Asymptotic behavior of large solution to elliptic equation of Bieberbach–Rademacher type with convection terms

We analyze the asymptotic behavior of solutions to nonlinear elliptic equation Δu±|u|^q=b(x)f(u) in Ω, subject to the singular boundary condition u(x)=∞ as , where Ω is a smooth bounded domain in R^N, for some , and . Our approach employs Karamata regular variation theory combined with the method of lower and supper solution.     

Optimal harvesting for periodic age-dependent population dynamics with logistic term

We prove an asymptotic behavior result for an age-dependent population dynamics with logistic term and periodic vital rates. We investigate next an optimal harvesting problem related to a periodic age-structured model with logistic term. Existence of an optimal control and necessary optimality conditions are established. A conceptual algorithm to approximate the optimal pair is derived and some numerical experiments are presented.     

Modeling and simulation of a gas distribution pipeline network

This research study focuses on the modeling and simulation of a gas distribution pipeline network with a special emphasis on gas ducts. Gas ducts are the most important components of such kind of systems since they define the major dynamic characteristics. Isothermal, unidirectional flow is usually assumed when modeling the gas flow through a gas duct. This paper presents two simplified models derived from the set of partial differential equations governing the dynamics of the process. These models include the inclination term, neglected in most related papers. Moreover, two numerical schemes are presented for the integration of such models. Also, it is shown how the pressure drop along the pipe has a strong dependency with the inclination term. To solve the system dynamics through the proposed numerical schemes a based MATLAB-Simulink library was built. With this library it is possible to simulate the behavior of a gas distribution network from the individual simulation of each component. Finally, the library is tested through three application examples, and results are compared with the existing ones in the literature.     

浙江省自然保护区常绿阔叶林优势种群的生态位特征

以样方法对不同资源位群落进行调查,通过计算群落的生态位宽度、生态位相似性比例和生态位重叠值,分析浙江省7个自然保护区18个常绿阔叶林的12个优势种的生态位特征,探讨了各优势种群在次生林和原生林中生态位宽度、相似性和重叠的差异,比较了乔木树种与小乔木或灌木生态位宽度的差异.结果表明：(1)浙江省各保护区的常绿阔叶林多以木荷或甜槠为建群种或共优种,具有典型的中亚热带常绿阔叶林生态位相似性比例高的特点,且生态位重叠程度较低;(2)次生林中各种群的生态位宽度明显高于原生林,原生林的生态位相似性比例和生态位重叠均高于次生林;(3)常绿阔叶林中小乔木或灌木的生态位宽度趋中,次生林的情况基本相似,而原生林中小乔木或灌木树种的生态位宽度在整个生态位宽度列表中位置提前了.      

公平关切下零售商主导闭环供应链的定价策略

研究公平关切行为偏好对闭环供应链定价策略的影响,分别基于成员公平中性、制造商公平关切以及两者同时公平关切三种情况,构建了相应的利润决策模型。通过对均衡结果的分析比较发现:随着供应链成员企业公平关切程度的增大,新产品的批发价及零售价均会随之增加,但新产品销量及废旧产品回收率却随之减少;其次,制造商公平关切程度的增加始终促进自身利润及效用的增加,但却对主导零售商及闭环供应链系统的总利润造成了不利影响。     

Monotone methods and stability results for nonlocal reaction-diffusion equations with time delay

In this paper, we study the applications of the monotone iteration method for investigating the existence and stability of solutions to nonlocal reaction-diffusion equations with time delay. We emphasize the importance of the idea of monotone iteration schemes for investigating the stability of solutions to such equations. We show that every steady state of such equations obtained by using the monotone iteration method is priori stable and all stable steady states can be obtained by using such method. Finally, we apply our main results to three population models.     

Existence and global stability of almost automorphic solutions for shunting inhibitory cellular neural networks with time-varying delays in leakage terms on time scales

In this paper, shunting inhibitory cellular neural networks(SICNNs) with time-varying delays in leakage terms on time scales are investigated. With the aid of the existence of the exponential dichotomy of linear dynamic equations on time scales, fixed point theorem and the theory of calculus on time scales, we establish some sufficient conditions to ensure the existence and exponential stability of almost automorphic solutions for the model. An example with its numerical simulations is given to illustrate the feasibility and effectiveness of the theoretical findings.     

五次NLS方程全离散谱格式的大时间性态

Nonlinear Schroedinger equation arises in many physical problems. There are many works in which properties of the solution are studied. In this paper we use fully discrete Fourier spectral method to get an approximation solution of nonlinear weakly dissipative Schroedinger equation with quintic term. We give a large-time error estimate and obtain the existence of the approximate attractor A N^k.     

数据矩阵条件指数的局部影响分析

以广义影响函数和广义Cook统计量为工具,考察对数据矩阵同时进行微小扰动在条件指数上产生的局部影响,导出了寻找条件指数最大影响方向的计算公式,并用一个实例说明该方法的应用．