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杆系结构静/动力学计算的直接方法

上海交通大学学报 2016年第1期50卷 52-58,64页

作者：周俊饶柱石塔娜上海交通大学振动、冲击、噪声研究所上海200240 上海交通大学机械系统与振动国家重点实验室上海200240

针对有限单元法计算精度受网格密度制约的问题,提出一种求任意复杂杆系静、动力学问题精确解的方法.该方法基于节点分析法,逐个节点列位移相容方程和内力平衡方程,以谱系数作为未知数,杆件变形和截面内力则采用相应问题的精确解来描述.... 详细信息

针对有限单元法计算精度受网格密度制约的问题,提出一种求任意复杂杆系静、动力学问题精确解的方法.该方法基于节点分析法,逐个节点列位移相容方程和内力平衡方程,以谱系数作为未知数,杆件变形和截面内力则采用相应问题的精确解来描述.用代数符号化的方式,对方程系数矩阵的组建过程进行了详细描述,为通用程序编制提供依据.对建模过程中的分布式载荷和铰接接头的处理方法进行了探讨并给出处理方法.通过平面钢架屈曲分析和空间管路谐响应分析,证实所提方法具有计算精度高、划分单元数少的特点,特别适合于需要精确解的场合.

关键词：解析解节点法框架杆系梁

The Early Permian Woniusi Flood Basalts from the Baoshan Terrane, SW China: Petrogenesis and Geodynamic Implications

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2091-2114页

作者： CAO jun ZHANG Gaizhi WANG Xuan CHEN jun State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Shandong Key Laboratory of Depositional Mineralization&Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The Woniusi flood basalts from the Baoshan terrane,SW China,represent a significant eruption of volcanic rocks which were linked to the Late Paleozoic rifting of the Cimmeria from the northern margin of East ***,the precise mechanism for the formation and propagation of the rifting is still in *** we report 40 Ar/39 Ar dating,whole-rock geochemistry,and Sr-Nd-Pb isotopes for the Woniusi basalts from the Baoshan terrane of SW China,with the aim of assessing if a mantle plume was related to the formation of the continent Cimmeria.40 Ar/39 Ar dating of the Woniusi basalts yielded ages of 279.3±1.1 Ma and 273.9±1.5 Ma,indicating they were emplaced during the Early ***-rock geochemistry shows that these basalts have subalkaline tholeiitic affinity,low Ti O2(1.2-2.2 wt%),and fractionated chondrite-normalized LREE and nearly flat HREE patterns[(La/Yb)N=2.86-5.77;(Dy/Yb)N=1.21-1.49]with noticeable negative Nb and ta anomalies on the primitive mantle-normalized trace element ***ε(Nd)(t)values(-4.76 to+0.92)and high(206 Pb/204 Pb)i(18.40-18.66)along with partial melt modeling indicates that the basalts were likely derived from a sub-continental lithospheric mantle(SCLM)source metasomatized by subduction-related *** the basis of a similar emplacement age to the Panjal basalts and Qiangtang mafic dykes and flood basalts in the Himalayas,combined with a tectonic reconstruction of Gondwana in the Early Permian,we propose that the large-scale eruption of these basalts and dykes was related to an Early Permian mantle plume that possibly initiated the rifting on the northern margin of East Gondwana.

关键词： geochemistry flood basalts Early Permian Baoshan Gondwana

SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the tarim Large Igneous Province and Subducted Slab-Plume Interaction in Its Petrogenesis

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1651-1652页

作者： CAO jun Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology School of Earth Sciences East China University of Technology

Objective During the Permian, at least four mafic continental large igneous provinces （LIPs） were tbrmed in eastern Asia, i.e., the Siberian traps （-251 Ma）, Emeishan LIP （-260 Ma）, tarim LIP （-290-270 Ma） and Panjal traps （-290 Ma）（Shellnutt et al., 2015）. The Emeishan and tarim LIPs in China are both known for the presence of several magmatic Fe-Ti-V oxide deposits hosted in layered mafic- ultramafic intrusions. The origin of such magmatic Fe-Ti- V oxide deposits is enigmatic. One of the long-lasting debates is the mechanism by which large amounts of Fe-Ti oxides accumulated in the layered intrusions. Regardless of mechanism, there is still considerable debate regarding the mantle source compositions of the Fe-Ti-V oxide ore- bearing intrusions, in the tarim LIP, a giant Fe-Ti-V oxide deposit is hosted by the Piqiang layered intrusion at the northern margin of the tarim block. This intrusion consists mainly of gabbro and minor plagioclase-bearing clinopyroxenite and anorthosite （Fig. l a）. For this study we present new SHRIMP zircon U-Pb age and whole-rock geochemical data for the Piqiang layered gabbroic intrusion to evaluate the nature of its possible source compositions, which in turn aids in understanding the formation of the giant Fe-Ti-V oxide deposit in the plume- related LIPs.

