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Joint cooperative beamforming and artificial noise design for secure AF relay networks with energy-harvesting eavesdroppers

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Frontiers of Information Technology & Electronic Engineering 2017年第6期18卷 850-862页

作者： He-hao NIU Bang-ning ZHANG Dao-xing GUO yu-zhen huang Ming-yue LU College of Communications Engineering PLA University of Science and TechnologyNanjing 210007China

In this paper, we investigate physical layer security for simultaneous wireless information and power transfer in amplify-and-forward relay networks. We propose a joint robust cooperative beamforming and artificial noise scheme for secure communication and efficient wireless energy transfer. Specifically, by treating the energy receiver as a potential eavesdropper and assuming that only imperfect channel state information can be obtained, we formulate an optimization problem to maximize the worst-case secrecy rate between the source and the legitimate information receiver under both the power constraint at the relays and the wireless power harvest constraint at the energy receiver. Since such a problem is non-convex and hard to tackle, we propose a two-level optimization approach which involves a one-dimensional search and semidefinite relaxation. Simulation results show that the proposed robust scheme achieves better worst-case secrecy rate performance than other schemes.

关键词： Simultaneous wireless information and power transfer Physical layer security Relay networks Cooperative beamforming Artificial noise

EFFECTS OF LIQUID COMPRESSIBILITY ON RADIAL OSCILLATIONS OF GAS BUBBLES IN LIQUIDS

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Journal of Hydrodynamics 2012年第5期24卷 760-766页

作者： ZHANG yu-ning LI Sheng-cai School of Engineering University of Warwick Coventry UK CV4 7AL

For forced radial oscillations of gas bubbles in liquids, a more rigorous expression of the acoustic damping constant based on Keller＇s equation is developed. Comparison with those in published papers is also made. The expression offered in this paper will improve the predictions of total damping constant in particular for high frequencies and large bubbles, i.e., large ωR0 / c1 （ ω is the frequency of driving sound field, Ro is the equilibrium bubble radius, c1 is the sound speed in the liquid）. Examples in ultrasound imaging and acoustical oceanography are demonstrated.

关键词： gas bubble damping constant liquid compressibility natural frequency

Demonstration of Inverse Scattering Transform for DNLS Equation

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Communications in Theoretical Physics 2007年第2X期48卷 299-303页

作者： YANG Chun-Nuan yu Jia-Lu WANG Qu-Quan huang Nian-ning Department of Physics Wuhan University Wuhan 430072 China

Since the Jost solutions of the DNLS equation does not tend to the free Jost solutioins as ｜λ｜→∞, the usual inverse scattering transform （IST） must be revised. Beside the Kaup and Newell＇s approach, we propose a simple revision in constructing the equations of IST, where the usual Zakharov-Shabat kern is revised by multiplying λ^-2 or λ^-1. To justify the revision we show that the Jost solutions obtained do satisfy the pair of compatibility equations.

关键词： inverse scattering transform soliton solutions Liouville theorem

Multi-Robot Cooperative Localization:Time-Varying Unobservable Subspace Analysis and Consistent Algorithm Design

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Journal of Systems Science & Complexity 2024年第5期37卷 1937-1955页

作者： HAO ning HE Fenghua YAO yu School of Astronautics Harbin Institute of TechnologyHarbin 150000China

This paper investigates the problem of cooperative localization(CL)for a multi-robot system(MRS)under dynamic measurement topology,which involves a group of robots collectively estimating their poses with respect to a common reference frame using ego-motion measurements and robot-to-robot relative *** authors provide a theoretical analysis of the time-varying unobservable subspace and propose a consistent cooperative localization ***,the authors introduce the relative measurement graph(RMG)to represent the relative pose measurements obtained by the MRS at each ***,the authors derive the local observability matrix over a time *** equivalent relationship is established between the local observability matrix and the spectral matrices of the ***,the authors present a method for constructing the unobservable subspace based on the RMG under different topology *** on this analysis,the authors design a consistent cooperative localization algorithm that satisfies the constraints of the time-varying unobservable *** analytical optimal solution is derived for the constrained optimization *** Carlo numerical simulations are conducted to demonstrate the consistency and accuracy of the proposed method.

