作者：
FUJIWARA, ETANAKA, TMemberFaculty of Engineering
Tokyo Institute of Technology Tokyo Japan 152 Eui Fujiwara:received his B.S. and M.S. degrees in Electronics Engineering in 1968 and 1970
respectively and his Dr. of Eng. degree in 1981 all from Tokyo Institute of Technology. In 1970 he joined the NTT Musashino Electrical Communication Laboratories and engaged in developing PIPS-1 and PIPS-11 computer systems. In 1988 he joined the Department of Computer Science Tokyo Institute of Technology as an Associate Professor. In 1990 he became a full Professor. He was a Visiting Professor at the Center for Advanced Computer Studies the University of Southwestern Louisiana from June 1985 to July 1986. His current research interests include coding theory for computers fault-tolerant memories VLSI defect-toleranceand WSI systems. He is a co-author ofError Control Coding for Computer Systems(Prentice-Hall1989) EssentiaLF of Error-Correcting Coding Techniques (Academic Press 1990) and other books. Dr. Fujiwara received the Young Engineer Award from the I.E.I.C.E. in 1978 and the Teshima Memorial Research Award in 1991. He is a senior member of the IEEE and a member of the Information Processing Society Japan. Associate Member
Because of its capability of high-speed search, the associative memory (CAM) is expected to be used in a variety of information processing systems. In this paper, novel fault-tolerant techniques which are effective fo...
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Because of its capability of high-speed search, the associative memory (CAM) is expected to be used in a variety of information processing systems. In this paper, novel fault-tolerant techniques which are effective for on-line use are proposed for TLB which is an example of the application of CAM. First, fault and error models of the TLB consisting of the CAM part and the SRAM part are clarified. Then, the fault-tolerant techniques for these faults and errors, such as distance separable technique, cod-ing technique, simplified 1-out-of-n check and graceful degradation, are proposed. The distance separable technique which encodes the data stored in the CAM part is the one which masks the faulty CAM part and prevents errors from propagating to the subsequent circuits. The coding technique checks the one-to-one correspondence between the data in the CAM and those in SRAM by using the SEC-DED code with byte error detection capability, i.e., SEC-DED-SbED code, and at the same time it detects and corrects errors in the data stored in SRAM. The simplified 1-out-of-n check processes association errors. The graceful degradation gives a flag in the faulty memory section and prevents it from being used. The methods proposed in this paper are evaluated from area augmentation and error detection capability perspectives. The results show that the fault-tolerant TLB with 32 virtual address bits, 32 physical address bits and 128 entries gives single fault detection probability of nearly 99 percent with 28 percent area increase.
In order to solve the speed problem and shallow reasoning problem met in current research in fault diagnosis expert system, this paper presents a model based parallel fault diagnosis expert system for energy managemen...
The influence of static magnetic fields on the behavior of oxygen dissolved m an aqueous solution was studied in order to clarify the interaction mechanism of dynamic movements of dissolved oxygen with magnetic fields...
The influence of static magnetic fields on the behavior of oxygen dissolved m an aqueous solution was studied in order to clarify the interaction mechanism of dynamic movements of dissolved oxygen with magnetic fields and to broaden the basic understanding of biological effects of magnetic fields. A horizontal type of superconducting magnet with a bore 100 mm in diameter was used. A cylindrical chamber filled with distilled water was exposed to magnetic fields up to 8 T and a gradient of 50 T/m. The spatial distribution of oxygen concentration dissolved in water was measured by a dissolved oxygen meter. A clear redistribution of oxygen concentration was observed, and the dissolved oxygen concentration increased more than 10% around the center of the magnet.
The power transfer characteristics of an asymmetric nonlinear directional coupler (NLDC), which consists of a nonlinear waveguide with a core of Kerr-like medium and a linear waveguide, are analyzed using the beam pro...
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The power transfer characteristics of an asymmetric nonlinear directional coupler (NLDC), which consists of a nonlinear waveguide with a core of Kerr-like medium and a linear waveguide, are analyzed using the beam propagation method. The numerical results demonstrate that the asymmetric NLDC is useful for constructing an optical power filter. (C) 1994 John Wiley & Sons, Inc.
Diagnosis of anemia depends upon the observation of variations in color, shape and gray level distribution inside the Red Blood Cells (RBC's). The most important of all is the variation in the outer contour of an ...
