http://hdl.handle.net/11605/108 2017-09 Tue, 14 Apr 2026 02:39:09 GMT 2026-04-14T02:39:09Z http://hdl.handle.net/11605/110 タイトル: Effectiveness of a Fast Switching Function of Continuous Video Signals　on Unmanned Vehicle Controls 著者名: HADAMA, Hisaya; OGURA, Masaki; NAKAMURA, Ryohei 抄録: This research aims at the development of an affordable unmanned vehicle (UV) that can be controlled through cellular networks. Currently, given the instability of the packet transmission qualities of the cellular network, communication is likely to be interrupted occasionally. The interruption of the control signal would impede the precise real-time control of a UV. However, we believe that it might be possible to decrease the occurrence of these interruptions by transmitting communication over multiple wireless networks, given their availability in numerous areas. Accordingly, in this paper, we propose a fast switching function that can be used to facilitate video signal transmission and assist effective UV control. We begin by elucidating the availability and packet transmission qualities of commercial networks, then provide a detailed explanation of our proposal, and finally conclude with our evaluation results. Thu, 31 Aug 2017 15:00:00 GMT http://hdl.handle.net/11605/110 2017-08-31T15:00:00Z http://hdl.handle.net/11605/109 タイトル: Basic Numerical Simulation of Large-Scale Plume Activity Due to the Circum-Pacific Lithosphere Subduction and Implications for the Elementary Process Associated with the Static-Layered Terrestrial Mantle 著者名: EGUCHI, Takao; ISHIDA, Mizuho; MATSUBARA, Kiyoshi; MURAKOSHI, Takumi; IWASE, Yasuyuki 抄録: To unveil the global dynamics of long-term lithosphere subduction along the circum-Pacific Ocean and relationship with large-scale mantle plume activity, we conducted 3-D spherical numerical simulations using a newly developed program. This program is based on the finite difference method with the Boussinesq (incompressible) approximation and temperature-dependent viscosity. To obtain a higher precision time integral, we adopted the Newton method. In addition, the preconditioned ‘Bi-CGSTAB’ (Bi-Conjugate Gradient Stabilized) method was incorporated to solve the Jacobian matrix of five finite difference equations for the velocity vector, pressure, and temperature. The preconditions used were matrix-matrix multiplication and incomplete LU factorization. We subsequently modeled circum-Pacific lithosphere subduction using the initial condition of a cool ring, at the base of the upper mantle along the equatorial great circle, imposed on the horizontally uniform temperature field with thermal boundary layers. The results indicated major upwellings at latitudes ± 30~40° as a response function. Secondary rising systems at both polar regions were clear. Our result numerically manifests part of the Green function-like elementary processes of large-scale passive flows within the static layered terrestrial mantle. Thu, 31 Aug 2017 15:00:00 GMT http://hdl.handle.net/11605/109 2017-08-31T15:00:00Z