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非线性能量采集的工业物联网非线性信息年龄分析

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计算机工程 2024年第8期50卷 198-206页

作者：许晋贾向东韩向花张兴元西北师范大学计算机科学与工程学院甘肃兰州730070 南京邮电大学江苏省无线通信重点实验室江苏南京210003

针对工业物联网(IIoT)中对信息新鲜性日益增长的需求,提出一种基于非线性能量采集(EH)的IIoT监控系统,配备电池容量大小为B的传感器节点,从无线供电基站(WPS)使用非线性EH技术采集射频(RF)能量进行充电,电池充满后将采集到的数据发送给... 详细信息

针对工业物联网(IIoT)中对信息新鲜性日益增长的需求,提出一种基于非线性能量采集(EH)的IIoT监控系统,配备电池容量大小为B的传感器节点,从无线供电基站(WPS)使用非线性EH技术采集射频(RF)能量进行充电,电池充满后将采集到的数据发送给数据采集节点。此外,针对在复杂场景中需要设置多个非线性信息年龄(AoI)算法所存在系统较为复杂的问题,提出1个普适函数来描述不同的非线性AoI,并通过调节参数来控制函数图像形状。在推导系统非线性AoI封闭表达式的同时引入系统能量效率(EE),以两者的比值Ψ作为系统的性能指标。鉴于问题较为复杂,采用一维搜索方法来寻找最优电池容量。通过系统仿真和数值分析,证明了存在最优的电池容量B使系统Ψ最小化。仿真结果表明,信道衰落参数、状态更新大小、WPS发射功率等参数都会对系统的性能产生影响,在相关系统的优化设计时都需要考虑。当WPS发射功率为0.5 W时,指数型非线性AoI下的Ψ是对数型非线性的2倍,是线性的1.8倍。

关键词：工业物联网非线性能量采集传输正确概率非线性信息年龄能量效率

Macroporous-mesoporous C-,S-,N-doped titania microspheres via the polyHIPE microspheres templates

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Chinese Chemical Letters 2021年第3期32卷 1135-1138页

作者： Xiaoling Cui Huarong Liu xingyuan zhang Hewen Liu CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Doping and increasing specific surface area by forming highly porous structures are two effective ways to enhance the photocatalytic performances of TiO_(2) *** re for the first time,we report a new facile method to prepare the macroporous-mesoporous C-,S-,N-doped TiO_(2)(C/S/N-TiO_(2))microspheres via polyHIPE microsphe res as *** chemical and crystalline structure s of these hierarchical porous TiO_(2) microspheres are analyzed with FTIR,XPS,EDS,and *** macroporous-mesoporous structures are confirmed with SEM observation and BET ***-vis DRS spectra analysis shows that the band gaps of C doped TiO_(2),C/N doped TiO_(2),C/S doped TiO_(2) and C/S/N doped TiO_(2) are estimated to be 3.07,3.01,2.94 and 2.81 eV,respectively,which are significantly narrower than that of TiO_(2) nanoparticles(3.23 eV).Photoluminescence spectra demonstrate that the recombination of electrons and holes in these macroporous-mesoporous TiO_(2) microspheres is also *** hierarchical porous C/S/N-TiO_(2) microspheres show high visible-light catalytic efficiency and excellent cycling stability to degrade RhB dye.

关键词： Porous titania microspheres PolyHIPE microspheres Hierarchical porous structure Heteroatom doping Photocatalysis

政策主题视角下我国政府数据治理政策演进研究

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情报探索 2024年第5期 87-95页

作者：吴涵肖明郭珺曜张星渊徐卓琪国家方志馆北京100021 北京师范大学政府管理学院北京100875

[目的/意义]我国政府数据治理框架处于不断的发展过程之中,分析数据治理的政策主题的演进与变迁,能够梳理政策发展脉络,指导数据治理政策体系的发展与完善。[方法/过程]系统收集中央层面政府数据治理政策,建构发展阶段,并借助LDA主题模... 详细信息

