Results 81 to 90 of about 31,908 (302)

Vibration and Modal Analysis of Low Earth Orbit Satellite

open access: yesShock and Vibration, 2014
This paper presents design, modeling, and analysis of satellite model used for remote sensing. A detailed study is carried out for the design and modeling of the satellite structure focusing on the factors such as the selection of material, optimization ...
Asif Israr
doaj   +1 more source

Autonomous Formation Flying in Low Earth Orbit [PDF]

open access: yes, 2010
Formation flying is commonly identified as the collective usage of two or more cooperative spacecraft to exercise the function of a single monolithic virtual instrument. The distribution of tasks and payloads among fleets of coordinated smaller satellites offers the possibility to overcome the classical limitations of traditional single-satellite ...
openaire   +3 more sources

Low Earth Orbiting (LEO) Satellite and Orbital Decay

open access: yesInternational Journal of Engineering and Advanced Technology, 2022
In this article we present a simple but elegant numerical calculation to study the motion of a low earth orbiting (LEO) satellite in gravitational potential and under the influence of quadratic drag force. We solve a set of coupled differential equations to calculate the instantaneous position and velocity of the satellite and calculate the change in ...
openaire   +1 more source

Somatic mutational landscape in von Hippel–Lindau familial hemangioblastoma

open access: yesMolecular Oncology, EarlyView.
The causes of central nervous system (CNS) hemangioblastoma in Von Hippel–Lindau (vHL) disease are unclear. We used Whole Exome Sequencing (WES) on familial hemangioblastoma to investigate events that underlie tumor development. Our findings suggest that VHL loss creates a permissive environment for tumor formation, while additional alterations ...
Maja Dembic   +5 more
wiley   +1 more source

Standalone GPS L1 C/A Receiver for Lunar Missions

open access: yesSensors, 2016
Global Navigation Satellite Systems (GNSSs) were originally introduced to provide positioning and timing services for terrestrial Earth users. However, space users increasingly rely on GNSS for spacecraft navigation and other science applications at ...
Vincenzo Capuano   +7 more
doaj   +1 more source

Extension of earth orbits using low-thrust propulsion

open access: yes, 2010
The primary motivation for the utilization of space for environmental science, and in-particular Earth Observation, is the unique vantage point which a spacecraft can provide.
Anderson, Pamela, Macdonald, M.
core  

CD47 promotes mitogen‐activated protein kinase and epithelial‐to‐mesenchymal transition molecular programs to drive prometastatic phenotypes in non‐small cell lung cancer

open access: yesMolecular Oncology, EarlyView.
Beyond its role in immune evasion, this study identified that CD47 drives tumor‐intrinsic signaling in non‐small cell lung cancer (NSCLC). Transcriptomic profiling and functional studies revealed that CD47 regulates cell adhesion, migration, and metastasis through an ERK–EMT signaling axis.
Asa P.Y. Lau   +8 more
wiley   +1 more source

Generation of optimal trajectories for Earth hybrid pole sitters [PDF]

open access: yes, 2011
A pole-sitter orbit is a closed path that is constantly above one of the Earth's poles, by means of continuous low thrust. This work proposes to hybridize solar sail propulsion and solar electric propulsion (SEP) on the same spacecraft, to enable such a ...
Colin R. McInnes   +5 more
core   +1 more source

Heterozygous loss‐of‐function alleles associate the conserved 3′‐5′ exoribonuclease EXOSC10 with hypersensitivity to the anticancer drug 5‐fluorouracil

open access: yesMolecular Oncology, EarlyView.
EXOSC10, an essential nuclear RNA exosome‐associated 3′‐5′ exoribonuclease, is inhibited by the anticancer drug 5‐fluorouracil (5‐FU), and EXOSC10 depletion increases 5‐FU sensitivity. The colon‐cancer variant EXOSC10S402T, located in a proteolysis motif, is stable and nuclear but nonfunctional in vivo.
Radhika Sain   +10 more
wiley   +1 more source

Enhanced Real-Time Onboard Orbit Determination of LEO Satellites Using GPS Navigation Solutions with Signal Transit Time Correction

open access: yesAerospace
Enhanced real-time onboard orbit determination for low-Earth-orbit satellites is essential for autonomous spacecraft operations. However, the accuracy of such systems is often limited by signal propagation delays between GPS satellites and the user ...
Daero Lee, Soon Sik Hwang
doaj   +1 more source

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