Updated on 2024/11/26

 
NAKASHI Kenichi
 
Scopus Paper Info  
Total Paper Count: 0  Total Citation Count: 0  h-index: 4

Citation count denotes the number of citations in papers published for a particular year.

Affiliation
Faculty of Engineering Department of Electrical and Electronic Engineering
Job
Associate Professor
External link

Research Interests

  • Electronic Circuits

Research Areas

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Measurement engineering

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Electron device and electronic equipment

Undergraduate Education

  • 1985.03   Kyushu University   Faculty of Engineering   Electrical Engineering   Graduated   Japan

Post Graduate Education

  • 2002.09   Kyushu University   Doctoral Program   Unfinished Course   Japan

  • 1987.03   Kyushu University   Graduate School, Division of Engineering   Electrical Engineering   Master's Course   Completed   Japan

Degree

  • Kyushu University  -  Doctor of Engineering   1997.07

Biography in Kyutech

  • 2008.04
     

    Kyushu Institute of Technology   Faculty of Engineering   Department of Electrical and Electronic Engineering   Associate Professor  

Biography before Kyutech

  • 2006.10 - 2008.03   ATR   WEL   Japan

  • 2003.04 - 2005.03   Fukuoka Industry, Science & Technology Foundation   Fukuoka Laboratory for Emrging & Enabling Technology of SoC   Researcher   Japan

  • 2002.10 - 2003.03   Kyushu University   Medical Institute of Bioregulation   Japan

  • 2000.04 - 2001.03   University of California at Berkeley   Department of Electrical Engineering and Computer Sciences   Visiting Scholar   United States

  • 1999.04 - 2000.03   Kyushu University   Graduate School of Information Science and Electrical Engineering   Associate Professor (as old post name)   Japan

  • 1997.11 - 1999.03   Kyushu University   Faculty of Engineering   Associate Professor (as old post name)   Japan

  • 1991.03 - 1997.10   Kyushu University   Faculty of Engineering   Research Assistant   Japan

  • 1987.04 - 1991.02   Hitachi Ltd.   Hitachi Research Laboratory, Hitachi Ltd.   Japan

▼display all

Academic Society Memberships

  • 1994.04   IEEE   United States

Research Career

  • Analog Integrated Circuits Design

    Analog Integrated Circuits

    研究期間： 2010.04  - 

  • Reconfigurable Data Converters

    Analog Circuits, ADC, DAC, Reconfigurable

    研究期間： 2008.04  - 

  • Vital signal sensing

    Vital Signal Sensor, System LSI, Analog Circuits

    研究期間： 2007.04  - 

  • Signal Proccesing by Stochastic Resonance

    Signal Proccesing, Stochastic Resonance, Analog Circuits

    研究期間： 2015.04  - 

Papers

  • A Helmet-type Body Temperature and Heart Rate Measurement System for Heat Stroke Prevention Reviewed

    Riku Hironaka, Kenichi Nakashi

    2021 IEEE 10th Global Conference on Consumer Electronics, GCCE 2021 ( Institute of Electrical and Electronics Engineers )   1   974 - 975   2021.10

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    Japan   Kyoto   2021.10.12  -  2021.10.15

    DOI： 10.1109/GCCE53005.2021.9622082

  • Detecting System Alzheimer's Dementia by 1d CNN-LSTM in Japanese Speech Reviewed

    Nishikawa K., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   2021-January   2021.01

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    Dementia patients have increased year by year in many developed countries. We need to solve this problem. The questionnaire method is generally used for present dementia screening. However, this method requires time for 10 to 15 minutes with a doctor and a clinical psychologist, which puts a burden on hospitals and test subjects. For this reason, we propose a detecting method using deep learning by means of 1d CNN-LSTM to construct a dementia discriminant system using speech voice. Our method obtained the Accuracy of 0.908 and the F-measure of 0.897.

