Results 31 to 40 of about 7,732 (256)

Initial Orbit Determination for the CR3BP using Particle Swarm Optimization

CoRR, 2022
This work utilizes a particle swarm optimizer (PSO) for initial orbit determination for a chief and deputy scenario in the circular restricted three-body problem (CR3BP). The PSO is used to minimize the difference between actual and estimated observations and knowledge of the chief's position with known CR3BP dynamics to determine the deputy's initial ...
David Zuehlke, Taylor Yow, Daniel Posada, Joseph Nicolich, Christopher W. Hays, Aryslan Malik, Troy Henderson   +6 more
openaire   +2 more sources

Research on Sliding-Window Batch Processing Orbit Determination Algorithm for Satellite-to-Satellite Tracking

Aerospace
In response to the increasing demand for high-precision navigation of satellites operating in the cislunar space, this study introduces an onboard orbit determination algorithm considering both convergence and computational efficiency, referred to as the
Yingjie Xu, Xuan Feng, Shuanglin Li, Jinghui Pu, Shixu Chen, Wenbin Wang   +5 more
doaj   +1 more source

On initial orbit determination

The Astronomical Journal, 1984
The classical methods of initial orbit determination are brought together within a larger viewpoint. This new synthesis stresses that all such techniques follow one of three approaches. Either they seek to compute the orbital element set, or its equivalent, by attacking the differential equations of motion (Laplace), the first integrals of the ...
openaire   +1 more source

Numerical behaviour of the Keplerian Integrals methods for initial orbit determination

Icarus, 2022
We investigate the behaviour of two recent methods for the computation of preliminary orbits. These methods are based on the conservation laws of Kepler's problem, and enable the linkage of very short arcs of optical observations even when they are separated in time by a few years.
Óscar Rodríguez, Giovanni F. Gronchi, Giulio Baù, Robert Jedicke   +3 more
openaire   +3 more sources

Angles-Only Initial Orbit Determination of Low Earth Orbit (LEO) Satellites Using Real Observational Data

Journal of Astronomy and Space Sciences, 2019
The Optical Wide-field patroL-Network (OWL-Net) is a Korean optical space surveillance system used to track and monitor objects in space. In this study, the characteristics of four Initial Orbit Determination (IOD) methods were analyzed using artificial ...
Hyewon Hwang, Sang-Young Park, Eunji Lee
doaj   +1 more source

Initial Orbit Determination for Distant Objects

The Astronomical Journal, 2004
Initial orbit determination for distant objects can be made a simple linear problem with explicit solutions. This is similar to stellar parallax work, with very difficult observations but simple computations. A very simple procedure for computing ephemerides for distant objects is proposed.
openaire   +2 more sources

Validation of GPS Based Precise Orbits Using SLR Observations [PDF]

Journal of Astronomy and Space Sciences, 2009
In this study, the YLPODS (Yonsei Laser-ranging Precision Orbit Determination System) is developed for POD using SLR (Satellite Laser Ranging) NP (Normal Point) observations. The performance of YLPODS is tested using SLR NP observations of TOPEX/POSEIDON
Young-Rok Kim, Eunseo Park, Sang-Young Park, Kyu-Hong Choi, Yoola Hwang, Hae-Yeon Kim, Byoung-Sun Lee, Jaehoon Kim   +7 more
doaj   +1 more source

Simulation of the Use of Variance Component Estimation in Relative Weighting of Inter-Satellite Links and GNSS Measurements

Remote Sensing, 2022
Inter-satellite links (ISLs) can improve the performance of the Global Navigation Satellite System (GNSS) in terms of precise orbit determination, communication, and data-exchange capabilities.
Tomasz Kur, Tomasz Liwosz
doaj   +1 more source

Probabilistic Methods for Initial Orbit Determination and Orbit Determination in Cislunar Space

CoRR
In orbital mechanics, Gauss's method for orbit determination (OD) is a popular, minimal assumption solution for obtaining the initial state estimate of a passing resident space object (RSO). Since much of the cislunar domain relies on three-body dynamics, a key assumption of Gauss's method is rendered incompatible, creating a need for a new, minimal ...
Ishan Paranjape, Tarun Hejmadi, Suman Chakravorty   +2 more
openaire   +2 more sources

Clinical, Histopathological, and Molecular Characterization of Pediatric MN1::ZNF341‐Associated Cancer

Pediatric Blood &Cancer, EarlyView.
ABSTRACT A lethal round‐cell malignancy with an MN1::ZNF341 fusion has recently been reported in three infants. Here, we describe four further tumors, three in newborns (including monozygotic twins), and one in an adolescent. Detailed clinical, radiological, and histopathological data differentiate these tumors from their main mimics, neuroblastoma and
Thomas R. W. Oliver, Dyanne Rampling, Barbara Walkowiak, Nathaniel D. Anderson, Manas Dave, Henry Lee‐Six, Sadie Baskind, Pooja Balasubramanian, Glenn Anderson, Conor Parks, Toochi Ogbonnah, Emilia R. Robertson, Simon Hannam, Rohan Verma, John C. Achermann, Liina Palm, Neil Sebire, Thomas Jacques, Tom Watson, Carryl Dryden, Karin Straathof, Mette Jorgensen, Olga Slater, Sam Behjati, Sarita Depani, J. Ciaran Hutchinson   +25 more
wiley   +1 more source