Search Results 1-20 of 3815

  • Basic Study on Improvement of Spectral Resolution using Subbin Frequency Structure  [in Japanese]

    木村 勇稀 , 増田 純平 , 小坂 哲夫 , 西舘 泉 , 佐藤 学

    電気学会研究会資料. OQD = The papers of technical meeting on optical and quantum devices, IEE Japan 2021(1-6・8), 1-6, 2021-03-15

  • Precision Improvement of Time-frequency Analysis and Application to Development of Audio-MIDI Conversion Tool  [in Japanese]

    茂出木 敏雄

    MIDI カラオケなどの自動演奏データを作成する用途や、耳コピーの自動化や自動採譜の用途において、オーディオ信号をMIDI 形式に変換するツールの実現が要望される。前者においては、MIDI のベロシティやピッチベンドを認識して生演奏に近い演奏表現が求められるのに対し、後者においては、演奏上のテンポやピッチのゆらぎを除去して元の譜面に近い音符表現が求められる。いずれの場合においても、与えられたオーデ …

    尚美学園大学芸術情報研究 = Journal of informatics for arts, Shobi University (33), 51-70, 2021-01

    IR 

  • Characteristics of Multiple-reflection Laser Microphone for Spherical Sound wave Detection

    Mizushima Daisuke , Ohba Tatsuya , Goshima Keishiro , Tsuda Norio , Yamada Jun

    … Because the laser beam works as the detection parts of the laser microphone, it has the wide and flat frequency response and the detectability under the high electromagnetic field. … Single-reflection laser microphones are unable to detect spherical sound waves from a point source because of their low spatial resolution. … It was found that the frequency response of the multiple-reflection laser microphone is affected by the size of the detection area. …

    IEEJ Transactions on Electronics, Information and Systems 141(4), 586-591, 2021

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  • TIME-FREQUENCY ANALYSIS AND DECAY PROPERTIES OF TSUNAMIS

    IZUMIYA Takashi

    … <p> Wigner and Choi-Williams distributions produce increased time-frequency resolution and are applied to obtain the time-frequency distributions for tsunamis. … The Choi-Williams distribution, which suppresses the cross terms, was applied to estimate the time-frequency distributions for tsunamis. …

    Journal of JSCE 9(1), 113-124, 2021

    J-STAGE 

  • µm-class Control of Relative Position and Attitude for a Formation Flying Synthetic Aperture Telescope with Micro-satellites

    SUZUMOTO Ryo , IKARI Satoshi , MIYAMURA Norihide , NAKASUKA Shinichi

    … <p>Earth remote sensing from geostationary orbit (GEO) can realize high temporal resolution; … however, the spatial resolution is commonly worse than observation from low Earth orbit. … In order to achieve high-frequency and high-resolution GEO remote sensing, a "Formation Flying Synthetic Aperture Telescope (FFSAT)" with multiple micro-satellites has been proposed. …

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES 64(2), 101-111, 2021

    J-STAGE 

  • Integrating PWM Amplifier with the Design of Mechatronic Systems for Energy-efficient Precision Motion

    Ito Shingo , Pirker Stefan , Schitter Georg

    … Switching current amplifiers are desirable for high energy efficiency with a concern that the resulting current ripple impairs the achievable positioning resolution. … For this purpose, pulse width modulation (PWM) is used in the current amplifier such that the switching frequency is accurately tuned to the antiresonant frequency. …

    IEEJ Journal of Industry Applications 10(2), 134-141, 2021

    J-STAGE 

  • Formant estimation from speech signal using the magnitude spectrum modified with group delay spectrum

    Chowdhury Husne Ara , Rahman Mohammad Shahidur

    … The traditional magnitude spectrum suffers from difficulties when estimating vocal tract characteristics, particularly for high-pitched speech owing to its low resolution and high spectral leakage. … After phase domain analysis, it is observed that the GD spectrum has low spectral leakage and high resolution for its additive property. …

    Acoustical Science and Technology 42(2), 93-102, 2021

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  • High Resolution Doppler Imaging for Stepped Multiple Frequency Rader  [in Japanese]

