Results 1 to 10 of about 54,491 (120)

Maneuver Strategy for Active Spacecraft to Avoid Space Debris and Return to the Original Orbit

International Journal of Aerospace Engineering, 2022
During normal operation of the on-orbit spacecraft, if some satellite in a nearby orbit suddenly breaks apart, its debris will threat the safe operation of the on-orbit spacecraft.
Qun Fang, Zhen Zhang, Haodong Meng, Xiaolong Wang, Xiuwei Zhang   +4 more
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The long-term transport and radiative impacts of the 2017 British Columbia pyrocumulonimbus smoke aerosols in the stratosphere [PDF]

Atmospheric Chemistry and Physics, 2021
Interactions of meteorology with wildfires in British Columbia, Canada, during August 2017 led to three major pyrocumulonimbus (pyroCb) events that resulted in the injection of large amounts of smoke aerosols and other combustion products at the local ...
S. Das, S. Das, P. R. Colarco, L. D. Oman, G. Taha, G. Taha, O. Torres   +6 more
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Comparative Study of Different Algorithms for a Flight Control System Design and the Potentiality of Their Integration with a Sidestick

Aerospace, 2021
The modern trend of developing highly automated aircraft is characterized by a transition from traditional methods and technical solutions to innovative approaches in order to control the system, inceptor and display design.
Alexandr V. Efremov, Zoe Mbikayi, Eugene V. Efremov   +2 more
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Required Moment Sets: Enhanced Controllability Analysis for Nonlinear Aircraft Models

Applied Sciences, 2021
Attainable moment sets (AMS) are a powerful method to assess aircraft controllability. However, as attainable moment sets only take into account the achievable moment set of the control effectors, they do not assess the required moment set to fulfill the
Max Söpper, Jiannan Zhang, Niclas Bähr, Florian Holzapfel   +3 more
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Trajectory/Path-Following Controller Based on Nonlinear Jerk-Level Error Dynamics

Applied Sciences, 2020
This study proposes a novel, nonlinear trajectory/path-following controller based on jerk-level error dynamics. Therefore, at first the nonlinear acceleration-based kinematic equations of motion of a dynamic system are differentiated with respect to time
Patrick Piprek, Michael M. Marb, Pranav Bhardwaj, Florian Holzapfel   +3 more
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A machine learning methodology for the generation of a parameterization of the hydroxyl radical [PDF]

Geoscientific Model Development, 2022
We present a methodology that uses gradient-boosted regression trees (a machine learning technique) and a full-chemistry simulation (i.e., training dataset) from a chemistry–climate model (CCM) to efficiently generate a parameterization of tropospheric ...
D. C. Anderson, D. C. Anderson, M. B. Follette-Cook, M. B. Follette-Cook, M. B. Follette-Cook, S. A. Strode, S. A. Strode, J. M. Nicely, J. M. Nicely, J. Liu, J. Liu, P. D. Ivatt, P. D. Ivatt, B. N. Duncan   +13 more
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A new airborne laser-induced fluorescence instrument for in situ detection of formaldehyde throughout the troposphere and lower stratosphere [PDF]

Atmospheric Measurement Techniques, 2015
The NASA In Situ Airborne Formaldehyde (ISAF) instrument is a high-performance laser-based detector for gas-phase formaldehyde (HCHO). ISAF uses rotational-state specific laser excitation at 353 nm for laser-induced fluorescence (LIF) detection of HCHO ...
M. Cazorla, G. M. Wolfe, S. A. Bailey, A. K. Swanson, H. L. Arkinson, T. F. Hanisco   +5 more
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Technical note: Constraining the hydroxyl (OH) radical in the tropics with satellite observations of its drivers – first steps toward assessing the feasibility of a global observation strategy [PDF]

Atmospheric Chemistry and Physics, 2023
Despite its importance in controlling the abundance of methane (CH4) and a myriad of other tropospheric species, the hydroxyl radical (OH) is poorly constrained due to its large spatial heterogeneity and the inability to measure tropospheric OH with ...
D. C. Anderson, D. C. Anderson, B. N. Duncan, J. M. Nicely, J. M. Nicely, J. Liu, J. Liu, S. A. Strode, S. A. Strode, M. B. Follette-Cook   +9 more
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Ozone Monitoring Instrument (OMI) Aura nitrogen dioxide standard product version 4.0 with improved surface and cloud treatments [PDF]

Atmospheric Measurement Techniques, 2021
We present a new and improved version (V4.0) of the NASA standard nitrogen dioxide (NO2) product from the Ozone Monitoring Instrument (OMI) on the Aura satellite.
L. N. Lamsal, L. N. Lamsal, N. A. Krotkov, A. Vasilkov, A. Vasilkov, S. Marchenko, S. Marchenko, W. Qin, W. Qin, E.-S. Yang, E.-S. Yang, Z. Fasnacht, Z. Fasnacht, J. Joiner, S. Choi, S. Choi, D. Haffner, D. Haffner, W. H. Swartz, B. Fisher, B. Fisher, E. Bucsela   +21 more
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High-Precision Binary Object Detector Based on a BSF-XNOR Convolutional Layer

IEEE Access, 2021
Recently, building an efficient and robust model for object detection has attracted the attention of the vision community. Although binary networks have a fast inference speed, they cannot be used directly on mobile devices such as unmanned aerial ...
Shaobo Wang, Cheng Zhang, Di Su, Longlong Wang, Huan Jiang   +4 more
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