The recovery stress of materials has a great potential application in the field of road crack self-repair,composite material self-repair,and so on.Taking into account the diversity of practical application environment...The recovery stress of materials has a great potential application in the field of road crack self-repair,composite material self-repair,and so on.Taking into account the diversity of practical application environments,the recovery stresses of constrained shape memory alloy(SMA)materials in the initial state of austenite and twinned martensite are given respectively in this paper.As for the experimental research,the austenitic SMA is loaded and constrained.The recovery stresses at different stages are observed by increasing the temperature.In terms of the theoretical research,constitutive models with the initial state of austenite and martensite are established respectively based on the one-dimensional macroscopic phenomenon theoretical model and constraints of SMA.These constitutive models can describe the relationship between recovery stress and volume fraction of martensite under temperature loading with different pre-strains.The theoretical model and experimental data in this paper can provide specific support for the practical engineering application of SMA recovery stress.展开更多
The impact of various initial states on the ultimate mechanical properties of medium Mn steel(MMnS)following the hot stamping process is revealed.MMnS blanks with three typical initial states were prepared separately,...The impact of various initial states on the ultimate mechanical properties of medium Mn steel(MMnS)following the hot stamping process is revealed.MMnS blanks with three typical initial states were prepared separately,including hot-rolled,cold-rolled and cold-rolled and annealed(CRA).Their microstructures were observed and analyzed by scanning electron microscopy and electron backscatter diffraction,and their mechanical properties were measured by tensile tests following hot stamping and baking treatments.The results reveal that the microstructure of martensite and residual austenite characterizes the hot-stamped MMnS across different rolling conditions,with CRA state exhibiting a clearly higher residual austenite content compared to the other two states.Meanwhile,CRA state boasts not only the highest tensile strength but also the greatest elongation post-hot stamping treatment.The superior comprehensive mechanical properties are attributed to its unique biphase structure of Mn-rich austenite and Mn-poor ferrite,which emerges in CRA state following a 12 h intercritical annealing and can be partially preserved during the hot stamping process.This structure is instrumental in achieving a higher level of residual austenite,consequently leading to enhanced elongation.展开更多
The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o predicti...The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o prediction system, roles of the initial ocean surface and subsurface states on predicting the 2002/03 CP El Ni?o event are investigated to determine conditions favorable for predicting El Ni?o growth and are isolated in three sets of hindcast experiments. The hindcast is initialized through assimilation of only the sea surface temperature(SST)observations to optimize the initial surface condition(Assim_SST), only the sea level(SL) data to update the initial subsurface state(Assim_SL), or both the SST and SL data(Assim_SST+SL). Results highlight that the hindcasts with three different initial states all can successfully predict the 2002/03 El Ni?o event one year in advance and that the Assim_SST+SL hindcast performs best. A comparison between the various sets of hindcast results further demonstrates that successful prediction is significantly affected by both of the initial surface and subsurface conditions, but in different developing phases of the 2002/03 El Ni?o event. The accurate initial surface state can easier trigger the prediction of the 2002/03 El Ni?o, whereas a more reasonable initial subsurface state can contribute to improving the prediction in the growth of the warm event.展开更多
The maximal evolution speed of any quantum system can be expressed by the quantum speed limit time.In this paper,we consider a model in which the system has a correlation with the environment.The influence of the init...The maximal evolution speed of any quantum system can be expressed by the quantum speed limit time.In this paper,we consider a model in which the system has a correlation with the environment.The influence of the initial correlation between the system and environment on the quantum speed limit is investigated.It is shown that the appearance of non-Markovianity effects causes the speedup of quantum evolution.Moreover,we demonstrate the dependence of quantum dynamical speedup on the quantum coherence of the correlated initial state.展开更多
We investigate the correlations between two qubits in the Grover search algorithm with arbitrary initial states by numerical simulation.Using a set of suitable bases,we construct the reduced density matrix and give th...We investigate the correlations between two qubits in the Grover search algorithm with arbitrary initial states by numerical simulation.Using a set of suitable bases,we construct the reduced density matrix and give the numerical expression of correlations relating to the iterations.For different initial states,we obtain the concurrence and quantum discord compared with the success probability in the algorithm.The results show that the initial states affect the correlations and the limit point of the correlations in the searching process.However,the initial states do not influence the whole cyclical trend.展开更多
