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Refinement of Adaptive Dynamical Simulation of Quantum Mechanical Double Slit Interference Phenomenon
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作者 Tadashi Ando Andrei Khrennikov Ichiro Yamato 《Journal of Modern Physics》 2024年第3期239-249,共11页
We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. S... We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. Several properties such as concave single slit pattern and large influence of slight displacement of the emission position were different from the experimental results. In this study we tried other slit conditions and obtained consistent patterns with experiments. We do not claim that the adaptive dynamics is the principle of quantum mechanics, but the present results support the probability of adaptive dynamics as the candidate of the basis of quantum mechanics. We discuss the advantages of the adaptive dynamical view for foundations of quantum mechanics. 展开更多
关键词 double Slit Interference Adaptive dynamics Quantum Mechanics Particle model Simulation
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A hybrid Lagrangian-Eulerian numerical model for sea-ice dynamics 被引量:3
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作者 JI Shunying LI Hai +2 位作者 SHEN Hung Tao WANG Ruixue YUE Qianjin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第5期12-24,共13页
A hybrid Lagrangian - Eulerian (HLE) method is developed for sea ice dynamics, which combines the high computational efficiency of finite difference method (FDM) with the high numerical accuracy of smoothed partic... A hybrid Lagrangian - Eulerian (HLE) method is developed for sea ice dynamics, which combines the high computational efficiency of finite difference method (FDM) with the high numerical accuracy of smoothed particle hydrodynamics (SPH). In this HLE model, the sea ice cover is represented by a group of Lagrangian ice particles with their own thicknesses and concentrations. These ice variables are interpolated to the Eularian gird nodes using the Gaussian interpolation function. The FDM is used to determine the ice velocities at Eulerian grid nodes, and the velocities of Lagrangian ice particles are interpolated from these grid velocities with the Gaussian function also. The thicknesses and concentrations of ice particles are determined based on their new locations. With the HLE numerical model, the ice ridging process in a rectangular basin is simulated, and the simulated results are validated with the analytical solution. This method is also applied to the simulation of sea ice dynamics in a vortex wind field. At last, this HLE model is applied to the Bohai Sea, and the simulated concentration, thickness and velocity match the satellite images and the field observed data well. 展开更多
关键词 hybrid Lagrangian - Eulerian model sea-ice dynamics numerical model
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Roll System and Stock's Multi-parameter Coupling Dynamic Modeling Based on the Shape Control of Steel Strip 被引量:3
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作者 Yang ZHANG Yan PENG +1 位作者 Jianliang SUN Yong ZANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期614-624,共11页
The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformatio... The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformation, it is necessary to consider the transverse periodic movement of stock in the rolling deformation area which is caused by the flexural deformation movement of roll system simul- taneously. Therefore, the displacement field of roll system and flow of metal in the deformation area is described by kinematic analysis in the dynamic system. Through intro- ducing the lateral displacement function of metal in the deformation area, the dynamic variation of per unit width rolling force can be determined at the same time. Then the coupling law caused by the co-effect of rigid movement and flexural deformation of the system structural elements is determined. Furthermore, a multi-parameter coupling dynamic model of the roll system and stock is established by the principle of virtual work. More explicitly, the cou- pled motion modal analysis was made for the roll system. Meanwhile, the analytical solutions for the flexural defor- mation movement's mode shape functions of rolls are discussed. In addition, the dynamic characteristic of the lateral flow of metal in the rolling deformation area has been analyzed at the same time. The establishment ofdynamic lateral displacement function of metal in the deformation area makes the foundation for analyzing the coupling law between roll system and rolling deformation area, and provides a theoretical basis for the realization of the dynamic shape control of steel strip. 展开更多
