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Isospin- and momentum-dependent interaction in isospin-dependent quantum molecular dynamics 被引量:1
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作者 刘建业 郭文军 +3 位作者 任中洲 邢永忠 左维 李希国 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1738-1745,共8页
An isospin-dependent quantum molecular dynamical model (IQMD) is developed, with the isospin degree of freedom in the momentum-dependent interaction(MDI) included in IQMD, to obtain an isospin- and momentum-depend... An isospin-dependent quantum molecular dynamical model (IQMD) is developed, with the isospin degree of freedom in the momentum-dependent interaction(MDI) included in IQMD, to obtain an isospin- and momentum-dependent interaction (IMDI) in IQMD. We investigate the effect of IMDI on the isospin fractionation ratio and its dynamical mechanism in the intermediate energy heavy ion collisions. It is found that the IMDI induces the significant reductions in the isospin fractionation ratio for all of beam energies, impact parameters, neutron-proton ratios and mass number of colliding systems. However, the strong dependence of isospin fractionation ratio on the symmetrical potential is preserved, with the isospin degree of freedom included in the MDI, i.e. the isospin fractionation ratio is still a good probe for extracting the information about the equation of state of isospin asymmetrical nuclear matter. 展开更多
关键词 heavy ion collision isospin fractionation ratio isospin and momentum dependent interaction isospin effect
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Role of Parallel Tempering Monte Carlo Simulation in 2D Ising Spin Glass System with Distance Dependent Interaction 被引量:1
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作者 Habte Dulla Berry Pooran Singh 《Journal of Physical Science and Application》 2012年第7期216-223,共8页
Spin glass system is a complex disordered system with a number of local minima separated by entropic barriers. Therefore, parallel tempering Monte Carlo simulation was used in order to get fast thermalisation (to min... Spin glass system is a complex disordered system with a number of local minima separated by entropic barriers. Therefore, parallel tempering Monte Carlo simulation was used in order to get fast thermalisation (to minimize the relaxation time). Distance dependent interaction coupling in 2D is studied in order to show how a spin glass phase transition occurs when couplings between far away spins are permitted by considering Edwards-Anderson Ising spin glass model. The interaction coupling is a quenched random variable whose probability of being non-zero decays with distance between two spin sites rij = |i-j|mod(L/2).The interaction coupling is random and its probability distribution is decaying with the distance between the spins (p(Jij) αrij^-ρ). The model is studied by changing p among three different regimes (p 〉 2D, 4/3 D〈 p 〈 2D, p 〈 4/3D). A phase transition temperature for p = 2, 3, 4 is obtained. 展开更多
关键词 Parallel tempering Monte Carlo method thermalisation spin glass system distance dependent interaction coupling andphase transition.
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Quark Model Approach to the Charge Dependent N-N Interaction
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作者 Xu, Pu Zong, Hongshi +2 位作者 Ping, Jialun Wang, Fan He, Hanxin 《Chinese journal of nuclear physics》 EI 1997年第3期147-154,共8页
The N-N <sup>1</sup>S<sub>0</sub> scattering length differences Δα<sub>CSB</sub> and Δα<sub>CIH</sub> of the charge symmetrybreaking and charge independence breaking... The N-N <sup>1</sup>S<sub>0</sub> scattering length differences Δα<sub>CSB</sub> and Δα<sub>CIH</sub> of the charge symmetrybreaking and charge independence breaking are calculated by a resonating group method with aquark cluster model.By adding the QED-QCD interference effect to the quark mass differenceand the electromagnetic interaction,the Δα<sub>CSH</sub> and Δα<sub>CIH</sub> can be reproduced with modelparameters constrained by the hadron isomultiplet masses. 展开更多
关键词 QED-QCD interference effect CHARGE dependence N-N interaction Quark cluster model
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Relativistic symmetry of position-dependent mass particles in a Coulomb field including tensor interaction
