Katsuhiro Nakajima

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In this paper, we propose a rewritable data embedding scheme on MPEG coded data domain for content managements including DRM, content controlling and indexing. Data embedding is performed in a block by block basis, where the length of zero run and the value of dummy AC component of quantized DCT coefficients are used as a data carrier. In the detection(More)
  • K. Nakajima
  • 2004
Efficient parallel preconditioned iterative linear solvers for unstructured grid have been developed for symmetric multiprocessor (SMP) cluster architectures with vector processors such as the Earth simulator. Three types of preconditioning methods (ICCG, multigrid and selective-blocking for contact problems) have been developed and performance has been(More)
Calcinated egg shell (Egg-CaO), of which the main component is calcium oxide, was evaluated in the forms of powder and aqueous solutions for their efficacies as disinfectants against avian influenza virus (AIV), Newcastle disease virus (NDV), infectious bursal disease virus (IBDV), Salmonella Infantis and Escherichia coli. Egg-CaO powder inactivated these(More)
The capacity of slightly acidic hypochlorous acid water (SAHW), in both liquid and spray form, to inactivate bacteria was evaluated as a potential candidate for biosecurity enhancement in poultry production. SAHW (containing 50 or 100 ppm chlorine, pH 6) was able to inactivate Escherichia coli and Salmonella Infantis in liquid to below detectable levels(More)
  • K. Nakajima
  • 2005
Parallel iterative linear solvers for unstructured grids in FEM application, which were developed for the Earth Simulator (ES), have been ported to various types of SMP cluster supercomputers. Performance of flat-MPI and hybrid parallel programming model has been compared using more than 100 SMP nodes of ES, Hitachi SR8000 and IBM SP-3. Effect of coloring(More)
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