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The Youth’s View of Marriage in Chinese Mainstream Media Discourse-A Corpus-assisted Three-dimensional Discourse Analysis
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作者 DING Shu-li LIN Ying 《Journal of Literature and Art Studies》 2024年第4期284-289,共6页
The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse an... The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse analysis model,this paper builds a“Chinese media News Report Corpus on the topic of‘marriage’”whose news are collected from China Daily.It is found that the discourses are neutral and objective with regard to the advantages and disadvantages of marriage,but in general,it is still a traditional view of marriage that is inevitable and closely related to fertility.Although this is controlled by the policies and the social reasons including declining fertility rate,it deviates from the current view of the youth towards marriage,resulting in many serious consequences such as young people’s rejection.In addition,this research found that male and female have great differences in their views on marriage,and men’s resistance to marriage is far greater than that of women,which is departure from the public’s cognition.The reasons behind this need to be explored in order to solve the marriage and love problems of young people in today’s era and realize the healthy development of young marriage. 展开更多
关键词 CORPORA three-dimensional discourse analysis the youth’view of marriage
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A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels
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作者 Shen Yan Dajiang Geng +2 位作者 Ning Dai Mingjian Long Zhicheng Bai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2893-2915,共23页
According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer.To address this challenge,a subterranean transfer str... According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer.To address this challenge,a subterranean transfer structure spanning multiple subway tunnels was proposed.Deliberating on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam model.The resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer structure.The research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent tunnels.The established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate action.The pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment. 展开更多
关键词 crossing tunnels transfer structure force mechanism simplify analysis layered soil mass
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Importance of Three-Dimensional Piezoelectric Coupling Modeling in Quantitative Analysis of Piezoelectric Actuators 被引量:1
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作者 Daisuke Ishihara Prakasha Chigahalli Ramegowda +1 位作者 Shoichi Aikawa Naoki Iwamaru 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1187-1206,共20页
This paper demonstrates the importance of three-dimensional(3-D)piezoelectric coupling in the electromechanical behavior of piezoelectric devices using three-dimensional finite element analyses based on weak and stron... This paper demonstrates the importance of three-dimensional(3-D)piezoelectric coupling in the electromechanical behavior of piezoelectric devices using three-dimensional finite element analyses based on weak and strong coupling models for a thin cantilevered piezoelectric bimorph actuator.It is found that there is a significant difference between the strong and weak coupling solutions given by coupling direct and inverse piezoelectric effects(i.e.,piezoelectric coupling effect).In addition,there is significant longitudinal bending caused by the constraint of the inverse piezoelectric effect in the width direction at the fixed end(i.e.,3-D effect).Hence,modeling of these effects or 3-D piezoelectric coupling modeling is an electromechanical basis for the piezoelectric devices,which contributes to the accurate prediction of their behavior. 展开更多
关键词 Piezoelectric coupling effect piezoelectric bimorph actuator weak coupling strong coupling three-dimensional finite element analysis
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Application of three-dimensional speckle tracking technique in measuring left ventricular myocardial function in patients with diabetes
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作者 Zheng Li Ying Qian +1 位作者 Chun-Yun Fan Yong Huang 《World Journal of Diabetes》 SCIE 2024年第4期783-792,共10页
BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use... BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use of the three-dimensional speckle tracking technique(3D-STI)for measuring LVSF in DM patients via meta-analysis.METHODS The electronic databases were retrieved from the initial accessible time to 29 April 2023.The current study involved 9 studies,including 970 subjects.We carried out this meta-analysis to estimate myocardial function in DM compared with controls according to myocardial strain attained by 3D-STI.RESULTS Night articles including 970 subjects were included.No significant difference was detected in the left ventricular ejection fraction between the control and the diabetic group(P>0.05),while differences in global longitudinal strain,global circumferential strain,global radial strain,and global area strain were markedly different between the controls and DM patients(all P<0.05).CONCLUSION The 3D-STI could be applied to accurately measure early LVSF damage in patients with DM. 展开更多
关键词 Diabetes mellitus Left ventricular systolic dysfunction three-dimensional speckle tracking echocardiography Meta analysis
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Discourse Analysis of the Belt and Road Initiative From the Perspective of Central Asian Countries: A Case Study of the Republic of Kazakhstan
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作者 CHEN Jia LIU Shumin +1 位作者 FU Da’an SHAO Di 《Journalism and Mass Communication》 2024年第2期96-100,共5页
This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initi... This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initiative(BRI)in Central Asian countries.Through detailed analysis of policy documents,media reports,and public discussions in Central Asian countries,this paper reveals how the BRI constructs specific social practices,discourse events,and textual meanings within these nations.The findings indicate that through this global development strategy,China has not only strengthened its economic ties with Central Asian countries but has also exerted profound influences on political,cultural,and social levels. 展开更多
关键词 Belt and Road Initiative Central Asian countries discourse analysis Norman Fairclough’s three-dimensional model
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Generalized response displacement methods for seismic analysis of underground structures with complex cross section
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作者 Xu Zigang Ding Linling +2 位作者 Du Xiuli Xu Chengshun Zhuang Haiyang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期979-993,共15页
The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing ... The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing geotechnical works(ISO 23469)and code for seismic design of urban rail transit structures(GB 50909-2014).However,there are some obvious limitations in the application of RDM.Springs and the shear stress of the soil could be approximately evaluated for the structures having a simple cross section,such as rectangular and circular structures.It is necessary to propose simplified seismic analysis methods for structures with complex cross sections.This paper refers to the idea of RDM and proposes three generalized response displacement methods(GRDM).In GRDM1,a part of the soil surrounding a structure is selected to generate a generalized underground structure with a rectangular cross section,and the same analysis model as RDM is applied to analyze the responses of the structure.In GRDM2,a hollow soil model without a generalized structure is used to compute the equivalent load caused by the relative displacement of the soil,and the soil-structure interaction model is applied to calculate the responses of the structure.In GRDM3,a continuous soil model is applied to compute the equivalent load caused by the relative displacement and shear stress of the soil,and the soil-structure interaction model is applied to analyze the responses of the structure,which is the same as the model used in GRDM2.The time-history analysis method(THAM)is used to evaluate the accuracy of the proposed simplified methods.Results show that the error of GRDM1 is about 20%,while the error is only 5%for GRDM2 and GRDM3.Among the three proposed methods,GRDM3 has obvious advantages regarding calculation efficiency and accuracy.Therefore,it is recommended to use GRDM3 for the seismic response analysis of underground structures that have conventional simple or complex cross sections. 展开更多
关键词 underground structures seismic analysis response displacement method equivalent seismic load complex cross section
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Design & Test of an Advanced Web Security Analysis Tool (AWSAT)
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作者 Meenakshi S. P. Manikandaswamy Vijay Madisetti 《Journal of Software Engineering and Applications》 2024年第5期448-461,共14页
