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New Asymptotic Results on Fermat-Wiles Theorem
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作者 Kimou Kouadio Prosper Kouakou Kouassi Vincent Tanoé François 《Advances in Pure Mathematics》 2024年第6期421-441,共21页
We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Dio... We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Diophantine remainders of (a, b, c), an asymptotic approach based on Balzano Weierstrass Analysis Theorem as tools. We construct convergent infinite sequences and establish asymptotic results including the following surprising one. If z y = 1 then there exists a tight bound N such that, for all prime exponents p > N , we have xp yp zp. 展开更多
关键词 Fermat’s Last Theorem Fermat-Wiles Theorem Kimou’s Divisors Diophantine Quotient Diophantine Remainders Balzano Weierstrass Analysis Theorem
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Physico-Chemical and Nutritional Properties of a Food Broth Based on Nere (Parkia biglobosa)
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作者 Lassana Bamba Gervais Melaine M’Boh +5 位作者 N’Gbésso Amos Ekissi Kipré Laurent Séri Gnogbo Alexis Bahi Koffi Pierre Valery Niaba Allico Joseph Djaman Grah Avit Maxwell Beugre 《Food and Nutrition Sciences》 CAS 2024年第5期377-389,共13页
Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposin... Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposing to infections. This study of the physico-chemical and nutritional properties of a soumara-based food broth was carried out with the aim of promoting the consumption of organic broth made from nere seeds (soumara). That is to alleviate certain metabolic diseases, which is a matter of food safety, and also to limit the risk for the health about the consumption of some cooking stocks on the market. Methods: Several natural ingredients such as nere seeds (soumara), ginger, black pepper, parsley and garlic were used to create a nere-based stock. All these ingredients were freeze-dried and the powder obtained was used to make the broth, regarding their physical and chemical properties. Results: The broth had a good protein content of 17.41 ± 0.367 g/100g, a lipid content of 16.80 ± 0.08 g/100g and a fiber content of 8.66 ± 0.04 g/100g. In terms of nutritional values, the broth showed good levels of calcium 184.21 ± 0.09 mg/100g, potassium 50.04 ± 1.45 mg/100g and iron and zinc. In terms of antioxidant activity, the broth also showed good antioxidant activity. Conclusion: Regarding the properties of our food broth, whose composition is based on natural ingredients, could be recommended for consumption and, its properties, could play an important role in preventing and combating certain metabolic diseases. 展开更多
关键词 Food Broth Nere Physico-Chemical Properties NUTRITION Food Safety
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THE KILLING FORMS AND DECOMPOSITION THEOREMS OF LIE SUPERTRIPLE SYSTEMS 被引量:6
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作者 张知学 贾培佩 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期360-370,共11页
In this article, the Killing form of a Lie supertriple system (LSTS) and that of its imbedding Lie superalgebra (LSA) are investigated, and a unique decomposition theorem for a quasiclassical LSTS with trivial cen... In this article, the Killing form of a Lie supertriple system (LSTS) and that of its imbedding Lie superalgebra (LSA) are investigated, and a unique decomposition theorem for a quasiclassical LSTS with trivial center is established by means of the parallel decomposition theorem for a quasiclassical LSA. 展开更多
关键词 Killing form Lie supertriple system quasiclassical
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A Family of Fifth-order Iterative Methods for Solving Nonlinear Equations 被引量:4
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作者 Liu Tian-Bao Cai Hua Li Yong 《Communications in Mathematical Research》 CSCD 2013年第3期255-260,共6页
In this paper, we present and analyze a family of fifth-order iterative methods free from second derivative for solving nonlinear equations. It is established that the family of iterative methods has convergence order... In this paper, we present and analyze a family of fifth-order iterative methods free from second derivative for solving nonlinear equations. It is established that the family of iterative methods has convergence order five. Numerical examples show that the new methods are comparable with the well known existing methods and give better results in many aspects. 展开更多
关键词 Newton's method iterative method nonlinear equation order of convergence
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Generalized Extended tanh-function Method for Traveling Wave Solutions of Nonlinear Physical Equations 被引量:6
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作者 CHANG JING GAO YI-XIAN AND CAI HUA 《Communications in Mathematical Research》 CSCD 2014年第1期60-70,共11页
