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电力信息物理系统建模与故障分析

计算机仿真 2024年第2期41卷 74-80页

作者：胡福年郭旭陈军江苏师范大学电气工程及自动化学院江苏徐州221116

针对电力信息物理系统分层建模中信息层数据转发关系表达不清晰的问题,建立了考虑前置机数据转发功能的电力信息物理系统模型。基于信息物理交互视角,通过对信息流流动过程进行分析并结合电力信息物理系统结构与功能特性,将电力信息物... 详细信息

针对电力信息物理系统分层建模中信息层数据转发关系表达不清晰的问题,建立了考虑前置机数据转发功能的电力信息物理系统模型。基于信息物理交互视角,通过对信息流流动过程进行分析并结合电力信息物理系统结构与功能特性,将电力信息物理系统分为数据上传与数据下发两个部分进行建模。数据上传与下发过程中分别建立决策接收矩阵与前置机数据下发矩阵以表达信息流横向流动过程。在数据上传部分建立数据预处理矩阵以表征电力信息系统自动调控能力。最后以IEEE30节点系统为例进行模型推演与故障分析以验证模型的有效性,仿真结果表明,所提模型对多种故障情形下的数据流动分析具有普适性。

关键词：信息物理系统信息流数据转发:故障分析

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氮添加对水杉防护林生长的影响

林业科学研究 2024年第5期37卷 186-194页

作者：姚洪锡冯坤乔童冉原文文吴统贵朱念福荣成市国有成山林场山东威海264300 江苏省东台市林场江苏东台224200 中国林业科学研究院亚热带林业研究所浙江杭州311400 国家林业和草原局华东沿海防护林生态系统定位观测研究站浙江杭州311400

[目的]在我国大气氮沉降量逐年增加背景下,厘清外源氮素输入对水杉防护林生长的影响,有助于为防护林健康生长开展养分管理提供科学指导。[方法]以江苏省东台市泥质海岸12年生水杉(Metasequoia glyptostroboides)防护林为研究对象,通过设... 详细信息

[目的]在我国大气氮沉降量逐年增加背景下,厘清外源氮素输入对水杉防护林生长的影响,有助于为防护林健康生长开展养分管理提供科学指导。[方法]以江苏省东台市泥质海岸12年生水杉(Metasequoia glyptostroboides)防护林为研究对象,通过设置4个水平的连续8 a氮添加处理,即对照(CK,0 kg·hm^(-2)·a^(-1))、低氮(LN,56 kg·hm^(-2)·a^(-1))、中氮(MN,168 kg·hm^(-2)·a^(-1))和高氮(HN,280 kg·hm^(-2)·a^(-1)),研究氮添加对水杉及其大小树(根据初始平均胸径划分)胸径年生长量的影响。[结果]氮添加水平和年份及其交互作用显著影响水杉胸径年生长量。氮添加对水杉胸径年生长量呈非线性影响,中氮添加的促进作用强于低氮和高氮。年际间水杉胸径生长量的变化趋势一致:初期氮添加促进作用逐渐增强(1—3年氮添加),然后促进逐渐减弱(4—6年氮添加),继而转变为抑制作用(7—8年氮添加)。在同水平氮添加处理下,径级和年份显著影响水杉生长,但无交互作用。对于小树,氮添加水平和年份及其交互作用显著影响胸径生长。对于大树,仅氮添加年份显著影响胸径生长。水杉小树的胸径年生长量低于大树,而生长量响应比则高于大树。[结论]同水平氮添加处理下,水杉大树胸径生长量高于小树,但氮添加对小树胸径生长的促进作用强于大树,表明小树生长更易受外源氮输入的调控。同时,随着年份增加,氮添加对水杉胸径生长表现出先促进后抑制,表明长期氮沉降将不利于泥质海岸水杉防护林生长。

关键词：氮添加水杉防护林胸径年生长量小树大树

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An Improved Control Algorithm for High-order Nonlinear Systems with Unmodelled Dynamics

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International Journal of Automation and computing 2009年第3期6卷 234-239页

作者： Na Duan fu-nian Hu Xin Yu School of Electrical Engineering ＆ Automation Xuzhou Normal University Xuzhou 221116 PRC Institute of Automation Qufu Normal University Qufu 273165 PRC

In this paper, we consider a class of high-order nonlinear systems with unmodelled dynamics from the viewpoint of maintaining the desired control performance （e,g., asymptotical stability） and reducing the control effort. By introducing a new reseating transformation, adopting an effective reduced-order observer, and choosing an ingenious Lyapunov function and appropriate design parameters, this paper designs all improved output-feedback controller. The output-feedback controller guarantees the globally asymptotieal stability of the closed-loop system. Subsequently, taking a concrete system for an example, the smaller critical values for gain parameter and resealing transformation parameter are obtained to effectively reduce the control effort.

