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FLOCKING OF A THERMODYNAMIC CUCKER-SMALE MODEL WITH LOCAL VELOCITY INTERACTIONS
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作者 金春银 李双智 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期632-649,共18页
In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on pe... In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on perturbations of a linearized system, we provide a sufficient framework in terms of initial data and model parameters to guarantee flocking. Moreover, it is shown that the system achieves a consensus at an exponential rate. 展开更多
关键词 FLOCKING local interaction thermodynamical Cucker-Smale model stochastic matrix neighbor graph
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Effect of the sloping seabed on 3D soil-spudcan interaction using a material point-finite element(MPM-FEM)model
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作者 Zhengda Lei Guangtian Zeng +2 位作者 Huaihui Ren Bisheng Wu Yuxin Jie 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1436-1454,共19页
The sloping seabed affects the bearing capacity and failure mechanism of soil,which may compromise the stability and safety of offshore structures such as jack-up platforms.This paper employs a coupled model combining... The sloping seabed affects the bearing capacity and failure mechanism of soil,which may compromise the stability and safety of offshore structures such as jack-up platforms.This paper employs a coupled model combining the material point method and finite element method(MPM-FEM)to analyze the impact of sloping seabeds on the three-dimensional soil-spudcan interaction.The MPM-FEM model implements the B¯approach to solve the challenge of volumetric locking due to the incompressibility constraints imposed by yield criterion.It is validated against the centrifuge results.The effects of sloping seabeds on penetration resistance,soil flow pattern,lateral response,stress distribution,and failure mechanism are discussed.The soil mainly undergoes overall failure when the ratio of penetration depth to spudcan diameter(i.e.D P/D)is between 0 and 0.25.As the slope angle increases,the soil on the side of lower slope is expelled further,resulting in an asymmetric stress distribution and a larger horizontal sliding force of soil.When D P/D increases to 0.75,the soil transitions to localized plastic flow failure,and the range of soil flow affected by the spudcan penetration decreases.The results show that,when the slope angle increases,the lateral displacement and stress distribution on the lower slope of a sloping seabed is significantly larger than that of a horizontal seabed,impacting the spudcan and surrounding soil behavior.The study suggests that the seabed slope significantly affects the range of soil flow and failure at shallow penetration,indicating that the slope angle should be taken into account in the design and installation of offshore jack-up rigs,particularly in areas with sloping seabeds. 展开更多
关键词 Soil-spudcan interaction Centrifuge tests MPM-FEM model B—approach Sloping seabeds Offshore structures
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Comparison of Pile-Soil-Structure Interaction Modeling Techniques for A 10-MW Large-Scale Monopile Wind Turbine Model Under Wind and Wave Conditions
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作者 ZENG Yu-xin ZHANG Xiao-ming +3 位作者 ZHANG Li-xian SHI Wei WANG Wen-hua LI Xin 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期471-483,共13页
Considering the large diameter effect of piles,the influence of different pile-soil analysis methods on the design of monopile foundations for offshore wind turbines has become an urgent problem to be solved.Three dif... Considering the large diameter effect of piles,the influence of different pile-soil analysis methods on the design of monopile foundations for offshore wind turbines has become an urgent problem to be solved.Three different pile-soil models were used to study a large 10 MW monopile wind turbine.By modeling the three models in the SACS software,this paper analyzed the motion response of the overall structure under the conditions of wind and waves.According to the given working conditions,this paper concludes that under the condition of independent wind,the average value of the tower top x-displacement of the rigid connection method is the smalle st,and the standard deviation is the smallest under the condition of independent wave.The results obtained by the p-y curve method are the most conservative. 展开更多
关键词 large-scale monopile offshore wind turbine pile-soil model wind-wave load combination
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Parameter calibration of the tensile-shear interactive damage constitutive model for sandstone failure
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作者 Yun Shu Zheming Zhu +4 位作者 Meng Wang Weiting Gao Fei Wang Duanying Wan Yuntao Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1153-1174,共22页