    DOI： 10.1109/ICCE50685.2021.9427692

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  • Speech Enhancement System using SVM for Train Announcement Reviewed

    Kinoshita Y., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   2021-January   2021.01

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    On the train, announcement speech is one of the important information to know the operation status. However, clarity of announcement speech is not enough because announcement speech is masked by noise. Therefore, new system is proposed to improve clarity of announcement speech based on sound classification. By classifying several sounds, users can select the announcement speech only they want to hear. In this paper, classifier is developed that distinguishes announcement speech using SVM. In the experiments, this classifier obtain that the accuracy of developed classifier is 96%.

    DOI： 10.1109/ICCE50685.2021.9427600

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  • Eye Fatigue Prediction System Using Blink Detection Based on Eye Image Reviewed

    Kuwahara A., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   2021-January   2021.01

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    Today, information devices such as smartphones have become indispensable in our daily life. As a result, the increased use of information devices has led to the accumulation of eye strain and the development of various eye diseases. As the accumulation of eye-fatigue is manifested in the change in the number of blinks, blink detection technology is necessary. In the previous paper, we proposed a highly accurate blink detection method called EARM. However, there is a problem with this technique, which is that the noise generated by the movement of the face can reduce the accuracy of blink detection. In this study, we used face image normalization to improve the blink detection system by reducing the noise associated with face movement. We found that the proposed system outperformed the results of blink detection accuracy using EARM in all subjects.

    DOI： 10.1109/ICCE50685.2021.9427681

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  • Speaker verification method using htm for security system Reviewed

    Sakaguchi Y., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Advances in Intelligent Systems and Computing   1253 AISC   160 - 165   2021.01

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    In recent years, we have been using biometric verification systems in various places such as daily life and businesses. However, it’s insufficient in hospital and food factory to introduction of the security system of the room access control. This is because they wear gloves, masks and hats in hospitals and factories, so they cannot verify faces or fingerprints. In this study, we propose a speaker verification system using HTM (Hierarchical Temporal Memory). We verify speaker and detection of unlearned speakers by experiments. In addition, we consider the use in hospitals and factories, and also evaluate it in a noisy environment. The evaluation values are Precision, Recall, and F-measure. The experimental results show that in the case of 10 learners, F-measure exceeded 0.6 in the classification of 2 classes of learners and non-learners.

    DOI： 10.1007/978-3-030-55307-4_25

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  • Sitting posture assessment method for back pain prevention system Reviewed

    Joumori D., Hirakawa R., Kawano H., Nakashi K.

    Advances in Intelligent Systems and Computing   1253 AISC   351 - 355   2021.01

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    Back pain is widespread in Japan in recent years. The economic loss from back pain in Japan was 82.1 billion yen in 2011. Therefore, it is necessary to construct a low back pain prevention system that can be easily used. First, system estimate the body part from the image using OPENPOSE. It extract the five coordinates (neck, shoulders, and buttocks) from the output. It calculate the z coordinate of each point. Finally, It estimate the front-back tilt and the left-right tilt. We compare three distances (2 m, 3.5 m, 5 m) and three angles (20°, 0°, −20°) in experiments. Review the results. In the distance, the discrimination rates are 2 m: 83%, 3.5 m: 99%, 5 m: 66%. Next, regarding the angle, the discrimination system was good in the order of 20°, 0°, 20°.

    DOI： 10.1007/978-3-030-55307-4_53

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  • Effective speech features for distinguishing mild dementia patients from healthy person Reviewed

    Nishikawa K., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Advances in Intelligent Systems and Computing   1253 AISC   356 - 361   2021.01

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    The questionnaire method is generally used for present dementia screening. However, this method requires time for 10 to 15 min with a doctor and a clinical psychologist, which puts a burden on hospitals and test subjects. The purpose of this study is to reduce the burden of users by constructing a system to distinguish patients with mild dementia and healthy persons from speech data. Before that this paper examines the effectiveness of speech features. MFCC has been confirmed to be effective in previous research, this paper extracted six kinds of other speech features that are likely to be correlated with symptoms of dementia. This paper got about 90% accuracy rate for a sentence of conversational speech in SVM and Random Forest. Moreover, this paper has calculated the importance of the features by using the SVM-RFE method. As a result, this showed that log-mel spectrum was more important than MFCC.

