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231.
Reconstructing the challenging human face identification process as a stability problem, we show that Electoral College can be used as a framework that provides a significantly enhanced face identification process by improving the accuracy of all holistic algorithms. The results are demonstrated by extensive experiments on benchmark face databases applying the Electoral College framework embedded with standard baseline and newly developed face identification algorithms. 相似文献
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234.
Naoyuki Suzuki Harumasa Takeda Akihiko Ohta Hisasi Ohuchida 《Fatigue & Fracture of Engineering Materials & Structures》1991,14(8):815-821
Abstract— Fatigue crack propagation rates and the fatigue threshold of HT80 steel were measured by maintaining the maximum load during the whole period of random loading in order to prevent fatigue crack closure. The random loading pattern involved 62 level block loadings in which the waveform was approximated to the Rayleigh distribution of peaks. The fatigue crack propagation rates under random loading were well predicted from those obtained from constant amplitude loading and assuming a linear cumulative damage law. That is, da/dn = C {Δ K m eq −Δ K m th } where the equivalent stress intensity factor, Δ K eq ={= n i Δ K m i /d n i }1/ m , where ni = 0 for Δ K i ≤Δ K th , or ni = ni for Δ Ki > Δ K th . 相似文献
235.
Summary High molecular weight poly(methyl alkyl fumarate) were prepared through radical polymerization of methyl alkyl fumarates(MRF) and monomer-isomerization radical polymerization of methyl alkyl maleates(MRM). The polymerization reactivities(yield and viscosity) of MRFs and MRMs were found to increase with increasing of the bulkiness of the ester alkyl substituents, but MRFs showed generally higher reactivities than MRMs. These polymers were also observed to consist of less- or non-flexible rod-like poly(methoxy-carbonylmethylene-alt-alkoxycarbonylmethylene) structure depending on their bulkiness. The MtBF polymer did not melt, which showed somewhat decreased thermal stability.Polymers from 1,2-Disubstituted Ethylenic Monomers. VIII. 相似文献
236.
Tetsuya Iizuka Hideki Sezutsu Ken‐ichiro Tatematsu Isao Kobayashi Naoyuki Yonemura Keiro Uchino Kenichi Nakajima Katsura Kojima Chiyuki Takabayashi Hiroaki Machii Katsushige Yamada Hiroyuki Kurihara Tetsuo Asakura Yasumoto Nakazawa Atsushi Miyawaki Satoshi Karasawa Hatsumi Kobayashi Junji Yamaguchi Nobuo Kuwabara Takashi Nakamura Kei Yoshii Toshiki Tamura 《Advanced functional materials》2013,23(42):5218-5218
237.
Ziyi Zhang Motoki Yako Kan Ju Naoyuki Kawai Papichaya Chaisakul Tai Tsuchizawa 《Science and Technology of Advanced Materials》2013,14(1):283-293
AbstractA new materials group to implement dense wavelength division multiplexing (DWDM) in Si photonics is proposed. A large thermo-optic (TO) coefficient of Si malfunctions multiplexer/demultiplexer (MUX/DEMUX) on a chip under thermal fluctuation, and thus DWDM implementation, has been one of the most challenging targets in Si photonics. The present study specifies an optical materials group for DWDM by a systematic survey of their TO coefficients and refractive indices. The group is classified as mid-index contrast optics (MiDex) materials, and non-stoichiometric silicon nitride (SiNx) is chosen to demonstrate its significant thermal stability. The TO coefficient of non-stoichiometric SiNx is precisely measured in the temperature range 24–76 °C using the SiNx rings prepared by two methods: chemical vapor deposition (CVD) and physical vapor deposition (PVD). The CVD-SiNx ring reveals nearly the same TO coefficient reported for stoichiometric CVD-Si3N4, while the value for the PVD-SiNx ring is slightly higher. Both SiNx rings lock their resonance frequencies within 100 GHz in this temperature range. Since CVD-SiNx needs a high temperature annealing to reduce N–H bond absorption, it is concluded that PVD-SiNx is suited as a MiDex material introduced in the CMOS back-end-of-line. Further stabilization is required, considering the crosstalk between two channels; a ‘silicone’ polymer is employed to compensate for the temperature fluctuation using its negative TO coefficient, called athermalization. This demonstrates that the resonance of these SiNx rings is locked within 50 GHz at the same temperature range in the wavelength range 1460–1620 nm (the so-called S, C, and L bands in optical fiber communication networks). A further survey on the MiDex materials strongly suggests that Al2O3, Ga2O3 Ta2O5, HfO2 and their alloys should provide even more stable platforms for DWDM implementation in MiDex photonics. It is discussed that the MiDex photonics will find various applications such as medical and environmental sensing and in-vehicle data-communication. 相似文献
238.
The effects of preservatives used for glue‐line treatment on the curing of phenol‐formaldehyde resin (PF) were studied by dynamic mechanical analysis and differential scanning calorimetry. Storage modulus, G′, loss modulus, G″, and loss tangent, tan δ, of PF with and without preservatives were recorded as a function of time under isothermal heating. The time required for G′, G″, and tan δ to reach steady values increased with addition of preservative. The G′, G″, and tan δ curves of PF containing benzyl alcohol (used in the preservative as a diluent) were almost identical to those of PF containing preservative. However, the addition of antitermite and anti‐fungal compounds alone had no effect on the curing process. There were no differences in total reaction enthalpy or dependence of activation energy on degree of conversion between pure PF and mixtures. Our results indicate that benzyl alcohol in preservatives plasticizes the curing system for PF. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
239.
Syuji Fujii Motomichi Suzaki Kenichi Sakai Naoyuki Ishida Simon Biggs 《Polymer》2010,51(26):6240-12909
The surface of near-monodisperse colloidal polystyrene (PS) latex particles carrying pH-responsive poly[2-(diethylamino)ethyl methacrylate] (PDEA) polymer chains as a steric stabilizer has been extensively characterized in dry and wet states. X-ray photoelectron spectroscopy and contact angle measurement studies confirm that PDEA chains are located on the PS latex particle surface. Transmission electron microscopy (TEM) studies reveal that the sterically stabilized PS particles have a core-shell morphology and wet atomic force microscopy data confirm that the pH-responsive PDEA component covers the PS latex core and the thickness of the protonated steric polymer is estimated to be approximately 15 nm. The PS latex particles can be easily dispersed in acidic aqueous media (pH 3.0) whilst they flocculate in basic aqueous media (pH 10.0) due to the pH-responsive PDEA hair. This dispersion-flocculation cycle of the PS latex is fully reversible. 相似文献
240.
Rikizo Hatakeyama Naoyuki Sato Noriyoshi Sato 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1992,70(1-4):21-25
A new method for ion-species and isotope separations is described, which is expected to yield higher mass resolution and collection rates than the conventional ion-cyclotron-resonance technique. It is based on the principle that travelling waves with cyclotron frequencies generate charged particle drifts perpendicular to both the direction of wave propagation and external magnetic field lines. 相似文献