Considering the escalating frequency and sophistication of cyber threats targeting web applications, this paper proposes the development of an automated web security analysis tool to address the accessibility gap for ... Considering the escalating frequency and sophistication of cyber threats targeting web applications, this paper proposes the development of an automated web security analysis tool to address the accessibility gap for non-security professionals. This paper presents the design and implementation of an automated web security analysis tool, AWSAT, aimed at enabling individuals with limited security expertise to effectively assess and mitigate vulnerabilities in web applications. Leveraging advanced scanning techniques, the tool identifies common threats such as Cross-Site Scripting (XSS), SQL Injection, and Cross-Site Request Forgery (CSRF), providing detailed reports with actionable insights. By integrating sample payloads and reference study links, the tool facilitates informed decision-making in enhancing the security posture of web applications. Through its user-friendly interface and robust functionality, the tool aims to democratize web security practices, empowering a wider audience to proactively safeguard against cyber threats. 展开更多
关键词 Web Security Automated analysis Vulnerability Assessment Web Scanning cross-Site Scripting SQL Injection cross-Site Request Forgery
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Validation and application of three-dimensional discontinuous deformation analysis with tetrahedron finite element meshed block 被引量:4
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作者 Jun Liu Zheng Nan Ping Yi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第6期1602-1616,共15页
In the last decade, three dimensional discontin- uous deformation analyses (3D DDA) has attracted more and more attention of researchers and geotechnical engineers worldwide. The original DDA formulation utilizes a ... In the last decade, three dimensional discontin- uous deformation analyses (3D DDA) has attracted more and more attention of researchers and geotechnical engineers worldwide. The original DDA formulation utilizes a linear displacement function to describe the block movement and deformation, which would cause block expansion under rigid body rotation and thus limit its capability to model block de- formation. In this paper, 3D DDA is coupled with tetrahe- dron finite elements to tackle these two problems. Tetrahe- dron is the simplest in the 3D domain and makes it easy to implement automatic discretization, even for complex topol- ogy shape. Furthermore, element faces will remain planar and element edges will remain straight after deformation for tetrahedron finite elements and polyhedral contact detection schemes can be used directly. The matrices of equilibrium equations for this coupled method are given in detail and an effective contact searching algorithm is suggested. Valida- tion is conducted by comparing the results of the proposed coupled method with that of physical model tests using one of the most common failure modes, i.e., wedge failure. Most of the failure modes predicted by the coupled method agree with the physical model results except for 4 cases out of the total 65 cases. Finally, a complex rockslide example demon- strates the robustness and versatility of the coupled method. 展开更多
关键词 three-dimensional discontinuous deformation analysis Finite element method Coupled method Valida-tion
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THREE-DIMENSIONAL ANALYSIS OF FUNCTIONALLY GRADED PLATE BASED ON THE HAAR WAVELET METHOD 被引量:2
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作者 Zhang Chun Zhong Zheng 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第2期95-102,共8页
A three-dimensional analysis of a simply-supported functionally graded rectangular plate with an arbitrary distribution of material properties is made using a simple and effective method based on the Haar wavelet. Wit... A three-dimensional analysis of a simply-supported functionally graded rectangular plate with an arbitrary distribution of material properties is made using a simple and effective method based on the Haar wavelet. With good features in treating singularities, Haar series solution converges rapidly for arbitrary distributions, especially for the case where the material properties change rapidly in some regions. Through numerical examples the influences of the ratio of material constants on the top and bottom surfaces and different material gradient distributions on the structural response of the plate to mechanical stimuli are studied. 展开更多
关键词 functionally graded material rectangular plate Haar wavelet three-dimensional analysis
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Reconstruction of heat flux profile on the HL-2A divertor plate with a three-dimensional analysis model 被引量:1
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作者 高金明 李伟 +4 位作者 夏志伟 潘宇东 卢杰 易萍 刘仪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期389-393,共5页
A three-dimensional analysis model based on the finite element method (FEM) is developed, which can derive the evolution and distribution characteristics of heat flux deposited on the divertor plate from the surface... A three-dimensional analysis model based on the finite element method (FEM) is developed, which can derive the evolution and distribution characteristics of heat flux deposited on the divertor plate from the surface temperature measured by infrared thermography diagnostics. The numerical simulations of surface heating due to localized power bursts and the power deposition calculations demonstrate that this analysis can provide accurate results and useful information about localized hot spots compared with the normal one- and two-dimensional calculations. In this paper, the details of this three- dimensional analysis are presented, and some results in ohmic heating and electron cyclotron resonant heating (ECRH) discharge on HL-2A are given. 展开更多