    DOI： 10.1007/978-3-030-55307-4_54

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  • Blink detection using image processing to predict eye fatigue Reviewed

    Kuwahara A., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Advances in Intelligent Systems and Computing   1253 AISC   362 - 368   2021.01

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    With the use of information terminals represented by smartphones, our eyes get tired. One index indicating eye fatigue is a change in the number of blinks. In this study, we set the ultimate goal that is to develop eye fatigue prevention system with less time and less physical burden for patient. By doing this, the information terminal performs a flickering of the eyes using a detection camera and a validity check. Previous EAR study with blink detection is confirmed to be effective, and this paper proposes a new formula EARM used EAR. As an evaluation method of blink detection, we used the total time average of the square of the residual value. The results showed that EARM was more accurate than the EAR. Further, it was suggested that the number of blinks during VDT work can be classified into several patterns.

    DOI： 10.1007/978-3-030-55307-4_55

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  • On Near-Infrared Optical Properties of Ethanol for a Wearable Blood Alcohol Sensor Reviewed

    Nakashi K., Tanimoto S., Nagayoshi K.

    2020 IEEE 9th Global Conference on Consumer Electronics, GCCE 2020 ( Institute of Electrical and Electronics Engineers )   251 - 253   2020.10

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    Japan   Kobe   2020.10.13  -  2020.10.16

    DOI： 10.1109/GCCE50665.2020.9291911

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  • Study on mistype correction support using attention in Japanese input Reviewed

    Komatsu R., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   2020-January   2020.01

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    © 2020 IEEE. How to input characters without mistakes is one of very important points for the interface, when we consider usability of electronic devices such as personal computers and smartphones. Therefore, in this paper, we examine whether we can classify mistypes for Japanese input and inform the users how they make mistakes using 'Attention' and 'LSTM' of machine learning methods. First, we classified the category of mistypes in Japanese input into seven types (Replacement, Removal, Exchange, Insertion, Involvement, Repetition). Second, we asked subjects to input the displayed words and collected their data. Next, we classified the data and labeled it. Finally, we made the Neural Network (LSTM + Attention) to classify the mistype data and inform how they make mistakes. As a result, the correct answer rate of the Neural Network (LSTM + Attention) was about 70% and we were able to know where point the Neural Network focus on by putting in 'Attention'. We are planning to use 'LSTM' to correct mistype directly and use 'Attention' to inform how they frequently make mistakes in the future.

    DOI： 10.1109/ICCE46568.2020.9043138

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  • Electrolarynx system using voice conversion based on WaveRNN Reviewed

    Urabe E., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   2020-January   2020.01

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    © 2020 IEEE. Voice is very important in our daily life. However, some people cannot speak because of throat surgery. Electrolarynx (EL) is a way for them to speak again but this voice is flat and noisy like a buzzer. Therefore, we propose a new Electrolarynx system based on WaveRNN. When we use it, the EL voice is converted into a voice close to the natural voice. We assume that this system will be provided as a smartphone application. In the experiment, we evaluated the converted voice by the system and found that naturalness improved.

    DOI： 10.1109/ICCE46568.2020.9043135

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  • Discussion on differences in frequency band required for horizontal sound localization by age Reviewed

    Okuno T., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    DOI： 10.1145/3325291.3325395

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  • Study on watching system for door-to-door sales detection and risk determination Reviewed

    Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    DOI： 10.1145/3325291.3325391

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  • Study on method of veering correction by vibration transmission in walking support for visually impaired people Reviewed

    Hirayama T., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    DOI： 10.1145/3325291.3325392

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  • Study on evaluating risks of routes damages at Earthquakes for evacuation guidance system Reviewed

    Mihara Y., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    DOI： 10.1145/3325291.3325390

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  • In load collapse prevention system Examination of the relationship between truck vibration and load inclination Reviewed

    Inoshita C., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    Language：English   Publishing type：Research paper (international conference proceedings)

    DOI： 10.1145/3325291.3325393

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  • Examination of acoustic features for discriminating between real and loudspeaker speeches Reviewed

    Kinoshita Y., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    DOI： 10.1145/3325291.3325394

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  • Enhancement of electrolarynx speech based on WaveRNN Reviewed

    Urabe E., Hirakawa R., Kawano H., Nakashi K., Nakatoh Y.

