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21.
Yasuo Ariki 《New Generation Computing》2000,18(4):341-357
Because of the media digitization, a large amount of information such as speech, audio and video data is produced everyday.
In order to retrieve data from these databases quickly and precisely, multimedia technologies for structuring and retrieving
of speech, audio and video data are strongly required. In this paper, we overview the multimedia technologies such as structuring
and retrieval of speech, audio and video data, speaker indexing, audio summarization and cross media retrieval existing today
for TV news detabase. The main purpose of structuring is to produce tables of contents and indices from audio and video data
automatically. In order to make these technologies feasible, first, processing units such as words on audio data and shots
on video data are extracted. On a second step, they are meaningfully integrated into topics. Furthermore, the units extracted
from different types of media are integrated for higher functions.
Yasuo Ariki, Ph.D.: He is a Professor in the Department of Electronics and Informatics at the Ryukoku University. He received his B.E., M.E.
and Ph.D. in information science from Kyoto University in 1974, 1976 and 1979, respectively. He had been an Assistant in Kyoto
University from 1980 to 1990, and stayed at Edinburgh University as visiting academic from 1987 to 1990. His research interests
are in speech and image recognition and in information retrieval and database. He is a member of IPSJ, IEICE, ASJ, Soc. Artif.
Intel. and IEEE. 相似文献
22.
Kusaka T Ueno M Miki T Kanenishi K Nagai Y Huang CL Okamoto Y Ogawa T Onodera M Itoh S Akiguchi I Sakamoto H 《Microscopy research and technique》2007,70(7):648-655
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus. 相似文献
23.
Yasuo Kinouchi Shoji Inabayashi Akira Satou Fumitoshi Shouji S. Inabayashi 《Artificial Life and Robotics》2000,4(2):53-56
To construct a “thinking-like” processing system, a new architecture of an adaptive associative memory system is proposed.
This memory system treats “images” as basic units of information, and adapts to the environment of the external world by means
of autonomous reactions between the images. The images do not have to be clear, distinct symbols or patterns; they can be
ambiguous, indistinct symbols or patterns as well. This memory system is a kind of neural network made up of nodes and links
called a localist spreading activation network. Each node holds one image in a localist manner. Images in high-activity nodes
interact autonomously and generate new images and links. By this reaction between images, various forms of images are generated
automatically under constraints of links with adjacent nodes. In this system, three simple image reaction operations are defined.
Each operation generates a new image by combining pseudofigures or features and links of two images.
This work was presented, in part, at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999 相似文献
24.
Islam Z Capatina D Ruff JP Das RK Trakhtenberg E Nojiri H Narumi Y Welp U Canfield PC 《The Review of scientific instruments》2012,83(3):035101
We present a pulsed-magnet system that enables x-ray single-crystal diffraction in addition to powder and spectroscopic studies with the magnetic field applied on or close to the scattering plane. The apparatus consists of a single large-bore solenoid, cooled by liquid nitrogen. A second independent closed-cycle cryostat is used for cooling samples near liquid helium temperatures. Pulsed magnetic fields close to ~30 T with a zero-to-peak-field rise time of ~2.9 ms are generated by discharging a 40 kJ capacitor bank into the magnet coil. The unique characteristic of this instrument is the preservation of maximum scattering angle (~23.6°) on the entrance and exit sides of the magnet bore by virtue of a novel double-funnel insert. This instrument will facilitate x-ray diffraction and spectroscopic studies that are impractical, if not impossible, to perform using split-pair and narrow-opening solenoid magnets. Furthermore, it offers a practical solution for preserving optical access in future higher-field pulsed magnets. 相似文献
25.
Thin SiO2 layers were deposited by atomic layer deposition (ALD) using either Bis-dimethylamino-silane (BDMAS: SiH2(N(CH3)2)2) or Tris-dimethylamino-silane (TDMAS: SiH(N(CH3)2)3) precursors. The purpose of this study is to evaluate these precursors for their suitability for ALD of hafnium (Hf)-silicate gate dielectrics. The advantages of these precursors are that the melting points and vapor pressures are moderate. The thickness of SiO2 deposited using ALD process is controlled by the number of growth cycles and the growth rate was different for each precursor, that for BDMAS being 1.5 times that for TDMAS at the same reactor pressure. The carbon impurity in the SiO2 film deposited using BDMAS was about half an order of magnitude less than that using for TDMAS. Furthermore, the carbon impurity was reduced to about the detection limit of secondary ion mass spectrometry after high temperature annealing at 1000 °C during 5 s. 相似文献
26.
Takuro Tomita Ayahito Uetake Tsutomu Asahina Kentaro Kayanuma Akihiro Murayama Yasuo Oka 《Journal of Superconductivity and Novel Magnetism》2005,18(3):405-410
Spin injection processes in the double quantum dots of ZnSe-based diluted magnetic semiconductors are discussed. Double quantum
dots are fabricated from ZnSe-based double quantum wells by electron beam lithography and wet etching. In these samples, the
photo-excited carriers in the magnetic dots are injected into the non-magnetic dots. The circular polarization degrees of
photoluminescence from the non-magnetic dots are measured by micro-photoluminescence measurement system under the magnetic
field up to 5 T. The maximum spin polarization degrees of injected carriers determined from our experiment are 10% for double
quantum wells and 15% for double quantum dots. The spin injection efficiency was estimated both from the observed circular
polarization degree and the diffusion length of carriers. We concluded that the spin injection efficiency is increased in
the double quantum dots. 相似文献
27.
