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Surface Processes Driving Intracontinental Basin Subsidence in the Context of India–Eurasia Collision:Evidence from Flexural Subsidence Modeling of the Cenozoic Southern Tarim Basin along the West Kunlun Foreland,NW Tibetan Plateau
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作者 HUANG Hao LIN Xiubin +4 位作者 AN Kaixuan ZHANG Yuqing CHEN Hanlin CHENG Xiaogan LI Chunyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1778-1786,共9页
The India–Eurasia collision has produced a number of Cenozoic deep intracontinental basins,which bear important information for revealing the far-afield responses to the remote collision.Despite their significance,th... The India–Eurasia collision has produced a number of Cenozoic deep intracontinental basins,which bear important information for revealing the far-afield responses to the remote collision.Despite their significance,their subsiding mechanism remains the subject of debate,with end-member models attributing it to either orogenic or sedimentary load.In this study,we conduct flexural subsidence modeling with a two-dimensional finite elastic plate model on the Hotan-Mazatagh section along the southern Tarim Basin,which defines a key region in the foreland of the West Kunlun Orogen,along the NW margin of the Tibetan Plateau.The modeling results indicate that the orogenic load of West Kunlun triggers the southern Tarim Basin to subside by up to less than ~6 km,with its impact weakening towards the basin interiors until ~230 km north from the Karakax fault.The sedimentary load,consisting of Cenozoic strata,forces the basin to subside by ~2 to~7 km.In combination with the retreat of the proto-Paratethys Sea and the paleogeographic reorganization of the Tarim Basin,we propose that surface processes,in particular a shift from an exorheic to an endorheic drainage system associated with the consequent thick sedimentary load,played a decisive role in forming deep intracontinental basins in the context of the India-Eurasia collision. 展开更多
关键词 flexural subsidence modeling India-Eurasia collision West Kunlun Tarim Basin Northwest Tibetan plateau
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Displacement Field Variable Modeling Method for Heterogeneous Materials in Wind Power Blade Core Plates
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作者 Ying He Yongshuang Wen +3 位作者 Xuemei Huang Leian Zhang Rujun Song Chang Li 《Energy Engineering》 EI 2023年第2期445-459,共15页
In order to study the mechanical properties of the heterogeneous core plate of the wind turbine blade,a modeling method of the core plate based on displacement field variables is proposed.Firstly,the wind turbine blad... In order to study the mechanical properties of the heterogeneous core plate of the wind turbine blade,a modeling method of the core plate based on displacement field variables is proposed.Firstly,the wind turbine blade core plate was modeled according to the theory of modeling heterogeneous material characteristics.Secondly,the three-point bending finite element model of the wind turbine blade core plate was solved by the display dynamic equation to obtain the deformation pattern and force-deformation relationship of the core plate.Finally,the three-point bending static test was conducted to compare with the finite element analysis.The test results show that:the damage form of the wind turbine blade core plate includes elasticity,yield,and failure stages.The main failure modes are plastic deformation,core material collapse,and panel-core delamination.The failure load measured by the test is 1.59 kN,which is basically consistent with the load-displacement result obtained by the simulation,with a difference of only 1.9%,which verifies the validity and reliability of the model.It provides data references for wind turbine blade structure design. 展开更多
关键词 Blade core plate heterogeneous material modeling method finite element analysis PVC material
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FINITE ELEMENT MODELING OF MODERATELY THICK COMPOSITE PLATE WITH PIEZOELECTRIC SENSORS AND ACTUATORS 被引量:2
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作者 周勇 王鑫伟 谈梅兰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期205-210,共6页
A rectangular finite element for laminated plate with bonded and/or embedded piezoelectric sensors and actuators is developed based on the variational principle and the first order shear deformation theory. The elemen... A rectangular finite element for laminated plate with bonded and/or embedded piezoelectric sensors and actuators is developed based on the variational principle and the first order shear deformation theory. The element has four-node, 20-degrees-of-freedom with one potential degree of freedom for each piezoelectric layer to represent the piezoelectric behavior. The higher order derivation of deflection is obtained by using the normal rotation expressions to take the effects of transverse shear deformation into considerations. The finite element can accurately simulate the deformation of both thin and moderately thick plates. A Fortran program is written and a number of benchmark tests are exercised to verify its effectiveness. Results are compared well with the existing data. The unbalanced composite with piezoelectric layers is then analyzed by using the model. Results show that the changes of the ratio between the thickness of positive angle layers and the negative angle layers have an effect on the deformation of the structure under the same electric loading. 展开更多
