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Science Letters:A simplified MMSE-based iterative receiver for MIMO systems

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2009年第10期10卷 1389-1394页

作者： Yuan YANG Hai-lin ZHANG State Key lab of lntegrated Services Networks Xidian University Xi 'an 710071 China Datang Linktech Infosystem Co. Ltd Beijing 100191 China

A simplified minimum mean square error(MMSE) detector is proposed for joint detection and decoding of multi-ple-input multiple-output(MIMO) *** matrix inversion lemma and the singular value decomposition(SVD) of the channel matrix are used to simplify the computation of the coefficient of the MMSE *** to the original MMSE detector,the proposed detector has a much lower computational complexity with only a marginal performance *** proposed detector can also be applied to MIMO systems with high order modulations.

关键词： MIMO系统最小均方误差接收机奇异值分解计算复杂度迭代基础科学

Oscillating multidromion excitations in higher-dimensional nonlinear lattice with intersite and external on-site potentials using symbolic computation

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Chinese Physics B 2014年第1期23卷 98-107页

作者： B. Srividya L. Kavitha R. Ravichandran D. Gopi Department of Physics Periyar University Salem 636 011 India Department of Physics K.S.R. College of Engineering Tiruchengode 637 215 India Centre for Nanoscience and Nanotechnology Periyar University Salem 636 011 India Department of Chemistry Periyar University Salem 636 011 India

We show by an extensive method of quasi-discrete multiple-scale approximation that nonlinear multi-dimensional lattice waves subjected to intersite and external on-site potentials are found to be governed by （N＋ 1 ）-dimensional nonlinear Schr6dinger （NLS） equation. In particular, the resonant mode interaction of （2＋l）-dimensional NLS equation has been identified and the theory allows the inclusion of transverse effect. We apply the exponential function method to the （2＋ I ）- dimensional NLS equation and obtain the class of soliton solutions with a purely algebraic computational method. Notably, we discuss in detail the effects of the external on-site potentials on the explicit form of the soliton solution generated recursively. Under the action of the external on-site potentials, the model presents a rich variety of oscillating multidromion patterns propagating in the system.

关键词： solitons partial differential equations lattice dynamics exact solutions

Computing the Determinant of a Matrix with Polynomial Entries by Approximation

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Journal of Systems Science & Complexity 2018年第2期31卷 508-526页

作者： QIN Xiaolin SUN Zhi LENG Tuo FENG Yong Department of Mathematics Sichuan University Chengdu 610064 China Chengdu Institute of Computer Applications Chinese Academy of Sciences Chengdu 610041 China Chengdu Institute of Computer Applications Chinese Academy of Sciences Chengdu 610041 China. School of Computer engineering and Science Shanghai University Shanghai 200444 China.

与 univariate 和 multivariate 多项式条目计算一个矩阵的决定因素在地的科学计算并且设计经常产生。这份报纸建议一个有效算法用混合符号、数字的计算与多项式条目计算一个矩阵的决定因素。算法为解决 Vandermonde 系统与错误控制依... 详细信息

与 univariate 和 multivariate 多项式条目计算一个矩阵的决定因素在地的科学计算并且设计经常产生。这份报纸建议一个有效算法用混合符号、数字的计算与多项式条目计算一个矩阵的决定因素。算法为解决 Vandermonde 系统与错误控制依靠牛顿插值方法。作者也介绍度矩阵为尺寸减小与多项式条目，和度同形方法在一个矩阵估计变量的度。而且，方法的并行化自然地产生。

关键词：多项式矩阵计算条目有效算法插值方法错误控制并行化

Higher-Order WHEP Solutions of Quadratic Nonlinear Stochastic Oscillatory Equation

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engineering（科研） 2013年第5期5卷 57-69页

作者： Mohamed A. El-Beltagy Amnah S. Al-Johani Department of Applied Mathematics College of Science Northern Borders University Arar KSA College of Home Economics Northern Borders University Arar KSA Department of engineering Mathematics & Physics Engineering Faculty Cairo University Giza Egypt

This paper introduces higher-order solutions of the quadratic nonlinear stochastic oscillatory equation. Solutions with different orders and different number of corrections are obtained with the WHEP technique which uses the WienerHermite expansion and perturbation technique. The equivalent deterministic equations are derived for each order and correction. The solution ensemble average and variance are estimated and compared for different orders, different number of corrections and different strengths of the nonlinearity. The solutions are simulated using symbolic computation software such as Mathematica. The comparisons between different orders and different number of corrections show the importance of higher-order and higher corrected WHEP solutions for the nonlinear stochastic differential equations.