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It is reported that the first partial derivative of the phase distribution for a transparent object can be measured automatically by a personal computer with an image processor. The moire pattern is formed by superimp...
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In radar imaging the authors consider the double passage effect under a strong turbulence model, the authors have analyzed holographic imaging and evaluated the effect on the imaging. Some numerical analyses show that...
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In radar imaging the authors consider the double passage effect under a strong turbulence model, the authors have analyzed holographic imaging and evaluated the effect on the imaging. Some numerical analyses show that the double passage effect produces an intensity enhancement at the center of the image of size larger than the wavelength of an incident wave. The authors trying to restore the image distortion and improve the image resolution by applying a filtering technique.
The problem of reconstructing a medium parameter in an object from measurements of the field scattered when the object is illuminated by known sources has become of great interest in nondestructive testing, remote sen...
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The problem of reconstructing a medium parameter in an object from measurements of the field scattered when the object is illuminated by known sources has become of great interest in nondestructive testing, remote sensing, biomedical imaging and so on. In the inverse problem mentioned above, the relation between two unknowns, the field and the medium parameter in the object, is in general nonlinear and hence various reconstruction methods have been developed to give a high-resolution image in situations where the Born or Rytov approximation is not valid. To overcome such difficulties, we propose a novel reconstruction algorithm using a boundary matching technique. In our algorithm, on the assumption that the object may be divided into piecewise homogeneous regions, the field in the object is analytically expressed in terms of wave functions in each region and the mean square error between the measured and calculated fields on the boundary of the object is introduced to estimate the convergence of our procedure. We apply this algorithm to the reconstruction of circularly distributed complex refractive-index in the E-polarized plane wave.
This paper presents a spatial filtering method for reducing ill-effects of atmospheric turbulence on holographic imaging using airborne radars. The method is based on the spatially weighting of amplitudes of received ...
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This paper presents a spatial filtering method for reducing ill-effects of atmospheric turbulence on holographic imaging using airborne radars. The method is based on the spatially weighting of amplitudes of received waves and is examined by showing graphically the average strip-image which is holographically reconstructed by using exponential weight functions. The introduction of the weight functions yields fairly good restoration of images degraded by atmospheric turbulence and may be useful for image reconstruction in the case of extremely strong turbulence.
The question of whether magnetic fields affect enzymatic activities or not is of considerable interest in biochemistry and in biomagnetics. Xanthine oxidase, contained in liver, lungs, intestine, and other organs, cat...
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The question of whether magnetic fields affect enzymatic activities or not is of considerable interest in biochemistry and in biomagnetics. Xanthine oxidase, contained in liver, lungs, intestine, and other organs, catalyzes the degradation of hypoxanthine to xanthine, and xanthine to uric acid, which is the terminal waste of purine nucleotides in mammals. During the oxidation of xanthine, the enzyme releases superoxide anion radicals as intermediates which reduce ferricytochrome c (Fe3+). Superoxide anion, as well as any type of free radical, is also paramagnetic. The study is focused on whether these magnetically related enzymatic activities can be affected by magnetic fields. There is a possibility that free radicals, as intermediates, can be modified by magnetic fields of specific intensities. In our previously reported study, we examined a possible effect of magnetic fields up to 1.0 T on biochemical reaction catalyzed by xanthine oxidase, and obtained negative results. In the present abstract, we examine the effect of magnetic fields up to 8 T on this oxidation‐reduction process. Reduced cytochrome c (Fe2+) has an absorption maximum at 550 nm which can be detected by a spectrophotometer. Xanthine oxidase was assayed by superoxide dismutase—inhibitable reduction of cytochrome c. We measured optical absorbance of reduced cytochrome c by superoxide anion which was produced by the reaction catalyzed by xanthine oxidase. The absorbances of the mixture exposed to an 8 T magnetic field at 25?°C were higher than control samples in the re‐oxidation proces of cytochrome c. The results show that the 8 T magnetic fields altered the rate of reduction of cytochrome c by superoxide anion which was produced by the reaction catalyzed by xanthine oxidase. It may conclude that the electron transfer from xanthine to molecular oxygen or the transfer from superoxide anion to cytochrome c, can be affected by the magnetic fields up to 8 T.
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