Results 41 to 50 of about 1,422 (198)

Zero Watermarking Using Convolutional Additive Self‐Attention Vision Transformer and Discrete Wavelet Transform‐Variance‐Based Feature Descriptor for Medical Image Security in Mobile Healthcare Services

Advanced Intelligent Systems, EarlyView.
A zero‐watermarking algorithm that combines a refined convolutional additive self‐attention vision transformer (CAS‐ViT) with a discrete wavelet transform variance‐based feature descriptor (DVFD) is proposed for protecting the privacy of medical images in mobile healthcare services.
Pei Liu, Yan Yan, Hao Huang, Ping Wang, Weirong Qin, Xiangjian Zuo, Yongqin Li   +6 more
wiley   +1 more source

Hitless Rate Switching for Dynamically Reconfigurable Optical Systems

IEEE Photonics Journal, 2015
We propose a set of techniques to enable hitless rate switching for reconfigurable optical systems and validate, by computer simulations, their applicability to NRZ, RZ, and Nyquist pulse shapes. The polarization-multiplexed quadrature phase-shift keying
Valery N. Rozental, Darli A. A. Mello
doaj   +1 more source

Ultrasonic Rainbow: A Meta‐Transducer for Frequency‐Selective Elastic Wave Control via Dithering‐Based Wavenumber Tuning

Advanced Intelligent Systems, EarlyView.
A piezoelectric meta‐transducer generates an ultrasonic rainbow, steering guided elastic waves to different angles according to frequency. A dithering‐based binary electrode design enables a closer realization of the target wavenumber filter, improving directional purity and suppressing unwanted lobes. Numerical and experimental validation demonstrates
Masoud Mohammadgholiha, Jochen Moll, Kilian Tschöke, Carsten Kruska, Sylvia E. Gebhardt, Luca De Marchi   +5 more
wiley   +1 more source

Retinal Vessel Segmentation: A Comprehensive Review From Classical Methods to Deep Learning Advances (1982–2025)

Advanced Intelligent Systems, EarlyView.
Four decades of retinal vessel segmentation research (1982–2025) are synthesized, spanning classical image processing, machine learning, and deep learning paradigms. A meta‐analysis of 428 studies establishes a unified taxonomy and highlights performance trends, generalization capabilities, and clinical relevance.
Avinash Bansal, Jan Kubíček, Jana Bahrová, Alice Varyšová, Martin Augustýnek, Marek Penhaker, Juraj Timkovič   +6 more
wiley   +1 more source

Quadrature phase shift keying coherent state discrimination via a hybrid receiver

New Journal of Physics, 2012
We propose and experimentally demonstrate a near-optimal discrimination scheme for the quadrature phase shift keying (QPSK) protocol. We show in theory that the performance of our hybrid scheme is superior to the standard scheme—heterodyne detection—for ...
C R Müller, M A Usuga, C Wittmann, M Takeoka, Ch Marquardt, U L Andersen, G Leuchs   +6 more
doaj   +1 more source

An Unbalanced QPSK-Based Integrated Communication-Ranging System for Distributed Spacecraft Networking

Sensors, 2020
The spacecraft tracking telemetering and command (TT&C) system plays an essential role in celestial and terrestrial networks, requiring relative ranging and communication, particularly in satellite formation flying networks and distributed spacecraft ...
Na Zhao, Qing Chang, Hao Wang, Zhibo Zhang   +3 more
doaj   +1 more source

3D convolutional neural networks based automatic modulation classification in the presence of channel noise

IET Communications, 2022
Automatic modulation classification is a task that is essentially required in many intelligent communication systems such as fibre‐optic, next‐generation 5G or 6G systems, cognitive radio as well as multimedia internet‐of‐things networks etc.
Rahim Khan, Qiang Yang, Inam Ullah, Ateeq Ur Rehman, Ahsan Bin Tufail, Alam Noor, Abdul Rehman, Korhan Cengiz   +7 more
doaj   +1 more source

Material‐Driven Neuronal Oscillators and Filters via Active Reactance in CC‐NDR and VC‐NDR Electro‐Thermal Memristors

Advanced Physics Research, EarlyView.
Active reactance in electro‐thermal memristors emerges intrinsically from rapid thermal switching of device resistance, linking current‐controlled and voltage‐controlled negative differential resistance to neuronal spiking dynamics. Opposing temperature coefficients of resistance give rise to active inductive or capacitive responses, enabling tunable ...
Fatme Jardali, Gwyneth Svatek, R. Stanley Williams, Timothy D. Brown, Patrick J. Shamberger   +4 more
wiley   +1 more source

Design and Performance Analysis of Differential Chaos Shift Keying System With Dual-Index Modulation

IEEE Access, 2019
In order to sufficiently utilize the time slot resources of the recently proposed pulse-position-modulation differential chaos shift keying (PPM-DCSK), we apply dual-index modulation to differential chaos shift keying and then present two differential ...
Xiangming Cai, Weikai Xu, Lin Wang, Fang Xu   +3 more
doaj   +1 more source

Efficiency of adaptive filter with envelope tracking algorithm when receiving signals with multi-position PSK against the background of non-fluctuation interferences

Российский технологический журнал, 2020
The energy and spectral advantages of signals with phase-shift keying predetermined their widespread use in modern digital navigation, communications and television systems.
G. V. Kulikov, Trung Tien Do
doaj   +1 more source