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Modular handover algorithm for 5G HetNets with comprehensive load index

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The Journal of China Universities of Posts and Telecommunications 2017年第2期24卷 57-65页

作者： Li Danyang zhang zhizhong Gao Yiyi Chongqing Key Laboratory of Communication Networks and Testing Technology Chongqing University of Posts and Telecommunications

Most existing handover decision system （HDS） designs are monolithic, resulting in high computational cost and unbalance of overall network. A novel modular handover algorithm with a comprehensive load index for the 5th generation （5G） heterogeneous networks （HetNets） is proposed. In this paper, the handover parameters, serving as the basis for handover, are classified into network＇s quality of service （QoS） module, user preference （UP） module and degree of satisfaction （DS） module according to the new modular HDS design. To optimize switching process, the comprehensive network load index is deduced by using triangle module fusion operator. With respect to the existing handover algorithm, the simulation results indicate that the proposed algorithm can reduce the handover frequency and maintain user satisfaction at a higher level. Meanwhile, due to its block calculation, it can bring about 1.4 s execution time improvement.

关键词： 5G HetNets handover modular HDS comprehensive load index

An Improved Convolutional Neural Network Based Indoor Localization by Using Jenks Natural Breaks Algorithm

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China Communications 2022年第4期19卷 291-301页

作者： Chengjie Hou Yaqin Xie zhizhong zhang School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqingChina School of Electronic and Information Engineering Nanjing University of Information Science and TechnologyNanjingChina

With the rapid growth of the demand for indoor location-based services(LBS), Wi-Fi received signal strength(RSS) fingerprints database has attracted significant attention because it is easy to obtain. The fingerprints algorithm based on convolution neural network(CNN) is often used to improve indoor localization accuracy. However, the number of reference points used for position estimation has significant effects on the positioning accuracy. Meanwhile, it is always selected arbitraily without any guiding standards. As a result, a novel location estimation method based on Jenks natural breaks algorithm(JNBA), which can adaptively choose more reasonable reference points, is proposed in this paper. The output of CNN is processed by JNBA, which can select the number of reference points according to different environments. Then, the location is estimated by weighted K-nearest neighbors(WKNN). Experimental results show that the proposed method has higher positioning accuracy without sacrificing more time cost than the existing indoor localization methods based on CNN.

关键词： indoor localization convolution neural network(CNN) Wi-Fi fingerprints Jenks natural breaks

Caching modeling and energy analyzing of cell-free wireless heterogeneous networks with beta Ginibre point process

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Digital Communications and Networks 2023年第4期9卷 931-940页

作者： Linlin Feng zhizhong zhang Haonan Hu Errong Pei School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065P.R.China School of Electronic and Information Engineering Nanjing University of Information Science and TechnologyNanjing210044P.R.China

Cell-free Wireless Heterogeneous Networks(HetNets)have emerged as a technological alternative for conventional cellular *** this paper,we study the spatially correlative caching strategy,the energy analysis,and the impact of parameter β on the total energy cost of the cell-free wireless HetNets with Access Points distributed by Beta Ginibre Point Process(β-GPP).We derive the approximate expression of Successful Delivery Probability(SDP)based on the Signal-to-Interference-plus-Noise Ratio coverage *** both analytical and simulation results,it is shown that the proposed caching model based on β-GPP placement,which jointly takes into account path loss,fading,and interference,can closely simulate the caching performance of the cell-free HetNets in terms of *** guaranteeing the outage probability constraints,the analytical expression of the uplink energy cost is also *** conclusion is that with AP locations modeled by β-GPP,the power consumption is not sensitive to β,but is sensitive to the dimension of the kernel function;hence β is less restrictive,and only the truncation of the Ginibre kernel has to be appropriately *** findings are new compared with the existing literature where the nodes are commonly assumed to be of Poisson Point Process,Matern Hard-Core Process,or Poisson Cluster Process deployment in cell-free systems.