    ACM International Conference Proceeding Series   2019.05

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    Language：English   Publishing type：Research paper (international conference proceedings)

    DOI： 10.1145/3325291.3325396

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  • Development of a Portable Taste Sensor with a Lipid/Polymer Membrane Reviewed

    Yusuke Tahara, Kenichi Nakashi, Ke Ji, Akihiro Ikeda and Kiyoshi Toko

    Sensors   13 ( 1 )   1076 - 1084   2013.01

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    DOI： 10.3390/s130101076

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  • Taste Sensor Chip for Portable Taste Sensor System Reviewed

    Shinichi Etoh,Lingyan Feng,Kenichi Nakashi,Kenshi Hayashi,Akira Ishii and Kiyoshi Toko

    Sensors and Materials   20 ( 4 )   151 - 160   2008.04

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  • Fabrication of taste sensor chip and portable taste sensor system Reviewed

    Etoh S., Iwakura M., Nakashi K., Hattor R., Hayashi K., Toko K.

    Proceedings of 2006 International Conference on Microtechnologies in Medicine and Biology   180 - 183   2006.12

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    Language：English   Publishing type：Research paper (international conference proceedings)

    DOI： 10.1109/MMB.2006.251522

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  • CMOS system LSI for processing IEEE 802.11B WLAN PHY signals through digital, analog baseband, and RF Reviewed

    Tsujimoto T., Kanaya H., Nakashi K., Okamoto K., Tarumi K., Nakamura T., Takatori H., Hatano K., Tsuchiya T., Yoshida K., Kuroki Y., Yasuura H.

    IEEE Asia-Pacific Conference on Circuits and Systems, Proceedings, APCCAS   1   17 - 20   2004.12

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  • Phase detectors/phase frequency detectors for high performance PLLs Reviewed

    Yoshizawa H., Taniguchi K., Nakashi K.

    Analog Integrated Circuits and Signal Processing   30 ( 3 )   217 - 226   2002.03

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    Language：English   Publishing type：Research paper (international conference proceedings)

    DOI： 10.1023/A:1014428400796

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  • Design of fast lock-in PLL with variable loop parameter control Reviewed

    Hachiyama K., Nakashi K., Yoshizawa H., Taniguchi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   5 ( 1 )   147 - 152   2000.03

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (bulletin of university, research institution)

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  • A PLL with variable loop gain for fast lock-in Reviewed

    Nakashi K., Yoshizawa H., Komeie N., Taniguchi K.

    International Symposium on IC Technology, Systems and Applications   8   263 - 266   1999.12

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    A variable loop gain PLL for fast lock-in is proposed, it changes dynamically the loop gain by altering the charge pump current or the capacitance of LPF according to the frequency difference between input and VCO signals. PLL consists of charge-pump PLL core and loop gain control block which contains FDD (Frequency Difference Detector) and variable-capacitance circuits. The proposed PLL is designed in 0.5μm CMOS and computer simulation shows that its lock-in time is twice faster than that of the conventional PLL.

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  • Design of on-chip clock generation PLL for low jitter and small chip area Reviewed

    Yoshizawa H., Nakashi K., Taniguchi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   4 ( 1 )   93 - 98   1999.03

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  • HEMT device characteristics calculation and modeling based on device structure Reviewed

    Kudou Y., Nakashi K., Taniguchi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   3 ( 1 )   107 - 110   1998.03

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  • Implementation technique of dynamic CMOS circuit applicable to asynchronous/synchronous logic Reviewed

    Yoshizawa H., Taniguchi K., Nakashi K.

    Proceedings - IEEE International Symposium on Circuits and Systems   2   145 - 148   1998.01

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  • A new phase frequency detector with feedforward reset for low supply voltage Reviewed

    Yoshizawa H., Taniguchi K., Nakashi K., Shirahama H.