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作者 M.Eshghi M.Hamzavi S.M.Ikhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期122-128,共7页
The spatially-dependent mass Dirac equation is solved exactly for attractive scalar and repulsive vector Coulomb potentials,including a tensor interaction under the spin and pseudospin symmetric limits.Closed forms of... The spatially-dependent mass Dirac equation is solved exactly for attractive scalar and repulsive vector Coulomb potentials,including a tensor interaction under the spin and pseudospin symmetric limits.Closed forms of the energy eigenvalue equation and wave functions are obtained for arbitrary spin-orbit quantum number κ.Some numerical results are also given,and the effect of tensor interaction on the bound states is presented.It is shown that tensor interaction removes the degeneracy between two states in the spin doublets.We also investigate the effects of the spatially-dependent mass on the bound states under spin symmetric limit conditions in the absence of tensor interaction. 展开更多
关键词 Dirac equation spin and pseudospin symmetries spatially-dependent mass tensor interaction
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Nonlinear parametric interactions in ion-implanted semiconductor plasmas having strain-dependent dielectric constants
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作者 N Yadav S Ghosh P S Malviya 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期304-309,共6页
We report nonlinear parametric interactions using a hydrodynamic model of ion-implanted semiconductor plasmas having strain-dependent dielectric constants(SDDC). High-dielectric-constant materials are technologicall... We report nonlinear parametric interactions using a hydrodynamic model of ion-implanted semiconductor plasmas having strain-dependent dielectric constants(SDDC). High-dielectric-constant materials are technologically important because of their nonlinear properties. We find that the third-order susceptibility varies in the range 10^-14--10^-12m^2·V^-2 for ion-implanted semiconductor plasmas, which is in good agreement with previous results. It is found that the presence of SDDC in ion-implanted semiconductor plasma modifies the characteristic properties of the material. 展开更多
关键词 nonlinear parametric interactions ion-implanted semiconductor plasmas strain-dependent dielectric constant
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Feedback regulation between phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1 and transforming growth factor β1 and prognostic value in gastric cancer 被引量:3
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作者 Qi Shao Zhi-Ming Chen 《World Journal of Gastroenterology》 SCIE CAS 2020年第1期21-34,共14页
BACKGROUND Phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1(PREX1)was reported to be overexpressed in some cancers and involved in cancer development,but its expression and significance in gast... BACKGROUND Phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1(PREX1)was reported to be overexpressed in some cancers and involved in cancer development,but its expression and significance in gastric cancer remain unclear.AIM To evaluate the expression of PREX1 in gastric cancer and its significance in the development of gastric cancer,especially to evaluate the potential mechanism of PREX1 in gastric cancer.METHODS Bioinformatic analysis was performed in order to examine the expression of PREX1 in gastric cancer.The relationship between the survival rate of gastric cancer patients and PREX1 expression was assessed by Kaplan Meier portal.The Gene Set Enrichment Analysis and the correlation between PREX1 and transforming growth factor(TGF)β1 pathway-related mediators were evaluated by cBioPortal for Cancer Genomics.Western blotting and reverse transcriptase polymerase chain reaction assay were used to test the role of TGFβ1 on the expression of PREX1.Western blotting and dual-luciferase reporter system was used to evaluate the effect of PREX1 on the activation of TGFβ1 pathway.Wound healing and Transwell assay were used to assess the effect of PREX1 on the metastasis activity of gastric cancer cells.RESULTS PREX1 was overexpressed in the gastric tumors,and the expression levels were positively associated with the development of gastric cancer.Also,the high expression of PREX1 revealed poor prognosis,especially for those advanced and specific intestinal gastric cancer patients.PREX1 was closely involved in the positive regulation of cell adhesion and positively correlated with TGFβ1-related mediators.Furthermore,TGFβ1 could induce the expression of PREX1 at both the protein and mRNA level.Also,PREX1 could activate the TGFβ1 pathway.The induced PREX1 could increase the migration and invasion activity of gastric cancer cells.CONCLUSION PREX1 is overexpressed in gastric cancer,and the high level of PREX1 predicts poor prognosis.PREX1 is closely associated with TGFβsignaling and promotes the metastasis of gastric cancer cells. 展开更多
