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Determination of crop and soil evaporation coefficients for estimating evapotranspiration in a paddy field

International Journal of Agricultural and Biological Engineering 2017年第4期10卷 130-139页

作者： Yan Haofang Zhang Chuan Hiroki Oue peng guangjie Ransford Opoku Darko Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China Institute of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China United Graduate School of Agricultural Sciences Ehime University3-5-7 TarumiMatsuyama790-8566Japan Department of Water Management Delft University of TechnologyDelft2600GAthe Netherlands

Accurate estimation of evapotranspiration is important in efficient water management for improving water use efficiency.In order to obtain evapotranspiration and evaporation beneath the canopy using the Food and Agriculture Organization(FAO)method,pan evaporation was used instead of reference evapotranspiration calculated by the Penman-Monteith equation with detailed meteorological data.The total crop coefficient and soil evaporation coefficient were determined using actual measured daytime evapotranspiration and evaporation by the Bowen ratio energy balance and lysimeter,respectively,in a rice paddy field in Japan.The average evapotranspiration was 5.3 mm/d,4.4 mm/d,7.4 mm/d and 6.3 mm/d and crop coefficient was 0.79,1.18,1.01 and 0.86 for the initial stage,development stage,middle-season stage and late-season stage,respectively.The evaporation was low and almost constant with an average value around 0.77 mm/d when the leaf area index(LAI)reached 3.The proposed average crop coefficients for different growing stages were applied to estimate daytime evapotranspiration and found suitable.A simple soil water evaporation coefficient model was developed using leaf area index for practical use and it was found that it could accurately estimate evaporation.

关键词： evapotranspiration evaporation paddy field lysimeter leaf area index(LAI) Bowen ratio energy balance

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基于ARMA模型的海上风机随机风场模拟

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武汉大学学报（工学版） 2024年第1期57卷 112-120页

作者：李鹏朱洪泽骆光杰苏凯浙江华东工程咨询有限公司浙江杭州310014 武汉大学水资源工程与调度全国重点实验室湖北武汉430072 武汉大学水工岩石力学教育部重点实验室湖北武汉430072 武汉大学海绵城市建设水系统湖北省重点实验室湖北武汉430072

为分析风荷载作用下的海上风机结构动力响应特性,提出采用数值仿真的方法模拟其空间域内的随机风场。利用MATLAB软件编制基于ARMA(autoregressive moving average)模型的脉动风速时程模拟程序,并嵌入AIC(Akaike’s information theoret... 详细信息

为分析风荷载作用下的海上风机结构动力响应特性,提出采用数值仿真的方法模拟其空间域内的随机风场。利用MATLAB软件编制基于ARMA(autoregressive moving average)模型的脉动风速时程模拟程序,并嵌入AIC(Akaike’s information theoretic)准则以判定ARMA模型的最优阶数,最终,针对江苏黄海某海上风机项目进行数值仿真分析,将模拟脉动风速功率谱与目标Davenport谱进行对比。计算结果表明:根据AIC准则确定的ARMA模型最优阶数可兼顾模型模拟精度和计算成本;模拟脉动风速时程功率谱函数在0.3 Hz以下的低频区间波动较大,与目标谱函数存在一定差距,在中高频段两者规律差距较小,整体模拟精度较高。

关键词：海上风机 ARMA模型 AIC Davenport功率谱 MATLAB 脉动风速时程

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无孔型轧制电极扁钢方坯表面垂直度计算与分析

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河北冶金 2024年第5期 46-49,70页

作者：韩广杰赵亚萍李宝秀林鹏河北机电职业技术学院河北邢台054000 邢台市模具材料技术创新中心河北邢台054000

电极扁钢又称作阴极扁钢,主要用于电解铝行业中的阴极电解电极,代表牌号有Q195、Q215、Q235。为满足钢坯尺寸的多样化,使用无孔型轧制,依靠压下量的精确设计满足客户需要。与限制孔型轧制相比,无孔型轧制的关键技术在于通过轧制参数设... 详细信息

