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Energy-efficiency-aware relay selection in distributed full duplex relay network with massive MIMO

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Science China(Information Sciences) 2017年第2期60卷 126-140页

作者： yongzhi li Cheng TAO liu liU lingwen ZHANG Institute of Broadband Wireless Mobile Communications Beijing Jiaotong University National Mobile Communications Research Laboratory Southeast University

This paper considers a distributed full duplex relay network where multiple sources simultaneously transmit their signals to multiple destinations via the cooperation of a set of relay stations(RSs). Each RS is assumed to be equipped with large antenna arrays while all sources and destinations only have a single *** assume the channels are Rician fading and the RSs use linear processing to process the signals with imperfect channel state information(CSI). We derive the closed-form expressions of the end-to-end achievable rates for the maximum-ratio combining/matched-filter(MRC/MF) and the zero-forcing(ZF) processing. These results are then used to pursue a detailed analysis of the power saving of the relay network. Then we study the energy-efficiency-aware relay selection strategy since the energy efficiency affects network lifetime in future wireless network. We propose a sub-optimal strategy with low complexity that only requires the statistical *** show that the energy efficiency of the system can be improved with optimal power allocation and our proposed strategy performs very close to the exhaustive search algorithm which is optimal.

关键词： relay network full duplex massive MIMO relay selection energy efficiency

Property of alumina to adsorb long chain normal-paraffinhydrocarbons

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Chinese Science Bulletin 1998年第2期43卷 126-128页

作者： yongzhi li Xianliang Deng Weile Yu Luoyang Petrochem Engn Corp Petr Refining Res Inst Luoyang 471023 Peoples R China Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

That alumina can strongly absorb long chain normal_paraffin hydrocarbon was found when alumina was used in the preparative group_type separation of heavy petroleum fractions. The reason for the above property of alumina may be that the normal_paraffin hydrocarbons can extend closely on the alumina surface. One molecule of long chain normal_paraffin hydrocarbon can be adsorbed by many active sites of alumina surface. The longer chain normal_paraffin hydrocarbon can be adsorbed by more active sites of alumina surface; this results in the longer chain normal_paraffin hydrocarbon has a stronger adsorption on alumina.

关键词： alumina adsorption property long chain normal-paraffin hydrocarbons.

An advanced five-unknown higher-order theory for free vibration of composite and sandwich plates

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Chinese Journal of Aeronautics 2021年第9期34卷 104-118页

作者： Zhen WU Rui MA yongzhi li Yushan XIAO Jie MEI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Accurate prediction of dynamic characteristics is quite critical to understand the strength of layered ***,the existing five-unknown higher-order theories encounter difficulties to forecast accurately the dynamic response of sandwich ***,a new five-unknown higher-order theory is developed for free vibration analysis of composite and sandwich plates,which possesses the same degree of freedom as those of other five-unknown higherorder *** developed model can meet beforehand interlaminar continuity conditions and the free-surface conditions of transverse shear *** assess capability of the proposed model,analytical solution for such composite structures with simply-supported conditions has been presented by employing Hamilton’s principle,which is utilized for analysis of mechanical behaviors of composite and sandwich *** with the three-dimensional(3 D)elasticity solutions,3 D finite element results and the results obtained from the chosen five-unknown higher-order models,the proposed model can yield accurately natural frequencies of composite and sandwich *** for the thick plates,the higher-order frequencies calculated from the proposed model are in good agreement with the 3 D finite element *** studying effect of the thickness/length ratios on natural frequencies,it is found that the proposed model is adaptable to predicting natural frequencies of the sandwich plates with the thickness/length ratios between 1/4 and 1/*** addition,some factors influencing accuracy of five-unknown higher-order models have been investigated in ***,by means of numerical analysis and discussion,some conclusions have been drawn as well,which can serve as a reference for other investigators.

关键词： Analytical solution Five-unknown Free vibrations Higher-order theory Sandwich plates

Validated,Rapid and Sensitive HPLC-MS/MS Method for Determination of 7,4'-Dihydroxylflavone in Rat Plasma and Its Application to Preliminary Pharmacokinetics

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Journal of Beijing Institute of Technology 2019年第4期28卷 731-738页

作者： Shibo Wang Panpan li yongzhi li Jiaping Wang Yujuan li School of life Science Beijing Institute of TechnologyBeijing 100081China China Astronaut Research and Training Centre Beijing 100094China

A sensitive,specific and rapid high-performance liquid chromatography-electronic spray ionization-tandem mass spectrometric method was developed and validated for the determination of 7,4'-dihydroxylflavone(7,4'-DHF)in rat ***(internal standard,IS)was added in the collected plasma samples and subsided together by a simple one-step protein precipitation using acetonitrile-methanol(1:1,v/v).Chromatographic separation was performed on an Agilent Zorbax XDB C18 chromatography column and gradient elution with the mobile phase consisting of methanol and 0.1%formic acid was *** mass spectrometric detection was performed by negative ion electro-spray ionization in multiple selected reactions monitoring(MRM)mode,with the transitions of m/z 253.1→113.0 for 7,4'-DHF and m/z 268.9→158.8 for *** calibration curve has liner relationship over the concentration range of ***/mL(r=0.995.4).The intra-and inter-day precision(RSD%)was less than 10%,and the accuracy(RE%,relative error)ranged from-5.2%to 8.0%.The fully validated method was applied to the pharmacokinetics(PK)of 7,4'-dihydroxylflavone(7,4'-DHF)in rat plasma after oral administration(two doses:15 and ***/kg)and intravenous injection(***/kg).The result showed that Tmax and Cmax was 1.33±0.29.h and 0.12±***/mL(***/kg),and 1.17±0.29.h and 0.17±***/mL(***/kg),*** bioavailability was 0.078%(***/kg)and 0.070%(***/kg),respectively.

