Results 131 to 140 of about 735,881 (338)
IEEE AccessLow Earth Orbit (LEO) satellites are receiving fresh interest from the wireless communications society. The transceivers on these satellites require high-gain antennas with consistent performance over the operational spectrum.
Mahmoud Gadelrab +3 more
doaj +1 more source
Journal of Quaternary Science, EarlyView.Abstract The sedimentary succession at Whittlesey preserves a unique British late Middle Pleistocene to Holocene record back to a time equivalent to at least marine oxygen isotope stage 8 (ca. 250 ka). This study builds on previously published sedimentology, geochronology and palaeoecology results to establish 20 sedimentary facies associations, with ...
H. E. Langford +3 more
wiley +1 more source
Optimization in the design of a 12 gigahertz low cost ground receiving system for broadcast satellites. Volume 2: Antenna system and interference [PDF]
The antenna characteristics are analyzed of a low cost mass-producible ground station to be used in broadcast satellite systems. It is found that a prime focus antenna is sufficient for a low-cost but not a low noise system.
Albernaz, J. +4 more
core +1 more source
Mass Spectrometry Reviews, EarlyView.ABSTRACT The review examines the evolution of chemical ionization mass spectrometry (CI‐MS), a technique developed in 1966 by Field and Munson. CI is a soft‐ionization method that produces more intense molecular ions with less fragmentation than electron ionization (EI).
Malvika Dutt +4 more
wiley +1 more source
Antenna pattern control using impedence surfaces [PDF]
During this research period, September 16, 1990 to March 15, 1991, a design method for selecting a low-loss impedance material coating for a horn antenna pattern control has been developed.
Balanis, Constantine A., Liu, Kefeng
core +1 more source
Gaussian profiled horn antennas
, 1999 In many different applications parameters such efficiency, gain, directivity, etc., are really critical. By using the Gaussian techniques presented here, the radiating features of existing horn antenna systems can be improved, only by adding some portion of Gaussian horn antenna at the end or designing a new horn antenna system.
Gonzalo García, Ramón +2 more
openaire +2 more sources
Detecting and attributing climate change effects on vegetation: Australia as a test case
PLANTS, PEOPLE, PLANET, EarlyView.Climate change is contributing to vegetation changes that threaten life support systems. Yet, inherent climatic variability and past and present human actions—such as clearing, burning and grazing regimes—also alter vegetation and complicate understanding of vegetation change. Australian ecosystems exemplify such complexity.
Laura J. Williams +14 more
wiley +1 more source
PLANTS, PEOPLE, PLANET, EarlyView.‘Greening’ is often depicted as an inherently benevolent practice, turning arid stretches of land into arable and fertile plots. However, by considering a longer history of place and taking archival records into account, such transformations are rendered more complex and, often, more fraught.
Zsuzsanna Ihar
wiley +1 more source
Single and Dual Helical Polarizers for Millimeter-Wave Horn Antennas
IEEE Open Journal of Antennas and PropagationThis paper presents a helical-based polarizer integrated into the aperture of a pyramidal horn antenna, designed to convert linearly polarized radiated fields into either right- or left-handed circular polarization over two distinct bands. The integrated
Maya Al Ajam +2 more
doaj +1 more source
Path loss characterization of horn-to-horn and textile-to-textile on-body mmWave channels at 60 GHz [PDF]
, 2016 Benjillali, Mustapha +4 more
core +1 more source