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991.
The authors previously constructed a highly accurate fast face recognition optical correlator (FARCO) [E. Watanabe and K.
Kodate: Opt. Rev. 12 (2005) 460], and subsequently developed an improved, super high-speed FARCO (S-FARCO), which is able to process several hundred
thousand frames per second. The principal advantage of our new system is its wide applicability to any correlation scheme.
Three different configurations were proposed, each depending on correlation speed. This paper describes and evaluates a software
correlation filter. The face recognition function proved highly accurate, seeing that a low-resolution facial image size (64
× 64 pixels) has been successfully implemented. An operation speed of less than 10 ms was achieved using a personal computer
with a central processing unit (CPU) of 3 GHz and 2 GB memory. When we applied the software correlation filter to a high-security
cellular phone face recognition system, experiments on 30 female students over a period of three months yielded low error
rates: 0% false acceptance rate and 2% false rejection rate. Therefore, the filtering correlation works effectively when applied
to low resolution images such as web-based images or faces captured by a monitoring camera. 相似文献
992.
S. Bianco A. M. Bragadireanu F. L. Fabbri C. Guaraldo M. Iliescu T. M. Ito V. Lucherini C. Petrascu M. Bregant E. Milotti A. Vacchi E. Zavattini M. Augsburger D. Chatellard P. Knowles F. Mulhauser L. A. Schaller L. Schellenberg H. Schneuwly J. P. Egger D. Varidel W. H. Breunlich M. Cargnelli B. Gartner R. King B. Lauss J. Marton J. Zmeskal T. Ponta S. N. Nakamura T. Koike R. S. Hayano M. Hori T. Ishikawa T. Ishiwatari M. Iwasaki Y. Akaishi G. Beer A. C. Sanderson R. Seki 《La Rivista del Nuovo Cimento (1969-1970)》1999,22(11):1-45
993.
T. Ishikawa S. Tokonami S. Yoshinaga Y. Narazaki 《Journal of Radioanalytical and Nuclear Chemistry》2005,267(1):85-88
Summary A preliminary survey of airborne and waterborne radon concentrations was given for an area where groundwater is used as a
source of public water supply. The average of the waterborne radon concentrations was 77 Bq/l for 36 samples and that of airborne
radon concentrations was 18 Bq/m3for ten houses. It is concluded that the exposure dose due to radon-in-water is likely to be much smaller than the total dose
from natural radiation. 相似文献
994.
A porous elastic road surface (PERS) is superior to drainage asphalt pavement for reducing highway traffic noise. In earlier research and development, for example using a test track, the difference in sound power level (Lw) of cars has been regarded as the noise reduction effect since it was not possible to measure the change in equivalent continuous A-weighted sound pressure level (Leq) for a series of vehicles on such a limited length of surface. As the result of a comparatively major test construction on a highway, have measured the noise reduction effect of PERS as the difference in Leq. First, we measured the motor vehicle Lw and Leq on each section. However, we found that the neighbouring paved sections also influenced Leq. Next, we calculated Leq according to a highway traffic noise model, using the values of Lw measured in the different paved sections. Since the calculated Leq corresponded approximately with the measured Leq, we could verify the validity of the measured Lw. We again calculated Leq, assuming that each pavement is infinitely long. We assumed the improvement of noise reduction effect of PERS was indicated through the calculated Leq. Consequently, we have found that the noise reduction effect of drainage asphalt pavement was 5-6 dB, whereas that of PERS was 7-9 dB. 相似文献
995.
K.L. Ishikawa 《Applied physics. B, Lasers and optics》2004,78(7-8):855-858
We simulate the response of He+ exposed simultaneously to fundamental and 27th harmonic pulses from an intense Ti:sapphire laser. High-order harmonic emission from He+ is enhanced by 17 orders of magnitude compared with the case of the fundamental pulse alone. Moreover, while an individual 10 fs laser with a fundamental wavelength of 800 nm and a peak intensity of 3×1014 W/cm2, or its 27th harmonic pulse with a peak intensity of 1013 W/cm2, ionizes no more than 5×10-6 of He+, their combined pulses lead to a surprisingly high He2+ yield of 17%. The underlying mechanism is either harmonic generation from a coherent superposition of states or two-color frequency mixing, depending on the laser wavelength. PACS 32.80.Rm; 42.50.Hz; 42.65.Ky 相似文献
996.