关键词： 7,4'-dihydroxylflavone HPLC-MS/MS pharmacokinetics bioavailability

Impact of aperture on dynamic response of sandwich plates with aluminium face-sheets and PMI core based on an alternative finite element formulation and experiments

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Chinese Journal of Aeronautics 2022年第4期35卷 266-280页

作者： Zhen WU yongzhi li Dongjian ZHANG Jie MEI Xiaohui REN Rui MA School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechanical Engineering Xi an Aeronautical UniversityXi'an 710065China

Apertures generally exist in the sandwich structures attributing to mechanical connection and lightweight, which might induce failure of such structures. Thus, it is required to realize the impact of aperture on mechanical behaviors of sandwich structures. If transverse shear deformations are unable to be described accurately, the reasonable prediction of dynamic behaviors of the form-core sandwich plates with apertures will meet severe challenges due to a large difference of transverse shear modulus at the adjacent layers. Thereby, such issue is less studied by using the efficient models and experimental testing, so an alternative sinusoidal-type finite element formulation is to be proposed to precisely predict dynamic response of the form-core sandwich structures with apertures. The proposed finite element formulation can meet beforehand compatible conditions of transverse shear stresses at the interfaces of adjacent laminates. In order to appraise strictly capability of the proposed model, experimental tests on natural frequencies of three groups of specimens with different apertures have been carried out. Moreover, four specimens in each group are tested to reduce the testing errors, which is less reported in the published literature. In addition,three-dimensional Finite Element Method(3-D FEM) is also selected to account for the good performance of the present model. Finally, the impact of aperture diameter on the natural frequencies of the sandwich structures is both experimentally and numerically investigated, which can serve as a reference for other researchers.

关键词： Dynamic response Sandwich plates Higher-order theory Experimental tests Finite element method

强骨抗萎方抑制模拟失重肌管细胞萎缩机制的研究

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航天医学与医学工程 2024年第1期35卷 20-25页

作者：武睿鹏王佳平李勇枝李玉娟北京理工大学生命学院北京100081 中国航天员科研训练中心北京100094

目的探讨中药复方强骨抗萎方(QG)对模拟失重效应诱导的小鼠肌管细胞萎缩的保护效果。方法将诱导分化成功的小鼠肌管细胞(C2C12细胞)分为六组。然后通过三维回转器建立48 h小鼠肌管细胞模拟微重力效应(simulated microgravity effect,SMG... 详细信息

目的探讨中药复方强骨抗萎方(QG)对模拟失重效应诱导的小鼠肌管细胞萎缩的保护效果。方法将诱导分化成功的小鼠肌管细胞(C2C12细胞)分为六组。然后通过三维回转器建立48 h小鼠肌管细胞模拟微重力效应(simulated microgravity effect,SMG)模型(48h-SMG组),其中三组给予2.50、1.25、0.625 mg/mL的QG,一组给予2.70μg/mL阿仑膦酸钠作为阳性对照。通过H2O2、MDA检测试剂盒和TNF-αEliSA试剂盒检测肌管细胞中氧化因子和炎性因子的水平。采用蛋白质印迹法(Western blotting法)检测肌管细胞中NF-κB/IκB蛋白质分解通路和IGF-1/PI3K/Akt蛋白质合成通路的相关蛋白质表达水平,并采用7μmol/L IGF-1抑制剂处理后对IGF1/PI3K/Akt通路进行验证。结果与对照组相比,48h-SMG组的肌管氧化水平和炎性水平显著上升(P<0.05),IKK、NF-κB和MURF-1蛋白的表达水平显著上升19.9%±6.1%、189.3%±15.9%、445.0%±46.1%,IκB表达水平显著降低26.5%±0.1%(P<0.05)。IGF-1/PI3K/Akt通路中IGF-1、PI3K、p-Akt/Akt和mTOR的水平降低23.6%±0.5%、30.7%±2.7%、13.3%±1.1%、21.0%±1.6%(P<0.05)。三个剂量的QG均能降低细胞氧化应激和炎性水平(P<0.05),并激活IGF-1/PI3K/Akt通路,抑制NF-κB/IκB通路蛋白的表达,其中高剂量QG(2.50 mg/mL)使IKK、NF-κB和MURF-1蛋白的表达水平显著降低39.9%±2.4%、48.6%±0.1%、70.0%±2.1%(P<0.05),IGF-1、PI3K和mTOR的表达水平和Akt磷酸化水平显著提高43.1%±1.1%、100.0%±7.7%、71.8%±2.5%、95.2%±12.8%(P<0.05)。结论QG能够通过调控蛋白质合成和分解通路显著抑制模拟微重力效应引起的肌管细胞萎缩。