In this paper, the generalized extended tanh-function method is used for constructing the traveling wave solutions of nonlinear evolution equations. We choose Fisher's equation, the nonlinear schr&#168;odinger equat... In this paper, the generalized extended tanh-function method is used for constructing the traveling wave solutions of nonlinear evolution equations. We choose Fisher's equation, the nonlinear schr&#168;odinger equation to illustrate the validity and ad-vantages of the method. Many new and more general traveling wave solutions are obtained. Furthermore, this method can also be applied to other nonlinear equations in physics. 展开更多
关键词 generalized tanh-function method nonlinear Schrodinger equation Fisher's equation
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Optimization of operation conditions for extracting lithium ions from calcium chloride-type oil field brine 被引量:2
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作者 Hong-jun Yang Qing-hai Li +3 位作者 Bing Li Feng-qin Guo Qing-fen Meng Wu Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第4期290-294,共5页
AI(OH)3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3+/Li+ molar ratio, OH-/Al3+ molar ratio, and contact time between AI... AI(OH)3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3+/Li+ molar ratio, OH-/Al3+ molar ratio, and contact time between AI(OH)3 and the brine, on the yield of lithium ions were investigated. It is found that their optimal values are 35℃, 4.5, 2.6, and 6 h, respectively. In the course of the experiment, the apparent pH value was observed. The results reveal that the apparent pH value has no remarkable influence on the yield of lithium ions. Meanwhile, the effects of the concentrations of calcium ions and magnesium ions in the brine on lithium recovery were studied. The results indicate that cal- cium ions have minor negative influence on the yield of lithium ions under optimal conditions, and magnesium ions slightly influence the yield of lithium ions. 展开更多
关键词 LITHIUM EXTRACTION oil field brine aluminium hydroxide
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Effects of grinding-induced grain boundary and interfaces on electrical transportation and structure phase transition in ZnSe under high pressure 被引量:1
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作者 杨洁 汪沛 +3 位作者 张国召 周晓雪 李静 刘才龙 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期366-370,共5页
Interface and scale effects are the two most important factors which strongly affect the structure and the properties of nano-/micro-crystals under pressure.We conduct an experiment under high pressure in situ alterna... Interface and scale effects are the two most important factors which strongly affect the structure and the properties of nano-/micro-crystals under pressure.We conduct an experiment under high pressure in situ alternating current impedance to elucidate the effects of interface on the structure and electrical transport behavior of two Zn Se samples with different sizes obtained by physical grinding.The results show that(i) two different-sized Zn Se samples undergo the same phase transitions from zinc blend to cinnabar-type phase and then to rock salt phase;(ii) the structural transition pressure of the859-nm Zn Se sample is higher than that of the sample of 478 nm,which indicates the strong scale effect.The pressure induced boundary resistance change is obtained by fitting the impedance spectrum,which shows that the boundary conduction dominates the electrical transport behavior of Zn Se in the whole experimental pressure range.By comparing the impedance spectra of two different-sized Zn Se samples at high pressure,we find that the resistance of the 478-nm Zn Se sample is lower than that of the 859-nm sample,which illustrates that the sample with smaller particle size has more defects which are due to physical grinding. 展开更多
关键词 interface effect IMPEDANCE phase transition high pressure
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Context and Machine Learning Based Trust Management Framework for Internet of Vehicles 被引量:1
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作者 Abdul Rehman Mohd Fadzil Hassan +4 位作者 Yew Kwang Hooi Muhammad Aasim Qureshi Tran Duc Chung Rehan Akbar Sohail Safdar 《Computers, Materials & Continua》 SCIE EI 2021年第9期4125-4142,共18页
Trust is one of the core components of any ad hoc network security system.Trust management(TM)has always been a challenging issue in a vehicular network.One such developing network is the Internet of vehicles(IoV),whi... Trust is one of the core components of any ad hoc network security system.Trust management(TM)has always been a challenging issue in a vehicular network.One such developing network is the Internet of vehicles(IoV),which is expected to be an essential part of smart cities.IoV originated from the merger of Vehicular ad hoc networks(VANET)and the Internet of things(IoT).Security is one of the main barriers in the on-road IoV implementation.Existing security standards are insufficient to meet the extremely dynamic and rapidly changing IoV requirements.Trust plays a vital role in ensuring security,especially