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Normalized Ground State Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan ZHAO Hui-yan XU Li-ping 《Chinese Quarterly Journal of Mathematics》 2024年第3期250-261,共12页
In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/... In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/N Under appropriate hypotheses on V(x),we prove that the above Choquard equation has a normalized ground state solution by utilizing variational methods. 展开更多
关键词 Choquard equation Nonconstant potential function Normalized ground state solutions Variational methods
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New Approach for Solving Master Equations in Quantum Optics and Quantum Statistics by Virtue of Thermo-Entangled State Representation 被引量:11
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作者 FAN Hong-Yi HU Li-Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期729-742,共14页
By introducing a fictitious mode to be a counterpart mode of the system mode under review we introduce the entangled state representation (η|, which can arrange master equations of density operators p(t) in quant... By introducing a fictitious mode to be a counterpart mode of the system mode under review we introduce the entangled state representation (η|, which can arrange master equations of density operators p(t) in quantum statistics as state-vector evolution equations due to the elegant properties of (η|. In this way many master equations (respectively describing damping oscillator, laser, phase sensitive, and phase diffusion processes with different initial density operators) can be concisely solved. Specially, for a damping process characteristic of the decay constant k we find that the matrix element of p(t) at time t in 〈η| representation is proportional to that of the initial po in the decayed entangled state (ηe^-kt| representation, accompanying with a Gaussian damping factor. Thus we have a new insight about the nature of the dissipative process. We also set up the so-called thermo-entangled state representation of density operators, ρ = f(d^2η/π)(η|ρ〉D(η), which is different from all the previous known representations. 展开更多
关键词 master equation fictitious mode thermo-entangled state representation damping oscillator and laser phase sensitive and phase diffusion processes
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Ground states for asymptotically periodic quasilinear Schrdinger equations with critical growth
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作者 张慧 张福保 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期352-354,共3页
For a class of asymptotically periodic quasilinear Schr?dinger equations with critical growth the existence of ground states is proved.First applying a change of variables the quasilinear Schr?dinger equations are r... For a class of asymptotically periodic quasilinear Schr?dinger equations with critical growth the existence of ground states is proved.First applying a change of variables the quasilinear Schr?dinger equations are reduced to semilinear Schr?dinger equations in which the corresponding functional is well defined in H1 RN .Moreover there is a one-to-one correspondence between ground states of the semilinear Schr?dinger equations and the quasilinear Schr?dinger equations.Then the mountain-pass theorem is used to find nontrivial solutions for the semilinear Schr?dinger equations. Finally under certain monotonicity conditions using the Nehari manifold method and the concentration compactness principle the nontrivial solutions are found to be exactly the same as the ground states of the semilinear Schr?dinger equations. 展开更多
关键词 quasilinear Schrodinger equation variationalmethod ground state critical growth
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EQUATIONS OF STATE FOR HARD-SPHERE CHAIN FLUIDS AND SQUARE-WELL CHAIN FLUIDS 被引量:1
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作者 刘洪来 戎宗明 胡英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1996年第2期4-12,共9页
Based on the statistical theory for chemical association,equations of state for hard-spherechain fluids(HSCFs)and square-well chain fluids(SWCFs)can be derived through the n-particlecavity correlation function(CCF)of ... Based on the statistical theory for chemical association,equations of state for hard-spherechain fluids(HSCFs)and square-well chain fluids(SWCFs)can be derived through the n-particlecavity correlation function(CCF)of the corresponding reference system,where n is the chain lengthor the number of segments of a chain molecule.The reference system is a fluid composed of only cor-responding monomers.In this work,the n-particle CCF is approximated by a product of effectivetwo-particle CCFs which accounts for correlations in nearest-neighbour and next-to-nearest-neighboursegment pairs.The CCFs for SWCFs may be expressed by a product of the corresponding functionfor HSCFs and a perturbation term originated from the square-well attractive potential.All these ef-fective two-particle CCFs and perturbation terms are density dependent.The dependence is determinedmainly by using computer-simulation results.The obtained equations can excellently describecompressibility factors and second Virial coefficients for 展开更多