The tensile-shear interactive damage(TSID)model is a novel and powerful constitutive model for rock-like materials.This study proposes a methodology to calibrate the TSID model parameters to simulate sandstone.The bas... The tensile-shear interactive damage(TSID)model is a novel and powerful constitutive model for rock-like materials.This study proposes a methodology to calibrate the TSID model parameters to simulate sandstone.The basic parameters of sandstone are determined through a series of static and dynamic tests,including uniaxial compression,Brazilian disc,triaxial compression under varying confining pressures,hydrostatic compression,and dynamic compression and tensile tests with a split Hopkinson pressure bar.Based on the sandstone test results from this study and previous research,a step-by-step procedure for parameter calibration is outlined,which accounts for the categories of the strength surface,equation of state(EOS),strain rate effect,and damage.The calibrated parameters are verified through numerical tests that correspond to the experimental loading conditions.Consistency between numerical results and experimental data indicates the precision and reliability of the calibrated parameters.The methodology presented in this study is scientifically sound,straightforward,and essential for improving the TSID model.Furthermore,it has the potential to contribute to other rock constitutive models,particularly new user-defined models. 展开更多
关键词 Damage constitutive model Parameter calibration Rock modeling SANDSTONE Dynamic impact load Tensile-shear interactive damage(TSID)model
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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation
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作者 Zhao-yang Yin Qi-chi Le +3 位作者 Yan-chao Jiang Da-zhi Zhao Qi-yu Liao Qi Zou 《China Foundry》 SCIE EI CAS CSCD 2024年第1期29-43,共15页
A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the u... A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in detail.Additionally,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct ultrasounds.As a result,various acoustic pressure distributions and cavitation regions are obtained.The spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical rods.Increasing the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution pattern.The acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20). 展开更多
关键词 dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy
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Chemical simulation teaching system based on virtual reality and gesture interaction
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作者 Dengzhen LU Hengyi LI +2 位作者 Boyu QIU Siyuan LIU Shuhan QI 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期148-168,共21页
Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based ... Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education. 展开更多
关键词 Chemical experiment simulation Gesture interaction Virtual reality model establishment Process control Streaming media DATABASE
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Dark Galaxies, Sun-Earth-Moon Interaction, Tunguska Event—Explained by WUM
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期836-853,共18页
Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fa... Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fact, an object the size of a galaxy, made entirely of dark matter. They found that the speed of the Earth’s rotation varies randomly each day. 115 years ago, the Tunguska Event was observed, and astronomers still do not have an explanation of It. Main results of the present article are: 1) Dark galaxies explained by the spinning of their Dark Matter Cores with the surface speed at equator less than the escape velocity. Their Rotational Fission is not happening. Extrasolar systems do not emerge;2) 21-cm Emission explained by the self-annihilation of Dark Matter particles XIONs (5.3 μeV);3) Sun-Earth-Moon Interaction explained by the influence of the Sun’s and the Moon’s magnetic field on the electrical currents of the charged Geomagma (the 660-km layer), and, as a result, the Earth’s daylength varies;4) Tunguska Event explained by a huge atmospheric explosion of the Superbolide, which was a stable Dark Matter Bubble before entering the Earth’s atmosphere. 展开更多
关键词 World-Universe model Dark Stars Dark Galaxies 21-cm Emission Formation of Macrostructures Sun-Earth-Moon interaction Tunguska Event Dark Matter
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Modeling One Dimensional Two-Cell Model with Tumor Interaction Using Krylov Subspace Methods
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作者 Ibtisam Alqahtani Sharefa Eisa Ali Alhazmi 《Applied Mathematics》 2023年第1期21-34,共14页
A brain tumor occurs when abnormal cells grow, sometimes very rapidly, into an abnormal mass of tissue. The tumor can infect normal tissue, so there is an interaction between healthy and infected cell. The aim of this... A brain tumor occurs when abnormal cells grow, sometimes very rapidly, into an abnormal mass of tissue. The tumor can infect normal tissue, so there is an interaction between healthy and infected cell. The aim of this paper is to propose some efficient and accurate numerical methods for the computational solution of one-dimensional continuous basic models for the growth and control of brain tumors. After computing the analytical solution, we construct approximations of the solution to the problem using a standard second order finite difference method for space discretization and the Crank-Nicolson method for time discretization. Then, we investigate the convergence behavior of Conjugate gradient and generalized minimum residual as Krylov subspace methods to solve the tridiagonal toeplitz matrix system derived. 展开更多
关键词 PDES Krylov Subspace Methods Finite Difference Toeplitz Matrix Two-Cell model Tumor interaction modeling
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Analysis of Commuting Modal Shift in Consideration of Social Interaction of Consciousness for Environment
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作者 Masashi Okushima 《Journal of Traffic and Transportation Engineering》 2024年第2期63-80,共18页