关键词 three-dimensional analysis heat flux divertor plate
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Three-dimensional admittance analysis of lithospheric elastic thickness over the Louisville Ridge 被引量:1
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作者 Minzhang Hu Hui Li +2 位作者 Chongyang Shen Lelin Xing Hongtao Hao 《Earthquake Science》 CSCD 2016年第2期117-125,共9页
Using bathymetry and altimetric gravity anomalies, a 1°×9 1° lithospheric effective elastic thickness(Te) model over the Louisville Ridge and its adjacent regions is calculated using the moving window... Using bathymetry and altimetric gravity anomalies, a 1°×9 1° lithospheric effective elastic thickness(Te) model over the Louisville Ridge and its adjacent regions is calculated using the moving window admittance technique. For comparison, three bathymetry models are used: general bathymetric charts of the oceans, SIO V15.1,and BAT_VGG. The results show that BAT_VGG is more suitable for calculating T e than the other two models. T e along the Louisville Ridge was re-evaluated. The southeast of the ridge has a medium Te of 10–20 km, while Te increases dramatically seaward of the Tonga-Kermadec trench as a result of the collision of the Pacific and IndoAustralian plates. 展开更多
关键词 three-dimensional admittance analysis Lithospheric effective elastic thickness BATHYMETRY Gravity Louisville Ridge
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AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES;PART I—TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES 被引量:2
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作者 康顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第5期489-495,共7页
Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rul... Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rules are (1) for a rotor cascade without shroud band, the total number of nodal points equals that the saddle points on the skin-friction line vector fields in eachpitch range; (2) for an annular or straight cascade with no-clearances at blade ends, the total number of saddle points is two more than that of nodal points on the skin-friction line fields in a pitch; (3) the total number of saddles in the secondary flow fields on cross-sections in cascade is one less than that of nodes; (4) in the section streamline vector fields on a meridian surface penetrating a flow passage, and on leading and trailing edge sections, the total number of nodes is equal to that of saddles; (5) on the streamline vector fields of a blade-to-blade surface, the total number of nodes is one less than that of saddles. 展开更多
关键词 node TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES AN APPLICATION OF TOPOLOGICAL analysis TO STUDYING THE three-dimensional FLOW IN CASCADES PART I
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Undrained Stability Analysis of Three-Dimensional Rectangular Trapdoor in Clay 被引量:1
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作者 尹小军 谢骏 《Journal of Donghua University(English Edition)》 EI CAS 2020年第4期334-339,共6页
A new collapse model of the trapdoors,three-dimensional rectangular trapdoor(3DRT),is presented for ground surface collapse.Undrained stability of 3DRT is examined with the upper bound method of plasticity limit analy... A new collapse model of the trapdoors,three-dimensional rectangular trapdoor(3DRT),is presented for ground surface collapse.Undrained stability of 3DRT is examined with the upper bound method of plasticity limit analysis theory.The soil where the trapdoors are located is assumed to be a perfectly plastic model with a Tresca yield criterion.Block analysis technique is employed to investigate the collapse of 3DRT.The model is divided into five different block types and added up to ten rigid blocks.According to the law of conservation of energy,the critical stability ratios of 3DRT are obtained through a search proceeding.The results of upper bound solution for 3DRT are given,and three trapdoor models with depth various are discussed during the application in the stability analysis of square trapdoors.The critical stability ratios can be used in the design of underground excavation and support force. 展开更多
关键词 three-dimensional rectangular trapdoor upper bound solution stability ratio rigid block block analysis technique
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Three-dimensional mapping and comparative analysis of the distal human corpus cavernosum and the inflatable penile prosthesis