关键词 Phosphatidylinositol-3 4 5-trisphosphate dependent Rac exchange factor 1 Gastric cancer High expression Poor prognosis METASTASIS transforming growth factorβ1 pathway
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MCIF-Transformer Mask RCNN:Multi-Branch Cross-Scale Interactive Feature Fusion Transformer Model for PET/CT Lung Tumor Instance Segmentation
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作者 Huiling Lu Tao Zhou 《Computers, Materials & Continua》 SCIE EI 2024年第6期4371-4393,共23页
The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided diagnosis.However,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are ... The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided diagnosis.However,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are complex,the edges are blurred,and the sample numbers are unbalanced.To solve these problems,this paper proposes a Multi-branch Cross-scale Interactive Feature fusion Transformer model(MCIF-Transformer Mask RCNN)for PET/CT lung tumor instance segmentation,The main innovative works of this paper are as follows:Firstly,the ResNet-Transformer backbone network is used to extract global feature and local feature in lung images.The pixel dependence relationship is established in local and non-local fields to improve the model perception ability.Secondly,the Cross-scale Interactive Feature Enhancement auxiliary network is designed to provide the shallow features to the deep features,and the cross-scale interactive feature enhancement module(CIFEM)is used to enhance the attention ability of the fine-grained features.Thirdly,the Cross-scale Interactive Feature fusion FPN network(CIF-FPN)is constructed to realize bidirectional interactive fusion between deep features and shallow features,and the low-level features are enhanced in deep semantic features.Finally,4 ablation experiments,3 comparison experiments of detection,3 comparison experiments of segmentation and 6 comparison experiments with two-stage and single-stage instance segmentation networks are done on PET/CT lung medical image datasets.The results showed that APdet,APseg,ARdet and ARseg indexes are improved by 5.5%,5.15%,3.11%and 6.79%compared with Mask RCNN(resnet50).Based on the above research,the precise detection and segmentation of the lesion region are realized in this paper.This method has positive significance for the detection of lung tumors. 展开更多
关键词 PET/CT images instance segmentation mask RCNN interactive fusion transformER
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Backlund transformations, consistent Riccati expansion solvability, and soliton-cnoidal interaction wave solutions of Kadomtsev-Petviashvili equation
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作者 Ping Liu Jie Cheng +1 位作者 Bo Ren Jian-Rong Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期91-99,共9页
The famous Kadomtsev-Petviashvili(KP)equation 1 s a classical equation In soliton tneory.A Backlund transformation between the KP equation and the Schwarzian KP equation is demonstrated by means of the truncated Painl... The famous Kadomtsev-Petviashvili(KP)equation 1 s a classical equation In soliton tneory.A Backlund transformation between the KP equation and the Schwarzian KP equation is demonstrated by means of the truncated Painlev6 expansion in this paper.One-parameter group transformations and one-parameter subgroup-invariant solutions for the extended KP equation are obtained.The consistent Riccati expansion(CRE) solvability of the KP equation is proved.Some interaction structures between soliton-cnoidal waves are obtained by CRE and several evolution graphs and density graphs are plotted. 展开更多
关键词 Kadomtsev-Petviashvili(KP)equation consistent Riccati expansion symmetry Backlund transformation interaction solution
