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Adaptive bit allocation scheme in multi-cell cooperative block diagonalization systems with delayed and limited feedback

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The Journal of China Universities of Posts and Telecommunications 2012年第5期19卷 9-15,25页

作者： gui Xin KANG gui-xia Huang Dong-yan LIUjia ZHANG ping Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Beijing 100876 China

In multi-cell cooperative multi-input multi-output （MIMO） systems, base station （BS） can exchange and utilize channel state information （CSI） of adjacent cell users to manage co-channel interference. Users quantize the CSIs of desired channel and interference channels using finite-rate feedback links, then BS can generate cooperative block diagonalization （BD） precoding matrices using the obtained quantized CSI at transmitter to supress co-channel interference. In this paper, a novel adaptive bit allocation scheme is proposed to minimize the rate loss due to imperfect CSI. We derive the closed-form expression of rate loss caused by both channel delay and limited feedback. Based on the derived rate loss expression, the proposed scheme can adaptively allocate more bits to quantize the better channels with smaller delays and fewer bits to worse channels with larger delays. Simulation results show that the proposed scheme yields higher performance than other allocation schemes.

关键词： block diagonalization multi-cell cooperative MIMO system adaptive bit allocation scheme channel delay and limited feedback

Effect of 2s Orbitals on the Electronic Hopping in Polyacetylene

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Chinese Physics Letters 1997年第1期14卷 59-62页

作者： TONG guo-ping Department of Physics Zhejiang Normal UniversityJinhua 321004

The extended Wannier function constructed by hydrogen-like atom wave function is used to calculate the electronic hopping and the density of the states of trans-polyacetylene with a single-chain planar *** this technique 2s and 2pz orbitals are taken into *** computed result shows that the electronic hopping interactions,especially non-neighbor hopping,are considerably affected by 2s orbitals,which are able not only to narrow the energy bandwidth and the gap but also to weaken the nearest neighbor hopping slightly and to enhance the non-neighbor hopping greatly.

关键词： structure. neighbor narrow

A three-dimensional inverse method based on moving no-slip boundary for profiled end wall design

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Chinese Journal of Aeronautics 2024年第10期37卷 221-233页

作者： Hanwen guo Donghai JIN Jiancheng ZHANG Xingmin gui School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Nanchang 330096China

How to utilize existing flow control mechanisms to make profiled end wall design more flexible,efficient,and physical is a meaningful *** study presents a three-dimensional inverse method for profiled end wall design to achieve the application of flow control *** predetermined pressure distribution on the end wall is reached by modifying the end wall geometry during flow field calculation.A motion velocity model is derived from the normal momentum equation of the moving no-slip boundary to modify the end wall geometry.A Reynolds-Averaged Navier-Stokes(RANS)solver based on the Semi-Implicit Method for Pressure Linked Equations(SIMPLE)algorithm is adopted to simulate the flow *** on the mechanism understanding obtained through numerical optimization results,this study adopts the inverse method to redesign an optimized end wall in a compressor *** results indicate that the redesigned end wall exhibits better loss reduction,reducing the overall total pressure loss by 5.5%,whereas the optimized end wall reduces it by 3%.The inverse method allows the imposition of desired influences on the end wall flow without constructing a database,making it highly flexible,efficient,and physical.

关键词： Compressor Flow control Corner separation Profiled end wall Inverse method

Attitude and Orbit Optimal Control of Combined Spacecraft via a Fully-Actuated System Approach

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Journal of Systems Science & Complexity 2022年第2期35卷 623-640页

作者： DUAN Guangquan LIU guo-ping Center for Control Theory and guidance Technology Harbin Institute of TechnologyHarbin 150001China Department of Electronic and Electrical Engineering Southern University of Science and TechnologyShenzhen 518055China

This paper investigates the attitude and orbit control for the combined spacecraft formed after a target spacecraft without the autonomous control ability is captured by a service *** optimal controller of fully-actuated system is proposed to realize the attitude and orbit stabilization control of combined *** stability of the system is proved by introducing Lyapunov *** simulation of the combined spacecraft and physical experiment based on the combined spacecraft simulator(CSS)are *** simulation and experiment results demonstrate the effectiveness and practicability of the optimal controller of fully-actuated system.

