Results 31 to 40 of about 2,132 (298)

5G NB-IoT via low density LEO Constellations

, 2021
5G NB-IoT is seen as a key technology for providing truly ubiquitous, global 5G coverage (1.000.000 devices/km2) for machine type communications in the internet of things. A non-terrestrial network (NTN) variant of NB-IoT is being standardized in the 3GPP, which along with inexpensive and non-complex chip-sets enables the production of competitively ...
Sørensen, René Brandborg, Møller, Henrik Krogh, Koch, Per   +2 more
openaire   +3 more sources

A Performance Study on the Combination of Available GNSS and Potential LEO-PNT Constellations

IEEE Access
With the reduction in the launch and manufacturing costs of satellites, there has been a surge of interest in Low-Earth Orbit (LEO) satellites from both the industrial and academic sectors in recent years.
Kaan Celikbilek, Elena Simona Lohan
doaj   +1 more source

Cross-Domain Fusion Constellation Design of Communication, Navigation and Remote Sensing

Applied Sciences, 2023
Low earth orbit (LEO) mega-constellations have once again triggered a wave of space-based system construction. On the one hand, LEO communication, LEO navigation, LEO remote sensing constellations and so on are proposed.
Junxiang Qin, Xuan Li, Xiaotian Ma, Xiye Guo, Jun Yang   +4 more
doaj   +1 more source

LEO constellation optimization for LEO enhanced global navigation satellite system (LeGNSS)

Advances in Space Research, 2020
Abstract Low Earth Orbit (LEO) enhanced Global Navigation Satellite System (LeGNSS) has been recognized as the promising positioning system in the near future where mega-constellations of LEO satellites are used for precise positioning. Fast Precise Point Positioning (PPP) convergence can be achieved if LEO constellations are employed into current ...
Haibo Ge, Bofeng Li, Liangwei Nie, Maorong Ge, Harald Schuh   +4 more
openaire   +3 more sources

Mechanisms of IgE‐mediated food allergy and the role of allergen‐specific B cells

FEBS Letters, EarlyView.
Food allergy arises when allergen‐specific B cells preferentially produce immunoglobulin E (IgE) antibodies against harmless foods. This article explains the mechanisms driving IgE‐mediated reactions, highlights the central role of these B cells, and discusses how natural tolerance (NT) and oral immunotherapy (OIT) can reshape allergic immune responses.
Juan‐Felipe López, Özge Yilmaz Ardicli, Mübeccel Akdis   +2 more
wiley   +1 more source

Acoustic Measures Capture Speech Dysfunction in Spinocerebellar Ataxia

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Spinocerebellar ataxias (SCA) are hereditary cerebellar degenerative disorders with a common feature of dysarthria, involving impaired phonatory and articulatory control of speech, thereby affecting social communication. In this study, we investigated whether acoustic measures could objectively measure speech dysfunction and identify
Zena Fadel, Charlotte Hennessey, Hannah Lee, Pia Parekh, Sheng‐Han Kuo, Ami Kumar   +5 more
wiley   +1 more source

Navigation Resource Allocation Algorithm for LEO Constellations Based on Dynamic Programming

Remote Sensing
Navigation resource allocation for low-earth-orbit (LEO) constellations refers to the optimal allocation of navigational assets when the number and allocation of satellites in the LEO constellation have been determined.
Sixin Wang, Xiaomei Tang, Jingyuan Li, Xinming Huang, Jiyang Liu, Jian Liu   +5 more
doaj   +1 more source

Performance of GNSS Global Ionospheric Modeling Augmented by LEO Constellation

Earth and Space Science, 2020
The Low‐Earth‐Orbiting (LEO) satellite has a fast motion and thus contributes to rapid changes in satellite geometric distribution, which can effectively mitigate multipath effects and offer more available observations.
Xiaodong Ren, Xiaohong Zhang, Michael Schmidt, Zhibo Zhao, Jun Chen, Jincheng Zhang, Xingxing Li   +6 more
doaj   +1 more source

The Impact of High‐Productivity Processing on the Fatigue Failure of an Additive Manufactured Superalloy HAYNES 282

Advanced Engineering Materials, EarlyView.
The low cycle fatigue life of additive manufactured HAYNES® 282® superalloy was investigated for conventional and high‐productivity processing: samples of the former lasted 1400–1700 cycles, while samples of the latter failed at ~ 1200 cycles, at 760 °C and 1% strain.
Abdul Shaafi Shaikh, Ahmed Fardan, Tatiana Mishurova, Eduard Hryha   +3 more
wiley   +1 more source

Analysis of Multipath Code-Range Errors in Future LEO-PNT Systems

Engineering Proceedings, 2023
In recent years, low-Earth-orbit (LEO) constellations have been proposed for Positioning, Navigation and Timing (PNT) applications. Moreover, a couple of test satellites have already been launched and many more are scheduled in the near future.
Sibren De Bast, Jean-Marie Sleewaegen, Wim De Wilde   +2 more
doaj   +1 more source