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Hubble Tension Explanation from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期106-125,共20页
In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of t... In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of the evolution of space-time as well as an equation of state that retains all the infinitesimal terms. We find an explanation of the Hubble tension H<sub>0</sub>. Indeed, we have seen that this constant depends on the transceiver pair which can vary from the lowest observable value, from photons of the CMB (theoretical [km/s/Mpc]) to increasingly higher values depending on the earlier origin of the formation of the observed galaxy or cluster (ETG ~0.3 [Gy], ~74 [km/s/Mpc]). We have produced a theoretical table of the values of the constant according to the possible pairs of transmitter/receiver in the case where these galaxies follow the Hubble flow without large disturbance. The calculated theoretical values of the constant are in the order of magnitude of all values mentioned in past studies. Subsequently, we applied the models to 9 galaxies and COMA cluster and found that the models predict acceptable values of their distances and Hubble constant since these galaxies mainly follow the Hubble flow rather than the effects of a galaxy cluster or a group of clusters. In conclusion, we affirm that this Hubble tension does not really exist and it is rather the understanding of the meaning of this constant that is questioned. 展开更多
关键词 model of the Universe Cosmological Constant Hubble Constant Hubble’s tension Hubble-Lemaître Law Hubble’s Flow
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Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review 被引量:1
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作者 Bo Han Weishi Liang +4 位作者 Yong Hai Duan Sun Hongtao Ding Yihan Yang Peng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期563-570,共8页
Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the i... Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and behavior.Very few studies have been published on the specific characteristics of distraction spinal cord injury.In this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this disease.In addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord injury.We provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease. 展开更多
关键词 animal models behavior DISTRACTION heterogeneity HISTOLOGY mechanism NEUROPHYSIOLOGY spinal cord injury systematic review tension
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Static-to-kinematic modeling and experimental validation of tendon-driven quasi continuum manipulators with nonconstant subsegment stiffness
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作者 郑先杰 丁萌 +2 位作者 刘辽雪 王璐 郭毓 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期316-326,共11页
Continuum robots with high flexibility and compliance have the capability to operate in confined and cluttered environments. To enhance the load capacity while maintaining robot dexterity, we propose a novel non-const... Continuum robots with high flexibility and compliance have the capability to operate in confined and cluttered environments. To enhance the load capacity while maintaining robot dexterity, we propose a novel non-constant subsegment stiffness structure for tendon-driven quasi continuum robots(TDQCRs) comprising rigid-flexible coupling subsegments.Aiming at real-time control applications, we present a novel static-to-kinematic modeling approach to gain a comprehensive understanding of the TDQCR model. The analytical subsegment-based kinematics for the multisection manipulator is derived based on screw theory and product of exponentials formula, and the static model considering gravity loading,actuation loading, and robot constitutive laws is established. Additionally, the effect of tension attenuation caused by routing channel friction is considered in the robot statics, resulting in improved model accuracy. The root-mean-square error between the outputs of the static model and the experimental system is less than 1.63% of the arm length(0.5 m). By employing the proposed static model, a mapping of bending angles between the configuration space and the subsegment space is established. Furthermore, motion control experiments are conducted on our TDQCR system, and the results demonstrate the effectiveness of the static-to-kinematic model. 展开更多
关键词 static-to-kinematic modeling scheme tendon-driven quasi continuum robot nonconstant subsegment stiffness tension attenuation effect
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JWST Discoveries and the Hypersphere World-Universe Model: Transformative New Cosmology
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1806-1834,共29页
