Results 51 to 60 of about 1,971 (165)

Dynamic analysis of the tethered satellite system considering uncertain but bounded parameters

Defence Technology
Dynamic analysis of the tethered satellite system (TSS) can provide a fundamental guideline to the evaluation of performance and robust design of the system examined.
Xin Jiang, Zhengfeng Bai
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Satellite-based analysis of ocean-surface stress across the ice-free and ice-covered polar oceans [PDF]

Earth System Science Data
Ocean-surface stress is a critical driver of polar sea-ice dynamics, air–sea interactions, and ocean circulation. This work provides a daily analysis of ocean-surface stress on 25 km Equal-Area Scalable Earth (EASE) grids across the ice-free and ice ...
C. Liu, C. Liu, L. Yu
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Model and Dynamic Analysis of a Three-Body Tethered Satellite System in Three Dimensions

Applied Sciences
The three-body tethered satellite system is a new potential technology for the purposes of orbital transportation. In contrast to conventional orbit transfer methods, this system is expected to transport space supplies to a predetermined orbital altitude
Teng He, ZhanXia Zhu
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Putting It All Together: Adding Value to the Global Ocean and Climate Observing Systems With Complete Self-Consistent Ocean State and Parameter Estimates

Frontiers in Marine Science, 2019
In 1999, the consortium on Estimating the Circulation and Climate of the Ocean (ECCO) set out to synthesize the hydrographic data collected by the World Ocean Circulation Experiment (WOCE) and the satellite sea surface height measurements into a complete
Patrick Heimbach, Patrick Heimbach, Patrick Heimbach, Ichiro Fukumori, Christopher N. Hill, Rui M. Ponte, Detlef Stammer, Carl Wunsch, Carl Wunsch, Jean-Michel Campin, Bruce Cornuelle, Ian Fenty, Gaël Forget, Armin Köhl, Matthew Mazloff, Dimitris Menemenlis, An T. Nguyen, Christopher Piecuch, David Trossman, Ariane Verdy, Ou Wang, Hong Zhang   +21 more
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The Maintenance of Orbital States in a Floating Partial Space Elevator Using the Reinforcement Learning Method

Aerospace
A partial space elevator (PSE) is a multi-body tethered space system in which the main satellite, typically an ultra-large spacecraft or a space station in a higher orbit, is connected to a transport spacecraft in a lower orbit via a tether, maintaining ...
Weili Xu, Xuerong Yang, Gefei Shi
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Aerosol‐Cloud Interactions Near Cloud Base Deteriorating the Haze Pollution in East China

Geophysical Research Letters
Atmospheric aerosols not only cause severe haze pollution, but also affect climate through changes in cloud properties. However, during the haze pollution, aerosol‐cloud interactions are not well understood due to a lack of in situ observations.
Ximeng Qi, Caijun Zhu, Liangduo Chen, Xuguang Chi, Jiaping Wang, Guangdong Niu, Shiyi Lai, Wei Nie, Yannian Zhu, Xin Huang, Tom V. Kokkonen, Tuukka Petäjä, Veli‐Matti Kerminen, Markku Kulmala, Aijun Ding   +14 more
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RNA targeting and cleavage by the type III-Dv CRISPR effector complex

Nature Communications
CRISPR-Cas are adaptive immune systems in bacteria and archaea that utilize CRISPR RNA-guided surveillance complexes to target complementary RNA or DNA for destruction1–5.
Evan A. Schwartz, Jack P. K. Bravo, Mohd Ahsan, Luis A. Macias, Caitlyn L. McCafferty, Tyler L. Dangerfield, Jada N. Walker, Jennifer S. Brodbelt, Giulia Palermo, Peter C. Fineran, Robert D. Fagerlund, David W. Taylor   +11 more
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Long-Duration Inspection of GNSS-Denied Environments with a Tethered UAV-UGV Marsupial System

Drones
Unmanned Aerial Vehicles (UAVs) have become essential tools in inspection and emergency response operations due to their high maneuverability and ability to access hard-to-reach areas. However, their limited battery life significantly restricts their use
Simón Martínez-Rozas, David Alejo, José Javier Carpio, Fernando Caballero, Luis Merino   +4 more
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ANCF-based dynamic modeling and control of an active tethered space robot in approaching phase

Scientific Reports
Herein we analyze the dynamic behavior of a tethered space robot (TSR) for on-orbit capturing, considering large deformation of the tether. The robot is deployed from the mother satellite by using a long, flexible tether and moving along the target ...
Ali Kasiri, Farhad Fani Saberi
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Tether length control for orbital transfer of tethered satellite

Tether length control for orbital transfer of tethered satellite
本研究では、赤道面内におけるテザー衛星の軌道変換について研究する。非線形制御の手法を用いることにより、指定された軌道上位置でシステムの状態を所望の値にするテザー長の履歴を作成する方法を提案する。テザー長を制御することになるピッチ角運動量の制御、ピッチ角速度の制御、ピッチ角の制御、という3つのステップにより、1つの入力で3つの状態を制御する。提案する手法は、数値反復計算を必要としないだけでなく、テザー張力などの物理的拘束にも対応できる。また、システムの状態を正確に目標値に一致させることができる。 This study discusses orbital transfer of a tethered satellite system in equatorial plane.
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