关键词： Oscillatory Equation Nonlinear Differential Equations Stochastic Differential Equation Wiener-Hermite Expansion Perturbation Technique

A Method to Obtain Complex Transfer Functions of Four Order DC-DC Converters

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Journal of Energy and Power engineering 2016年第10期10卷 615-622页

作者： Josep M. Vails Marti Pedro M. Gil Izco Department of Electrical and Electronic engineering Public University of Navarra (UPNA) Campus of Arrosadla-Pamplona Navarra 31006 Spain

Boundary Control of PDEs and Applications to Turbulent Flows and Flexible Structures

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Boundary Control of PDEs and Applications to Turbulent Flows...

Performance comparison and parametric study on spiral groove gas film face seals

第25届中国控制会议

作者： Miroslav Krstic Andrey Smyshlyaev Rafael Vazquez Department of Mechanical and Aerospace engineering University of California at San Diego La JollaCA 92093-0411 USA Department of Mechanical and Aerospace engineering University of California at San Diego La JollaCA 92093-0411 USA Department of Mechanical and Aerospace engineering University of California at San Diego La JollaCA 92093-0411 USA

＜正＞We present a tutorial overview of new methods for designing feedback controllers for infinite-dimensional systems controlled from the boundary. Such problems arise in turbulent flow control, chemical process control, fusion, nanotechnology applications such as control of cantilever beams in atomic force microscopes, etc. Due to the inherent high dimensionality and unbounded input and output operators, control methods that mimic standard finite-dimensional techniques and require the solution of operator Riccati equations are hard to apply to these problems. We present a set of novel controller and observer design techniques inspired by geometric nonlinear control tools and "backstepping", which employ only symbolic computation. In flow control applications these techniques can be employed in such a way that not only the turbulence is suppressed but the linearized Navier-Stokes PDEs are solved explicitly. In control of flexible beams the new techniques remove the need for collocated actuators and sensors, which has permeated this field for decades. For distributed parameter systems with unknown parameters we show adaptive control techniques that ensure stabilization even in the most challenging of cases like the cases with infinite relative degrees, infinitely many unknown parameters, and infinitely many unmeasured states. Trajectory tracking problems are rarely, if ever, pursued for PDE systems. We show that they become readily tractable with the new techniques. All of the new techniques are fully accessible to researchers with an engineer’s level of mathematical background. This area is just transitioning from its infancy period to the period where numerous open problems exist and have come within reach. It presents excellent opportunities to young researchers looking for topics with both theoretical and applied impact.

关键词： distributed parameter systems adaptive control flow control Navier-Stokes equations

来源： cnki会议评论

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Science China(Physics,Mechanics & Astronomy) 2004年第Z1期47卷 29-36页

作者： LIU Yuchuan, SHEN Xinmin, XU Wanfu & WANG ZhiliState Key laboratory of Tribology, Tsinghua University, Beijing 100084, China School of Mechanical engineering and Automation, Beijing University of Aeronautics and Astronautics, Beijing 100083, China Lubrication Technology Research Center, Shenyang Institute of Technology, Shenyang 110015, China Tsing Hua Univ State Key Lab Tribol Beijing 100084 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100083 Peoples R China Shenyang Inst Technol Lubricat Technol Res Ctr Shenyang 110015 Peoples R China

Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In the computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.

关键词： spiral groove, gas film face seals, parameter study, performance comparison, finite element method.

Localized characteristics of lump and interaction solutions to two extended Jimbo–Miwa equations

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Chinese Physics B 2020年第12期29卷 174-180页

作者：尹宇航陈思佳吕兴 Department of Mathematics Beijing Jiaotong UniversityBeijing 100044China Beijing laboratory of National Economic Security Early-warning engineering Beijing Jiaotong UniversityBeijing 100044China

We focus on the localized characteristics of lump and interaction solutions to two extended Jimbo–Miwa *** on the Hirota bilinear method and the test function method,we construct the exact solutions to the extended equations including lump solutions,lump–kink solutions,and two other types of interaction solutions,by solving the underdetermined nonlinear system of algebraic equations for associated ***,analysis and graphical simulation are presented to show the dynamical characteristics of our solutions and the interaction behaviors are revealed.

关键词： Hirota bilinear method test function method lump solution interaction solution symbolic computation

Nucleon-pair approximation with uncoupled representation

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Chinese Physics C 2021年第5期45卷 129-140页

作者：雷杨路毅赵玉民 School of National Defense Science and Technology Southwest University of Science and TechnologyMianyang 621010China College of Physics and engineering Qufu Normal UniversityQufu 273165China Shanghai Key laboratory of Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we propose an approach to nucleon-pair approximation(NPA)with m-scheme bases,in which the collective nucleon pairs are represented in terms of antisymmetric matrices,and commutations between nucleon pairs are given using a matrix multiplication that avoids angular-momentum couplings and *** the present approach significantly simplifies the NPA ***,it is formulated on the same footing with and without isospin.

关键词： uncoupled representation nucleon-pair approximation formalism computational efficiency