关键词 Roll system Rolling deformation area Coupling dynamic model Mode shape function - Lateraldisplacement function
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An Application of the Adjoint Method to a Statistical-Dynamical Tropical-Cyclone Prediction Model (SD-90)Ⅱ:Real Tropical Cyclone Cases 被引量:1
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作者 项杰 廖前锋 +3 位作者 黄思训 兰伟仁 冯强 周凤才 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第1期118-126,共9页
In the first paper in this series, a variational data assimilation of ideal tropical cyclone (TC) tracks was performed for the statistical-dynamical prediction model SD-90 by the adjoint method, and a prediction of ... In the first paper in this series, a variational data assimilation of ideal tropical cyclone (TC) tracks was performed for the statistical-dynamical prediction model SD-90 by the adjoint method, and a prediction of TC tracks was made with good accuracy for tracks containing no sharp turns. In the present paper, the cases of real TC tracks are studied. Due to the complexity of TC motion, attention is paid to the diagnostic research of TC motion. First, five TC tracks are studied. Using the data of each entire TC track, by the adjoint method, five TC tracks are fitted well, and the forces acting on the TCs are retrieved. For a given TC, the distribution of the resultant of the retrieved force and Coriolis force well matches the corresponding TC track, i.e., when a TC turns, the resultant of the retrieved force and Coriolis force acts as a centripetal force, which means that the TC indeed moves like a particle; in particular, for TC 9911, the clockwise looping motion is also fitted well. And the distribution of the resultant appears to be periodic in some cases. Then, the present method is carried out for a portion of the track data for TC 9804, which indicates that when the amount of data for a TC track is sufficient, the algorithm is stable. And finally, the same algorithm is implemented for TCs with a double-eyewall structure, namely Bilis (2000) and Winnie (1997), and the results prove the applicability of the algorithm to TCs with complicated mesoscale structures if the TC track data are obtained every three hours. 展开更多
关键词 adjoint method TC double eyewalls statistical-dynamical prediction model
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Dynamics modeling and simulation of a saucer-shaped stratospheric aerostat with an under-slung nacelle
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作者 ZHAO Ming XIAO Chang +1 位作者 ZHOU Ping-fang DUAN Deng-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1288-1298,共11页
A new concept stratospheric aerostat is investigated which consists of a saucer-shaped hull, multi-vectored thrusters, and an under-slung nacelle. The design of this aerostat involves tradeoffs between conventional ai... A new concept stratospheric aerostat is investigated which consists of a saucer-shaped hull, multi-vectored thrusters, and an under-slung nacelle. The design of this aerostat involves tradeoffs between conventional airship and high altitude balloon. The sling connection simplifies structure design significantly, but brings challenges for dynamics analysis. Dynamics modeling for this aerostat is a kind of double-body problem with geometric constraint. Nonlinear dynamics model is established by considering the effects of under-slung nacelle. Oscillation behavior of this double-body system is superposed by a long-period oscillation of the hull and a short-period oscillation of the nacelle. The length of sling only influences the short-period oscillation but the mass ratio of nacelle to main body determines the stability of system. Finally, an envelope about mass ratio and maximal open loop forward thrust as well as speed is presented, where the system is stable. 展开更多