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作者 Tariq S Hakky Daniel Ferguson +3 位作者 Philippe E Spiess Paul Bradley Tom FLue Rafael E Carrion 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第4期567-570,I0012,共5页
The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts an... The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm (36.01-37.0 mm), which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip. 展开更多
关键词 corpus cavernosum penile prosthesis three-dimensional analysis
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MODELING OF LIGHT SPECULAR REFLECTION FROM PLAIN-KNITTED FABRICS: A THREE-DIMENSIONAL ANALYSIS
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作者 陶肖明 《Journal of China Textile University(English Edition)》 EI CAS 1997年第3期1-7,共7页
The paper applies a mathematical model[1] for specular reflection to plain-knitted fabrics by using a three-dimensional analysis. Computer simulation of goniophotometric curves is generated based oa the model. Correct... The paper applies a mathematical model[1] for specular reflection to plain-knitted fabrics by using a three-dimensional analysis. Computer simulation of goniophotometric curves is generated based oa the model. Correction factors are introduced by taking into consideration of geometry of the instrument used. Comparison between the simulated and the measured curves of a straight monofilament yarn with various orientation angles is carried out and reasonable agreement has been obtained. 展开更多
关键词 specular REFLECTION plain-knitted FABRICS three-dimensional analysis computer simulation goniophotometric CURVES
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Demonstration of the refined three-dimensional structure of mesoscale eddies and computational error estimates via Lagrangian analysis
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作者 Heqing Yin Haijin Dai +2 位作者 Weimin Zhang Xueyan Zhang Pinqiang Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第7期146-164,共19页
In previous studies,Lagrangian analyses were used to assess large-scale ocean circulation,and the Lagrangian coherent structure could also reveal the evolution of the two-dimensional structure of the mesoscale eddies.... In previous studies,Lagrangian analyses were used to assess large-scale ocean circulation,and the Lagrangian coherent structure could also reveal the evolution of the two-dimensional structure of the mesoscale eddies.However,few studies have demonstrated the three-dimensional structure of the mesoscale eddies via Lagrangian analysis.Compared with previous studies,which investigated the eddy structure via a Eulerian view,we used a Lagrangian view to provide a different perspective to study the eddy structure.An idealized cyclonic mesoscale eddy is built up over a seamount,and it presents downwelling inside the eddy and upwelling alongside the eddy formed within a closed circulation system.This structure is difficult to display via a Eulerian analysis.However,the trajectories of particles can well demonstrate the full cycle:the fluid sank and rotated inside the eddies,converged to the upwelling zone of the bottom layer and returned to the surface through upwelling.We also applied a Lagrangian analysis to a realistic simulation.As a significant phenomenon in the South China Sea,the dipole structure of the anticyclonic eddy(AE)/cyclonic eddy(CE)pair off of central Vietnam has been well studied but mainly at the sea surface.With a Lagrangian analysis,we illustrate the three-dimensional structure of the eddy pair:the fluid sank(rose)and rotated inside the AE(CE).More importantly,the trajectories of the particles suggested that there was no fluid exchange between the two eddies since the strong boundary jet separates them from each other.All the conclusions above have been verified and are supported by the computational error estimate.With a selected time step and integral period,the computational errors always present small values,although they increase with strong divergent and vertical diffusive flow. 展开更多
关键词 mesoscale eddy Lagrangian analysis three-dimensional structure
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AN APPLICATION OF TOPOLOGICAL METHOD TO ANALYSING THE THREE-DIMENSIONAL FLOW IN CASCADES(Ⅱ)-TOPOLOGICAL ANALYSIS ON THE VECTOR FIELD PATTERNS OF SKINFRICTIONS AND SECTION STREAMLINES
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作者 康顺 王仲奇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第12期1119-1127,共9页
With an application of topological analysis, in this paper the skin-friction line patterns on compressor and turbine cascade surfaces are depicted and the streamline patterns of the secondary flow fields in the cross-... With an application of topological analysis, in this paper the skin-friction line patterns on compressor and turbine cascade surfaces are depicted and the streamline patterns of the secondary flow fields in the cross-section of a curved pipe and a turbine cascade are drawn under given conditions. In addition the structures of vortices within three-dimensional viscous flow fields in cascades are analysed. 展开更多