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The Significance of Generalized Gauge Transformation across Fundamental Interactions
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作者 Bi Qiao 《Journal of Modern Physics》 CAS 2023年第5期604-622,共19页
The author of this paper has put forward a unified program of gauge field from the mathematical and physical picture of the principal associated bundles: thinking that our universe may have more fundamental interactio... The author of this paper has put forward a unified program of gauge field from the mathematical and physical picture of the principal associated bundles: thinking that our universe may have more fundamental interactions than the four fundamental interactions, and these basic interaction gauge fields are only the projection components to the base manifold, that is our universe, from a unified gauge potential or connection of the principal associated bundle manifold on the base manifold. These components can satisfy the transformation of gauge potential, and can even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, that is, the generalized gauge Equation (GGE), but the gauge potential or connection on the principal bundle is invariant, corresponding to the invariance of gauge transformation [1]. In this paper, we will continue to discuss this aspect concretely, and specifically construct a spatiotemporal model with the frame bundle as the principal bundle, and the tensor bundle as the associated bundle, so that the four fundamental interactions, especially the electromagnetic interaction and the gravitational interaction, can be reflected in the bottom manifold, that is, the regional distributions in our universe. Furthermore, this paper studies the existence of gauge transformation across basic interactions by establishing a model of gauge transformation of basic interaction field;it is found that the unified expression formula is GGE and the expression relation on the curvature of space-time. Therefore, the author discusses the feasibility of the generalized gauge transformation across the basic electromagnetic interaction and the basic gravitational interaction, and on this basis, specifically determines a method or way to find the generalized gauge transformation, so as to try to realize the last step of the “unification” of the four fundamental interactions in physics, that is, the “unification” of electromagnetism and gravity. 展开更多
关键词 Generalized Gauge transformation Unification of Fundamental interactions Principal Bundle Connection and Curvature
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基于门控循环单元和Transformer的车辆轨迹预测方法 被引量:2
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作者 王庆荣 谭小泽 +1 位作者 朱昌锋 李裕杰 《汽车技术》 CSCD 北大核心 2024年第7期1-8,共8页
为增强自动驾驶车辆对动态环境的理解能力及其道路行驶安全性,提出基于门控循环单元(GRU)和Transformer的车辆轨迹预测模型STGTF,使用GRU提取车辆的历史轨迹特征,通过双层多头注意力(MHA)机制提取车辆的时空交互特征,生成预测轨迹。试... 为增强自动驾驶车辆对动态环境的理解能力及其道路行驶安全性,提出基于门控循环单元(GRU)和Transformer的车辆轨迹预测模型STGTF,使用GRU提取车辆的历史轨迹特征,通过双层多头注意力(MHA)机制提取车辆的时空交互特征,生成预测轨迹。试验结果表明,预测结果的均方根误差(RMSE)平均降低7.3%,STGTF在短期预测和长期预测方面均有不同程度的提升,验证了模型的有效性。 展开更多
关键词 车辆轨迹预测 门控循环单元 transformER 车辆交互 多头注意力机制
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Protein-protein interaction map is a key gateway into liver regeneration 被引量:3
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作者 Chao Xie Run-Zhi Zhu +6 位作者 Yun-Sheng Yuan Hong-Lin He Yan Yu Chao Xie Qiu-Shi Huang Jin Gao Wei Han 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第28期3491-3498,共8页
Recent studies indicate that the process of liver regeneration involves multiple signaling pathways and a variety of genes,cytokines and growth factors. Protein-protein interactions(PPIs)play a role in nearly all even... Recent studies indicate that the process of liver regeneration involves multiple signaling pathways and a variety of genes,cytokines and growth factors. Protein-protein interactions(PPIs)play a role in nearly all events that take place within the cell and PPI maps should be helpful in further understanding the process of liver regeneration.In this review,we discuss recent progress in understanding the PPIs that occur during liver regeneration especially those in the transforming growth factorβsignaling pathways.We believe the use of large-scale PPI maps for integrating the information already known about the liver regeneration is a useful approach in understanding liver regeneration from the standpoint of systems biology. 展开更多