关键词： SHRIMP Zircon U-Pb Age of the Piqiang Layered Intrusion in the tarim Large Igneous Province and Subducted Slab-Plume Interaction In ta Pb

基于DPFNN网络机载武器战备高温贮存环境预计

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环境技术 2024年第8期42卷 28-34页

作者：郝宇君蔡良续李贺张建军中国航空综合技术研究所北京100028

由于机载外挂武器战备贮存时存在复杂的传热关系,为克服传热传质方程建模过程中对物性参数要求较高、求解困难等缺陷,准确预测极限环境条件下某型导弹舱内高温极值,提出一种基于DPFNN神经网络的机载外挂高温预计方法。以某型导弹为研究... 详细信息

由于机载外挂武器战备贮存时存在复杂的传热关系,为克服传热传质方程建模过程中对物性参数要求较高、求解困难等缺陷,准确预测极限环境条件下某型导弹舱内高温极值,提出一种基于DPFNN神经网络的机载外挂高温预计方法。以某型导弹为研究对象,地表温度Te、大气温度ta、大气相对湿度h、太阳辐射强度G为输入,建立DPFNN过程神经网络结构,为提加快收敛速度,提出参数独立自适应学习率的梯度下降算法PALA,建立某型导弹地面挂机时舱内温度预测模型,对比DPFNN与ANN、多元线性回归MLRM方法的泛化能力。基于DPFNN的温度预测模型能够根据连续三日环境条件的变化确预测舱内温度变化,最大绝对误差仅1.17℃,具有较好的泛化能力。基于DPFNN的过程神经网络温度预计模型具备准确预计机载外挂温度的能力,该方法可用于机载外挂贮存温度预计工作,为确定机载外挂贮存温度环境适应性要求与试验验证条件提供参考。

关键词：过程神经网络机载外挂贮存环境温度预计

Refinement of Enhanced Speech Using Hybrid-Median Filter and Harmonic Regeneration Approach

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Journal of Electronic Science and Technology 2014年第3期12卷 293-298页

作者： Ching-ta Lu jun-Hong Shen Kun-Fu Tseng Chih-Tsung Chen Department of Information Communication Asia University Department of Biomedical Imaging and Radiological Science China Medical University Department of Multimedia and Game Science Asia-Pacific Institute of Creativity

This study proposes a post-processor to improve the harmonic structure of a vowel in an enhanced speech, enabling the speech quality to be improved. Initially, a speech enhancement algorithm is employed to reduce the background noise for a noisy speech. Hence the enhanced speech is post-processed by a hybrid-median filter to reduce the musical effect of residual noise. Since the harmonic spectra are impacted by background noise and a speech enhancement process, the quality of a vowel is deteriorated. A harmonic regenerated method is developed to improve the quality of post-processed speech. Experimental results show that the proposed method can improve the quality of post-processed speech by adequately regenerating harmonic spectra.

关键词： Harmonic regeneration hybrid-median filter noise reduction post-processing speech enhancement

压电材料修正后的H-R混合变分原理及其层合板的精确法

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工程力学 2005年第5期22卷 43-47页

作者：卿光辉邱家俊塔娜天津大学机械工程学院力学系天津300072

将三维弹性体的Hellinger-Reissner(H-R)混合变分原理引入到具有机-电耦合效应的压电材料静力学问题中,建立了压电材料修正后的H-R混合变分原理,通过变分运算和分部积分得到了压电材料的状态向量方程。给出了四边简支的压电材料层合板... 详细信息

将三维弹性体的Hellinger-Reissner(H-R)混合变分原理引入到具有机-电耦合效应的压电材料静力学问题中,建立了压电材料修正后的H-R混合变分原理,通过变分运算和分部积分得到了压电材料的状态向量方程。给出了四边简支的压电材料层合板静力学状态向量方程的精确求解方法,数值实例的结果证明了方法是正确性的。这里的理论和求解方法同样适应于纯弹性材料板和压电材料板混合的层合板静力学问题的分析。变分原理将有利于压电材料问题相应的半解析法或有限元法的推导。

