Results 51 to 60 of about 93,870 (317)
Removing Orbital Debris with Lasers
, 2011 Orbital debris in low Earth orbit (LEO) are now sufficiently dense that the use of LEO space is threatened by runaway collisional cascading. A problem predicted more than thirty years ago, the threat from debris larger than about 1 cm demands serious ...
Alexander Rubenchik +41 more
core +1 more source
A Method for Establishing a Station-Keeping, Stratospheric Platform for Astronomical Research
, 2015 During certain times of the year at middle and low latitudes, winds in the upper stratosphere move in nearly the opposite direction than the wind in the lower stratosphere. Here we present a method for maintaining a high-altitude balloon platform in near
Brown, Yorke, Fesen, Robert
core +1 more source
Three years of experience with the STELLA robotic observatory [PDF]
, 2010 Since May 2006, the two STELLA robotic telescopes at the Izana observatory in Tenerife, Spain, delivered an almost uninterrupted stream of scientific data.
Granzer, Thomas +2 more
core +4 more sources
Pilots' use of a traffic alert and collision-avoidance system (TCAS 2) in simulated air carrier operations. Volume 2: Appendices [PDF]
, 1989 Pilots' use of and responses to a traffic alert and collision-avoidance system (TCAS 2) in simulated air carrier line operations are discribed in Volume 1.
Billings, Charles E. +5 more
core +1 more source
Advanced Materials, EarlyView.This review highlights the role of self‐assembled monolayers (SAMs) in perovskite solar cells, covering molecular engineering, multifunctional interface regulation, machine learning (ML) accelerated discovery, advanced device architectures, and pathways toward scalable fabrication and commercialization for high‐efficiency and stable single‐junction and
Asmat Ullah, Ying Luo, Stefaan De Wolf
wiley +1 more source
Beyond Earth: Resilience of Quasi‐2D Perovskite Solar Cells in Space
Advanced Materials, EarlyView.In the article (DOI: 10.1002/adma.202520433), Christoph Putz and co‐workers demonstrate rigid quasi‐2D perovskite solar cells operating in low Earth orbit, delivering stable power for more than 100 days under real‐space conditions. In‐orbit performance is correlated with extensive ground‐based thermal and proton‐irradiation studies on rigid and ...
Christoph Putz +17 more
wiley +1 more source
Low angle estimation in MIMO radar based on unitary ESPRIT under spatial smoothing
IET Radar, Sonar & NavigationAiming at the problem that the overlapping of multipath signals seriously affects the radar's performance of the elevation angle estimation for low‐altitude targets, the authors combine the unitary ESPRIT (UESPRIT) and the multi‐input and multi‐output ...
Cong Qin +4 more
doaj +1 more source
Concepts of spawning targets [PDF]
, 2000 This report discusses the concepts of spawning targets. Spawning target setting is based on the fact that the number of smolts produced by any given river is constrained by habitat availability.
core
Advanced Materials, EarlyView.Stacked nanoflake assembly (SNA) membranes can oscillate autonomously, offering opportunities for soft actuation and energy harvesting. This work uncovers the physical mechanism behind the sustained oscillation of SNA membranes in gradient humidity and identifies three governing dimensionless parameters, enabling rational design for optimizing SNA ...
Zijing Zhang +5 more
wiley +1 more source
Situation Awareness and Tracking Algorithm for Countering Low-Altitude Swarm Target Threats
Remote SensingThe escalating threat posed by low-altitude swarm targets underscores the critical need for precise tracking and situation awareness to secure key areas.
Nannan Zhu +5 more
doaj +1 more source