It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but ... It is the matter for achievement of the low carbon transport system that the excessive use of private vehicles can be controlled appropriately.Not only improvement of service level of modes except private vehicle,but also consciousness for environmental problem of individual trip maker is important for eco-commuting promotion.On the other hand,consciousness for environment would be changed by influence of other person.Accordingly,it is aimed in the study that the structure of decision-making process for modal shift to the eco-commuting mode in the local city is described considering environmental consciousness and social interaction.For the purpose,the consciousness for the environment problem and the travel behavior of the commuter at the suburban area in the local city are investigated by the questionnaire survey.The covariance structure about the eco-consciousness is analyzed with the database of the questionnaire survey by structural equation modeling.As the result,it can be confirmed with the structural equation model that the individual environmental consciousness is strongly related with the intention of self-sacrifice and is influenced with the local interaction of the individual connections.On the other hand,the intention of modal shift for the commuting mode is analyzed with the database of the questionnaire survey.It can be found out that the environmental consciousness is not statistically significant for commuting mode choice with the present poor level of service of public transport.However,the intention of self-sacrifice for the prevention of the global warming is statistically confirmed as the factor of modal shift with the operation of eco-commuting bus service with the RP/SP integrated estimation method.As the result,the multi-agent simulation system with social interaction model for eco consciousness is developed to measure the effect of the eco-commuting promotion.For the purpose,the carbon dioxide emission is estimated based on traffic demand and road network condition in the traffic environment model.On the other hand,the relation between agents is defined based on the small world network.The proposed multi-agent simulation is applied to measure the effect of the eco-commuting promotion such as improvement of level of service on the public transport or education of eco-consciousness.The effect of the promotion plan can be observed with the proposed multi-agent system.Finally,it can be concluded that the proposed multi-agent simulation with social interaction for eco-consciousness is useful for planning of eco-commuting promotion. 展开更多
关键词 Greenhouse gas emission modal shift structural equation model RP/SP combined estimation multi-agent simulation local interaction small world network consciousness for environment commuting shuttle bus local city
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Designing Artemisinins with Antimalarial Potential, Combining Molecular Electrostatic Potential, Ligand-Heme Interaction and Multivariate Models
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作者 Josué de Jesus Oliveira Araújo Ricardo Morais de Miranda +10 位作者 Jeferson Stiver Oliveira de Castro Antonio Florêncio de Figueiredo Ana Cecília Barbosa Pinheiro Sílvia Simone dos Santos Morais Marcos Antonio Barros dos Santos Andréia de Lourdes Ribeiro Pinheiro Andréia de Lourdes Ribeiro Pinheiro Fábio dos Santos Gil Heriberto Rodrigues Bitencourt Gustavo Nery Ramos Alves José Ciríaco Pinheiro 《Computational Chemistry》 CAS 2023年第1期1-23,共23页
Artemisinins tested against W-2 strains of malaria falciparum are investigated with molecular electrostatic potential (MEP), in an attempt to identify key features of the compounds that are necessary for their activit... Artemisinins tested against W-2 strains of malaria falciparum are investigated with molecular electrostatic potential (MEP), in an attempt to identify key features of the compounds that are necessary for their activities, as well as to investigate likely interactions with the receptor in a biological process and to use that information to propose new molecules. In order to discover the best geometry involving the ligand-receptor complexes (heme) studied and help in the proposition of the new derivatives, molecular simulations of interactions between the most negative charged region around the peroxide and heme locates (the ones around the Fe2+ ion) were carried out. In addition, PCA (principal components analysis), HCA (hierarchical cluster analysis), SDA (stepwise discriminant analysis), and KNN (K-nearest neighbor) multivariate models were employed to investigate which descriptors are responsible for the classification between the higher and lower antimalarial activity of the compounds, and also this information was used to propose new potentially active molecules. The information accumulated in studies of MEP, molecular docking, and multivariate analysis supported the proposal of new structures with potential antimalarial activities. The multivariate models constructed were applied to the new structures and indicated numbers 19 and 20 as the most prominent for syntheses and biological assays. 展开更多
关键词 ARTEMISININS Antimalarial Potential Molecular Electrostatic Potential Ligand-Heme interaction Multivariate models
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Wheel-rail contact model for railway vehicle-structure interaction applications:development and validation
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作者 P.A.Montenegro R.Calçada 《Railway Engineering Science》 2023年第3期181-206,共26页
