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Study on the coupling calculation method for the launch dynamics of a self-propelled artillery multibody system considering engraving process 被引量:1
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作者 Shujun Zhang Xiaoting Rui +1 位作者 Hailong Yu Xiaoli Dong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期67-85,共19页
The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational eff... The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational efficiency,and imprecise analyses of system dynamic responses found in the dynamics research of intricate multi-rigid-flexible body systems,such as self-propelled artillery.This advancement aims to enhance the firing accuracy and launch safety of self-propelled artillery.Recognizing the shortfall of overlooking the band engraving process in existing theories,this study introduces a novel coupling calculation methodology for the launch dynamics of a self-propelled artillery multibody system.This method leverages the ABAQUS subroutine interface VUAMP to compute the dynamic response of the projectile and barrel during the launch process of large-caliber self-propelled artillery.Additionally,it examines the changes in projectile resistance and band deformation in relation to projectile motion throughout the band engraving process.Comparative analysis of the computational outcomes with experimental data evidences that the proposed method offers a more precise depiction of the launch process of self-propelled artillery,thereby enhancing the accuracy of launch dynamics calculations for self-propelled artillery. 展开更多
关键词 Self-propelled artillery Engraving process Multibody system dynamics Launch dynamics
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Dynamical Solidification Behaviors and Metal Flow during Continuous Semisolid Extrusion Process of AZ31 Alloy 被引量:10
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作者 Renguo Cuan Liqing Chen +1 位作者 Jiangping Li Fuxing Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第3期395-400,共6页
In this paper, a novel near-net-shape forming process, continuous semisolid extrusion process (CSEP) of AZ31 alloy was proposed, and the dynamical solidification behaviors and metal flow during the process were firs... In this paper, a novel near-net-shape forming process, continuous semisolid extrusion process (CSEP) of AZ31 alloy was proposed, and the dynamical solidification behaviors and metal flow during the process were firstly investigated. During casting AZ31 alloy by this process, non-uniform microstructure distributions and non- equilibrium solidification region near the roll surface were found in the roll-shoe gap. Microstructural evolution from dendrite to rosette and spherical grains was observed during the casting by CSEP. Casting temperature, roll-shoe gap width and cooling ability have great effect on casting process and metal flow, so these factors should be carefully controlled, a proper casting temperature of 710-750℃ is suggested. The white α phases were strongly stretched during the processing, and the remnant liquids are correspondingly distributes along the solid phase boundaries and also show stripped lines. 展开更多
关键词 dynamical solidification Continuous semisolid extrusion process Micro structural evolution AZ31 alloy
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Analysis on the Dynamical Process of Donghekou Rockslide-Debris Flow Triggered by 5.12 Wenchuan Earthquake 被引量:8
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作者 SUN Ping ZHANG Yongshuang +1 位作者 SHI Jusong CHEN Liwei 《Journal of Mountain Science》 SCIE CSCD 2011年第2期140-148,共9页
Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts... Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts to the landscape and socioeconomic structure. In order to analyze the dynamical process of this kind of geo-hazard, the Donghekou rockslide-debris flow is given as an example in this paper. This event, which killed 780 people, initiated at an elevation of 1300 m with a total long run-out distance of more than 2400 m. The slide mass is mainly composed of dolomite limestone and siliceous limestone of Sinian system, together with carbon slate and phyllite of Cambrian. During the processes from slide initiation to the final cessation of slide movement, five dynamic stages took place, here identified as the initiation stage, the acceleration of movement stage, the air-blast effect stage, the impact and redirection stage and the long runout slidematerial accumulation stage. Field investigations indicate that due to the effects of the earthquake, the dynamics of the Donghekou rockslide-debris flow are apparently controlled by geologic and tectonic conditions, the local geomorphological aspects of the terrain, and the microstructural and macroscopic mechanical properties of rocks which compose the slide mass. These three main factors which dictate the Donghekou rockslide-debris flow dynamics are discussed in detail in this paper, and significant results of field investigations and tests of materials are presented. The above dynamical processes are analyzed in this paper, and some useful conclusions have been gained. 展开更多
关键词 dynamical process Donghekou Rockslide-debris flow Wenchuan earthquake
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Deep structure of the Southeast Asian curved subduction system and its dynamic process
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作者 Weiwei DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期701-704,共4页
The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.B... The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.Based on the deep seismic tomography using long-period natural earthquake data,in this study,the deep structure and material circulation of the curved subduction system in Southeast Asia was studied,and the dynamic processes since 100 million years ago was reconstructed.It is pointed out that challenges still exist in the precise reconstruction of deep mantle structures of the study area,the influence of multi-stage subduction on deep material exchange and shallow magma activity,as well as the spatiotemporal evolution and coupling mechanism of multi-plate convergence.Future work should focus on high-resolution land-sea joint 3-D seismic tomography imaging of the curved subduction system in the Southeast Asia,combined with geochemical analysis and geodynamic modelling works. 展开更多
关键词 curved subduction system deep structure material recycling dynamic process Southeast Asia
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A process monitoring method for autoregressive-dynamic inner total latent structure projection
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作者 CHEN Yalin KONG Xiangyu LUO Jiayu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1326-1336,共11页
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos... As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system. 展开更多
关键词 dynamic characteristic fault detection feature extraction process monitoring projection to latent structure(PLS) quality-related spatial partitioning
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Numerical simulation for dynamical processes of seaice
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《Acta Oceanologica Sinica》 SCIE CAS CSCD 1997年第3期303-325,共16页
NumericalsimulationfordynamicalprocessesofseaiceWuHuiding,BaiShan,ZhangZhanhaiandLiGuoqing(ReceivedMay16,199... NumericalsimulationfordynamicalprocessesofseaiceWuHuiding,BaiShan,ZhangZhanhaiandLiGuoqing(ReceivedMay16,1996;acceptedJanuary... 展开更多
关键词 seaice SIMULATION processES NUMERICAL dynamical
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Dynamical Influence of Nodes Revisited: A Markov Chain Analysis of Epidemic Process on Networks
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作者 LI Ping ZHANG Jie +1 位作者 XU Xiao-Ke SMALL Michael 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第4期248-251,共4页
We provide a theoretical analysis of node importance from the perspective of dynamical processes on networks.In particular,using Markov chain analysis of the susceptible-infected-susceptible (SIS) epidemic model on ne... We provide a theoretical analysis of node importance from the perspective of dynamical processes on networks.In particular,using Markov chain analysis of the susceptible-infected-susceptible (SIS) epidemic model on networks,we derive the node importance in terms of dynamical behaviors on network in a theoretical way.It is found that this quantity happens to be the eigenvector centrality under some conditions,which bridges the topological centrality measure of the nodes with the dynamical influence of the nodes for the dynamical process.We furthermore discuss the condition under which the eigenvector centrality is valid for dynamical phenomena on networks. 展开更多
关键词 process dynamical EIGENVECTOR
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A Low-Area, Low-Power Dynamically Reconfigurable 64-Bit Media Signal Processing Adder
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作者 Priscilla Sharon Allwin Chien-In Henry Chen 《Journal of Computer and Communications》 2021年第3期54-69,共16页
Multimedia devices like cellphones, radios, televisions, and computers require low-area and energy-efficient dynamically reconfigurable data paths to process the greedy computation algorithms for real-time audio/video... Multimedia devices like cellphones, radios, televisions, and computers require low-area and energy-efficient dynamically reconfigurable data paths to process the greedy computation algorithms for real-time audio/video signal<span> and image processing. In this paper, a novel low-area, energy-efficient 64-bit dynamically reconfigurable adder is presented. This adder can be run-time configured to different reconfigurable word lengths based on the partition signal commands provided. Moreover, the design is partitioned into sub-blocks based on functionality to save power, </span><i><span>i.e.</span></i><span>, configuring the computation only for the necessary data path, thus avoiding the unnecessary switching power from the data path computed values that do not get used. Only functions that are needed are powered on, and the rest of the functionality is powered off. The proposed 64-bit dynamically reconfigurable media signal processing (MSP) adder is implemented in the 180 nm CMOS technology at 1.8 V, requiring an area of 39,478 μm</span><sup><span style="vertical-align:super;">2</span></sup><span> and a power of 79.24 mW. The dynamic MSP adder achieves a 15.7% reduction in area and a 59.2% reduction in power than the 64-bit MSP adder.</span> 展开更多
关键词 Media Signal processing (MSP) Reconfigurable Adder dynamic Reconfiguration
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The tropical Pacific cold tongue mode and its associated main ocean dynamical process in CMIP5 models
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作者 Yang Li QuanLiang Chen +5 位作者 JianPing Li WenJun Zhang MinHong Song Wei Hua HongKe Cai XiaoFei Wu 《Earth and Planetary Physics》 CSCD 2019年第5期400-413,共14页
The cold tongue mode(CTM),which represents the out-of-phase relationship in sea surface temperature anomaly(SSTA)variability between the Pacific cold tongue region and elsewhere in the tropical Pacific,shows a long-te... The cold tongue mode(CTM),which represents the out-of-phase relationship in sea surface temperature anomaly(SSTA)variability between the Pacific cold tongue region and elsewhere in the tropical Pacific,shows a long-term cooling trend in the eastern equatorial Pacific.In this study,we investigate how well the CTM is reproduced in historical simulations generated by the 20 models considered in Phase 5 of the Coupled Model Intercomparison Project(CMIP5).Qualitatively,all 20 models roughly capture the cooling SSTA associated with the CTM.However,a quantitative assessment(i.e.,Taylor diagrams and the ratio of the trend between the simulations and observations)shows that only five of these 20 models(i.e.,CESM1-CAM5,CMCC-CM,FGOALS-g2,IPSL-CM5B-LR,and NorESM1-M)can reproduce with useful accuracy the spatial pattern and long-term trend of the CTM.We find that these five models generally simulate the main ocean dynamical process associated with the CTM.That is,these models adequately capture the long-term cooling trend in the vertical advection of the anomalous temperature by the mean upwelling.We conclude that the performance of these CMIP5 models,with respect to simulations of the long-term cooling trend associated with the vertical advection,and the related long-term decreasing trend of the vertical gradient of the oceanic temperature anomaly,can play an important role in successful reproduction of the CTM. 展开更多
关键词 tropical Pacific La Nina-like cold tongue mode ocean dynamical process CMIP5
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Dynamic recrystallization of Ti-6Al-2Zr-1Mo-1V in β forging process 被引量:2
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作者 欧阳德来 王克鲁 崔霞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期761-767,共7页
The dynamic recrystallization(DRX) behavior of Ti-6Al-2Zr-1Mo-1V alloy was investigated at deformation temperature of 1000-1100 °C and strain rate of 10-3-1.0 s-1 by using compression test.The results show that... The dynamic recrystallization(DRX) behavior of Ti-6Al-2Zr-1Mo-1V alloy was investigated at deformation temperature of 1000-1100 °C and strain rate of 10-3-1.0 s-1 by using compression test.The results show that discontinuous dynamic recrystallization(DDRX) is the predominant recrystallization mechanism at temperature higher than 1050 °C and strain rate lower than 0.01 s-1.Meanwhile,continuous dynamic recrystallization is the main mechanism observed at temperature below 1050 °C and strain rate above 0.01 s-1,mixed with a few DDRX grains.In addition,decreasing strain rate and increasing deformation temperature are found to facilitate the progress of DRX and refinement of grains in the Ti alloy in β forging process. 展开更多
关键词 dynamic recrystallization Ti-6Al-2Zr-1Mo-1V alloy -forging process compression test
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Molecular Dynamic Simulation on the Absorbing Process of Isolating and Coating of α-olefin Drag Reducing Polymer 被引量:1
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作者 李冰 盛翔 +6 位作者 邢文国 董桂霖 刘永军 张长桥 陈祥俊 周宁宁 秦占波 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第6期630-636,745,共8页
The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles wit... The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles with polyurethane as coating material. The distributions of sodium laurate, sodium dodeeyl sulfate, and sodium dodeeyl benzene sulfonate on the surface of α-olefin drag reducing polymer particles were almost the same, but the bending degrees of them were obviously different. The bending degree of SLA molecules was greater than those of the other two surfactant molecules. Simulation results of absorbing and accumulating structure showed that, though hydrophobie properties of surfactant molecules were almost the same, water density around long chain sulfonate sodium was bigger than that around alkyl sulfate sodium. This property goes against useful absorbing and accumulating on the surface of α-olefin drag reducing polymer particles; simulation results of interactions of different surfactant and multiple hydroxyl compounds on surface of particles showed that, interactions of different surfaetant and one kind of multiple hydroxyl compound were similar to those of one kind of surfaetant and different multiple hydroxyl compounds. These two contrast types of interactions also exhibited the differences of absorbing distribution and closing degrees to surface of particles. The sequence of closing degrees was derived from simulation; control step of addition polymerization interaction in coating process was absorbing mass transfer process, so the more closed to surface of particle the multiple hydroxyl compounds were, the easier interactions With isoeyanate were. Simulation results represented the compatibility relationship between surfactant and multiple hydroxyl compounds. The isolating and coating processes of α-olefin drag reducing polymer were further understood on molecule and atom level through above simulation research, and based on the simulation, a referenced theoretical basis was provided for practical optimal selection and experimental preparation of α-olefin drag reducing polymer particles suspension isolation agent. 展开更多
关键词 Molecular dynamic simulation Coating process Multiple hydroxyl compound Addition polymerization Optimal selection Isolation agent
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Study on transient aerodynamic characteristics of parachute opening process 被引量:20
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作者 Li Yu Xiao Ming 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期627-633,共7页
In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficu... In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equations were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo- rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were carried out for canopy geometry, time-dependent pressure difference between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experiments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical predictions were found in good agreement with the experimental results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of significance to the understanding of the mechanics of parachute inflation process. 展开更多
关键词 PARACHUTE Opening process Numerical simulation Flow field characteristics AEROdynamICS Structural dynamics
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Evolutionary game dynamics of combining the Moran and imitation processes 被引量:7
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作者 Xian-Jia Wang Cui-Ling Gu +1 位作者 Shao-Jie Lv Ji Quan 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第2期94-105,共12页
One of the assumptions of previous research in evolutionary game dynamics is that individuals use only one rule to update their strategy. In reality, an individual's strategy update rules may change with the envir... One of the assumptions of previous research in evolutionary game dynamics is that individuals use only one rule to update their strategy. In reality, an individual's strategy update rules may change with the environment, and it is possible for an individual to use two or more rules to update their strategy. We consider the case where an individual updates strategies based on the Moran and imitation processes, and establish mixed stochastic evolutionary game dynamics by combining both processes. Our aim is to study how individuals change strategies based on two update rules and how this affects evolutionary game dynamics. We obtain an analytic expression and properties of the fixation probability and fixation times(the unconditional fixation time or conditional average fixation time) associated with our proposed process. We find unexpected results. The fixation probability within the proposed model is independent of the probabilities that the individual adopts the imitation rule update strategy. This implies that the fixation probability within the proposed model is equal to that from the Moran and imitation processes. The one-third rule holds in the proposed mixed model. However, under weak selection, the fixation times are different from those of the Moran and imitation processes because it is connected with the probability that individuals adopt an imitation update rule. Numerical examples are presented to illustrate the relationships between fixation times and the probability that an individual adopts the imitation update rule, as well as between fixation times and selection intensity. From the simulated analysis, we find that the fixation time for a mixed process is greater than that of the Moran process, but is less than that of the imitation process. Moreover, the fixation times for a cooperator in the proposed process increase as the probability of adopting an imitation update increases; however, the relationship becomes more complex than a linear relationship. 展开更多
关键词 EVOLUTIONARY GAME dynamics MORAN process IMITATION process FIXATION probability FIXATION time
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A wind tunnel simulation of the dynamic processes involved in sand dune formation on the western coast of Hainan Island 被引量:11
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作者 LI Sen LIU Xianwan +2 位作者 LI Huichuan ZHENG Yinghua WEI Xinghu 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期453-468,共16页
The western coast of Hainan Island exhibits a savanna landscape. Many types of sand dunes, including transverse dune ridges, longitudinal dune ridges, elliptical dunes, coppice dunes, and climbing dunes, are widely di... The western coast of Hainan Island exhibits a savanna landscape. Many types of sand dunes, including transverse dune ridges, longitudinal dune ridges, elliptical dunes, coppice dunes, and climbing dunes, are widely distributed in the coastal zone. In winter, high-frequency and high-energy NE winds (dominant winds) are prevalent, with a resultant drift direction (RDD) of S35.6°W. In spring, low-frequency and low-energy SW secondary winds prevail, with a RDD of N25.1°E. Wind tunnel simulations revealed that the airflow over the dune surface is the main factor controlling the erosion and deposition patterns of dune surfaces and the morphological development of dunes. In the region's bidirectional wind environment, with two seasonally distinct energy levels, the airflow over the surface