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5G technology requirements and related test environments for evaluation

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China Communications 2016年第S2期13卷 42-51页

作者： xi Meng jian Li Dong zhou Dacheng Yang Beijing University of Posts and Telecommunications ZTE Corporation

To meet the considerably increase of mobile data traffic and wireless communication connections around 2020,the 5th generation(5G)mobile network will necessarily consider more frequency bands,enabling technologies and diversified key performance indicators and test environments comparing with existing network,for example Long Term *** specifically,the obvious difference between 5G and previous wireless communication system are not only included eMBB(enhance mobile broadband) usage scenario,but also introduced mMTC(massive machine type communications)and URLLC(ultra-reliable and low latency communications) usage ***,in order to evaluate 5G related technologies,some novel test environments will be widely discussed,as well as,certain new key performance indicators will be drawn into5 G evaluation methodology for satisfied new *** will discuss characteristic of these 4 candidate test environments,such as indoor isolated environment,high speed train environment;and the definition of 15 keys performance indicator will be explained and clarified,for example,Throughput,Network Energy Efficiency,Device Connection Density and so ***,high-level assessment method of each test environment also will be initially *** is notable that an initial evaluation of indoor isolated environment also can be found,which the results show that there are 3 times average cell spectral efficiency than IMT-advanced's in same test environment.

关键词： 5G IMT-2020 test environment requirements key performance indicators

A comprehensive comparison of different regression techniques and nature-inspired optimization algorithms to predict carbonation depth of recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 30-50页

作者： Bin xi Ning ZHANG Enming LI Jiabin LI jian zhou Pablo SEGARRA Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Universidad Politécnica de Madrid-ETSI Minas y Energía Madrid 28003Spain Department of Civil Engineering KU Leuven CampusBrugge 8200Belgium School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The utilization of recycled aggregates(RA)for concrete production has the potential to offer substantial environmental and economic ***,RA concrete is plagued with considerable durability concerns,particularly *** advance the application of RA concrete,the establishment of a reliable model for predicting the carbonation is *** the one hand,concrete carbonation is a long and slow process and thus consumes a lot of time and energy to *** the other hand,carbonation is influenced by many factors and is hard to *** this,this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth(CD)of RA *** types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive *** was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer(XGB-MVO)with R^(2) value of 0.9949 and 0.9398 for training and testing sets,***-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were *** also showed better generalization capabilities when compared with different models in the ***,this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

关键词： recycled aggregate concrete carbonation depth nature-inspired optimization algorithms extreme gradient boosting technique parametric analysis

紫草素和胡桃醌对舌癌Tca8113细胞的增殖抑制及凋亡诱导作用比较研究

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中国实用口腔科杂志 2017年第9期10卷 550-553页

作者：马阿西叶周建业施文郑雪莉西北民族大学口腔医学院甘肃兰州730030 兰州大学口腔医学院甘肃兰州730000

目的比较紫草素和胡桃醌对舌癌Tca8113细胞的增殖抑制及凋亡诱导作用。方法采用MTT法观察紫草素和胡桃醌对Tca8113细胞的增殖抑制作用并绘制细胞生长曲线;采用Hoechst 33258染色法检测两种药物对Tca8113细胞的凋亡诱导作用;采用SPSS19.... 详细信息

目的比较紫草素和胡桃醌对舌癌Tca8113细胞的增殖抑制及凋亡诱导作用。方法采用MTT法观察紫草素和胡桃醌对Tca8113细胞的增殖抑制作用并绘制细胞生长曲线;采用Hoechst 33258染色法检测两种药物对Tca8113细胞的凋亡诱导作用;采用SPSS19.0软件包对数据进行单因素方差分析及t检验。结果5~25μmol/L浓度范围内,两种药物对Tca8113细胞的生长抑制作用呈现出明显的剂量和时间依赖性,且两种药物均可诱导Tca8113细胞凋亡;15μmol/L紫草素的增殖抑制作用及诱导凋亡作用均强于胡桃醌(P<0.05)。结论紫草素对Tca8113细胞的增殖抑制作用及凋亡诱导作用强于胡桃醌。

关键词：紫草素胡桃醌舌癌Tea8113细胞增殖抑制凋亡诱导

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI jian zhou Gao-Liang YAN Zheng-xin LIU Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

Synthesis of Methyl-substituted Phthalazinone-based Aromatic Poly(amide imide)s

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Chinese Chemical Letters 2002年第9期13卷 824-825页

作者： xiu Ling ZHU xi Gao jian Lian zhou CHEN Department of Polymer Science&Materials Dalian University of TechnologyDalian 116012

A series of novel aromatic poly ( amide imide)s containing phthalazinone moieties were prepared from 2-(4-aminophenyl)-4-[3-methyl-4-(4-aminophenoxy)-2,3-phthalazinone-1], a novel diamine 1 with four diimide-dicarboxylic acids by Yamazaki phosphorylation method with the inherent viscosity of 0.36~0.65 dL/g. These polymers had high glass transition temperatures above 300C and they lost 10% weight between 426~475C in N2. The structure of diamine 1 and the polymers was confirmed by IR, 1H NMR and MS. The obtained polymers were readily soluble in polar solvents such as NMP, m-cresol etc. and easily cast into tough, flexible films. The X-ray indicated that they are all amorphous.

关键词： Aromatic poly(amide imide) phthalazinone synthesis heat-resistance.