    Watanabe Kazuhiro , Inaba Takayuki , Akita Manabu

    … <p>This paper describes a method that can realize high resolution range-Doppler imaging for the front and lateral direction of an on-vehicle radar. … A Doppler shift compensation method for millimeter wave radar using stepped multiple frequency has been proposed. … This method can compensate the spread of Doppler frequency due to multiple frequency transmission, range walk and Doppler walk caused by movement of the radar in a measuring period. …

    IEEJ Transactions on Electronics, Information and Systems 141(3), 453-463, 2021

    J-STAGE 

  • A comparison of modified periodogram and Blackman-Tucky methods for wideband receiver applications

    Pennington Jason , Cheng Chi-Hao

    … This study finds that the modified periodogram can better enable a receiver to detect multiple signals with a significant power difference at the expense of reduced frequency resolution and sensitivity.</p> …

    IEICE Electronics Express 18(4), 20200453-20200453, 2021

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  • Common mode disturbance tolerant broadband differential SPDT switch for Ka-band radar

    Kumar Vijay , Govindarajan Sai Saravanan , Selvaraja Shankar Kumar

    … As a result, this SPDT switch will help in improving radar range due to its high <i>P</i><sub>-1<i>dB</i></sub>, high range-resolution and accuracy due to its broad-bandwidth. … Measurement results of fabricated differential SPDT switch with conventional layout has demonstrated a minimum insertion loss of 2.9 dB and an isolation of -39 dB in 25 GHz to 40 GHz frequency-band, and input P<sub>-1<i>dB</i></sub> …

    IEICE Electronics Express 18(4), 20200428-20200428, 2021

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  • Pilot De-contamination by Modified HTRCI with Time-Domain CSI Separation for Two-cell MIMO Downlink

    MATSUBARA Kakeru , KUROKI Shun , ITO Koki , SHIMADA Kazushi , MARUTA Kazuki , AHN Chang-Jun

    … <p>This letter expands the previously proposed High Time Resolution Carrier Interferometry (HTRCI) to estimate a larger amount of channel status information (CSI). … In order to utilize such null pilot subcarriers for increasing estimable CSI, they should generally be separated in frequency-domain prior to estimation and interpolation processes. …

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, 2021

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  • Spontaneous resolution of refractory ascites in the late phase after cord blood transplantation in acute myeloid leukemia  [in Japanese]

    KAWAMURA Toshikuni , KOBAYASHI Shinichi , KIMURA Fumihiko , TERAMOTO Masahiro , SONE Takehiro , TAKADA Kohei , OGATA Hiraku , SAITO Keita , IZUMI Takuya , OKADA Yosuke , TACHI Noriaki

    <p>同種移植後3ヶ月以降に発症する移植後後期腹水症例は予後不良とされている。我々は臍帯血移植後に難治性腹水症を発症し,腹水発症から約1年半後に腹水が自然軽快した生存例を経験した。症例は61歳,男性。難治性急性骨髄性白血病に対して臍帯血移植を行い,移植後約3ヶ月頃に漏出性腹水が出現した。症状が強いため,毎週腹腔穿刺が必要となった。腹水の原因として血液検査から肝の線維化が示唆された。症状 …

    Rinsho Ketsueki 62(1), 20-24, 2021

    J-STAGE 

  • Direction-of-Arrival Estimation Based on Time-Modulated Coprime Arrays

    MA Yue , MIAO Chen , LI Yuehua , WU Wen

    … Such a time-modulated coprime array (TMCA) is obtained by exchanging a coprime array's phase shifter for a radio frequency (RF) switch. … Compared with a traditional coprime array, the TMCA's structure is much simpler, and it has a higher degree of freedom and resolution compared with a time-modulated uniform linear array (TMULA) due to its exploitation of the virtual array's equivalent signals. …

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E104.A(2), 572-575, 2021

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  • Early Vascular Response to Ultrathin Biodegradable Polymer Sirolimus-Eluting Stents for the Treatment of ST-Elevation Myocardial Infarction After Plaque Rupture

