Results 41 to 50 of about 993 (170)

Fast Localized Calibration for Spatial‐Spectral Excitation Without Fly‐Back Gradients

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Standard spatial‐spectral excitation pulses apply a fly‐back gradient between sub‐pulses, limiting, for example, how thin the slices can be (> 4 mm). Without fly‐back gradients, slices can be as thin as 1.7 mm but require a phase calibration for the sub‐pulses with inverted gradients due to system imperfections.
Michael Schär, Sandeep K. Ganji, Robert G. Weiss, Allison G. Hays   +3 more
wiley   +1 more source

Analogue optical pattern recognition for cross‐correlational CNN

Journal of Microscopy, EarlyView.
Abstract Pattern recognition in convolutional neural networks (CNNs) is computationally intensive due to its reliance on 2D convolutions, requiring significant processing power and time. This paper proposes an analogue optical hardware system to improve CNN efficiency, focusing on forward propagation tasks such as data preparation, correlation, and ...
Ahmed Farhat, Wim J. C. Melis
wiley   +1 more source

Orthogonal Polyphase Coded Waveform Design Method for Simultaneous Fully Polarimetric Radar

Leida xuebao, 2017
To obtain an accurate polarization scattering matrix, simultaneous full polarization radar systems must transmit two signals. The performance of orthogonal polyphase codes designed by the traditional method is limited by the code length and is sensitive ...
Wang Fulai, Pang Chen, Li Yongzhen, Wang Xuesong   +3 more
doaj   +1 more source

Arc‐ZTE: Continuously‐Slewed Zero‐TE Imaging With Incoherent Temporal Sampling for Near‐Silent Dynamic MRI

Magnetic Resonance in Medicine, Volume 96, Issue 4, Page 1726-1740, October 2026.
ABSTRACT Purpose To enable flexible dynamic and DCE MRI with low acoustic noise and high spatiotemporal resolution using zero echo time (ZTE) imaging. Methods This work proposes Arc‐ZTE, a technique in which the readout gradients of ZTE are continuously‐slewed to form arcs in k‐space that are sequentially rotated to yield an incoherent trajectory ...
Shreya Ramachandran, Tobias C. Wood, Gavin Zhang, Ali B. Syed, Shreyas S. Vasanawala, Michael Lustig   +5 more
wiley   +1 more source

Ultra Compact and Broadband Fiber Facet Graphene Oxide Microlens Array Fabricated on a Beam‐Expanding Fiber Facet Using Femtosecond Laser Direct Writing Technique

Nanophotonics, Volume 15, Issue 15, 13 August 2026.
A 400 nm graphene oxide film on a beam‐expanding fiber facet is patterned by femtosecond laser direct writing into a 19‐lens microlens array. The device simultaneously splits a single input beam into multiple 0.67–0.74 NA focus spots with a broadband response from 850 to 1550 nm.
Xiaoke Chen, Lin Ma, Linbin Bai, Tianqi Cheng, Zuyuan He   +4 more
wiley   +1 more source

Sidelobe reduction for plane wave compounding with a limited frame number

BioMedical Engineering OnLine, 2018
Background In ultrasound plane wave imaging (PWI), image details are often blurred by the off-axis artefacts resulting from high sidelobe. Recently plane wave compounding (PWC) is proposed as a promising technique for the sidelobe suppression in the PWI.
Wei Guo, Yuanyuan Wang, Guoqing Wu, Jinhua Yu   +3 more
doaj   +1 more source

BA-Based Low-PSLL Beampattern Synthesis in the Presence of Array Errors

IEEE Access, 2022
In practical scenarios, there are always array errors, which would increase the sidelobe level (SLL) of the array and distort the performance of the electronic devices consequently.
Anyi Wang, Xuhong Li, Yanhong Xu
doaj   +1 more source

Enhanced Retrieval of Spring Snow Depth Over Pan‐Arctic Sea Ice From AMSR2 Observations for 2013–2023 Using Multi‐Model Machine Learning

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 4, August 2026.
Abstract Snow on sea ice modulates the Earth's radiation budget and sea ice mass balance, yet satellite retrievals of Arctic snow depth remain subject to substantial algorithmic uncertainty. We develop a multi‐model machine learning (ML) framework for retrieving spring snow depth over Arctic sea ice from Advanced Microwave Scanning Radiometer 2 (AMSR2).
Yi Zhou, Chentong Zhang, Alek Petty, Xianwei Wang, Ruibo Lei, Wenxuan Liu, Yu Zhang   +6 more
wiley   +1 more source

Binary Sequences with Minimum Peak Sidelobe Level up to Length 68

CoRR, 2012
Results of an exhaustive search for minimum peak sidelobe level binary sequences are presented. Several techniques for efficiency implementation of search algorithm are described. A table of number of non-equivalent optimal binary sequences with minimum peak sidelobe (MPS) level up to length 68 is given.
Anatolii Leukhin, Egor Potehin
openaire   +2 more sources

Optical Phased Arrays on Photonic Integrated Circuit Platforms: Challenges, Opportunities, and Future Applications

Nanophotonics, Volume 15, Issue 14, 27 July 2026.
Integrated optical phased arrays are emerging as scalable engines for solid‐state beam steering and programmable wavefront control. This Review maps the field from beam‐steering principles and core building blocks to material platforms, system‐level bottlenecks, and application frontiers, highlighting how heterogeneous integration, aperiodic ...
Jingwei Li, Yuyuan Han, Aoxiang Chen, Pengpeng Li, Xinglin Zhu, Guanbao Zhao, Luohan Peng, Huaibin Zheng   +7 more
wiley   +1 more source