关键词 topological analysis separation flow three-dimensional flow visualization turbine COMPRESSOR VORTEX
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A three-dimensional ocean general circulation model for mesoscale eddies——Ⅱ Diagnostic analysis
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作者 Moto Ikeda 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第1期29-43,共15页
A three-dimensional density field associated with mesoscaie unstable waves generated by the 3-D, primitive-equation model (Wang and Ikeda, 1996) is provided to the quasi-geostrophic pressure tendency and ω-equations,... A three-dimensional density field associated with mesoscaie unstable waves generated by the 3-D, primitive-equation model (Wang and Ikeda, 1996) is provided to the quasi-geostrophic pressure tendency and ω-equations, and to the (ageostrophic) Q-vector equation. Diagnostic analyses, analogous to the approaches in meteorology: ω-equation and Q-vector method, are for the first time developed to examine the mesoscaie dynamical processes and mechanisms of the unstable waves propagating in the mid-latitude ocean. The weaknesses and strengths of these two diagnostic approaches are evaluated and compared to the model results. The Q-vector method is then recommended to diagnose the vertical motion associated with the mesoscaie dynamics from a hydrographic CTD (conductivity-temperature-depth) array, while the quasi-geostrophic equations produce some small-scale features (errors) in the diagnosed fields. 展开更多
关键词 Diagnostic analysis A three-dimensional ocean general circulation model for mesoscale eddies
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Structure and Bonding in Some Gd(Ⅲ) Metal Complexes Studied by Three-Dimensional X-Ray Analysis and ^(155)Gd Mssbauer Spectroscopy
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作者 王军虎 Takahashi Masashi +1 位作者 Kitazawa Takafumi Takeda Masuo 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第6期647-653,共7页
Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the... Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the structure and bonding in lanthanide and actinide metal complexes using 166Er, t55Gd, and 237Np Mtissbauer spectroscopies in connection with single-crystal and/or powder X-ray diffraction, making clear the differences on their structures as well as the differences in the participation of 4f and 5f orbitals in the chemical bonds. In this article, the crystal structures of two novel Gd(Ⅲ) acetylacetonato complexes, Gd(pta)3 · 2H2O (pta = 1,1,1 -trifluoro-5,5-dimethy 1-2,4-hexanedione) and Gd(bfa)3 · 2H2O (bfa = 1, 1, 1 -trifluoro-4-phenyl-2-4-butanedione) were reported. Though both of them were dihydrate and had distorted square antiprismatical structure, Gd(pta)3 · 2H2O crystallizes in the P 2 1/n (#14) monoclinic space group and its lattice parameters are a = 1.4141(6) nm, b = 1.0708(3) nm, c =2.2344(4) nm, β =952.4(2)°, and Gd(bfa)3· 2H2O crystallizes in P 212121 orthorhombic space group and its lattice parameters were a = 1.322 (1) nm, b = 2.295 (1) nm, c = 1. 0786(8) nm. In the meantime, the authors had finished a systematic investigation on the ^155Gd Mossbauer isomer shift (δ) of various Gd(Ⅲ) metal complexes having a different coordination number (C.N.) and different ratios coordinating oxygen to nitrogen. A tendency for the 6 value to decrease with an increase in the C.N, and the number of the nitrogen atom coordinating to Gd was confirmed. This indicated that the Gd-O and/or Gd-N bond in the investigated Gd(Ⅲ) metal complexes had a small covalent contribution, which was possible to be deduced from the O and/or N atoms of the lisands donating electrons to 6s, 5d, and 4f orbitals of Gd. 展开更多
关键词 Gd(Ⅲ) metal complex crystal structure bonding ^155Gd Mossbauer spectroscopy three-dimensional X-ray analysis covalent contribution rare earths
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Analysis of Cr Atoms Three-Dimensional Deposition Characteristics
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作者 Hua-Lei Yang Wen-Tao Zhang Jian Yang 《World Journal of Nano Science and Engineering》 2011年第3期73-78,共6页
The semi-classical model is used to simulate the three-dimensional trajectory and deposition distribution of the chromium atoms in the Gaussian laser standing wave field using the Runge-Kutta method, and then the thre... The semi-classical model is used to simulate the three-dimensional trajectory and deposition distribution of the chromium atoms in the Gaussian laser standing wave field using the Runge-Kutta method, and then the three-dimensional deposition stripes are also given, besides, the effects of atomic beam divergence, chromatic aberration and spherical aberration on deposition structure are also analyzed. 展开更多
关键词 three-dimensional analysis ATOM Deposition CR ATOMS Gaussian Laser STANDING Wave Field
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