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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng xing Ye yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

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我国小豆种质资源的豆沙特性评价与筛选

植物遗传资源学报 2015年第4期16卷 883-887,894页

作者：王丽侠袁兴淼张涛王素华程须珍中国农业科学院作物科学研究所北京100081

对450份小豆种质资源进行了豆沙特性的评价,以期为培育豆沙专用品种提供信息。结果表明,不同小豆种质在出沙倍数、皮含量、湿沙颜色及淀粉细胞直径、壁厚等方面均存在一定差异。其中出沙倍数的变异范围为1.97-3.51,平均为2.51倍;皮含量... 详细信息

对450份小豆种质资源进行了豆沙特性的评价,以期为培育豆沙专用品种提供信息。结果表明,不同小豆种质在出沙倍数、皮含量、湿沙颜色及淀粉细胞直径、壁厚等方面均存在一定差异。其中出沙倍数的变异范围为1.97-3.51,平均为2.51倍;皮含量的变异在7%-21%之间,平均为9%;湿沙的亮度值的变异在9.48-34.38之间,平均为29.6;红色度和黄色度的变异范围分别为16.56-34.27、-1.71-17.86,平均分别为21.5、11.8。不同种质间淀粉细胞大小也存在较大差异,其中直径、周长的差异均在2倍以上,而壁厚的差异达20余倍。上述沙用指标在种质间的变异说明,豆沙专用品种的选育是必要且可行的。根据研究结果,筛选出豆沙特性指标均较好的小豆种质20份,有望为豆沙专用品种的培育奠定基础,保障豆沙生产的经济效益和食品安全等问题。

关键词：小豆豆沙特性评价筛选

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我国绿豆种质资源的芽用特性评价与筛选

植物遗传资源学报 2012年第5期13卷 879-883页

作者：袁兴淼张涛程须珍王丽侠王素华中国农业科学院作物科学研究所北京100081

对470份绿豆种质资源进行了芽用特性的评价,以期为培育豆芽专用品种提供信息。结果表明,不同绿豆品种生产的豆芽在芽体粗细、长短、外观色泽、口感以及豆芽产量等方面均存在差异。不同品种间的芽豆比变化范围为1.34～9.08,平均为6.17,... 详细信息

对470份绿豆种质资源进行了芽用特性的评价,以期为培育豆芽专用品种提供信息。结果表明,不同绿豆品种生产的豆芽在芽体粗细、长短、外观色泽、口感以及豆芽产量等方面均存在差异。不同品种间的芽豆比变化范围为1.34～9.08,平均为6.17,芽豆比与芽长成显著正相关(R=0.614),即芽长是豆芽产量的重要影响因子。研究还表明,芽长、芽豆比与百粒重均呈一定负相关,但与子粒蛋白质、脂肪、淀粉等品质性状相关不明显,即小粒绿豆资源更适于豆芽生产。其中绿豆豆芽因子叶花青甙含量高而导致芽体颜色不鲜亮、商品性差的绿豆资源占分析总数的84.47%。不同绿豆资源的硬实率、豆芽畸形率及烂豆率的变异范围分别为0～87.78%、0～85.56%和0～11.11%,且三者之间无显著相关性。根据芽用特性的综合评价,共筛选出12份低硬实、无烂芽、产量高、商品性好的绿豆种质资源,为豆芽专用品种的筛选与培育奠定了基础。

关键词：绿豆芽用特性评价

Vibration control simulation of beams with piezoelectric actuators using impedance and FEM

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Vibration control simulation of beams with piezoelectric act...

基于EST-SSR和SNP标记的大麦麦芽纯度检测

2011年全国压电和声波理论及器件应用研讨会

作者： Chang ZHENG~1 Xiao-Ran YIN~1 Guo-Qing LI~(1,2*) xing-yuan miao~1 1 Department of Engineering Mechanics,Huazhong University of Science and Technology,Wuhan 430074 2 Key Laboratory of Hubei for Engineering Structure Analysis and Safety Assessment,Wuhan 430074

＜正＞Vibration control simulations of beams with piezoelectric actuators using impedance method and FEM are presented in this *** first,one impedance matrix equation is used to describe the dynamic of one piezoelectric stretch actuator,and each impedance equation is equivalent to one mass-damping-spring（M-C-K） system.A FE harmonic analysis is carried out on piezoelectric stretch actuator and the equivalent system are determined by

