MHD Collimation Mechanism in Arched Flux Ropes Characterized Using Volumetric, Time‐Dependent B‐Vector Measurements
Sign Up to like & getrecommendations! Published in 2017 at "Geophysical Research Letters"
DOI: 10.1002/2017gl074505
Abstract: Laboratory measurements of B(x,t) in a volume enclosing portions of two arched flux ropes show flux rope collimation driven by gradients in axial current density. These measurements verify the three predictions of a proposed MHD… read more here.
Keywords: mechanism; flux ropes; mhd collimation; collimation ... See more keywords
Overranging and overbeaming measurement in area detector computed tomography: A method for simultaneous measurement in volume helical acquisition
Sign Up to like & getrecommendations! Published in 2019 at "Journal of Applied Clinical Medical Physics"
DOI: 10.1002/acm2.12650
Abstract: Abstract Purpose We propose a novel method to assess overbeaming and overranging, as well as the effect of reducing longitudinal exposure range, by using a dynamic z‐collimator in area detector computed tomography. Methods and materials… read more here.
Keywords: area detector; dynamic collimator; computed tomography; collimation ... See more keywords
Do radiographers collimate? A retrospective analysis of radiographic collimation of common musculoskeletal examinations at an adult trauma centre
Sign Up to like & getrecommendations! Published in 2022 at "Journal of Medical Radiation Sciences"
DOI: 10.1002/jmrs.630
Abstract: Collimation of the primary beam is an important factor in radiography to reduce dose and improve image quality. The introduction of larger detector plates in direct digital radiography (DR) allows the exposed area to be… read more here.
Keywords: collimation; collimate retrospective; analysis radiographic; radiographic collimation ... See more keywords
The dosimetric enhancement of GRID profiles using an external collimator in pencil beam scanning proton therapy.
Sign Up to like & getrecommendations! Published in 2022 at "Medical physics"
DOI: 10.1002/mp.15523
Abstract: PURPOSE The radiobiological benefits afforded by spatially fractionated (GRID) radiation therapy pairs well with the dosimetric advantages of proton therapy. Inspired by the emergence of energy-layer specific collimators in pencil beam scanning (PBS), this work… read more here.
Keywords: collimation; spot; beam; therapy ... See more keywords
The self-collimation effect induced by non-Hermitian acoustic systems
Sign Up to like & getrecommendations! Published in 2019 at "Applied Physics Letters"
DOI: 10.1063/1.5087162
Abstract: With the proposal of the concept of parity-time-symmetry, more and more exotic properties are being unearthed in non-Hermitian systems. In this work, we investigate the related acoustic feature and phenomenon in two-dimensional phononic crystals with… read more here.
Keywords: direction; collimation; hermitian systems; non hermitian ... See more keywords
Design of highly efficient polarization beam splitter based on self-collimation on Si platform
Sign Up to like & getrecommendations! Published in 2017 at "Journal of Modern Optics"
DOI: 10.1080/09500340.2016.1244294
Abstract: Abstract A highly efficient polarization beam splitter based on self-collimation phenomenon in 2D square array of air holes in Si background is presented. For the presented structural parameters, a broad bandwidth of Δω/ωc = 1.3%… read more here.
Keywords: efficient polarization; beam splitter; polarization beam; collimation ... See more keywords
Impact of Collimation on Radiation Exposure in Adult and Paediatric Digital X-Ray Imaging.
Sign Up to like & getrecommendations! Published in 2021 at "Radiation protection dosimetry"
DOI: 10.1093/rpd/ncab155
Abstract: This study aimed to evaluate the collimation practices and quantify the overexposure due to extensive X-ray field area. The study was carried out in four digital X-ray units (including one paediatric X-ray unit). A total… read more here.
Keywords: adult; field; collimation; digital ray ... See more keywords
Assessment of overranging as a function of pitch, collimation and rotation time for three of the most recent and widespread ct scans in France.
Sign Up to like & getrecommendations! Published in 2022 at "Radiation protection dosimetry"
DOI: 10.1093/rpd/ncac257
Abstract: PURPOSE to assess overranging (OR) as a function of pitch, collimation and rotation time for three commonly used CT models in France. METHODS OR was measured using XR-SP2 Gafchromic films (Ashland, USA) and computed from… read more here.
Keywords: rotation time; pitch; overranging function; collimation ... See more keywords
Study of a multi-pinhole collimation system based small-angle neutron scattering instrument at the Compact Pulsed Hadron Source
Sign Up to like & getrecommendations! Published in 2018 at "Journal of Applied Crystallography"
DOI: 10.1107/s1600576718013730
Abstract: The neutron flux of the Compact Pulsed Hadron Source (CPHS) is about 2–3 orders of magnitude lower than that of large neutron sources, which means that the beam intensity should be improved to achieve good… read more here.
Keywords: neutron; multi pinhole; collimation; pinhole collimation ... See more keywords
Anti-mutation load and error stability of a large aperture lens based on parallel collimation locking.
Sign Up to like & getrecommendations! Published in 2022 at "Applied optics"
DOI: 10.1364/ao.455289
Abstract: Based on the lens of spatial filter parallel auxiliary assembly and collimation method, aiming at the unloading and locking problem of the filter lens after collimating, a lens parallel adjustable axial locking structure was proposed.… read more here.
Keywords: collimation; locking; structure; anti mutation ... See more keywords
Broad-angle coherent perfect absorption-lasing and super-collimation in two-dimensional non-Hermitian photonic crystals.
Sign Up to like & getrecommendations! Published in 2022 at "Optics express"
DOI: 10.1364/oe.481141
Abstract: Coherent perfect absorption-lasing (CPAL) and collimation have been intensively studied for normal and small angle wave incidence. Here, we report a two-dimensional non-Hermitian photonic crystal for broad-angle CPAL and super-collimation. The synergy of a nonsymmorphic… read more here.
Keywords: collimation; two dimensional; absorption lasing; dimensional non ... See more keywords