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Variable Coefficient KdV Equation for Amplitude of Nonlinear Solitary Rossby Waves in a Sort of Time-Dependent Zonal Flow

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高原气象 2011年第2期30卷 349-354页

作者： da chao-jiu SUN Shu-peng SONG Jian YANG Lian-gui College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China School of Mathematics and Computer Science Institute Northwest University for Nationalities Lanahou 730124 China College of Science Inner Mongolia University of Technology Hohhot 010062 China School of Mathematical Sciences Inner Mongolia University Hohhot 010021 China)

On the basis of the quasi-geostrophic vorticity equation,theoretical research has been down upon the evolution of the amplitude of solitary Rossby waves employing the perturbation method,and come to the conclusion tha... 详细信息

关键词： Nonlinear Rossby Waves Variable coefficient KdV equation Time-dependent zonal flow Perturbation method

mKdV Equation for the Amplitude of Solitary Rossby Waves in Stratified Shear Flows with a Zonal Shear Flow

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Atmospheric and Oceanic Science Letters 2009年第1期2卷 18-23页

作者： Song Jian Yang Lian-Gui da chao-jiu Zhang Hui-Qin College of Mathematical Sciences Inner Mongolia UniversityHohhot 010021China College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Institute of Mechanics Chinese Academy of SciencesBeijing 100080China

In this paper,modified Korteweg-de Vries (mKdV) equations for the amplitude of solitary Rossby waves in stratified fluids with a zonal shear flow are derived by using a weakly nonlinear *** is found that the coefficients of mKdV equations depend not only on the β effect and the Visl-Brunt frequency,but also on the basic shear flow.

关键词： mKdV equation β effect shear flow Vaisala-Brunt frequency

缓变地形下Rossby波振幅演变满足的带有强迫项的KdV方程

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物理学报 2008年第4期57卷 2595-2599页

作者：达朝究丑纪范兰州大学大气科学学院

运用非线性方法与摄动法,讨论了当地形随时间缓变时Rossby波振幅的演变问题.从均值流体准地转涡度方程推导,得到Rossby波振幅演变满足带有强迫项的KdV方程的结论,而地形随时间的缓慢变化诱导了该方程的强迫项.

关键词：非线性Rossby波带有强迫项的KdV方程摄动法缓变地形

Elastic three-dimensional phononic topological insulators with Dirac hierarchy

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 54-62页

作者： Shao-Yong Huo Qiu-Shuang Yang jiu-jiu Chen Hong-Kang Li Long-chao Yao Fu-Chun He Chun-Ming Fu College of Mechanical Engineering University of South ChinaHengyang 421001China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

Three-dimensional(3D)phononic topological insulators(TIs)featuring two-dimensional(2D)surface states and one-dimensional(1D)hinge states have opened up a new route for multi-dimensional robust wave transport,providing unprecedented methods for integrated acoustic sensors and energy harvesting ***,aiming at the elastic 3D phononic TI with gapless surface states and hinge states,the realization of elastic 3D phononic TIs with gapless surface states and hinge states is a significant challenge due to the complicated multi-mode polarization of elastic waves in 3D *** this study,we demonstrate an elastic 3D phononic TI with a Dirac hierarchy by elaborately operating the corresponding spatial symmetries of the chiral honeycomb ***,a 3D double Dirac cone of elastic wave can be achieved by doubling the lattice along the outof-plane direction to fold two iso-frequency Weyl *** topological phase transitions and 2D gapless two-fold Dirac surface states of elastic wave are realized by breaking the half-lattice spatial translation ***,based on the Brillouin zone folding along the in-plane direction,the 2D gapless two-fold surface Dirac cones are folded into four-fold surface Dirac ***,by inducing the relative radius of adjacent holes to break the in-plane spatial inversion symmetry,the fourfold surface Dirac cones are gapped and associated with a surface state inversion,in which the gapless 1D hinge Dirac dispersion is *** research offers a route for engineering the hierarchies of TIs in 3D elastic wave systems and provides new possibilities for designing 3D ultrasonic devices with unconventional functions.

