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Ando A.,NHK Science and Technical Research Laboratories
Acoustical Science and Technology | Year: 2012

A coding and transmission method for three-dimensional (3D) sound was investigated to realize the broadcasting of 22.2 multichannel sound, which is the audio part of Super Hi-vision. The proposed method was evaluated by performing experiments using the 22-channel signal of 22.2 multichannel sound without two low-frequency effect channels. The loudspeaker positions of the eight-channel system were set as (30,0), (90,0), (150,0), (210,0), (330,0), (60,45), (120,45) and (90, -30). 14 directional functions were used, whose principal axes were directed to (0,0), (30,0), (60,0), (90,0), (120,0), (150,0), (180,0), (270,0), (45,45), (90,45), (135,45), (215,45) (335,45) and (0,90) in degrees. In the experiment, nine sound materials of about 10 s length were used. One of the materials was used for training W s. The number of iterations in the simulated annealing was set to 10,000. For sound materials other than Birds, a significant power reduction was obtained, suggesting that the spatial characteristics of 3D sound can be learnable. Source

Suna Y.,Tokyo Institute of Technology | Nishida J.-I.,Tokyo Institute of Technology | Fujisaki Y.,NHK Science and Technical Research Laboratories | Yamashita Y.,Tokyo Institute of Technology
Organic Letters | Year: 2012

Organic field-effect transistors with hydrogen-bonded diketopyrrolopyrrole- thiophene co-oligomers were fabricated by a solution-process method with annealing at 200 °C, showing ambipolar charge-carrier transfer with field-effect mobilities up to μ h = 6.7 × 10 -3 cm 2 V -1s -1 and μ e = 5.6 × 10 -3 cm 2 V -1 s -1. © 2012 American Chemical Society. Source

Masaoka K.,NHK Science and Technical Research Laboratories
Optics Letters | Year: 2010

A fast and accurate model to compute optimal colors under a given illuminant is introduced. The model estimates the reflectance (transmittance) distributions of optimal colors, which is bandpass (Type 1) or bandstop (Type 2), at a given luminance factor with user-specified small tolerances for the bandwidth (e.g., 10-10 nm). The tristimulus values of the optimal colors are obtained by using trapezoidal integration of the product of color-matching functions and illuminant spectrums sampled with small wavelength steps instead of performing summation of the product values. Selecting the distribution type whether Type 1 or Type 2 is avoided in the algorithm to reduce computing cost. Some optimal color solids computed by a MATLAB program have been demonstrated. © 2010 Optical Society of America. Source

Kumaki D.,Yamagata University | Fujisaki Y.,NHK Science and Technical Research Laboratories | Tokito S.,Yamagata University
Organic Electronics: physics, materials, applications | Year: 2013

We report on a newly developed solution process using MoO3 for reducing source and drain (S/D) electrodes in organic thin-film transistor (TFT). By taking advantage of the difference in surface wettability between the gate dielectric layer and the S/D electrodes, the electrode treatment using the MoOx solution was applied to polymer TFT with short channel lengths less than 10 μm. The contact resistance was noticeably reduced at the interface of the S/D electrodes in a polymer TFT using a pBTTT-C16. Furthermore, the field effect mobility for this TFT was enhanced from 0.03 to 0.1 cm 2/V s. Most notably, the threshold voltage (Vth) shift under gated bias stress was less than 0.2 V after 105 s, which is comparable to that of conventional poly crystalline Si TFT. © 2012 Elsevier B.V. All rights reserved. Source

Ando A.,NHK Science and Technical Research Laboratories
IEEE Transactions on Audio, Speech and Language Processing | Year: 2011

In this paper, we describe a new method for converting the signal of the original multichannel sound system into that of an alternative system with a different number of channels while maintaining the physical properties of sound at the listening point in the reproduced sound field. Such a conversion problem can be described by the underdetermined linear equation. To obtain an analytical solution to the equation, the method partitions the sound field of the alternative system on the basis of the positions of three loudspeakers and solves the local solution in each subfield. As a result, the alternative system localizes each channel signal of the original sound system at the corresponding loudspeaker position as a phantom source. The composition of the local solutions introduces the global solution, that is, the analytical solution to the conversion problem. 22-channel signals of a 22.2 multichannel sound system without the two low-frequency effect channels were converted into 10-, 8-, and 6-channel signals by the method. Subjective evaluations showed that the proposed method could reproduce the spatial impression of the original 22-channel sound with eight loudspeakers. © 2011 IEEE. Source

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