Results 91 to 100 of about 83,946 (258)

Strategy optimization method based on UAVs-assisted detection of covert communication

ETRI Journal
Unmanned aerial vehicles (UAVs) are highly mobile and easily deployabledevices that have become an important component of wireless communica-tion countermeasures.
Xiaohan Wang, Wen Tian, Guangjie Liu, Yuwei Dai   +3 more
doaj   +1 more source

Transistor‐Level Activation Functions via Two‐Gate Designs: From Analog Sigmoid and Gaussian Control to Real‐Time Hardware Demonstrations

Advanced Materials, EarlyView.
Screen gate‐based transistors are presented, enabling tunable analog sigmoid and Gaussian activations. The SA‐transistor improves MRI classification accuracy, while the GA‐transistor supports precise Gaussian kernel tuning for forecasting. Both functions are implemented in a single device, offering compact, energy‐efficient analog AI processing ...
Junhyung Cho, Youngmin Han, Won Woo Lee, Youngwoo Yoo, Kannan Udaya Mohanan, Chang‐Hyun Kim, Junhwan Choi, Young‐Joon Kim, Wonjun Shin, Hocheon Yoo   +9 more
wiley   +1 more source

Opportunities of Semiconducting Oxide Nanostructures as Advanced Luminescent Materials in Photonics

Advanced Materials, EarlyView.
The review discusses the challenges of wide and ultrawide bandgap semiconducting oxides as a suitable material platform for photonics. They offer great versatility in terms of tuning microstructure, native defects, doping, anisotropy, and micro‐ and nano‐structuring. The review focuses on their light emission, light‐confinement in optical cavities, and
Ana Cremades, Pedro Hidalgo, David Maestre, Ruth Martínez‐Casado, Emilio Nogales, Beatriz Rodríguez, G. Cristian Vásquez, Bianchi Méndez   +7 more
wiley   +1 more source

Towards a Framework for Covert Communications for Mitigating Traffic Detection Attacks

Computers
This article addresses a critical security challenge in Internet of Things (IoT) systems, which are vulnerable to traffic detection attacks due to their reliance on shared wireless communication channels.
Abdallah Farraj
doaj   +1 more source

Trapped Fluorine Enables Thermally Stable Broadband Photodetection in Graphene/Fluorinated Graphene Heterostructure

Advanced Materials Technologies, EarlyView.
Fluorinated graphene has opened new opportunities for real‐world applications; however, its working and thermal stability are key issues for practical use. This study successfully demonstrates the stability of a fluorinated graphene‐based photodetector, achieved through a graphene, fluorinated graphene heterostructure (Gr/F‐Gr HS).
Mukesh Kumar Thakur, Javier Varillas, Oleksandr Volochanskyi, Golam Haider, Jan Plšek, Farjana J. Sonia, Álvaro Rodríguez, Jaganandha Panda, Martin Mergl, Otakar Frank, Jana Vejpravová, Martin Kalbáč   +11 more
wiley   +1 more source

Food‐Based Edible Wireless Sensing Device with Isotropic Electromagnetic Response for Gastrointestinal Monitoring

Advanced Materials Technologies, EarlyView.
A sensor is fabricated that reflects electromagnetic waves wirelessly using only edible materials. The substrate is made of edible materials such as sugar and starch, and the electrodes are made of gold. This sensor has isotropic electromagnetic wave characteristics in response to rotation.
Ryosuke Matsuda, Kentaro Tomita, Shion Miura, Michiyuki Satoh, Tetsuo Kan, Hiroaki Onoe   +5 more
wiley   +1 more source

The Obama Administration and the Press: Leak Investigations and Surveillance in Post-9/11 America [PDF]

, 2013
U.S. President Barack Obama came into office pledging open government, but he has fallen short of his promise. Journalists and transparency advocates say the White House curbs routine disclosure of information and deploys its own media to evade scrutiny ...
Leonard Downie, Jr.
core  

Millisecond‐Switching Dual‐Band/Dual‐Polarization Ka‐Band Wavefront Control Enabled by a Complementary Liquid‐Crystal Metasurface

Advanced Materials Technologies, EarlyView.
An LCD‐compatible complementary liquid‐crystal metasurface delivers dual‐band, dual‐polarized Ka‐band wavefront control with millisecond switching via a 10‐µm LC gap. Interlaced patch/slot pairs enable independent phase tuning at 28 and 38 GHz, while strategic 45° slot rotation suppresses parasitic resonances. Measurements on a 160 × 160‐cell prototype
Daehyeon Kim, Donggeun An, Hyunjae Shin, Youngno Youn, Wonbin Hong   +4 more
wiley   +1 more source

Design, Analysis, and Performance of a Noise Modulated Covert Communications System

EURASIP Journal on Wireless Communications and Networking, 2008
Ultrawideband (UWB) random noise signals provide secure communications because they cannot, in general, be detected using conventional receivers and are jam-resistant.
Ram M. Narayanan, Matthew W. DeMay, Jack Chuang   +2 more
doaj   +2 more sources

Anti‐Slip Material‐Based Strategies and Approaches

Advanced Materials Technologies, EarlyView.
This review highlights the principle mechanisms of slipping at the microscale, linking contact mechanics with a friction behavior model for surface interfaces. Main strategies to develop anti‐slip properties to the surfaces are discussed alongside standardized testing approaches.
Sogand Abbaspoor‐Zanjani, Carlo Antonini, Teresa Gatti, Mengjiao Wang   +3 more
wiley   +1 more source