研究者業績

宇佐美 尚人

ウサミ ナオト  (Naoto Usami)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 宇宙機応用工学研究系 助教

J-GLOBAL ID
201801018289126150
researchmap会員ID
B000325823

主要な論文

 20
  • Naoto Usami, Etsuko Ota, Akio Higo, Takeshi Momose, Yoshio Mita
    IEEE Transactions on Semiconductor Manufacturing 34(3) 270-277 2021年  査読有り筆頭著者責任著者
  • Naoto Usami, Arnab Muhuri, Avik Bhattacharya, Akira Hirose
    IEEE GEOSCIENCE AND REMOTE SENSING LETTERS 13(12) 2029-2033 2016年12月  査読有り筆頭著者
    Polarimetric synthetic aperture radar is expected to distinguish wet snow from bare ground. However, since both of them show surface scattering, which is sensitive to incidence angle, it often fails in the distinction in mountainous areas. In this letter, we propose an adaptive distinction method using quaternion neural networks. In the ALOS-2 data, we find a monotonic and nonlinear dependence of the degree of polarization on the incidence angle. Then, we feed multiple-incidence-angle teacher information in the learning process. The distinction results of the proposal present higher accuracy than those of the conventional Wishart distinction and a quaternion neural network without the incidence angle information.

講演・口頭発表等

 64
  • 肥後 昭男, 王 海濱, 久保 貴哉, 瀬川 浩司, 杉山 正和, 宇佐美 尚人, 岡本 有貴, 山田 健太郎, 三田 吉郎
    「センサ・マイクロマシンと応用システム」シンポジウム論文集 電気学会センサ・マイクロマシン部門 [編] 2017年10月31日 Institute of Electrical Engineers of Japan
  • 竹城雄大, 宇佐美尚人, 池野理門, 浅田邦博, 三田吉郎, 高田武晃, 鷲津信栄
    センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 2017年10月24日
  • 肥後昭男, WANG Haibin, 久保貴哉, 瀬川浩司, 杉山正和, 宇佐美尚人, 岡本有貴, 山田健太郎, 三田吉郎
    センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 2017年10月24日
  • Akio Higo, Haibin Wang, Takaya Kubo, Naoto Usami, Yuki Okamoto, Kentaro Yamada, Hiroshi Hegawa, Masakazu Sugiyama, Yoshio Mita
    International Conference on Optical MEMS and Nanophotonics 2017年9月26日 IEEE Computer Society
    Imaging devices for near-infrared wavelengths on silicon large scale integration (LSI) are very attractive for secure applications. We here demonstrate an LSI-compatible hybrid IR detector by integrating PbS quantum dots the surface of silicon.
  • 肥後昭男, WANG Haibin, 久保貴哉, 宇佐美尚人, 岡本有貴, 山田健太郎, 瀬川浩司, 杉山正和, 三田吉郎
    電子情報通信学会技術研究報告 2017年8月2日
  • Akio Higo, Haibin Wang, Takaya Kubo, Naoto Usami, Yuki Okamoto, Kentaro Yamada, Hiroshi Hegawa, Masakazu Sugiyama, Yoshio Mita
    2017 INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS (OMN) 2017年 IEEE
    Imaging devices for near-infrared wavelengths on silicon large scale integration (LSI) are very attractive for secure applications. We here demonstrate an LSI-compatible hybrid IR detector by integrating PbS quantum dots the surface of silicon.
  • Naoto Usami, Jun Kinoshita, Rimon Ikeno, Yuki Okamoto, Masaaki Tanno, Kunihiro Asada, Yoshio Mita
    2017 INTERNATIONAL CONFERENCE OF MICROELECTRONIC TEST STRUCTURES (ICMTS) 2017年 IEEE
    We propose an arrayed test structure to assess the damages of metal-oxide-semiconductor field-effect transistors (MOSFETs) exposed under back-side LSI processes, such as by Focused Ion Beam (FIB). Back-side process with FIB is becoming essential to analyze and repair modern LSI chips, to avoid processing through many metal layers with dense wiring and dummy patterns. To access transistors from back-side, however, FET active region must be cropped out and that may cause damage to transistor characteristics. Our test structure consists of 2-D-arrayed MOSFETs. The impact by the back-side process on various conditions can be visualized as I-V characteristics change. The test structure was used with several FIB back-side processes and visualized the damages as threshold shift. The measurement indicated the importance of mixture of fast-and-isotropic etching and slow-and-anistoropic etching to miminimize electrical damage.