关键词： Attitude control combined spacecraft fully-actuated system optimal controller orbit control

Finite-Time Observability of Probabilistic Logical Control Systems

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Journal of Systems Science & Complexity 2023年第5期36卷 1905-1926页

作者： ZHOU Rongpei guo Yuqian LIU Xinzhi gui Weihua School of Information Engineering Nanchang UniversityNanchang 330031China School of Automation Central South UniversityChangsha 410083China Department of Applied Mathematics University of WaterlooWaterlooOntarioN 2L 3G 1Canada

This study investigates finite-time observability of probabilistic logical control systems(PLCSs)under three definitions(i.e.,finite-time observability with probability one,finite-time singleinput sequence observability with probability one,and finite-time arbitrary-input observability with probability one).The authors adopt a parallel extension technique to recast the finite-time observability problem of a PLCS as a finite-time set reachability ***,the finite-time set reachability problem can be transferred to stabilization problem of a logic dynamical system by using the state transfer graph reconstruction *** and sufficient conditions for finite-time observability under the three definitions are derived ***,the proposed methods are illustrated by numerical examples.

关键词： Finite-time observability finite-time set reachability probabilistic logical control systems semi-tensor products

Sex differences in the association between the muscle quality index and the incidence of depression: A cross-sectional study

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World Journal of Psychiatry 2024年第9期14卷 1335-1345页

作者： gui-ping Huang Li-ping Mai Zhi-Jie Zheng Xi-Pei Wang guo-Dong He Institute of Medical Research Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Depression presents significant challenges to mental health *** phy-sical activity is highly beneficial to mental and physical health,relatively few stu-dies have conducted on the relationship between *** To investigate the association between muscle quality index(MQI)and incidence of *** The data used in this cross-sectional study were obtained from the 2011-2014 National Health and Nutritional Examination Survey,which included informa-tion on MQI,depression,and confounding *** logistic regre-ssion models were employed,while taking into account the complex multi-stage sampling design.A restricted cubic spline model was utilized to investigate the non-linear relationship between the MQI and ***,subgroup analyses were performed to identify influential *** The prevalence of depression in this population was 8.44%.With the adjusted model,the MQI was associated with depression in females(odds ratio=0.68,95%confidence interval:0.49-0.95)but not in males(odds ratio=1.08,95%confidence interval:0.77-1.52).Restricted cubic spline adjustment of all covariates showed a significant negative non-linear relationship between depression and the MQI in *** observed trend indicated an 80%decrease in the risk of depression for each unit increase in MQI,until a value of ***,when the MQI exceeded 2.2,the prevalence of depression increased by 20%for every unit increase in the *** analyses further confirmed that the MQI was negatively associated with *** The MQI was inversely correlated with depression in females but not males,suggesting that females with a higher MQI might decrease the risk of depression.

关键词： Sex differences Muscle quality index Depression National Health and Nutrition Examination Survey Population-based study

Deterministic Quantum Key Distribution Using Two Non-orthogonal Entangled States

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Communications in Theoretical Physics 2007年第3期47卷 459-463页

作者： guo Ying ZENG gui-Hua Department of Communication Engineering Central South University Changsha 410083 China Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200030 China

A deterministic quantum key distribution scheme using two non-orthogonal entangled states is proposed. In the proposed scheme, communicators share key information by exchanging one travelling photon with two random and secret polarization angles. The security of the distributed key is guaranteed by three checking phases in three-way channel and the communicators＇ secret polarization angles.

关键词： quantum key distribution quantum entanglement state

Stabilization of Boolean control networks with state-triggered impulses

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Science China(Information Sciences) 2022年第3期65卷 123-137页

作者： Rongpei ZHOU Yuqian guo Xinzhi LIU Weihua gui School of Automation Central South University Department of Applied Mathematics University of Waterloo

Previously, impulses were used to model abrupt changes in dynamic biological systems. This paper introduces a hybrid-index model that can characterize instantaneity of the impulsive behavior more effectively, compared with the existing impulsive Boolean network models. Using the hybrid-index model,we investigate the set stabilization of Boolean control networks with state-triggered impulses in the hybriddomain and the time-domain. We establish necessary and sufficient conditions for set stabilizability in the hybrid and time domains, using the methods of k-domain and quotient mapping, respectively. Further, we obtain algorithms for constructing all hybrid-optimal and time-optimal set stabilizers by partitioning the state space into layers. The relationships between different set stabilizabilities are summarized. In addition,we have shared two examples to demonstrate the main results.

关键词： Boolean control networks set stabilization state-triggered impulses hybrid-index model semi-tensor product of matrices

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Non-recurrence of exp(z)/z

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Acta Mathematica Sinica,English Series 2013年第4期29卷 703-716页

作者： guo ping ZHAN School of Mathematics and Computational Science Sun Yat-sen University Department of Mathematics Nanjing University

Abstract In this paper, we consider the dynamics of the map z →＊ exp（z）/z on the punctured plane C＊ = C／{0}. We show that for almost every point z∈C＊, the w-limit set of z is equal to {0, ∞}. In particular, t... 详细信息

关键词： Non-recurrence w-limit set Julia set nesting condition