关键词 finite element COMPOSITE moderately thick plate PIEZOELECTRIC ACTUATOR SENSOR
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Human induced dryland degradation in Ordos Plateau,China,revealed by multilevel statistical modeling of normalized difference vegetation index and rainfall time-series 被引量:16
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作者 Jing ZHANG JianMing NIU +4 位作者 Tongliga BAO Alexander BUYANTUYEV Qing ZHANG JianJun DONG XueFeng ZHANG 《Journal of Arid Land》 SCIE CSCD 2014年第2期219-229,共11页
Land degradation causes serious environmental problems in many regions of the world, and although it can be effectively assessed and monitored using a time series of rainfall and a normalized difference vegetation ind... Land degradation causes serious environmental problems in many regions of the world, and although it can be effectively assessed and monitored using a time series of rainfall and a normalized difference vegetation index (NDVI) from remotely-sensed imagery, dividing human-induced land degradation from vegetation dynamics due to climate change is not a trivial task. This paper presented a multilevel statistical modeling of the NDVI-rainfall relationship to detect human-induced land degradation at local and landscape scales in the Ordos Plateau of Inner Mongolia, China, and recognized that anthropogenic activities result in either positive (land restoration and re-vegetation) or negative (degradation) trends. Linear regressions were used to assess the accuracy of the multi- level statistical model. The results show that: (1) land restoration was the dominant process in the Ordos Plateau between 1998 and 2012; (2) the effect of the statistical removal of precipitation revealed areas of human-induced land degradation and improvement, the latter reflecting successful restoration projects and changes in land man- agement in many parts of the Ordos; (3) compared to a simple linear regression, multilevel statistical modeling could be used to analyze the relationship between the NDVI and rainfall and improve the accuracy of detecting the effect of human activities. Additional factors should be included when analyzing the NDVI-rainfall relationship and detecting human-induced loss of vegetation cover in drylands to improve the accuracy of the approach and elimi- nate some observed non-significant residual trends. 展开更多
关键词 NDVl-rainfall relationship anthropogenic activities multilevel statistical modeling land degradation DRYLAND Ordos plateau
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Modeling Geometrically Nonlinear FG Plates: A Fast and Accurate Alternative to IGA Method Based on Deep Learning
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作者 Se Li Tiantang Yu Tinh Quoc Bui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2793-2808,共16页
Isogeometric analysis (IGA) is known to showadvanced features compared to traditional finite element approaches.Using IGA one may accurately obtain the geometrically nonlinear bending behavior of plates with functiona... Isogeometric analysis (IGA) is known to showadvanced features compared to traditional finite element approaches.Using IGA one may accurately obtain the geometrically nonlinear bending behavior of plates with functionalgrading (FG). However, the procedure is usually complex and often is time-consuming. We thus put forward adeep learning method to model the geometrically nonlinear bending behavior of FG plates, bypassing the complexIGA simulation process. A long bidirectional short-term memory (BLSTM) recurrent neural network is trainedusing the load and gradient index as inputs and the displacement responses as outputs. The nonlinear relationshipbetween the outputs and the inputs is constructed usingmachine learning so that the displacements can be directlyestimated by the deep learning network. To provide enough training data, we use S-FSDT Von-Karman IGA andobtain the displacement responses for different loads and gradient indexes. Results show that the recognition erroris low, and demonstrate the feasibility of deep learning technique as a fast and accurate alternative to IGA formodeling the geometrically nonlinear bending behavior of FG plates. 展开更多
关键词 FG plates geometric nonlinearity deep learning BLSTM IGA S-FSDT
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Ultimate Compressive Strength Computational Modeling for Stiffened Plate Panels with Nonuniform Thickness 被引量:1