    International Symposium on IC Technology, Systems and Applications   7   628 - 631   1997.12

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  • RTD/HEMT logic circuits and their functional circuits application Reviewed

    Nakashi K., Taki H., Kudou Y., Taniguchi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   2 ( 1 )   46 - 52   1997.03

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    This paper describes low-power and high-speed RTD/HEMT (Resonant Tunneling Diode / High-Electron Mobility Transistor) logic circuits. In order to estimate RTD/HEMT logic gates using ordinary GaAs/AlGaAs HEMT in detail by using real device parameters extracted from measured values, we have examined their characteristics. Fundamental characteristics of logic gates are examined and compared with resistor-load and depletion-mode HEMT (D-HEMT) load inverters. The results show that RTD/HEMT inverter is the fastest among them. Their application to functional circuits such as phase comparator (PC) and voltage controlled oscillator (VCO) used in PLL are also described.

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  • A phase frequency detector constructed with dynamic CMOS gates for low power PLL Reviewed

    Yoshizawa H., Taniguchi K., Nakashi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   2 ( 1 )   53 - 58   1997.03

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    Language：English   Publishing type：Research paper (bulletin of university, research institution)

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  • A low power 622 MHz CMOS phase-locked loop with source coupled VCO and dynamic PFD Reviewed

    Yoshizawa H., Taniguchi K., Shirahama H., Nakashi K.

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   E80-A ( 6 )   1015 - 1020   1997.01

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  • A design of first-order delay-line DPLL in 1.2μm CMOS technology Reviewed

    Seki I., Nakashi K., Ushida M., Taniguchi K.

    Research Reports on Information Science and Electrical Engineering of Kyushu University   1 ( 1 )   45 - 50   1996.09

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    Authorship：Corresponding author   Language：English   Publishing type：Research paper (bulletin of university, research institution)

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  • A new very fast pull‐in phase‐locked loop with antipseudo‐lock function Reviewed

    Shirahama H., Taniguchi K., Nakashi K.

    Electronics and Communications in Japan (Part II: Electronics)   78 ( 12 )   104 - 114   1995.12

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    With the development of high‐speed digital communications, e.g., optical fiber communications, smaller, faster, retiming devices are being required. The phase‐locked loops (PLLs) are suited to an integration compared to surface acoustic wave (SAW) or liquid crystal (LC) passive filters. Therefore, PLLs have been put to use gradually as clock extraction devices in any frequency range over 100 MHz. The authors have developed the previously reported PLL with frequency difference detector (FDD) to provide a new function, which is useful to overcome the pseudo‐lock problem in conventional retiming PLLs and also improved performance of the FDD. The proposed PLL has been constructed with ECL‐IC, PLA and other discrete parts. It has been evaluated experimentally and the PLL designed with a 0.8‐μ design‐rule bipolar transistor has been evaluated by simulation to confirm the following characteristics. 1. The PLL can detect an initial unlock state and pseudo‐lock state within almost the same time as FDD sampling time and can recover rapidly. 2. The jitter transfer function is almost equal to the usual first‐order PLL and is independent of input data patterns. 3. The FDD frequency detecting range, corresponding to the PLL lock‐in range, is more than four times that of the previously proposed FDD‐PLL. Copyright © 1995 Wiley Periodicals, Inc., A Wiley Company

    DOI： 10.1002/ecjb.4420781213

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  • New very fast pull-in PLL system with anti-pseudo lock function Reviewed

    Shirahama H., Taniguchi K., Nakashi K.

    1993 Symposium on VLSI Circuits Digest of Technical Papers   75 - 76   1993.12

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  • Chip organization of bloch line memory Reviewed

    Suzuki T., Asada H., Matsuyama K., Fujita E., Saegusa Y., Morikawa K., Fujimoto K., Shigenobu M., Nakashi K., Takamatsu B., Konishi S.

