Details of a Researcher - Yoshioka, Kentaro

Yoshioka, Kentaro

写真a

Affiliation: Faculty of Science and Technology, Department of Electronics and Electrical Engineering （Yagami）

Position: Assistant Professor/Senior Assistant Professor

Related Websites

Computing and Sensing Group (CSG)

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Papers 【 Display / hide 】

Artificial intelligence for diagnosis and Gleason grading of prostate cancer: the PANDA challenge

W Bulten, K Kartasalo, PHC Chen, P Ström, H Pinckaers, K Nagpal, Y Cai, ...

Nature medicine, 1-10 2022
Time-Based Current Source: A Highly Digital Robust Current Generator for Switched Capacitor Circuits

K YOSHIOKA

IEICE Transactions on Electronics, 2021CDP0002 2022
VCO-Based Comparator: A Fully Adaptive Noise Scaling Comparator for High-Precision and Low-Power SAR ADCs

K Yoshioka

IEEE Transactions on Very Large Scale Integration (VLSI) Systems 29 (12 … （IEEE Transactions on Very Large Scale Integration (VLSI) Systems) 29 （ 12 ） 2143 - 2152 2021.12

ISSN 10638210

　View Summary

A voltage-controlled oscillator (VCO)-based comparator that automatically adapts its noise performance reflecting the input voltage difference ( $\Delta V_{\text {in}}$ ) is presented. Such adaptive operation significantly reduces the power of high-precision comparators in successive-approximation-register (SAR) ADCs. $\Delta V_{\text {in}}$ is integrated as a time difference via the VCO, where the integration continues as long as the time difference is below a certain threshold, defined by the phase detector deadzone. Thus, when $\Delta V_{\text {in}}$ is large, the comparator operates as a low-power delay line-based comparator, and with small $\Delta V_{\text {in}}$ , the VCO oscillates to integrate the input signal and suppresses the comparator noise. The required oscillations to complete the comparison are inversely proportional to $\Delta V_{\text {in}}$ , realizing fully adaptive noise and power scaling. This article provides a detailed analysis and specific design guidelines of the VCO comparator. Moreover, the PVT drift tolerance and detailed circuit implementations are deeply discussed as well. For proof-of-concept, a 13-bit SAR ADC with the proposed VCO-based comparator was fabricated in 65-nm CMOS. By off-chip LMS calibration, the ADC achieves peak SNDR 66 dB at 1 MS/s with a peak FoM of 29 fJ/conv.-step.
- Access to Document (DOI)
Through the Looking Glass: Diminishing Occlusions in Robot Vision Systems with Mirror Reflections

K Yoshioka, H Okuni, TT Ta, A Sai

2021 IEEE/RSJ International Conference on Intelligent Robots and Systems … （IEEE International Conference on Intelligent Robots and Systems) 1578 - 1584 2021

ISSN 21530858

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The quality of robot vision greatly affects the performance of automation systems, where occlusions stand as one of the biggest challenges. If the target is occluded from the sensor, detecting and grasping such objects become very challenging. For example, when multiple robot arms cooperate in a single workplace, occlusions will be created under the robot arm itself and hide objects underneath. While occlusions can be greatly reduced by installing multiple sensors, the increase in sensor costs cannot be ignored. Moreover, the sensor placements must be rearranged every time the robot operation routine and layout change.To diminish occlusions, we propose the first robot vision system with tilt-type mirror reflection sensing. By instantly tilting the sensor itself, we obtain two sensing results with different views: conventional direct line-of-sight sensing and non-line-of-sight sensing via mirror reflections. Our proposed system removes occlusions adaptively by detecting the occlusions in the scene and dynamically configuring the sensor tilt angle to sense the detected occluded area. Thus, sensor rearrangements are not required even after changes in robot operation or layout. Since the required hardware is the tilt-unit and a commercially available mirror, the cost increase is marginal. Through experiments, we show that our system can achieve a similar detection accuracy as systems with multiple sensors, regardless of the single-sensor implementation.
- Access to Document (DOI)
System and method

K Yoshioka, H Okuni, A Sai

US Patent App. 17/014,757 2021

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

サイバーとフィジカルを横断したセンサセキュリティ研究

2022.10

-

2026.03

JST, さきがけ, Commissioned ｒesearch, Principal investigator
D3-AI: 多様性と環境変化に寄り添う分散機械学習基盤の創出

2021.10

-

2026.03

JST, CREST, Coinvestigator(s)
LiDAR based Sensing System Focused on Privacy Preserving and Occlusions

2021.08

-

2023.03

MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Research Activity Start-up , Principal investigator

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Awards 【 Display / hide 】

Michael A. Zachariah Outstanding Student Paper Award

K. Yamashita, B. Hershberg, K. Yoshioka, H. Ishikuro, 2023.04, IEEE CICC, A 4.6K to 400K Functional PVT-Robust Ringamp-Based 250MS/s 12b Pipelined ADC with Pole-Aware Bias Calibration

Type of Award： Award from international society, conference, symposium, etc., Country： United States
ETAS Best Short/WIP Paper Award Runner-up

T. Sato, Y.Hayakawa, R.Suzuki, Y.Shiiki, K.Yoshioka, Q. Chen, 2023.02, Vehicle Sec, WIP: Practical Removal Attacks on LiDAR-based Object Detection in Autonomous Driving

Type of Award： Award from international society, conference, symposium, etc., Country： United States