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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

A non-stationary channel model for 5G massive MIMO systems

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Frontiers of Information Technology & Electronic Engineering 2017年第12期18卷 2101-2110页

作者： Jian-qiao CHEN Zhi ZHANG Tian TANG yu-zhen huang Department of Information and Communication Engineering Beijing University of Posts and Telecommunications Beifing 100876 China

We propose a novel channel model for massive multiple-input multiple-out （MIMO） communication systems that incorporate the spherical wave-front assumption and non-stationary properties of clusters on both the array and time axes. Because of the large dimension of the antenna array in massive MIMO systems, the spherical wave-front is assumed to characterize near-field effects resulting in angle of arrival （AoA） shifts and Doppler frequency variations on the antenna array. Additionally, a novel visibility region method is proposed to capture the non-stationary properties of clusters at the receiver side. Combined with the birth-death process, a novel cluster evolution algorithm is proposed. The impacts of cluster evolution and the spherical wave-front assumption on the statistical properties of the channel model are investigated. Meanwhile, corresponding to the theoretical model, a simulation model with a finite number of rays that capture channel characteristics as accurately as possible is proposed. Finally, numerical analysis shows that our proposed non-stationary channel model is effective in capturing the characteristics of a massive MIMO channel.

关键词： Massive MIMO Spherical wave-front assumption Non-stationary property Birth-death process Visibility region method

A projected gradient based game theoretic approach for multi-user power control in cognitive radio network

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Frontiers of Information Technology & Electronic Engineering 2018年第3期19卷 367-378页

作者： yun-zheng TAO Chun-yan WU yu-zhen huang Ping ZHANG State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications College of Communications Engineering PLA University of Science and Technology

The fifth generation （5G） networks have been envisioned to support the explosive growth of data demand caused by the increasing traditional high-rate mobile users and the expected rise of interconnections between human and things. To accommodate the ever-growing data traffic with scarce spectrum resources, cognitive radio （CR） is considered a promising technology to improve spectrum utilization. We study the power control problem for secondary users in an underlay CR network. Unlike most existing studies which simplify the problem by considering only a single primary user or channel, we investigate a more realistic scenario where multiple primary users share multiple channels with secondary users. We formulate the power control problem as a non-cooperative game with coupled constraints, where the Pareto optimality and achievable total throughput can be obtained by a Nash equilibrium （NE） solution. To achieve NE of the game, we first propose a projected gradient based dynamic model whose equilibrium points are equivalent to the NE of the original game, and then derive a centralized algorithm to solve the problem. Simulation results show that the convergence and effectiveness of our proposed solution, emphasizing the proposed algorithm, are competitive. Moreover, we demonstrate the robustness of our proposed solution as the network size increases.

关键词： Cognitive radio networks Multi-user power control Non-cooperative game Nash equilibrium Projected gradient

Development of limestone calcined clay cement concrete in South China and its bond behavior with steel reinforcement

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第11期21卷 892-907页

作者： zhen-yu huang You-shuo huang Wen-yu LIAO Ning-xu HAN Ying-wu ZHOU Feng XING Tong-bo SUI Bin WANG Hong-yan MA Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen 518060China Department of Civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65401USA Si noma Research Institute Si noma International Engineering Co.Ltd.Beijing 100102China

Limestone calcined clay cement(LC^3),consisting of ordinary Portland cement(OPC)clinker,calcined clay,limestone powder,and gypsum,has been considered a promising solution to current challenges in the cement and concrete industry,such as high carbon emissions,high energy consumption,and resource *** study carries out a series of experimental investigations of LC^3-based paste,mortar,and concrete,including microstructural analyses(*** product characterization and pore structure analysis)and macro-scale testing(*** and mechanical properties),using raw materials from south *** results show that,in LC^3 paste,the replacement of clinker by calcined clay and limestone leads to an increased volume of small pores but decreased total volume of *** workability of LC^3 mortar and concrete can be readily tailored using conventional *** designed for comparable 28-d compressive strength,the LC^3 mortar and concrete tend to have lower early-age compressive strength,but comparable compressive strength and higher flexural strength than those of the OPC counterparts at late *** study also examines the bond-slip behavior between LC^3 concrete and steel bars and finds that the bond strength is comparable to that of OPC concrete with the same 28-d compressive strength,but that the LC^3 concrete-rebar interface exhibits higher bond-slip *** findings on LC^3 concrete provide fundamental information and guidance for furthering the application of LC^3 binder in structural concrete in the near future.

关键词： Limestone calcined clay cement(LC^3) Hydration Bond-slip Mercury intrusion porosimetry(MIP) Scanning electron microscope(SEM) Bond strength

MECHANISM ON ENERGY TRANSMISSION CONTROL IN BEAMS BASED ON A PIEZOELECTRIC TRANSDUCER

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MECHANISM ON ENERGY TRANSMISSION CONTROL IN BEAMS BASED ON A...

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

2012全国压电和声波理论及器件技术研讨会

作者： Tian-zhu XU zhen-yu huang Hai-li LIU Department of Instrument Science and Engineering Shanghai Jiao Tong University

In a beam-like structure,which acts as a vibration transmission path,transmitted energy can be effectively suppressed by employing an active *** energy transmission control can also be achieved at a certain frequency band without external energy by attaching a mechanical system,which may be composed with piezoelectric transducers,on the beam.A mass-spring attachment is modeled to investigate the relationship between the mechanical impedance and the working ***,the relationship between the working bandwidth and circuit parameters of the piezoelectric transducer is developed to show the feasibility of adjusting the working bandwidth.A case study of a passive system called as dog-bone structure was carried out to show that control range can be expanded by changing the dimension of the *** addition,the piezoelectric constant and capacity also determine the control performance.

关键词： Energy transmission Piezoelectric transducer Vibration control Wave theory

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang yuefeng Yan zhen Wang Guansheng Ma Dechang Jia Xiaoxiao huang yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu Jing Wu Guang Yin Fan‑zhen Jiao Zhong‑zhen yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

Effect of ozonated water on normal vaginal microecology and Lactobacillus

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Chinese Medical Journal 2019年第9期132卷 1125-1127页

作者： Qiong-Qiong Zhang Lei Zhang Ying Liu Ying Wang Rui Chen zhen-yu huang Tao Lyu Qin-Ping Liao School of Clinical Medicine Tsinghua UniversityBeijing 100084China Department of Obstetrics and Gynecology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

To the Editor:The female vagina is a complex microecology ***,the vaginal microbiota of healthy women is dominated by H2O2-producing Lactobacillus,which decomposes glycogen in vaginal epithelial cells into lactic acid... 详细信息

关键词： Editor vagina cells

Studies on the synthesis and bioactivities of new isosteviol derivatives

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Studies on the synthesis and bioactivities of new isosteviol...

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

2011年全国药物化学学术会议——药物的源头创新

作者： LU Li-Hui,yu zhen-Lei,ZHANG huang-huang,TAO,Jing-Chao~* Department of Chemistry,New Drug Research and Development Center,zhengzhou University, zhengzhou 450052

＜正＞In recent years,isosteviol derivatives have attracted scientific attention because of their remarkably broad spectrum of biological activities including anti-hypertension, anti-inflammatory,anti-tumor and *** hy...

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang yu-Wen Alvin huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB