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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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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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Processing map and dynamic recrystallization behaviours of 316LN-Mn austenitic stainless steel
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作者 Shaolong Sheng Yanxin Qiao +2 位作者 Ruzong Zhai Mingyue Sun Bin Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第12期2386-2396,共11页
The hot deformation behaviours of 316LN-Mn austenitic stainless steel were investigated by uniaxial isothermal compression tests at different temperatures and strain rates.The microstructural evolutions were also stud... The hot deformation behaviours of 316LN-Mn austenitic stainless steel were investigated by uniaxial isothermal compression tests at different temperatures and strain rates.The microstructural evolutions were also studied using electron backscatter diffraction.The flow stress decreases with the increasing temperature and decreasing strain rate.A constitutive equation was established to characterize the relationship among the deformation parameters,and the deformation activation energy was calculated to be 497.92 k J/mol.Processing maps were constructed to describe the appropriate processing window,and the optimum processing parameters were determined at a temperature of 1107-1160℃ and a strain rate of 0.005-0.026 s^(-1).Experimental results showed that the main nucleation mechanism is discontinuous dynamic recrystallization(DDRX),followed by continuous dynamic recrystallization(CDRX).In addition,the formation of twin boundaries facilitated the nucleation of dynamic recrystallization. 展开更多
关键词 austenitic stainless steel processing map dynamic recrystallization constitutive equation
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Spatial and temporal variation process of seabed dynamic response induced by the internal solitary wave
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作者 Zhuangcai Tian Lei Jia +3 位作者 Naili Hu Susheng Wang Mingwei Zhang Guoqing Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期142-149,共8页
Internal solitary wave(ISW)is often accompanied by huge energy transport,which will change the pore water pressure in the seabed.Based on the two-dimensional Biot consolidation theory,the excess pore water pressure in... Internal solitary wave(ISW)is often accompanied by huge energy transport,which will change the pore water pressure in the seabed.Based on the two-dimensional Biot consolidation theory,the excess pore water pressure in seabed was simulated,and the spatiotemporal distribution characteristics of excess pore water pressure was studied.As the parameters of both ISW and seabed can affect the excess pore water pressure,the distribution of pore water pressure showed both dissipation and phase lag.And parametric studies were done on these two phenomena.Due to influenced by the phase lag of excess pore water pressure,the penetration depth under the site of northern South China Sea with total water depth 327 m,induced by typical internal solitary wave increased by 26.19%,53.27%and 149.86%from T_(0)to T_(0.5)in sand silt,clayey silt and fine sand seabed,respectively.That means the effect of ISW on seabed will be underestimated if we only take into accout the penetration depth under ISW trough,especially for fine sand seabed.In addition,the concept of“amplitude-depth ratio”had been introduced to describe the influence of ISW on seabed dynamic response in the actual marine environment.In present study,it is negatively correlated with the excess pore water pressure,and an ISW with smaller amplitude-depth ratio can wide the range of lateral impacts.Our study results help understand the seabed damage induced by the interaction between ISW and seabed. 展开更多
关键词 internal solitary wave pore water pressure SEABED dynamic response variation process
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Dynamic evaluation of a scaled-down heat pipe-cooled system during start-up/shut-down processes using a hardware-in-the-loop test approach
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作者 Jiao‑Long Deng Tian‑Shi Wang +3 位作者 En‑Ping Zhu Shuo Yuan Xiao‑Jing Liu Xiang Chai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期174-198,共25页
Micro-mobile heat pipe-cooled nuclear power plants are promising candidates for distributed energy resource power genera-tors and can be flexibly deployed in remote places to meet increasing electric power demands.How... Micro-mobile heat pipe-cooled nuclear power plants are promising candidates for distributed energy resource power genera-tors and can be flexibly deployed in remote places to meet increasing electric power demands.However,previous steady-state simulations and experiments have deviated significantly from actual micronuclear system operations.Hence,a transient analysis is required for performance optimization and safety assessment.In this study,a hardware-in-the-loop(HIL)approach was used to investigate the dynamic behavior of scaled-down heat pipe-cooled systems.The real-time features of the HIL architecture were interpreted and validated,and an optimal time step of 500 ms was selected for the thermal transient.The power transient was modeled using point kinetic equations,and a scaled-down thermal prototype was set up to avoid mod-eling unpredictable heat transfer behaviors and feeding temperature samples into the main program running on a desktop PC.A series of dynamic test results showed significant power and temperature oscillations during the transient process,owing to the inconsistency of the rapid nuclear reaction rate and large thermal inertia.The proposed HIL approach is stable and effective for further studying of the dynamic characteristics and control optimization of solid-state small nuclear-powered systems at an early prototyping stage. 展开更多
关键词 Micro-heat pipe-cooled nuclear reactor HARDWARE-IN-THE-LOOP dynamic evaluation Start-up/shut-down processes
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Educational Process as Something Dynamic
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作者 Jose Manuel Salum Tome 《Journal of Philosophy Study》 2023年第5期220-228,共9页