关键词 equation of state POLYMER solution POLYMER blend compressibility factor second VIRIAL coefficient statistical theory chemical association
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Calculation of Viscosities of Liquid Mixtures Using Eyring's Theory in Combination with Cubic Equations of State 被引量:1
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作者 计伟荣 D.A.Lempe 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6期770-779,共10页
Cubic equations of state (EOS) have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in compar... Cubic equations of state (EOS) have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in comparison with the van Laar and the Redlich-Kister-type mixing rule. The EOS method gives an accurate correlation of liquid viscosities with an overall average deviation less than 1% for 67 binary systems including aqueous solutions. It is also successful in extrapolating viscosity data over a certain temperature range using parameters obtained from the isotherm at a given temperature and in predicting viscosities of ternary solutions from binary parameters for either polar or associated systems. 展开更多
关键词 viscosity equation of state MIXING rule ABSOLUTE rate THEORY
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Inference of General Mass Action-Based State Equations for Oscillatory Biochemical Reaction Systems Using <i>k</i>-Step Genetic Programming 被引量:1
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作者 Tatsuya Sekiguchi Hiroyuki Hamada Masahiro Okamoto 《Applied Mathematics》 2019年第8期627-645,共19页
Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP... Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP), is useful for its high heuristic ability as a search method for obtaining suitable solutions expressed as tree structures. However, because GP determines the values of parameters such as coefficients by random values, it is difficult to apply in the inference of state equations that describe oscillatory biochemical reaction systems with high nonlinearity. Accordingly, in this study, we propose a new GP procedure called “k-step GP” intended for inferring the state equations of oscillatory biochemical reaction systems. The k-step GP procedure consists of two algorithms: 1) Parameter optimization using the modified Powell method—after genetic operations such as crossover and mutation, the values of parameters such as coefficients are optimized by applying the modified Powell method with secondary convergence. 2) GP using divided learning data—to improve the inference efficiency, imposes perturbations through the addition of learning data at various intervals and adaptations to these changes result in state equations with higher fitness. We are confident that k-step GP is an algorithm that is particularly well suited to inferring state equations for oscillatory biochemical reaction systems and contributes to solving inverse problems in systems biology. 展开更多
关键词 SYSTEMS Biology Genetic Programming Inverse Problems OSCILLATORY BIOCHEMICAL Reaction SYSTEMS GMA-Based state equations
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An insight into the role of the association equations of states in gas hydrate modeling:a review 被引量:1
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作者 Feridun Esmaeilzadeh Nazanin Hamedi +1 位作者 Dornaz Karimipourfard Ali Rasoolzadeh 《Petroleum Science》 SCIE CAS CSCD 2020年第5期1432-1450,共19页
Encouraged by the wide spectrum of novel applications of gas hydrates,e.g.,energy recovery,gas separation,gas storage,gas transportation,water desalination,and hydrogen hydrate as a green energy resource,as well as CO... Encouraged by the wide spectrum of novel applications of gas hydrates,e.g.,energy recovery,gas separation,gas storage,gas transportation,water desalination,and hydrogen hydrate as a green energy resource,as well as CO2 capturing,many scientists have focused their attention on investigating this important phenomenon.Of course,from an engineering viewpoint,the mathematical modeling of gas hydrates is of paramount importance,as anticipation of gas hydrate stability conditions is effective in the design and control of industrial processes.Overall,the thermodynamic modeling of gas hydrate can be tackled as an equilibration of three phases,i.e.,liquid,gas,and solid hydrate.The inseparable component in all hydrate systems,water,is highly polar and non-ideal,necessitating the use of more advanced equation of states(EoSs) that take into account more intermolecular forces for thermodynamic modeling of these systems.Motivated by the ever-increasing number of publications on this topic,this study aims to review the application of associating EoSs for the thermodynamic modeling of gas hydrates.Three most important hydrate-based models available in the literature including the van der Waals-Platteeuw(vdW-P) model,Chen-Guo model,and Klauda-Sandler model coupled with and SAFT EoSs were investigated and compared with cubic EoSs.It was concluded that the CPA and SAFT EoSs gave very accurate results for hydrate systems as they take into account the association interactions,which are very crucial in gas hydrate systems in which water,methanol,glycols,and other types of associating compounds are available.Moreover,it was concluded that the CPA EoS is easier to use than the SAFT-type EoSs and our suggestion for the gas hydrate systems is the CPA EoS. 展开更多