    IEEE Transactions on Magnetics   22 ( 5 )   784 - 789   1986.09

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    Language：English   Publishing type：Research paper (scientific journal)

    DOI： 10.1109/TMAG.1986.1064520

    Scopus

    Other Link： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0022778386&origin=inward

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Conference Prsentations (Oral, Poster)

  • A Helmet-type Body Temperature and Heart RateMeasurement System for Heat Stroke Prevention

    2021 IEEE 10th Global Conference on Consumer Electronics 

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    Event date： 2021.10.12 - 2021.10.15   Language：English  

  • On a Tri-State Stochastic Resonance Circuit for Low SNR, Ternary Signal Detection

    Kenichi NAKASHI, Norihiro MISUMI

    The 34th Workshop on Circuits and Systems  The Institute of Electronics, Information and Communication Engineers, Engieering Sciences Society

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    Event date： 2021.08.26 - 2021.08.27   Language：Japanese  

  • On Near-Infrared Optical Properties of Ethanol for a Wearable Blood Alcohol Sensor

    2020 IEEE 9th Global Conference on Consumer Electronics 

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    Event date： 2020.10.13 - 2020.10.16   Language：English  

  • 心拍変動の解析を目的としたR波測定システムの検討

    下田航大,中司賢一

    第73回電気・情報関係学会九州支部連合大会 

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    Event date： 2020.09.26 - 2020.09.27   Language：Japanese  

  • Study on Mistype Correction Support Using Attention in Japanese Input

    Ryuki Komatsu, Rin Hirakawa, Hideaki Kawano, Kenichi Nakashi, Yoshihisa Nakatoh

    2020 IEEE 38th International Conference on Consumer Electronics 

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    Event date： 2020.01.04 - 2020.01.06   Language：English  

  • Electrolarynx System Using Voice Conversion Based on WaveRNN

    Etsuro Urabe, Rin Hirakawa, Hideaki Kawano, Kenichi Nakashi, Yoshihisa Nakatoh

    2020 IEEE 38th International Conference on Consumer Electronics 

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    Event date： 2020.01.04 - 2020.01.06   Language：English  

  • 電車内アナウンス音声と周囲の会話を判別するための音響的特徴量の検討

    木下雄斗,中藤良久,平川凛,中司賢一,河野英昭

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • ディープラーニングを用いたアルコールの分解過程を推測する方法の検討

    狩郷杏人,中司賢一

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • SNS情報を利用した震災時通路被害の推定に関する検討

    三原優二郎,中藤良久,中司賢一,河野英昭,平川凛

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • トラック輸送における車体の振動と荷物の傾きの関連性の検討

    井下千尋,平川凛,中司賢一,河野英昭,中藤良久,中井太地

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • アルコールの近赤外吸収特性の2波長での測定

    永吉賢次,中司賢一

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • インバータによる低消費電力高利得アンプの開発

    塩見涼陽,中司賢一

    第72回電気・情報関係学会九州支部連合大会 

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    Event date： 2019.09.27   Language：Japanese  

  • Programming Assistant System Using Improved Flowchart for The Visually Impaired

    Ryo Hirakawa, Rin Hirakawa, Hideaki Kawano, Kenichi Nakashi, Yoshihisa Nakatoh

    1st International Conference on Human Interaction and Emerging Technologies 

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    Event date： 2019.08.22 - 2019.08.24   Language：English  

  • On a Measurement Method for Alcohol Decomposition Process by Image Recognition using Deep Learnig

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    Event date： 2018.09.27 - 2018.09.28   Language：Japanese  

  • Voltage Boost Circuit Operatable as Low as 80 mV for Low Voltage Energy Harvester

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    Event date： 2017.09.27 - 2017.09.28   Language：Japanese  

  • On a Weak 3-Value Signal Detection by Tri-State Stochastic Resonance

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    Event date： 2017.09.27 - 2017.09.28   Language：Japanese  

  • A Development of Earlobe Attachable In Blood Alcohol Detector

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    Event date： 2017.09.27 - 2017.09.28   Language：Japanese  

  • A 0.2V Analog Comparator with Redundant Inverter Array

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    Event date： 2016.09.29 - 2016.09.30   Language：Japanese  

  • On Detection of Weak Electrocardiograph Signal by Stochastic Resonance

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    Event date： 2016.09.29 - 2016.09.30   Language：Japanese  