关键词 Liver regeneration Protein-protein interaction Protein-protein interaction maps transforming growth factorβ
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A SEMI-ANALYTICAL AND SEMI-NUMERICAL METHOD FOR SOLVING 2-D SOUND-STRUCTURE INTERACTION PROBLEMS 被引量:8
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作者 Xiang Yu Huang Yuying (College of Civil Engineering and Mechanics,Huazhong University of Science and Technology,Wuhan 430074,China) 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第2期116-126,共11页
Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harm... Based on the transfer matrix method and the virtual source simulation technique, this paper proposes a novel semi-analytical and semi-numerical method for solving 2-D sound- structure interaction problems under a harmonic excitation.Within any integration segment, as long as its length is small enough,along the circumferential curvilinear coordinate,the non- homogeneous matrix differential equation of an elastic ring of complex geometrical shape can be rewritten in terms of the homogeneous one by the method of extended homogeneous capacity proposed in this paper.For the exterior fluid domain,the multi-circular virtual source simulation technique is adopted.The source density distributed on each virtual circular curve may be ex- panded as the Fourier's series.Combining with the inverse fast Fourier transformation,a higher accuracy and efficiency method for solving 2-D exterior Helmholtz's problems is presented in this paper.In the aspect of solution to the coupling equations,the state vectors of elastic ring induced by the given harmonic excitation and generalized forces of coefficients of the Fourier series can be obtained respectively by using a high precision integration scheme combined with the method of extended homogeneous capacity put forward in this paper.According to the superposition princi- ple and compatibility conditions at the interface between the elastic ring and fluid,the algebraic equation of system can be directly constructed by using the least square approximation.Examples of acoustic radiation from two typical fluid-loaded elastic rings under a harmonic concentrated force are presented.Numerical results show that the method proposed is more efficient than the mixed FE-BE method in common use. 展开更多
关键词 sound-structure interaction acoustic radiatlon multi-circular virtual source simulation technique transfer matrix method inverse fast Fourier transformation semi-analytical and semi-numerical method
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融合Transformer和交互注意力网络的方面级情感分类模型
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作者 程艳 胡建生 +5 位作者 赵松华 罗品 邹海锋 詹勇鑫 富雁 刘春雷 《智能系统学报》 CSCD 北大核心 2024年第3期728-737,共10页
现有的大多数研究者使用循环神经网络与注意力机制相结合的方法进行方面级情感分类任务。然而,循环神经网络不能并行计算,并且模型在训练过程中会出现截断的反向传播、梯度消失和梯度爆炸等问题,传统的注意力机制可能会给句子中重要情... 现有的大多数研究者使用循环神经网络与注意力机制相结合的方法进行方面级情感分类任务。然而,循环神经网络不能并行计算,并且模型在训练过程中会出现截断的反向传播、梯度消失和梯度爆炸等问题,传统的注意力机制可能会给句子中重要情感词分配较低的注意力权重。针对上述问题,该文提出了一种融合Transformer和交互注意力网络的方面级情感分类模型。首先利用BERT(bidirectional encoder representation from Transformers)预训练模型来构造词嵌入向量,然后使用Transformer编码器对输入的句子进行并行编码,接着使用上下文动态掩码和上下文动态权重机制来关注与特定方面词有重要语义关系的局部上下文信息。最后在5个英文数据集和4个中文评论数据集上的实验结果表明,该文所提模型在准确率和F1上均表现最优。 展开更多
关键词 方面词 情感分类 循环神经网络 transformER 交互注意力网络 BERT 局部特征 深度学习
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Interaction of elementary waves for relativistic Euler equations 被引量:1
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作者 刘凤玲 盛万成 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期405-409,共5页
In this paper, using the characteristic analysis method, we study the relativistic Euler equations of conservation laws in energy and momentum in special relativity. The interactions of elementary waves for the relati... In this paper, using the characteristic analysis method, we study the relativistic Euler equations of conservation laws in energy and momentum in special relativity. The interactions of elementary waves for the relativistic Euler equations are shown. The collision of two shocks, two centered rarefaction waves, a shock and a rarefaction wave yield corresponding ransmitted waves. The overtaking of two shocks appears a transmitted shock wave, together with a reflected centered rarefaction wave. 展开更多