关键词 HYDRATE Mathematical modeling Equation of state SAFT CPA Association EoS
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NODAL BOUND STATES WITH CLUSTERED SPIKES FOR NONLINEAR SCHRDINGER EQUATIONS 被引量:1
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作者 代晋军 何其涵 李必文 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1892-1906,共15页
We consider the following nonlinear Schroodinger equations -ε^2△u + u = Q(x)|u|^p-2u in R^N, u ∈ H^1(R^N),where ε is a small positive parameter, N ≥ 2, 2 〈 p 〈 ∞ for N = 2 and 2 〈 p 〈2N/N-2 for N ≥ 3... We consider the following nonlinear Schroodinger equations -ε^2△u + u = Q(x)|u|^p-2u in R^N, u ∈ H^1(R^N),where ε is a small positive parameter, N ≥ 2, 2 〈 p 〈 ∞ for N = 2 and 2 〈 p 〈2N/N-2 for N ≥ 3. We prove that this problem has sign-changing(nodal) semi-classical bound states with clustered spikes for sufficiently small ε under some additional conditions on Q(x).Moreover, the number of this type of solutions will go to infinity as ε→ 0^+. 展开更多
关键词 nodal bound states Lyapunov-Schmidt reduction Schrdinger equations
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THE EXISTENCE AND CONCENTRATION OF GROUND STATE SIGN-CHANGING SOLUTIONS FOR KIRCHHOFF-TYPE EQUATIONS WITH A STEEP POTENTIAL WELL 被引量:1
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作者 吴梦慧 唐春雷 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1781-1799,共19页
In this paper,we consider the nonlinear Kirchhoff type equation with a steep potential well−(a+b∫_(R)^(3)|∇u|^(2 )dx)Δu+λV(x)u=f(u)in R^(3),where a,b>0 are constants,λ is a positive parameter,V∈C(R3,R)is a ste... In this paper,we consider the nonlinear Kirchhoff type equation with a steep potential well−(a+b∫_(R)^(3)|∇u|^(2 )dx)Δu+λV(x)u=f(u)in R^(3),where a,b>0 are constants,λ is a positive parameter,V∈C(R3,R)is a steep potential well and the nonlinearity f∈C(R,R)satisfies certain assumptions.By applying a signchanging Nehari manifold combined with the method of constructing a sign-changing(PS)C sequence,we obtain the existence of ground state sign-changing solutions with precisely two nodal domains when λ is large enough,and find that its energy is strictly larger than twice that of the ground state solutions.In addition,we also prove the concentration of ground state sign-changing solutions. 展开更多
关键词 Kirchhoff-type equation ground state sign-changing solutions steep potential well
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CONTINUOUS TIME MIXED STATE BRANCHING PROCESSES AND STOCHASTIC EQUATIONS 被引量:1
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作者 Shukai CHEN Zenghu LI 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1445-1473,共29页
A continuous time and mixed state branching process is constructed by a scaling limit theorem of two-type Galton-Watson processes.The process can also be obtained by the pathwise unique solution to a stochastic equati... A continuous time and mixed state branching process is constructed by a scaling limit theorem of two-type Galton-Watson processes.The process can also be obtained by the pathwise unique solution to a stochastic equation system.From the stochastic equation system we derive the distribution of local jumps and give the exponential ergodicity in Wasserstein-type distances of the transition semigroup.Meanwhile,we study immigration structures associated with the process and prove the existence of the stationary distribution of the process with immigration. 展开更多
关键词 mixed state branching process weak convergence stochastic equation system Wasserstein-type distance stationary distribution
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A NEW APPROACH TO THE EQUATIONS FOR THE STEADY STATE CURRENTS AT MICROELECTRODES:EC'PROCESSES(SECOND ORDER REACTION) 被引量:1
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作者 Qian Kun ZHUANG Hong Yuan CHEN Department of Chemistry,Nanjing University,210008,Nanjing 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期723-726,共4页
With a new approach,the general current expressions of two typical second order catalytic reactions at microelectrodes are obtained.This allows the study of fast chemical reactions and systems where the reactants are ... With a new approach,the general current expressions of two typical second order catalytic reactions at microelectrodes are obtained.This allows the study of fast chemical reactions and systems where the reactants are present in similar concentrations. 展开更多
关键词 EC A NEW APPROACH TO THE equations FOR THE STEADY state CURRENTS AT MICROELECTRODES SECOND ORDER REACTION AT
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Calculation of Viscosities of Liquid Mixtures Using Eyring’s Theory in Combination with Cubic Equations of State
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作者 计伟荣 D. A. Lempe 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6X期770-779,共10页
