Analysis of Liquefiable Sand Deposits Using Gravel Drains

In this paper, based on the simplified assumption about seismic pore water pressure a partial differential equation of 3-D axi-symmetrical problem which takes into account of the generation, diffusion and dissipation of seismic pore water pressure is presented. This equation is then solved by the method of separation of variables and 5-function and a mathematical formula for residual pore water pressure is obtained. The formula can be used in the calculation and design of the gravel drains installed in the sand layer prone to liquefy. The computed results by this formula are presented in a series of charts which can be conveniently used ln design

Effect of Canyon Shape on Longitudi-Vibration of Earth Dam

In this paper, the effects of narrow and sloping canyons on the longitudinal dynamic response of earth dams is investigated by a simplified method for 3-D dynamic analysis. Analytical results for earth dams with several width to height ratios are compared with the results of plane strain solutions for comparable sections. For an embankment in a triangular valley with a width to height ratio of 1~2 and subjected to earthquake motions, the computed max. accelerations at the midsection were about 30 to 50% higher in a simplified 3-D response analysis than in a plane strain analysis. On the other hand the computed max. displacements, max. velocity, and max. shear stresses for the same section in 3-D analysis were generally about one half the values to 2/3 the values computed from plane strain analysis. It is concluded that the longitudinal dynamic response of an embankment is significantly affected by the width to height ratio of canyon in which it is constructed

Energy-Efficient Multi-View Video Transmission with View Synthesis-Enabled Multicast

Multi-view videos (MVVs) provide immersive viewing experience, at the cost of heavy load to wireless networks. Except for further improving viewing experience, view synthesis can create multicast opportunities for efficient transmission of MVVs in multiuser wireless networks, which has not been recognized in existing literature. In this paper, we would like to exploit view synthesis-enabled multicast opportunities for energy-efficient MVV transmission in a multiuser wireless network. Specifically, we first establish a mathematical model to characterize the impact of view synthesis on multicast opportunities and energy consumption. Then, we consider the optimization of view selection, transmission time and power allocation to minimize the weighted sum energy consumption for view transmission and synthesis, which is a challenging mixed discrete-continuous optimization problem. We propose an algorithm to obtain an optimal solution with reduced computational complexity by exploiting optimality properties. To further reduce computational complexity, we also propose two low-complexity algorithms to obtain two suboptimal solutions, based on continuous relaxation and Difference of Convex (DC) programming, respectively. Finally, numerical results demonstrate the advantage of the proposed solutions.Comment: 22 pages, 6 figures, to be published in GLOBECOM 201

Effect of magnetic field on the spin resonance in FeTe(0.5)Se(0.5) as seen via inelastic neutron scattering

Inelastic neutron scattering and susceptibility measurements have been performed on the optimally-doped Fe-based superconductor FeTe(0.5)Se(0.5), which has a critical temperature, Tc of 14 K. The magnetic scattering at the stripe antiferromagnetic wave-vector Q = (0.5,0.5) exhibits a "resonance" at ~ 6 meV, where the scattering intensity increases abruptly when cooled below Tc. In a 7-T magnetic field parallel to the a-b plane, Tc is slightly reduced to ~ 12 K, based on susceptibility measurements. The resonance in the neutron scattering measurements is also affected by the field. The resonance intensity under field cooling starts to rise at a lower temperature ~ 12 K, and the low temperature intensity is also reduced from the zero-field value. Our results provide clear evidence for the intimate relationship between superconductivity and the resonance measured in magnetic excitations of Fe-based superconductors.Comment: 4 pages, 3 figure

Conductance oscillation and quantization in monoatomic Al wires

We present first-principles calculations for the transport properties of monoatomic Al wires sandwiched between Al(100) electrodes. The conductance of the monoatomic Al wires oscillates with the number of the constituent atoms as a function of the wire length, either with a period of four-atom for wires with the typical interatomic spacing or a period of six-atom with the interatomic spacing of the bulk fcc aluminum, indicating a dependence of the period of conductance oscillation on the interatomic distance of the monoatomic Al wires