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作者 Hyun Ho Lee Jeom Kee Paik 《Journal of Marine Science and Application》 CSCD 2020年第4期658-673,共16页
The aim of this paper is to develop computational models for the ultimate compressive strength analysis of stiffened plate panels with nonuniform thickness.Modeling welding-induced initial deformations and residual st... The aim of this paper is to develop computational models for the ultimate compressive strength analysis of stiffened plate panels with nonuniform thickness.Modeling welding-induced initial deformations and residual stresses was presented with the measured data.Three methods,i.e.,ANSYS finite element method,ALPS/SPINE incremental Galerkin method,and ALPS/ULSAP analytical method,were employed together with existing test database obtained from a full-scale collapse testing of steel-stiffened plate structures.Sensitivity study was conducted with varying the difference in plate thickness to define a representative(equivalent)thickness for plate panels with nonuniform thickness.Guidelines are provided for structural modeling to compute the ultimate compressive strength of plate panels with variable thickness. 展开更多
关键词 Ultimate compressive strength Steel-stiffened plate structures Nonuniform plate thickness ANSYS finite element method ALPS/SPINE incremental Galerkin method ALPS/ULSAP analytical method
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Modeling and Analysis of Vibration Characteristics of Rectangular Plate with Circular Through Hole Under Complex Boundary Conditions
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作者 TANG Tianyi HE Yijie +3 位作者 WU Jiajun DONG Menglong WANG Gang NI Junfang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期515-525,共11页
This paper presents a method to study the free vibration of a plate with circular holes.The circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are zero.Therefore,the f... This paper presents a method to study the free vibration of a plate with circular holes.The circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are zero.Therefore,the free vibration problem of the circular hole plate can be transformed into the free vibration problem of the equivalent rectangular plate with non-uniform thickness.The model is derived from the spectral geometry method(SGM),and the displacement of the plate with circular holes is expanded by the modified Fourier series.Virtual springs are added to the boundary of the plate to simulate the boundary conditions of simply supported and fixed supports.The accuracy of this method is verified by comparison with the finite element calculation results.The relationship between modal numerical solutions of plates with circular holes and boundary conditions and geometry of the plate is studied. 展开更多
关键词 round hole plate spectral geometry method(SGM) energy method virtual spring
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A GIS-based Modeling Approach for Fast Assessment of Soil Erosion by Water at Regional Scale, Loess Plateau of China 被引量:2
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作者 HU Llangjun YANG Haijun +1 位作者 YANG Qinke LI Rui 《Chinese Geographical Science》 SCIE CSCD 2010年第5期423-433,共11页
The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of bo... The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of both regional patterns of soil loss and its impact factors in the plateau area. Based on the regional characteristics of precipitation, vegetation and land form, and with the use of Landsat TM and ground investigation data, the entire Loess Plateau was first divided into 3 380 Fundamental Assessment Units (FAUs) to adapt to this regional modeling and fast assessment. A set of easily available parameters reflecting relevant water erosion factors at a regional scale was then developed, in which dynamic and static factors were discriminated. Arclnfo GIS was used to integrate all essential data into a central database. A resulting mathematical model was established to link the sediment yields and the selected variables on the basis of FAUs through overlay in GIS and multiple regression analyses. The sensitivity analyses and validation results show that this approach works effectively in assessing large area soil erosion, and also helps to understand the regional associations of erosion and its impact factors, and thus might significantly contribute to planning and policymaking for a large area erosion control in the Loess Plateau. 展开更多
关键词 soil erosion by water G/S-based modeling soil erosion assessment regional scale Loess plateau
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Modeling of Total Dissolved Solids (TDS) and Sodium Absorption Ratio (SAR) in the Edwards-Trinity Plateau and Ogallala Aquifers in the Midland-Odessa Region Using Random Forest Regression and eXtreme Gradient Boosting