of elliptical dunes, barchan dunes, and transverse dune ridges will exhibit a transverse pattern, whereas the airflow over longitudinal dunes ridges exhibits a lateral pattern and that over climbing dunes exhibits a climbing-circumfluent pattern. These patterns represent different dynamic processes. The coastal dunes on the western coast of Hainan Island are influenced by factors such as onshore winds, sand sources, coastal slopes, rivers, and forest shelter belts. The source of the sand that supplements these dunes particularly influences the development pattern: when there is more sand, the pattern shows positive equilibrium deposition between dune ridges and dunes; otherwise, it shows negative equilibrium deposition. The presence or absence of forest shelter belts also influences deposition and dune development patterns and transformation of dune forms. Coastal dunes and inland desert dunes experience similar dynamic processes, but the former have more diversified shapes and more complex formation mechanisms. 展开更多
关键词 western coast of Hainan Island coastal dune surface airflow dynamic processes wind tunnel simulation
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OPTIMIZATION OF AUTOBODY PANEL STAMPING PROCESS BASED ON DYNAMIC EXPLICIT FINITE ELEMENT METHOD 被引量:6
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作者 X. G. Bao D. N. He +2 位作者 D. Lu C. X. Li J. L. Cheng and J. Y. Jiang( 1) National Mold and Dies CAD Engineering Research Center, Shanghai 200030, China 2) Shanghai Volkswagen Automotive Company Ltd.(SVW), Shanghai 201805, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期387-393,共7页
Taking CPU time cost and analysis accuracy into account, dynamic explicit finite ele- ment method is adopted to optimize the forming process of autobody panels that often have large sizes and complex geometry. In this... Taking CPU time cost and analysis accuracy into account, dynamic explicit finite ele- ment method is adopted to optimize the forming process of autobody panels that often have large sizes and complex geometry. In this paper, for the sake of illustrating in detail how dynamic explicit finite element method is applied to the numerical simulation of the autobody panel forming process,an example of optimization of stamping process pain meters of an inner door panel is presented. Using dynamic explicit finite element code Ls-DYNA3D, the inner door panel has been optimized by adapting pa- rameters such as the initial blank geometry and position, blank-holder forces and the location of drawbeads, and satisfied results are obtained. 展开更多
关键词 dynamic explicit finite element method autobody panel OPTIMIZATION stamping process
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On the Kinematic Characteristics and Dynamic Process of Boundary faults of the Nansha Ultra-crust Layer-Block 被引量:10
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作者 LIU Hailing SUN Yan +4 位作者 GUO Lingzhi SHU Liangshu YANG Shukang ZHOU Di ZHANG Yixiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期452-463,共12页
Abstract The Nansha ultra-crust layer-block is confined by ultra-crustal boundary faults of distinctive features, bordering the Kangtai-Shuangzi-Xiongnan extensional faulted zone on the north, the Baxian-Baram-Yoca-Cu... Abstract The Nansha ultra-crust layer-block is confined by ultra-crustal boundary faults of distinctive features, bordering the Kangtai-Shuangzi-Xiongnan extensional faulted zone on the north, the Baxian-Baram-Yoca-Cuyo nappe faulted zone on the south, the Wan'an-Natuna strike-slip tensional faulted zone on the west and the Mondoro-Panay strike-slip compressive faulted zone on the east. These faults take the top of the Nansha asthenosphere as their common detachmental surface. The Cenozoic dynamic process of the ultra-crust layer-block can be divided into four stages: K2-E21, during which the northern boundary faults extended, this ultra-crust layer-block was separated from the South China-Indosinian continental margin, the Palaeo-South China Sea subducted southwards and the Sibu accretion wedge was formed; E22-E31, during which the Southwest sub-sea basin extended and orogeny was active due to the collision of the Sibu accretion wedge; E32-N11, during which the central sub-sea basin extended, the Miri accretion wedge was formed and “A-type” subduction of the southern margin of the north Balawan occurred; N12-the present, during which large-scale thrusting and napping of the boundary faults in the south and mountain-building have taken place and the South China Sea stopped its extension. 展开更多
关键词 Nansha ultra-crust layer-block boundary fault layer slip glide dip slip strike slip fault system dynamic process
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Emerging of Stochastic Dynamical Equalities and Steady State Thermodynamics from Darwinian Dynamics 被引量:11
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作者 P.Ao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1073-1090,共18页
The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics... The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach: One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium. 展开更多
关键词 non-equilibrium processes Darwinian dynamics generalized Einstein relation absence of detailed balance stochastic dynamical equalities
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A Polynomial Prediction Filter Method for Estimating Multisensor Dynamically Varying Biases 被引量:3
