Masaaki Shimizu

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We have been developing a large scale PC cluster named PACS-CS (Parallel Array Computer System for Computational Sciences) at Center for Computational Sciences, University of Tsukuba, for wide variety of computational science applications such as computational physics, computational material science, computational biology, etc. We consider the most(More)
We have examined a tonal system of modern Hanoi dialect of Vietnamese. This has been described for a long time as a pitch contour prominent system with secondary phonatory variations. The present study aims to propose certain laryngeal features, [tense] and [glottal constriction], in addition to the former prosodic feature, [high], to cover the overall(More)
Enumeration of chemical graphs satisfying given constraints is one of the fundamental problems in chemoinformatics and bioinformatics since it leads to a variety of useful applications including structure determination of novel chemical compounds and drug design. In this paper, we consider the problem of enumerating all tree-like chemical graphs from a(More)
Turning towards exascale systems and beyond, it has been widely argued that the currently available systems software is not going to be feasible due to various requirements such as the ability to deal with heterogeneous architectures, the need for systems level optimization targeting specific applications, elimination of OS noise, and at the same time,(More)
Dedicated processors that are specialized for numerical computations, such as the Cell/B.E. and vector processors, tend to have low performance in the integer computations required by operating systems. To solve this problem, we propose a remote process and remote file I/O management architecture that enables processes on compute nodes that have dedicated(More)
Mobile ad-hoc networks (MANETs) are expected to substitute for existing networks when the latter are disrupted by a disaster, etc. However, it has been pointed out that communication quality of MANETs is lower than that of existing networks, and that the use of transmission control protocol (TCP) over MANETs extremely degrades its performance. This paper(More)
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