An enhancement in the wheel-rail contact model used in a nonlinear vehicle-structure interaction(VSI)methodology for railway applications is presented,in which the detection of the contact points between wheel and rai... An enhancement in the wheel-rail contact model used in a nonlinear vehicle-structure interaction(VSI)methodology for railway applications is presented,in which the detection of the contact points between wheel and rail in the concave region of the thread-flange transition is implemented in a simplified way.After presenting the enhanced formulation,the model is validated with two numerical applications(namely,the Manchester Benchmarks and a hunting stability problem of a sus-pended wheelset),and one experimental test performed in a test rig from the Railway Technical Research Institute(RTRI)in Japan.Given its finite element(FE)nature,and contrary to most of the vehicle multibody dynamic commercial software that cannot account for the infrastructure flexibility,the proposed VSI model can be easily used in the study of train-bridge systems with any degree of complexity.The validation presented in this work proves the accuracy of the proposed model,making it a suitable tool for dealing with different railway dynamic applications,such as the study of bridge dynamics,train running safety under different scenarios(namely,earthquakes and crosswinds,among others),and passenger riding comfort. 展开更多
关键词 Vehicle-structure interaction Wheel-rail contact Manchester Benchmarks Thread-flange transition Dynamic analysis model validation
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Particles Composition and Interactions Using the Nuon Model
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作者 René Brun 《Journal of Modern Physics》 CAS 2023年第5期623-665,共43页
The Standard Model in Particle Physics has been able to make many predictions confirmed later with a flow of experimental results. With the discovery of the Higgs boson at the LHC, one is full of admiration for the pe... The Standard Model in Particle Physics has been able to make many predictions confirmed later with a flow of experimental results. With the discovery of the Higgs boson at the LHC, one is full of admiration for the people contributing to this model fifty years ago and its predictions that have been confirmed gradually. The original particle quark constituent model has evolved with the deep inelastic experiments to a quark and gluons system, then to a more general system with virtual quarks. This work is the result of observations while working at CERN in Geneva with many different experiments at the ISR, SPS, LEP, LHC colliders. A new model based on nuons is introduced, that allows accurate evaluations of the particle masses (mesons and baryons) and magnetic moment, computes very accurately the kinematics distributions for particles and jets observed in the p-p collisions at the LHC (elastic and inelastic) and at lower energy machines. This new model looks at a first glance in contradiction with the quark model because it can build the elementary particles with nuons only, i.e. electrons and neutrinos. However, all the existing physics involved in electron, positron and neutrino interactions may be used to explain interactions between composite particles such as protons or heavy ions. 展开更多
关键词 Standard model Particle Masses Particles interactions Elastic Scattering Deep Inelastic Jets Charge Density
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Design of N-11-Azaartemisinins Potentially Active against Plasmodium falciparum by Combined Molecular Electrostatic Potential, Ligand-Receptor Interaction and Models Built with Supervised Machine Learning Methods
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作者 Jeferson Stiver Oliveira de Castro José Ciríaco Pinheiro +5 位作者 Sílvia Simone dos Santos de Morais Heriberto Rodrigues Bitencourt Antonio Florêncio de Figueiredo Marcos Antonio Barros dos Santos Fábio dos Santos Gil Ana Cecília Barbosa Pinheiro 《Journal of Biophysical Chemistry》 CAS 2023年第1期1-29,共29页
N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning m... N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning methods (PCA, HCA, KNN, SIMCA, and SDA). The optimization of molecular structures was performed using the B3LYP/6-31G* approach. MEP maps and ligand-receptor interactions were used to investigate key structural features required for biological activities and likely interactions between N-11-azaartemisinins and heme, respectively. The supervised machine learning methods allowed the separation of the investigated compounds into two classes: cha and cla, with the properties ε<sub>LUMO+1</sub> (one level above lowest unoccupied molecular orbital energy), d(C<sub>6</sub>-C<sub>5</sub>) (distance between C<sub>6</sub> and C<sub>5</sub> atoms in ligands), and TSA (total surface area) responsible for the classification. The insights extracted from the investigation developed and the chemical intuition enabled the design of sixteen new N-11-azaartemisinins (prediction set), moreover, models built with supervised machine learning methods were applied to this prediction set. The result of this application showed twelve new promising N-11-azaartemisinins for synthesis and biological evaluation. 展开更多
关键词 Antimalarial Design MEP Ligand-Receptor interaction Supervised Machine Learning Methods models Built with Supervised Machine Learning Methods
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Dynamic Analysis of the Seafloor Pilot Miner Based on Single-Body Vehicle Model and Discretized Track-Terrain Interaction Model 被引量:5
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作者 戴瑜 刘少军 李力 《China Ocean Engineering》 SCIE EI 2010年第1期145-160,共16页