Twenty-six years ago, a small committee report built upon earlier studies to articulate a compelling and poetic vision for the future of astronomy. This vision called for an infrared-optimized space telescope with an ... Twenty-six years ago, a small committee report built upon earlier studies to articulate a compelling and poetic vision for the future of astronomy. This vision called for an infrared-optimized space telescope with an aperture of at least four meters. With the support of their governments in the US, Europe, and Canada, 20,000 people brought this vision to life as the 6.5-meter James Webb Space Telescope (JWST). The telescope is working perfectly, delivering much better image quality than expected [1]. JWST is one hundred times more powerful than the Hubble Space Telescope and has already captured spectacular images of the distant universe. A view of a tiny part of the sky reveals many well-formed spiral galaxies, some over thirteen billion light-years away. These observations challenge the standard Big Bang Model (BBM), which posits that early galaxies should be small and lack well-formed spiral structures. JWST’s findings are prompting scientists to reconsider the BBM in its current form. Throughout the history of science, technological advancements have led to new results that challenge established theories, sometimes necessitating their modification or even abandonment. This happened with the geocentric model four centuries ago, and the BBM may face a similar reevaluation as JWST provides more images of the distant universe. In 1937, P. Dirac proposed the Large Number Hypothesis and the Hypothesis of Variable Gravitational Constant, later incorporating the concept of Continuous Creation of Matter in the universe. The Hypersphere World-Universe Model (WUM) builds on these ideas, introducing a distinct mechanism for matter creation. WUM is proposed as an alternative to the prevailing BBM. Its main advantage is the elimination of the “Initial Singularity” and “Inflation”, offering explanations for many unresolved problems in Cosmology. WUM is presented as a natural extension of Classical Physics with the potential to bring about a significant transformation in both Cosmology and Classical Physics. Considering JWST’s discoveries, WUM’s achievements, and 87 years of Dirac’s proposals, it is time to initiate a fundamental transformation in Astronomy, Cosmology, and Classical Physics. The present paper is a continuation of the published article “JWST Discoveries—Confirmation of World-Universe Model Predictions” [2] and a summary of the paper “Hypersphere World-Universe Model: Digest of Presentations John Chappell Natural Philosophy Society” [3]. Many results obtained there are quoted in the current work without full justification;interested readers are encouraged to view the referenced papers for detailed explanations. 展开更多
关键词 World-Universe model JWST Discoveries Universe-Created Matter Gravity GRAVITOMAGNETISM Wave-Particle Duality Hubble tension Stretching of World Dark Epoch Luminous Epoch Axis of Evil
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Calculation of Particle Decay Times in the Standard Model
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作者 Jan Helm 《Journal of Modern Physics》 2024年第3期271-321,共51页
We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experi... We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experimental formula for decay width originally introduced by Chang. This schematic formula separates decays into seven classes. Furthermore, from it is derived a process-specific interaction energy m<sub>X</sub>. The second step is a numerical calculation method, which calculates this interaction energy m<sub>X</sub> numerically by minimization of action from the Lagrangian of the process, from which follows the decay width via the phenomenological formula. The Lagrangian is based on an extension of the Standard Model, the extended SU(4)-preon-model. A comparison of numerically calculated and observed decay widths for a large selection of decays shows a good agreement. 展开更多
关键词 Particle Decay Decay Width Interaction Energy Minimization of Action Ex-tension of Standard model
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Indirect tension test of epoxy asphalt mixtureusing microstructural finite-element model 被引量:8
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作者 王江洋 钱振东 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期65-69,共5页
A finite-element model of the thermosetting epoxy asphalt mixture(EAM) microstructure is developed to simulate the indirect tension test(IDT).Image techniques are used to capture the EAM microstructure which is di... A finite-element model of the thermosetting epoxy asphalt mixture(EAM) microstructure is developed to simulate the indirect tension test(IDT).Image techniques are used to capture the EAM microstructure which is divided into two phases:aggregates and mastic.A viscoelastic constitutive relationship,which is obtained from the results of a creep test,is used to represent the mastic phase at intermittent temperatures.Model simulation results of the stiffness modulus in IDT compare favorably with experimental data.Different loading directions and velocities are employed in order to account for their influence on the modulus and the localized stress of the microstructure model.It is pointed out that the modulus is not consistent when the loading direction changes since the heterogeneous distribution of the mixture internal structure,and the loading velocity affects the localized stress as a result of the viscoelasticity of the mastic.The study results can provide a theoretical basis for the finite-element method,which can be extended to the numerical simulations of asphalt mixture micromechanical behavior. 展开更多