关键词：弹性材料压电材料层合板修正后的H-R混合变分原理状态向量方程

荒漠草原生长季不同时间尺度水热通量变化特征及其影响因子

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农业工程学报 2024年第15期40卷 65-75页

作者：韩信张宝忠车政王军周青云韩娜娜天津农学院水利工程学院天津300392 中国水利水电科学研究院内蒙古阴山北麓草原生态水文国家野外科学观测研究站北京100038 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 中建六局水利水电建设集团有限公司天津300222 天津农学院-中国农业大学智慧水利研究中心天津300392

荒漠草原水热通量变化特征及其影响因素分析对提高区域水热交换规律认识和了解其在气候变化中的作用具有重要意义。该研究基于内蒙古荒漠草原2018和2019年4—10月涡度相关系统与相应的环境因子观测资料,分析了荒漠草原不同时间尺度水热... 详细信息

荒漠草原水热通量变化特征及其影响因素分析对提高区域水热交换规律认识和了解其在气候变化中的作用具有重要意义。该研究基于内蒙古荒漠草原2018和2019年4—10月涡度相关系统与相应的环境因子观测资料,分析了荒漠草原不同时间尺度水热通量(感热通量(sensible heat flux,H)和潜热通量(latent heat flux,LE))及能量占比(H/LE)的变化特征及其环境因子调控机制。结果表明:1)H为该生态系统的主要能量消耗形式,且同一环境因子在不同生育期对H、LE、H/LE的影响存在差异;2)小时尺度上,H、LE呈单峰型变化,峰值均主要出现在12:00—14:00之间,且LE峰值出现时间较H滞后1~2 h。H的主要影响因素为平均风速(wind speed,Ws),相对湿度(relative humidity,RH)、饱和水汽压差(vaporpressuredeficit,VPD)和空气温度(airtemperature,ta),相关系数(correlation coefficient,r)绝对值大小分别为Ws(0.72)>RH(0.66)>VPD(0.61)>ta(0.38)。LE的主要影响因素为ta、VPD、地面温度(soil temperature,Ts)和降雨(precipitation,P);3)日尺度上,H、LE呈明显的季节变化,H的主要影响因素是RH、Ws、Ts、ta、P和VPD,LE主要影响因素为RH、Ws、Ts和ta;4)月尺度上,H、LE近似呈单峰型变化,夏季能量消散方式以LE为主,H的主要影响因素为RH、Ws和VPD,其中VPD正效应最强(r=0.75),P对LE的正效应最强(r=0.75),而RH对H/LE的负效应最强(r=-0.76)。研究结果有利于准确理解多时间尺度下荒漠草原H和LE对环境因子的响应,同时可为草原生态功能区的植被恢复、生态环境保护提供理论依据和技术支撑。

关键词：荒漠草原不同时间尺度水热通量影响因子

塔里木大火成岩省二叠纪碱性煌斑岩的岩石成因和深部地球动力学过程

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地球科学 2024年第7期49卷 2448-2474页

作者：曹俊陈苗苗万淑敏王慧丽易辉雷恒聪东华理工大学核资源与环境省部共建国家重点实验室江西南昌330013 中南大学有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 东华理工大学地球科学学院江西南昌330013

二叠纪塔里木大火成岩省以岩浆活动持续时间长、岩石类型复杂、巨量富铁碱性玄武岩为特征而区别于世界上其他以拉斑玄武岩为主体的大火成岩省,关于其地幔源区组分特征和成因仍然存在争议.选择塔里木大火成岩省西北缘瓦吉里塔格碱性煌斑... 详细信息