关键词：模拟失重效应强骨抗萎方 C2C12细胞肌管细胞萎缩

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约束砌体结构抗震加固研究

重庆建筑 2024年第7期23卷 65-69页

作者：李勇志许子宜陈俊驰中电建重庆勘测设计研究院有限公司重庆401329 西南交通大学土木工程学院四川成都610031

为研究约束砌体结构在采用混凝土条带、窗下墙设缝、窗间墙宽度增大等加固方法作用下的破坏模式,该文以2层开洞砌体结构为研究对象,采用数值模拟技术,建立多组试验模型,研究了条带配筋率、窗下墙设缝深度、窗间墙宽度在动力时程作用下... 详细信息

为研究约束砌体结构在采用混凝土条带、窗下墙设缝、窗间墙宽度增大等加固方法作用下的破坏模式,该文以2层开洞砌体结构为研究对象,采用数值模拟技术,建立多组试验模型,研究了条带配筋率、窗下墙设缝深度、窗间墙宽度在动力时程作用下对约束砌体结构抗震性能及自振周期的影响,并以墙体破坏率为指标,定量研究了条带配筋率、窗下墙设缝深度、窗间墙墙体宽度等单因素下的合理取值,研究表明:窗间墙宽度的合理取值应大于900 mm;混凝土条带的钢筋配筋率合理取值为大于0.65%;窗下墙设缝深度的合理取值为200 mm。

关键词：约束砌体结构抗震加固动力时程分析抗震性能

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Optimization design for polymeric S-shaped ridge waveguide

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Chinese Science Bulletin 2010年第17期55卷 1834-1839页

作者： LU RongGuo liAO JinKun TANG XiongGui li HePing liU yongzhi School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

The dispersion characteristics and transverse field distribution of the fundamental and higher order modes are analyzed for polymeric ridge multimode waveguide by a new technique which is based on the combination of the effective index method and the variational method. An algorithm is implemented to study the effect of the structure parameters and dimensions on the dispersion curves. The optical field distribution of the fundamental and higher order modes for TM modes are computed. The single mode conditions of polymeric ridge waveguide are obtained. The relationship between the curvature radius and the bending loss of S-shaped ridge waveguide are studied with wide-angle finite-difference beam propagation method and effective index method. The conclusion is: when the curvature radius is larger than 5000 μm, the bending loss will not decrease distinctly even if the curvature radius increases, and the light can propagate stably in the S-shaped ridge waveguide.

关键词：脊波导聚合物 S形优化设计有限差分光束传播法曲率半径弯曲损耗有效折射率

基于网络药理学探讨茵陈干预肝纤维化的作用机制

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湖南中医杂志 2024年第4期40卷 161-167页

作者：李勇志郑玉刘森浩唐嘉璐李超威云南中医药大学第三附属医院云南昆明650011

目的:基于网络药理学方法探讨茵陈干预肝纤维化的作用机制。方法:通过TCMSP数据库获取茵陈的活性成分及作用靶点;在GeneCards数据库和OMIM数据库中获取肝纤维化的相关靶点,将茵陈成分靶点与疾病靶点取交集,获得茵陈干预肝纤维化的作用... 详细信息

目的:基于网络药理学方法探讨茵陈干预肝纤维化的作用机制。方法:通过TCMSP数据库获取茵陈的活性成分及作用靶点;在GeneCards数据库和OMIM数据库中获取肝纤维化的相关靶点,将茵陈成分靶点与疾病靶点取交集,获得茵陈干预肝纤维化的作用靶点。运用Cytoscape 3.10.0构建化合物-靶点-疾病网络图,使用STRING数据库获得蛋白质-蛋白质相互作用(PPI)网络,通过Cytoscape 3.10.0进行可视化呈现及分析。使用Metascape数据库进行基因本体(GO)功能和京都基因与基因组百科全书(KEGG)通路富集分析。结果:筛选得到茵陈有效成分15个,作用靶点289个,其中肿瘤抑制蛋白基因53(TP53)、肿瘤坏死因子(TNF)、蛋白激酶1(AKT1)、白细胞介素-6(IL-6)、基质金属蛋白酶9(MMP9)、胱天蛋白酶3(CASP3)、缺氧诱导因子1A(HIF1A)和B细胞淋巴瘤2(BCL2)等为核心靶点。GO功能和KEGG通路富集分析结果主要涉及激素的反应、细胞迁移的正向调节、对细菌来源分子的反应、磷代谢过程的正向调节、对外源性刺激的反应等生物过程及癌症途径、血脂与动脉粥样硬化、磷脂酰肌醇-3-激酶-蛋白激酶(PI3K-Akt)、Janus激酶-信号传导及转录激活蛋白(JAK-STAT)、核因子-κB(NF-κB)等信号通路。结论:茵陈干预肝纤维化具有多成分、多靶点、多途径的特点,可为进一步研究提供参考。

关键词：肝纤维化茵陈网络药理学作用机制