关键词 MICROSTRUCTURE epoxy asphalt mixture image techniques finite-element model indirect tension test
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Calculating models on surface tension of RE_2O_3-Mg O-SiO_2(RE=La, Nd, Sm, Gd and Y) melts 被引量:2
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作者 吴铖川 成国光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3696-3701,共6页
A thermodynamic model was developed for determining the surface tension of RE2O3-MgO-SiO2(RE=La, Nd, Sm, Gd and Y) melts considering the ionic radii of the components and Butler's equation. The temperature and com... A thermodynamic model was developed for determining the surface tension of RE2O3-MgO-SiO2(RE=La, Nd, Sm, Gd and Y) melts considering the ionic radii of the components and Butler's equation. The temperature and composition dependence of the surface tensions in molten RE2O3-MgO-SiO2 slag systems was reproduced by the present model using surface tensions and molar volumes of pure oxides, as well as the anionic and cationic radii of the melt components. The iso-surface tension lines of La2O3-MgO-SiO2 slag melt at 1873 K were calculated and the effects of slag composition on the surface tension were also investigated. The surface tensions of La2O3, Gd2O3, Nd2O3 and Y2O3 at 1873 K were evaluated as 686, 677, 664 and 541 m N/m, respectively. The surface tension of pure rare earth oxide melts linearly decreases with increasing cationic field strength, except for Y2O3 oxide, while Y2O3 has a much weaker surface tension. The evaluated results of the surface tension show good agreements with literature data, and the mean deviation of the present model is found to be 1.05% at 1873 K. 展开更多
关键词 rare-earth oxide surface tension ionic radius Butler's equation calculating model
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Calculation Model for Surface Tension of Slag Melt 被引量:8
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作者 Cheng Guoguang Liao Nengbin 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1999年第2期17-20,共3页
Based on the coexistence theory of slag melt structure and Butler’s equation,a new calculation model has been proposed for the calculation of surface tension of slag melt.This model establishes a specific correlation... Based on the coexistence theory of slag melt structure and Butler’s equation,a new calculation model has been proposed for the calculation of surface tension of slag melt.This model establishes a specific correlation between surface tension and mass action concentrations(activities) in the melt and on its surface on the basis of inner and surficial structures of slag melt.Calculated surface tensions of CaO-SiOand MnO-SiOslag melts are consistent with those measured.Furthermore,iso-surface tension lines of CaO-MnO-SiOslag melt have also been calculated. 展开更多
关键词 slag melt surface tension ACTIVITY model
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Modeling bubble column reactor with the volume of fluid approach:Comparison of surface tension models 被引量:4
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作者 Qi Liu Zhenghong Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2659-2665,共7页
This work aims at comparing surface tension models in VOF(Volume of Fluid) modeling and investigating the effects of gas distributor and gas velocity. Hydrodynamics of a continuous chain of bubbles inside a bubble col... This work aims at comparing surface tension models in VOF(Volume of Fluid) modeling and investigating the effects of gas distributor and gas velocity. Hydrodynamics of a continuous chain of bubbles inside a bubble column reactor was simulated. The grid independence study was first conducted and a grid size of 1.0 mm was adopted in order to minimize the computing time without compromising the accuracy of the results. The predictions were validated by comparing the experimental studies reported in the literature. It was found that all surface tension models can describe the bubble rise and bubble plume in a column with slight deviations. 展开更多
关键词 BUBBLE COLUMN reactor Computational FLUID dynamics Volume of FLUID method Surface tension modelS Gas DISTRIBUTOR
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A Molecular Thermodynamic Model for Interfacial Tension in Surfactant-Oil-Water System 被引量:2
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作者 付东 包铁竹 +2 位作者 陆九芳 李以圭 李小森 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第2期154-158,共5页
An interfacial equation of state based on perturbation theory for surfactant-oil-water system has been developed. By combining the interfacial equation of state with Boudh-Hir and Mansoori's model, a molecular the... An interfacial equation of state based on perturbation theory for surfactant-oil-water system has been developed. By combining the interfacial equation of state with Boudh-Hir and Mansoori's model, a molecular ther-modynamic model has been proposed. The interfacial tension of surfactant-oil-water systems can be calculated from the surface tensions of pure oil and water by this model. The interfacial tension data for sodium dodecyl sulphate-heptane-water system, polyoxyethylene n-octylphenol-heptane-water system and hexadecyl trimethyl ammonium bromide-heptane-water system have been correlated. By using the adjustable parameters obtained, the interfacial tensions of these systems at other temperatures have been predicted. Both the correlated and the predicted values are satisfactory. 展开更多
