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71.
程文成  李巍 《经济数学》2020,37(2):66-72
在跨国闭环供应链中考虑碳关税、碳配额和碳税三种政策的影响,分别建立了出口国制造商(OEM)再制造模型和OEM授权进口国零售商进行再制造模型,得到不同模型中OEM和零售商的最优价格、最优销售量、最优利润,进一步分析了产品碳排放总量是否超过配额的不同情形下新产品碳排放量对新产品和再制造品价格、销售量的影响以及其中碳关税和碳税发挥的作用.结果表明,在配额限制下,存在碳关税、碳税以及两种政策共同约束的取值区间,当税率水平在不同区间时,新产品碳排放量对两种产品的价格、销售量有不同的影响.  相似文献   
72.
We study the global stability of a multistrain SIS model with superinfection and patch structure. We establish an iterative procedure to obtain a sequence of threshold parameters. By a repeated application of a result by Takeuchi et al. [Nonlinear Anal Real World Appl. 2006;7:235–247], we show that these parameters completely determine the global dynamics of the system: for any number of patches and strains with different infectivities, any subset of the strains can stably coexist depending on the particular choice of the parameters.  相似文献   
73.
The quantum thermalization of the Jaynes–Cummings (JC) model in both equilibrium and non-equilibrium open-system cases is studied, in which the two subsystems, a two-level system and a single-mode bosonic field, are in contact with either two individual heat baths or a common heat bath. It is found that in the individual heat-bath case, the JC model can only be thermalized when either the two heat baths have the same temperature or the coupling of the JC system to one of the two baths is turned off. In the common heat-bath case, the JC system can be thermalized irrespective of the bath temperature and the system–bath coupling strengths. The thermal entanglement in this system is also studied. A counterintuitive phenomenon of vanishing thermal entanglement in the JC system is found and proved.  相似文献   
74.
In this paper, we develop and analyze a malaria model with seasonality of mosquito life-history traits: periodic-mosquitoes per capita birth rate, -mosquitoes death rate, -probability of mosquito to human disease transmission, -probability of human to mosquito disease transmission, and -mosquitoes biting rate. All these parameters are assumed to be time dependent leading to a nonautonomous differential equation system. We provide a global analysis of the model depending on two threshold parameters and (with ). When , then the disease-free stationary state is locally asymptotically stable. In the presence of the human disease-induced mortality, the global stability of the disease-free stationary state is guarantied when . On the contrary, if , the disease persists in the host population in the long term and the model admits at least one positive periodic solution. Moreover, by a numerical simulation, we show that a sub-critical (backward) bifurcation is possible at . Finally, the simulation results are in accordance with the seasonal variation of the reported cases of a malaria-epidemic region in Mpumalanga province in South Africa.  相似文献   
75.
This article studies a class of nonlocal stochastic differential equations driven by G-Brownian motion (G-NSDEs for short). We show the existence and uniqueness results of solutions by means of fixed point theorem. In addition, exponential estimation of (1) has been discussed. Furthermore, we present global solution to Equation (1) with the help of G-Lyapunov functional and ψ-type function.  相似文献   
76.
This paper studies an (n+4)-dimensional nonlinear virus dynamics model that characterizes the interactions of the viruses, susceptible host cells, n-stages of infected cells, B cells and cytotoxic T lymphocyte (CTL) cells. Both viral and cellular infections have been incorporated into the model. The infected-susceptible and virus-susceptible infection rates as well as the generation and removal rates of all compartments are described by general nonlinear functions. Five threshold parameters are computed, which insure the existence of the equilibria of the model under consideration. A set of conditions on the general functions has been established, which is sufficient to investigate the global dynamics of the model. The global asymptotic stability of all equilibria is proven by utilizing Lyapunov function and LaSalle's invariance principle. The theoretical results are illustrated by numerical simulations of the model with specific forms of the general functions.  相似文献   
77.
78.
In this paper, we study the global (in time) existence of small data solutions to the Cauchy problem for the semilinear wave equation with friction, viscoelastic damping, and a power nonlinearity. We are interested in the connection between regularity assumptions for the data and the admissible range of exponents p in the power nonlinearity.  相似文献   
79.
The paper is devoted to local and global solvability in locally uniform spaces and to the existence of a global attractor for a parabolic problem containing fractional power of the minus Laplace operator. Several useful technical tools and estimates are also collected in this paper.  相似文献   
80.
传统彩虹测量技术标定复杂、精度可重复性差且难以适应密闭空间。一种基于多彩虹谱线自标定方法,可省去原有的标定系统装置,将标定过程内化于对彩虹信号的处理,以水为例的测量偏差仅为0.13%。将该技术应用于混合喷雾液滴组分浓度测量中,探究并优化了参与混合的两种液体组分的方案。实验采用60%乙醇-水混合喷雾,原位测量了混合喷雾场多点组分浓度,测量结果差别可以控制在0.5%以内,表明该方法技术在相关领域的应用潜力。  相似文献   
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