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101.
102.
There are many approaches to achieving high-performance speech enhancement. The modeling of the human auditory system is a good approach, since human beings can focus on target speech under concurrent speech conditions. One example of the binaural models is the time domain binaural model. However, this model has a high-calculation cost because the algorithm is based on auto-correlation, which is computationally intensive. Another example is the frequency domain binaural model proposed by Nakashima et al. [Nakashima H, Chisaki Y, Usagawa T, Ebata M. Frequency domain binaural model based on interaural phase and level differences. Acoust Sci Technol 2003;24(4):172-8]. Since the frequency domain binaural model uses the fast fourier transform, the calculation cost is much lower than that of the time domain binaural model. Therefore, it is not difficult to perform real-time processing using recent hardware such as digital signal processors and even laptop personal computers. However the quality of the segregated sound obtained using the frequency domain binaural model depends on system parameters such as frequency resolution and frame shift length for overlap adding in time domain. This paper introduces the construction of a prototype of a hearing assistant system based on the frequency domain binaural model. The detailed implementation techniques and parameter tuning are mentioned. The proposed system runs in real-time after parameter tuning. The directional attenuation levels, that is, the directivity patterns of the proposed system is measured. Finally, it is shown that the prototype can extract sounds coming from specific directions in real-time. 相似文献
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105.
Determination of overt carnitine palmitoyltransferase by reversed-phase high-performance liquid chromatography 总被引:1,自引:0,他引:1
A method for the determination of carnitine palmitoyltransferase I (CPT I; EC 2.3.1.19) in isolated rat liver mitochondria by reversed-phase high-performance liquid chromatography is described. Enzyme activity is assayed by direct determination of coenzyme A (CoA) released from palmitoyl-CoA within 60 min by a linear gradient system. CPT 1 in rat liver mitochondria can be assayed from only 30 micrograms of mitochondrial protein per millilitre of assay mixture. The changes in the kinetic parameters of CPT I, including Ki for malonyl-CoA, resulting from the fasting-feeding cycle are also discussed. 相似文献
106.
Kobayashi M Matsuo T Fukunaga T Hashizume D Fueno H Tanaka K Tamao K 《Journal of the American Chemical Society》2010,132(43):15162-15163
π-Conjugated disilenes with 2-naphthyl or 2-fluorenyl groups on the silicon atoms have been synthesized as air-stable emissive red solids using the bulky 1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl (Eind) groups. The strong π-π* absorptions and distinct emission at room temperature, both in solution and in the solid state, have been observed due to the substantial contribution of the 3p(π)*(Si-Si)-2p(π)*(carbon π-electron system) conjugation. 相似文献
107.
Ru Chen Yuezhen Bin Yumiko Nakano Naoko Kurata Masaru Matsuo 《Colloid and polymer science》2010,288(3):307-316
In an attempt to improve the mechanical property of polyethylene composite at high temperature, crosslinking of ultrahigh-molecular-weight
polyethylene (UHMWPE) and carbon fiber (CF) blends was carried out by using dicumyl peroxide (DCP). The specimens were prepared
by gelation/crystallization from solutions. The effect of chemical crosslinking on mechanical and electrical properties of
UHMWPE/CF blends with composition of 1/0, 1/0.25, and 1/1 (w/w) were investigated in detail. Electrical conductivity and thermal mechanical properties of the blends with the 1/1 composition
were greatly improved by incorporation of enough content of CF and adequate crosslinking network formation. Surprisingly,
the Young’s modulus of the 1/1 blend reached 20 GPa at room temperature (20 °C). On the other hand, heat treatment at 135 °C
played an important role for obtaining a high PTC effect for the UHMWPE-CF blend in which the PTC intensity reached 107. 相似文献
108.
Dianions of dimetallic hexa(organo)[70]fullerene [(C5R5)2Ru2C70Ar6]2? (R=H, Me; Ar=Ph, 4‐MeC6H4, 4‐tBuC6H4) react with benzylic bromide to yield the dibenzylated product dimetallic octa(organo)[70]fullerene (C5R5)2Ru2C70Ar6(CH2Ar′)2 (Ar′=Ph, 4‐MeO2CC6H4), where the benzylic groups are attached to the equatorial belt region of [70]fullerene; this region is generally considered to be rather unreactive. This unusual structure was unambiguously determined by X‐ray crystallography. Theoretical studies on the electronic properties of the monoanionic intermediate indicated that the highest spin density resides on the two carbon atoms in the belt region; one of them then couples with a benzylic radical to yield the octa(organo)fullerene product after ionic substitution of the fullerene anion with a benzylic bromide. Electrochemical analysis of the hexa(organo) and octa(organo) ruthenium complexes suggests that the modification of the belt region does not affect the electronic communication between the two metal centers. 相似文献
109.
Jing-Kun Fang De-Lie An Kan Wakamatsu Tetsuo Iwanaga Daisuke Matsuo Junzo Otera 《Tetrahedron letters》2010,51(6):917-6811
A series of diphenylamino-substituted phenylene-(poly)ethynylenes were successfully synthesized by a combination of Sonogashira coupling and double elimination protocol of β-substituted sulfones. When UV-light was irradiated, the amino-substituted phenylene-(poly)ethynylene emitted strong luminescence. The emission underwent a large bathochromic shift in polar solvent because of stabilization of their charge-separated excited states. Analyses of fluorescence life times of aminoacetylenes revealed that radiationless process was suppressed in the polar solvent CH2Cl2, resulting in high quantum yields. 相似文献
110.
S Matsuo N Sakaguchi E Obuchi K Nakano R C Perera T Watanabe T Matsuo H Wakita 《Analytical sciences》2001,17(1):149-153
Ni L- and Ti L-edge as well as Ti K-edge X-ray absorption experiments for TiO2 thin films and Ni-doped TiO2 thin films coated on glass plates were performed using synchrotron radiation to investigate the structures around Ni and Ti ions in the films. The obtained spectra were compared with the results of theoretical calculations. It has consequently been found that the spectral features were affected by a change in the oxidizing form of Ni ions due to hydrogen reduction, by the charge variation and/or slight orbital splitting of Ti ions, and by the magnitude of the interaction between the center Ti ion and neighboring Ti ions. 相似文献