关键词 interfaciai tension molecular thermodynamic model perturbation theory surfactant-oil-water system
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A 3-DOF Pseudo-Rigid-Body Model for Tension-Based Compliant Bistable Mechanisms 被引量:1
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作者 CHEN Guimin GAO Hongwei JIA Jianyuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第2期149-153,共5页
Compliant bistable mechanisms, devices with two distinct stable equilibrium positions, are used in a variety of applications, such as switches, clasps, and valves. Many kinds of compliant bistable mechanisms were prop... Compliant bistable mechanisms, devices with two distinct stable equilibrium positions, are used in a variety of applications, such as switches, clasps, and valves. Many kinds of compliant bistable mechanisms were proposed and studied during the past decade. Among them, tension-based compliant bistable mechanisms, that incorporate tension pivots as their flexible members, feature in short travel distance and low power consuming. So far, the design of this kind of bistable mechanisms is done using finite element method through trial and error, thus is time-consuming. By treating the tension pivots as fixed-guided segments and their elongation as a spring, we developed a novel three degree-of-freedom (3-DOF) pseudo-rigid-body model (PRBM) for this kind of bistable mechanisms. The principle of virtual work is used to derive the force-deflection relationship of the PRBM model. The comparison between the PRBM results and the experimental results of the force-deflection characteristics shows that the PRBM can predict not only the bistable behavior of the tension-based bistable mechanisms, but also their soft spring-like post-bistable behavior and the spring-like force-deflection characteristics when pulling in the reverse direction from the as-fabricated position, which is called reverse behavior. The 3-DOF PRBM can be used to design and identify tension-based bistable mechanisms. Using the PRBM instead of the trial-and-error method can greatly reduce the development time of this kind of bistable mechanisms. 展开更多
关键词 compliant bistable mechanism pseudo-rigid-body model tension pivot
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Modified surface tension model for free surface flow with single-phase lattice Boltzmann method 被引量:1
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作者 严永华 杨帆 +1 位作者 钱忠东 钱跃竑 《Journal of Shanghai University(English Edition)》 CAS 2010年第2期145-149,共5页
A single-phase lattice Boltzmann model with modified surface tension is developed in this paper to solve the problem of high-density-ratio free surface flow.The computational efficiency and accuracy are both enhanced.... A single-phase lattice Boltzmann model with modified surface tension is developed in this paper to solve the problem of high-density-ratio free surface flow.The computational efficiency and accuracy are both enhanced.The restriction to the relaxation factor (which needs to be smaller than 1) is circumvented by the new surface tension algebra,due to its rational physical nature compared with the treatment of Xing,Buther and Yang in their paper (Comp.Mater.Sci.,2007,39(2):282-290).The proposed stable surface tension scheme is applied to simulate the free deformation of a square droplet with surface tension effect and the process of a droplet impinging on a liquid film.The numerical solution for free deformation of a droplet agrees well with thermodynamic principles,and also achieves high accuracy in comparison with Xing,et al.'s model.Three typical impinging modes are successfully obtained with the new scheme,and another particular mode found by Wang and Chen is also successfully simulated.The evolutions of liquid crown agree well with the power law related to time. 展开更多
关键词 surface tension lattice Boltzmann model (LBM) single-phase model high density ratio free surface DROPLET
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A Surface Tension Model for Liquid Mixtures Based on NRTL Equation 被引量:1
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作者 李春喜 汪文川 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第1期45-50,共6页
A new equation for predicting surface tension is proposed based on the thermodynamic definition of surface tension and the expression of the Gibbs free energy of the system. Using the NRTL equation to represent the ex... A new equation for predicting surface tension is proposed based on the thermodynamic definition of surface tension and the expression of the Gibbs free energy of the system. Using the NRTL equation to represent the excess Gibbs free energy, a two-parameter surface tension equation is derived. The feasibility of the new equation has been tested in terms of 124 binary and 16 multicomponent systems(13-ternary and 3-quaternary) with absolute relative deviations of 0.59% and 1.55% respectively. This model is also predictive for the temperature dependence of surface tension of liquid mixtures. It is shown that, with good accuracy, this equation is simple and reliable for practical use. 展开更多