关键词： Piezoelectric structure Impedance Vibration control Equivalent system FEM

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作物学报 2015年第8期41卷 1147-1154页

作者：张利莎董国清扎桑卓嘎王德良谷方红袁兴淼张京郭刚刚武汉轻工大学生物与制药工程学院湖北武汉430023 农业部作物种质资源与生物技术重点开放实验室/国家农作物基因资源与基因改良重大科学工程/中国农业科学院作物科学研究所北京100081 西藏大学农牧学院西藏林芝860000 中国食品发酵工业研究院北京100027

大麦麦芽作为啤酒酿造的主要原料之一,其纯度决定了麦芽原料的均一性,进而影响加工工艺和啤酒品质。为高效准确地鉴定麦芽纯度,在啤酒企业进行麦芽原料采购和质量监测时提供参考依据。本研究分别利用EST-SSR和SNP标记定性检测了按比例... 详细信息

大麦麦芽作为啤酒酿造的主要原料之一,其纯度决定了麦芽原料的均一性,进而影响加工工艺和啤酒品质。为高效准确地鉴定麦芽纯度,在啤酒企业进行麦芽原料采购和质量监测时提供参考依据。本研究分别利用EST-SSR和SNP标记定性检测了按比例预混的麦芽样品纯度,并利用SNP标记定量检测了4份送检的麦芽盲样纯度。结果表明,EST-SSR标记能定性检测混杂度高于10%的麦芽样品,而SNP标记能够有效鉴定混杂度低至5%的麦芽样品。SNP标记对纯度定量检测的单次抽样的测定值与真实值之间的误差在3%以内。比较发现,本研究所用的两类分子标记均可用于麦芽样品的纯度检测,但基于KASP技术的SNP标记可以满足麦芽纯度的快速定量检测需要。

关键词：大麦麦芽纯度检测分子标记 KASP技术

Particle characteristics and rheological constitutive relations of high concentration red mud

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Journal of China University of Mining and Technology 2008年第2期18卷 266-270页

作者： WANG xing QU yuan-yuan HU Wei-wei CHEN Jie ZHAO Xue-yi WU miao School of Electromechanical and Information Engineering China University of Mining ＆ Technology Beijing 100083 China Electromechanical Engineering and Technology Institute China University of Mining ＆ Technology Beijing 100083 China

Red mud has relatively small solid particles （d50= 13.02 μm） and will flow in paste form under high pressure during pipeline transport. Red mud belongs to a two-phase flow of materials with high viscosity and a high concentration of non-sedimentation, homogeneous solid-liquids. It is difficult to test its rheological properties under atmospheric pressure. Measurements such as rotational viscometry can not reflect the real state of the material when it is flowing in a pipe. Tested rheological parameters are somewhat higher than the actual values. In our investigation, grain shape, distinctive modality and grain size distribution of red mud were tested. Based on the principle of tube measurement, rheological experiments on red mud at different concentrations were carried out by using our independently developed tube-type pressure theology test facility, and obtained constitutive equations. We conclude that red mud behaves as non-Newtonian pseudo-plastic fluid in pipe flows. Its consistency and power-law indices vary considerably with different concentrations.

关键词： high concentration non-Newtonian fluid rheological constitutive relations red mud tube-pipe flow method tube-type pressure rheology test facility

Global Freshwater Storage Capability across Time Scales in the GRACE Satellite Era

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Advances in Atmospheric Sciences 2021年第6期38卷 905-917页

