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81.
Toshihiko Myojo Kensei Ehara Hiromi Koyama Kikuo Okuyama 《Aerosol science and technology》2013,47(12):1178-1184
We describe a newly constructed annular-type differential mobility analyzer (DMA) with an effective electrode length of 60 cm, which is longer than that of our original DMA (40 cm length). This long DMA was developed to extend the classification size of particles measuring up to 1.5 μm. As an application of this DMA, the mean diameters and standard deviations were determined for six samples of monodisperse polystyrene latex (PSL) particles ranging from 0.94 to 1.27 μm in nominal diameter. These PSL particles suspended in double-distilled water were aerosolized by a glass nebulizer and then introduced into the DMA. The mean diameters and standard deviations of these PSL particles were calculated by Ehara's method and compared with the nominal diameters and uncertainties. There was good correlation between the nominal diameters of these samples—particularly for recently certified samples—and the measured diameters. Classification of aerosol particles more than 1 micrometer in diameter using this DMA will be useful for many purposes. 相似文献
82.
Mayumi Yamasaki Masayuki Takeda Tomoko Fukuda Ichiō Nanri 《New Generation Computing》2000,18(1):61-73
Waka is a form of traditional Japanese poetry with a 1300-year history. In this paper, we attempt to discover characteristics
common to a collection ofwaka poems. As a schema for characteristics, we use regular patterns where the constant parts are limited to sequences of auxiliary
verbs and postpostional particles. We call such patternsfushi. The problem is to automate the process of finding significantfushi patterns that characterize the poems. Solving this problem requires a reliable significance measure for the patterns. Brāzma
et al. (1996) proposed such a measure according to the MDL principle. Using this method, we report successful results in finding
patterns from five anthologies. Some of the results are quite stimulating, and we hope that they will lead to new discoveries.
Mayumi Yamasaki, M.A.: She received her B.E. and M.A. degrees from Kyushu Institute of Technology in 1997 and from Kyushu University in 1999, respectively.
Her research interests include machine discovery and datamining. Presently, she works at Fujitsu FIP Corporation.
Masayuki Takeda, Dr. Eng.: He is an Associate Professor in Department of informatics at Kyushu University. He received his B.S., M.S., and Dr. Eng.
degrees from Kyushu University in 1987, 1989 and 1996 respectively. His present research interests include pattern matching
algorithims, text compression, discovery science, information retrieval and natural language processing. He is a member of
Information Processing Society of Japan, Japanese Society for Artificial Intelligence and Japanese Society for Soft-ware Science
and Technology.
Tomoko Fukuda, M.A.: She is a Lecturer at Fukuoka Jo Gakuin University and at Junshin Women’s Junior College, She received her B.A. and M.A. degrees
from Fukuoka Women’s University in 1987 and from Kyushu University in 1992 respectively. Her present research interests are
in Japanese literature in the Heian period and classical 31-syllable Japanese poems. She is a member of Waka-Bungaku Kai (Society
for Study of Japanese Poems) and Chuko-Bungaku Kai (Society for Study of Japanese Literature in the Heian Period).
Ichiro Nanri, M.A.: He is an Associate Professor at Junshin Women’s Juior College. He received his B.A. and M.A. degrees from Kyushu University
in 1990 and 1995 respectively. His present research interests are in Japanese language in the Heian-Kamakura period and classical
31-syllable Japanese poems. He is a member of Kokugo Gakkai (Society for Study of Japanese Language) and Kuntengo Gakkai (Society
for Studyy of Old Language). 相似文献
83.
Toshihiko Myojo Akira Ogami Takako Oyabu Yasuo Morimoto Masami Hirohashi Masahiro Murakami Kenichiro Nishi Chikara Kadoya Isamu Tanaka 《Advanced Powder Technology》2010,21(5):507-512
Pulmonary health effects of fine particles and nanoparticles are overviewed in this paper, mainly based on the researches conducting in our laboratory. For the hazard assessment, we exposed rats to aerosolized asbestos-substitutes or nanoparticles aerosols (nickel oxide and titanium dioxide), and examined the biological and pathological effects of the particle on lung, a major target organ for the particles, and cytokines which are related to inflammation, fibrosis and carcinogenesis in the lung. It is essential to perform comprehensive evaluation of the toxicity of poorly soluble powder samples using the precise characterization data and exposure methods, such as single instillation or aerosol inhalation. 相似文献
84.