Switching of Single‐Molecule Magnetic Properties of TbIII–Porphyrin Double‐Decker Complexes and Observation of Their Supramolecular Structures on a Carbon Surface
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Tomoko Inose Dr. Daisuke Tanaka Prof. Dr. Hirofumi Tanaka Dr. Oleksandr Ivasenko Prof. Dr. Toshi Nagata Yusuke Ohta Prof. Dr. Steven De Feyter Prof. Dr. Naoto Ishikawa Prof. Dr. Takuji Ogawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(36):11362-11369
Double‐decker complexes based on single‐molecule magnets (SMMs) are a class of highly promising molecules for applications in molecular spintronics, wherein control of both the ligand oxidative states and the 2D supramolecular structure on carbon materials is of great importance. This study focuses on the synthesis and study of 2,3,7,8,12,13,17,18‐octaethylporphyrin (OEP)–TbIII double‐decker complexes with different electronic structures comprising protonated, anionic, and radical forms. Magnetic susceptibility measurements revealed that only the anionic and radical forms of the OEP–TbIII double‐decker complexes exhibited SMM properties. The barrier heights for magnetic moment reversal were estimated to be 207 and 215 cm?1 for the anionic and radical forms, respectively. Scanning tunneling microscopy (STM) investigations revealed that these OEP–TbIII complexes form well‐ordered monolayers upon simple dropcasting from dilute dichloromethane solutions. All three complexes form an isomorphic pseudo‐hexagonal 2D pattern, regardless of the differences in the electronic structures of their porphyrin–Tb cores. This finding is of interest for SMM technology as ultrathin films of these materials undergoing chemical transformations will not require any detrimental reorganization. Finally, we demonstrate self‐assembly of the protonated 5,15‐bisdodecylporphyrin (BDP)–TbIII double‐decker complex as an example of successful supramolecular design to achieve controlled alignment of SMM‐active sites. 相似文献
997.
Daisuke Sawada Yu Ogawa Satoshi Kimura Yoshiharu Nishiyama Paul Langan Masahisa Wada 《Cellulose (London, England)》2014,21(2):1007-1014
Three β-chitin structures [anhydrous, di-hydrate, mono-ethylenediamine (EDA)] recently determined by synchrotron X-ray and neutron fiber diffraction were reviewed from the viewpoint of molecular interactions. Both water and EDA molecules interact with the chitin chains through multiple hydrogen bonds. When water complexes with chitin, the hydrogen bonding pattern rearranges with the replacement of an intrachain chitin hydrogen bond by a stronger hydrogen bond between chitin and water, with an associated reduction in the degrees of freedom; the water oxygen is a much stronger acceptor than the O5 ring atom. The behavior of hydrogen exchange by deuterium supports this interpretation. EDA-molecules change the conformation of hydroxymethyl group from gg to gt, accompanied by changes in hydrogen bonds due to the strong accepting ability of the EDA nitrogen atoms. Some important interactions are in common with experimental crystallographic results of cellulosic crystals and of molecular dynamics studies. These new insights into solid–solvent interactions are valuable in understanding molecular interactions in other polysaccharides-solvents system in solution or on surface. 相似文献
998.
Peter Allen Julia Böttcher Yoshiharu Kohayakawa Yury Person 《Random Structures and Algorithms》2015,46(3):446-465
We give an algorithmic proof for the existence of tight Hamilton cycles in a random r‐uniform hypergraph with edge probability for every . This partly answers a question of Dudek and Frieze (Random Struct Algor 42 (2013), 374–385), who used a second moment method to show that tight Hamilton cycles exist even for where arbitrary slowly, and for . The method we develop for proving our result applies to related problems as well. © 2013 Wiley Periodicals, Inc. Random Struct. Alg., 46, 446–465, 2015 相似文献
999.
Domingos Dellamonica Jr. Yoshiharu Kohayakawa Vojtěch Rödl Andrzej Ruciński 《Random Structures and Algorithms》2015,46(2):274-299
We give a polynomial time randomized algorithm that, on receiving as input a pair (H, G) of n‐vertex graphs, searches for an embedding of H into G. If H has bounded maximum degree and G is suitably dense and pseudorandom, then the algorithm succeeds with high probability. Our algorithm proves that, for every integer and a large enough constant C = Cd, as , asymptotically almost all graphs with n vertices and at least edges contain as subgraphs all graphs with n vertices and maximum degree at most d. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 2014 相似文献
1000.
Hiroyuki Kojima Chisato Takahata David Lemin Masato Takahashi Takuya Kumamoto Waka Nakanishi Noriyuki Suzuki Tsutomu Ishikawa 《Helvetica chimica acta》2013,96(3):379-388
An aziridinomitosene skeleton, a basic core of mitomycin antibiotics, was straightforwardly prepared from N‐(p‐toluenesulfonyl)indole‐2‐carboxaldehyde in 16% overall yield by successive reactions of guanidinium ylide‐mediated aziridination, InCl3‐catalyzed epimerization of trans‐3‐(indol‐2‐yl)aziridine‐2‐carboxylate, leading to the cis‐derivative, and dehydrative cyclization. 相似文献