Results 241 to 250 of about 1,734,402 (280)

Orbit Predictions for CHAMP — Development and Status

2003
Accurate CHAMP orbit predictions labelled as the PreDicted Science Orbit (PDO) are generated on a sub-daily basis by an automated processor in particular to support the operations of the ground station network of the International Laser Ranging Service (ILRS).
Schmidt, R., Baustert, G., König, R., Reigber, C.   +3 more
openaire   +2 more sources

An XGBoost-Based Method for Improved Orbit Prediction With an Orbit-Separate Modeling Strategy

IEEE Transactions on Aerospace and Electronic Systems
Guangzhi Qu, Wenbin Huang
exaly   +2 more sources

Orbit Predictions for CHAMP and GRACE

2010
The orbit prediction system of GFZ is an indispensable tool for Satellite Laser Ranging (SLR) stations tracking the satellites CHAMP, GRACE-A/B, and TerraSAR-X, for providing orbit information for initial processing of mission data, and for the purpose of mission operations.
Snopek, K., König, D., König, R.
openaire   +3 more sources

Orbit prediction and shuttle rendezvous strategy for eureca

Acta Astronautica, 1983
The European Retrievable Carrier (EURECA) is a platform to be launched and retrieved by the Space Shuttle. An analytical approach is presented for EURECA to execute the first part of the rendezvous manuevers. As part of the solution a new drag perturbation theory is developed, which includes analytical air density models and aerodynamic cross sections.
Klinkrad, H., Janin, G.
openaire   +2 more sources

The prediction of satellite orbits

1963
In this paper we develop a perturbation method and apply it to the prediction of orbits of earth satellites that are disturbed by various external forces. The theory of resonances and stable orbit configurations, possible when sunlight pressure is important, are also analyzed.
openaire   +1 more source

GNSS orbit prediction with enhanced force model

2015 International Conference on Location and GNSS (ICL-GNSS), 2015
Orbit prediction algorithms can be used in a portable positioning device to reduce the Time to First Fix and to augment the received broadcast ephemeris. In this work, we study the two-week prediction accuracy improvement that can be obtained when adding some smaller forces to our previously developed algorithm.
Andrei Pukkila, Juha Ala-Luhtala, Robert Piché, Simo Ali-Löytty   +3 more
openaire   +2 more sources

Preoperative imaging to predict orbital invasion by tumor

Head & Neck, 2000
Our purpose was to examine the accuracy of preoperative imaging in assessing tumor invasion of the orbit and nasolacrimal system.Nineteen preoperative CT and 17 preoperative MR images from patients at risk for orbital invasion were retrospectively reviewed.
M D, Eisen, D M, Yousem, L A, Loevner, E R, Thaler, W B, Bilker, A N, Goldberg   +5 more
openaire   +2 more sources

A multirate predictive approach to orbit control of small spacecraft

Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301), 2002
The problem of orbit control for a small spacecraft is analysed and a solution based on predictive control is proposed. In particular, it is shown how a typical system requirement related to the actual implementation of the control action can be readily taken into account via a multirate formulation.
ROSSI, MATTEO GIOVANNI, LOVERA, MARCO
openaire   +2 more sources

On the prediction of satellite orbit decay and impact

Conference on Aerospace Meteorology, 1966
Abstract : Presentation of problems associated with predicting satellite orbit decay plus a description of several computer programs for computing long-term orbit decay, model atmospheres, and final decay and re-entry. Computation of long-term orbit decay using the RAND Satellite Lifetime Program is illustrated for Explorer 9, and the orbit-decay data ...
C. GAZLEY, L. ROWELL, G. SCHILLING
openaire   +1 more source

Analytical representations of precise orbit predictions for Earth orbiting space objects

Advances in Space Research, 2017
Abstract Accurate orbits of Earth orbiting space objects are usually generated from an orbit determination/prediction process using numerical integrators, and presented to users in a tabulated form or a state vector including force model parameters. When dealing with hundreds of thousands of space objects such as in the space conjunction assessment ...
Jizhang Sang, Bin Li, Junyu Chen, Pin Zhang, Jinsheng Ning   +4 more
openaire   +1 more source