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Energy efficiency optimization for HCNs based on small base station transmission power allocation

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 19-25页

作者： pan ziyu Hu Han Department of Information and Communication Engineering Nanjing Institute of TechnologyNanjing 211167China Jiangsu Provincial Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

In the research of green communication,considering the base station(BS)power allocation from the perspective of energy efficiency(EE)is meaningful for heterogeneous cellular networks(HCNs)optimization.The EE of two-tier HCNs was analyzed and a new method for the network EE optimization was proposed by adjusting the small BS transmitting power.First,the HCNs ware modeled by homogeneous Poisson point processes(PPPs),and the coverage probability of BSs in each tier was derived.Second,according to the definition of EE,and the closed-form of EE was given by deriving the total power consumption and total throughput of HCNs respectively.At last,the analytical performance of the EE of HCNs on the small BS transmission power was analyzed,and a small BS power optimization algorithm was proposed to maximize the EE.Simulation results show that,the transmission power of small BS has a significant impact on the EE of HCNs.Furthermore,by optimizing the transmission power of small BS,the EE of HCNs can be improved effectively.

关键词： heterogeneous cellular networks EE small BS transmission power

Coverage Probability and Average Rate of Uplink Cellular Networks Based on a 3-D Model

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Chinese Journal of Electronics 2018年第5期27卷 1098-1103页

作者： pan ziyu ZHU Qi LIANG Guangjun HU Han The Key Wireless Lab of Jiangsu Province School of Telecommunication and Information EngineeringNanjing University of Posts and Telecommunications School of Communications Engineering Nanjing Institute of Technology

Uplink cellular networks are usually modeled using simple Wyner-type cellular models where interference is simplified as a single random variable, or via 2-D Poisson point process(PPP) theory, with mobile users either scattered randomly or placed deterministically. These models are insufficient to evaluate performance in dense urban environments where a large number of small cells are installed. We take a fresh look at this problem using tools from 3-D PPP, and we develop a new general model based on 3-D space for uplink cellular networks. The main idea is modeling mobile users and small cells as two separate spatial PPPs. Under general assumptions, the uplink coverage probability can be easily evaluated through fast integral calculation. We compare our model to the traditional 2-D model and actual mobile user/small cell deployment, and we observe that the proposed model is more accurate and provides a closer bound of coverage probability.

关键词： Uplink cellular networks Coverage probability Poisson point process 3-D space

Optimal UAV deployment in downlink non-orthogonal multiple access system:a two-user case

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High Technology Letters 2020年第4期26卷 411-416页

作者：刘婷婷 Wang Yuntian Wang Junhua pan ziyu Yu Yu School of Information and Communication Engineering Nanjing Institute of TechnologyNanjing 211167P.R.China Nanjing University of Science and Technology Nanjing 210094P.R.China Nanjing University of Aeronautics and Astronautics Nanjing 210024P.R.China

This paper investigates a unmanned aerial vehicle(UAV)deployment problem in a non-orthogonal multiple access(NOMA)system,where the UAV is deployed as an aerial mobile base station to transmit data to two ground users.An optimization problem is formulated by deploying the UAV for maximizing the sum rate of the two users.In order to solve the optimization problem,the feasible solution region is first reduced to a line segment between two users.Then,the optimization problem is simplified to a univariate problem,which can be solved by derivation under a certain situation,and the corresponding analytical solution is also provided.Moreover,a generalized algorithm,which considers 2 situations,is proposed to further determine the optimal UAV’s location.Specifically,four cases are discussed in the first situation.Extensive simulations are depicted to demonstrate effectiveness of the proposed algorithm and its superiority over the benchmarks in maximizing the two users’sum rate.

关键词： unmanned aerial vehicle(UAV)deployment downlink non-orthogonal multiple access(NOMA) two-user case

Uplink user allocation scheme in cognitive coexistent cellular network

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High Technology Letters 2014年第4期20卷 376-382页

作者：刘婷婷 Wang Mao Shu Feng Wang Jianxin pan ziyu School of Communication Engineering Nanjing Institute of Technology School of Electronic Engineering and Optoelectronic Techniques Nanjing University of Science and Technology

In order to address spectrum resource scarcity in traditional cellular networks,television(TV)white space is considered as a potential solution to offload a portion of network traffic and enlarge network capacity.This paper describes a cognitive cellular network which allocates low geometry users to the TV white space based on a proportional fair criterion.An uplink user allocation scheme is proposed and the validity of the proposed scheme is established by simulation of the cellular network usage in conjunction with the TV white space.The simulation results show clear improvements in both the user and the system performance with the cognitive coexistent cellular network compared with the traditional cellular network,and that the performance of the proposed user allocation scheme is superior to other user allocation schemes.