during vehicle to vehicle communication.Vehicular networks,having a unique nature among other wireless ad hoc networks,require dedicated efforts to develop trust protocols.Current TM schemes are inflexible and static.Predefined scenarios and limited parameters are the basis for existing TM models that are not suitable for vehicle networks.The vehicular network requires agile and adaptive solutions to ensure security,especially when it comes to critical messages.The vehicle network’s wireless nature increases its attack surface and exposes the network to numerous security threats.Moreover,internet involvement makes it more vulnerable to cyberattacks.The proposed TM framework is based on context-based cognition and machine learning to be best suited to IoV dynamics.Machine learning is the best solution to utilize the big data produced by vehicle sensors.To handle the uncertainty Bayesian machine learning statistical model is used.The proposed framework can adapt scenarios dynamically and infer using the maximum possible parameter available.The results indicated better performance than existing TM methods.Furthermore,for future work,a high-level machine learning model is proposed. 展开更多
关键词 Internet of vehicles(IoV) trust management(TM) vehicular ad hoc network(VANET) machine learning context awareness bayesian learning
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Positive solutions of three-point boundary value problems 被引量:1
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作者 缪烨红 张吉慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第6期817-823,共7页
In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in... In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in resonance cases. The proposed approach is based on the Krasnoselskii's fixed point theorem and the coincidence degree. 展开更多
关键词 three-point boundary value problems positive solution fixed point theorem coincidence degree theorem
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Finite-Difference Lattice Boltzmann Scheme for High-Speed Compressible Flow:Two-Dimensional Case 被引量:1
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作者 GAN Yan-Biao XU Ai-Guo +3 位作者 ZHANG Guang-Cai ZHANG Ping ZHANG Lei LI Ying-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期201-210,共10页
Lattice Boltzmann (LB) modeling of high-speed compressible flows has long been attempted by various authors. One common weakness of most of previous models is the instability problem when the Mach number of the flow... Lattice Boltzmann (LB) modeling of high-speed compressible flows has long been attempted by various authors. One common weakness of most of previous models is the instability problem when the Mach number of the flow is large. In this paper we present a finite-difference LB model, which works for flows with flexible ratios of specific heats and a wide range of Mach number, from 0 to 30 or higher. Besides the discrete-velocity-model by Watari [Physica A 382 (2007) 502], a modified Lax Wendroff finite difference scheme and an artificial viscosity are introduced. The combination of the finite-difference scheme and the adding of artificial viscosity must find a balance of numerical stability versus accuracy. The proposed model is validated by recovering results of some well-known benchmark tests: shock tubes and shock reflections. The new model may be used to track shock waves and/or to study the non-equilibrium procedure in the transition between the regular and Mach reflections of shock waves, etc. 展开更多
关键词 lattice Boltzmann method high-speed compressible flow von Neumann analysis
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Extended tanh-function Method for Solving Traveling Wave Solutions of Nonlinear Kundu Equation 被引量:1
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作者 Cai Hua Guo Ning +2 位作者 Chang Jing Liu Li-huan Wu Xian-na 《Communications in Mathematical Research》 CSCD 2016年第3期281-288,共8页
In this paper, we study the existence of multiple positive periodic solutions for the second order differential equation x′′(t) + p(t)x′(t) + q(t)x(t) = f(t, x(t)).By using Krasnoselskii fixed point... In this paper, we study the existence of multiple positive periodic solutions for the second order differential equation x′′(t) + p(t)x′(t) + q(t)x(t) = f(t, x(t)).By using Krasnoselskii fixed point theorem, we establish some criteria for the existence and multiple positive periodic solutions for this differential equation. 展开更多
关键词 positive periodic solution multiplicity differential equation Krasnoselskii fixed point theorem
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Pressure-Induced Metallization and Electrical Phase Diagram for Polycrystalline CaB_6 under High Pressure and Low Temperature
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作者 杨洁 焦阳 +1 位作者 韩永昊 李晶 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期88-90,共3页
