Results 91 to 100 of about 181,132 (305)

Compact Planar Sparse Array Antenna with Optimum Element Dimensions for SATCOM Ground Terminals

International Journal of Antennas and Propagation, 2015
A novel antenna array architecture for low-cost and compact SATCOM mobile terminal is presented. Based on equal-amplitude aperiodic phased array with fewer active chain numbers, it possesses advantages including lower weight, less cost, and higher power ...
Junqi Lu, Yongxin Guo
doaj   +1 more source

Coaxial phased array antenna [PDF]

, 1980
A coaxial antenna array for communicating circularly polarized electromagnetic radiation is disclosed. A pair of open ended antenna cavities is coaxially constructed and operates by excitation of linear radiation elements arranged within each of the ...
Ellis, H., Jr.
core   +1 more source

Radiation Pattern Synthesis Using Hybrid Fourier- Woodward-Lawson-Neural Networks for Reliable MIMO Antenna Systems

, 2017
In this paper, we implement hybrid Woodward-Lawson-Neural Networks and weighted Fourier method to synthesize antenna arrays. The neural networks (NN) is applied here to simplify the modeling of MIMO antenna arrays by assessing phases. The main problem is
Bouallegue, Ammar, Chouinard, Jean-Yves, Fattahi, Jaouhar, Ghayoula, Elies, Ghayoula, Ridha, Pricop, Emil   +5 more
core   +1 more source

Application of Raman and Photoluminescence Spectroscopy to MgO‐C Refractories

Advanced Engineering Materials, EarlyView.
Visible to near infrared luminescence of MgO is studied on MgO‐C bricks and nominally pure MgO powder, with focus on two similar sharp high‐intensity signals, at 699 and 871 nm, each surrounded by symmetrical sidebands. The nature of these sidebands is investigated by temperature‐dependent spectroscopic measurements, confirming phonon involvement by ...
Julia Richter, Felix Drechsler, Till M. J. Stadtmüller, Cameliu Himcinschi, Christos G. Aneziris, Jens Kortus   +5 more
wiley   +1 more source

Comparing Mutual Coupling of Ring Metamaterial on Square and Vivaldi Array Antennas

Buletin Pos dan Telekomunikasi: Media Komunikasi Ilmiah, 2020
The antenna performance is seen from the S-parameter value. The S-parameter graph can be seen as the return loss (S11, S22) and the mutual coupling (S21, S12) value.
Petrus Kerowe Goran, Eko Setijadi
doaj   +1 more source

Air‐Pressure–Actuated Vibroacoustic Metamaterial With Tunable Bandgap: Design, Modeling, and Characterization

Advanced Engineering Materials, EarlyView.
This article presents the design, modeling, and characterization of air‐pressure–actuated programmable vibroacoustic metamaterials (PVAMM). The study focuses on leveraging air pressure to dynamically tune resonance frequencies for effective noise attenuation.
William Kaal, Michael M. Becker, Sarah C. L. Fischer   +2 more
wiley   +1 more source

Al–Cu Composite Casting of Laser‐Deoxidized Copper: Bonding, Interfacial Chemistry, and Thermal Conductivity

Advanced Engineering Materials, EarlyView.
This study investigates laser‐based oxide removal of Cu inserts in oxygen‐free conditions and examines long‐term oxidation kinetics and surface chemistry under different atmospheres via X‐ray photoelectron spectroscopy. Al–Cu compound casting with differently oxidized surfaces is performed, and intermetallic phase formation, morphology, and thermal ...
Timon Steinhoff, Finn‐Lennard Janthur, Sascha Zimmermann, Sarah Seffer, Jörg Hermsdorf, René Gustus, Ludger Overmeyer, Wolfgang Maus‐Friedrichs, Hans Jürgen Maier, Christian Klose   +9 more
wiley   +1 more source

Dielectric Barrier Discharge Plasma Deoxidation of Natively Oxide Layer of Copper Powders in a Fluidized Bed

Advanced Engineering Materials, EarlyView.
This paper presents a novel approach to reducing oxide layers on metal powders using low‐temperature hydrogen dielectric barrier discharge plasmas at atmospheric pressure. Unlike conventional hydrogen‐plasma reductions, the powders do not contact the plasma directly.
Shukang Zhang, Annett Wollmann, Thomas Gimpel, Alfred P. Weber   +3 more
wiley   +1 more source

Surface Tension Measurement of Ti‐6Al‐4V by Falling Droplet Method in Oxygen‐Free Atmosphere

Advanced Engineering Materials, EarlyView.
In this article, the temperature‐dependent surface tension of free falling, oscillating Ti‐6Al‐4V droplets is investigated in both argon and monosilane doped, oxygen‐free atmosphere. Droplet temperature and oscillation are captured with one single high‐speed camera, and the surface tension is calculated with Rayleigh's formula.
Johannes May, Finn‐Lennard Janthur, Lena Kreie, Michael Müller, Sarah Seffer, Nick Schwarz, Jörg Hermsdorf, Thomas Hassel, Stefan Kaierle, Ludger Overmeyer   +9 more
wiley   +1 more source

Numerical Modeling of Tank Cars Carrying Hazardous Materials With and Without Composite Metal Foam

Advanced Engineering Materials, EarlyView.
Large‐scale puncture models consisting of hazardous materials (HAZMATs) tank car with protective steel–steel composite metal foam (S–S CMF) are solved numerically. Tank car plate with added 10.91–13.33 mm thick S–S CMF layer does not puncture. Protective S–S CMF absorbs impact energy, reduces plate deformation, and prevents shear bands formation ...
Aman Kaushik, Afsaneh Rabiei
wiley   +1 more source