电极扁钢又称作阴极扁钢,主要用于电解铝行业中的阴极电解电极,代表牌号有Q195、Q215、Q235。为满足钢坯尺寸的多样化,使用无孔型轧制,依靠压下量的精确设计满足客户需要。与限制孔型轧制相比,无孔型轧制的关键技术在于通过轧制参数设计保证钢坯的表面垂直度。以280 mm×325 mm方坯为研究对象,进行了无孔型轧制计算。由于方坯和轧辊结构对称,将模型简化为1/4模型,调整和优化道次压下量、轧制速度、轧制出口高度和宽度等参数,得到截面尺寸为165 mm×210 mm的方坯。该方坯在Z轴的高度由中心向两侧逐渐升高,上表面的表面垂直度为2.7 mm,在Y轴的宽度由中心向两侧逐渐缓慢增加,左侧面的表面垂直度仅为0.4 mm,模型对轧辊间距的简化处理对钢坯形变没有产生影响。根据对称分布关系,该无孔型轧制模型的参数设计可以满足方坯对4个表面的垂直度在3 mm以内的要求,为电极扁钢方坯的实际生产提供了理论依据。

关键词：电极扁钢无孔型轧制压下量表面垂直度

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Dynamic Balance of pSTAT1 and pSTAT3 in C57BL/6 Mice Infected with Lethal or Nonlethal Plasmodium yoelii

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Cellular & Molecular Immunology 2008年第5期5卷 341-348页

作者： Xibao Shi Li Qin guangjie Liu Siting Zhao Nanzheng peng Xiaoping Chen Guangzhou Institute of Biomedicine and Health Chinese Academy of Science Guangzhou 510663 China School of Life Sciences University of Science and Technology of China Hefei 230027 China Laboratory of Pathogen Biology Guangzhou Institute of Biomedicine and Health Chinese Academy of Sciences Guangzhou Science Park Guangdong 510663 China

Signal transducer and activator of transcription （STAT） proteins play an important role in cytokine signaling pathways and regulation of immune responses. The balance of the phosphorylated （activated） STAT1 （pSTAT1） and STAT3 （pSTAT3） has been documented in cancer immunology. In this study, we investigated the dynamic balance of pSTAT1 and pSTAT3 in C57BL/6 mice infected with either a nonlethal （Py17XNL） or lethal （Py17XL） strain of Plasmodium yoelii. Both Py17XNL and Py17XL infections induced a maximum activation of STAT1 and STAT3 on the first day after parasite inoculation. Additionally, the Py17XNL infection induced a pSTAT1- dominant response in mice during the early stage of infection, with the resolution of parasitemia. In contrast, Py17XL infection induced a pSTAT3-dominant response during the early phase of infection, with the death of the animals. Our results indicated that maximum activation of STAT1 and STAT3 occurred much earlier than the peak levels of cytokines induced by Plasmodium yoelii infection based on previous reports and that infection with Py17XNL and Py17XL induced different dynamic patterns of pSTAT1 and pSTAT3 balance.

关键词： malaria Plasmodium yoelii pSTAT1 pSTAT3

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Microstructure Evolution of Cast Al-Si-Cu Alloys in Solution Treatment

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 184-188页

作者： ZHANG Dingfei peng Jian HUANG guangjie ZENG Dingding College of Materials Science and Engineering Chongqing University Chongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing 400044 China

开发一个软件在演员组铝合金的热处理期间预言微观结构的进化和机械性质的开发，我们在解决方案处理期间为溶质的再分配建模多部件合金。solidifi 阳离子模拟软件的预言或实验的结果为热处理的模拟提供了起始的微观结构和溶质分发。通... 详细信息

开发一个软件在演员组铝合金的热处理期间预言微观结构的进化和机械性质的开发，我们在解决方案处理期间为溶质的再分配建模多部件合金。solidifi 阳离子模拟软件的预言或实验的结果为热处理的模拟提供了起始的微观结构和溶质分发。通过有硅，铜，镁，和铁的五的铝合金的二进制代码被建模。基本模型假定本地平衡(不在由于成核或生长冷却下面) 并且在稳固的成分的计算散开在团结期间。微观结构的进化被质、量的金属组织学在答案处理期间跟随。为第三的合金 Al-7%Si-3.5%Cu 的模拟的结果与试验性的观察相比。

