Results 101 to 110 of about 41,145 (313)

A STUDY ON THE KOREAN IONOSPHERIC VARIABILITY [PDF]

Journal of Astronomy and Space Sciences, 1992
The ionosphere in accordance with solar activity can affect the transmission of radio waves. The effect of the ionosphere on the radio wave propagation are scattering of radio waves, attenuation, angle error, ranging error, and time delay.
Seok-Hee Bae, Kyu-Hong Choi, Jai-Rim Yuk, Hong-Ik Kim, Kyoung W. Min   +4 more
doaj  

Measurement-Based Feasibility Exploration on Detecting and Localizing Multiple Humans Using MIMO Radio Channel Properties

IEEE Access, 2020
This paper explores the feasibility of using the multiple-input multiple-output (MIMO) radio channel properties to passively detect and localize multiple humans in indoor environments.
Yang Miao, Emmeric Tanghe, Jun-Ichi Takada, Troels Pedersen, Pierre Laly, Davy P. Gaillot, Martine Lienard, Luc Martens, Wout Joseph   +8 more
doaj   +1 more source

Spatially Modulated Morphotropic Phase Boundaries in a Compressively Strained Multiferroic Thin Film

Advanced Functional Materials, EarlyView.
ABSTRACT The coexisting rhombohedral‐like (R′, MA) and tetragonal‐like (T′, MC) monoclinic phases in compressively strained bismuth ferrite thin films exhibit exceptional piezoelectric and magnetic properties. While previous studies have largely focused on probing the morphotropic phase boundaries (MPBs) comprising ordered R′/T′ twins, their self ...
Ting‐Ran Liu, Xiangwei Guo, Sajid Husain, Maya Ramesh, Pushpendra Gupta, Darrell Schlom, Ramamoorthy Ramesh, Yu‐Tsun Shao   +7 more
wiley   +1 more source

Temporal evolution of pump beam self-focusing at the High-Frequency Active Auroral Research Program [PDF]

, 2007
On 4 February 2005 the High-Frequency Active Auroral Research Program (HAARP) facility was operated at 2.85 MHz to produce artificial optical emissions in the ionosphere while passing through the second electron gyroharmonic.
Gerken-Kendall, E., Pedersen, T., Kosch, Mike J., Mishin, E., Watkins, B., Starks, M., Oyama, S., Sentman, D.   +7 more
core  

Achieving High ON State Current through Ferroelectric Polarization‐Dependent Interfacial Resistance Switching in Undoped Orthorhombic HfO2 Films

Advanced Functional Materials, EarlyView.
Ferroelectric tunnel junction devices based on epitaxial undoped ferroelectric HfO2 films demonstrate stable switching endurance of over 106 switching cycles, low write voltages of ±3 V, 16 measured resistance states, and neuromorphic capability.
Markus Hellenbrand, Nuno Estrócio, Ji S. Kim, Babak Bakhit, Marian C. Istrate, Corneliu Ghica, Tiago Rebelo, Nives Strkalj, Abin Varghese, Bernardo Almeida, Luís S. Marques, Bipin Rajendran, Judith L. MacManus‐Driscoll, José P. B. Silva   +13 more
wiley   +1 more source

Unlocking Multi‐Valley Energy Pockets and Interface‐Induced Phonon Filtering in InSb Thermoelectrics by Reaction‐Driven Interface Engineering

Advanced Functional Materials, EarlyView.
InSb, a narrow‐bandgap semiconductor with high carrier mobility, is promising for thermoelectric energy conversion but suffers from high lattice thermal conductivity and strong bipolar conduction. Here, in situ interface engineering using Co2O3 nanoprecursors forms hierarchical CoSbx/In2O3/CoSb3 heterostructures that enhance phonon scattering and ...
Jiwu Xin, Xiao Yang, Xiao‐Lei Shi, Chengyun Xu, Xi Ling, Pengyu Zhang, Jinfeng Dong, Yong Du, Haisheng Chen, Ting Zhang, Zhi‐Gang Chen   +10 more
wiley   +1 more source

A Search for Gravitational Waves from Perturbed Black Hole Ringdowns in LIGO Data [PDF]

, 2008
According to General Relativity a perturbed black hole will return to a stable configuration by the emission of gravitational radiation in a superposition of quasi-normal modes. Such a perturbation will occur due to the coalescence of a black hole binary,
Goggin, Lisa Maria
core   +1 more source

Design Strategies and Emerging Applications of High‐Performance Flexible Piezoresistive Pressure Sensors

Advanced Functional Materials, EarlyView.
Flexible piezoresistive pressure sensors underpin wearable and soft electronics. This review links sensing physics, including contact resistance modulation, quantum tunneling and percolation, to unified materials/structure design. We highlight composite and graded architectures, interfacial/porous engineering, and microstructured 3D conductive networks
Feng Luo, Artur Ciesielski, Paolo Samorì   +2 more
wiley   +1 more source

The radio environment for a space-based low-frequency radio astronomy instrument [PDF]

, 2019
Opening the last frequency window for radio astronomy in the sub - 30 MHz region includes a few challenges. First of all, at frequencies below 30 MHz the Earths ionosphere severely distorts radio waves originating from celestial sources, and it ...
Albert Jan Boonstra, Vugt, Pieter van, Wouter Horlings, van Vugt, Pieter, Horlings, Wouter, Pieter van Vugt, Bentum, Mark J., Bentum, MJ, Boonstra, Albert Jan, Mark J. Bentum   +9 more
core   +1 more source

Impact of Plasma Bubbles on OTHR Shortwave Propagation in Different Backgrounds

Remote Sensing
Plasma bubbles represent notable ionospheric irregularities primarily observed in low latitudes, characterized by plasma depletions exhibiting large spatial scales, which can make a significant impact on the propagation of OTHR (over-the-horizon radar ...
Xin Ma, Peng Guo, Ding Yang, Mengjie Wu, Hengyi Yue   +4 more
doaj   +1 more source