关键词 saucer-shaped AEROSTAT double-body under-slung dynamicS modeling
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Unsteady aerodynamics modeling for flight dynamics application 被引量:13
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作者 Qing Wang Kai-Feng He. +3 位作者 Wei-Qi Qian Tian-Jiao Zhang Yan-Qing Cheng Kai-Yuan Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期14-23,共10页
In view of engineering application, it is practicable to decompose the aerodynamics into three components: the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due... In view of engineering application, it is practicable to decompose the aerodynamics into three components: the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function (RBF) network. For an aircraft configuration, the mathematical models of 6- component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynam- ics, respectively. The results show that: (1) unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; (2) unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and (3) unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability 展开更多
关键词 Unsteady aerodynamics High angle of attack Mathematical model Flight dynamics - Bifurcation analysis Post-stall maneuver
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Promoting surface reconstruction of NiFe layered double hydroxides via intercalating[Cr(C_(2)O_(4))_(3)]^(3-)for enhanced oxygen evolution 被引量:2
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作者 Yujie Wu Minglei Song +8 位作者 Yu-Cheng Huang Chung-Li Dong Yingying Li Yuxuan Lu Bo Zhou Dongdong Wang Jianfeng Jia Shuangyin Wang Yanyong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期140-148,I0005,共10页
Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(... Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis. 展开更多
关键词 NiFe layered double hydroxides [Cr(C_(2)O_(4))_(3)]^(3-)intercalation dynamic restructuring Operando spectroscopies Oxygen evolution reaction
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Evaluation on Spot Weld Models in Structural Dynamic Analysis of Automotive Body in White 被引量:9
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作者 LIANG Jianyong LIANG Jun FANG Guodong PAN Zimin LI Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期84-90,共7页
Spot weld models are widely used in finite element analysis(FEA) of automotive body in white(BIW) to predict static,dynamic,durability and other characteristics of automotive BIW.However,few researches are done on... Spot weld models are widely used in finite element analysis(FEA) of automotive body in white(BIW) to predict static,dynamic,durability and other characteristics of automotive BIW.However,few researches are done on evaluation of the validity of these spot weld models in structural dynamic analysis of BIW.To evaluate the validity and accuracy of spot weld models in structural dynamic analysis of BIW,two object functions,error function and deviation function,are introduced innovatively.Modal analysis of Two-panel and Double-hat structures,which are the dominated structures in BIW,is conducted,and the values of these two object functions are obtained.Based on the values of object functions,the validity of these spot weld models are evaluated.It is found that the area contact method(ACM2) and weld element connection(CWELD) can give more precise prediction in modal analysis of these two classical structures,thus are more applicable to structural dynamic analysis of automotive BIW.Modal analysis of a classical BIW is performed,which further confirms this evaluation.The error function and deviation function proposed in this research can give guidance on the adaptability of spot weld models in structural dynamic analysis of BIW.And this evaluation method can also be adopted in evaluation of other finite element models in static,dynamic and other kinds of analysis for automotive structures. 展开更多
关键词 spot weld model structural dynamic analysis modal analysis two-panel structure double-hat structure body in white
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Dynamic constitutive model for soils considering asymmetry of skeleton curve