关键词： High-order nonlinear systems control effort reduction rescaling transformation globally asymptotical stability.

Optimal power allocation for two-way relaying over OFDM using physical-layer network coding

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 9-15,35页

作者： LI fu-nian ZHU Guang-xi WANG De-sheng Department of Electronic and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China Department of Electronic and Information Engineering Wuhan University of Science and Technology Wuhan 430081 China

In this paper, a network scenario of two-way relaying over orthogonal frequency division multiplexing （OFDM） is considered, in which two nodes intend to exchange the information via a relay using physical-layer network coding （PLNC）. Assuming that the full channel knowledge is available, an optimization problem, which maximizes the achievable sum rate under a sum-power constraint, is investigated. It is shown that the optimization problem is non-convex, which is difficult to find the global optimum solution in terms of the computational complexity. In consequence, a low-complexity optimal power allocation scheme is proposed for practice implementation. A link capacity diagram is first employed for power allocation on each subcarrier. Subsequently, an equivalent relaxed optimization problem and Karush-Kuhn-Tucker （KKT） conditions are developed for power allocation among each subcarrier. Simulation results demonstrate that the substantial capacity gains are achieved by implementing the proposed schemes efficiently with a low-complexity computational effort.

关键词： two-way relaying power allocation physical-layer network coding OFDM

Asymmetric hydroazidation ofα-substituted vinyl ketones catalyzed by chiral primary amine

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Chinese Chemical Letters 2017年第5期28卷 1083-1086页

作者： Zai-Kun Xue nian-Kai fu San-Zhong Luo Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SdencesBeijing 100190China

We report herein the first example of asymmetric hydroazidation of α-substituted vinyl ketones by using chiral primary amines as the catalysts.A simple chiral primary-tertiary diamine catalyst derived from lphenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step,thus enabling the effective synthesis of α-chiral β-azido ketones with good yields and moderate enantioselectivities.

关键词： Chiral primary amine catalysis Hydroazidation Enamine protonation α-Substituted vinyl ketones Aza-Michael addition Chiral β-azido ketones

幽门螺杆菌感染对正常结直肠黏膜-腺瘤-腺癌的影响

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临床消化病杂志 2024年第4期36卷 251-255页

作者：方年富何庆霞丁元军景德镇市第二人民医院消化内科江西景德镇333000

[目的]探讨幽门螺杆菌(Helicobacter pylori,Hp)与结直肠肿瘤之间的相关性。[方法]回顾性分析同时接受Hp检测及结肠镜检查的患者2547例的临床资料,其中952例为结直肠肿瘤组,1595例结肠镜检查正常作为对照组,分析Hp阳性患者是否与结直肠... 详细信息

[目的]探讨幽门螺杆菌(Helicobacter pylori,Hp)与结直肠肿瘤之间的相关性。[方法]回顾性分析同时接受Hp检测及结肠镜检查的患者2547例的临床资料,其中952例为结直肠肿瘤组,1595例结肠镜检查正常作为对照组,分析Hp阳性患者是否与结直肠肿瘤存在相关性。[结果]男性Hp阳性、阴性患者中结直肠肿瘤发生率分别为45.27%、42.14%(P=0.279)。女性Hp阳性、阴性患者中结直肠肿瘤发生率分别为34.83%、29.91%(P=0.075)。Hp感染与增生性息肉、腺瘤、进展期腺瘤、结直肠癌存在正相关,比值比(odds ratio,OR)分别为1.19、1.17、1.38、1.38。多因素回归分析Hp感染对息肉、腺瘤及腺癌均存在显著影响(P<0.05)。[结论]Hp感染与结直肠息肉、腺瘤、腺癌的风险增加相关,而且Hp感染可能在正常结直肠黏膜-腺瘤-腺癌的早期发挥作用。

关键词：结直肠癌幽门螺杆菌腺瘤进展期腺瘤

Transparent conducting properties of c-axis-oriented NaxCoO2 epitaxial thin films

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Science China(Physics,Mechanics & Astronomy) 2018年第10期61卷 104-107页

作者： DaChao Yuan JiangLong Wang nian fu XiaoLin Wu YueJin Ma ShuFang Wang College of Mechanical and Electrical Engineering Agricultural University of Hebei Baoding 071001 China Hebei Key Lab of Optic-electronic Information and Materials College of Physics Science and Technology Hebei University Baoding 071002 China