关键词：铝硅铜合金铸造溶液温度微观结构

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Compressive Measurement Identification of Linear Time-Invariant System Application in DC Motor

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Journal of Beijing Institute of Technology 2019年第3期28卷 399-409页

作者： peng Qiu Qian Dong Mingqian Li guangjie Zhai Xueyan Wang Key Laboratory of Electronics and Information Technology for Space System National Space Science CentreChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Information Science and Technology University Beijing 100192China

In traditional system identification (SI), actual values of system parameters are concealed in the input and output data;hence, it is necessary to apply estimation methods to determine the parameters. In signal processing, a signal with N elements must be sampled at least N times. Thus, most SI methods use N or more sample data to identify a model with N parameters;however, this can be improved by a new sampling theory called compressive sensing (CS). Based on CS, an SI method called compressive measurement identification (CMI) is proposed for reducing the data needed for estimation, by measuring the parameters using a series of linear measurements, rather than the measurements in sequence. In addition, the accuracy of the measurement process is guaranteed by a criterion called the restrict isometric principle. Simulations demonstrate the accuracy and robustness of CMI in an underdetermined case. Further, the dynamic process of a DC motor is identified experimentally, establishing that CMI can shorten the identification process and increase the prediction accuracy.

关键词： system identification (SI) compressive sensing (CS) signal measurement linear time-invariant (LTI) system

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Phonon-assisted upconversion in twisted two-dimensional semiconductors

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Light(Science & Applications) 2023年第1期12卷 89-98页

作者： Yuchen Dai pengfei Qi Guangyi Tao guangjie Yao Beibei Shi Zhixin Liul Zhengchang Liu Xiao He Pu peng Zhibo Dang Liheng Zheng Tianhao Zhang Yongji Gong Yan Guan Kaihui Liu Zheyu Fang School of Physics State Key Laboratory for Mesoscopic PhysicsAcademy for Advanced Interdisciplinary StudiesCollaborative Innovation Center of Quantum MatterNano-optoelectronics Frontier Center of Ministry of EducationPeking University100871 BeijingChina Institute of Modern Optics Nankai UniversityTianjin Key Laboratory of Micro-scale Optical Information Science and Technology300350 TianjinChina Photonics Research Center School of PhysicsMOE Key Lab of Weak-Light Nonlinear Photonicsand Tianjin Key Lab of Photonics Materials and Technology for Information ScienceNankai University300071 TianjinChina School of Materials Science and Engineering Beihang University100191 BeijingChina Center for Physicochemical Analysis and Measurements in ICCAS Analytical Instrumentation CenterPeking University100871 BeijingChina

Phonon-assisted photon upconversion(UPC)is an anti-Stokes process in which incident photons achieve higher energy emission by absorbing phonons.This letter studies phonon-assisted UPC in twisted 2D semiconductors,in which an inverted contrast between UPC and conventional photoluminescence(PL)of WSe2 twisted bilayer is emergent.A 4-fold UPC enhancement is achieved in 5.5°twisted bilayer while PL weakens by half.Reduced interlayer exciton conversion efficiency driven by lattice relaxation,along with enhanced pump efficiency resulting from spectral redshift,lead to the rotation-angle-dependent UPC enhancement.The counterintuitive phenomenon provides a novel insight into a unique way that twisted angle affects UPC and light-matter interactions in 2D semiconductors.Furthermore,the UPC enhancement platform with various superimposable means offers an effective method for lighting bilayers and expanding the application prospect of 2D stacked van der Waals devices.