[目的/意义]我国政府数据治理框架处于不断的发展过程之中,分析数据治理的政策主题的演进与变迁,能够梳理政策发展脉络,指导数据治理政策体系的发展与完善。[方法/过程]系统收集中央层面政府数据治理政策,建构发展阶段,并借助LDA主题模型提取各阶段的重点主题,分析我国政府数据治理政策关注重点的演变与各阶段特征。[结果/结论]我国政府数据治理政策沿着“发展环境酝酿—政府数据价值释放—社会数据化转型”的路径不断演变发展,覆盖范围逐渐从政府内部拓宽至全社会,作用机制逐渐从政府主导转向鼓励市场发展,作用环节逐渐从数据收集、组织扩散至开发、利用等数据生命周期各环节,但数据安全问题始终是关注重点。

关键词：数据治理 LDA主题模型文本挖掘政策演进

Effects of yttrium on microstructure and mechanical properties of Mg-6Al magnesium alloy

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China Foundry 2010年第4期7卷 362-366页

作者： Ren Wenliang Li Quan＇an Li Jianhong Li Kejie zhang xingyuan School of Material Science and Engineering Henan University of Science and Technology Luoyang 471003 China School of Material Science and Engineering Xi＇an University of Technology Xi＇an 710048 China

Since Y has a great solid solubility in magnesium alloys, it helps enhancing the heat-resistant property of magnesium alloys. The effects of Y on microstructures and mechanical properties of Mg-6Al alloy have been studied in this work. The results show that Y addition refines grains of Mg-6Al alloy, and reduces the amount of the Mg 17 Al 12 phase. At the same time, the high melting-point Al 2 Y phase particles are formed. According to the mathematical model of the two-dimensional lattice misfit proposed by Braffit, it is believed that the Al 2 Y particles can serve as the nucleation sites for α-Mg. After T6 treatment, both elongation and ultimate tensile strength of Mg-6Al alloy at the room temperature and high-temperature increased firstly and then decreased, with increasing Y addition. The peak mechanical properties were achieved in the Mg-6Al-1.2Y alloy system. Y addition appears to change the fracture characteristic of Mg-6Al alloy. With 1.2wt%Y, the fracture surface of the alloy showed a lot of dimples and tearing ridges which connected the microscopic dimples and the fracture is mixed fracture of quasi-cleavage and ductile fracture.

关键词： yttrium Mg-6Al alloy microstructure mechanical properties

Mechanical Proofs about BW Multi-Party Contract Signing Protocol

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1516-1520页

作者： zhang Ningrong zhang xingyuan WANG Yuanyuan Institute of Command Automation PLA University of Science and Technology Nanjing 210007 Jiangsu China

We report on the verification of a multi-party contract signing protocol described by Baum-Waidner and Waidner （BW）. Based on Paulson＇s inductive approach, we give the protocol model that includes infinitely many signatories and contract texts signing simuhaneously. We consider composite attacks of the dishonest signatory and the external intruder, formalize cryptographic primitives and protocol arithmetic including attack model, show formal description of key distribution, and prove signature key secrecy theorems and fairness property theorems of the BW protocol using the interactive theorem prover Isabelle/HOL.

关键词： formal verification multi-party contract signing protocol inductive approach model

自拟消疣汤治疗扁平疣的临床疗效及对相关免疫因子水平的影响

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中国民间疗法 2024年第6期32卷 58-61页

作者：马成张兴元刘炜明陈焕新甘肃省徽县人民医院甘肃陇南742300

目的:观察自拟消疣汤治疗扁平疣的临床疗效及对相关免疫因子水平的影响。方法:将66例扁平疣患者随机分为对照组和观察组,每组33例。对照组给予维A酸乳膏外涂治疗,观察组给予消疣汤治疗,治疗14d后评定疗效,比较两组患者治疗前后皮损数量... 详细信息

目的:观察自拟消疣汤治疗扁平疣的临床疗效及对相关免疫因子水平的影响。方法:将66例扁平疣患者随机分为对照组和观察组,每组33例。对照组给予维A酸乳膏外涂治疗,观察组给予消疣汤治疗,治疗14d后评定疗效,比较两组患者治疗前后皮损数量、大小、颜色、瘙痒程度积分和血清免疫球蛋白G(IgG)、免疫球蛋白M(IgM)及白细胞介素-4(IL-4)水平,以及随访1、3、6个月复发情况。结果:观察组总有效率为96.97%(32/33),高于对照组的72.73%(24/33),差异具有统计学意义(P<0.05)。治疗后,两组患者皮损数量、大小、颜色、瘙痒程度积分均较治疗前降低,且观察组均低于对照组,差异均有统计学意义(P<0.05)。治疗后,两组患者IgG、IgM水平均较治疗前升高,IL-4水平较治疗前降低,差异均有统计学意义(P<0.05);两组患者IgG、IgM、IL-4水平组间比较,差异均有统计学意义(P<0.05)。治疗后随访1、3、6个月,观察组复发率均低于对照组,差异均有统计学意义(P<0.05)。结论:自拟消疣汤治疗扁平疣对皮损具有显著效果,可改善炎症因子水平,降低复发率。