Cubic equations of state EOS have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in com- par... Cubic equations of state EOS have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in com- parison with the van Laar and the Redlich-Kister-type mixing rule. The EOS method gives an accurate correlation of liquid viscosities with an overall average deviation less than 1% for 67 binary systems including aqueous solu- tions. It is also successful in extrapolating viscosity data over a certain temperature range using parameters obtained from the isotherm at a given temperature and in predicting viscosities of ternary solutions from binary parameters for either polar or associated systems. 展开更多
关键词 VISCOSITY equation of state MIXING RULE ABSOLUTE rate THEORY
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PHASE EQUILIBRIUM OF COMPLEX MIXTURES WITH EQUATIONS OF STATE: AN UPDATE5
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作者 Stanley I.Sandler Hasan orbey 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1995年第1期42-53,共12页
Here we review a new class of mixing rules (hat have extended range of mixtures and conditions that can now be described by equation of state models. One characteristic of these mixing rules is that they simultaneousl... Here we review a new class of mixing rules (hat have extended range of mixtures and conditions that can now be described by equation of state models. One characteristic of these mixing rules is that they simultaneously satisfy the boundary conditions of producing a second virial coefficient that is quadratic in mole fraction, and a free energy of mixing like that of an activity coefficient model at high density, though the mixing rule is itself independent of density. We show that using this mixing rule, various asymmetric, highly nonideal mixtures can be accurately described. One serendipitous result is that the parameters in this mixing rule model are almost independent of temperature, which allows accurate extrapolations of phase behavior to be made over large ranges of temperature and pressure. 展开更多
关键词 equations of state MIXING RULES phase EQUILIBRIUM complex MIXTURES
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Evaluation of attraction terms in equations of state on the prediction of solubility of some biomolecules in supercritical carbon dioxide
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作者 Mohammad Reza Bozorgmehr Mohammad Reza Housaindokht 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期501-505,共5页
In the present work, effect of the attraction terms of four recently modified Peng-Robinson (MPR) equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The... In the present work, effect of the attraction terms of four recently modified Peng-Robinson (MPR) equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The attraction terms of two of these equations are linear relative to the acentric factor and for the other two are exponential. It is found that the later show less deviation. Also interaction parameters for the studied systems are obtained and the percentage of average absolute relative deviation (%AARD) in each calculation is displayed. 展开更多
关键词 Equation of state SOLUBILITY Supercritical carbon dioxide Biomolecules
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New insight into prediction of phase behavior of natural gas hydrate by different cubic equations of state coupled with various mixing rules
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作者 Amir Hossein Saeedi Dehaghani 《Petroleum Science》 SCIE CAS CSCD 2017年第4期780-790,共11页
Progress in hydrate thermodynamic study necessitates robust and fast models to be incorporated in reservoir simulation softwares. However, numerous models presented in the literature makes selection of the best,proper... Progress in hydrate thermodynamic study necessitates robust and fast models to be incorporated in reservoir simulation softwares. However, numerous models presented in the literature makes selection of the best,proper predictive model a cumbersome task. It is of industrial interest to make use of cubic equations of state(EOS) for modeling hydrate equilibria. In this regard, this study focuses on evaluation of three common EOSs including Peng–Robinson, Soave–Redlich–Kwong and Valderrama–Patel–Teja coupled with van der Waals and Platteeuw theory to predict hydrate P–T equilibrium of a real natural gas sample. Each EOS was accompanied with three mixing rules, including van der Waals(vd W),Avlonitis non-density dependent(ANDD) and general nonquadratic(GNQ). The prediction of cubic EOSs was in sufficient agreement with experimental data and with overall AARD% of less than unity. In addition, PR plus ANDD proved to be the most accurate model in this study for prediction of hydrate equilibria with AARD% of 0.166.It was observed that the accuracy of cubic EOSs studied in this paper depends on mixing rule coupled with them,especially at high-pressure conditions. Lastly, the present study does not include any adjustable parameter to be correlated with hydrate phase equilibrium data. 展开更多
关键词 Gas Hydrate Cubic equation of state Mixing rule Thermodynamic modeling