  • 衣川 和尭, 宇佐美 尚人, 尚 方, 廣瀬 明
    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報 2016年3月22日 電子情報通信学会
  • 衣川和尭, 宇佐美尚人, SHANG Fang, 廣瀬明
    電子情報通信学会技術研究報告 2016年3月15日
  • Naoto Usami, Amab Muhuri, Avik Bhattacharya, Akira Hirose
    2016 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM (IGARSS) 2016年 IEEE
    In this paper, we propose an effective wet snow mapping method with focus on the incident angle of microwave. Surface scattering is dominant for both wet snow and bare ground. However, it is expected that the characteristic of the wet snow scattering is different from the bare ground one according to the variation of dielectric constant. At the same time, surface scattering characteristics, especially depolarization, also depend on the incident angle. First, we evaluate numerically the degree of polarization of horizontal incident wave as an example with a simplified integral equation model (IEM). We also examine real data of full polarimetric synthetic aperture radar (PoISAR). The results shows that the degree of polarization depends on the difference of incident angles rather that of dielectric constants. Then we conduct wet-snow mapping by supervised learning with teacher areas for large / small incident angles and snow / bare ground. The mapping result agrees well with the estimation by optical data. It is found important to take into account the incident angle in snow mapping.
  • Kazutaka Kinugawa, Fang Shang, Naoto Usami, Akira Hirose
    2016 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM (IGARSS) 2016年 IEEE
    Previously, we have proposed a successful land classification method using a quaternion neural network (QNN) to process parameters based on Stokes vector representation. In this method. the activation function used in the QNN is anisotropic and is applied to input quaternions of which elements are separately and independently processed. In this paper, considering the isotropy of Poincare-sphere space, we propose a new isotropic activation function. Experimental results show that the QNN with the proposed activation function achieves more accurate land classification.
  • 宇佐美尚人, 廣瀬明
    電気学会電磁界理論研究会資料 2014年5月24日
  • Naoto Usami, Akira Hirose
    2014 Asia-Pacific Microwave Conference Proceedings, APMC 2014 2014年3月25日 Institute of Electrical and Electronics Engineers Inc.
    Reconfigurable circular-polarized antennas are expected to improve ground penetrating radars (GPRs) utilizing high-density arrayed and complexly switched antennas. This report presents a wideband reconfigurable circular-polarized single-feed antenna. It comprises a waveguide and a T-shaped probe. We switch its polarization type by changing the bias state of two PIN diodes on the T-probe. Simulation results show that the 3-dB axial ratio bandwidth of the proposed antenna is 29% at 7.5GHz center frequency. The results also show that the main-polarized beam width is 70 degree in the 3-dB axial ratio bandwidth.
  • Naoto Usami, Akira Hirose
    2014 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC) 2014年 IEEE
    Reconfigurable circular-polarized antennas are expected to improve ground penetrating radars (GPRs) utilizing high-density arrayed and complexly switched antennas. This report presents a wideband reconfigurable circular-polarized single-feed antenna. It comprises a waveguide and a T-shaped probe. We switch its polarization type by changing the bias state of two PIN diodes on the "f-probe. Simulation results show that the 3-dB axial ratio bandwidth of the proposed antenna is 29% at 7.5GHz center frequency. The results also show that the main-polarized beam width is 70 degree in the 3-dB axial ratio bandwidth.

担当経験のある科目(授業)

 1

共同研究・競争的資金等の研究課題

 3

その他

 1