The thermal deformation behaviors of the as-cast and wrought modified IN617 nickel-based heat-resistant alloys at different temperatures(1000–1180℃)and strain rates(0.01–1 s^(−1))were studied.The constitutive equat...The thermal deformation behaviors of the as-cast and wrought modified IN617 nickel-based heat-resistant alloys at different temperatures(1000–1180℃)and strain rates(0.01–1 s^(−1))were studied.The constitutive equation was established to describe the relationship of the flow stress,temperature,and strain rate during thermal deformation.The effect of the thermal deformation conditions on the microstructure evolution of alloys was studied using electron backscatter diffraction.The results revealed that the thermal deformation activation energy of the as-cast alloy was greater than that of the wrought alloy.The dynamic recrystallization(DRX)process is slow at intermediate strain rate(0.1 s^(−1))due to the comprehensive influence of various factors,such as the critical strain of DRX nucleation and stored energy.The DRX volume fraction increases with the improvement of deformation temperature.The varied dynamic softening mechanisms induce the different thermal deformation behaviors of as-cast and wrought alloys.The dynamic recovery,discontinuous dynamic recrystallization(DDRX)and nucleation at slip zone caused by strain incompatibility in grains were observed during thermal deformation of as-cast alloys.In the process of thermal deformation of wrought alloys,DDRX was the primary dynamic crystallization mechanism.The continuous dynamic recrystallization was an auxiliary nucleation mechanism.展开更多
Under amplitude damping channel, the dependence of the entanglement on the initial states and , which reduce to four orthogonal Bell states if we take the parameter of states are investigated. We find that the entangl...Under amplitude damping channel, the dependence of the entanglement on the initial states and , which reduce to four orthogonal Bell states if we take the parameter of states are investigated. We find that the entanglements for different initial states will decay along different curves even with the same acceleration and parame-ter of the states. We note that, in an inertial frame, the sudden death of the entanglement for will occur if , while it will not take place for for any α. We also show that the possible range of the sudden death of the entanglement for is larger than that for . There exist two groups of Bell state here we can’t distinguish only by concurrence.展开更多
A chimera state consisting of both coherent and incoherent groups is a fascinating spatial pattern in non-locally coupled identical oscillators. It is thought that random initial conditions hardly evolve to chimera st...A chimera state consisting of both coherent and incoherent groups is a fascinating spatial pattern in non-locally coupled identical oscillators. It is thought that random initial conditions hardly evolve to chimera states. In this work, we study the dependence of chimera states on initial conditions. We show that random initial conditions may lead to chimera states and the chance of realizing chimera states becomes increasing when the model parameters axe moving away from the boundary of their stable regime.展开更多
Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have en...Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.展开更多
There are rich emergent phase behaviors in non-equilibrium active systems.Flocking and clustering are two representative dynamic phases.The relationship between both the phases is still unclear.Herein,we numerically i...There are rich emergent phase behaviors in non-equilibrium active systems.Flocking and clustering are two representative dynamic phases.The relationship between both the phases is still unclear.Herein,we numerically investigate the evolution of flocking and clustering in a system consisting of self-propelled particles with active reorientation.We consider the interplay between flocking and clustering phases with different initial configurations,and observe a domain in steady state order parameter phase diagrams sensitive to the choice of initial configurations.Specifically,by tuning the initial degree of polar ordering,either a more ordered flocking or a disordered clustering state can be observed in the steady state.These results enlighten us to manipulate emergent behaviors and collective motions of an active system,and are qualitatively different from the emergence of a new bi-stable regime observed in aligned active particles due to an explicit attraction[New J.Phys.14073033(2012)].展开更多
In January 2025,the United States issued executive orders that could potentially curtail lesbian,gay,bisexual,transgender,queer,and other sexual and gender minorities(LGBTQ+)rights and federal aid to developing countr...In January 2025,the United States issued executive orders that could potentially curtail lesbian,gay,bisexual,transgender,queer,and other sexual and gender minorities(LGBTQ+)rights and federal aid to developing countries,such as public health programs under the United States Agency for International Development(USAID)[1,2].In the Philippines,USAID has played an important role in funding and supporting initiatives to address the country’s local HIV epidemic[2,3].展开更多
Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a st...Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a straight line in the bilogarithmic ln(1+ e ) ~ lg p plot. The initial effective stress corresponding to the initial void ratio is determined by extrapolation of the bilogarithmic compression line. This new way of extrapolating oedometer test data to the initial void ratio overcomes the difficulty of measuring the residual effective stress of soils in the remolded state. The initial stable compression line of ocean floor deposits under different deposition environments corresponds to the compression line at the sensitivity equal to one. This initial stable compression line obtained in this study is consistent with the available compression line at the sensitivity equal to one which is proposed based on the experimental data of remolded undrained strength and the theoretical concept of Cam clay critical state line.展开更多
Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,...Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,respectively.In these processes,particles involved in the avalanche grow slowly in the early stage and explosively in the later stage,which is clearly different from the continuous and steady growth trend in the monodisperse system.By examining the avalanche propagation,the number growth of particles involved in the avalanche and the slope of the number growth,the initial state can be divided into three stages:T1(nucleation stage),T2(propagation stage),T3(overall avalanche stage).We focus on the characteristics of the avalanche in the T2 stage,and find that propagation distances increase almost linearly in both axial and radial directions in polydisperse systems.We also consider the distribution characteristics of the average coordination number and average velocity for the moving particles.The results support that the polydisperse particle systems are more stable in the T2 stage.展开更多
Based on initial discontinuity state (IDS) of material, a preliminary analytical model was presented to evaluate the effect of interaction of pitting corrosion and fatigue loading on the residual fatigue life of alumi...Based on initial discontinuity state (IDS) of material, a preliminary analytical model was presented to evaluate the effect of interaction of pitting corrosion and fatigue loading on the residual fatigue life of aluminum alloy LY12CZ. A life prediction was carried out using constant and variable amplitude loading for various pitting corrosion levels, and the prediction agreed reasonably with the available test data. The results suggest that the combination of a pit and IDS can be treated as the initial crack size. Pitting corrosion causes a significant decrease in fatigue lives with small corrosion depths. But the effect of pit on fatigue life is gradually reduced with increasing pit size. A pit with a constant depth can be applied to the model for long exposure structure. A preliminary recommendation for the pit depth is about 1 mm for LY12CZ. At last the effect of multiple-site corrosion damage (MSCD) on fatigue life was also studied, and the result shows that MSCD can decrease substantially fatigue life compared with that of a single crack.展开更多
We theoretically investigate the effects of different electronic states as the initial state on the vortex patterns in photoelectron momentum distributions(PMDs)from numerical solutions of the two-dimensional(2D)time-...We theoretically investigate the effects of different electronic states as the initial state on the vortex patterns in photoelectron momentum distributions(PMDs)from numerical solutions of the two-dimensional(2D)time-dependent Schrodinger equation(TDSE)of He^(+)with a pair of counter-rotating circularly polarized attosecond pulses.It is found that the number of spiral arms in vortex patterns is equal to the number of the absorbed photons when the initial state is the ground state.However,the number of spiral arms in vortex patterns is always two more than the number of the absorbed photons when the initial state is the excited state.This sensitivity is attributed to the initial electron density distribution.In addition,we have demonstrated the PMDs for different initial electronic states with the same wavelengths and analyzed their corresponding physical mechanisms.It is illustrated that the method presented can be employed to effectively control the distribution of the electron vortices.展开更多
A multiple multi-qubit quantum states sharing scheme is proposed,in which the dealer can share multiple multi-qubit quantum states among the participants through only one distribution and one recovery.The dealer encod...A multiple multi-qubit quantum states sharing scheme is proposed,in which the dealer can share multiple multi-qubit quantum states among the participants through only one distribution and one recovery.The dealer encodes the secret quantum states into a special entangled state,and then distributes the particles of the entangled state to the participants.The participants perform the single-particle measurements on their particles,and can cooperate to recover the multiple multi-qubit quantum states.Compared to the existing schemes,our scheme is more efficient and more flexible in practice.展开更多
The presidential research program Brain Research through Advancing Innovative Neurotechnologies(BRAIN)Initiative was established5years ago in the United States;it has been a driving force of the United States governme...The presidential research program Brain Research through Advancing Innovative Neurotechnologies(BRAIN)Initiative was established5years ago in the United States;it has been a driving force of the United States government and private factors to promote technology development in basic and translational neuroscience research.We here summarize the research plan and recent progress in cellular neuroscience,electrical and optical engineering,chemical and systems neurobiology,and brain mapping technologies.The research plan recognizes the importance of identifying different cell populations and unknown cell types in the human brain and diseased models.Technological advances in multielectrode arrays and