Nonlinear Adaptive Equivalent Control Based on Interconnection Subsystems for Air-Breathing Hypersonic Vehicles by Chaofang Hu, Yanwen Liu

“…The reformulation of the altitude-flight-path angle dynamics and the attack angle-pitch rate dynamics is constructed into interconnection subsystems with input-to-state stability via small-gain theorem. …”
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Parameter Study on Ultraviolet Rayleigh–Brillouin Doppler Lidar with Dual-Pass Dual Fabry–Perot Interferometer for Accurately Measuring Near-Surface to Lower Stratospheric Wind Fie... by Fahua Shen, Zhifeng Shu, Jihui Dong, Guohua Jin, Liangliang Yang, Zhou Hui, Hua Xu

“…The simulation results show that at an altitude of 0–20 km, within the radial wind speed dynamic range of ±50 m/s, the radial wind speed measurement bias caused by aerosol scattering signal is less than 0.17 m/s in the cloudless region; within the radial wind speed dynamic range of ±30 m/s, the bias is less than 0.44 m/s and 0.91 m/s in the simulated cumulus cloud at 4 km where aerosol backscatter ratio <i>R_β</i> = 3.8 and cirrus cloud at 9 km where <i>R_β</i> = 2.9, respectively; using a laser with a pulse energy of 350 mJ and a repetition frequency of 50 Hz, a 450 mm aperture telescope, setting the detection zenith angle of 30°, vertical resolution of 26 m@0–10 km, 78 m@10–20 km, and 260 m@20–30 km, and a time resolution of 1 min, with the daytime sky background brightness taking 0.3 WSr⁻¹m⁻²nm⁻¹@355 nm, the radial wind speed measurement errors of the system during the day and night are below 2.9 m/s and 1.6 m/s, respectively, up to 30 km altitude, below 0.28 m/s at 10 km altitude, and below 0.91 m/s at 20 km altitude all day.…”
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Robust Tracking Control of a Quadrotor UAV Based on Adaptive Sliding Mode Controller by Tianpeng Huang, Deqing Huang, Zhikai Wang, Awais Shah

“…In this paper, a robust adaptive sliding mode control scheme is developed for attitude and altitude tracking of a quadrotor unmanned aerial vehicle (UAV) system under the simultaneous effect of parametric uncertainties and consistent external disturbance. …”
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Migratory Dates, Breeding Phenology, and Reproductive Success of European Turtle Doves between Lowlands and Highest Breeding Habitats in North Africa by Ismail Mansouri, Mohamed Mounir, Wafae Squalli, Laila Elhanafi, Mohamed Dakki, Lahsen El Ghadraoui

“…The migratory time, breeding chronology, and reproductive success of the European turtle doves (Streptopelia turtur) were studied in Midelt as a high-altitude breeding habitat and Beni Mellal as a low-altitude breeding site from 2015 to 2018 in Morocco. …”
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Long-term spatiotemporal features of aerosol optical characteristics and relative humidity in China’s offshore areas by Jie He, Zhao Li, Linyu He, Jian Wang, Weiping Jiang

“…After dividing the China’s offshore waters, the overall optical properties of aerosols decreased in order of the Bohai Sea and Yellow Sea, the East China Sea, and the South China Sea, due to the proportion of marine aerosols increase toward the south. After dividing the altitude layer in the sea area, within the range of 0–7 km, the higher the altitude, the less oceanic aerosols and the more terrestrial aerosols. …”
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Long‐Term Monitoring of Energetic Protons at the Bottom of Earth’s Radiation Belt by K. Yoshioka, Y. Miyoshi, S. Kurita, M. Teramoto, F. Tsuchiya, A. Yamazaki, G. Murakami, T. Kimura, H. Kita, I. Yoshikawa, Y. Kasaba

“…This is because the orbits of satellites that are designed to cover large areas of the magnetosphere are not suitable for long‐term continuous observations at low altitudes. In this study, we focused on data from a space telescope that usually follows a low‐altitude circular orbit. …”
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Malate initiates a proton-sensing pathway essential for pH regulation of inflammation by Yu-jia-nan Chen, Rong-chen Shi, Yuan-cai Xiang, Li Fan, Hong Tang, Gang He, Mei Zhou, Xin-zhe Feng, Jin-dong Tan, Pan Huang, Xiao Ye, Kun Zhao, Wen-yu Fu, Liu-li Li, Xu-ting Bian, Huan Chen, Feng Wang, Teng Wang, Chen-ke Zhang, Bing-hua Zhou, Wan Chen, Tao-tao Liang, Jing-tong Lv, Xia Kang, You-xing Shi, Ellen Kim, Yin-hua Qin, Aubryanna Hettinghouse, Kai-di Wang, Xiang-li Zhao, Ming-yu Yang, Yu-zhen Tang, Hai-long Piao, Lin Guo, Chuan-ju Liu, Hong-ming Miao, Kang-lai Tang

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The Effect of Land-Use Intensity on Surface Temperature in the Dongting Lake Area, China by Wenmin Hu, Weijun Zhou, Hongshi He

“…Human activities produced larger effects in the western region than in the eastern or central region of the study area, according to the observed variations in the centres of gravity for temperature and land-use intensity. (3) The temperature response to land-use intensity changes was more sensitive in low-altitude areas than in high-altitude areas; the response presented a north-south gradient, possibly due to socioeconomic and urbanisation differences.…”
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Observed Sprite Streamer Growth Rates by H. C. Stenbaek‐Nielsen, M. G. McHarg, N. Y. Liu