关键词 model surface tension liquid mixtures Gibbs free energy NRTL equation
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The mathematic model of tension straightening process of magnesium alloy and experimental validation 被引量:1
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作者 Yan Jing Zhang Ding-fei +2 位作者 Wang Xiao-hong Peng Jian Yang Lin 《Journal of Magnesium and Alloys》 SCIE EI CAS 2013年第1期76-81,共6页
The stress-strain curve of bending bar and the stress relax curve of AZ31 was obtained by a tension test using Gleeble-1500.The tension straightening process mainly consisted of the elastic loading-I and unloading sta... The stress-strain curve of bending bar and the stress relax curve of AZ31 was obtained by a tension test using Gleeble-1500.The tension straightening process mainly consisted of the elastic loading-I and unloading stage,the elastic loading-II and unloading stage,and the elastic-plastic loading stage,which were based on the stretch force change during straightening.The circular bar straightening under one-dimensional bending was investigated and assumed to be linear strain-hardening elastic-plastic material.According to the elastic-plastic mechanics theory,the mathematical displacement-force model of a tension straightening process established,on which was based,the predicted displacement of tension straightening for various original deflection was calculated.The tension straightening experiment for AZ31 magnesium was conducted under the guidance of the predicted displacement.The experiment results present good straightness when there is a stress relaxation phenomenon or the temperature of tension straightening is 25℃. 展开更多
关键词 tension straightening Mathematic model Linear strain-hardening elasticeplastic material Stress relaxation AZ31 magnesium
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A Kinetic Model for Describing the Effect of Proteins on the Air-Water Interface Tension 被引量:1
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作者 Luis Alberto Panizzolo Luis Eduardo Mussio Maria Cristina Anon 《Journal of Food Science and Engineering》 2014年第6期282-290,共9页
The main objective of this work was to develop a kinetic model to describe the variation of the surface tension in an air-water interface due to the adsorption of proteins from different origins and to identify quanti... The main objective of this work was to develop a kinetic model to describe the variation of the surface tension in an air-water interface due to the adsorption of proteins from different origins and to identify quantitatively the relevant parameters, it was considered that the processes of adsorption, unfolding and reordering of the protein molecule in the interface occur simultaneously. The model used in the present work to calculate the surface tension postulates the existence of two simultaneous processes, adsorption and protein rearrangement represented with an equation of first order with two exponential components. The relevant parameter of the equation are ka and kr-the rate constants of the two first order kinetic phases that correspond to both conformational states of the protein, adsorption and rearrangement during the process of variation of the surface tension, and the amplitude parameters Aa and Ar. The results suggest that the kinetic model for the variation of the surface tension of protein solutions proposed in this work, with two simultaneous first order processes, is more appropriate than previous models to describe such variation. 展开更多
关键词 Interface tension PROTEINS kinetic model.
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Simplified Prediction Model for Vortex-Induced Vibrations of Top Tensioned Risers 被引量:4
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作者 薛鸿祥 唐文勇 张圣坤 《China Ocean Engineering》 SCIE EI 2008年第2期291-302,共12页
According to the characteristics of deepwater top tensioned risers, a simplified model is presented to predict the multi-modal response of vortex-induced vibration (VIV) in non-uniform flow based on energy equilibri... According to the characteristics of deepwater top tensioned risers, a simplified model is presented to predict the multi-modal response of vortex-induced vibration (VIV) in non-uniform flow based on energy equilibrium theory and the exporimental data from VIV self-excited and forced oscillations of rigid cylinders. The response amplitude of each mode is determined by a balance between the energy fed into the riser over the lock-in regions and the energy dissipated by the fluid damping over the remainders. Compared with the previous prediction models, this method can take fully account of the intrinsic nature of VIV for low mass ratio structures on lock-in regions, added mass and nonlinear fluid damping effect, etc. Moreover, it is the first time to propose the accurate calculating procedure for VIV amplitude correction factor by solving energy equilibrium equation and a closed form solution is presented for the case of a riser of uniform mass and cross-section oscillating in a uniform flow. The predicted values show a reasonable agreement with VIV experiments of riser models in stepped and sheared currents. 展开更多