In order to achieve the complex dynamic analysis of the self-propelled seafloor pilot miner moving on the seafloor of extremely cohesive soft soil and further to make it possible to integrate the miner system with som... In order to achieve the complex dynamic analysis of the self-propelled seafloor pilot miner moving on the seafloor of extremely cohesive soft soil and further to make it possible to integrate the miner system with some subsystems to form the complete integrated deep ocean mining pilot system and perform dynamic analysis, a new method for the dynamic modeling and analysis of the miner is proposed and developed in this paper, resulting in a simplified 3D single-body vehicle model with three translational and three rotational degrees of freedom, while the track-terrain interaction model is built by partitioning the track-terrain interface into discrete elements with parameterized force dements built on the theory of terramechanics acting on each discrete dement. To evaluate and verify the correctness and effectiveness of this new modeling and analysis method, typical comparative studies with regard to computational efficiency and solution accuracy are carried out between the traditional modeling method of building the tracked vehicle as a multi-body model and the new modeling method. In full consideration of the particMar structure design of the pilot miner, the special characteristics of the seafioor soil and the hydrodynamic force of near-seafloor currnt, the dynamic simulation analysis of the miner is performed and discussed, which can provide useful guidance and reference for the practical miner system in design and operation. This new method can not only realize the rapid dynamic simulation analysis of the miner but also make possible the integration and rapid dynamic analysis of the complete integrated deep ocean mining pilot system in further researches. 展开更多
关键词 deep-ocean mining system self-propelled seafloor pilot miner single-body model multi-body model discretized track-terrain interaction model dynamic analysis
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INTERACTION MODELS FOR EFFECTIVE THERMAL AND ELECTRIC CONDUCTIVITIES OF CARBON NANOTUBE COMPOSITES 被引量:6
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作者 Fei Deng Quanshui Zheng 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第1期1-17,共17页
The present article provides supplementary information of previous works of analytic models for predicting conductivity enhancements of carbon nanotube composites. The models, though fairly simple, are able to take ac... The present article provides supplementary information of previous works of analytic models for predicting conductivity enhancements of carbon nanotube composites. The models, though fairly simple, are able to take account of the effects of conductivity anisotropy, nonstraightness, and aspect ratio of the CNT additives on the conductivity enhancement of the composite and to give predictions agreeing well with existing experimental data. The omitted detailed derivation of this model is demonstrated in the present article with a more systematical analysis, which may help with further development in this direction. Furthermore, the effects of various orientation distributions of CNTs are reported here for the first time. The information may be useful in design or fabrication technology of CNT composites for better or specified conductivities. 展开更多
关键词 thermal conductivity electric conductivity carbon nanotube composite interaction effective models
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Maximal and total skew information for a two-qubit system using nonlinear interaction models 被引量:7
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作者 孙红贵 刘万芳 李春杰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期37-43,共7页
Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemen... Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemented in three nonlinear interaction models with an external field, we give the exact state vectors and the expectation value (Sz) at any time t. Based on (Sz)2, we give the maximal and the total skew information and a condition in which the maximal and the total skew information can reach 1 and 2, respectively. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models two-qubit system
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Maximal and total skew information of three-qubit system obtained using nonlinear interaction models 被引量:6
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作者 孙红贵 章礼华 +1 位作者 刘万芳 李春杰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期52-61,共10页
Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the ... Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the maximal and the total skew information. It is found that they have the same form and their evolution periods are dependent on the energy difference between the ground state and the second excited state in these models. The maximal skew information is always in the (Sx, Sv) plane. We give the condition for the occurrence of IGHZ}sy, in which they can reach the extreme values of 9/4 and 15/4, respectively. In three different decoherence channels, two kinds of information and the concurrence are calculated. We find that the phenomenon of the concurrence of sudden death occurs, but the above two kinds of information do not die suddenly. In the phase-damping channel, the two kinds of information will not be lost completely. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models three-qubit system three decoherenee channels