关键词： Caching model Energy analysis Cell-free HetNets β-GPP

Numerical simulation of metal evaporation based on the kinetic model equation and the direct simulation Monte Carlo method

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Chinese Physics B 2018年第12期27卷 361-367页

作者： Xiaoyong Lu Xiaozhang zhang1 zhizhong zhang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Research Institute of Physics and Chemical Engineering of Nuclear Industry Tianjin 300180China

Metal evaporation on the basis of the kinetic model equations(BGK and S-model) and the direct simulation Monte Carlo(DSMC) method was investigated computationally under the circumstances of collimators existing or not. Numerical data of distributions of number density, bulk velocity and temperature were reported over a wide range of evaporation *** was shown that these results reached a good agreement for the case of small evaporation rate, while the deviations became increasingly obvious with the increase of evaporation rate, especially when the collimators existed. Moreover, the deposition thickness over substrate obtained from the kinetic model equations were inaccurate even though the evaporation rate was small. All of the comparisons showed the reliability of the kinetic model equations, which require less computational cost at small evaporation rate and simple structure.

关键词： kinetic model equations DSMC metal evaporation collimators

From borophosphate to fluoroborophosphate:a rational design of fluorine-induced birefringence enhancement

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Science China Chemistry 2021年第9期64卷 1498-1503页

作者： Wenyao zhang zhizhong zhang Wenqi Jin Ruonan zhang Meng Cheng Zhihua Yang Shilie Pan CAS Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics&ChemistryCASXinjiang Key Laboratory of Electronic Information Materials and DevicesUrumqi830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic ***,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_(2)BP_(3)O_(11)with the monoclinic space group P2_(1/c) has been synthesized in the sealed ***_(2)BP_(3)O_(11)exhibits a rare P-O-P bridge formation,which is the first example in alkaline-earth metal *** further substituting[BO_(4)]^(3-)with[BO_(3)F]^(4-),the first alkaline-earth metal/lead fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)with the same space group were *** the scissors effect of fluorine,in M_(2)BP_(2)O_(8)F(M=Ba and Pb),a BO_(3)F tetrahedron corner-sharing with three PO_(4)tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_(n)(M=Ba/Pb,n=5,6,8)distorted *** first principles calculation shows that the borophosphate Ba_(2)BP_(3)O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)have the values of 0.035 and 0.043@1,064 nm,*** an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and *** introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials.

关键词： borophosphate fluoroborophosphates P-O-P bridges formation birefringence

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Inter-operator radio interface based synchronization

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The Journal of China Universities of Posts and Telecommunications 2015年第1期22卷 31-41页

作者： Feng Linlin zhang zhizhong Hu Haonan Cheng Fang Chongqing Key Laboratory of Communication Networks and Testing Technology Chongqing University of Posts and Telecommunications

The fourth generation （4G） wireless communication systems have been deployed or are soon to be deployed in many countries. However, with an .explosion of wireless mobile devices and services, there ~are still some challenges that cannot be accommodated even by the 4G, such as the spectrum crisis and inter-cell interference. Telecom operators have turned to commit themselves to share available resources, including hardware and software resources. Therefore, with the mutual infrastructure, the ＇integration＇ should be highlighted, especially in the fifth generation （5G） wireless systems that are expected to be deployed beyond 2020. The authors in the article proposed a potential cellular architecture, and discussed the inter-operator radio interface based synchronization （RIBS） for the 5G wireless communication systems. A scheme of inter-operator RIBS and typical scenarios, along with the analysis of the corresponding interference were given. Analysis of the shared parameters, signaling coordination of inter-operator RIBS and listening reference signal （RS） design for RIBS were also carried out.

关键词： radio interface based synchronization inter-operator fifth generation wireless systems interference listening reference signal

Actual implementation of spectrum-sharing systems in rayleigh fading channels~

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High Technology Letters 2012年第2期18卷 145-150页

作者：裴二荣 Wang Sheng zhang zhizhong School of Communication and Information Engineering University of Electronic Science and Technology of ChinaChengdu611731P.R.China School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065P.R.China.

In actual implementation of spectrum sharing systems, due to the selfishness of primary users, primary users often refuse the access of secondary users to their licensed spectrum bands even if the access of secondary users doesn＇t affect their transmission. Aimed at the selfishness problem of primary users, a seller＇s market trading mechanism is introduced which can not only stimulate primary users to tolerate larger interference power but also give the primary users an appropriate compensation at the same time, and which has very important practical significance. Based on the mechanism, the achievable maximal gross profit of secondary users and their optimal power allocation scheme in the Rayleigh fading environment are derived, and the interference price of primary users and the average revenue of secondary users＇ impact on them are also studied. Numerical calculation results are conducted to verify our theoretical results.