  • A Fully-Synthesized Inverter-Array Comparator in 65nm CMOS

    The 29th Workshop on Circuits and Systems 

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    Event date： 2016.05.12 - 2016.05.13   Language：Japanese  

  • A Design of Stochastic Comparators with Redundant Inverter Array

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    Event date： 2015.09.26 - 2015.09.27   Language：Japanese  

  • On Fully-Synthesized Stochastic Comparators with Redundant Inverters

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    Event date： 2015.09.26 - 2015.09.27   Language：Japanese  

  • A Development of Magnetic-Resonant Type Wireless Power Transmission System Using Printed Coils

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    Event date： 2014.09.18 - 2014.09.19   Language：Japanese  

  • A Design of Real-Time FFT for Spectral Analysis of Electrocardiographic Signals

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    Event date： 2014.09.18 - 2014.09.19   Language：Japanese  

  • プリントコイルを用いた磁界共鳴型ワイヤレス給電システムの検討

    中司賢一

    第66回電気関係学会九州支部連合大会 

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    Event date： 2013.09.24 - 2013.09.25   Language：Japanese  

  • 弱反転領域動作オペアンプを用いた低消費電力SCフィルタの設計

    安村雄基

    第66回電気関係学会九州支部連合大会 

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    Event date： 2013.09.24 - 2013.09.25   Language：Japanese  

  • インバータコンパレータによる確率的フラッシュ型ADCの検討

    中司賢一

    第66回電気関係学会九州支部連合大会 

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    Event date： 2013.09.24 - 2013.09.25   Language：Japanese  

  • 0.18μm CMOS サブマイクロワット級リング発振回路の設計

    中司賢一

    第65回電気関係学会九州支部連合大会 

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    Event date： 2012.09.24 - 2012.09.25   Language：Japanese  

  • 試作LSIを用いた生体情報収集システムの開発

    森山崇仁

    第64回電気関係学会九州支部連合大会 

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    Event date： 2011.09.26 - 2011.09.27   Language：Japanese  

  • 化学感覚能センサのための2チャンネルアナログフロントエンドLSIの試作

    本人

    第64回電気関係学会九州支部連合大会 

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    Event date： 2011.09.26 - 2011.09.27   Language：Japanese  

  • 化学感覚能センサのためのスイッチトキャパシタ型フィルタの試作

    本人

    第63回電気関係学会九州支部連合大会 

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    Event date： 2010.09.25 - 2010.09.26   Language：Japanese  

  • プログラマブルな可変フルスケール電流マトリックス型DAC

    本人

    第63回電気関係学会九州支部連合大会 

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    Event date： 2010.09.25 - 2010.09.26   Language：Japanese  

  • 再構成可能なビットスライス型ADコンバータの開発

    本人

    LSIとシステムのワークショップ2010 

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    Event date： 2010.05.17 - 2010.05.19   Language：Japanese  

  • 生体信号用⊿Σ型ＡＤＣのための0.5Ｖ動作ＯＰアンプの設計

    学内博士前期生,外園篤

    平成22年電気学会全国大会 

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    Event date： 2010.03.17   Language：Japanese  

  • 可変VCOのための位相補間回路の検討

    学内博士前期生,大石茂樹

    第22回 電子情報通信学会 シリコンアナログRF研究会 

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    Event date： 2010.03.01   Language：Japanese  

  • 空間分割多重無線のための可変VCOに用いる位相補間回路の振幅特性の向上

    学内博士前期生,上野智史

    第62回電気関係学会九州支部連合大会 

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    Event date： 2009.09.28 - 2009.09.29   Language：Japanese  

  • 生体信号センサの信号処理のためのノッチ/LPFスイッチトキャパシタ型フィルタ

    学内博士前期生,重春和紀

    第62回電気関係学会九州支部連合大会 

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    Event date： 2009.09.28 - 2009.09.29   Language：Japanese  