A coordinated consistency voltage stability control method of active distribution grid

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Journal of Modern Power Systems and Clean Energy 2018年第1期6卷 85-94页

作者： xi YE jian LE Yongyan LIU Wu zhou Kaipei LIU College of Electrical Engineering Wuhan University

The presence of distributed generators(DGs)with high penetration poses new challenges in the management and operation of electrical *** to the local character of DGs,they could in principle be used in emergency situations to prevent a voltage instability event of the *** this paper,a certain method is proposed to coordinate the operation of virtual power plant(VPP)and conventional voltage regulation device to improve the static voltage stability of distribution network with the multi-agent *** concept and the general framework of this coordinated control system is introduced,and the voltage instable nodes are determined based on the voltage instability *** voltage coordinated control model of the distribution system is established according to the multi-agent consistency control theory and the coordinated controllers for agents are designed by solving a problem with bilinear matrix inequality *** suggested method is implemented on an IEEE 33 nodes test system and the simulation results show its efficiency and validity.

关键词： Virtual power plant Distributed generation Coordinated consistency control Static voltage stability

A Cost-Efficient Approach to Storing Users'Data for Online Social Networks

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Journal of Computer Science & Technology 2019年第1期34卷 234-252页

作者： Jing-Ya zhou jian-xi Fan Cheng-Kuan Lin Bao-Lei Cheng School of Computer Science and Technology Soochow UniversitySuzhou 215006China Provzncial Key Laboratory for Computer Information Processing Technology Soochow UniversitySuzhou 215006China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing University Nanjing 210023China

As users increasingly befriend others and interact online via their social media accounts,online social networks (OSNs)are expanding *** with the big data generated by users,it is imperative that data storage be distributed,scalable,and *** one of the most significant challenges about this topic is determining how to minimize the cost without deteriorating system *** many storage systems use the distributed key value store,it cannot be directly applied to OSN storage *** because users'data are highly correlated,hash storage leads to frequent inter-server communications,and the high inter-server traffic costs decrease the OSN storage system's scalability. Previous studies proposed conducting network partitioning and data replication based on social ***,data replication increases storage costs and impacts traffic ***,we consider how to minimize costs from the perspective of data storage,by combining partitioning and *** cost-efficient data storage approach supports scalable OSN storage *** proposed approach co-locates frequently interactive users together by conducting partitioning and replication simultaneously while meeting load-balancing *** experiments are undertaken on two real- world traces,and the results show that our approach achieves lower cost compared with state-of-the-art *** we conclude that our approach enables economic and scalable OSN data storage.

关键词： online social network inter-server traffic cost storage cost network partitioning data replication

Assembly and packing models of [Ti_(6)Co_(12)] ring based on the titanium-capped cobalt clathrochelates

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Chinese Chemical Letters 2021年第2期32卷 923-925页

作者： Hao Fu Shuyu zhou xi Fan Lei Zhang jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter.Chinese Academy of SciencesFuzhou 350002China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

In this work,titanium-capped cobalt clathrochelates have been applied as secondary building units(SBUs) fo r the construction of supramolecular *** heterometallic wheel-like [Ti_(6) Co_(12)] complexes based on cobalt clathrochelates,[C_(6)H_(15)N_(4)]_(2)[TiCo_(2)(μ_(2)-Oipr)(Oipr)_(2)(Dmg)_(3)]_(6)(2,Dmg=dimethy[glyoxime) and H_(6)[TiCo_(2)(μ_(2)-Oipr)(Oipr)_(2)(Dmg)_(3)]_(6)(3),have been successfully synthesized and *** supramolecular stacking modes of these wheels are largely dependent on the applied synthetic conditions,which further impact their gas adsorption properties.

关键词： Titanium-oxo clusters Wheel-like molecule Coordination self-assembly Heterometallic complexes Clathrochelates

Orientation and strain rate dependent tensile behavior of single crystal titanium nanowires by molecular dynamics simulations

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Journal of Materials Science & Technology 2018年第5期34卷 864-877页

作者： Le Chang Chang-Yu zhou Hong-xi Liu jian Li xiao-Hua He School of Mechanical and Power Engineering Nanjing Tech University Nanjing 211816 China School of Mechanical Engineering Jiangsu University of Science and Technology Zhenjiang 212000 China

Molecular dynamics simulation was employed to study the tensile behavior of single crystal titanium nanowires（NWs）with[112^-0],[1^-100] and[0001]orientations at different strain rates from 10^8s^-1 to 10^11s^-*** strain rates are above 10^10s^-1,the state transformation from HCP structure to amorphous state leads to super plasticity of Ti NWs,which is similar to FCC *** strain rates are below 10^10s^-1,deformation mechanisms of Ti NWs show strong dependence on *** [112^-0] orientated NW.{101^-1} compression twins（CTs）and the frequently activated transformation between CTs and deformation faults lead to higher plasticity than the other two orientated ***,tensile deformation process along [112^-0] orientation is insensitive to strain *** [1^-100] orientated NW,prismaticslip is the main deformation mode at 10^8s^-*** the strain rate increases,more types of dislocations are activated during plastic deformation ***[0001]orientated NW,{101^-2} extension twinning is the main deformation mechanism,inducing the yield stress of [0001] orientated NW,which has the highest strain rate *** number of initial nucleated twins increases while the saturation twin volume fraction decreases nonlinearly with increasing strain rate.

关键词： Molecular dynamics Single crystal titanium nanowires Strain rate Orientation Plastic deformation mechanisms