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In cutting-edge CPU/GPU hybrid clusters, such as Tianhe-1A, the aggregate CPU computing capability may amount to up to 1/3 of the aggregate GPU computing capability. It thus goes without saying that the CPUs and GPUs should jointly carry out the computational work. However, to effectively and simultaneously use both the hardware components requires great care when developing the parallel implementations. The challenges include (1) finding a balanced division of the workload between the CPU and GPU sides, and (2) hiding various overheads by overlapping computations with CPU-GPU data transfers and/or MPI communications. We study these issues in the context of real-world sedimentary basin simulations. Numerical experiments show that an appropriately devised CPU-GPU hybrid implementation is able to handle a global mesh resolution of 131,072*131,072, and a double-precision rate of 62 TFlops is achieved by using 1024 GPUs and 12288 CPU cores on Tianhe-1A. Such an extreme computing capability will be of great importance for carrying out high-resolution and continental-scale stratigraphic simulations in future.

We have studied two numerical strategies for solving a coupled system of dictinct nonlinear equations governing sediment transport in Lake Okeechobee. Using high-resolution bathymetry data of Lake Okeechobee, Florida, we study the numerical properties of the two strategies, from 1 core to 512 cores. The fully-explicit scheme is straightforward to implement and requires a relatively small amount of computation per time step. However, this simple numerical strategy has to use small time steps to ensure stability. These small time steps may render the explicit solver impractical for long-term and high-resolution basin simulations. As a comparison, we have implemented a semi-implicit scheme, where the two partial differential equations at each time step are solved implicitly in sequence. Numerical experiments show that this semi-implicit scheme is numerically stable even for very large time steps. Using a multicore-based cluster, we have carried out parallel simulations of sediment transport along a river chanel and into Lake Okeechobee.

In this paper, four kinds of materials (EVA with carbon black particle doped, Al, Cu and Au) were separately used as the electrode material with LLDPE sample in the space charge injection experiment. The results showed that samples with EVA electrode had larger amount of injection than the samples with metal electrodes. It's also found that metal electrode with larger work function would lead to smaller charge injection amount. In order to investigate the difference between EVA and the metal electrode except for their work function, a mode was built from the aspect of micro-structure of them. In this mode, the metal electrode was built with closed piled sphere, the diameter of the sphere is 4nm, and the EVA was composed of loose piled sphere with diameter of 40nm which was equal to the size of carbon particle in EVA. By the analysis of finite element, it's found that spheres in the EVA had larger local electric field and high electrical field region than the ones in the metal, so it's easier for the charge to be injected into the sample in EVA material with carbon black doped.

An inhomogeneous composite right-/left-handed (CRLH) transmission line (TL) is proposed and fabricated in the form of photonic super-lattice. Both the theoretical and experimental results demonstrate that, with two or more different building blocks in a periodic unit cell, band structures can be tuned by Bragg scattering in the left-handed frequency region in which the Bloch mode calculated shows the strong scattering. This work may provide a way to realize a kind of subwavelength size metamaterial filter or time delay line operating at some specific pass bands or stop bands.