POSITIVENESS THEOREMS OF SOLUTIONS FOR SEVERAL DIFFERENTIAL INEQUALITIES AND THEIR APPLICATIONS

IIntroductlonMny mathematical models rom physics,chemistry biology,economics etc．are so calledre。ilo。dlAslon srstems．ljtlstence of tr。ling w。front solutions(TWFSs)for these sys－terns rdects Int。aCtions among components ofsystems and TTSs have their own physicalme。lug(see【l])．The upper。d ic。r solutions method Is often used to pro、the。lstenceofTWFSs for certain concrete models．Difficulties consist ofconstrudlug concrete upper andlower solutions and provingtheboundedness and…     

A bound for Wilson''''s general theorem

Given any set K of positive integers and positive integer λ, let c(K,λ) denote the smallest integer such that v∈B(K,λ) for every integer v≥c(K,λ) that satisfies the congruences λv(v-1)≡0 (mod β(K) and λ(v-1)≡0 (mod α(K)). Let K0 be an equivalent set of K, k and k* be the smallest and the largest integers in K0. We prove that c(K,λ)≤exp exp{Q0}Qo=max{2(2p(ko)2-k2kk)p(ko)4,(Kk242y-k-2)(y2)}, whereand y=k*+k(k-1)+1.     

非线性KdV-mKdV方程的新的复合函数解

利用孤立子方程KdV-mKdV的朗斯基解的形式和结构,我们提出了朗斯基形式展开法,运用这一方法获得了KdV-mKdV方程的丰富的新的复合函数解,并且朗斯基行列式中的元素不满足任何线性偏微分方程组.所得到的复合函数解是使用其它的方法得不到的.     

The influence of lattice structure on the dynamic performance of metal hollow sphere agglomerates

This paper addresses the dynamic performances of partially bonded or unbonded metallic hollow sphere structure (MHSS). Under the condition that the densities of MHSS are the same, three morphologies, that is, simple cubic (SC), body-centered cubic (BCC) and face-centered cubic (FCC) are investigated to see the topological effect of lattice structure on the dynamic performance of MHS agglomerates.     

Criterion for judging satisfaction of consistency conditions in rate-dependent constitutive relations

Based on irreversible thermodynamics, the criterion for judging the satisfaction of consistency conditions in rate-dependent constitutive relationship is deduced by introducing four basic hypotheses. Formulas for solving internal variables are given. It makes the rate-dependent model applicable no matter whether the consistency conditions can be satisfied or not. This research was funded by the National Natural Science Foundation of China (No. 59739180) and the Foundation of National Key Laboratory of Coastal and Offshore Engineering of Dalian University of Technology (No. 9701).     

Inter-cell spectrum efficiency improvement technology

Improvement in inter-cell spectrum efficiency is a valuable research topic in mobile communication system, which affects cell edge user experience especially. According to current research results, there are three methods to deal with inter-cell interference to improve inter-cell spectrum efficiency, including inter-cell interference randomization, inter-cell interference cancellation and inter-cell interference coordination. This paper analyzes three important inter-cell spectrum efficiency improvement technologies, soft frequency reuse (SFR), uplink power control, and downlink coordinated multi-point transmission/reception (CoMP), and relative research progress.     

A semismooth Newton method for nonlinear symmetric cone programming

In this paper, we employ the projection operator to design a semismooth Newton algorithm for solving nonlinear symmetric cone programming (NSCP). The algorithm is computable from theoretical standpoint and is proved to be locally quadratically convergent without assuming strict complementarity of the solution to NSCP.     

Lattice Boltzmann simulation of non-Newtonian flows past confined cylinders

A second-order lattice Boltzmann algorithm is used for Power-Law non-Newtonian flow simulation. The shear dependent behavior of the fluid is implemented through calculating the shear locally from the lattice distribution functions. A step by step verification procedure is taken to ensure the accuracy and the physical correctness of the numerical simulation. The flow past a series of tandem arrangement of two cylinders is computed in a confined domain. The effects of Reynolds number, the Power-Law index, and the distance between two cylinders on both the flow field and the drag coefficients of the cylinders are examined in detail.     

DECAY RATE OF SAINT-VENANT END EFFECTS FOR PLANE DEFORMATIONS OF PIEZOELECTRIC-PIEZOMAGNETIC SANDWICH STRUCTURES

This paper is concerned with the decay of Saint-Venant end effects for plane deformations of piezoelectric （PE）-piezomagnetic （PM） sandwich structures, where a PM layer is located between two PE layers with the same material properties or reversely. The end of the sandwich structure is subjected to a set of self-equilibrated magneto-electro-elastic loads. The upper and lower surfaces of the sandwich structure axe mechanically free, electrically open or shorted as well as magnetically open or shorted. Firstly the constitutive equations of PE mate- rials and PM materials for plane strain are given and normalized. Secondly, the simplified state space approach is employed to arrange the constitutive equations into differential equations in a matrix form. Finally, by using the transfer matrix method, the characteristic equations for eigen- values or decay rates axe derived. Based on the obtained characteristic equations, the decay rates for the PE-PM-PE and PM-PE-PM sandwich structures are calculated. The influences of the electromagnetic boundary conditions, material properties of PE layers and volume fraction on the decay rates are discussed in detail.