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作者 Guoxing Chen Hua Pan +1 位作者 Hui Long Xiaojun Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第5期400-405,共6页
Based on the asymmetric characteristic of skeleton curve obtained from dynamic tests on soils,a function with double asymptotes is proposed for describing the dynamic constitutive relations of soils.The hysteresis loo... Based on the asymmetric characteristic of skeleton curve obtained from dynamic tests on soils,a function with double asymptotes is proposed for describing the dynamic constitutive relations of soils.The hysteresis loops observed during unloading and reloading show the same form as the skeleton curve and are constructed by taking the ultimate stress as the corresponding asymptote.The coeffcient of initial unloading modulus is used to ensure that the constructed hysteresis loop fts well with the experimental data.Then,a new dynamic constitutive model considering the asymmetry of skeleton curve is elaborated.The verifcation tests on saturated Nanjing fne sand are performed using a hollow cylinder apparatus to verify the applicability of the UD model.It is found that the predicted curves by the UD model agree well with the test data. 展开更多
关键词 Function with double asymptotes dynamic constitutive model Shear modulus Damping ratio Complex initial stress state
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Bus frequency optimization in a large-scale multi-modal transportation system:integrating 3D-MFD and dynamic traffic assignment
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作者 Kai Yuan Dandan Cui Jiancheng Long 《Digital Transportation and Safety》 2023年第4期241-252,共12页
A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result... A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result in more serious congestion.On the other hand,a low-frequency bus service would increase the waiting time for passengers and would not reduce the use of private cars.It is important to strike a balance between high and low frequencies in order to minimize the total delays for all road users.It is critical to formulate the impacts of bus frequency on congestion dynamics and mode choices.However,as far as the authors know,most proposed bus frequency optimization formulations are based on static demand and the Bureau of Public Roads function,and do not properly consider the congestion dynamics and their impacts on mode choices.To fill this gap,this paper proposes a bi-level optimization model.A three-dimensional Macroscopic Fundamental Diagram based modeling approach is developed to capture the bi-modal congestion dynamics.A variational inequality model for the user equilibrium in mode choices is presented and solved using a double projection algorithm.A surrogate model-based algorithm is used to solve the bi-level programming problem. 展开更多
关键词 Three-dimensional macroscopic fundamental diagram dynamic traffic assignment Bi-level programming model double projection algorithm Surrogate model-based algorithm
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Assessing dynamic modulus properties for typical asphalt mixtures in Jiangsu
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作者 王昊鹏 杨军 +1 位作者 周文章 陈先华 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期99-105,共7页
To investigate the validity of two dynamic modulus predictive models( Witczak 1-37 A viscosity-based model and Witczak 1-40 D shear modulus-based model) in the context of Jiangsu, and evaluate the effect of differen... To investigate the validity of two dynamic modulus predictive models( Witczak 1-37 A viscosity-based model and Witczak 1-40 D shear modulus-based model) in the context of Jiangsu, and evaluate the effect of different mixture design variables( aggregate gradations, binder type, and volumetric properties) on dynamic modulus E*, asphalt mixtures commonly used in the local surface layer, including Sup-13 and AC-13, are prepared in the laboratory and their dynamic modulus E*values are predicted based on the above mentioned models. The corresponding asphalt tests, including viscosity and dynamic shear modulus tests, are also carried out to obtain the prediction model parameters. The test results showthat binder type and asphalt content have a significant impact on dynamic modulus.There is a good correlation between the E*values based on above two predictive models and the measured E*, while a relatively lower bias can be expected from Witczak 1-37 A model. The test results can be used for the calibration of dynamic modulus with higher accuracy. 展开更多