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作者 Azuka I. Udeh Osayamen J. Imarhiagbe Erepamo J. Omietimi 《Journal of Geoscience and Environment Protection》 2024年第5期218-241,共24页
Efficient water quality monitoring and ensuring the safety of drinking water by government agencies in areas where the resource is constantly depleted due to anthropogenic or natural factors cannot be overemphasized. ... Efficient water quality monitoring and ensuring the safety of drinking water by government agencies in areas where the resource is constantly depleted due to anthropogenic or natural factors cannot be overemphasized. The above statement holds for West Texas, Midland, and Odessa Precisely. Two machine learning regression algorithms (Random Forest and XGBoost) were employed to develop models for the prediction of total dissolved solids (TDS) and sodium absorption ratio (SAR) for efficient water quality monitoring of two vital aquifers: Edward-Trinity (plateau), and Ogallala aquifers. These two aquifers have contributed immensely to providing water for different uses ranging from domestic, agricultural, industrial, etc. The data was obtained from the Texas Water Development Board (TWDB). The XGBoost and Random Forest models used in this study gave an accurate prediction of observed data (TDS and SAR) for both the Edward-Trinity (plateau) and Ogallala aquifers with the R<sup>2</sup> values consistently greater than 0.83. The Random Forest model gave a better prediction of TDS and SAR concentration with an average R, MAE, RMSE and MSE of 0.977, 0.015, 0.029 and 0.00, respectively. For the XGBoost, an average R, MAE, RMSE, and MSE of 0.953, 0.016, 0.037 and 0.00, respectively, were achieved. The overall performance of the models produced was impressive. From this study, we can clearly understand that Random Forest and XGBoost are appropriate for water quality prediction and monitoring in an area of high hydrocarbon activities like Midland and Odessa and West Texas at large. 展开更多
关键词 Water Quality Prediction Predictive modeling Aquifers Machine Learning Regression eXtreme Gradient Boosting
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Analytical Modeling of Vibration of Micropolar Plates 被引量:1
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作者 Lev Steinberg Roman Kvasov 《Applied Mathematics》 2015年第5期817-836,共20页
This paper presents an extension of mathematical static model to dynamic problems of micropolar elastic plates, recently developed by the authors. The dynamic model is based on the generalization of Hellinger-Prange-R... This paper presents an extension of mathematical static model to dynamic problems of micropolar elastic plates, recently developed by the authors. The dynamic model is based on the generalization of Hellinger-Prange-Reissner (HPR) variational principle for the linearized micropolar (Cosserat) elastodynamics. The vibration model incorporates high accuracy assumptions of the micropolar plate deformation. The computations predict additional natural frequencies, related with the material microstructure. These results are consistent with the size-effect principle known from the micropolar plate deformation. The classic Mindlin-Reissner plate resonance frequencies appear as a limiting case for homogeneous materials with no microstructure. 展开更多
关键词 COSSERAT Materials plate VIBRATION Frequencies of TRANSVERSE MICRO-VIBRATION VARIATIONAL Principle
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Mountain permafrost distribution modeling using Multivariate Adaptive Regression Spline (MARS) in the Wenquan area over the Qinghai-Tibet Plateau 被引量:3
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作者 XiuMin Zhang ZhuoTong Nan +3 位作者 JiChun Wu ErJi Du Tong Wang YanHui You 《Research in Cold and Arid Regions》 2012年第5期361-370,共10页
In high mountainous areas, the development and distribution of alpine permafrost is greatly affected by macro- and mi- cro-topographic factors. The effects of latitude, altitude, slope, and aspect on the distribution ... In high mountainous areas, the development and distribution of alpine permafrost is greatly affected by macro- and mi- cro-topographic factors. The effects of latitude, altitude, slope, and aspect on the distribution of permafrost were studied to under- stand the dislribution patterns of permafrost in Wenquan on the Qinghai-Tibet Plateau. Cluster and correlation analysis were per- formed based on 30 m Global Digital Elevation Model (GDEM) data and field data obtained using geophysical exploration and borehole drilling methods. A Multivariate Adaptive Regression Spline model (MARS) was developed to simulate permafrost spa- tial distribution over the studied area. A validation was followed by comparing to 201 geophysical exploration sites, as well as by comparing to two other models, i.e., a binary logistic regression model and the Mean Annual Ground Temperature model (IVlAGT). The MARS model provides a better simulation than the other two models. Besides the control effect of elevation on permafrost distribution, the MARS model also takes into account the impact of direct solar radiation on permafrost distribution. 展开更多