Transparent conducting oxides （TCOs） have attracted in- tensive attention because of their broad application in pho- toelectric devices such as solar cells, light-emitting diodes, and flat-panel displays. Current TCOs used in industry, including tin （IV） oxide （SnOz）, indium oxide （In203）, indium tin oxide （ITO）, and zinc oxide （ZnO）, are primarily n-type semiconductors [1-3]. Suitable p-type TCOs are still being researched. In the past several decades, delafossite-type compounds CuMO2 （M = Cr, A1, Ga, Fe, Sc, Y） as well as NiO, Cr203, and MoO3 have been extensively studied as potential p-type TCO candidates [4-8].

关键词：取向附生锌氧化物性质电影太阳能电池 TCO 应用程序 MoO3

Quantifying key model parameters for wheat leaf gas exchange under different environmental conditions

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Journal of Integrative Agriculture 2020年第9期19卷 2188-2205页

作者： ZHAO fu-nian ZHOU Shuang-xi WANG Run-yuan ZHANG Kai WANG He-ling YU Qiang Key Laboratory of Water Cycle&Related Land Surface Processes/Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101P.R.China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049P.R.China Key Laboratory of Arid Climatic Change and Disaster Reduction of Gansu Province/Key Laboratory of Arid Climate Change and Disaster Reduction of China Meteorological Administration(CMA)/Lanzhou Institute of Arid Meteorology CMALanzhou 730020P.R.China The New Zealand Institute for Plant and Food Research Limited Hawke's Bay 4130New Zealand State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100P.R.China School of Life Sciences University of Technology SydneySydney 2000Australia

The maximum carboxylation rate of Rubisco(Vcmax)and maximum rate of electron transport(Jmax)for the biochemical photosynthetic model,and the slope(m)of the Ball-Berry stomatal conductance model influence gas exchange estimates between plants and the ***,there is limited data on the variation of these three parameters for annual crops under different environmental *** exchange measurements of light and CO2 response curves on leaves of winter wheat and spring wheat were conducted during the wheat growing season under different environmental *** were no significant differences for Vcmax,Jmax or m between the two wheat *** seasonal variation of Vcmax,Jmax and m for spring wheat was not pronounced,except a rapid decrease for Vcmax and Jmax at the end of growing *** and Jmax show no significant changes during soil drying until light saturated stomatal conductance(gssat)was smaller than 0.15 mol m^–2 s^–***,there was a significant difference in m during two different water supply conditions separated by gssat at 0.15 mol m^–2 s^–***,the misestimation of Vcmax and Jmax had great impacts on the net photosynthesis rate simulation,whereas,the underestimation of m resulted in underestimated stomatal conductance and transpiration rate and an overestimation of water use *** work demonstrates that the impact of severe environmental conditions and specific growing stages on the variation of key model parameters should be taken into account for simulating gas exchange between plants and the ***,modification of m and Vcmax(and Jmax)successively based on water stress severity might be adopted to simulate gas exchange between plants and the atmosphere under drought.

关键词： biochemical photosynthetic model stomatal conductance model maximum carboxylation rate of Rubisco maximum rate of electron transport drought

检测方法对20CrNiMoH钢奥氏体晶粒度的影响

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热处理技术与装备 2024年第1期45卷 53-55页

作者：董凤奎黄山刘年富钟芳华宝武杰富意特殊钢有限公司广东韶关512123 桂林福达齿轮有限公司广西桂林541199

奥氏体晶粒度是衡量钢材质量的一个重要指标,研究了奥氏体晶粒度显示方法对20CrNiMoH渗碳齿轮钢奥氏体晶粒度检测结果的影响。结果表明,氧化法和直接淬硬法检测的奥氏体晶粒度差别较小,渗碳法检测的奥氏体晶粒比氧化法和直接淬硬法低0.2... 详细信息

奥氏体晶粒度是衡量钢材质量的一个重要指标,研究了奥氏体晶粒度显示方法对20CrNiMoH渗碳齿轮钢奥氏体晶粒度检测结果的影响。结果表明,氧化法和直接淬硬法检测的奥氏体晶粒度差别较小,渗碳法检测的奥氏体晶粒比氧化法和直接淬硬法低0.2~0.3级,模拟渗碳法检测奥氏体晶粒度存在混晶现象。对造成模拟渗碳法出现混晶的原因进行了分析,并给出了改进措施,确保使用模拟渗碳法检测奥氏体晶粒度仍没有混晶现象出现。

关键词： 20CrNiMoH钢奥氏体晶粒度混晶

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