关键词： cognitive radio spectrum sharing power allocation seller's market trading mechanism convexoptimization

Spatial Modeling and Reliability Analyzing of Reconfigurable Intelligent Surfaces-Assisted Fog-RAN with Repulsion

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China Communications 2023年第12期20卷 142-155页

作者： Linlin Feng zhizhong zhang Haonan Hu Errong Pei Yun Li School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic and Information Engineering Nanjing University of Information Science and TechnologyNanjing 210044China

Reconfigurable Intelligent Surface(RIS),fog computing,and Cell-Free(CF)network architecture are three promising technologies for application to the Ultra-Reliable Low Latency Communication(URLLC)scenario in 6G mobile communication *** paper considers a RIS-assisted FogRadio Access Network(Fog-RAN)architecture where a)the repulsively distributed Fog-Access Points(FAPs)communicate in a CF manner to suppress intercell interference,b)RISs are introduced into the CF network to avoid shadowing and enhance the system performance,and c)fog computing evolved as cloud services providers at the edge of the network and an enabler for constructing a multi-layer computing power ***,we derive and validate the integral form of the maximum F-AP offloading probability and Successful Delivery Probability(SDP)of this RIS-assisted Fog-RAN over composite FisherSnedecor F fading,where the spatial effects are reconsidered with the assumption that the F-APs are modelled as a Beta Ginibre Point Process(β-GPP).The numeric and simulation results indicate that for the investigated RIS-assisted Fog-RAN,theβ-GPP-based deployment of F-APs can increase maximum of 8%of the SDP within the repulsion-effective range,compared with the Matern Cluster Process(MCP)-based ***,deploying more RISs per F-AP offers more significant SDP improvements.

关键词： β-GPP Fog-RAN reliability analysis RIS

Caffeic acid 3,4-dihydroxyphenethyl ester prevents colorectal cancer through inhibition of multiple cancer-promoting signal pathways in 1,2-Dimethylhydrazine/dextran sodium sulphate mouse model

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Journal of Traditional Chinese Medicine 2024年第1期44卷 70-77页

作者： JIN Tao ZHOU Qian SHEN Jichen zhang zhizhong LIAN Xiaoyuan College of Pharmaceutical Sciences Zhejiang UniversityHangzhou 310058China Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Ocean College Zhoushan Campus of Zhejiang UniversityZhoushan 316021China

OBJECTIVE:To elucidate the potential feature and mechanism of the caffeic acid 3,4-dihydroxyphenethyl ester(CADPE)molecule,which can prevent colorectal cancer(CRC)in the 1,2-Dimethylhydrazine(DMH)/dextran sodium sulphate(DSS)-induced mouse ***:Institute of cancer research(ICR)male mice were injected with 20 mg/kg DMH for a *** that,2%DSS was administered in the drinking water for another 7 *** CADPE treatment was given to the DMH/DSS induced male mice at three different periods until their *** examination was used for observing the CRC development at colonic ***(IHC),blood cells smearing and crypt damage scoring methods were used for investigating the anti-inflammation feature of CADPE related to *** reversing targets searching method was applied with artificial intelligence(AI),computeraided drug designing(CADD)and Ingenuity Pathway Analysis(IPA)techniques for predicting the potential targets and mechanism of CADPE highly related to ***:The data indicated that CADPE inhibited CRC tumor development in the colitis-associated DMH/DSS induced mouse model after giving the early *** also impeded the acute inflammation by decreasing the infiltration of neutrophils significantly during the initial stage of CRC ***,our data showed that CADPE prevented CRC by blocking active sites of three pivotal protein targets including epidermal growth factor receptor(EGFR),extracellular signal-regulated kinase(ERK)and mammalian target of rapamycin(m TOR)in two major cancer development ***:CADPE effectively prevented CRC at early stage of tumor germination in the DMH/DSS mouse model highly likely due to its anti-acute inflammation characteristic and the ability of blocking EGFR,ERK and m TOR activities in two highly related CRC developing pathways.

关键词： caffeic acids colorectal neoplasms inflammation chemoprevention Sarcandra glabra