关键词 permafrost distribution model Multivariate Adaptive Regression Splines Qinghai-Tibet plateau PERMAFROST
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Optimization and kinetic modeling of waste lard methanolysis in a continuous reciprocating plate reactor 被引量:1
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作者 Marija R.Miladinovic Ivan J.Stojkovic +3 位作者 Ana V.Velickovic Olivera S.Stamenkovic Ivana B.Bankovic-Ilic Vlada B.Veljkovic 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2481-2490,共10页
Continuous biodiesel production from a waste pig-roasting lard,methanol and KOH was carried out in a reciprocating plate reactor(RPR)using a factorial design containing three process factors,namely methanol/lard molar... Continuous biodiesel production from a waste pig-roasting lard,methanol and KOH was carried out in a reciprocating plate reactor(RPR)using a factorial design containing three process factors,namely methanol/lard molar ratio,catalyst loading,and normalized height of the reactor.The main goals were to optimize the influential process factors with respect to biodiesel purity using the response surface methodology and to model the kinetics of the transesterification reaction in order to describe the change of triacylglycerols(TAG)and fatty acid methyl esters(FAME)concentrations along the RPR height.The first-order rate law was proved for both the reaction and the mass transfer.The model of the changing reaction mechanism and mass transfer of TAG was also applicable.Both kinetic models agreed with the experimental concentrations of TAG and FAME determined along the RPR height. 展开更多
关键词 Biodiesel Kinetics OPTIMIZATION Reciprocating plate reactor Waste lard
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Thermal modeling and the optimized design of metal plate cooling systems for single concentrator solar cells
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作者 崔敏 陈诺夫 邓金祥 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期283-288,共6页
A metal plate cooling model for 400~ single concentrator solar cells was established. The effects of the thickness and the radius of the metal plate, and the air environment on the temperature of the solar cells were ... A metal plate cooling model for 400~ single concentrator solar cells was established. The effects of the thickness and the radius of the metal plate, and the air environment on the temperature of the solar cells were analyzed in detail. It is shown that the temperature of the solar cells decreased sharply at the beginning, with the increase in the thickness of the metal plate, and then changed more smoothly. When the radius of the metal plate was 4 cm and the thickness increased to 2 mm or thicker, the temperature of the solar cell basically stabilized at about 53℃. Increasing the radius of the metal plate and the convective transfer coefficient made the temperature of the solar cell decrease remarkably. The effects of A1 and Cu as the metal plate material on cooling were analyzed contrastively, and demonstrated the superiority of A1 material for the cooling system. Furthermore, considering cost reduction, space holding and the stress of the system, we optimized the structural design of the metal plate. The simulated results can be referred to the design of the structure for the metal plate. Finally, a method to devise the structure of the metal plate for single concentrator solar cells was given. 展开更多
关键词 metal plate modeling concentrator solar cells COOLING
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Electromagnetic Modeling of Metallic Elliptical Plates
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作者 Rizwan H. Alad S. B. Chakrabarty Karl E. Lonngren 《Journal of Electromagnetic Analysis and Applications》 2012年第11期468-473,共6页
This paper presents the evaluation of the capacitance of an isolated elliptical plate and two parallel elliptical plates. Integral equations are formed by relating the previously unknown charges on the elliptical plat... This paper presents the evaluation of the capacitance of an isolated elliptical plate and two parallel elliptical plates. Integral equations are formed by relating the previously unknown charges on the elliptical plates and the potential on the metallic plates. The integral equations are solved by applying the method of moments based on the pulse function and point matching. The elements of the matrix in the method of moments are found by dividing the structure into triangular subsections. The matrix equation is solved in order to compute the unknown charges on each subsection. Numerical results on the capacitance as a function of the geometrical parameters of the ellipse are presented. 展开更多
关键词 ELLIPTICAL METALLIC plate CAPACITANCE Pulse Function Point MATCHING
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A Dynamic Coupling of Ocean and Plate Motion