关键词： Dirac topological hierarchy

Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： jiu-Qiang Yang Nian-Tian Lin Kai Zhang Yan Cui chao Fu Dong Zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

Nehari流形在一类半线性抛物方程爆破中的应用

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山东大学学报（理学版） 2016年第1期51卷 123-127页

作者：刘洋达朝究李富明西北民族大学数学与计算机科学学院甘肃兰州730124

研究了一类半线性抛物方程的初边值问题,在具有正初始能量的情况下,通过Nehari流形与凸性方法得到了解的有限时间爆破,进而刻画了初始能量与有限时间爆破的关系。

关键词：半线性抛物方程有限时间爆破 Nehari流形

Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction

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Journal of Energy Chemistry 2024年第4期91卷 475-483页

作者： Xiao-Chen Sun Xing-Chi Li Ze-Wei Xie Chen-Yue Yuan De-jiu Wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-chao Liu Ya-Wen Zhang Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing National Laboratory for Molecular Sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported ***,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)*** obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 *** on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction *** Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,*** collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported *** study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions.

关键词： Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction

基于Lorenz系统的数值天气转折期预报理论探索

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物理学报 2014年第2期63卷 438-451页

作者：达朝究穆帅马德山于海鹏侯威龚志强西北民族大学数学与计算机科学学院兰州730030 兰州大学大气科学学院兰州730000 国家气候中心气候研究开放实验室北京100081

以Lorenz系统为研究对象,对数值天气转折期预报中的动力学特征进行了理论研究,通过对Lorenz系统平衡点稳定性的讨论,得到了区分准稳定区域和准不稳定区域的分界曲面,由此标定出准稳定区域和准不稳定区域.在准稳定区域,Lorenz曲线保持相... 详细信息

以Lorenz系统为研究对象,对数值天气转折期预报中的动力学特征进行了理论研究,通过对Lorenz系统平衡点稳定性的讨论,得到了区分准稳定区域和准不稳定区域的分界曲面,由此标定出准稳定区域和准不稳定区域.在准稳定区域,Lorenz曲线保持相对稳定,能够在该平衡点周围周期运动;在准不稳定区域,Lorenz曲线可能会从这个平衡点周围跃过分界曲面而进入另外一个平衡点周围,即发生突变,这是Lorenz系统的一个重要动力学特征;对数值天气转折期预报与气候突变检测、预测给出一种新理论和新方法.

关键词： Lorenz系统准稳定区域准不稳定区域气候突变

超临界二氧化碳在螺杆挤出过程中塑化混合酯发射药的研究:在线流变仪设计与实验测量

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火炸药学报 2024年第2期47卷 188-196,I0004页

作者：顾晗应三九胡启鹏汪超南京理工大学化学与化工学院江苏南京210094 教育部特种能源材料重点实验室江苏南京210094

为了改善混合酯发射药的加工流动性,在其挤出过程中注入超临界二氧化碳(SC-CO_(2))作为增塑剂;为了更好地研究塑化过程,设计制造了一个在线狭缝流变仪用来测量混合酯发射药的剪切黏度和流变参数。流动曲线表明,混合酯发射药和SC-CO_(2)... 详细信息

为了改善混合酯发射药的加工流动性,在其挤出过程中注入超临界二氧化碳(SC-CO_(2))作为增塑剂;为了更好地研究塑化过程,设计制造了一个在线狭缝流变仪用来测量混合酯发射药的剪切黏度和流变参数。流动曲线表明,混合酯发射药和SC-CO_(2)/发射药混合物都是非牛顿假塑性流体,幂律模型可以用来描述SC-CO_(2)/发射药混合物的流变行为。实验研究了剪切黏度随加工温度和增塑剂含量的变化规律,结果显示较高的加工温度有利于降低剪切黏度。在注入SC-CO_(2)后,黏流活化能降低了约20 kJ/mol。SC-CO_(2)被证明是一种有效的增塑剂,可以显著改善混合酯发射药的流动性。并且随着SC-CO_(2)含量的增加,挤出过程中的流动性会更好,但增塑剂含量的不断增加并不能无限制地提升塑化效果。

关键词：物理化学混合酯发射药超临界二氧化碳流变仪塑化增塑剂