关键词： Consistency cooperative localization multi-robot system null space relative measurement graph time-varying unobservable subspace

A state-of-the-art review on low-frequency nonlinear vibration isolation with electromagnetic mechanisms

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Applied Mathematics and Mechanics(English Edition) 2022年第7期43卷 1045-1062页

作者： Bo YAN ning yu Chuanyu WU School of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China

Vibration isolation is one of the most efficient approaches to protecting host structures from harmful vibrations,especially in aerospace,mechanical,and architectural engineering,*** linear vibration isolation is hard to meet the requirements of the loading capacity and isolation band simultaneously,which limits further engineering application,especially in the low-frequency *** recent twenty years,the nonlinear vibration isolation technology has been widely investigated to broaden the vibration isolation band by exploiting beneficial *** of the most widely studied objects is the"three-spring"configured quasi-zero-stiffness(QZS)vibration isolator,which can realize the negative stiffness and high-static-low-dynamic stiffness(HSLDS)*** nonlinear vibration isolation with QZS can overcome the drawbacks of the linear one to achieve a better broadband vibration isolation *** to the characteristics of fast response,strong stroke,nonlinearities,easy control,and low-cost,the nonlinear vibration with electromagnetic mechanisms has attracted *** this review,we focus on the basic theory,design methodology,nonlinear damping mechanism,and active control of electromagnetic QZS vibration ***,we provide perspectives for further studies with electromagnetic devices to realize high-efficiency vibration isolation.

关键词： quasi-zero-stiffness(QZS) nonlinear vibration isolation low-frequency electromagnetic vibration isolation bistable

De-noising of radiation pressure signal generated by bubble oscillation based on ensemble empirical mode decomposition

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Journal of Hydrodynamics 2022年第5期34卷 849-863页

作者： Xiang-hao Zheng yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The radiation pressure signals generated by the bubble oscillation are often utilized to recognize the characteristics of the target objects in many ***,these signals are easily contaminated by complex background *** order to accurately extract the effective components of the radiation pressure signal generated by the bubble oscillation,this paper proposes a de-noising procedure for the radiation pressure signal,based on the ensemble empirical mode decomposition(EEMD),the autocorrelation function and the modified wavelet soft-threshold de-noising *** order to verify the effectiveness of the procedure,the typical radiation pressure signal generated based on the Keller-Miksis model under the acoustic excitation is employed for the subsequent de-noising *** results of the qualitative analysis show that the amplitude and the period of the bubble oscillation can be clearly observed in the time-domain diagram of the de-noised signal based on the *** the quantitative analysis,the de-noised signal based on the EEMD has better performance with higher signal-to-noise ratio(SNR),smaller root-mean-square error,and larger correlation coefficient than that based on the wavelet transform(WT)and the empirical mode decomposition(EMD).Furthermore,with the increase of the complexity of the radiation pressure signal(e.g.,the increase of the dimensionless pressure amplitude of the acoustic wave and the decrease of the SNR of the input signal),the above three evaluation indexes of the de-noised signal based on the EEMD are all better than those based on the other two *** the signal is more complex,the de-noising capabilities of the WT,the EMD are greatly reduced,but the EEMD can still maintain the good de-noising capability,which shows the superiority of the signal de-noising procedure proposed in the present paper.

关键词： Radiation pressure cavitation bubble oscillation signal de-noising ensemble empirical mode decomposition(EEMD) autocorrelation function wavelet soft-threshold de-noising

Unmanned aerial vehicles towards future Industrial Internet:Roles and opportunities

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Digital Communications and Networks 2024年第4期10卷 873-883页

作者： Linpei Li Chunlei Sun Jiahao Huo yu Su Lei Sun Yao huang ning Wang Haijun Zhang School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China China Mobile Chengdu Institute of Research and Development Chengdu 610200China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China Chengdu University of Information Technology Chengdu 610225China Zhengzhou University Zhengzhou 450001China

Unmanned Aerial Vehicles(UAVs)are gaining increasing attention in many fields,such as military,logistics,and hazardous site *** UAVs to assist communications is one of the promising applications and research *** future Industrial Internet places higher demands on communication *** easy deployment,dynamic mobility,and low cost of UAVs make them a viable tool for wireless communication in the Industrial ***,UAVs are considered as an integral part of Industry *** this article,three typical use cases of UAVs-assisted communications in Industrial Internet are first ***,the state-of-the-art technologies for drone-assisted communication in support of the Industrial Internet are *** to the current research,it can be assumed that UAV-assisted communication can support the future Industrial Internet to a certain ***,the potential research directions and open challenges in UAV-assisted communications in the upcoming future Industrial Internet are discussed.