    Oishi Yosuke , Tsukamoto Shigeto , Matsumoto Hidenari , Mori Hiroyoshi , Arai Ken , Nomura Kosuke , Sato Syunya , Yamamoto Myong Hwa , Kosaki Ryota , Wakabayashi Kohei , Sakai Rikuo , Tsujita Hiroaki , Arai Taito , Suzuki Hiroshi , Ochiai Masahiko , Shinke Toshiro , Ogura Kunihiro , Matsukawa Naoki , Tanaka Hideaki , Masaki Ryota , Sakai Koshiro , Sekimoto Teruo , Kondo Seita

    … However, the early vascular response to BP-SES in these patients has not been investigated so far.</p><p>We examined this response in 20 patients with STEMI caused by plaque rupture using frequency-domain optical coherence tomography (OCT) to understand the underlying mechanisms. … = 0.004).</p><p>This study on the early vascular responses following BP-SES implantation showed rapid resolution of atherothrombotic material and progression of strut apposition and coverage.</p><p> …

    International Heart Journal 62(1), 42-49, 2021

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  • Relationship between resolution and partial volume effect among μCT, MDCT and SDCT

    MANO Teppei , HASHIMOTO Shigehiro , MACHIDA Masafumi , KIRIYAMA Yoshimori

    … <p>Partial volume effect is defined as the loss of accuracy for small objects caused by the low resolution of an imaging system. … With low resolution computed tomography (CT), the trabecular bone and cavity are mixed and the brightness representing each of the spaces is averaged. …

    Journal of Biomechanical Science and Engineering, 2021

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  • Sound radiated from low Mach number turbulent boundary layer flows(Turbulent boundary layer on a smooth plate and over a small forward facing step)

    MORIYAMA Shiko , INOUE Yohei , MAEKAWA Hiroshi

    … <p>High-resolution numerical simulation has been performed to study aeroacoustic noise radiated from a turbulent boundary layer at freestream Mach number Ma = 0.3, which develops on a smooth flat plate and over a small forward-facing step. … Sound waves radiated from the turbulent boundary layer on the flat plate are dominant in a very-low-frequency band and have characteristics of a linear sound source. …

    Journal of Fluid Science and Technology 16(2), JFST0010-JFST0010, 2021

    J-STAGE 

  • Evaluation of cone-beam computed tomography over a small field of view in a water bath based on the modulation transfer function with repeating-edge oversampling

    Ito Motohiro , Hayashi Yusuke , Matsumoto Kunihito , Arai Yoshinori , Honda Kazuya

    … The spatial resolution of cone-beam computed tomography (CBCT) in small fields of view (FOVs) is important for clinical applications. … However, it is difficult to measure spatial resolution reliably due to error factors such as noise. … Furthermore, a low-pass filter (LPF) was applied to eliminate the component at frequencies above the Nyquist frequency. …

    Journal of Oral Science 63(1), 87-91, 2021

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  • A study of the pulse-frequency-modulation type image sensor to improve resolution and dynamic range  [in Japanese]

    中原 駿介 , 稲垣 雄志 , 松谷 康之

    電気学会研究会資料. ECT = The papers of technical meeting on electronic circuits, IEE Japan 2020(75-101), 35-38, 2020-12-17

  • Coral-spawn slicks : Reflectance spectra and detection using optical satellite data

    Yamano Hiroya , Sakuma Asahi , Harii Saki

    … This detection was attributable to both their high spatial resolution (3.7 m and 10 m, respectively) and high temporal resolution (1 day and 5 days, respectively), given that coral spawning occurs within a short period (up to several days), typically once a year, and that the coral-spawn slicks have narrow widths of ~10 m. …

    Remote Sensing of Environment (251), 2020-12-15

    IR 

  • Volatile Gas Sensing through Terahertz Pipe Waveguide

    游 博文 , Ja-Yu LU , Borwen YOU , Jiun-You WANG , Sheng-Syong JHUO , Tun-Yao HUNG , Ching-Ping YU

    … The most sensitive THz frequency of the pipe waveguide can recognize vapors with a resolution at a low part-per-million level. …

    Sensors 20(21), 6268-6268, 2020-11-03

    IR 

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