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作者 Yongfeng Yang 《International Journal of Geosciences》 CAS 2024年第9期737-763,共27页
Plate motion representing a remarkable Earth process is widely attributed to several primary forces such as ridge push and slab pull. Recently, we have presented that the ocean water pressure against the wall of conti... Plate motion representing a remarkable Earth process is widely attributed to several primary forces such as ridge push and slab pull. Recently, we have presented that the ocean water pressure against the wall of continents may generate enormous force on continents. Continents are physically fixed on the top of the lithosphere that has been already broken into individual plates, this attachment enables the force to be laterally transferred to the lithospheric plates. In this study, we combine the force and the existing plate driving forces (i.e., ridge push, slab pull, collisional, and shearing) to account for plate motion. We show that the modelled movements for the South American, African, North American, Eurasian, Australian, Pacific plates are well agreement with the observed movements in both speed and azimuth, with a Root Mean Square Error (RMSE) of the modelled speed against the observed speed of 0.91, 3.76, 2.77, 2.31, 7.43, and 1.95 mm/yr, respectively. 展开更多
关键词 Ocean Water Pressure Force Ocean-Continent Interaction plate Driving Force Lithospheric plate plate Motion
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Hydric Properties Evolution of <i>Spirulina platensis</i>during Drying: Experimental Analysis and Modeling
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作者 Eloi Salmwendé Tiendrebeogo Guy Christian Tubreoumya +5 位作者 A. O. Dissa A. Compaoré Jean Koulidiati F. Cherblanc J.-C. Bénet I. Youm 《Food and Nutrition Sciences》 2019年第6期561-577,共17页
Hydric properties evolution during drying differs from one product to another and has been the subject of various studies due to its crucial importance in modeling the drying process. The variation of these parameters... Hydric properties evolution during drying differs from one product to another and has been the subject of various studies due to its crucial importance in modeling the drying process. The variation of these parameters in the solid matrix and in time during the drying of Spirulina platensis has not known an advanced understanding. The objective of this study was to evaluate the evolution of the water content profile, the mass flow, the concentration gradient and the diffusion coefficient during the drying of Spirulina platensis taking into account the shrinkage. Modeling and experimental analysis (at 50°C and HR = 6%) by the cutting method a cylinder 20 mm in diameter and 40 mm thick were carried. The water content profiles of two different products grown in semi-industrial farms from Burkina Faso and France with initial water contents respectively of the range from 2.73 kgw/kgdb and 3.12 kgw/kgdb were determined. These profiles have been adjusted by a polynomial function. Identical water behavior is observed regardless of the origin of the samples. Water distribution is heterogeneous. Mass flow and concentration gradient are greater at the edge than inside the product. The water transport coefficient, ranging from 1.70 × 10?10 to 94 × 10?10 m2/s, is determined from a linear approach. 展开更多
关键词 DRYING Experiment modeling SPIRULINA plateNSIS Hydric PROPERTY
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Laminar Heat Transfer Modeling and Investigation of Thermal Dispersion in a Flat Plate Heat Exchanger: Estimating Heat Transfer Coefficient, Heat Flux and Nusselt Number
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作者 Saeedeh Imani Moqadam Mojtaba Mirdrikvand Behrooz Roozbehani Amirali Rezazadeh 《Journal of Chemistry and Chemical Engineering》 2012年第7期613-618,共6页
PHEs (plate heat exchangers) are among the most common thermal equipments in diverse industries particularly in oil and gas companies. This wide usage is obviously due to significant benefits of these heat exchanger... PHEs (plate heat exchangers) are among the most common thermal equipments in diverse industries particularly in oil and gas companies. This wide usage is obviously due to significant benefits of these heat exchangers over other types. In this article, a behavioral analysis of heat transfer in fiat plates of these heat exchangers in laminar flow situation through CFD (computational fluid dynamics) simulation using FLUENT 6.3.26 software is done. The study reveals results graphically based on fluid's behavior in co-current and counter current flows and discusses thermal indexes consisting of heat transfer coefficient, Nusslet and total heat flux in both conditions. Eventually, a comparison via the graphical results is presented between the two types of flow directions. 展开更多
关键词 Flat plate heat exchanger nusslet heat flux heat transfer coefficient FLUENT CFD.
