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Star Movement Is Not Predicted Two-Compartment Model of the Universe
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作者 Philip D. Houck 《Journal of Modern Physics》 2024年第11期1679-1689,共11页
A two-compartment model of the universe is proposed to further refine Albert Einstein’s insight into curvature of space and the energy tensor. The two compartments are energy contained by a shell prism. The model all... A two-compartment model of the universe is proposed to further refine Albert Einstein’s insight into curvature of space and the energy tensor. The two compartments are energy contained by a shell prism. The model allows for a non-unification of fundamental forces with gravity resulting from the curvature of a space-time prism. Carrier forces travel within the prism and particles emerge from the prism. Giving a thickness to the manifold negates infinity and will allow solutions at both microscopic and cosmic levels. Geometry is the link between quantum mechanics and general relativity. Negative entropy, as proposed by Erwin Schrödinger, gives order to particles and the cosmic. The source of this energy is in the shell of the containment vessel. The acceleration of the expansion of the universe occurred when energy within the container transformed into mass, warping the space-time container and causing an explosion of the container. Star movement is explained by the surface tension of the prism of space-time. 展开更多
关键词 two-Compartment Model Negative Entropy GEOMETRY
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Gradient Recovery Based Two-Grid Finite Element Method for Parabolic Integro-Differential Optimal Control Problems
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作者 Miao Yang 《Journal of Applied Mathematics and Physics》 2024年第8期2849-2865,共17页
In this paper, the optimal control problem of parabolic integro-differential equations is solved by gradient recovery based two-grid finite element method. Piecewise linear functions are used to approximate state and ... In this paper, the optimal control problem of parabolic integro-differential equations is solved by gradient recovery based two-grid finite element method. Piecewise linear functions are used to approximate state and co-state variables, and piecewise constant function is used to approximate control variables. Generally, the optimal conditions for the problem are solved iteratively until the control variable reaches error tolerance. In order to calculate all the variables individually and parallelly, we introduce a gradient recovery based two-grid method. First, we solve the small scaled optimal control problem on coarse grids. Next, we use the gradient recovery technique to recover the gradients of state and co-state variables. Finally, using the recovered variables, we solve the large scaled optimal control problem for all variables independently. Moreover, we estimate priori error for the proposed scheme, and use an example to validate the theoretical results. 展开更多
关键词 Optimal Control Problem Gradient Recovery two-Grid Finite Element Method
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Effective Qubit Emerging from the Nanoheterointerface Two-Dimensional Electron Gas Photodynamics
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作者 Emmanuel A. Anagnostakis 《Journal of Modern Physics》 2024年第11期1615-1620,共6页
An “Eigenstate Adjustment Autonomy” Model, permeated by the Nanosystem’s Fermi Level Pinning along with its rigid Conduction Band Discontinuity, compatible with pertinent Experimental Measurements, is being employe... An “Eigenstate Adjustment Autonomy” Model, permeated by the Nanosystem’s Fermi Level Pinning along with its rigid Conduction Band Discontinuity, compatible with pertinent Experimental Measurements, is being employed for studying how the Functional Eigenstate of the Two-Dimensional Electron Gas (2DEG) dwelling within the Quantum Well of a typical Semiconductor Nanoheterointerface evolves versus (cryptographically) selectable consecutive Cumulative Photon Dose values. Thus, it is ultimately discussed that the experimentally observed (after a Critical Cumulative Photon Dose) Phenomenon of 2DEG Negative Differential Mobility allows for the Nanosystem to exhibit an Effective Qubit Specific Functionality potentially conducive to (Telecommunication) Quantum Information Registering. 展开更多
关键词 Semiconductor Nanoheterointerface two-Dimensional Electron Gas Nanosystem Photodynamics Sign Qubit Quantum Information Registering
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Numerical Solutions of the Classical and Modified Buckley-Leverett Equations Applied to Two-Phase Fluid Flow
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作者 Raphael de O. Garcia Graciele P. Silveira 《Open Journal of Fluid Dynamics》 2024年第3期184-204,共21页
Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on t... Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on the subject, given the emergencies related to climate. An energy transition to clean and renewable sources is necessary and urgent, but it will not be quick. In this sense, increasing the efficiency of oil extraction from existing sources is crucial, to avoid waste and the drilling of new wells. The purpose of this work was to add diffusive and dispersive terms to the Buckley-Leverett equation in order to incorporate extra phenomena in the temporal evolution between the water-oil and oil-water transitions in the pipeline. For this, the modified Buckley-Leverett equation was discretized via essentially weighted non-oscillatory schemes, coupled with a three-stage Runge-Kutta and a fourth-order centered finite difference methods. Then, computational simulations were performed and the results showed that new features emerge in the transitions, when compared to classical simulations. For instance, the dispersive term inhibits the diffusive term, adding oscillations, which indicates that the absorption of the fluid by the porous medium occurs in a non-homogeneous manner. Therefore, based on research such as this, decisions can be made regarding the replacement of the porous medium or the insertion of new components to delay the replacement. 展开更多
