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61.
Kosuke Aiuchi Ryo Moriyama Shohei Takeda Shunji Kitada Masaki Onozaki Yukuo Katayama 《Fuel Processing Technology》2007
A pre-heating vaporization technology of coal water slurry, CWS, was developed to increase the efficiency of coal gasification with the reduction of oxygen consumption. A CWS pre-heating experimental unit having a capacity of 2.0 tons-coal/day was manufactured. After the CWS was heated to 573 K at about 10 MPa, water in CWS was continuously vaporized in a tube of which the diameter increased gradually (2–10 mm I.D.), and dry coal particles with steam were atomized and fed to a vessel. No aggregation of coal particles was observed in the atomized samples. The temperature and the pressure distributions of the fluid were calculated with empirical heat transfer and pressure drop correlations. The calculated results well corresponded to the experimental data measured in some test points. Using the calculation model, a large scale apparatus of 100 tons-coal/day was designed using KNO3 + NaNO2 + NaNO3 molten salt as a heating medium. 相似文献
62.
Yamauchi Toshihiro Akao Yohei Yoshitani Ryota Nakamura Yuichi Hashimoto Masaki 《International Journal of Information Security》2021,20(4):461-473
International Journal of Information Security - Cyberattacks, especially attacks that exploit operating system vulnerabilities, have been increasing in recent years. In particular, if administrator... 相似文献
63.
Hatem S. Zurob Jinichiro Nakano Gary R. Purdy 《Journal of Phase Equilibria and Diffusion》2006,27(6):699-706
The presence of a concentration gradient across a thin liquid film leads to the phenomenon of isothermal liquid film migration
(LFM). In most cases, the concentration gradient is due to coherency stresses, and the migration of the liquid film results
in the relaxation of these stresses. It is also possible to envisage cases in which LFM occurs as a result of chemical solubility
differences between stable and metastable phases. Both situations are examined in this contribution with special emphasis
on the effect of adding a second solute element to the liquid phase. The kinetics of LFM is examined as a function of the
initial liquid concentration and the ratio of the solute diffusion coefficients in a model coherency-driven ternary system.
The growth of the Γ2 inside δ particles in the Zn-Fe-Al system is presented as a possible example of chemically driven LFM.
This article was presented at the Multicomponent-Multiphase Diffusion Symposium in Honor of Mysore A. Dayananda, which was
held during TMS 2006, the 135th Annual Meeting and Exhibition, March 12–16, 2006, in San Antonio, TX. The symposium was organized
by Yongho Sohn of University of Central Florida, Carelyn E. Campbell of National Institute of Standards and Technology, Richard
D. Sisson, Jr., of Worcester Polytechnic Institute, and John E. Morral of Ohio State University. 相似文献
64.
Kazunori Sakata Kosuke Nakano Hirofumi Miyahara Yasuhiro Matsubara Keisaku Ogi 《Journal of Thermal Spray Technology》2007,16(5-6):991-997
This article describes microstructure control aimed for wear-resistance improvement of Co-based (Co-Cr-W-B-Si) self-fluxing
alloy coating by diffusion treatment. The diffusion treatments of thermally sprayed Co-based self-fluxing alloy coating on
steel substrate were carried out at 1370-1450 K for 600-6000 s under an Ar gas atmosphere. Microstructural variations of the
coating and the interface between the substrate and the coating were investigated in detail. A proper diffusion treatment
precipitates two kinds of fine compounds in Co-based matrix. X-ray diffractometer (XRD) and electron probe microanalyzer (EPMA)
analysis revealed these precipitates to be a chromium boride dissolving cobalt and a tungsten boride containing cobalt and
chromium. The size of each precipitate became larger with increasing treatment temperature and time. A coating with the proper
size borides showed a superior wear-resistance.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
65.
66.
Truyen Van Phan Kha Cong Nguyen Masaki Nakagawa 《International Journal on Document Analysis and Recognition》2016,19(1):49-64
A Nom historical document recognition system is being developed for digital archiving that uses image binarization, character segmentation, and character recognition. It incorporates two versions of off-line character recognition: one for automatic recognition of scanned and segmented character patterns (7660 categories) and the other for user handwritten input (32,695 categories). This separation is used since including less frequently appearing categories in automatic recognition increases the misrecognition rate without reliable statistics on the Nom language. Moreover, a user must be able to check the results and identify the correct categories from an extended set of categories, and a user can input characters by hand. Both versions use the same recognition method, but they are trained using different sets of training patterns. Recursive X–Y cut and Voronoi diagrams are used for segmentation; k–d tree and generalized learning vector quantization are used for coarse classification; and the modified quadratic discriminant function is used for fine classification. The system provides an interface through which a user can check the results, change binarization methods, rectify segmentation, and input correct character categories by hand. Evaluation done using a limited number of Nom historical documents after providing ground truths for them showed that the two stages of recognition along with user checking and correction improved the recognition results significantly. 相似文献
67.