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Influences of crustal thickening in the Tibetan Plateau on loading modeling and inversion associated with water storage variation
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作者 Wang Hansheng Xiang Longwei +4 位作者 Wu Patrick Jia Lulu Jiang Liming Shen Qiang Steffen Holger 《Geodesy and Geodynamics》 2015年第3期161-172,共12页
We use the average crustal structure of the CRUST1.0 model for the Tibetan Plateau to establish a realistic earth model termed as TC1 P, and data from the Global Land Data Assimilation System(GLDAS) hydrology model an... We use the average crustal structure of the CRUST1.0 model for the Tibetan Plateau to establish a realistic earth model termed as TC1 P, and data from the Global Land Data Assimilation System(GLDAS) hydrology model and Gravity Recovery and Climate Experiment(GRACE) data, to generate the hydrology signals assumed in this study. Modeling of surface radial displacements and gravity variation is performed using both TC1 P and the global Preliminary Reference Earth Model(PREM). Furthermore, inversions of the hydrology signals based on simulated Global Positioning System(GPS) and GRACE data are performed using PREM. Results show that crust in TC1 P is harder and softer than that in PREM above and below a depth of 15 km, respectively, causing larger differences in the computed load Love numbers and loading Green’s functions. When annual hydrology signals are assumed,the differences of the radial displacements are found to be as large as approximately0.6 mm for the truncated degree of 180; while for hydrology-trend signals the differences are very small. When annual hydrology signals and the trends are assumed, the differences in the surface gravity variation are very small. It is considered that TC1 P can be used to efficiently remove the hydrological effects on the monitoring of crustal movement. It was also found that when PREM is used inappropriately, the inversion of the hydrology signals from simulated annual GPS signals can only recover approximately 88.0% of the annual hydrology signals for the truncated degree of 180, and the inversion of hydrology signals from the simulated trend GPS signals can recover approximately 92.5% for the truncated degree of 90. However, when using the simulated GRACE data, it is possible to recover almost 100%. Therefore, in future, the TC1 P model can be used in the inversions ofhydrology signals based on GPS network data. PREM is also valid for use with inversions of hydrology signals from GRACE data at resolutions of approximately 220 km and larger. 展开更多
关键词 Tibetan plateau Earth model Water storage variatio
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Formation of the Tibetan Plateau during the India-Eurasia Convergence:Insight from 3-D Multi-Terrane Thermomechanical Modeling
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作者 Jile Chen Peimin Zhu +1 位作者 Yuefeng Yuan Guifan Chen 《Journal of Earth Science》 SCIE CAS CSCD 2024年第1期112-130,共19页
Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first tw... Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first two models are primarily constructed on pure mechanical models but are unable to reasonably explain the tension and shear phenomena inside the plateau.The latter two are rheological dynamic models based on deep geophysical observations.However,the spatial range of the lower crustal flow and its role in the plateau formation/uplift remain controversial.Five multi-terrane viscoplastic thermomechanical models were constructed to simulate the uplift and lithospheric structure change of the Tibetan Plateau during the post-collision stage(since 35 Ma)under the convergence of the Indian Plate.Results show that the plateau's formation begins with crustal thickening,blocked by strong terranes at the northern plateau,and expanded laterally to the east.The lithosphere thickens gradually and experiences delamination at its base,elevating temperature within the crust and forming partial melting layers in the central plateau.As convergence persists on the southern side,the northern plateau's lithosphere bends downward and undergoes delamination,further heating the crust and promoting the northward and eastward flow of partial melting layers,leading to secondary uplift around the plateau. 展开更多
关键词 3-D thermomechanical modeling Tibetan plateau plateau uplift crustal flow
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Dynamic Modeling and Analysis ofWind Turbine Blade of Piezoelectric Plate Shell
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作者 Yinhu Qiao Chunyan Zhang Jiang Han 《Sound & Vibration》 2019年第1期14-24,共11页
This paper presents a theoretical analysis of vibration control technology of wind turbine blades made of piezoelectric intelligent structures.The design of the blade structure,which is made from piezoelectric materia... This paper presents a theoretical analysis of vibration control technology of wind turbine blades made of piezoelectric intelligent structures.The design of the blade structure,which is made from piezoelectric material,is approximately equivalent to a flat shell structure.The differential equations of piezoelectric shallow shells for vibration control are derived based on piezoelectric laminated shell theory.On this basis,wind turbine blades are simplified as elastic piezoelectric laminated shells.We establish the electromechanical coupling system dynamic model of intelligent structures and the dynamic equation of composite piezoelectric flat shell structures by analyzing simulations of active vibration control.Simulation results show that,under wind load,blade vibration is reduced upon applying the control voltage. 展开更多
关键词 Wind-turbine blade smart structure laminated shallow shell dynamics modeling
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