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作者 GAO Yu ZHANG Jian-qiu HU Bo 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第3期240-246,共7页
The estimation of the sensor measurement biases in a multisensor system is vital for the sensor data fusion. A solution is provided for the estimation of dynamically varying multiple sensor biases without any knowledg... The estimation of the sensor measurement biases in a multisensor system is vital for the sensor data fusion. A solution is provided for the estimation of dynamically varying multiple sensor biases without any knowledge of the dynamic bias model parameters. It is shown that the sensor bias pseudomeasurement can be dynamically obtained via a parity vector. This is accomplished by multiplying the sensor uncalibrated measurement equations by a projection matrix so that the measured variable is eliminated from the equations. Once the state equations of the dynamically varying sensor biases are modeled by a polynomial prediction filter, the dynamically varying multisensor biases can be obtained by Kalman filter. Simulation results validate that the proposed method can estimate the constant biases and dynamic biases of multisensors and outperforms the methods reported in literature. 展开更多
关键词 signal processing dynamic bias estimation simulation MULTISENSOR Kalman filter
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A donepezil/cyclodextrin complexation orodispersible film: Effect of cyclodextrin on taste-masking based on dynamic process and in vivo drug absorption 被引量:3
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作者 Tingting Liu Xiaocao Wan +4 位作者 Zheng Luo Chao Liu Peng Quan Dongmei Cun Liang Fang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第2期183-192,共10页
The aim of this study was to develop a palatable donepezil(DP) orodispersible film(ODF)to facilitate the swallowing process and investigate the effect of cyclodextrin on tastemasking based on dynamic process and in vi... The aim of this study was to develop a palatable donepezil(DP) orodispersible film(ODF)to facilitate the swallowing process and investigate the effect of cyclodextrin on tastemasking based on dynamic process and in vivo drug absorption. Complexation of DP with hydroxypropyl-β-cyclodextrin(HP-β-CD) was applied to mask the bitter taste then the prepared complexes were incorporated into ODF using solvent casting method. The tastemasking efficiency was evaluated by e-tongue; meanwhile the pharmacokinetic behavior of DP/HP-β-CD ODF was investigated by in vivo study. Results showed the optimized film was more palatable than donepezil hydrochloride(DH) film and was bioequivalent with DH. The molecular mechanism was revealed by phase solubility study, Fourier-transform infrared spectrometer(FT-IR), Differential scanning calorimeter(DSC), X-ray diffraction(XRD) and molecular modeling. Taste-masking was attributed to the formation of DP/HP-β-CD which was due to moderate interaction between DP and HP-β-CD. The stability of DP/HP-β-CD was decreased because of the acid environment in stomach, which facilitated the absorption of DP. These results extended our understanding about the application of cyclodextrin complexation and provided guidance for the design of ODF especially for drugs with disgusting taste. 展开更多
关键词 DONEPEZIL Orodispersible FILM TASTE-MASKING dynamIC process E-tongue Absorption
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Dynamic experimental study on rock meso-cracks growth by digital image processing technique 被引量:2
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作者 朱珍德 倪骁慧 +3 位作者 王伟 李双蓓 赵杰 武沂泉 《Journal of Central South University》 SCIE EI CAS 2008年第S2期114-120,共7页
A new meso-mechanical testing scheme based on SEM was developed to carry out the experiment of microfracturing process of rocks. The microfracturing process of the pre-crack marble sample on surrounding rock in the im... A new meso-mechanical testing scheme based on SEM was developed to carry out the experiment of microfracturing process of rocks. The microfracturing process of the pre-crack marble sample on surrounding rock in the immerged Long-big tunnel in Jinping Cascade II Hydropower Station under uniaxial compression was recorded by using the testing scheme. According to the stereology theory, the propagation and coalescent of cracks at meso-scale were quantitatively investigated with digital technology. Therefore, the basic geometric information of rock microcracks such as area, angle, length, width, perimeter, was obtained from binary images after segmentation. The failure mechanism of specimen under uniaxial compression with the quantitative information was studied from macro and microscopic point of view. The results show that the image of microfracturing process of the specimen can be observed and recorded digitally. During the damage of the specimen, the distribution of microcracks in the specimen is still subjected to exponential distribution with some microcracks concentrated in certain regions. Finally, the change law of the fractal dimension of the local element in marble sample under different external load conditions is obtained by means of the statistical calculation of the fractal dimension. 展开更多
关键词 MARBLE ROCK FAILURE process digital image processing growth of meso-crack dynamIC observation experimental study
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