If we conceive the educational process as something dynamic,which basically combines what is given with what is emerging,we will understand that there are protagonists in it who have a fundamental role in this process... If we conceive the educational process as something dynamic,which basically combines what is given with what is emerging,we will understand that there are protagonists in it who have a fundamental role in this process,or perhaps we should say that,in this process,each and every one of the agents has a leading role.So,talking about curriculum implies that the subject can be approached from different perspectives,some more legitimate than others,some broader than others and,what is even more notorious,some more dynamic than others.It is in these differences where the essence of the educational process is conjugated,namely,in the conception of the curriculum,so it is worth asking:What are the educational units understanding by“development of their own curricular projects”?What are they actually doing?What curricular decisions do they make?Not only these questions arise,but many more,not to mention that it is also legitimate to doubt the capacity and preparation of teachers and educational units to undertake a process of conscious and responsible construction of an effective curriculum.It is interesting to approach the subject critically,not to reconsider the theoretical aspects,in which we find a wide range of postulates,but rather to revitalize the pedagogical practice in the place where it actually occurs,the classroom,and from there to enable discussion,and analysis of the problem,assuming that a paradigm change is urgent at all levels,otherwise,the entire society will suffer even more marked dehumanization.There are many challenges and requirements that fall on the educational task,and there are many who express their opinion,judge,and dare to formulate lapidary sentences on the subject of education,with no more foundation than that allowed by a fragmented look at reality.Therefore,a deeper look can shed light on why it has not yet been possible to reach a more optimal level in the quality indices,nor has equity been achieved,and what is worse,it seems that all that has been said is slipping away through the window of the classrooms to end up in the realm of abstraction,from which it will not be possible to bring what is real and everyday.Thus,this work will also be a proposal for educational agents,a proposal that should not be kept together with others,but rather,hand in hand with the contingent,could give way to a better understanding of the problem. 展开更多
关键词 educational process dynamIC CURRICULUM
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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 流动力学 泥石流 大地震 滑坡 河口 进程 汶川 引发
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Process design and intensification of multicomponent azeotropes special distillation separation via molecular simulation and system optimization
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作者 Chunliang Liu Jianhui Zhong +5 位作者 Ranran Wei Jiuxu Ruan Kaicong Wang Zhaoyou Zhu Yinglong Wang Limei Zhong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期24-44,共21页
This work provides an overview of distillation processes,including process design for different distillation processes,selection of entrainers for special distillation processes,system integration and intensification ... This work provides an overview of distillation processes,including process design for different distillation processes,selection of entrainers for special distillation processes,system integration and intensification of distillation processes,optimization of process parameters for distillation processes and recent research progress in dynamic control strategies.Firstly,the feasibility of using thermodynamic topological theories such as residual curve,phase equilibrium line and distillation boundary line to analyze different separation regions is discussed,and the rationality of distillation process design is discussed by using its feasibility.Secondly,the application of molecular simulation methods such as molecular dynamics simulation and quantum chemical calculation in the screening of entrainer is discussed for the extractive distillation process.The thermal coupling mechanism of different distillation processes is used to explore the process of different process intensifications.Next,a mixed integer nonlinear optimization strategy for the distillation process based on different algorithms is introduced.Finally,the improvement of dynamic control strategies for different distillation processes in recent years is summarized.This work focuses on the application of process intensification and system optimization in the design of distillation process,and analyzes the challenges,prospects,and development trends of distillation technology in the separation of multicomponent azeotropes. 展开更多
关键词 Azeotrope separation process design Optimization algorithm process integration dynamic control Entrainer selection
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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 李平 张捷 +1 位作者 许小可 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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Adaptive Method’s Application for the Identification Systems in Dynamic Weighing
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作者 Pavel Shakun 《Journal of Traffic and Transportation Engineering》 2024年第4期175-186,共12页
In this work,the possibility of adaptive algorithm in WIM(weight-in-motion)systems,in which fibre optic sensors are used,is shown.Appointment of dynamic weighing device consists in determining the weight and type of v... In this work,the possibility of adaptive algorithm in WIM(weight-in-motion)systems,in which fibre optic sensors are used,is shown.Appointment of dynamic weighing device consists in determining the weight and type of vehicle.In this work an algorithm for processing the input data and fiber optic sensor to create the database used in the algorithm is presented.The results of the algorithm for the identification of vehicles are given.The conclusions are made and options of increasing the accuracy of the identification algorithm are considered. 展开更多
关键词 dynamic weighing adaptive filtering digital data processing
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A dynamical neural network approach for distributionally robust chance-constrained Markov decision process 被引量:1
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作者 Tian Xia Jia Liu Zhiping Chen 《Science China Mathematics》 SCIE CSCD 2024年第6期1395-1418,共24页
In this paper,we study the distributionally robust joint chance-constrained Markov decision process.Utilizing the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms und... In this paper,we study the distributionally robust joint chance-constrained Markov decision process.Utilizing the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms under the moment-based uncertainty set.To cope with the non-convexity and improve the robustness of the solution,we propose a dynamical neural network approach to solve the reformulated optimization problem.Numerical results on a machine replacement problem demonstrate the efficiency of the proposed dynamical neural network approach when compared with the sequential convex approximation approach. 展开更多
关键词 Markov decision process chance constraints distributionally robust optimization moment-based ambiguity set dynamical neural network
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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 王先甲 顾翠伶 +1 位作者 吕少杰 全吉 《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:10
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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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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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