T.Ishizuka, K.Okubo, "Formulation and examination of the perfectly matched layer for sound field analyses using the constrained interpolation profile method", Acoust. Sci. Technol., vol.34, no. 5, pp.378–381, Sep. 2013
K.Nii, N.Tagawa, K.Okubo, and S.Yagi, "Finite Element Method Study for Generating Shear Wave by Mode Conversion of Longitudinal Wave at Elasticity Boundary in a Living Body", Jpn. J. Appl. Phys., vol.52, 07HF01, July, 2013
T.Ishii, T.Tsuchiya, and K.Okubo, "Three-Dimensional Sound Field Analysis Using Compact Explicit-Finite Difference Time Domain Method with Graphics Processing Unit Cluster System", Jpn. J. Appl. Phys., 52, 07HC11, July, 2013
J.Adachi, K.Okubo, N.Tagawa, T.Tsuchiya, and T.Ishizuka, "Examination of Absorbing Boundary Condition Using Perfectly Matched Layer for Collocated Orthogonal Grid in Method of Characteristics", Jpn, J. Appl. Phys., 52, 07HG05, July, 2013
T.Hiraoka, N.Tagawa, K.Okubo, and I.Akiyama, "A Method for Reduction of Frequency Dependent Attenuation in Tissue Harmonic Imaging", 34th Symp. Ultrason. Electron., vol.34, no. 1P2-11, pp.57–58, Nov. 2013
H.Suzuki, N.Tagawa, and K. Okubo, "Ultrasound Speckle Reduction by Randomly Changing Bandwidth of Transmission", 34th Symp. Ultrason. Electron., vol.34, no. 3P5-4, pp.497–498, Nov. 2013
Y.Katori, K.Okubo, T.Hato, A.Tsukamoto, K.Tanabe, N.Onishi, C.Furukawa, S.Isogami, and N.Takeuchi, (Solicited paper)”Development of High Temperature Superconductor Based SQUID (HTS-SQUID) Magnetometer System for Super-sensitive Observation of Geomagnetic Field Changes,” EGU Gen. Assem., vol.EGU2013-86, Apr. 2013.
T.Kawakami, K.Okubo, N.Uchida, N.Takeuchi, and T.Matsuzawa, ”High-Speed Digital Signal Processing Method for Detection of Repeating Earthquakes Using GPGPU-Acceleration,” EGU Gen. Assem., vol.EGU2013-69, Apr. 2013.
N.Kawada, K.Okubo, N.Tagawa and T.Tsuchiya, ”GPU Computing-Based High-Speed Visualization Techniques for Numerical Simulation of Sound Wave Propagation,” 32nd Int. Acoust. Imaging Symp., Apr. 2013.
K.Kawashima, K.Okubo, T.Oshima, and N.Takeuchi, ”A fundamental study on numerical analysis of extremely low frequency sound waves induced by tsunami,” 32nd Int. Acoust. Imaging Symp., Apr. 2013.
H.Suzuki, N.Tagawa, K.Okubo, ”A Study on Ultrasound Speckle Reduction Based on Stochastic Fluctuation of Transmitted Ultrasound Beam,” IEEE Int. Ultrason. Symp., pp.910–913, Jul. 2013.
H.Hiraoka, N.Tagawa, K.Okubo, and I.Akiyama, ”Recursive Reduction of Frequency Dependent Attenuation for Wide-Band Ultrasound Imaging in a Living Body,” IEEE Int. Ultrason. Symp., pp.914–917, Jul. 2013.
O.Tokita, K.Okubo, and N.Tagawa, ”Sub-pixel Precision Image Matching Using Fourier Phase Correlation with Pseudo Spectral Hermite Interpolation (PS-HI) Method,” Int. Work. Adv. Image Technol., Jan. 2014.
J.Fujikawa, N.Tagawa, K.Okubo, and Y.Ho, ”Reflectance Distribution Estimation in a Human Body using Ultrasonic Echoes and Statistical Model,” Int. Forum Ultrasound Appl., Mar. 2014.