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ON A REGULARIZATION OF INDEX 2 DIFFERENTIAL-ALGEBRAIC EQUATIONS WITH PROPERLY STATED LEADING TERM
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作者 刘红 宋永忠 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期383-398,共16页
In this article, linear regular index 2 DAEs A(t)[D(t)x(t)]' + B(t)x(t) = q(t) are considered. Using a decoupling technique, initial condition and boundary condition are properly formulated. Regular inde... In this article, linear regular index 2 DAEs A(t)[D(t)x(t)]' + B(t)x(t) = q(t) are considered. Using a decoupling technique, initial condition and boundary condition are properly formulated. Regular index 1 DAEs are obtained by a regularization method. We study the behavior of the solution of the regularization system via asymptotic expansions. The error analysis between the solutions of the DAEs and its regularization system is given. 展开更多
关键词 Differential-algebraic equations (DAEs) properly stated leading term in-dex REGULARIZATION
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New approach for analysing master equations of generalized phase diffusion models in the entangled state representation
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作者 徐兴磊 李洪奇 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期918-921,共4页
By virtue of the well-behaved properties of the bipartite entangled states representation, this paper analyse and solves some master equations for generalized phase diffusion models, which seems concise and effective.... By virtue of the well-behaved properties of the bipartite entangled states representation, this paper analyse and solves some master equations for generalized phase diffusion models, which seems concise and effective. This method can also be applied to solve other master equations. 展开更多
关键词 generalized phase diffusion entangled state representation master equations
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Solution of the HJI equations for nonlinear H_∞ control design by state-dependent Riccati equations approach 被引量:1
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作者 Xueyan Zhao Feiqi Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期654-660,共7页
The relationship between the technique by state- dependent Riccati equations (SDRE) and Hamilton-Jacobi-lsaacs (HJI) equations for nonlinear H∞ control design is investigated. By establishing the Lyapunov matrix ... The relationship between the technique by state- dependent Riccati equations (SDRE) and Hamilton-Jacobi-lsaacs (HJI) equations for nonlinear H∞ control design is investigated. By establishing the Lyapunov matrix equations for partial derivates of the solution of the SDREs and introducing symmetry measure for some related matrices, a method is proposed for examining whether the SDRE method admits a global optimal control equiva- lent to that solved by the HJI equation method. Two examples with simulation are given to illustrate the method is effective. 展开更多
关键词 nonlinear system robust control Hamilton-Jacobi-Isaacs (HJI) equation state-dependent Riccati equation (SDRE) global stabilization optimal control.
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Generalization of vdW Type of Equations of State
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作者 云志 史美仁 时钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第1期89-91,共3页
The importance of equations of state (EOS) has brought about the proliferation of hundreds of EOS. Nearly all prevailing cubic EOS could be regarded as the results of reforming the original vdW EOS. However, the accur... The importance of equations of state (EOS) has brought about the proliferation of hundreds of EOS. Nearly all prevailing cubic EOS could be regarded as the results of reforming the original vdW EOS. However, the accuracy of the vdW EOS is so low. In view of this, a new general equation is proposed that could be used to value or compare vdW type of EOS, and consequently develop a better vdW type of EOS. 展开更多
关键词 equation of state volume function GENERALIZATION
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Non-formation of vacuum states for Navier-Stokes equations with density-dependent viscosity
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作者 ZHANG Ting FANG Dao-yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1681-1690,共10页
We consider the Cauchy problem, free boundary problem and piston problem for one-dimensional compressible Navier-Stokes equations with density-dependent viscosity. Using the reduction to absurdity method, we prove tha... We consider the Cauchy problem, free boundary problem and piston problem for one-dimensional compressible Navier-Stokes equations with density-dependent viscosity. Using the reduction to absurdity method, we prove that the weak solutions to these systems do not exhibit vacuum states, provided that no vacuum states are present initially. The essential re- quirements on the solutions are that the mass and energy of the fluid are locally integrable at each time, and the Lloc1-norm of the velocity gradient is locally integrable in time. 展开更多
关键词 Compressible Navier-Stokes equations Vacuum states Density-dependent viscosity
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