chemical flow measurement probes not only demonstrate the capacity of detecting neural activities in large areas,but also enable a new era of studying the neural coding information.Large-scale coordination of neuronal activity and brain mapping information will allow for the identification of therapeutic targets in neurological disorders,which is benefited by big data acquisition and analysis.Specifically,increased brain databases will expedite the dissection of thoughts,emotions,cognition,and will thereby help the development of better understanding and treatments of brain disorders.Since cell therapy demonstrates potential for regenerative medicine,the utilization of the newly advanced technologies may further improve the translational potentials and precision controls of transplanted grafts.The development of new diagnostic and therapeutic tools also requires international collaborations on science,technology,advocating,healthcare and medical ethics to advance the innovation and clinical practices.展开更多
Since China put forward the Belt and Road Initiative and a community with shared future for mankind,mainstream media in the United States such as The Washington Post,The New York Times and The Wall Street Journal have...Since China put forward the Belt and Road Initiative and a community with shared future for mankind,mainstream media in the United States such as The Washington Post,The New York Times and The Wall Street Journal have given continuous reports.As the world’s superpower,the United States has a developed media system and a wide range of influence.The study extracted 173 valid texts from May 2015 to March 2020,among which only 5 reports were on a community with shared future for mankind.American media mainly reported from five aspects including economy,politics,cultural,security and environment,although there is no lack of certain sounds,there was more negative reports.It can provide a reference basis for our accurate response and creating a positive international public opinion environment that grasping the reporting trends on the Belt and Road Initiative and a community with shared future for mankind accurately.展开更多
Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several o...Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several options of digital filter initialization have been tested with a rain storm case. It is shown that digital filter initialization, especially diabatic digital filter initialization and twice digital filter initialization, have effectively removed spurious high frequency noise from initial data for numerical weather prediction and produced balanced initial conditions. For six consecutive intermittent data assimilation cycles covering a 3-day period, mean initialization increments and impact on forecast variables are studied. DFI has been demonstrated to provide better adjustment of the hydrometeors and vertical velocity, reduced spin-up time, and improved forecast variables quantity.展开更多
基金financial support from the Fundamental Research Funds for the Central Universities of Civil Aviation University of China(No.3122024031)the Tianjin Natural Science Foundation project(No.24JCZDJC00970).
文摘The recovery stress of materials has a great potential application in the field of road crack self-repair,composite material self-repair,and so on.Taking into account the diversity of practical application environments,the recovery stresses of constrained shape memory alloy(SMA)materials in the initial state of austenite and twinned martensite are given respectively in this paper.As for the experimental research,the austenitic SMA is loaded and constrained.The recovery stresses at different stages are observed by increasing the temperature.In terms of the theoretical research,constitutive models with the initial state of austenite and martensite are established respectively based on the one-dimensional macroscopic phenomenon theoretical model and constraints of SMA.These constitutive models can describe the relationship between recovery stress and volume fraction of martensite under temperature loading with different pre-strains.The theoretical model and experimental data in this paper can provide specific support for the practical engineering application of SMA recovery stress.
基金supported by the National Key R&D Program of China(No.2022YFE0196600)the National Natural Science Foundation of China(No.52175349)the Shanghai Oriental Talent Program(No.BJKJ2024016).
文摘The impact of various initial states on the ultimate mechanical properties of medium Mn steel(MMnS)following the hot stamping process is revealed.MMnS blanks with three typical initial states were prepared separately,including hot-rolled,cold-rolled and cold-rolled and annealed(CRA).Their microstructures were observed and analyzed by scanning electron microscopy and electron backscatter diffraction,and their mechanical properties were measured by tensile tests following hot stamping and baking treatments.The results reveal that the microstructure of martensite and residual austenite characterizes the hot-stamped MMnS across different rolling conditions,with CRA state exhibiting a clearly higher residual austenite content compared to the other two states.Meanwhile,CRA state boasts not only the highest tensile strength but also the greatest elongation post-hot stamping treatment.The superior comprehensive mechanical properties are attributed to its unique biphase structure of Mn-rich austenite and Mn-poor ferrite,which emerges in CRA state following a 12 h intercritical annealing and can be partially preserved during the hot stamping process.This structure is instrumental in achieving a higher level of residual austenite,consequently leading to enhanced elongation.
