Results 101 to 110 of about 27,387 (213)
Impact of Mantle Velocity Uncertainty on Receiver‐Function Imaging of the Transition Zone
Geophysical Research Letters, Volume 53, Issue 8, 28 April 2026.Abstract Seismological estimates of the 400‐km and 670‐km mantle discontinuities (d400 and d670) are crucial for understanding the thermochemical structure and dynamics of the mantle transition zone (MTZ). However, artifacts from using ray theory and uncertainties in mantle velocity structure can affect topographic mapping of these boundaries.
Carlos A. M. Chaves +2 more
wiley +1 more source
CT Lilun yu yingyong yanjiuThe Ganquan Loess Plateau Block in the Ordos Basin exhibits promising hydrocarbon exploration potential in its karst reservoirs. However, the seismic imaging quality obtained using conventional methods remains suboptimal due to challenges posed by thick ...
Zhenchuan WANG +7 more
doaj +1 more source
Localizing Access Point Through Simple Gesture
IEEE Access, 2018 It is important to obtain the location of an access point (AP), such as in the scenario of finding rogue AP in public places or designing indoor positioning system based on AP locations.
Yongle Chen +4 more
doaj +1 more source
Parametrization of Fresnel returns in middle-atmosphere radar experiments [PDF]
, 1983 Weak reflections from sharp discontinuities in radio refractivity are usually invoked to explain the results of radio propagation experiments.
Rastogi, P. K.
core +1 more source
Technologies for Near-Field Focused Microwave Antennas
International Journal of Antennas and Propagation, 2017 This paper provides a review spanning different technologies used to implement near-field focused antennas at the microwave frequency band up to a few tens of GHz: arrays of microstrip patches and printed dipoles, arrays of dielectric resonator antennas,
Paolo Nepa +3 more
doaj +1 more source
A MEMS-Controllable Fresnel Zone Plate for Miniaturized UV Spectrometer
Proceedings, 2017 This work presents the design and simulation of a MEMS-controllable linear motion Fresnel Zone Plate (FZP). The focal length of an FZP is a function of incident wavelength.
Elnaz Afsharipour +2 more
doaj +1 more source
Advances in Mechanical Engineering, 2017 This article demonstrates the fabrication of large-scale micro-structures by two-photon polymerization with an integrated long-stroke precision stage. We first design a three-axial stage that combines a piezoelectric transducer stage and a stepper-motor ...
Fu-Cheng Wang +3 more
doaj +1 more source
MRI Compatible Planar Material Acoustic Lenses
Applied Sciences, 2018 Zone plate lenses are used in many areas of physics where planar geometry is advantageous in comparison with conventional curved lenses. There are several types of zone plate lenses, such as the well-known Fresnel zone plates (FZPs) or the more recent ...
Daniel Tarrazó-Serrano +4 more
doaj +1 more source
Fresnel Fibres with Omnidirectional Zone Cross-sections
Optics Express, 2007 Fresnel fibres with silica zones resembling omnidirectional structures with self-imaging properties are proposed. Numerical simulation is carried out on a large air hole Fresnel fibre with a triadic Cantor fractal zone cross-section (FZC). The results show the transmission bandgap of these fibres widens and the practical confinement loss decreases with
Cicero, Martelli, John, Canning
openaire +2 more sources
Radio emission from Air Showers. Comparison of theoretical approaches
, 2013 While the fluorescence and the ground counter techniques for the detection of ultra-high energy cosmic rays (UHECR) were being developed for decades, the interest in the radio detection diminished after the initial experiments in the 1960s.
Belov, Konstantin
core +1 more source