关键词 dynamic modulus prediction models asphalt pavement Witczak 1-37A Witczak 1-40D mechanistic empirical pavement design guide
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Lateral dynamic flight stability of hovering insects: theory vs. numerical simulation 被引量:4
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作者 Yan-Lai Zhang Jiang-Hao Wu Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期221-231,共11页
In the present paper, the lateral dynamic flight stability properties of two hovering model insects are predicted by an approximate theory based on the averaged model, and computed by numerical simulation that solves ... In the present paper, the lateral dynamic flight stability properties of two hovering model insects are predicted by an approximate theory based on the averaged model, and computed by numerical simulation that solves the complete equations of motion coupled with the Naviertokes equations. Comparison between the theoretical and simulational results provides a test to the validity of the assumptions made in the theory. One of the insects is a model dronefly which has relatively high wingbeat frequency (164Hz) and the other is a model hawkmoth which has relatively low wingbeat frequency (26 Hz). The following conclusion has been drawn. The theory based on the averaged model works well for the lateral motion of the dronefly. For the hawkmoth, relatively large quantitative differences exist between theory and simulation. This is because the lateral non-dimensional eigenvalues of the hawkmoth are not very small compared with the non-dimensional flapping frequency (the largest lateral non-dimensional eigenvalue is only about 10% smaller than the non-dimensional flapping frequency). Nevertheless, the theory can still correctly predict variational trends of the dynamic properties of the hawkmoth's lateral motion. 展开更多
关键词 Insect - Hovering Lateral dynamic flight stabil- ity Averaged model Equations-of-motion Navier-Stokes simulation
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Dynamics and control of variable geometry truss manipulator 被引量:1
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作者 Xiaofeng LIU Qishuai WANG +1 位作者 Haiquan LI Guoping CAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第2期243-262,共20页
Variable geometry truss manipulator (VGTM) has potential to work in the future space applications, of which a dynamic model is important to dynamic analysis and control of the system. In this paper, an approach is p... Variable geometry truss manipulator (VGTM) has potential to work in the future space applications, of which a dynamic model is important to dynamic analysis and control of the system. In this paper, an approach is presented to model the dynamic equations of a VGTM by independent variables, which consists of two double-octahedral truss units and a 3-revolute-prismatic-spherical (3-RPS) parallel manipulator. In this ap- proach, the kinematic recursive relations of two adjacent bodies and geometric constrains are used to deduce the kinematic equations of the VGTM, and Jourdain's velocity varia- tion principle is adopted to establish the dynamic equations of the system. The validity of the proposed dynamic model is verified by comparison of numerical simulations with the software ADAMS. Besides, an active controller for trajectory tracking of the system is designed by the computed torque method. The effectiveness of the controller is numer- ically proved. 展开更多
关键词 variable geometry truss manipulator (VGTM) double-octahedral truss unit 3-revolute-prismatic-spherical (3-RPS) parallel manipulator dynamic modeling activecontrol
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基于多尺度有限元建模技术的GJ-III型扣件轨道动力特性分析
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作者 冷圣禧 李伟 +3 位作者 姚学东 周志军 温泽峰 任愈 《振动与冲击》 EI CSCD 北大核心 2024年第23期75-85,共11页