“…Evaluating the field at 70 km altitude, we find fields of 98 (0.45 Ek), 121 (0.56 Ek), and 188 (0.87 Ek) V/m for the 3 sprite types, indicating that jellyfish sprites are the most energetic. …”
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METHODOLOGY TO IMPROVE THE ACCURACY OF DETERMINING THE POSITION OF UAVS EQUIPPED WITH SINGLE-FREQUENCY RECEIVERS FOR THE PURPOSES OF GATHERING DATA ON AVIATION OBSTACLES by Marta LALAK, Kamil KRASUSKI, Damian WIERZBICKI

“…Low-altitude photogrammetric studies are often applied in detection of aviation obstacles. …”
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Altitudinal distribution and habitat use of the common wall lizard Podarcis muralis (Linnaeus, 1768) and the Horvath’s rock lizard Iberolacerta horvathi (Méhely, 1904) in the Kočev... by Anamarija Žagar

“…Both species occurred across the entire altitudinal span but exhibited an opposite pattern of relative abundances and frequencies, which increased with increasing altitude in Horvath’s rock lizard and with decreasing altitude in common wall lizard. …”
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Types of Accidents and Causes of Their Occurrence in Outdoor Sports: A Conceptual Review by Erdoğan EKİNCİ

“…These risks include drowning, dehydration, poisoning, burn injuries, fires, hypothermia and frostbite, natural disasters, sunstroke, wild animal attacks, and high-altitude sickness. Consequently, it can be said that participants in outdoor sports activities are exposed to a range of risks. …”

Interplay between fecundity, sexual and growth selection on the spring phenology of European beech (Fagus sylvatica L.). by Oddou-Muratorio, Sylvie, Bontemps, Aurore, Gauzere, Julie, Klein, Etienne K

“…The respective intensities of directional and stabilizing selection varied with the environment: at low altitude, directional selection for earlier phenology was modulated by strong assortative mating and by an interaction effect between TBB an size on female fecundity, whereas at high altitude, directional selection for earlier phenology was reinforced by selection through male fecundity. …”
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A Modified Cycle Slip Detection Method with GNSS Doppler Assistance and Optimizing by Adaptive Threshold and Sliding Polynomial Fitting by Kezhao Li, Yunyan Shen, Xiaokui Yue, Yingxiang Jiao, Kai Wang, Zhe Yue, Keke Xu

“…., cycle slips occur in low altitude satellite, low sampling rate of dual-frequency observations. …”
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Potensi Pembangunan Pembangkit Tenaga Mini Hidro (PLTM) pada Sungai Batang Kenaikan Kabupaten Pasaman Barat by Februarman Februarman, Hendri Hardiyanto, Muhamad Shubhi Nurul Hadie

“…Based on the topographic conditions of the location, the elevation of the lighthouse weir is planned at an altitude of +200 m above sea level, the calming tank is at an altitude of +197 m and the location of the power house is at an altitude of +150 m, while the length of the carrier channel is 2400 m. …”
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Alpine vegetation community patterns in the Khumbu region, Nepalese Himalaya by Ruolin Leng, Stephan Harrison, Elizabeth A. Byers, Mahesh Magar, Harkrei Rai, Ram Raj Rijal, Karen Anderson

“…The Himalayan alpine zone (HAZ)—a high-altitude zone above approximately 4,100 m.a.s.l., is projected to experience strong eco-environmental changes with climate change. …”
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Comparison of Empirical and Theoretical Models of the Thermospheric Density Enhancement During the 3–4 February 2022 Geomagnetic Storm by Jianhui He, Elvira Astafyeva, Xinan Yue, Nicholas M. Pedatella, Dong Lin, Timothy J. Fuller‐Rowell, Mariangel Fedrizzi, Mihail Codrescu, Eelco Doornbos, Christian Siemes, Sean Bruinsma, Frederic Pitout, Adam Kubaryk

“…Abstract On 3 February 2022, at 18:13 UTC, SpaceX launched and a short time later deployed 49 Starlink satellites at an orbit altitude between 210 and 320 km. The satellites were meant to be further raised to 550 km. …”
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Spatial Changes in Soil Nutrients in Tea Gardens from the Perspective of South-to-North Tea Migration: A Case Study of Shangluo City by Ziqi Shang, Jichang Han, Yonghua Zhao, Ziru Niu, Tingyu Zhang

“…[Conclusions] The variation in soil nutrients and pH in the tea gardens of Shangluo City is closely associated with altitude and latitude. Notably, there is no discernible trend of pH acidification. …”
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Geochemical Characterization of Spring Waters in the Crati River Basin, Calabria (Southern Italy) by Simona Gaglioti, Ernesto Infusino, Tommaso Caloiero, Giovanni Callegari, Ilaria Guagliardi

“…Additionally, the relationships between water temperature and altitude and electric conductivity (EC) and altitude were assessed. …”
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Identification of bald patches in degraded alpine meadows by UAV-based remote sensing and deep learning by Lu Wang, Lulu Cui, Zihan Song, Min Zheng, Chengyi Li, Xilai Li

“…In summary, the results showed that it is effective to combine low-altitude UAV remote sensing platform with deep learning technology. …”
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