关键词 interaction of elementary waves relativistic Euler equations strictly hyperbolic Lorenz transformation
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Rational solutions and interaction solutions for(2+1)-dimensional nonlocal Schrodinger equation 被引量:1
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作者 Mi Chen Zhen Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第12期125-134,共10页
A chain of novel higher order rational solutions with some parameters and interaction solutions of a(2+1)-dimensional reverse space–time nonlocal Schrodinger(NLS)equation was derived by a generalized Darboux transfor... A chain of novel higher order rational solutions with some parameters and interaction solutions of a(2+1)-dimensional reverse space–time nonlocal Schrodinger(NLS)equation was derived by a generalized Darboux transformation(DT)which is derived by Taylor expansion and determinants.We obtained a series of higher-order rational solutions by one spectral parameter and we could get the periodic wave solution and three kinds of interaction solutions,singular breather and periodic wave interaction solution,singular breather and traveling wave interaction solution,bimodal breather and periodic wave interaction solution by two spectral parameters.We found a general formula for these solutions in the form of determinants.We also analyzed the complex wave structures of the dynamic behaviors and the effects of special parameters and presented exact solutions for the(2+1)-dimensional reverse space–time nonlocal NLS equation. 展开更多
关键词 Darboux transformation nonlocal Schrodinger equation rational solutions interaction solutions
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Principle of Interaction between Plastic Volumetric and Shear Strains and the Constitutive Model for Geotechnical Materials 被引量:2
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作者 Wang Jingtao(1.Department of Architectural Engineering, Xinyang Normal University, Xinyang 464000, Henan, China 2.School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan 430074, China) 《工程科学(英文版)》 2007年第2期129-138,共10页
Here is proposed the principle of interaction between plastic volumetric and shear strains, revealing the main origin of generating the complexity and variety of deformations for geotechnical materials. Here are also ... Here is proposed the principle of interaction between plastic volumetric and shear strains, revealing the main origin of generating the complexity and variety of deformations for geotechnical materials. Here are also explained the manners of the interaction between plastic volumetric and shear strains and the conditions of generating shear dilatancy. It is demonstrated that dependency of the stress path exists and is a combination of effects of this interaction. According to this principle, it is theoretically proved that the space critical state line exists, and is unique and independent of the stress history. Based on this principle, the constitutive models that are able completely and accurately to characterize the basic behavior features for geotechnical materials have been constructed within the framework of thermodynamics. What is determined is a general expression of the constitutive relation as well as the inequality of the dissipative potential increment for obeying the second law of thermodynamics. 展开更多
关键词 interaction BETWEEN VOLUMETRIC and SHEAR strains constitutive model for rock and soil dependency of stress path pressure-sensitivity SHEAR DILATANCY
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ON THE EXPECTED DISCOUNTED PENALTY FUNCTION IN A MARKOV-DEPENDENT RISK MODEL WITH CONSTANT DIVIDEND BARRIER 被引量:7
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作者 刘娟 徐建成 胡亦钧 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1481-1491,共11页
This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with gi... This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with given initial environment state, is derived and solved. Explicit formulas for the discounted penalty function are obtained when the initial surplus is zero or when all the claim amount distributions are from rational family. In two state model, numerical illustrations with exponential claim amounts are given. 展开更多
关键词 Markov-dependent risk model dividend barrier Cerber-Shiu function integro-differential equation Laplace transform