基金The National Program for Support of Top-notch Young Professionalsthe Project of Global Change and Air-Sea Interaction+1 种基金the National Basic Research Program(973 Program)of China under contract No.2012CB417404the Project"Western Pacific Ocean System:Structure,Dynamics and Consequences"(WPOS)of Chinese Academy Sciences under contract No.XDA10010405
文摘The 2002/03 El Ni?o event, a new type of El Ni?o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific(CP) El Ni?o. In this study, on the basis of an El Ni?o prediction system, roles of the initial ocean surface and subsurface states on predicting the 2002/03 CP El Ni?o event are investigated to determine conditions favorable for predicting El Ni?o growth and are isolated in three sets of hindcast experiments. The hindcast is initialized through assimilation of only the sea surface temperature(SST)observations to optimize the initial surface condition(Assim_SST), only the sea level(SL) data to update the initial subsurface state(Assim_SL), or both the SST and SL data(Assim_SST+SL). Results highlight that the hindcasts with three different initial states all can successfully predict the 2002/03 El Ni?o event one year in advance and that the Assim_SST+SL hindcast performs best. A comparison between the various sets of hindcast results further demonstrates that successful prediction is significantly affected by both of the initial surface and subsurface conditions, but in different developing phases of the 2002/03 El Ni?o event. The accurate initial surface state can easier trigger the prediction of the 2002/03 El Ni?o, whereas a more reasonable initial subsurface state can contribute to improving the prediction in the growth of the warm event.
文摘The maximal evolution speed of any quantum system can be expressed by the quantum speed limit time.In this paper,we consider a model in which the system has a correlation with the environment.The influence of the initial correlation between the system and environment on the quantum speed limit is investigated.It is shown that the appearance of non-Markovianity effects causes the speedup of quantum evolution.Moreover,we demonstrate the dependence of quantum dynamical speedup on the quantum coherence of the correlated initial state.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11975132 and 61772295)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2019YQ01)Shandong Province Higher Educational Science and Technology Program,China(Grant No.J18KZ012).
文摘We investigate the correlations between two qubits in the Grover search algorithm with arbitrary initial states by numerical simulation.Using a set of suitable bases,we construct the reduced density matrix and give the numerical expression of correlations relating to the iterations.For different initial states,we obtain the concurrence and quantum discord compared with the success probability in the algorithm.The results show that the initial states affect the correlations and the limit point of the correlations in the searching process.However,the initial states do not influence the whole cyclical trend.
基金This research was supported by the National Energy Application Technology Research and Engineering Demonstration Program(NY20150101).
文摘The thermal deformation behaviors of the as-cast and wrought modified IN617 nickel-based heat-resistant alloys at different temperatures(1000–1180℃)and strain rates(0.01–1 s^(−1))were studied.The constitutive equation was established to describe the relationship of the flow stress,temperature,and strain rate during thermal deformation.The effect of the thermal deformation conditions on the microstructure evolution of alloys was studied using electron backscatter diffraction.The results revealed that the thermal deformation activation energy of the as-cast alloy was greater than that of the wrought alloy.The dynamic recrystallization(DRX)process is slow at intermediate strain rate(0.1 s^(−1))due to the comprehensive influence of various factors,such as the critical strain of DRX nucleation and stored energy.The DRX volume fraction increases with the improvement of deformation temperature.The varied dynamic softening mechanisms induce the different thermal deformation behaviors of as-cast and wrought alloys.The dynamic recovery,discontinuous dynamic recrystallization(DDRX)and nucleation at slip zone caused by strain incompatibility in grains were observed during thermal deformation of as-cast alloys.In the process of thermal deformation of wrought alloys,DDRX was the primary dynamic crystallization mechanism.The continuous dynamic recrystallization was an auxiliary nucleation mechanism.
文摘Under amplitude damping channel, the dependence of the entanglement on the initial states and , which reduce to four orthogonal Bell states if we take the parameter of states are investigated. We find that the entanglements for different initial states will decay along different curves even with the same acceleration and parame-ter of the states. We note that, in an inertial frame, the sudden death of the entanglement for will occur if , while it will not take place for for any α. We also show that the possible range of the sudden death of the entanglement for is larger than that for . There exist two groups of Bell state here we can’t distinguish only by concurrence.