作者： Enda ZHU xing yuan Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Freshwater is recharged mainly by rainfall and stored inland for a period of time,which is directly affected by its storage *** storage capability of river basins has different spatiotemporal features that are important for the predictability of freshwater ***,the estimation of freshwater storage capability(FSC)remains a challenge due to the lack of observations and quantification ***,we use a metric that characterizes hydrological“inertia”after rainfalls to analyze FSC over the 194 largest global major river basins based on satellite observations from the Gravity Recovery and Climate Experiment(GRACE)and simulations from the Community Land Model version 5(CLM5).During 2003–16,the global land was observed to retain 28%of precipitation after one month based on GRACE observations,and the simulation depicts that the retained proportions decrease from 42%after one day to 26%after one month,with smaller FSC partly attributed to wetter conditions and higher vegetation *** root zone contributes about 40%to the global land FSC on daily to monthly time *** the time scale increases,the contribution from the surface soil decreases from 26%to 14%,while the contribution from the deep soil increases from 4%to 10%.Snow contributes over 20%of land FSC,especially over high *** six decades of CLM5 long-term simulations,it is revealed that the change of FSC in most basins is related to internal climate *** FSC of river basins which displays the proportion of precipitation retained on land is worthy of further attention regarding the predictability of water resources.

关键词： freshwater GRACE land surface model soil moisture climate variability storage capability

Underestimation of the Warming Trend over the Tibetan Plateau during 1998–2013 by Global Land Data Assimilation Systems and Atmospheric Reanalyses

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Journal of Meteorological Research 2020年第1期34卷 88-100页

作者： Peng JI xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049 School of Hydrology and Water Resources Nanjing University of Information Science&TechnologyNanjing 210044

Accurate surface air temperature(T2m)data are key to investigating eco-hydrological responses to global *** of sparse in-situ observations,T2m datasets from atmospheric reanalysis or multi-source observation-based land data assimilation system(LDAS)are widely used in research over alpine regions such as the Tibetan Plateau(TP).It has been found that the warming rate of T2m over the TP accelerates during the global warming slowdown period of 1998–2013,which raises the question of whether the reanalysis or LDAS datasets can capture the warming *** evaluating two global LDASs,five global atmospheric reanalysis datasets,and a high-resolution dynamical downscaling simulation driven by one of the global reanalysis,we demonstrate that the LDASs and reanalysis datasets underestimate the warming trend over the TP by 27%–86%during 1998–*** is mainly caused by the underestimations of the increasing trends of surface downward radiation and nighttime total cloud amount over the southern and northern TP,*** GLDAS2.0,ERA5,and MERRA2 reduce biases of T2m simulation from their previous versions by 12%–94%,they do not show significant improvements in capturing the warming *** WRF dynamical downscaling dataset driven by ERA-Interim shows a great improvement,as it corrects the cooling trend in ERA-Interim to an observation-like warming trend over the southern *** results indicate that more efforts are needed to reasonably simulate the warming features over the TP during the global warming slowdown period,and the WRF dynamical downscaling dataset provides more accurate T2m estimations than its driven global reanalysis dataset ERA-Interim for producing LDAS products over the TP.

关键词： land data assimilation system(LDAS) reanalysis datasets WRF dynamical downscaling Tibetan Plateau global warming slowdown

Two Types of Flash Drought and Their Connections with Seasonal Drought

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Advances in Atmospheric Sciences 2018年第12期35卷 1478-1490页

作者： Linying WANG xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

Flash drought is a rapidly intensifying drought with abnormally high temperature,which has greatly threatened crop yields and water supply,and aroused wide public concern in a warming ***,the preferable hydrometeorological conditions for flash drought and its association with conventional drought at longer time scales remain ***,we investigate two types of flash drought over China:one is high-temperature driven(Type Ⅰ),while the other is water-deficit driven(Type Ⅱ).Results show that the frequencies of the two types of flash drought averaged over China during the growing season are *** I flash drought tends to occur over southern China,where moisture supply is sufficient,while Type Ⅱ is more likely to occur over semi-arid regions such as northern *** types of flash drought increase significantly(p<0.01)during 1979–2010,with a doubled rise in Type Ⅰ as compared with Type Ⅱ.Composite analysis shows that high temperature quickly increases evapotranspiration(ET)and reduces soil moisture from two pentads before the onset of Type Ⅰ flash *** contrast,there are larger soil moisture deficits two pentads before the onset of Type Ⅱ flash drought,leading to a decrease in ET and increase in *** flash drought associated with seasonal drought,there is a greater likelihood of occurrence during the onset and recovery phases of seasonal drought,suggesting perfect conditions for flash drought during transition *** study provides a basis for the early warning of flash drought by connecting multiscale drought phenomena.

关键词： flash drought climate change soil moisture evapotranspiration seasonal drought