117 research outputs found
Engineering planetary lasers for interstellar communication
Transmitting large amounts of data efficiently among neighboring stars will vitally support any eventual contact with extrasolar intelligence, whether alien or human. Laser carriers are particularly suitable for high-quality, targeted links. Space laser transmitter systems designed by this work, based on both demonstrated and imminent advanced space technology, could achieve reliable data transfer rates as high as 1 kb/s to matched receivers as far away as 25 pc, a distance including over 700 approximately solar-type stars. The centerpiece of this demonstration study is a fleet of automated spacecraft incorporating adaptive neural-net optical processing active structures, nuclear electric power plants, annular momentum control devices, and ion propulsion. Together the craft sustain, condition, modulate, and direct to stellar targets an infrared laser beam extracted from the natural mesospheric, solar-pumped, stimulated CO2 emission recently discovered at Venus. For a culture already supported by mature interplanetary industry, the cost of building planetary or high-power space laser systems for interstellar communication would be marginal, making such projects relevant for the next human century. Links using high-power lasers might support data transfer rates as high as optical frequencies could ever allow. A nanotechnological society such as we might become would inevitably use 10 to the 20th power b/yr transmission to promote its own evolutionary expansion out of the galaxy
PROSPECT: a Matlab tool for spacecraft propulsion comparison
The aim of this thesis is to create a methodology that estimates the characteristics and the mass breakdown of a propulsion system. This includes thrusters, propellant, propellant management, and power system requirements for end-to-end missions.
The first part of the project will concern selecting components from various propulsion systems to build a large database; It will contain data from the previous missions of QinetiQ as well as informations about the state of art technology that is currently available in the market.\\
Different mission requirements will be established with a GUI by the final user. These mission requirements are fundamental for the selection of the propulsion and launcher system. This selection-process doesn't take the other subsystem and the relations into account.
The second part of the project will concern the main MATLAB model, based on the requirements for the mission orbit injection, the station keeping and the desposal.
The results of the MATLAB model will show the best possible pick concerning launcher, propulsion system and a combination of S/C propulsion system and launcher, based on the user defined mission requirements
TinyML: Tools, Applications, Challenges, and Future Research Directions
In recent years, Artificial Intelligence (AI) and Machine learning (ML) have
gained significant interest from both, industry and academia. Notably,
conventional ML techniques require enormous amounts of power to meet the
desired accuracy, which has limited their use mainly to high-capability devices
such as network nodes. However, with many advancements in technologies such as
the Internet of Things (IoT) and edge computing, it is desirable to incorporate
ML techniques into resource-constrained embedded devices for distributed and
ubiquitous intelligence. This has motivated the emergence of the TinyML
paradigm which is an embedded ML technique that enables ML applications on
multiple cheap, resource- and power-constrained devices. However, during this
transition towards appropriate implementation of the TinyML technology,
multiple challenges such as processing capacity optimization, improved
reliability, and maintenance of learning models' accuracy require timely
solutions. In this article, various avenues available for TinyML implementation
are reviewed. Firstly, a background of TinyML is provided, followed by detailed
discussions on various tools supporting TinyML. Then, state-of-art applications
of TinyML using advanced technologies are detailed. Lastly, various research
challenges and future directions are identified.Comment: 12 pags, 3 tables, 4 figure
Aeronautical engineering: A continuing bibliography with indexes (supplement 277)
This bibliography lists 467 reports, articles, and other documents introduced into the NASA scientific and technical information system in Mar. 1992. Subject coverage includes: the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines); and associated aircraft components, equipment, and systems. It also includes research and development in ground support systems, theoretical and applied aspects of aerodynamics, and general fluid dynamics
Aeronautical engineering: A continuing bibliography with indexes (supplement 319)
This report lists 349 reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles
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