关键词：蜂窝网络分配方案上行链路用户共存网络使用情况仿真结果资源稀缺

High precision patternable liquid metal based conductor and adhesive substrate enabled stretchable hybrid systems

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Nano Research 2024年第6期17卷 5595-5603页

作者： Runhui Zhou Jiaoya Huang Zemin Li Yushu Wang ziyu Chen Caofeng pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Institute of Atomic Manufacturing Beihang UniversityBeijing 100191China

Stretchable hybrid systems have been attracting tremendous attention for their essential role in soft robotics,on-skin electronics,and implantable devices.Both rigid and soft functional modules are typically required in those devices.Consequently,ensuring stable electrical contact between rigid and soft modules is a vital part.Here,we propose a simple,universal,and scalable strategy for the stretchable hybrid system through a highly precise printable liquid metal particle-based conductor and adhesive fluorine rubber substrate.The properties of liquid metal particle-based conductors could be easily tuned to realize high-precision patterning,large-scale printing,and the ability to print on various substrates.Additionally,the fluorine rubber substrate could form strong interfacial adhesion with various components and materials through simply pressing and heating,hence enabling stable electrical contact.Furthermore,we prepared a stretchable hybrid light-emitting diode(LED)display system and employed it in on-skin visualization of pressure levels,which perfectly combined rigid and soft modules,thus demonstrating the promising potential applications in complex multifunctional stretchable hybrid systems for emerging technologies.

关键词： stretchable hybrid systems liquid metal high precision interfacial adhesion

Covalent Organic Framework with 3D Ordered Channel and Multi-Functional Groups Endows Zn Anode with Superior Stability

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Nano-Micro Letters 2024年第4期16卷 350-363页

作者： Bin Li Pengchao Ruan Xieyu Xu Zhangxing He Xinyan Zhu Liang pan ziyu Peng Yangyang Liu Peng Zhou Bingan Lu Lei Dai Jiang Zhou School of Chemical Engineering North China University of Science and TechnologyTangshan 063009People’s Republic of China School of Materials Science and Engineering Central South UniversityChangsha 410083People’s Republic of China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China Hunan Provincial Key Defense Laboratory of High Temperature Wear‑Resisting Materials and Preparation Technology Hunan University of Science and TechnologyXiangtan 411201People’s Republic of China School of Physics and Electronics Hunan UniversityChangsha 410082People’s Republic of China

Achieving a highly robust zinc(Zn)metal anode is extremely important for improving the performance of aqueous Zn-ion batteries(AZIBs)for advancing“carbon neutrality”society,which is hampered by the uncontrollable growth of Zn dendrite and severe side reactions including hydrogen evolution reaction,corrosion,and passivation,etc.Herein,an interlayer containing fluorinated zincophilic covalent organic framework with sulfonic acid groups(COF-S-F)is developed on Zn metal(Zn@COF-S-F)as the artificial solid electrolyte interface(SEI).Sulfonic acid group(-SO_(3)H)in COF-S-F can effectively ameliorate the desolvation process of hydrated Zn ions,and the three-dimensional channel with fluoride group(-F)can provide interconnected channels for the favorable transport of Zn ions with ion-confinement effects,endowing Zn@COF-S-F with dendrite-free morphology and suppressed side reactions.Consequently,Zn@COF-S-F symmetric cell can stably cycle for 1,000 h with low average hysteresis voltage(50.5 m V)at the current density of 1.5 m A cm^(-2).Zn@COF-S-F|Mn O_(2)cell delivers the discharge specific capacity of 206.8 m Ah g^(-1)at the current density of 1.2 A g^(-1)after 800 cycles with high-capacity retention(87.9%).Enlightening,building artificial SEI on metallic Zn surface with targeted design has been proved as the effective strategy to foster the practical application of high-performance AZIBs.