GJ-III型扣件轨道作为地铁线路一种中等减振轨道,服役后出现钢轨短波长波磨,导致高频轮轨振动噪声问题。为探明该轨道的动力特性,利用ABAQUS软件建立减振扣件轨道的三维有限元模型。为减小有限长轨道边界反射波影响并同时保证计算效率,... GJ-III型扣件轨道作为地铁线路一种中等减振轨道,服役后出现钢轨短波长波磨,导致高频轮轨振动噪声问题。为探明该轨道的动力特性,利用ABAQUS软件建立减振扣件轨道的三维有限元模型。为减小有限长轨道边界反射波影响并同时保证计算效率,采用多尺度建模技术将轨道简化为梁-壳-实体模型。利用该模型探究了轮轨耦合作用下的轨道垂向动力特性,分析了扣件垂向刚度和阻尼对轨道垂向频响特性的影响。结果表明:(1)将50.0 m实体轨道模型简化为12.5 m实体和37.5 m梁-壳模型,可节约65.3%的计算时间,同时仿真与现场测试结果基本一致。(2)钢轨垂向一阶弯曲和pinned-pinned共振模态在轨道垂向位移导纳上表征明显,其频带分别为100~150 Hz和1022~1101 Hz。(3)减振扣件轨道在100 Hz以下振动响应表现为钢轨和道床板的整体弯曲和扭转振动;车辆静载集中力引起的钢轨预应力会诱发400~800 Hz轮对间轨道垂向频响峰值。(4)考虑柔性轮对作用后,轨道垂向位移导纳在分别在43 Hz、381 Hz和641 Hz处出现新的明显峰值,分别对应于轮轨耦合的P2共振模态、轮对间钢轨垂向二、三阶弯曲模态。柔性车轮在180 Hz、341 Hz和504 Hz处的振动模态也会引起钢轨垂向导纳出现新峰值。轮对质量效应对减振扣件轨道50~250 Hz内垂向振动有抑制作用,钢轨不易萌生该频段波磨。(5)钢轨垂向一阶弯曲、P2共振和轮对间钢轨垂向弯曲频率均随扣件垂向刚度增加而增加,扣件垂向阻尼仅对轨道导纳波动幅值有抑制作用。 展开更多
关键词 地铁 双层非线性减振扣件 多尺度有限元建模 轨道动态特征 轮轨耦合
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Chiral σ-ω Model Study of Hot Dense Nuclear Matter
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作者 Liu, Lianggang 《Chinese journal of nuclear physics》 EI 1995年第1期5-12,共8页
The hot dense nuclear matter is studied in the chiral σ-ω model in theformalism of thermo-field dynamics.The binding energy,pressure and effective mass ofnucleon are calculated in the level of one-loop vaccum quantu... The hot dense nuclear matter is studied in the chiral σ-ω model in theformalism of thermo-field dynamics.The binding energy,pressure and effective mass ofnucleon are calculated in the level of one-loop vaccum quantum fluctuation.The tem-perature effect is found very large at high temperature and the pressure can not reachsaturation as a function of nuclear density. 展开更多
关键词 CHIRAL σ-ω model Thermo-field dynamics HOT DENSE NUCLEAR MATTER Eqtiation of state
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Fixed-Bed Column Adsorption Modeling of MnO4- Ions from Acidic Aqueous Solutions on Activated Carbons Prepared with the Biomass
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作者 Charly Mve Mfoumou Francis Ngoye +3 位作者 Pradel Tonda-Mikiela Mbouiti Lionel Berthy Bouassa Mougnala Spenseur Guy Raymond Feuya Tchouya 《Open Journal of Inorganic Chemistry》 CAS 2023年第2期25-42,共18页
Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-<... Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-</sup> ions in acidic media on fixed bed column and on the kinetic modeling of experimental data of breakthrough curves of  MnO<sub>4</sub>-</sup> ions obtained. Results on the adsorption of MnO<sub>4</sub>-</sup>  ions in fixed-bed dynamics obtained on AC-400 and AC-600 adsorbents beds indicated that the AC-400 bed appears to be the most efficient in removing MnO<sub>4</sub>-</sup>  ions in acidic media. Indeed, the adsorbed amounts, the adsorbed capacities at saturation and the elimination percentage of MnO<sub>4</sub>-</sup>  ions obtained with AC-400 (31.24 mg;52.06 mg·g<sup>-1</sup> and 41.65% respectively) were higher compared to those obtained with AC-600 (9.87 mg;16.45 mg·g<sup>-1</sup> and 17.79% respectively). The breakthrough curves kinetic modeling revealed that the Thomas model and the pseudo-first-order kinetic model were the most suitable models to describe the adsorption of MnO<sub>4</sub>-</sup>  ions on adsorbents studied in our experimental conditions. The results of the intraparticle diffusion model showed that intraparticle diffusion was involved in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions on investigated adsorbents and was not the limiting step and the only process controlling MnO<sub>4</sub>-</sup>  ions adsorption. In contrast to AC-400, the intraparticle diffusion on AC-600 bed plays an important role in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions. 展开更多
关键词 Acidic Media MnO4 style=margin-left:-6px >- BIOMASS Activated Carbon dynamic Adsorption Kinetics models
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Lateral Dynamic Analysis and Motion Control of a Jet Trencher in Ocean Currents
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作者 Xiang Li Tao Wang +1 位作者 Min Zhao Tong Ge 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期26-31,共6页