关键词： Unmanned aerial vehicles(UAVs) UAV-assisted communications Industrial Internet

Dietary supplementation with pyrroloquinoline quinone promotes growth,relieves weaning stress,and regulates metabolism of piglets compared with adding zinc oxide

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Animal Nutrition 2023年第4期15卷 409-419页

作者： Chenyu Shi Zirou yu Zijie Wang Ran ning Caiyun huang Youjun Gao Fenglai Wang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China College of Animal Science Fujian Agriculture and Forestry UniversityFuzhou 350002China Changmao Biochemical Engineering Company Changzhou 213000China

Hindered growth often occurs because of psychological and environmental stress during the weaning period of *** study aimed to compare the effects of growth performance,diarrhea indices,digestibility of nutrients,antioxidant capacity,neurotransmitters levels and metabolism of weaned pigs fed diets supplemented with pyrroloquinoline quinone(PQQ)and zinc oxide(ZnO).Pigs weaned at d 28(n=108)were fed with three different diets including:the basal diet(CTRL group),the basal diet supplemented with 3.0 mg/kg PQQ(PQQ group)and the basal diet containing 1,600 mg/kg ZnO(ZNO group).During the first 14 d,weaned pigs fed the diet supplemented with PQQ and ZnO decreased feed to gain ratio and diarrhea rate(P<0.01).Compared with the CTRL group,average daily gain was increased in weaned pigs in the PQQ group from d 15 to 28(P=0.03).Compared with the CTRL group,pigs fed PQQ and ZnO supplemented diets showed improved apparent total tract digestibility(ATTD)of nutrients(P≤0.05).During the overall experimental period,the concentration of malondialdehyde was decreased in plasma of pigs in the PQQ and ZNO groups compared with the CTRL group(P<0.05).At d 28,the concentration of vasoactive intestinal peptide(VIP)and calcitonin gene-related peptide(CGRP)was lower in plasma of weaned pigs in the PQQ and ZNO groups compared with the CTRL group(P<0.05).There was no difference between the PQQ and ZNO group in growth performance,ATTD of nutrition,antioxidant capacity and neurotransmitters *** increased 3-methoxy-4-hydroxymandelate(P<0.05)compared with the CTRL *** to metabolomic analysis,erucamide,formononetin and 3-methyl-L-histidine were up-regulated in the PQQ group(P<0.05).Compared with the CTRL group,aloesin and dibutyl adipate were down-regulated in the PQQ group(P<0.05).In conclusion,similar to ZnO,PQQ improves growth performance,digestibility of nutrients,antioxidant capacity,neuromodulation and metabolism of weaned ***,like ZnO,PQQ can be effectively a

关键词： Weaned pig Pyrroloquinoline quinone Zinc oxide Growth performance Metabolomics

Dynamical signatures of the one-dimensional deconfined quantum critical point

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Chinese Physics B 2022年第5期31卷 73-82页

作者： ning Xi Rong yu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China

We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product *** scaling of the correlation functions and the dispersion of the conserved current correlations explicitly show the emergence of enhanced continuous symmetries at these *** dynamical structure factors in several different channels reveal the development of deconfined fractionalized excitations at the ***,we find an effective spin-charge separation at the DQCP between the ferromagnetic(FM)and valence bond solid(VBS)phases,and identify two continua associated with different types of fractionalized excitations at the DQCP between the X-direction and Z-direction FM *** findings not only provide direct evidence for the DQCP in one dimension but also shed light on exploring the DQCP in higher dimensions.

关键词： one-dimensional antiferromagnetism spin frustration deconfined quantum critical point spin dynamics infinite time-evolving block decimation