二叠纪塔里木大火成岩省以岩浆活动持续时间长、岩石类型复杂、巨量富铁碱性玄武岩为特征而区别于世界上其他以拉斑玄武岩为主体的大火成岩省,关于其地幔源区组分特征和成因仍然存在争议.选择塔里木大火成岩省西北缘瓦吉里塔格碱性煌斑岩岩脉为研究对象,通过锆石LA-ICP-MS U-Pb定年厘定这些碱性煌斑岩岩浆活动时间,并利用全岩主微量元素和Sr-Nd-Pb-Mg同位素以及单矿物成分分析,揭示其成因和塔里木大火成岩省形成的深部地球动力学过程.锆石LA-ICP-MS U-Pb定年结果限定了瓦吉里塔格碱性煌斑岩侵位年龄为279±1 Ma,属于塔里木大火成岩省第二期岩浆活动的产物.这些煌斑岩呈典型斑状全自形结构,斑晶矿物有橄榄石、单斜辉石、角闪石和黑云母,基质主要由斜长石、单斜辉石、角闪石、黑云母和钛磁铁矿等微晶组成.瓦吉里塔格碱性煌斑岩具有低SiO_(2)(43.5%~49.4%),高Fe_(2)O_(3)t(9.32%~15.50%)、TiO_(2)(2.28%~4.58%),Mg^(#)值在43.6~52.9,富集地幔相容元素(Ni、Cr)的特征,同时高Na_(2)O(2.58%~5.50%)和低K_(2)O/Na_(2)O比值(0.31~0.78)则反映了钠质岩石的属性.在微量元素上富集轻稀土元素、大离子亲石元素和高场强元素,具有弱的Nb-ta正异常以及K、Sr、Ti、Zr-Hf负异常.它们的(^(87)Sr/^(86)Sr)_(i)变化于0.70436~0.70534之间,ε_(Nd)(t)值变化于-1.88~+1.10之间,(^(206)Pb/^(204)Pb)_(i)值为17.19~17.89.其元素和Sr-Nd-Pb同位素地球化学特征与常见的OIB型碱性玄武岩相似,但却具有比正常玄武岩更轻的Mg同位素组成(δ^(26)Mg=-0.78‰~-0.57‰).瓦吉里塔格碱性煌斑岩的原始岩浆应是含碳酸盐化榴辉岩的地幔柱低程度部分熔融的产物,并且部分发生了地幔柱-岩石圈地幔相互作用.地幔柱-俯冲蚀变洋壳相互作用是控制塔里木大火成岩省复杂岩石组合的关键因素.

关键词：碱性煌斑岩 Mg同位素塔里木大火成岩省地幔柱俯冲蚀变洋壳岩石学

Petrogenesis and Metallogenesis of the Mazaertag Layered Intrusion in the tarim Large Igneous Province,NW China

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1653-1679页

作者： CAO jun WANG Qimeng Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of Technology Nanchang 330013 Jiangxi China School of Earth Sciences East China University of Technology Nanchang 330013 Jiangxi China NO.1 Institute of Geology and Mineral Resources Survey of Henan Luoyang 471023 Henan China

The Mazaertag layered intrusion is located in the northwestern part of the tarim large igneous province where several early Permian layered mafic-ultramafic intrusions host important Fe-Ti oxide deposits. The intrusion covers an area of -0.13 km-2 and has a vertical stratigraphic thickness of at least300 m. It consists chiefly of olivine clinopyroxenite, and is cut through by the nearby mafic-ultramafic dykes. In this paper, we report new mineral chemistry data and whole-rock chemical and isotopic compositions for the Mazaertag intrusion along with whole-rock isotopic compositions for the nearby mafic dykes. The averaged compositions of cumulus olivine, clinopyroxene and intercumulus plagioclase within individual samples range from Fo71-73,Mg^# = 76 to 79 and An65-75 but they do not define sustained reversals. The observed mineral compositions are consistent with the differentiation of a single batch of magma in a closed system. Rocks of the Mazaertag intrusion are characterized by enrichment in light REE relative to heavy REE, positive Nb and ta anomalies and a small range of age-corrected εNd（t）（-0.1 to ＋0.9） and initial ^87Sr/^86Sr values（0.7044 to 0.7068）. The slightly lower εNdt）, initial ^206Pb/^204Pb and higher initial ^87Sr/^86Sr values of the intrusion compared to those of the least contaminated dykes[εNdt） =＋2.8 to ＋3.4;^206Pb/^204Pb）i = 18.516-18.521;（^87Sr/^86Sr）i = 0.7038-0.7041] imply that the Mazaertag magma was subjected to small to modest degrees of contamination by the upper crust. The Sr-Nd isotopic compositions of the least contaminated dykes are consistent with derivation from a FOZO-like mantle source. The parental magma of the Mazaertag intrusion, estimated from clinopyroxene compositions using mineral-melt partition coefficients, has trace element compositions similar to some of the most primitive mafic dykes in the same area. This suggests that the Mazaertag intrusion and mafic dykes shared a similar mantle source. Therefore, the parental ma

关键词： clinopyroxene Fe-Ti oxide layered intrusion Mazaertag tarim large igneous province