A stream layered cooperative relay multicast scheme and capacity analysis in cellular systems

It is widely believed that cooperative relay technologies can improve the throughput of multicasting in mobile cellular networks significantly, however, the mobility of the relay terrninals may cause frequent relay link outage. This paper proposes a stream layered cooperative relay scheme to deal with this problem. In order to study the characteristics of layered relay channels in the scheme, the capacity region is determined based on a single and a multi relay abstract model with streams layering. Besides, to satisfy the cellular network scenario, the results are extended to a wireless Gaussian channel model. The analysis and simulation results show that the scheme guarantees the continuity of the multicast streams, and maintains the high bandwidth of relay channel, with a slight loss on system capacity.

Evolved data scheduling scheme based on layered P2P streaming in mobile network

To relieve the negative effect brought by the intricate wireless network environment and unstable user behavior in layered mobile peer-to peer（P2P） streaming service, an evolved layered P2P （E-LP2P） data scheduling scheme in the process of service delivery is introduced in this paper. The data in base layer is scheduled according to its importance in streaming play to guarantee the basic play of streaming. The data in enhancement layer is scheduled according to the characters of streaming data, including its position and amount in server peer set in a multiple tied way towards the data in enhancement layer. To cope with the layer jitter caused by the fluctuation of bandwidth, jitter prevent mechanism is used to adjust the highest layer dynamically during the process of data scheduling. Simulation results show that the E-LP2P can provide good quality of service（QoS） performance in terms of throughput, layer delivery ratio, server load and useless packet ratio.

Dimension Splitting Method for the Three Dimensional Rotating Navier-Stokes Equations

In this paper, we propose a dimensional splitting method for the three dimensional （3D） rotating Navier-Stokes equations. Assume that the domain is a channel bounded by two surfaces and is decomposed by a series of surfaces i into several sub-domains, which are called the layers of the flow. Every interface i between two sub-domains shares the same geometry. After establishing a semi-geodesic coordinate （S-coordinate） system based on i, Navier-Stoke equations in this coordinate can be expressed as the sum of two operators, of which one is called the membrane operator defined on the tangent space on i, another one is called the bending operator taking value in the normal space on i. Then the derivatives of velocity with respect to the normal direction of the surface are approximated by the Euler central difference, and an approximate form of Navier-Stokes equations on the surface i is obtained, which is called the two-dimensional three-component （2D-3C） Navier-Stokes equations on a two dimensional manifold. Solving these equations by alternate iteration, an approximate solution to the original 3D Navier-Stokes equations is obtained. In addition, the proof of the existence of solutions to 2D-3C Navier-Stokes equations is provided, and some approximate methods for solving 2D-3C Navier-Stot4es equations are presented.