Keiji Tsukada Mitsuteru Yoshioka Yoshihiko Kawasaki Toshihiko Kiwa 《NDT & E International》2010,43(4):323-328
We have developed a magnetic flux leakage (MFL) system using magnetic resistive (MR) sensors for detecting two dimensional magnetic field components, and an induction coil that generates low magnetic field strengths and extremely low frequencies. The signal at each scanned measurement point (i) was divided by the signal strength Mmes,i and phase αi by a lock-in amplifier. Using the strength Mmes,i and phase αi, we calculated the imaginary part of the signal using the common phase β. By optimization of the common phase β to the imaginary part, the analyzed scanning data curve was shown to be effective in estimating the size (depth and diameter) of back-side pits on a ferrous plate. Comparing the two dimensional magnetic field components of leakage, the imaginary part of the y-component parallel to the induced magnetic field was found to be suitable for detecting the back-side pits. 相似文献
85.
Hiroki Nagasawa Akihiro Yamasaki Atsushi Iizuka Kazukiyo Kumagai Yukio Yanagisawa 《American Institute of Chemical Engineers》2009,55(12):3286-3293
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
86.
Shigeru Tanaka Kazuyuki Hokamoto Seiichi Irie Toshihiko Okano Zoran Ren Matej Vesenjak Shigeru Itoh 《Measurement》2011,44(10):2185-2189
Porous materials such as aluminum foam have been investigated for possible use as impact shock absorbers in transportation aeronautic applications. However, the response of aluminum foam during impacts at high velocities of more than 100 m/s is not yet fully understood. A high-velocity impact experiment was therefore carried out to clarify impact shock absorption properties of aluminum foam. A one-stage powder gun was used to accelerate an aluminum foam sample to impact a rigid wall. Velocity and deformation of the aluminum foam sample during impact was studied using a digital high-speed video camera, while the pressure wave in the aluminum foam sample was measured using a PVDF gauge. The experimental observations revealed uneven collapse of the aluminum foam sample structure during high speed impact with a general stress plateau effect, typical for cellular material structures when subjected to quasi-static loading. 相似文献
87.
Masashi Totokawa Syuichi Yamashita Kenji Morikawa Yoshihito Mitsuoka Toshihiko Tani Hiroaki Makino 《International Journal of Applied Ceramic Technology》2009,6(2):195-204
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass. 相似文献
88.
This paper describes a direct‐power‐controlled CVCF inverter and presents its experimentally examined operation characteristics. The most important feature of this strategy is the direct selection of the switching states of the CVCF inverter to restrict errors between the feedback and command values of active and reactive power. In addition, this paper presents a theoretical analysis of the relationship between the instantaneous power and the switching state, which is essential for deriving a switching‐state table for the controller. The feasibility of the proposed method was verified through several computer simulations and experimental tests using a 2.0‐kVA prototype setup. The output voltages were confirmed to be stable sinusoidal waveforms with a total harmonic distortion of 1.13% under nonlinear load conditions. Excellent voltage balance was achieved by the proposed strategy even under unbalanced load conditions. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(3): 62–69, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21023 相似文献
89.
Satoshi Azuma Hisanori Yamasaki Daisuke Itoh Takafumi Maruyama 《Electrical Engineering in Japan》2008,165(4):84-91
A newly proposed energy‐compensating active control is implemented to reduce the return current noise which is caused by inverter‐driven electric car systems. The energy‐compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25‐Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low‐frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20615 相似文献
90.
Yamasaki T. Shima K. Komori S. Takata H. Tamura T. Asai F. Ohno T. Tomisawa O. Terada H. 《Solid-State Circuits, IEEE Journal of》1989,24(4):933-937
A VLSI-oriented variable-length pipeline structure for data-driven processors is presented. Ordinary inline pipelines have the problem of minimizing the average total processing time through the pipeline, since subdivision of a function along the pipeline is usually optimized for the most complex operations in spite of the fact that simpler operations need fewer stages. As a solution to this problem, a variable-length pipeline scheme in which data go through only the necessary stages according to information contained within is proposed. The scheme has been implemented on a test chip to verify performance. The chip demonstrated a minimum fall-through time (data transmission time from input to output) of 14.4 ns and a data transmission rate in the pipeline of 59 megaword/s (that is, 1/16.9 ns) as a first-in first-out (FIFO) store. By modifying the data transfer control and allocating the processing functions corresponding to the data interval of 16.9 ns, this scheme is applicable as a high-performance processing unit for data-driven processors 相似文献