Wang P Behan G Kirkland AI Nellist PD Cosgriff EC D'Alfonso AJ Morgan AJ Allen LJ Hashimoto A Takeguchi M Mitsuishi K Shimojo M 《Ultramicroscopy》2011,111(7):877-886
Scanning confocal electron microscopy (SCEM) offers a mechanism for three-dimensional imaging of materials, which makes use of the reduced depth of field in an aberration-corrected transmission electron microscope. The simplest configuration of SCEM is the bright-field mode. In this paper we present experimental data and simulations showing the form of bright-field SCEM images. We show that the depth dependence of the three-dimensional image can be explained in terms of two-dimensional images formed in the detector plane. For a crystalline sample, this so-called probe image is shown to be similar to a conventional diffraction pattern. Experimental results and simulations show how the diffracted probes in this image are elongated in thicker crystals and the use of this elongation to estimate sample thickness is explored. 相似文献
68.
Hiroshi Mukawa Katsuyuki Akutsu Ikuo Matsumura Satoshi Nakano Takuji Yoshida Mieko Kuwahara Kazuma Aiki 《Journal of the Society for Information Display》2009,17(3):185-193
Abstract— A full‐color eyewear display with over 85% see‐through transmittance with a 16° horizontal field of view was developed. Very low color crosstalk, less than 0.008 Δu′v′ uniformity, and 120% NTSC color gamut were achieved. Waveguides with two in‐ and out‐coupling reflection volume hologram elements enabled a simple configuration that has an optical engine beside the user's temples. The reflection volume hologram elements used on the waveguides realized a small thickness of 1.4 mm for each waveguide, and an out‐coupling reflection volume hologram used as an optical combiner contributed a high see‐through transmittance of 85% due to its wavelength selectivity. However, there are technical challenges in achieving a reasonable screen size and quality color images with optics that utilize holographic waveguides because holograms have large chromatic dispersions compared to conventional optical elements such as lenses and mirrors. Approaches to overcome these issues are described. 相似文献
69.
Keisuke Fujita Kohji Higuchi Kazushi Nakano Koji Matsushita Tatsuyoshi Kajikawa Fumiho Chino 《Artificial Life and Robotics》2009,14(3):433-439
There is a need for robust current control of a pulse width modulation (PWM) power amplifier whose transient response characteristics
do not deteriorate with extensive load changes and/or direct-current power supply voltage changes. In this article, we propose
a digital robust controller with bumpless mode switching to control the current of a PWM power amplifier to satisfy the demands
and extend the range of an inductive load width. It is necessary to measure the value of the load in order to implement this
bumpless mode switching automatically depending on the load range. Therefore, a method of estimating the inductive load is
shown. The bumpless mode switching is automatically performed by estimating an inductive value without specifying the value
of the inductive load beforehand. That is, the value of the inductive load is estimated during the DDC execution, and the
control mode is automatically switched bumplessly according to this estimated value. A digital controller equipped with inductance
estimation and bumpless mode switching is realized by a DSP. Some experiments show that the digital controller with the proposed
bumpless mode switching can satisfy larger specifications. 相似文献
70.
Yamagishi J. Kobayashi T. Nakano Y. Ogata K. Isogai J. 《IEEE transactions on audio, speech, and language processing》2009,17(1):66-83
In this paper, we analyze the effects of several factors and configuration choices encountered during training and model construction when we want to obtain better and more stable adaptation in HMM-based speech synthesis. We then propose a new adaptation algorithm called constrained structural maximum a posteriori linear regression (CSMAPLR) whose derivation is based on the knowledge obtained in this analysis and on the results of comparing several conventional adaptation algorithms. Here, we investigate six major aspects of the speaker adaptation: initial models; the amount of the training data for the initial models; the transform functions, estimation criteria, and sensitivity of several linear regression adaptation algorithms; and combination algorithms. Analyzing the effect of the initial model, we compare speaker-dependent models, gender-independent models, and the simultaneous use of the gender-dependent models to single use of the gender-dependent models. Analyzing the effect of the transform functions, we compare the transform function for only mean vectors with that for mean vectors and covariance matrices. Analyzing the effect of the estimation criteria, we compare the ML criterion with a robust estimation criterion called structural MAP. We evaluate the sensitivity of several thresholds for the piecewise linear regression algorithms and take up methods combining MAP adaptation with the linear regression algorithms. We incorporate these adaptation algorithms into our speech synthesis system and present several subjective and objective evaluation results showing the utility and effectiveness of these algorithms in speaker adaptation for HMM-based speech synthesis. 相似文献