Parallel processing area extraction and data transfer number reduction for automatic GPU offloading of IoT applications

For Open IoT, we have proposed Tacit Computing technology to discover the devices that have data users need on demand and use them dynamically and an automatic GPU offloading technology as an elementary technology of Tacit Computing. However, it can improve limited applications because it only optimizes parallelizable loop statements extraction. Thus, in this paper, to improve performances of more applications automatically, we propose an improved method with reduction of data transfer between CPU and GPU. We evaluate our proposed offloading method by applying it to Darknet and find that it can process it 3 times as quickly as only using CPU.Comment: 6 pages, 4 figures, in Japanese, IEICE Technical Report, SC2018-3

Quantized Berry Phases for a Local Characterization of Spin Liquids in Frustrated Spin Systems

Recently by using quantized Berry phases, a prescription for a local characterization of gapped topological insulators is given. One requires the ground state is gapped and is invariant under some anti-unitary operation. A spin liquid which is realized as a unique ground state of the Heisenberg spin system with frustrations is a typical target system, since pairwise exchange couplings are always time-reversal invariants even with frustrations. As for a generic Heisenberg model with a finite excitation gap, we locally modify the Hamiltonian by a continuous SU(2) twist only at a specific link and define the Berry connection by the derivative. Then the Berry phase evaluated by the entire many-spin wavefunction is used to define the local topological order parameter at the link. We numerically apply this scheme for several spin liquids and show its physical validity.Comment: 6 pages. submitted for a proceeding of the conference (HFM2006) as an original pape

Possible huge enhancement in the radiative decay of the weal W boson into the charmed DsD_{s} meson

We point out that the rare decay mode $W^{\pm} \rightarrow \gamma + D^{\pm}_{s}$ could be spectacularly enhanced, with a branching ratio around $10^{-6}$ which is three order of magnitude larger than previous predictions. Its observation will determine the W boson mass with great accuracy, providing additional high precision tests of the standard model, as well as reveal eventual deviation from the trilinear non-abelian gauge coupling.Comment: 14, PAR/LPTHE 93 - 0