Suppose that some particular link in the Internet is currently
congested.
A natural solution is to try to make packets bypass that link.
This can be done by increasing the cost of that link intentionally,
say from a
1 to a
2, since the Internet uses shortest-path
routing. Unfortunately, however, this often causes temporary loops
for packet traveling, called routing loops. In this paper
we show that routing loops can be avoided by increasing the cost
of the link not directly from a
1 to a
2 but through an
intermediate value, a
3, i.e., from a
1 to a
3 and then
to a
2.
We may need several
intermediate values.
We show that in this case
the greedy strategy,
namely, raising the cost as much as possible in each step,
is optimal. 相似文献
28.
Piezoresistivities of vapor‐grown carbon fiber/silicone foams for tactile sensor applications 下载免费PDF全文
Due to the growing demand for tactile sensors, the possibility of detecting an external uniaxial pressure by the piezoresistive measuring of a conductive filler/elastomer composite was investigated. A series of piezoresistive models are discussed. Novel highly sensitive piezoresistive foams with excellent elasticity were fabricated using vapor‐grown carbon fiber (VGCF), two‐component silicone elastomer and a new type of thermally expandable micro beads foaming agent to overcome the disadvantages of the silicone elastomer in the utilization of a tactile sensor. Deformations of the foams caused by uniaxial pressure were observed using scanning electron microscopy from cross‐sections. Effects of the VGCF and the foaming agent on the piezoresistivitiy were investigated. The piezoresistive mechanisms of the foams are discussed according to the measurements, and good fit was found between the theoretical calculations and the experimental piezoresistivity measurements. It is found that the addition of the micro beads foaming agent can improve the piezoresistivity of the VGCF/silicone foam and increase the sensitivity and repeatability for its application in a tactile sensor. © 2016 Society of Chemical Industry 相似文献
29.
Tokuyuki Yoshida Yasuo Yoshioka Hideki Takahashi Kazuki Misato Takahide Mori Toshiro Hirai Kazuya Nagano Yasuhiro Abe Yohei Mukai Haruhiko Kamada Shin-ichi Tsunoda Hiromi Nabeshi Tomoaki Yoshikawa Kazuma Higashisaka Yasuo Tsutsumi 《Nanoscale research letters》2014,9(1):532
Although amorphous silica nanoparticles are widely used in the production of food products (e.g., as anticaking agents), there is little information available about their absorption and biological effects after oral exposure. Here, we examined the in vitro intestinal absorption and in vivo biological effects in mice of orally administered amorphous silica particles with diameters of 70, 300, and 1,000 nm (nSP70, mSP300, and mSP1000, respectively) and of nSP70 that had been surface-modified with carboxyl or amine groups (nSP70-C and nSP70-N, respectively). Analysis of intestinal absorption by means of the everted gut sac method combined with an inductively coupled plasma optical emission spectrometer showed that the intestinal absorption of nSP70-C was significantly greater than that of nSP70. The absorption of nSP70-N tended to be greater than that of nSP70; however, the results were not statistically significant. Our results indicate that silica nanoparticles can be absorbed through the intestine and that particle diameter and surface properties are major determinants of the degree of absorption. We also examined the biological effects of the silica particles after 28-day oral exposure in mice. Hematological, histopathological, and biochemical analyses showed no significant differences between control mice and mice treated with the silica particles, suggesting that the silica nanoparticles evaluated in this study are safe for use in food production. 相似文献
30.
Takafumi Ishii Takuya Maie Naofumi Kimura Yuki Kobori Yasuo Imashiro Jun-ichi Ozaki 《International Journal of Hydrogen Energy》2017,42(23):15489-15496
The use of carbon cathode catalysts in polymer electrolyte fuel cells instead of the current platinum catalysts is attracting increasing attention. We claim that two factors are important for enhancing the activity of carbon cathode catalysts in the oxygen reduction reaction (ORR): the formation of a nanoshell structure and co-doping with boron and nitrogen. Herein, we investigate the preparation and characterization of active ORR carbon catalysts that combine the above factors. Boron and nitrogen (BN)-doped nanoshell-containing carbon (BN-NSCC) was prepared by carbonizing a mixture of poly(furfuryl alcohol), cobalt phthalocyanine, melamine, and a trifluoroborane–methanol complex at 1000 °C. Transmission electron microscopy and X-ray photoelectron spectroscopy revealed the formation of nanoshell structures with distorted graphitic layers and the introduction of boron and nitrogen atoms, respectively. The ORR activity was evaluated in oxygen-saturated 0.5 mol dm?3 H2SO4 using Koutecky–Levich analysis. The BN-NSCC showed an eight to ten times higher ORR activity than undoped NSCC, with an increased number of electrons participating in the reaction. Tafel analysis revealed a change in the rate-determining step caused by BN-doping. Thus, the combination of a nanoshell structure and co-doping with boron and nitrogen was found to improve the ORR activity of carbon catalysts. 相似文献