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融合多种时空自注意力机制的Transformer交通流预测模型 被引量:1
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作者 曹威 王兴 +2 位作者 邹复民 金彪 王小军 《计算机系统应用》 2024年第4期82-92,共11页
交通流预测是智能交通系统中实现城市交通优化的一种重要方法,准确的交通流量预测对交通管理和诱导具有重要意义.然而,因交通流本身存在高度时空依赖性而表现出复杂的非线性特征,现有的方法主要考虑路网中节点的局部时空特征,忽略了路... 交通流预测是智能交通系统中实现城市交通优化的一种重要方法,准确的交通流量预测对交通管理和诱导具有重要意义.然而,因交通流本身存在高度时空依赖性而表现出复杂的非线性特征,现有的方法主要考虑路网中节点的局部时空特征,忽略了路网中所有节点的长期时空特征.为了充分挖掘交通流数据复杂的时空依赖,提出一种融合多种时空自注意力机制的Transformer交通流预测模型(MSTTF).该模型在嵌入层通过位置编码嵌入时间和空间信息,并在注意力机制层融合邻接空间自注意力机制,相似空间自注意力机制,时间自注意力机制,时间-空间自注意力机制等多种自注意力机制挖掘数据中潜在的时空依赖关系,最后在输出层进行预测.结果表明,MSTTF模型与传统时空Transformer相比,MAE平均降低了10.36%.特别地,相比于目前最先进的PDFormer模型,MAE平均降低了1.24%,能取得更好的预测效果. 展开更多
关键词 交通流预测 智能交通 时空依赖性 transformER 自注意力机制
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Stress Dependence of Transformation Plastic Behavior 被引量:2
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作者 Tatsuo Inoue 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期208-213,共6页
Transformation plasticity is known to play an important role in the course of heat treatment processes, and so affect the results of heat treatment simulations, which means that the transformation plasticity coefficie... Transformation plasticity is known to play an important role in the course of heat treatment processes, and so affect the results of heat treatment simulations, which means that the transformation plasticity coefficient is necessary to be identifies. The authors developed a new method by use of four-point bending system of a beam to identify transformation plasticity coefficient taking advantage of its easiness and high accuracy compared with other conventional methods like tension test, etc., and identified the coefficient for four kinds of steels; plane carbon steel, Cr-steel, Cr-Mo steel and bearing steel. In this paper, further experimental data are presented for the steels if the coefficient Kp during pearlite transformation depend on the applied stress. Obtained results reveals that the stress dependence of Kp is rather trivial except for uncertain tendency detected in plane carbon steel. The relation between the Kp and carbon content included is discussed in comparison with other data referred from references. 展开更多
关键词 相变塑性 四点弯曲试验 应力关系 金属热机械性能
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Numerical Simulation of ATPS Parachute Transient Dynamics Using Fluid-Structure Interaction Method
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作者 Fan Yuxin Xia Jian 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第5期535-542,共8页
In order to simulate and analyze the dynamic characteristics of the parachute from advanced tactical parachute system(ATPS),a nonlinear finite element algorithm and a preconditioning finite volume method are employed ... In order to simulate and analyze the dynamic characteristics of the parachute from advanced tactical parachute system(ATPS),a nonlinear finite element algorithm and a preconditioning finite volume method are employed and developed to construct three dimensional parachute fluid-structure interaction(FSI)model.Parachute fabric material is represented by membrane-cable elements,and geometrical nonlinear algorithm is employed with wrinkling technique embedded to simulate the large deformations of parachute structure by applying the NewtonRaphson iteration method.On the other hand,the time-dependent flow surrounding parachute canopy is simulated using preconditioned lower-upper symmetric Gauss-Seidel(LU-SGS)method.The pseudo solid dynamic mesh algorithm is employed to update the flow-field mesh based on the complex and arbitrary motion of parachute canopy.Due to the large amount of computation during the FSI simulation,massage passing interface(MPI)parallel computation technique is used for all those three modules to improve the performance of the FSI code.The FSI method is tested to simulate one kind of ATPS parachutes to predict the parachute configuration and anticipate the parachute descent speeds.The comparison of results between the proposed method and those in literatures demonstrates the method to be a useful tool for parachute designers. 展开更多
关键词 parachute dynamics fluid-structure interaction nonlinear structure dynamics time dependent flow parallel computation technique
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