基金Supported by the National Natural Science Foundation of China under Grant No 71301012
文摘A chimera state consisting of both coherent and incoherent groups is a fascinating spatial pattern in non-locally coupled identical oscillators. It is thought that random initial conditions hardly evolve to chimera states. In this work, we study the dependence of chimera states on initial conditions. We show that random initial conditions may lead to chimera states and the chance of realizing chimera states becomes increasing when the model parameters axe moving away from the boundary of their stable regime.
文摘Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.
基金support from the Beijing Computational Science Research Centersupported by the National Natural Science Foundation of China(Grant Nos.U2230402,11975050,11735005,and 11904320)。
文摘There are rich emergent phase behaviors in non-equilibrium active systems.Flocking and clustering are two representative dynamic phases.The relationship between both the phases is still unclear.Herein,we numerically investigate the evolution of flocking and clustering in a system consisting of self-propelled particles with active reorientation.We consider the interplay between flocking and clustering phases with different initial configurations,and observe a domain in steady state order parameter phase diagrams sensitive to the choice of initial configurations.Specifically,by tuning the initial degree of polar ordering,either a more ordered flocking or a disordered clustering state can be observed in the steady state.These results enlighten us to manipulate emergent behaviors and collective motions of an active system,and are qualitatively different from the emergence of a new bi-stable regime observed in aligned active particles due to an explicit attraction[New J.Phys.14073033(2012)].
文摘In January 2025,the United States issued executive orders that could potentially curtail lesbian,gay,bisexual,transgender,queer,and other sexual and gender minorities(LGBTQ+)rights and federal aid to developing countries,such as public health programs under the United States Agency for International Development(USAID)[1,2].In the Philippines,USAID has played an important role in funding and supporting initiatives to address the country’s local HIV epidemic[2,3].
文摘Extensive oedometer tests and physical tests have been conducted on remolded and reconstituted marine soils with different initial water contents and liquid limits. The oedometer test data can be well fitted with a straight line in the bilogarithmic ln(1+ e ) ~ lg p plot. The initial effective stress corresponding to the initial void ratio is determined by extrapolation of the bilogarithmic compression line. This new way of extrapolating oedometer test data to the initial void ratio overcomes the difficulty of measuring the residual effective stress of soils in the remolded state. The initial stable compression line of ocean floor deposits under different deposition environments corresponds to the compression line at the sensitivity equal to one. This initial stable compression line obtained in this study is consistent with the available compression line at the sensitivity equal to one which is proposed based on the experimental data of remolded undrained strength and the theoretical concept of Cam clay critical state line.
基金Project supported by the Qingdao National Laboratory for Marine Science and Technology(Grant No.2015ASKJ01)the National Natural Science Foundation of China(Grant Nos.11972212,12072200,and 12002213).
文摘Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,respectively.In these processes,particles involved in the avalanche grow slowly in the early stage and explosively in the later stage,which is clearly different from the continuous and steady growth trend in the monodisperse system.By examining the avalanche propagation,the number growth of particles involved in the avalanche and the slope of the number growth,the initial state can be divided into three stages:T1(nucleation stage),T2(propagation stage),T3(overall avalanche stage).We focus on the characteristics of the avalanche in the T2 stage,and find that propagation distances increase almost linearly in both axial and radial directions in polydisperse systems.We also consider the distribution characteristics of the average coordination number and average velocity for the moving particles.The results support that the polydisperse particle systems are more stable in the T2 stage.
基金Project(50675221) supported by the National Natural Science Foundation of China
文摘Based on initial discontinuity state (IDS) of material, a preliminary analytical model was presented to evaluate the effect of interaction of pitting corrosion and fatigue loading on the residual fatigue life of aluminum alloy LY12CZ. A life prediction was carried out using constant and variable amplitude loading for various pitting corrosion levels, and the prediction agreed reasonably with the available test data. The results suggest that the combination of a pit and IDS can be treated as the initial crack size. Pitting corrosion causes a significant decrease in fatigue lives with small corrosion depths. But the effect of pit on fatigue life is gradually reduced with increasing pit size. A pit with a constant depth can be applied to the model for long exposure structure. A preliminary recommendation for the pit depth is about 1 mm for LY12CZ. At last the effect of multiple-site corrosion damage (MSCD) on fatigue life was also studied, and the result shows that MSCD can decrease substantially fatigue life compared with that of a single crack.