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The superiority of multi-trait models with genotype-by-environment interactions in a limited number of environments for genomic prediction in pigs 被引量:6
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作者 Hailiang Song Qin Zhang Xiangdong Ding 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第1期207-219,共13页
Background: Different production systems and climates could lead to genotype-by-environment(G × E) interactions between populations, and the inclusion of G × E interactions is becoming essential in breeding ... Background: Different production systems and climates could lead to genotype-by-environment(G × E) interactions between populations, and the inclusion of G × E interactions is becoming essential in breeding decisions. The objective of this study was to investigate the performance of multi-trait models in genomic prediction in a limited number of environments with G × E interactions.Results: In total, 2,688 and 1,384 individuals with growth and reproduction phenotypes, respectively, from two Yorkshire pig populations with similar genetic backgrounds were genotyped with the PorcineSNP80 panel.Single-and multi-trait models with genomic best linear unbiased prediction(GBLUP) and BayesC π were implemented to investigate their genomic prediction abilities with 20 replicates of five-fold cross-validation.Our results regarding between-environment genetic correlations of growth and reproductive traits(ranging from 0.618 to 0.723) indicated the existence of G × E interactions between these two Yorkshire pig populations. For single-trait models, genomic prediction with GBLUP was only 1.1% more accurate on average in the combined population than in single populations, and no significant improvements were obtained by BayesC π for most traits. In addition, single-trait models with either GBLUP or BayesC π produced greater bias for the combined population than for single populations. However, multi-trait models with GBLUP and BayesC π better accommodated G × E interactions,yielding 2.2% – 3.8% and 1.0% – 2.5% higher prediction accuracies for growth and reproductive traits, respectively,compared to those for single-trait models of single populations and the combined population. The multi-trait models also yielded lower bias and larger gains in the case of a small reference population. The smaller improvement in prediction accuracy and larger bias obtained by the single-trait models in the combined population was mainly due to the low consistency of linkage disequilibrium between the two populations, which also caused the BayesC π method to always produce the largest standard error in marker effect estimation for the combined population.Conclusions: In conclusion, our findings confirmed that directly combining populations to enlarge the reference population is not efficient in improving the accuracy of genomic prediction in the presence of G × E interactions, while multi-trait models perform better in a limited number of environments with G × E interactions. 展开更多
关键词 Combined population Genotype-by-environment interaction Linkage disequilibrium Multi-trait model PIG
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A NOTE ON THE INTERACTIONS OF ELEMENTARY WAVES FOR THE AR TRAFFIC FLOW MODEL WITHOUT VACUUM 被引量:3
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作者 孙梅娜 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1503-1512,共10页
In this note, we consider the interactions of elementary waves for the traffic flow model proposed by Aw and Rascle when the vacuum is not involved. The solutions are obtained constructively and globally when the init... In this note, we consider the interactions of elementary waves for the traffic flow model proposed by Aw and Rascle when the vacuum is not involved. The solutions are obtained constructively and globally when the initial data consist of three pieces of constant states. Furthermore, it can be found that the Riemann solutions are stable with respect to such small perturbations of the initial data in this particular situation by investigating the limits of the solutions as the perturbed parameter ε goes to zero. 展开更多
关键词 interaction of elementary wave Aw-Rascle model Riemann problem traffic flow hyperbolic conservation laws
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THE AVALANCHE DYNAMICS IN RANDOM NEAREST NEIGHBOR MODELS OF EVOLUTION WITH INTERACTION STRENGTH 被引量:2
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作者 贾武 范文涛 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期179-187,共9页
A generalized Bak-Sneppen model (BS model) of biological evolution with intcraction strength θ is introduced in d-dimensional space, where the “nearest neighbors” are chosen among the 2d neighbors of the extremal... A generalized Bak-Sneppen model (BS model) of biological evolution with intcraction strength θ is introduced in d-dimensional space, where the “nearest neighbors” are chosen among the 2d neighbors of the extremal site, with the probabilities rebated to the sizes of the fitnesses. Simulations of one- and two-dimensional models arc given.For given θ 〉 0, the model can self-organize, to a critical state, and the critical threshold fc(θ) decreases as θ increases. The exact gap equation depending on θ is presented, which reduces to the gap equation of BS model as θ tends to infinity. An exact cquation for the critical exponent γ(θ) is also obtained. Scaling relations are established among the six critical exponents of the avalanches of the model. 展开更多
关键词 BS model interaction strength gap equation AVALANCHE critical exponent
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