The electrical properties of polycrystaltine CaB6 are revealed by in-situ resistance measurements under high pressure and low temperature. Due to the existence of grain boundaries, polycrystalline CaB6 behaves with se... The electrical properties of polycrystaltine CaB6 are revealed by in-situ resistance measurements under high pressure and low temperature. Due to the existence of grain boundaries, polycrystalline CaB6 behaves with semiconducting transport properties, which is different from the semimetallic CaB6 single crystals. The temperaturedependent resistance measurement results show that before the structural phase transition at 12.3 GPa the high pressure first induces the metallization at 6.5 GPa for CAB6. Moreover, the phase diagram for CaB6 is drawn based on the investigated electric conducting properties and at least three different conducting phases are found even at moderate high pressure and low temperature, indicating that the electric nature of CaB6 is very sensitive to the environment. 展开更多
关键词 for is of Pressure-Induced Metallization and Electrical Phase Diagram for Polycrystalline CaB6 under High Pressure and Low Temperature in high been that
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In situ electrical resistance and activation energy of solid C_(60) under high pressure
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作者 杨洁 刘才龙 高春晓 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期516-519,共4页
The in situ electrical resistance and transport activation energies of solid C60 fullerene have been measured under high pressure up to 25 GPa in the temperature range of 300-423 K by using a designed diamond anvil ce... The in situ electrical resistance and transport activation energies of solid C60 fullerene have been measured under high pressure up to 25 GPa in the temperature range of 300-423 K by using a designed diamond anvil cell. In the experiment, four parts of boron-doped diamond films fabricated on one anvil were used as electrical measurement probes and a W-Ta thin film thermocouple which was integrated on the other diamond anvil was used to measure the temperature. The current results indicate that the measured high-pressure resistances are bigger than those reported before at the same pressure and there is no pressure-independent resistance increase before 8 GPa. From the temperature dependence of the resistivity, the C60 behaviors as a semiconductor and the activation energies of the cubic C60 fullerene are 0,49, 0.43, and 0.36 eV at 13, 15, and 19 GPa, respectively. 展开更多
关键词 high pressure electrical resistance activation energy C60 fullerene
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Transition probabilities and lifetimes of the low-lying levels of Fe XIV
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作者 范建中 汪青敏 +1 位作者 常志伟 董晨钟 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期141-149,共9页
The multi-configuration Dirac-Fock method is employed to calculate the transition energies, probabilities, and oscillator strengths for electric dipole allowed (El) and forbidden (M1, E2, M2) lines for the 3s^23p,... The multi-configuration Dirac-Fock method is employed to calculate the transition energies, probabilities, and oscillator strengths for electric dipole allowed (El) and forbidden (M1, E2, M2) lines for the 3s^23p, 3s3p^2, 3s^23d, 3p^3, and 3s3p3d configurations of Fe XIV. The lifetimes of all 40 levels of these low-lying configurations are also derived. The valence valence and core-valence correlation effects are accounted for in a systematic way. Breit interactions and quantum electrodynamics (QED) effects are estimated in subsequent relativistic configuration interaction (CI) calculations. The present results are in good agreement with other available theoretical and experimental values, and therefore can be used for the further astrophysical investigations. 展开更多
关键词 transition probability LIFETIME Fe XIV
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Energy-Crossing and Its Effect on Lifetime of the 4s24p2P3/2 Level for Highly Charged Ga-Like Ions
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作者 FAN Jian-Zhong ZHANG Deng-Hong +2 位作者 CHANG Zhi-Wei SHI Ying-Long DONG Chen-Zhong 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第7期75-79,共5页
The multi-configuration Dirac-Fock method is employed to calculate the energy levels and transition probabilities for the electric dipole allowed (El) and forbidden (M1,E2) lines for the 4s^(2) 4p,4s4p^(2) and 4s^(2) ... The multi-configuration Dirac-Fock method is employed to calculate the energy levels and transition probabilities for the electric dipole allowed (El) and forbidden (M1,E2) lines for the 4s^(2) 4p,4s4p^(2) and 4s^(2) 4d configurations of highly charged Ga-like ions from Z =68-95.The lifetimes of the 4s^(2) 4p^(2) P3/2 level of the ground configuration are also derived.Based on our calculations,it is found that the energy level of the 4s2 4p 2P3/2 is higher than that of the 4s4p24P1/2 for the high-Z Ga-like ions with Z ≥ 74,so as to generate an energy crossing at Z =74.The effect of the energy crossing is important to the calculation of the 4s^(2) 4p^(2) P3/2 level lifetime for Ga-like ions with Z≥ 74. 展开更多