  • 携帯型センシング機器用超低消費電力ΔΣ変調器の設計

    学内博士前期生,冨田芳洋

    第62回電気関係学会九州支部連合大会 

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    Event date： 2009.09.28 - 2009.09.29   Language：Japanese  

  • 生体信号センサ信号処理のためのスイッチトキャパシタ型フィルタ

    本人

    第62回電気関係学会九州支部連合大会 

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    Event date： 2009.09.28 - 2009.09.29   Language：Japanese  

  • 空間分割多重無線のための可変VCOに用いる位相補間回路の線形性の向上

    学内博士前期生,大石茂樹

    第62回電気関係学会九州支部連合大会 

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    Event date： 2009.09.28 - 2009.09.29   Language：Japanese  

  • pHEMA層の導入による味覚センサチップの作用電極の改良

    九州大学 江藤信一

    応用物理学会九州支部学術講演会 

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    Event date： 2008.11.29 - 2008.11.30   Language：Japanese  

  • 空間分割多重無線に用いる可変VCOの設計

    本人

    第61回電気関係学会九州支部連合大会 

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    Event date： 2008.09.24 - 2008.09.25   Language：Japanese  

  • 味覚センサチップにおける作用電極の改善

    九州大学 江藤信一

    応用物理関係連合講演会 

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    Event date： 2008.03.27 - 2008.03.30   Language：Japanese  

  • センサ信号処理アナログフロントエンド用チョッパスタビライズドアンプの設計

    工学研究科電気工学専攻杉野之信

    第60回電気関係学会九州支部連合大会 

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    Event date： 2007.09.18   Language：Japanese  

  • 0.35μm CMOS ５次バタワーススイッチトキャパシタLPFの設計

    本人

    第60回電気関係学会九州支部連合大会 

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    Event date： 2007.09.18   Language：Japanese  

  • センサシステム用スイッチトキャパシタノッチフィルタの設計

    本人

    第60回電気関係学会九州支部連合大会 

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    Event date： 2007.09.18   Language：Japanese  

  • 味覚センサチップおよびポータブル味覚センサの作製

    九州大学 江藤信一

    応用物理関係連合講演会 

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    Event date： 2007.03.26 - 2007.03.30   Language：Japanese  

  • 福岡知的クラスター研究所(FLEETS)におけるRFチップ試作

    本人

    第10回 電子情報通信学会 シリコンアナログRF研究会 

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    Event date： 2006.11.30   Language：Japanese  

  • 2.4GHz帯で動作するＰＬＬ周波数シンセサイザの設計

    石田誠（九州大学）

    第10回 電子情報通信学会 シリコンアナログRF研究会 

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    Event date： 2006.11.30   Language：Japanese  

  • センサノード用低消費電力スイチットキャパシタLPFの0.35μm CMOS技術による試作

    本人

    第10回システムLSIワークショップ 

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    Event date： 2006.11.28   Language：Japanese  

  • 0.35μm CMOS, 2V動作スイチットキャパシタLPFの設計

    本人

    第59回電気関係学会九州支部連合大会 

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    Event date： 2006.09.29   Language：Japanese  

  • IEEE 802.11b 無線LAN物理層１チップ化の試み

    （財）福岡県産業・科学技術振興財団

    第8回システムLSIワークショップ 

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    Event date： 2004.11   Language：Japanese  

  • 無線LANに使用するPLL周波数シンセサイザの設計

    九州大学

    第2回 シリコンアナログRF研究会 

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    Event date： 2004.08.02   Language：Japanese  

  • CPW整合回路を用いた無線LAN用システムLSIの開発

    九州大学

    第５回LSI・アプリケーション産学連携会議 

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    Event date： 2004.05   Language：Japanese  

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Grants-in-Aid for Scientific Research

  • 感性バイオセンサの開発

    Grant number：18106009  2006.04 - 2011.03   基盤研究(S)

Career of Research abroad

  • Low-power, high-efficiency power supply systems and low-power integrated circuits design

    University of California at Berkeley  Project Year:  2000.04 - 2001.03

Award for Educational Activities

  • 優秀ポスター賞

    2019年度（第72回）電気・情報関係学会九州支部連合大会   2019.09.27