关键词 top-tensioned riser vortex-induced vibration LOCK-IN simplified prediction model
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Hydrodynamic Response of A Fully Coupled TLP Hull-TTR System with Detailed Modeling of A Hydraulic Pneumatic Tensioner and Riser Joints
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作者 HAO Shuai YU Yang +2 位作者 YU Jian-xing YUAN Zhi-ming XU Li-xin 《China Ocean Engineering》 SCIE EI CSCD 2022年第3期451-463,共13页
Tension Leg Platform(TLP)in deepwater oil and gas field development usually consists of a hull,tendons,and top tension risers(TTRs).To maintain its top tension,each TTR is connected with a tensioner system to the hull... Tension Leg Platform(TLP)in deepwater oil and gas field development usually consists of a hull,tendons,and top tension risers(TTRs).To maintain its top tension,each TTR is connected with a tensioner system to the hull.Owing to the complicated configuration of the tensioners,the hull and TTRs form a strong coupled system.Traditionally,some simplified tensioner models are applied to analyze the TLP structures.There is a large discrepancy between their analysis results and the actual mechanism behaviors of a tensioner.It is very necessary to develop a more detailed tensioner model to consider the coupling effects between TLP and TTRs.In the present study,a fully coupled TLP hull-TTR system for hydrodynamic numerical simulation is established.A specific hydraulic pneumatic tensioner is modeled by considering 4 cylinders.The production TTR model is stacked up by specific riser joints.The simulation is also extended to analyze an array of TTRs.Different regular and irregular waves are considered.The behaviors of different cylinders are presented.The results show that it is important to consider the specific configurations of the tensioner and TTRs,which may lead to obviously different response behaviors,compared with those from a simplified model. 展开更多
关键词 top tension riser(TTR) fully coupled hull-tendon-TTR-tensioner model hydraulic pneumatic tensioner hydrodynamic response 3D potential flow theory
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Interroll tension model adapted to a secondary annealing process
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作者 ZHANG Ran 《Baosteel Technical Research》 CAS 2021年第3期9-16,共8页
Due to the special secondary rolling and annealing processes,the physical properties of strip ductility and stress relief differ from those of the general products.The proportional integral differential(PID)algorithm ... Due to the special secondary rolling and annealing processes,the physical properties of strip ductility and stress relief differ from those of the general products.The proportional integral differential(PID)algorithm for the annealing furnace tension control and the conventional control method that only controls the total tension of the furnace entrance and exit cannot meet production continuity.Aiming at the tension in the annealing furnace,the interroll tension model of the tension of the steel strip between the adjacent furnace rolls is established.By combining the control principle of the annealing furnace roll transmission mechanism,the tension control involves the motor and frequency converter equipment.The coupling relationship between the stator current and the motor’s output torque was determined through the asynchronous equivalent motor circuit.Also,the direct influence of the load torque on the calculated value of the motor’s output tension was obtained through the motor vector control equation.Furthermore,the frequency converter’s voltage control model was analyzed to control the motor’s output tension.Finally,the adjacent furnace roll tension and the horizontal annealing furnace tension were calculated through the interroll tension model. 展开更多
关键词 asynchronous motor vector control tension model
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Calculating Models on the Surface Tension of CaO-FeO-SiO2 Molten Slags 被引量:2
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作者 Chengchuan Wu 《材料科学研究(中英文版)》 2014年第1期10-16,共7页
关键词 二氧化硅基 表面张力 计算模型 熔渣 炉渣结构 炉渣成分 热力学模型 共存理论
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基于修正断裂分析模型的混凝土劈拉强度预测
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作者 金浏 韩丛熹 +1 位作者 李冬 杜修力 《工程力学》 EI CSCD 北大核心 2024年第7期29-39,98,共12页
数值分析是规避试验短板、实现理论预期的重要研究手段。该文采用细观尺度数值试验方法,对建立的基于绕晶失效模式的混凝土三维细观断裂理论分析模型进行修正。采用的混凝土数值分析模型由砂浆、界面及骨料组成,与理论分析模型保持一致... 数值分析是规避试验短板、实现理论预期的重要研究手段。该文采用细观尺度数值试验方法,对建立的基于绕晶失效模式的混凝土三维细观断裂理论分析模型进行修正。采用的混凝土数值分析模型由砂浆、界面及骨料组成,与理论分析模型保持一致。为模拟普通强度混凝土的力学行为,采用塑性损伤本构模型表征砂浆和界面的力学性能,骨料则设为弹性球体。采用自编骨料投放程序,建立了截面尺寸分别为100 mm(一级配)、150 mm(二级配)、300 mm(三级配)和450 mm(四级配)的三维模型混凝土标准立方体试件。通过开展不同界面强度条件下标准立方体试件劈裂拉伸加载数值试验,对理论分析模型进行了修正,建立了用于不同级配混凝土劈拉强度预测的半理论-半经验修正计算公式。与数值试验及物理试验结果对比表明:修正后的理论分析模型能够有效表征混凝土宏观力学性能随细观组成材料力学特性和结构特性的变化规律。该文提出的基于重叠效应和结构效应分析的理论模型修正方法,可为后续建立基于修正断裂分析模型的混凝土力学性能半理论-半经验预测公式奠定基础。 展开更多
关键词 混凝土 非均质性 细观模拟 劈裂拉伸 塑性损伤模型
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