关键词： Aqueous Zn ion batteries Covalent organic framework Interfacial modification Zn ion flux regulation Desolvation effect

Regulating interfacial behavior of zinc metal anode via metal-organic framework functionalized separator

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Journal of Energy Chemistry 2024年第6期93卷 213-220,I0006页

作者： Ruotong Li Liang pan ziyu Peng Ningning Zhao Zekun Zhang Jing Zhu Lei Dai Ling Wang Zhangxing He School of Chemical Engineering North China University of Science and TechnologyTangshan 063210HebeiChina

Aqueous zinc ion batteries(AZIBs)are one of the promising energy storage devices.However,uncontrolled dendrite and side reactions have seriously hindered its further application.In this study,the metal-organic framework(MOF)functionalized glass fiber separator(GF-PFC-31)was used to regulate interfacial behavior of zinc metal anode,enabling the development of high-performance AZIBs.In PFC-31,there areπ-πinteractions between two adjacent benzene rings with a spacing of 3.199 A.This spacing can block the passage of[Zn(H_(2)O)_6]^(2+)(8.6 A in diameter)through the GF-PFC-31 separator to a certain extent,which promotes the deposition process of Zn ions.In addition,the sulfonic acid group(-S03H)contained in GF-PFC-31 can form a hydrogen bonding network with H_(2)O,which can provide a desolvation effect and reduce the side reaction.Consequently,GF-PFC-31 separator achieves uniform deposition of Zn ions.The Zn‖GF-PFC-31‖Zn symmetric cell exhibits stable cycle life(3000 h at 1.2 mA cm^(-2),2000 h at 0.3 mA cm^(-2),and 2000 h at 5.0 mA cm^(-2)),and Zn‖GF-PFC-31‖MnO_(2) full cell with GF-PFC-31 separator can cycle for 1000 cycles at 1.2 A g^(-1)with capacity retention rate of 82.5%.This work provides a promising method to achieve high-performance AZIBs.

关键词： Aqueous zinc ion batteries Interfacial behavior Metal-organic framework Sulfonic acid group Separator

Uplink Performance Analysis in Multi-Tier Heterogeneous Cellular Networks with Power Control and Biased User Association

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China Communications 2016年第12期13卷 25-36页

作者： Han Hu Hong Wang Qi Zhu ziyu pan Jiangsu Key Lab of Wireless Communications Key Lab on Wideband Wireless Communications and Sensor Network Technology of Ministry of EducationNanjing University of Posts and Telecommunications

A K-tier uplink heterogeneous cellular network is modelled and analysed by accounting for both truncated channel inversion power control and biased user association. Each user has a maximum transmit power constraint and transmits data when it has sufficient transmit power to perform channel inversion. With biased user association, each user is associated with a base station(BS) that provides the maximum received power weighted by a bias factor, but not their nearest BS. Stochastic geometry is used to evaluate the performances of the proposed system model in terms of the outage probability and ergodic rate for each tier as functions of the biased and power control parameters. Simulations validate our analytical derivations. Numerical results show that there exists a trade-off introduced by the power cut-off threshold and the maximum user transmit power constraint. When the maximum user transmit power becomes a binding constraint, the overall performance is independent of BS densities. In addition, we have shown that it is beneficial for the outage and rate performances by optimizing different network parameters such as the power cut-off threshold as well as the biased factors.

关键词： Heterogeneous cellular network uplink performance biased user association stochastic geometry

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银纳米材料的可控合成及其环境应用

化学进展 2023年第8期35卷 1229-1257页

作者：潘自宇冀豪栋北京大学深圳研究生院环境与能源学院深圳518055

银纳米材料因催化活性高、生物相容性好、物化性能独特而备受关注,已被广泛应用于催化、药物、环境等领域。本文首先介绍了银纳米材料的种类、性质及合成策略,重点对可控合成方法进行了归纳总结,并讨论了机器学习在银纳米材料合成中的... 详细信息

银纳米材料因催化活性高、生物相容性好、物化性能独特而备受关注,已被广泛应用于催化、药物、环境等领域。本文首先介绍了银纳米材料的种类、性质及合成策略,重点对可控合成方法进行了归纳总结,并讨论了机器学习在银纳米材料合成中的新成果。然后综述了近年来银纳米材料在环境中的应用,如污染物去除、杀菌和病毒灭活、传感器等。基于此,本文主要就银纳米材料的种类、可控合成及其环境应用进行综述和展望。

关键词：银纳米材料种类可控合成环境应用