Results 21 to 30 of about 222,732 (294)

Orbit Determination Accuracies Using Satellite-to-Satellite Tracking [PDF]

IEEE Transactions on Aerospace and Electronic Systems, 1978
The results are reported of the ATS-6/GEOS-3 and the ATS-6 NIMBUS-6 satellite-to-satellite orbit determination experiments. NASA intends to use the tracking data relay satellite system for operational orbit determination of NASA satellites. Hence, in the near future, satellite-to-satellite tracking data will be routinely processed to obtain orbits. The
F.O. Vonbun, P.D. Argentiero, P.E. Schmid   +2 more
openaire   +1 more source

A State-Space Approach for Tracking Doppler Shifts in Radio Inter-Satellite Links

IEEE Access, 2021
The high Doppler effects in satellite communications make the equivalent channels fast varying, which leads to channel estimation difficulties and the need for high channel estimation overheads.
Pedro Pedrosa, Daniel Castanheira, Adao Silva, Rui Dinis, Atilio Gameiro   +4 more
doaj   +1 more source

Architecture design of BeiDou global navigation signals

Geo-spatial Information Science
Navigation signals play a crucial role in determining the performance and user experience of Global Navigation Satellite System (GNSS). In recent years, GNSSs have been actively modernizing their signal architectures to meet the increasing demand for ...
Shuren Guo, Chengeng Su, Feiren Lv
doaj   +1 more source

Dynamic thermal and IT resource management strategies for data center energy minimization

Journal of Cloud Computing: Advances, Systems and Applications, 2017
Energy-hungry data centers attract researchers’ attention to energy consumption minimization–a challenge confronted by both industry and academia. To assure the server reliability, its instantaneous temperature is generally controlled within a preset ...
Lijun Fu, Jianxiong Wan, Jie Yang, Dongdong Cao, Gefei Zhang   +4 more
doaj   +1 more source

GPS based vehicle tracking system [PDF]

, 2021
The research is about creating a system for tracking vehicle. Objective of the research is to design and develop a GPS based Vehicle Tracking System in order to display location of vehicle on Google Maps.
Mohd Nazri, Mohd Fiqri, Zohari, Mohd Hakimi   +1 more
core  

Fluid Biomarkers of Disease Burden and Cognitive Dysfunction in Progressive Supranuclear Palsy

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Identifying objective biomarkers for progressive supranuclear palsy (PSP) is crucial to improving diagnosis and establishing clinical trial and treatment endpoints. This study evaluated fluid biomarkers in PSP versus controls and their associations with regional 18F‐PI‐2620 tau‐PET, clinical, and cognitive outcomes.
Roxane Dilcher, Charles B. Malpas, Stuart J. McDonald, William T. O’Brien, Craig Despott, Kelly L. Bertram, Matthew P. Pase, Lukas Frontzkowski, Meng Law, Terence J. O’Brien, Lucy Vivash   +10 more
wiley   +1 more source

Comparing spatial patterns of marine vessels between vessel-tracking data and satellite imagery

Frontiers in Marine Science, 2023
Monitoring marine use is essential to effective management but is extremely challenging, particularly where capacity and resources are limited. To overcome these limitations, satellite imagery has emerged as a promising tool for monitoring marine vessel ...
Shinnosuke Nakayama, WenXin Dong, Richard G. Correro, Elizabeth R. Selig, Colette C.C. Wabnitz, Colette C.C. Wabnitz, Trevor J. Hastie, Trevor J. Hastie, Jim Leape, Serena Yeung, Fiorenza Micheli, Fiorenza Micheli, Fiorenza Micheli   +12 more
doaj   +1 more source

Guidelines for Satellite Tracking [PDF]

, 2010
It is assumed that “space age” started with the first artificial satellite in the orbit around the planet. Nowadays, satellites are used for various different purposes: telecommunications, broadcasting, observation, imaging and even espionage. What they all have in common is the fact that they all must obey the rules of celestial mechanics.
Vuckovic, Dusan, Rajkovic, Petar, Jankovic, Dragan, Pavic, Olivera   +3 more
openaire   +2 more sources

Laser Metal Deposition of Aluminum Alloys 7075 and 5083 with the Addition of Volatile Alloying Elements through Powder Blending

Advanced Engineering Materials, EarlyView.
This study investigates laser metal deposition of aluminum alloys EN AW‐7075 and EN AW‐5083, using powder blending to compensate zinc and magnesium evaporation. In situ alloying and ex situ alloying with ZnAl12 and AZ91 preserve near‐standard compositions and improve mechanical properties.
Finn Bendixen, Anastasiya Toenjes, Annika Bohlen, Thomas Seefeld   +3 more
wiley   +1 more source

Station-Keeping Maneuvers for a Geostationary Satellite Using Linear Quadratic Regulator [PDF]

Journal of Astronomy and Space Sciences, 1997
This paper applied one of the well-known optimal control theory, namely, linear quadratic regulator(LQR), to the station-keeping maneuvers(SKM) for a geostationary satellite.
Sunik Lee, Kyu-Hong Choi, Sanguk Lee
doaj