关键词 Computational Fluid Dynamics Buckley-Leverett Equation Numerical Methods two-phase Fluid Flow
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A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
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作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) INVENTORY Time-Proportional Deterioration two-Phased Demand
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Nash Equilibrium of a Fixed-Sum Two-Player Game
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作者 Yoshihiro Tanaka 《American Journal of Computational Mathematics》 2024年第3期346-357,共12页
It is well established that Nash equilibrium exists within the framework of mixed strategies in strategic-form non-cooperative games. However, finding the Nash equilibrium generally belongs to the class of problems kn... It is well established that Nash equilibrium exists within the framework of mixed strategies in strategic-form non-cooperative games. However, finding the Nash equilibrium generally belongs to the class of problems known as PPAD (Polynomial Parity Argument on Directed graphs), for which no polynomial-time solution methods are known, even for two-player games. This paper demonstrates that in fixed-sum two-player games (including zero-sum games), the Nash equilibrium forms a convex set, and has a unique expected payoff. Furthermore, these equilibria are Pareto optimal. Additionally, it is shown that the Nash equilibrium of fixed-sum two-player games can theoretically be found in polynomial time using the principal-dual interior point method, a solution method of linear programming. 展开更多
关键词 Nash Equilibrium Fixed-Sum two-Player Game Principal-Dual Interior Point Method
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The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem
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作者 Bijay Kumar Sharma 《International Journal of Astronomy and Astrophysics》 2024年第1期1-19,共19页
Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubatio... Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius a<sub>H</sub> and planet mean radius R<sub>P </sub>and the ratio R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub>. Under very low R<sub>1 </sub>(less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub> =0.01 and 5.9862 × 10<sup>-3</sup> respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study. 展开更多
关键词 Hill’s Radius two-Body Problem Fixed-Point Solution Lagrange Points Earth-Moon-Test Particle CRTBP
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Multi-Granularity Neighborhood Fuzzy Rough Set Model on Two Universes
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作者 Ju Wang Xinghu Ai Li Fu 《Journal of Intelligent Learning Systems and Applications》 2024年第2期91-106,共16页
The two universes multi-granularity fuzzy rough set model is an effective tool for handling uncertainty problems between two domains with the help of binary fuzzy relations. This article applies the idea of neighborho... The two universes multi-granularity fuzzy rough set model is an effective tool for handling uncertainty problems between two domains with the help of binary fuzzy relations. This article applies the idea of neighborhood rough sets to two universes multi-granularity fuzzy rough sets, and discusses the two-universes multi-granularity neighborhood fuzzy rough set model. Firstly, the upper and lower approximation operators are defined in the two universes multi-granularity neighborhood fuzzy rough set model. Secondly, the properties of the upper and lower approximation operators are discussed. Finally, the properties of the two universes multi-granularity neighborhood fuzzy rough set model are verified through case studies. 展开更多
关键词 Fuzzy Set two Universes Multi-Granularity Rough Set Multi-Granularity Neighborhood Fuzzy Rough Set
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“N-Two-N”教学模式的构建及在本科有机化学教学中的探究实践
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作者 李万梅 欧阳娅妮 章鹏飞 《大学化学》 CAS 2023年第11期54-63,共10页
基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPP... 基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPPS模式改革教学过程,结合多种教学法和多种评价方式,构建一个“N-Two-N”一体化的课堂教学体系。本文阐述了“N-Two-N”一体化模式的落实过程以及该教学模式的优点和取得的成效。 展开更多
关键词 “N-two-N”模式 CDIO-BOPPPS协同教学 立德树人 教学方法 有机化学
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Analysis of College Students’ Test Scores Based on Two-Component Mixed Generalized Normal Distribution
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作者 Luliang Wen Haiwu Rong Yanjun Qiu 《Journal of Data Analysis and Information Processing》 2023年第1期69-80,共12页
In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditiona... In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditional Maxinnization (ECM) algorithm to estimate parameters and conduct numerical simulation, and performs fitting analysis on the test scores of Linear Algebra and Advanced Mathematics of F University. The empirical results show that the two-component mixed generalized normal distribution is better than the commonly used two-component mixed normal distribution in fitting college students’ test data, and has good application value. 展开更多