关键词： twisted semiconductors relaxation

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Current Research and Development on Deformation and Fixation of Bended Wood and Wood-based Composites

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Chinese Forestry Science and Technology 2007年第2期6卷 30-35页

作者： CHEN peng ZHAO guangjie College of Material Science and Technology Beijing Forestry University Beijing 100083 P R. China

There are many advantages of bended wood,such as good-looking shape,simple process and low cost.The product,however,is easy to get recovery,which is urgent to be dealt with.This paper concludes the features of deformation and recovery of bended wood and wood-based composites and summarizes four treating methods to keep dimensional stability.Compared to bended solid wood,some elementary perspectives on the research of bended wood-based composites are presented.The purpose of this paper is to suggest:1)to investigate the optimum heating time and temperature that bended wood and wood-based composites need from the formation of deformation to the recovery and to the permanent fixation,according to its changes of dimensional stability such as curvature radius;2)to measure the composites comprised of wood and adhesives on the changes of stress relaxation,dynamic viscoelasticity and crystal1ization field;3)to quantitatively analyze changes of the major components in wood cell wall polymers as well as the composites under heat/steam treatment and untreated conditions.It will be helpful for subsequent research to clarify on the mechanisms of permanent fixation of bended wood and also contribute to that of wood-based composites.

关键词：弯曲木材复合板变形现象固定作用

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Effects of the Land Use Change on Ecosystem Service Value Based on RS & GIS

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Journal of Landscape Research 2015年第1期7卷 21-26页

作者： peng Wenfu WANG guangjie ZHOU Jieming XU Xinliang College of Geography and Resources Sichuan Normal University Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of Education Sichuan Normal University Data Center for Resources and Environmental Sciences Chinese Academy of Sciences (RESDC)

Assessing the effect of land use change on ecosystem service value(ESV) can provide reference for sustainable land use and ecological environment protection. The land use information was extracted and analyzed based on Landsat TM images in Shuangliu County, Sichuan Province from 1992 to 2008, following remote sensing(RS) and GIS. The ESV of the land use change in study area was evaluated by adopting the service value method within Chinese terrestrial ecosystem. The results showed that:(1) the area of paddy field and forest land reduced in the 16 years, total area of construction land expanded fast on the basis of occupying paddy field and forest land.(2) The regional ESV increased by 4,508.859×104 RMB, but there is different change trend at different times, such as the ESV fell by 10.59% in 1992–2000, increased by 16.024% in 2000–2008.(3) The conversion from forest land and cultivated land to construction land caused a decline and negative flow in ESV, the total value was 2,197.233×104 RMB and 5,317.460×104 RMB.(4) All land use types showed that change of the ESV coefficient was less elastic, the relative sensitivity: forest land > cultivated land > water area. In terms of variability of ESV, water area change had greater influence on the change of ESV in the study area, and cultivated land and forest land had relatively smaller impact.

关键词： Land use type change Ecosystem service value(ESV) Shuangliu County Remote sensing(RS) GIS

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切顶留巷注浆加固技术研究与应用

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中国煤炭 2022年第S1期48卷 266-274页

作者：彭涛张广杰王文国能神东煤炭集团有限责任公司哈拉沟煤矿生产办陕西省榆林市719315 河南理工大学能源科学与工程学院河南省焦作市454003 煤炭安全生产与清洁高效利用省部共建协同创新中心河南省焦作市454000

基于切顶卸压沿空留巷围岩变形破坏严重且难以控制的问题,以哈拉沟煤矿12201工作面地质和开采条件为工程研究背景,采用现场调研、理论分析和现场试验的综合手段,对沿空留巷围岩变形破坏特征展开了研究分析,并提出分层次耦合注浆加固技... 详细信息

基于切顶卸压沿空留巷围岩变形破坏严重且难以控制的问题,以哈拉沟煤矿12201工作面地质和开采条件为工程研究背景,采用现场调研、理论分析和现场试验的综合手段,对沿空留巷围岩变形破坏特征展开了研究分析,并提出分层次耦合注浆加固技术应用在沿空留巷中。研究结果表明,引起留巷围岩破坏的关键原因是顶板及帮部裂隙发育无法承受其覆岩关键层断裂压力;对顶、帮进行分层次耦合注浆加固能够改善留巷四周煤岩体的应力环境,形成再造承载层结构,提高留巷整体承载能力。现场注浆后留巷破坏得以有效控制,两帮最大收缩量381 mm、顶板最大下沉量128 mm、最大底鼓量227 mm,顶板离层量仅为73 mm,锚索受力仅为345 kN;留巷能够满足接替工作面正常生产使用的要求。

关键词：切顶卸压沿空留巷围岩注浆加固顶板

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