Tohru Sasaki

Some Simulation Techniques for Surface Analysis

STM (Scanning Tunneling Microscopy) is a kind of Scanning Probing Microscopy such as AFM, KFM etc, and they are powerful tools for surface analysis. Especially STM can observe the surface electronic structure of sample. But it does not directly observe atoms on the surface. Therefore it is important that STM images are compared with simulation images.

A Communication Method for Molecular Orbital Calculations on a Compact Embedded Cluster

In molecular orbital calculations, one of the high performance applications, execution time of Fock matrix construction is approximately 99% of all execution time. We propose a communication method for a parallel Fock matrix construction program on a compact embedded cluster (called EMDC: Embedded Middle Density Cluster). The parallel Fock matrix construction program was developed on EHPC project, and EMDC has been developing for low power and small space. Network architecture (tree-base network) of EMDC conforms to parallel Fock matrix construction program. In order to communicate among the system, we developed a communication library for tree-base network. In evaluations, EMDC system achieved high parallelization efficiency (13.2 speed-up ratios at 14 nodes).