关键词：消疣汤扁平疣皮损积分免疫球蛋白白细胞介素-4

Microstructure and mechanical properties of Mg-6Al magnesium alloy with yttrium and neodymium

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China Foundry 2009年第2期6卷 124-128页

作者： Chen Jun Li Quanan Li Jianghong Li Xiaofeng Li Kejie zhang xingyuan School of Material Science and Engineering Henan University of Science and Technology Luoyang 471003 China

The effects of rare earth(RE) elements Y and Nd on the microstructure and mechanical properties of Mg-6Al magnesium alloy were *** results show that a proper level of RE elements can obviously ref ine the microstructure of Mg-6Al magnesium alloys,reduce the quantity of β-Mg17Al12 phase and form Al2Y and Al2Nd *** combined addition of Y and Nd dramatically enhances the tensile strength of the alloys in the temperature range of 20-175℃.When the content of RE elements is up to 1.8%,the values of tensile strength at room temperature and at 150℃ simultaneously reach their maximum of 253 MPa and 196 MPa,*** main mechanisms of enhancement in the mechanical properties of Mg-6Al alloy with Y and Nd are the grain ref ining strengthening and the dispersion strengthening.

关键词： Y Nd Mg-6Al magnesium alloy microstructure elevated mechanical properties

Regularly Tuning Quantum Interference in Single-Molecule Junctions through Systematic Substitution of Side Groups with Varied Electron Effects

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Chinese Journal of Chemistry 2024年第11期42卷 1217-1222页

作者： Xianjing Xie Yirong zhang Junrui zhang xingyuan Cui Wei Liu Xunshan Liu Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang Province School of Chemistry and Chemical EngineeringZhejiang Sci-Tech University928 Second StreetHangzhouZhejiang310018 China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin130022 China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjingJiangsu210094 China

Investigating the quantum interference effect in single molecules is essential to comprehensively understand the underlying mechanism of single-molecule charge *** this study,we employed the mother molecule m-OPE and introduced a series of side groups with various electronic effects at the 2-position of the central phenyl ring,creating four daughter m-OPE *** single molecular conductivities of these molecule wires were measured using the scanning tunneling microscope breaking junction *** findings demonstrate that the substitutions regularly modulate the destructive quantum interference occurring within the m-OPE *** combining optical and electrochemical investigations,along with density functional theory computations,we discover that the conductivity of the molecules corresponds to the electron-donating/withdrawing ability of the ***,by adjusting the electron structures of the molecular backbone,we can systematically tailor the destructive quantum interference in the m-OPE molecules.

关键词： Quantum interference Single-molecule junctions Electron effect substituents Charge transport Molecular devices

Effects of Sb,Sm, and Sn additions on the microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd alloy

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Rare Metals 2009年第5期28卷 516-522页

作者： LI Kejie LI Quanan JING Xiaotian CHEN Jun zhang xingyuan School of Materials Science and Engineering Xi ＇an University of Technology Xi ＇an 710048 China School of Materials Science and Engineering Henan Universiry of Science and Technology Luoyang 471003 China

The microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd magnesium alloy with Sb, Sm, or Sn addition were investigated through X-ray diffraction （XRD）, optical microscopy （OM）, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. The results show that small amounts of Sb, Sm, and especially Sn can refine the grains of the alloy. High melting point Sb3Y5, Al2Sm, and Nd5Sn3 intermetallic compounds can be formed respectively when Sb, Sm, and Sn are added to the alloy. Sb and Sm can improve the tensile strength of the alloy at ambient and elevated temperatures. The tensile strength of the alloy with Sm addition is the highest at 293 and 423 K. However, the tensile strength of the alloy with Sn addition is the highest at 448 K.

关键词： magnesium alloys mechanical properties microstructure Sb Sm Sn