Results 121 to 130 of about 536,235 (301)
Phased array-fed antenna configuration study: Technology assessment [PDF]
Spacecraft array fed reflector antenna systems were assessed for particular application to a multiple fixed spot beam/multiple scanning spot beam system.
Ball, D. E. +2 more
core +1 more source
Focused Ion Beam Milling Strategies of Photonic Crystal Structures in Silicon [PDF]
We report on optimisation of the side wall angle of focused ion beam (FIB) fabricated submicron diameter holes in silicon. Two optimisation steps were performed.
Ay, Feridun +6 more
core +1 more source
Time‐Dependent Oxidation and Scale Evolution of a Wrought Co/Ni‐Based Superalloy
This study shows how a new wrought Co/Ni‐based superalloy resists oxidation at 800 ∘$^\circ$C. The oxide scale changes from rough, fast‐growing spinel to a dense, protective chromia–alumina layer. Atom probe analysis reveals tiny refractory‐rich bubbles at the interface that mark the transition to long‐term, diffusion‐controlled protection ...
Cameron Crabb +6 more
wiley +1 more source
Copper‐based composites enhanced with carbon feature convenient mechanical properties and favorable electric conductivity. Processing via deformation and thermomechanical treatments can introduce advantageous microstructures further enhancing their performance. Herein, copper–graphene powder‐based composites are directly consolidated via rotary swaging
Radim Kocich +3 more
wiley +1 more source
Frequency scanning ring multibeam antenna array
Background. Implementation of scanning antennas for noise-immune communication systems and radar systems is an important and urgent task. One of the most promising methods of beam deflection is frequency scanning, which can be effectively combined with ...
Evgeniy A. Ishchenko +3 more
doaj +1 more source
Laser-scanning techniques for rapid ballistics identification [PDF]
Two different laser-scanning methods may be utilized. In each case scanned cylindrical bullet surface is displayed ""unwrapped'' on oscilloscope screen. Bullets are compared by photographing each display and superimposing negatives of two images.
Nakich, R. B., Woodburgy, R. C.
core +1 more source
Robust Spot Melting by 3D Spot Arrangements in Electron Beam Powder Bed Fusion
This work proposes an approach to replace separately melted contours for spot melting in electron beam powder fusion. Adapting the spot arrangements close to the contour combined with stacking yields a comparable surface quality without the inherent challenges of separate contours, as demonstrated, by electron optical images and roughness measurements.
Tobias Kupfer +4 more
wiley +1 more source
In this paper, a multi-feed transmitarray with high-gain, wide-angle beam-scanning, and low-cost features is presented. A novel hybrid phase distribution (HPD) method is proposed to improve the beam-scanning range by combining the single-focal and ...
Ming Wu, Hang Ren, Jinyang Bi, Fan Qin
doaj +1 more source
Multimodal Data‐Driven Microstructure Characterization
A self‐consistent autonomous workflow for EBSP‐based microstructure segmentation by integrating PCA, GMM clustering, and cNMF with information‐theoretic parameter selection, requiring no user input. An optimal ROI size related to characteristic grain size is identified.
Qi Zhang +4 more
wiley +1 more source
Hydrogen‐Assisted Fracture of Iron‐Based Fe–Ni–Al Alloys
Principal relations and fracture mechanisms of single‐phase and precipitate‐strengthened Fe–Ni–Al alloys subjected to prior electrochemical hydrogen charging are identified. The mechanisms of hydrogen effect on strength and microhardness are discussed, including hydrogen‐induced increase in microhardness and the role of hydrogen in fracture behavior ...
Nataliya Yadzhak +3 more
wiley +1 more source

