(CH_2)_n-X

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Chinese Chemical Letters 1991年第10期2卷 783-784页

作者： Yi WANG and Li LI (Department of Chemistry, Peking University, Beijing, 100871)

By means of the energy level formula E(p)=α+2βcos(pπ/(n+t+1)). the pseudo π ionization potentials of H-(CH_2)_n-X (X=H, F, Cl, Br, I, OH, and SH) are identified by optimizing linear regression analysis, from which... 详细信息

关键词： CH2 IONIZATION POTENTIALS OF H pseudo n-X

Current practices and future prospects for the management of gallbladder polyps: A topical review

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World Journal of Gastroenterology 2018年第26期24卷 2844-2852页

作者： R Stephen McCain Anna Diamond Claire Jones Helen G Coleman Centre for Public Health Institute of Clinical Sciences Queens University Belfast Ulster Hospital South Eastern Health and Social Care Trust Mater Hospital Belfast Health and Social Care Trust Queens University Belfast Centre for Public Health Queen’s University Belfast

A gallbladder polyp is an elevation of the gallbladder mucosa that protrudes into the gallbladder lumen. Gallbladder polyps have an estimated prevalence in adults of between 0.3%-12.3%. However, only 5% of polyps are considered to be "true" gallbladder polyps, meaning that they are malignant or have malignant potential. The main radiological modality used for diagnosing and surveilling gallbladder polyps is transabdominal ultrasonography. However, evidence shows that other modalities such as endoscopic ultrasound may improve diagnostic accuracy. These are discussed in turn during the course of this review. Current guidelines recommend cholecystectomy for gallbladder polyps sized 10 mm and greater, although this threshold is lowered when other risk factors are identified. The evidence behind this practice is relatively low quality. This review identifies current gaps in the available evidence and highlights the necessity for further research to enable better decision making regarding which patients should undergo cholecystectomy, and/or radiological follow-up.

关键词： Gallbladder polyps Gallbladder cancer True polyps pseudo polyps