A Miniaturized High-Gain Flexible Antenna for UAV Applications by Xinhuan Yang, Yanzhu Qi, Bo Yuan, Yazi Cao, Gaofeng Wang

“…The results show that the omnidirectional gain fluctuates within 4.5 ± 0.1 dBi in the desired band (902 MHz–928 MHz), which is high enough for the UAV application. …”
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Nonlinear Vibration Analysis of Tubing Strings in Underground Gas Storage Using Multiscale Wavelet Transform by Hang Yan, Yifei Yan, Xiangzhen Yan

“…The tubing string exposed to transient flow may undergo nonlinear vibration due to sudden change in pressure in conveying gas. But, the drag on such structures often leads to fatigue failure of the strings that may significantly affect the vibrations through the combined effects of the first sections of gas injection, annulus pressure, the inclined structures, and the large transient flow component. …”
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RESEARCH ON BLADE RADIUS AND INSTALLATION POSITION OF BI-DIRECTIONAL DIVERSION DEVICE by ZHANG Xin, LI GuoFu

“…Then, by studying the variation law of flow velocity distribution in the vertical direction, obtained the optimal blade installation position. Finally, through the drag experiment, obtained the periodic power generation under the bidirectional water flow. …”
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A Global Thermospheric Density Prediction Framework Based on a Deep Evidential Method by Yiran Wang, Xiaoli Bai

“…Abstract Thermospheric density influences the atmospheric drag and is crucial for space missions. This paper introduces a global thermospheric density prediction framework based on a deep evidential method. …”
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Aerodynamic Load Reduction on a Supercritical Airfoil Using Tilted Microjets by Cheng Xue, Feng Deng, Haifeng Wang, Ning Qin

“…The movement and weakening of the shock due to the jet are observed at α>2∘ in transonic flow, resulting in a drag reduction compared to the baseline airfoil. …”
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Initial Moving Mechanism of Densely-Packed Particles Driven by a Planar Shock Wave by Hua Lv, Zhongqi Wang, Yunming Zhang, Jianping Li

“…We found that before particles show notable motion, shock waves complete reflection and transmission, and stress waves propagate downstream on particle skeleton. …”
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Science Through Machine Learning: Quantification of Post‐Storm Thermospheric Cooling by Richard J. Licata, Piyush M. Mehta, Daniel R. Weimer, Douglas P. Drob, W. Kent Tobiska, Jean Yoshii

“…Results show that density reductions up to 40% can occur 1–3 days post‐storm depending on the location and strength of the storm.…”
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MSIS‐UQ: Calibrated and Enhanced NRLMSIS 2.0 Model With Uncertainty Quantification by Richard J. Licata, Piyush M. Mehta, Daniel R. Weimer, W. Kent Tobiska, Jean Yoshii

“…Instead of providing point estimates, our model (called MSIS‐UQ) outputs a distribution which is assessed using a metric called the calibration error score. We show that MSIS‐UQ debiases NRLMSIS 2.0 resulting in reduced differences between model and satellite density of 25% and is 11% closer to satellite density than the Space Force's High Accuracy Satellite Drag Model. …”
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The Aerodynamic Characteristics of a Diamond Joined-Wing Morphing Aircraft by Shuai Miao, Xiaoyong Ma, Cheng Chen, Binhua He, Yong Huang

“…Compared with traditional morphing aircraft, the main advantages of this configuration include better transonic and supersonic performance, better lift characteristics in the state of a high-aspect ratio, and lower zero-lift drag in the supersonic state. The lift ratio of the front and rear wings shows a good similarity at different Mach numbers, especially for the 15° model, and the value eventually tends to be 1.3 at α=12°. …”
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Tuning Wetting Properties Through Surface Geometry in the Cassie–Baxter State by Talya Scheff, Florence Acha, Nathalia Diaz Armas, Joey L. Mead, Jinde Zhang

“…Superhydrophobic coatings are beneficial for applications like self-cleaning, anti-corrosion, and drag reduction. In this study, we investigated the impact of surface geometry on the static, dynamic, and sliding contact angles in the Cassie–Baxter state. …”
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Rectification effects of regional air–sea interactions over western boundary current on large-scale sea surface temperature and extra-tropical storm tracks by Lionel Renault, Thomas Arsouze, Fabien Desbiolles, Justin Small

“…CFB causes eddy-killing by drag friction between currents and the atmosphere. …”
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Statistical Characterization of GITM Thermospheric Horizontal Winds in Comparison to GOCE Estimations by Daniel A. Brandt, Aaron J. Ridley

“…Discrepancies in GITM's performance may be explained by inaccurate modeling of ion drift, ion drag, and electron densities.…”
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Machine‐Learned HASDM Thermospheric Mass Density Model With Uncertainty Quantification by Richard J. Licata, Piyush M. Mehta, W. Kent Tobiska, S. Huzurbazar

“…Three input sets are also tested, showing improved performance when introducing time histories for geomagnetic indices. …”
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TIE‐GCM ROPE ‐ Dimensionality Reduction: Part I by Piyush M. Mehta, Richard J. Licata

“…Abstract Physics‐based models of the ionosphere‐thermosphere system have been touted as the next big thing in the context of drag modeling and space operations for decades. However, the computational complexity of such models have primarily kept them being used operationally. …”
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Solar EUV‐Enhancement and Thermospheric Disturbances by C. Briand, K. Doerksen, F. Deleflie

“…The duration of this plateau is long enough that it may be important for estimating satellite drag. Over the duration of the EUV‐enhancements, Dst drops are also observed, indicating ring current activity. …”
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Research on an Aerial Docking Strategy for Meta-UAVs Using Aerodynamic Data Surrogate Models by Kangwen Sun, Yixiang Gao, Zhiyao Wang, Haoquan Liang, Chenxuan Zhao, Xinzhe Ji

“…Optimization of the docking process, focusing on impulse and moment of impulse, is achieved using a greedy algorithm. The results show a reduction in drag impulse and rolling moment by 10.89% and 15.76%, respectively, thereby easing the burden on the control system of UAVs.…”
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Vibration and Performance Analyses Using Individual Blade Pitch Controls for Lift-Offset Rotors by Jae-Sang Park, Do-Hyung Kim, Sanghyun Chae, Ye-Lin Lee, Jeong-In Go

“…This study shows that the hub vibration of the lift-offset rotor in high-speed flight can be reduced significantly but the rotor performance increases slightly, using the IBC with multiple harmonic inputs.…”
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Numerical Study of the Aerodynamic Effect of Ski Suit Surface Roughness on Ski Jumping Athletes During the Flight Phase by K. Liu, Z. Wang, Q. Liu

“…Specifically, the lift-drag ratio of the entire multibody system shows a trend of increasing first and then decreasing. …”
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Omnidirectional Motion Trajectory Tracking Control Method for AUVs by Jiangpeng XU, Junlei WANG, Yi TANG

“…The method retained the original low-drag streamlined torpedo-like structural design and motion mode of AUVs while endowing them with a new omnidirectional motion mode. …”
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Energetically Consistent Eddy‐Diffusivity Mass‐Flux Convective Schemes: 1. Theory and Models by M. Perrot, F. Lemarié, T. Dubos

“…We demonstrate that when using an EDMF scheme, closed energy budgets can be recovered if: (a) bulk production terms of turbulent kinetic energy (TKE) by shear buoyancy include MF contributions; (b) boundary conditions are consistent with EDMF, to avoid spurious energy fluxes at the boundary. Furthermore, we show that lateral mixing, due to either entrainment or detrainment induces a net production of TKE via the shear term, with enhanced production under increased horizontal drag. …”
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