关键词 two-Component Mixed Generalized Normal Distribution two-Component Mixed Normal Distribution ECM Algorithm Test Scores
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AN ANALYTIC SOLUTION OF DENSE TWO-PHASE FLOW IN A VERTICAL PIPELINE
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作者 林多敏 蔡树棠 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第12期1095-1103,共9页
According to a mathematical model for dense two-phase flows presented in the previous pape[1],a dense two-phase flow in a vertical pipeline is analytically solved, and the analytic expressions of velocity of each cont... According to a mathematical model for dense two-phase flows presented in the previous pape[1],a dense two-phase flow in a vertical pipeline is analytically solved, and the analytic expressions of velocity of each continuous phase and dispersed phase are respectively derived. The results show that when the drag force between twophasesdepends linearly on their relative velocity, the relative velocity profile in the pipeline coincides with Darcy's law except for the thin layer region near the pipeline wall, and that the theoretical assumptions in the dense two-phase flow theory mentioned are reasonable. 展开更多
关键词 dense two-phase flow vertical pipe two-phase flow two-phase flow analytical solution two-phase flow model application
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Two-Agent Makespan Minimization Problem on Parallel Machines
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作者 Siqi Zheng Zhaohui Liu 《Journal of Applied Mathematics and Physics》 2023年第6期1693-1706,共14页
A two-agent scheduling problem on parallel machines is considered in this paper. Our objective is to minimize the makespan for agent A, subject to an upper bound on the makespan for agent B. In this paper, we provide ... A two-agent scheduling problem on parallel machines is considered in this paper. Our objective is to minimize the makespan for agent A, subject to an upper bound on the makespan for agent B. In this paper, we provide a new approximation algorithm called CLPT. On the one hand, we compare the performance between the CLPT algorithm and the optimal solution and find that the solution obtained by the CLPT algorithm is very close to the optimal solution. On the other hand, we design different experimental frameworks to compare the CLPT algorithm and the A-LS algorithm for a comprehensive performance evaluation. A large number of numerical simulation results show that the CLPT algorithm outperformed the A-LS algorithm. 展开更多
关键词 Parallel Machines MAKESPAN Approximation Algorithm two-Agent Empirical Results
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Modeling One Dimensional Two-Cell Model with Tumor Interaction Using Krylov Subspace Methods
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作者 Ibtisam Alqahtani Sharefa Eisa Ali Alhazmi 《Applied Mathematics》 2023年第1期21-34,共14页
A brain tumor occurs when abnormal cells grow, sometimes very rapidly, into an abnormal mass of tissue. The tumor can infect normal tissue, so there is an interaction between healthy and infected cell. The aim of this... A brain tumor occurs when abnormal cells grow, sometimes very rapidly, into an abnormal mass of tissue. The tumor can infect normal tissue, so there is an interaction between healthy and infected cell. The aim of this paper is to propose some efficient and accurate numerical methods for the computational solution of one-dimensional continuous basic models for the growth and control of brain tumors. After computing the analytical solution, we construct approximations of the solution to the problem using a standard second order finite difference method for space discretization and the Crank-Nicolson method for time discretization. Then, we investigate the convergence behavior of Conjugate gradient and generalized minimum residual as Krylov subspace methods to solve the tridiagonal toeplitz matrix system derived. 展开更多
关键词 PDES Krylov Subspace Methods Finite Difference Toeplitz Matrix two-Cell Model Tumor Interaction Modeling
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Hopf Bifurcation of Nonresident Computer Virus Model with Age Structure and Two Delays Effects
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作者 Yaoyu Dang Hongwu Tan Hui Cao 《Journal of Applied Mathematics and Physics》 2023年第8期2318-2342,共25页
This paper constructed and studied a nonresident computer virus model with age structure and two delays effects. The non-negativity and boundedness of the solution of the model have been discussed, and then gave the b... This paper constructed and studied a nonresident computer virus model with age structure and two delays effects. The non-negativity and boundedness of the solution of the model have been discussed, and then gave the basic regeneration number, and obtained the conditions for the existence and the stability of the virus-free equilibrium and the computer virus equilibrium. Theoretical analysis shows the conditions under which the model undergoes Hopf bifurcation in three different cases. The numerical examples are provided to demonstrate the theoretical results. 展开更多
关键词 The Computer Virus Model AGE-STRUCTURE two Delays Stability Hopf Bifurcation
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Heat and Mass Transfers in a Two-Phase Stratified Turbulent Fluid Flow in a Geothermal Pipe with Chemical Reaction
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作者 Eric M. Nyariki Mathew N. Kinyanjui Jeconia O. Abonyo 《Journal of Applied Mathematics and Physics》 2023年第2期484-513,共30页