In order to control the lateral motion of a jet trencher which is important for stable trenching operation,the oscillation characteristics of the jet trencher are researched. The jet trencher is simplified into a sing... In order to control the lateral motion of a jet trencher which is important for stable trenching operation,the oscillation characteristics of the jet trencher are researched. The jet trencher is simplified into a single degree of freedom model with restoring and damping force. The nonlinear mathematical model of the trencher laterally oscillating in ocean currents is established,and its approximate analytical solution is obtained.Results show that the analytical solution has small differences with numerical solution based on the fourth-order Runge-Kutta method and can effectively describe the underwater oscillation. A double-loop PID controller is designed to control the lateral motion displacement of the trencher to return to the center of the pipeline route which is effective and robust for the propulsion system. 展开更多
关键词 TRENCHER dynamic model analytical solution double-loop control ocean currents
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A theoretical study of the signal enhancement mechanism of coaxial DP-LIBS
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作者 宋震 王俊霄 +11 位作者 王钢 张雷 王树青 张婉飞 马晓飞 刘珍荣 罗学彬 马维光 叶泽甫 朱竹君 尹王保 贾锁堂 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期156-164,共9页
In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectra... In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectral signal enhancement is paramount.To aid researchers in identification of optimal signal enhancement conditions and more accurate interpretation of the underlying signal enhancement mechanisms,theoretical simulations of the spatiotemporal processes of coaxial DP-LIBS-induced plasma have been established in this work.Using a model based on laser ablation and two-dimensional axisymmetric fluid dynamics,plasma evolutions during aluminum–magnesium alloy laser ablation under single-pulse and coaxial dualpulse excitations have been simulated.The influences of factors,such as delay time,laser fluence,plasma temperature,and particle number density,on the DP-LIBS spectral signals are investigated.Under pulse intervals ranging from 50 to 1500 ns,the time evolutions of spectral line intensity,dual-pulse emission enhancement relative to the single-pulse results,laser irradiance,spatial distribution of plasma temperature and species number density,as well as laser irradiance shielded by plasma have been obtained.The study indicates that the main reason behind the radiation signal enhancement in coaxial DP-LIBS-induced plasma is attributed to the increased species number density and plasma temperature caused by the second laser,and it is inferred that the shielding effect of the plasma mainly occurs in the boundary layer of the stagnation point flow over the target surface.This research provides a theoretical basis for experimental research,parameter optimization,and signal enhancement tracing in DP-LIBS. 展开更多
关键词 laser-induced plasma radiation fluid dynamics model double pulse laser-induced breakdown spectroscopy(DP-LIBS) laser ablation signal enhancement mechanism
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6061-T6铝合金薄板双脉冲MIG焊动态组合热源模型 被引量:1
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作者 陈鑫 杨立飞 +2 位作者 王佳宁 张冠宸 司徒德蓉 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2022年第12期83-91,共9页
为准确得出铝合金薄板双脉冲熔化极惰性气体保护焊(双脉冲MIG焊)焊接温度场分布特征,提出一种基于铝合金薄板全熔透焊接热量分布及焊缝成形特点的动态组合热源模型,通过编写子程序,对有限元软件进行二次开发,实现动态组合热源模型在空... 为准确得出铝合金薄板双脉冲熔化极惰性气体保护焊(双脉冲MIG焊)焊接温度场分布特征,提出一种基于铝合金薄板全熔透焊接热量分布及焊缝成形特点的动态组合热源模型,通过编写子程序,对有限元软件进行二次开发,实现动态组合热源模型在空间上的分布加载,得出仿真过程焊缝形貌及温度场分布特征.对2 mm厚6061-T6铝合金薄板进行双脉冲MIG焊对接焊接实验,得出焊缝形貌特征并记录测温点温度数据,绘制测温点的热循环曲线.对比仿真与实验结果发现,对于铝合金薄板全熔透焊接,利用动态组合热源模型得出的焊缝形貌与实际焊缝形貌拟合较好,温度场仿真误差在允许范围内,最大误差点出现在距焊缝20 mm处,最大误差为12.25%. 展开更多
关键词 双脉冲MIG焊 铝合金 温度场 动态组合热源模型 熔滴过渡
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系统动力学视角下国企人力资源管理策略-以D民航国企安检部门为例 被引量:5
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作者 段哲哲 黄昊 汪澜 《西安财经学院学报》 CSSCI 2018年第1期54-62,共9页
以D民航国企安检部门为个案研究,试图揭开现有民航国企在国资管理部门"双控"监管体系下,受到民航总局人员配置以及安全标准,劳动部门工时、薪酬以及用工方式标准法规条款等多重外部约束情形下,民航国企内部人力资源管理运作... 以D民航国企安检部门为个案研究,试图揭开现有民航国企在国资管理部门"双控"监管体系下,受到民航总局人员配置以及安全标准,劳动部门工时、薪酬以及用工方式标准法规条款等多重外部约束情形下,民航国企内部人力资源管理运作黑箱及所面临困境。通过访谈与历史数据的分析,构建系统动力学模型来模拟四种政策下的长期运行结果,找到两个高杠杆解:内部需要利用技术与管理手段优化排班,提高作业效率;外部需要国资管理部门改变薪酬总额管控方式,提升D企业薪酬竞争力。 展开更多
关键词 系统动力学 “双控”模式 国企 人力资源管理
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