Results 61 to 70 of about 4,818 (307)

Further evidence of long-term thermospheric density change using a new method of satellite ballistic coefficient estimation

, 2011
Building on work from previous studies a strong case is presented for the existence of a long-term density decline in the thermosphere. Using a specially developed orbital propagator to predict satellite orbit evolution, combined with a new and accurate ...
Lewis, H.G., Arrun Saunders, Swinerd, G.G., Graham Swinerd, Saunders, A., Hugh Lewis   +5 more
core   +1 more source

Satellite Drag Coefficient modeling for Thermosphere Science and Mission Operations

, 2022
Satellite drag modeling remains the largest source of uncertainty affecting space operations in low Earth orbit. The uncertainty stems from inaccurate models for mass density and drag coefficient.
Mehta, Piyush M. (author), Crisp, Nicholas H.; id_orcid, Bruinsma, Sean (author), Crisp, Nicholas H. (author), Sheridan, Philip L., March, Günther, Smriti N. Paul, Siemes, C. (author), Günther March, March, G. (author), Crisp, Nicholas H., Sean Bruinsma, Philip L. Sheridan, Sheridan, Philip L. (author), Mehta, Piyush M., Siemes, Christian, Piyush M. Mehta, Nicholas H. Crisp, Christian Siemes, Paul, Smriti N. (author), Bruinsma, Sean, Paul, Smriti N.   +21 more
core   +1 more source

The Thermosphere Is a Drag: The 2022 Starlink Incident and the Threat of Geomagnetic Storms to Low Earth Orbit Space Operations

Space Weather, 2023
On 03 February 2022, SpaceX launched 49 Starlink satellites, 38 of which re‐entered the atmosphere on or about 07 February 2022 due to unexpectedly high atmospheric drag.
T. E. Berger, M. Dominique, G. Lucas, M. Pilinski, V. Ray, R. Sewell, E. K. Sutton, J. P. Thayer, E. Thiemann   +8 more
doaj   +1 more source

Why Didn't I Get a Payout? Understanding Farmer Choices, Index Insurance, and Basis Risk

Applied Economic Perspectives and Policy, EarlyView.
ABSTRACT Index insurance, while heralded as a potential solution to alleviate poverty and food insecurity among agricultural households, has its own set of challenges, notably basis risk. Basis risk is the discrepancy between the insurance payout and losses incurred, posing a significant deterrent to the adoption of index insurance.
S. Lucille Blakeley, Sean Posey, Kathy Baylis, Daniel Osgood, Stuart Sweeney   +4 more
wiley   +1 more source

Atmospheric Drag Analysis with the AEROS Satellites

Journal of geomagnetism and geoelectricity, 1979
The approach followed in deriving total gas density at perigee from the orbital decay of the AEROS satellites is described. Numerical integration of the drag force acting on the satellite along the orbit is used in an iterative procedure to compute thermospheric density.
ROEMER, M., RICHTER, E., SLOWEY, J. W.
openaire   +2 more sources

Climate Change Mitigation in the Dairy Sector: Uncovering Heterogeneity Through Eco‐Efficiency Clubs

Agribusiness, EarlyView.
ABSTRACT Combining climate change goals with economic targets is crucial for the dairy sector, which is a significant contributor to agricultural greenhouse gas (GHG) emissions worldwide. In this paper, we assess economic and climate change implications of dairy production with panel data of Irish dairy farms from 2013 to 2021.
Doris Läpple, Christian Stetter, Cathal Buckley   +2 more
wiley   +1 more source

Satellite Drag Analysis Using Direct Simulation Monte Carlo (DSMC) [PDF]

, 2018
High altitude research into free molecular flow properties has become more prominent in the aerospace field in recent years due to the rise of private aerospace firms. This led to an increase in satellite launches and greater interest in the behaviour of
Bullard, Jacob
core   +1 more source

EMG‐Driven Telemetry and Inference System for Fish: Pose Reconstruction and Flow Sensing

Advanced Intelligent Systems, EarlyView.
This work introduces an electromyography (EMG)‐driven telemetry framework that reconstructs body pose and infers hydrodynamic conditions in freely swimming fish. A custom 16‐channel archival system records intramuscular EMG, enabling deep‐learning models to decode joint kinematics, classify flow regimes, and reveal channel‐efficient sensing strategies.
Rahdar Hussain Afridi, Waqar Hussain Afridi, Muhammad Hamza, Ahsan Tanveer, Mingxin Wu, Xingwen Zheng, Liang Li, Guangming Xie   +7 more
wiley   +1 more source

Real‐Time Thermospheric Density Estimation via Two‐Line Element Data Assimilation

Space Weather, 2020
Inaccurate estimates of the thermospheric density are a major source of error in low Earth orbit prediction. Therefore, real‐time density estimation is required to improve orbit prediction.
David J. Gondelach, Richard Linares
doaj   +1 more source

Adaptive Macroscopic Ensemble Allocation for Robot Teams Monitoring Spatiotemporal Processes

Advanced Intelligent Systems, EarlyView.
We propose an online, environment feedback‐driven macroscopic ensemble approach to adapt robot team task allocation in spatiotemporal environments by controlling robot populations rather than assigning individual robots, all while maintaining robust team performance even for small teams. Our simulation and experimental results show better or comparable
Victoria Edwards, Thales C. Silva, M. Ani Hsieh   +2 more
wiley   +1 more source