Toshinori Kojima

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This paper introduces a scalable FPGA implementation of a stochastic simulation algorithm (SSA) called the next reaction method. There are some hardware approaches of SSAs that obtained high-throughput on reconfigurable devices such as FPGAs, but these works lacked in scalability. The design of this work can accommodate to the increasing size of target(More)
In order to simulate large scale biological models with a reconfigurable FPGA-based biochemical simulator system, reduction of required resources are essential. This paper proposes a method which combines common terms in rate law functions appeared in biochemical models and generates a shared hardware module used for numerical integration. In this approach,(More)
Stochastic simulation of biochemical systems has become one of major approaches to study life processes as system, yet is a computational challenge to run the simulation due to its vast calculation cost. This paper shows the implementation and evaluation of a stochastic simulation algorithm (SSA) called "first reaction method" on an FPGA-based biochemical(More)
Network coordinates (NCs) construct a logical space which enables efficient and accurate estimation of network latency. Although many researchers have proposed NCbased strategies to reduce the lookup latency of distributed hash tables (DHTs), these strategies are limited in the improvement of the lookup latency; the nearest node to which a query should be(More)
Prediction of soil characteristics over large areas is desirable for environmental modeling. In arid environments, soil characteristics often show strong ecological connectivity with natural vegetation, specifically biomass and/or canopy cover, suggesting that the soil characteristics may be predicted from vegetation data. The objective of this study was to(More)
A speed sensorless vector control (SLV) for rolling stock is introduced. The proposed SLV system meets the typical performance parameters of rolling stock, including initial speed estimation, stability in one-pulse mode operation, multiple motor drive operations, readhesion control using slip detection by estimated speed, and so on. In particular, we(More)
As demand for high fidelity multimedia content has soared, content distribution has emerged as a critical application. Large multimedia files require effective content distribution services such as content distribution networks (CDNs). A recent trend in CDN development is the use of peer-to-peer (P2P) techniques to enhance scalability, fault resilience, and(More)
As a countermeasure to the greenhouse effect, afforestation in arid areas has been proposed and tested in an arid area of Western Australia. According to the CDM/JI guidelines set by UNFCCC, the sequestered carbon amount accountable as carbon credit was estimated in this study. First, the sequestered carbon amount by planted trees was measured by repeated(More)
Mathematical simulation of biological processes is a big challenge in both of biology and computer science. This enables biologists to approach the mechanism of life as systems, however, it's an extremely computation intensive tasks. We've developed an FPGA-based hardware accelerator for biochemical simulations. This accelerator has a dedicated pipeline to(More)