Results 51 to 60 of about 2,547 (185)

Non‐Uniform Programmable Photonic Waveguide Meshes

open access: yesLaser &Photonics Reviews, EarlyView.
Integrating defect cells into uniform hexagonal waveguide meshes overcomes the fundamental spectral and temporal limitations of programmable photonics. By leveraging the Vernier effect through non‐uniform coupled cavities, this architecture achieves a tenfold increase in free spectral range and ultra‐fast sampling times, paving the way for next ...
Cristina Catalá‐Lahoz, José Capmany
wiley   +1 more source

Optical‐to‐Microcomb Stability Transfer for Ultrastable Timing and Microwave/Millimeter‐Wave Generation

open access: yesLaser &Photonics Reviews, EarlyView.
This work demonstrates a high‐fidelity stability transfer from an optical reference to a high‐repetition‐rate microcomb using a mode‐locked laser bridge. By employing electro‐optic sampling timing detection, femtosecond‐level synchronization and 10−18‐level fractional frequency stability are achieved.
Changmin Ahn   +4 more
wiley   +1 more source

Micro‐Texturized and Ultra‐Soft Dry Electrode for Motion‐Artifact Tolerant and Long‐Term Stable Wearable Electrophysiological Monitoring

open access: yesSmall, EarlyView.
A highly conformal and adhesive dry electrode is developed using a micro‐textured carbon black/PDMS composite. By leveraging spontaneous surface roughness for enhanced mechanical interlocking and integrating a stretchable serpentine interconnector, the device achieves robust skin contact and low impedance.
Sang‐Min Kim   +10 more
wiley   +1 more source

Portable Radar for Noncontact Heart Rate Monitoring and Estrus Detection in Dairy Cows

open access: yesIEEJ Transactions on Electrical and Electronic Engineering, EarlyView.
This study introduces a portable radar system for real‐time monitoring of respiratory and heart rates in dairy cows. It uses millimeter‐wave Frequency Modulated Continuous Wave (FMCW) radar to perform noncontact physiological sensing, reducing behavioral disturbance. The radar system's design prioritizes portability, cost‐effectiveness, and robustness,
Yingxiu Li   +7 more
wiley   +1 more source

Bitstream radar waveforms for generic single-chip radar [PDF]

open access: yesInternational Journal of Microwave and Wireless Technologies, 2017
Bitstreams, square wave digital signals, enable flexible radar implementations in modern digital technology. By using bitstreams in place of analog sinusoidal waveforms, we can realize continuous-wave (CW), stepped-frequency CW, frequency-modulated CW, or even pseudo random noise-sequence and pulsed radars, all with a single bit of amplitude resolution.
Øystein Bjørndal   +2 more
openaire   +1 more source

Calculating the Interconnection Limit from a Comprehensive Voltage Evaluation for Distribution Systems with Large Distributed Energy Resources

open access: yesIEEJ Transactions on Electrical and Electronic Engineering, EarlyView.
Japan is pursuing power source decarbonization and is thus reducing fuel‐based thermal power generation while promoting renewable energy resource use. Given the expected power fluctuations, this transition will require novel voltage management and control methods.
Satoshi Uemura   +2 more
wiley   +1 more source

Performances of Multitones for Ultra-Wideband Software-Defined Radar

open access: yesIEEE Access, 2017
From the literature review, it is apparent that there is a gap in quantifying the performances of multitone waveforms specifically for radar applications and experimental results not commonly found. This paper focuses on the radar performance analysis of
Julien Le Kernec, Olivier Romain
doaj   +1 more source

A perspective on automated rapid eye movement sleep assessment

open access: yesJournal of Sleep Research, Volume 34, Issue 2, April 2025.
Summary Rapid eye movement sleep is associated with distinct changes in various biomedical signals that can be easily captured during sleep, lending themselves to automated sleep staging using machine learning systems. Here, we provide a perspective on the critical characteristics of biomedical signals associated with rapid eye movement sleep and how ...
Mathias Baumert, Huy Phan
wiley   +1 more source

Ambiguity and area preserving linear transformations in over‐the‐horizon radar

open access: yesIET Radar, Sonar & Navigation
The use of recurrent waveforms in over‐the‐horizon radar (OTHR) necessitates techniques for ambiguity resolution and manipulation. This paper provides a number of techniques for manipulating the shape of radar ambiguity functions.
Stephen D. Howard, Van Khanh Nguyen
doaj   +1 more source

Motion Mitigation Techniques for Abdominal and Cardiac MR Imaging

open access: yesJournal of Magnetic Resonance Imaging, Volume 63, Issue 4, Page 917-937, April 2026.
ABSTRACT MRI of the heart and abdominal organs provides unparalleled soft tissue contrast and quantitative biomarkers, yet remains highly susceptible to physiological motion. Contractions of the myocardium, respiratory excursions, peristalsis, vascular pulsatility, and unpredictable bulk patient movement generate artifacts that impair image quality ...
Eric M. Schrauben   +3 more
wiley   +1 more source

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