关键词 CONFIGURATION allowed HIGHLY
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The Sufficient and Necessary Condition of Lagrange Stability of Quasi-periodic Pendulum Type Equations
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作者 CONG FU-ZHONG LIANG XIN HAN YUE-CAI 《Communications in Mathematical Research》 CSCD 2010年第1期76-84,共9页
The quasi-periodic pendulum type equations are considered. A sufficient and necessary condition of Lagrange stability for this kind of equations is obtained. The result obtained answers a problem proposed by Moser und... The quasi-periodic pendulum type equations are considered. A sufficient and necessary condition of Lagrange stability for this kind of equations is obtained. The result obtained answers a problem proposed by Moser under the quasi-periodic case. 展开更多
关键词 Lagrange stability pendulum type equation KAM theorem
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Complex Behaviors of a Simple Traffic Model
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作者 GAO Xing-Ru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期952-960,共9页
In this paper, we propose a modified traffic model in which a single car moves through a sequence of traffic lights controlled by a step function instead of a sine function. In contrast to the previous work [Phys. Rev... In this paper, we propose a modified traffic model in which a single car moves through a sequence of traffic lights controlled by a step function instead of a sine function. In contrast to the previous work [Phys. Rev. E 70 (2004) 016107], we have investigated in detail the dependence of the behavior on four parameters, ω,α,η and α1, and given three kinds of bifurcation diagrams, which show three kinds of complex behaviors. We have found that in this model there are chaotic and complex periodic motions, as well as special singularities. We have also analyzed the characteristic of the complex period motion and the essential feature of the singularity. 展开更多
关键词 traffic model complex behavior CHAOS bifurcation diagram SINGULARITY
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Periodic Solutions for the Higher Order Differential Equations with Multiple Delays
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作者 梁心 从福仲 《Northeastern Mathematical Journal》 CSCD 2008年第6期558-564,共7页
By Fourier analysis techniques and Schauder fixed point theorem, we study the existence of periodic solutions for a class of even order differential equations with multiple delays. The result obtained is a generalizat... By Fourier analysis techniques and Schauder fixed point theorem, we study the existence of periodic solutions for a class of even order differential equations with multiple delays. The result obtained is a generalization of the results developed by W. Layton to the case of multiple delays. 展开更多
关键词 (2k)th-order differential equation multiple delay periodic solution Schauder fixed point theorem
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PainlevéAnalysis of Higher Order Nonlinear Evolution Equations with Variable Coefficients
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作者 Wang Yuan 《Chinese Quarterly Journal of Mathematics》 2021年第2期196-203,共8页
There is a close relationship between the Painlevéintegrability and other integrability of nonlinear evolution equation.By using the Weiss-Tabor-Carnevale(WTC)method and the symbolic computation of Maple,the Pain... There is a close relationship between the Painlevéintegrability and other integrability of nonlinear evolution equation.By using the Weiss-Tabor-Carnevale(WTC)method and the symbolic computation of Maple,the Painlevétest is used for the higher order generalized non-autonomous equation and the third order Korteweg-de Vries equation with variable coefficients.Finally the Painlevéintegrability condition of this equation is gotten. 展开更多
关键词 Higher order generalized non-autonomous equation Third order Korteweg-de Vries equation with variable coefficients Painlevéanalysis method
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Ising Model on an Infinite Ladder Lattice
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作者 GAO Xing-Ru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期553-562,共10页
In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the... In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the ladder lattice is infinite, while its width is finite. We investigate the phase transition and dynamic behavior of Ising model on this quasi-one-dimessional system. We use the generalized transfer matrix method to investigate the phase transition of the system. It is found that there is no nonzero temperature phase transition in this system. At the same time, we are interested in Glauber dynamics. Based on that, we obtain the time evolution of the local spin magnetization by exactly solving a set of master equations. 展开更多
关键词 Ising model general transfer matrix phase transition Glauber dynamics critical slow down
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