Results 81 to 90 of about 15,655 (316)

High‐Index, Low‐Loss Optical Material Platforms for Ultra‐Broadband Ultraviolet‐to‐Visible Achromatic Metalenses

Advanced Functional Materials, EarlyView.
An integrated material platform combining engineered SiNx thin films and printable ZrO2 nanoparticle‐embedded resin enables broadband achromatic metalenses from the ultraviolet to visible range. The demonstrated meta‐optics achieve near‐diffraction‐limited focusing with minimal chromatic aberration.
Hyunjung Kang, Dongmin Jeon, Eunji Lee, Junsuk Rho   +3 more
wiley   +1 more source

The nature of electron density enhancement over a wide altitude range during ionosphere heating experiments at EISCAT

Earth and Planetary Physics
During the course of ionospheric heating experiments, researchers at the European Incoherent Scatter Scientific Association (EISCAT) observed an apparent electron density enhancement.
Jun Wu, Jian Wu, Jie Feng, QingLiang Li, ShuJi Hao, ZhengWen Xu, HaiSheng Zhao, YaBin Zhang   +7 more
doaj   +1 more source

Longitudinal differences in the statistical characteristics of ionospheric spread-F occurrences at midlatitude in Eastern Asia

Earth, Planets and Space, 2019
Spread-F is known as the electron density inhomogeneous structures in F layer of ionosphere and can usually be classified as frequency spread-F (FSF) and range spread-F (RSF).
Ning Wang, Lixin Guo, Zonghua Ding, Zhenwei Zhao, Zhengwen Xu, Tong Xu, Yanli Hu   +6 more
doaj   +1 more source

Antenna and radio channel characterisation for low‐power personal and body area networks

, 2012
PhDThe continuous miniaturisation of sensors, as well as the progression in wearable electronics, embedded software, digital signal processing and biomedical technologies, have led to new usercentric networks, where devices can be carried in the user’s
Khan, Mohammad Monirujjaman
core  

Radio wave propagation in open space areas of a vegetation.

, 2023
Radio wave propagation in open space areas of a vegetation.
Zhangchao Ma (11741986), Chaoyi Zhang (11741983), Xiangna Han (1416850), Jianquan Wang (2275303), Yan Yao (229656), Xiang He (45620)   +5 more
core   +1 more source

3D Printing Innovations in Polymeric Porous and Patterned Architecture

Advanced Functional Materials, EarlyView.
Polymeric foams occupy a unique structural space between dense solids and open networks, where engineered void fraction governs mechanical compliance, thermal resistance, and mass transport. Additive manufacturing now enables precise spatial control over cellular architecture, unlocking designer foam structures across applications spanning crash ...
Dhanush Patil, Sri Vaishnavi Thummalapalli, Clarissa Westover, Arunachalam Ramanathan, M. Taylor Sobzcak, Roumika Patil, Qixuan Xiang, Tiantian Li, Sui Yang, Timothy E. Long, Hongyue Sun, Xianqiao Wang, Yang Liu, Kenan Song   +13 more
wiley   +1 more source

Radio wave propagation modelling using finite element method: Novel approaches to model radio wave propagation and solve complex models efficiently using finite element analysis

, 2010
Fourth generation (4G) wireless communication systems are intended to support high data rates, which require careful and accurate modelling of the radio environment. In this book, finite element based accurate and computationally efficient models of wave
Arshad, Kamran
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Digital radio and its application in the HF (2-30 MHz) band [PDF]

, 2004
The propagation environment at high frequencies (HF, 2-30 MHz) has a significant impact on the performance of radio systems (especially data communications).
Davies, Nigel Clement
core  

Numerical study of mode conversion between lower hybrid and whistler waves on short-scale density striations

, 2008
We present a theoretical and numerical study of linear mode conversion of lower hybrid waves interacting with short-scale density striations in the Earth's ionosphere.
Papadopoulos, K., Papadopoulos, Dennis K., Eliasson, Bengt,, Eliasson, Bengt   +3 more
core   +1 more source

Space weather impact on radio wave propagation [PDF]

, 2023
Propagation parameters of electromagnetic waves such as amplitude, phase and polarization are impacted when traveling within the ionospheric plasma of the Earth. Related effects can be used on one hand to monitor and study the ionosphere by analysing the
Jakowski, Norbert
core