Results 51 to 60 of about 36,170 (260)

Fast Radix-32 Approximate DFTs for 1024-Beam Digital RF Beamforming

IEEE Access, 2020
The discrete Fourier transform (DFT) is widely employed for multi-beam digital beamforming. The DFT can be efficiently implemented through the use of fast Fourier transform (FFT) algorithms, thus reducing chip area, power consumption, processing time ...
Arjuna Madanayake, Renato J. Cintra, Najath Akram, Viduneth Ariyarathna, Soumyajit Mandal, Vitor A. Coutinho, Fabio M. Bayer, Diego Coelho, Theodore S. Rappaport   +8 more
doaj   +1 more source

Chiral Phase Change Nanomaterials

Advanced Functional Materials, EarlyView.
This work demonstrates reversible, non‐volatile phase transitions in chiral Ge2${\rm Ge}_2$Sb2${\rm Sb}_2$Te5${\rm Te}_5$ (GST) nanohelices for high‐speed optical modulation of chirality and dynamic control of the state of polarization (SOP). The chiral nanostructures are fabricated using a highly directional, wafer‐scale physical vapor deposition ...
Joshua A. Burrow, Md Shah Alam, Riad Yahiaoui, Evan M. Smith, Ryan Laing, Jules Gardener, Thomas A. Searles, Piyush J. Shah, Shivashankar Vangala, Joshua R. Hendrickson, Andrew M. Sarangan, Imad Agha   +11 more
wiley   +1 more source

Comparison of Image Compressions: Analog Transformations

Proceedings, 2020
A comparison between the four most used transforms, the discrete Fourier transform (DFT), discrete cosine transform (DCT), the Walsh–Hadamard transform (WHT) and the Haar-wavelet transform (DWT), for the transmission of analog images, varying their ...
Jose Balsa
doaj   +1 more source

From Photoalignment to Structured Light: Liquid Crystal Platforms for Beam Shaping and Complex Wavefronts

Advanced Functional Materials, EarlyView.
Photoaligned and photopatterned liquid crystal platforms provide programmable control of optical phase, polarization, and spin‐orbit interactions, enabling compact generation of structured light and complex wavefronts. This review highlights how tailored molecular orientations transform simple beams into designed optical fields, opening versatile ...
Le Zhou, Tingjun Zhong, Sijie Liu, Pouya Nosratkhah, Ke Xu, Yuzhen Zhao, Kristiaan Neyts   +6 more
wiley   +1 more source

Detection of Hidden Object In Speech Based on Fast Fourier Transform Algorithm [PDF]

Engineering and Technology Journal, 2011
In this paper steganalysis technique is proposed on the basis of spectral domain analysis using Discrete Fourier Transform, Fast Fourier Transform Algorithm (DFT_FFTA).
Mahmud k. Kadum
doaj   +1 more source

Ionic Precursors Transformed Into Vinyl Acetate Synthesis Catalyst via Reaction‐Driven Restructuring

Advanced Functional Materials, EarlyView.
This work demonstrates that a simple physical mixture of Pd and Au ionic precursors, KOAc promoter, and SiO2 support can transform into a highly active vinyl acetate synthesis catalyst through reaction‐driven restructuring. The results highlight reaction‐induced restructuring as an innovative and sustainable catalyst design strategy.
Byeong Jun Cha, Welman C. Elias, Hunter P. Jacobs, Kimberly N. Heck, Saghar Rezaie, Sadegh Yazdi, Kiheon Hong, Justin J. Dodson, Laiyuan Chen, Sean G. Mueller, Steven R. Alexander, Michael S. Wong   +11 more
wiley   +1 more source

Extraordinary n‐type Tellurium‐Free Thermoelectric Performance of Y‐Doped BiSe via Synergistic Effect of Vacancies and Band Engineering

Advanced Functional Materials, EarlyView.
Yttrium doping in Sb‐alloyed BiSe synergistically induces Bi vacancies and flattens conduction bands, simultaneously slashing lattice thermal conductivity by 50% and boosting the power factor. The optimized n‐type Bi0.64Sb0.3Y0.06Se delivers a peak zT of 0.91 at 393 K (average zT 0.76, 300–523 K) and an 8‐pair module with 4.6% conversion efficiency ...
Wenhao Xie, Fang Lyu, Xiaolong Sun, Chang Li, Xiaolu Zhu, Liangwei Hu, Qianfeng Ding, Wenjie Zhou, Muyang Huang, Yineng Gou, Yi Zhao, Han Tang, Wei Cao, Yue Hou, Yun Zheng, Ady Suwardi, Ziyu Wang   +16 more
wiley   +1 more source

Discrete Two-Dimensional Fourier Transform in Polar Coordinates Part I: Theory and Operational Rules

Mathematics, 2019
The theory of the continuous two-dimensional (2D) Fourier transform in polar coordinates has been recently developed but no discrete counterpart exists to date.
Natalie Baddour
doaj   +1 more source

Simultaneous Enhancement of Performance and Stability in Dual‐Gate a‐IGZO Thin‐Film Transistors via Single‐Step Laser Annealing for Capacitor‐Less DRAM

Advanced Functional Materials, EarlyView.
A single‐step laser annealing strategy is presented for dual‐gate a‐IGZO TFTs. The steep thermal gradient induces graded oxygen doping in the channel and simultaneous WOx removal at the contacts, enabling concurrent interface and contact engineering.
Sihyeon Kwon, Junil Kim, Geuntae Park, Minseok Kim, Woohyun Hwang, Wanki Kim, Daewon Ha, Byeongmoon Lee, Jae Eun Jang, Hyuk‐Jun Kwon   +9 more
wiley   +1 more source

An Electrowetting Pump

Advanced Functional Materials, EarlyView.
A tubular electrowetting pump moves alternating droplets through a millimeter‐wide channel in discrete, reversible steps, functioning as a fluidic stepper motor. With no moving parts and electrodes insulated from the liquid, it delivers silent, accurate flow. Flexibility allows the pump to be woven directly into textiles for wearable, medical, and soft‐
Robert Hennig, Herbert Shea
wiley   +1 more source