基金Project supported by the National Natural Science Foundation of China(Grant No.12074142)the Natural Science Foundation of Jilin Province of China(Grant No.20180101225JC)the Graduate Innovation Fund of Jilin University,China(Grant No.101832020CX337)。
文摘We theoretically investigate the effects of different electronic states as the initial state on the vortex patterns in photoelectron momentum distributions(PMDs)from numerical solutions of the two-dimensional(2D)time-dependent Schrodinger equation(TDSE)of He^(+)with a pair of counter-rotating circularly polarized attosecond pulses.It is found that the number of spiral arms in vortex patterns is equal to the number of the absorbed photons when the initial state is the ground state.However,the number of spiral arms in vortex patterns is always two more than the number of the absorbed photons when the initial state is the excited state.This sensitivity is attributed to the initial electron density distribution.In addition,we have demonstrated the PMDs for different initial electronic states with the same wavelengths and analyzed their corresponding physical mechanisms.It is illustrated that the method presented can be employed to effectively control the distribution of the electron vortices.
文摘A multiple multi-qubit quantum states sharing scheme is proposed,in which the dealer can share multiple multi-qubit quantum states among the participants through only one distribution and one recovery.The dealer encodes the secret quantum states into a special entangled state,and then distributes the particles of the entangled state to the participants.The participants perform the single-particle measurements on their particles,and can cooperate to recover the multiple multi-qubit quantum states.Compared to the existing schemes,our scheme is more efficient and more flexible in practice.
文摘The presidential research program Brain Research through Advancing Innovative Neurotechnologies(BRAIN)Initiative was established5years ago in the United States;it has been a driving force of the United States government and private factors to promote technology development in basic and translational neuroscience research.We here summarize the research plan and recent progress in cellular neuroscience,electrical and optical engineering,chemical and systems neurobiology,and brain mapping technologies.The research plan recognizes the importance of identifying different cell populations and unknown cell types in the human brain and diseased models.Technological advances in multielectrode arrays and chemical flow measurement probes not only demonstrate the capacity of detecting neural activities in large areas,but also enable a new era of studying the neural coding information.Large-scale coordination of neuronal activity and brain mapping information will allow for the identification of therapeutic targets in neurological disorders,which is benefited by big data acquisition and analysis.Specifically,increased brain databases will expedite the dissection of thoughts,emotions,cognition,and will thereby help the development of better understanding and treatments of brain disorders.Since cell therapy demonstrates potential for regenerative medicine,the utilization of the newly advanced technologies may further improve the translational potentials and precision controls of transplanted grafts.The development of new diagnostic and therapeutic tools also requires international collaborations on science,technology,advocating,healthcare and medical ethics to advance the innovation and clinical practices.
基金Postgraduate Innovation Program of Jiangsu Province in 2020:research on the construction of a community of shared future for mankind from the perspective of Marx’s thoery of world history(KYCX20_3060)Key projects in 2017 of The National Social Science Fund of China“The spread of Chinese traditional elementary school among countries in‘the Belt and Road Initiative’”(No.17AZS012)Teaching reform and research topics of Jiangsu University“Research on the construction of the mixed teaching mode of‘Internet+ideological and political courses’”(No.2019JGZD014)。
文摘Since China put forward the Belt and Road Initiative and a community with shared future for mankind,mainstream media in the United States such as The Washington Post,The New York Times and The Wall Street Journal have given continuous reports.As the world’s superpower,the United States has a developed media system and a wide range of influence.The study extracted 173 valid texts from May 2015 to March 2020,among which only 5 reports were on a community with shared future for mankind.American media mainly reported from five aspects including economy,politics,cultural,security and environment,although there is no lack of certain sounds,there was more negative reports.It can provide a reference basis for our accurate response and creating a positive international public opinion environment that grasping the reporting trends on the Belt and Road Initiative and a community with shared future for mankind accurately.
基金National Natural Science Foundation of China (40675020)
文摘Initialization and initial imbalance problem were discussed in the context of a three-dimensional variational data assimilation system of the new generation"Weather Research and Forecasting Model". Several options of digital filter initialization have been tested with a rain storm case. It is shown that digital filter initialization, especially diabatic digital filter initialization and twice digital filter initialization, have effectively removed spurious high frequency noise from initial data for numerical weather prediction and produced balanced initial conditions. For six consecutive intermittent data assimilation cycles covering a 3-day period, mean initialization increments and impact on forecast variables are studied. DFI has been demonstrated to provide better adjustment of the hydrometeors and vertical velocity, reduced spin-up time, and improved forecast variables quantity.