This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing... This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing the flow were solved using the Finite Difference Method. The effects of various physical parameters on the concentration, skin friction, heat, and mass transfers have been determined. Analysis of the results obtained indicated that the coefficient of skin friction decreased with an increase in Reynolds number and solutal Grasholf number, the rate of heat transfer increased with an increase in Eckert number, Prandtl number, and angle of inclination, and the rate of mass transfer increased with increase in Reynolds number, Chemical reaction parameter and angle of inclination. The findings would be useful to engineers in designing and maintaining geothermal pipelines more effectively. 展开更多
关键词 two-PHASE Turbulence Non-Newtonian INCLINATION Heat Transfer Mass Transfer STRATIFIED
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Development and Evaluation of Intersection-Based Turning Movement Counts Framework Using Two Channel LiDAR Sensors
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作者 Ravi Jagirdar Joyoung Lee +2 位作者 Dejan Besenski Min-Wook Kang Chaitanya Pathak 《Journal of Transportation Technologies》 2023年第4期524-544,共21页
This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse ... This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities. 展开更多
关键词 Vehicle Trajectory Construction two Channel LiDAR Turning Movement Counts RTMS Smart Cities LIDAR
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求解二阶锥绝对值方程组的惯性two-sweep迭代法
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作者 洪晓曼 唐嘉 《武夷学院学报》 2023年第9期1-6,共6页
提出一种求解二阶锥绝对值方程组(SOCAVE)的惯性two-sweep迭代法。通过引入一个惯性项和一个恒等式,在系统矩阵和迭代矩阵满足一定条件的情况下,分析该算法的收敛性,数值结果表明所提出的方法是可行且有效的。
关键词 two-sweep迭代法 二阶锥 绝对值方程 惯性项
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A Posteriori Error Estimate of Two Grid Mixed Finite Element Methods for Semilinear Elliptic Equations
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作者 Yiming Wen Luoping Chen Jiajia Dai 《Journal of Applied Mathematics and Physics》 2023年第2期361-376,共16页
In this paper, we present the a posteriori error estimate of two-grid mixed finite element methods by averaging techniques for semilinear elliptic equations. We first propose the two-grid algorithms to linearize the m... In this paper, we present the a posteriori error estimate of two-grid mixed finite element methods by averaging techniques for semilinear elliptic equations. We first propose the two-grid algorithms to linearize the mixed method equations. Then, the averaging technique is used to construct the a posteriori error estimates of the two-grid mixed finite element method and theoretical analysis are given for the error estimators. Finally, we give some numerical examples to verify the reliability and efficiency of the a posteriori error estimator. 展开更多
关键词 two-Grid Mixed Finite Element Methods Posteriori Error Estimates Semilinear Elliptic Equations Averaging Technique
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Predictive Characteristics of Co-authorship Networks: Comparing the Unweighted, Weighted, and Bipartite Cases
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作者 Raf Guns 《Journal of Data and Information Science》 2016年第3期59-78,共20页
Purpose: This study aims to answer the question to what extent different types of networks can be used to predict future co-authorship among authors.Design/methodology/approach: We compare three types ot networks: ... Purpose: This study aims to answer the question to what extent different types of networks can be used to predict future co-authorship among authors.Design/methodology/approach: We compare three types ot networks: unwelgntea networks, in which a link represents a past collaboration; weighted networks, in which links are weighted by the number of joint publications; and bipartite author-publication networks. The analysis investigates their relation to positive stability, as well as their potential in predicting links in future versions of the co-authorship network. Several hypotheses are tested.Findings: Among other results, we find that weighted networks do not automatically lead to better predictions. Bipartite networks, however, outperform unweighted networks in almost all cases. Research limitations: Only two relatively small case studies are considered Practical implications: The study suggests that future link prediction studies on networks should consider using the bipartite network as a training network. Originality/value: This is the first systematic comparison of unweighted, weighted, and bipartite training networks in link prediction. 展开更多
关键词 Network evolution Link prediction Weighted networks Bipartite networks two-mode networks
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Production of χc and ηc in Ultra-Peripheral Collisions with Two-Photon Processes
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作者 Gongming Yu Yanbing Cai +1 位作者 Quangui Gao Qiang Hu 《Journal of Modern Physics》 2023年第12期1634-1640,共7页
We calculate the production of χ<sub>c</sub> and η<sub>c</sub> by the two-photon process in ultra-peripheral heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Co... We calculate the production of χ<sub>c</sub> and η<sub>c</sub> by the two-photon process in ultra-peripheral heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies. The differential cross section of transverse momentum distribution and rapidity distribution for (H = χ<sub>c</sub> and η<sub>c</sub>), are estimated by using the equivalent photon flux in the impact parameter space. The numerical results indicate that the study of χ<sub>c</sub> and η<sub>c</sub> in ultra-peripheral heavy ion collisions are feasible at RHIC and LHC energies. 展开更多
关键词 CHARMONIUM two-Photon Processes Ultra-Peripheral Collisions
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