Solar Tracking Error Analysis of Fresnel Reflector by Jiantao Zheng, Junjie Yan, Jie Pei, Guanjie Liu

“…The tracking error caused by other deviations such as rotating eccentric, latitude, and solar altitude was positive at morning, negative at afternoon, and zero at a certain moment of noon.…”
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Experiences with the GPS in Unstabilized CubeSat by Pavel Kovar

“…Lucky-7 is a private 1U technological CubeSat with power budget 1 W that operates on the quasisynchronous polar orbit at altitude 520 km. One of its scientific missions is to test the operation of GPS. …”
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Quadcopter Aggressive Maneuvers along Singular Configurations: An Energy-Quaternion Based Approach by Ayman A. El-Badawy, Mohamed A. Bakr

“…Energy-based control is utilized to overcome the uncontrollability of the quadcopter at physical singular configurations, for instance, when commanding the quadcopter to gain altitude while pitched at 90∘. Three looping strategies (circular, clothoidal, and newly developed constant thrust) are implemented on a nonlinear model of the quadcopter. …”
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Performance analysis of a satellite–multi-terrestrial relay network with hardware impairments using switch-and-stay combining scheme by Kefeng Guo, Bangning Zhang, Yuzhen Huang, Daoxing Guo

“…Space information networks are proposed to broaden the observation area and realize continuous information acquisition using satellites and high-altitude platform stations. Space information networks are able to enhance detection and transmission capabilities compared to the current single Earth observation satellite. …”
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Research on multi-UAV energy consumption optimization algorithm for cellular-connected network by Jingming XIA, Yufeng LIU, Ling TAN

“…In complex time-varying environment, the ground base station (GBS) may not assist the UAV.Therefore, a mobile edge computing (MEC) cellular-connected network based on digital twin (DT) technology was studied.Given the efficiency of multi-UAV, multiple high-altitude balloon (HAB) equipped with MEC servers were introduced.On this basis, an energy minimization problem for all UAV was proposed, and a multi-UAV trajectory optimization and resource allocation scheme was presented to solve it.The double deep Q-network (DDQN) was applied to handle the association between multi-UAV and multi-HAB, and the multi-UAV trajectory and computing resource allocation were jointly optimized by the successive convex approximation (SCA) and the block coordinate descent (BCD).Simulation experiments verify the feasibility and effectiveness of the proposed algorithm.The system energy consumption is reduced by 30%, better than the comparison algorithms.…”
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Aeroengine High-Attitude/Low Mach Number Oscillations: Mechanism and Prevention Design by Jiqiang Wang

“…The issue of aeroengine oscillations over high-attitude and low-speed flight envelope has been an unsolved problem due to their classified nature and hard reproduction in simulated altitude test stand. Efforts have been sought for either structural integrity or component damage. …”
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ふるさとの暮らしとつながる五感の風景 by Tanaka Naoto 田中尚人

“…Two case studies focus on the need to change this relationship between a local community and its landscapes through the protection of the cultural landscapes of an agricultural plateau of medium altitude. The plateau in question is the Shiraito plateau on the island of Kyūshū where the relationship between the landscape and local communities was disrupted during the disastrous Kumamoto earthquakes in 2016.…”
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Temporal Activity Patterns of the Spider Wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae) in a Disturbed Lower Montane Rainforest (Manizales, Colombia) by Carlos Restrepo-Giraldo, Juanita Rodriguez, James P. Pitts

“…We studied the temporal activity pattern of the spider wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae) in a disturbed lower montane rainforest, which is located in the city of Manizales, Colombia, at an altitude of 2,150 m. Females of this species are diurnal with two peaks of activity: one in the morning and the other in the afternoon. …”
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New Index to Characterize Ionospheric Irregularity Distribution by Endawoke Yizengaw

“…Abstract Characterization of the global ionospheric irregularities as a function of local time, longitude, altitude, and magnetic activities is still a challenge for radio frequency operations, especially at the low‐latitude region. …”
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Les représentations du risque avalancheux chez les pratiquants d’activités récréatives hivernales du Massif vosgien by Florie Giacona, Frédérick Guyon

“…Whereas numerous studies questioned the risk concept in France, few so far focused on medium-high altitude avalanches, even though those occur on a regular basis. …”
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Design and Simulation of Eight-Rotor Unmanned Aerial Vehicle Based on Hybrid Control System by Xueqiang Shen, Jiwei Fan, Haiqing Wang

“…In order to control the position and attitude of unmanned aerial vehicle (UAV) better in different environments, this study proposed a hybrid control system with backstepping and PID method for eight-rotor UAV in different flight conditions and designed a switching method based on altitude and attitude angle of UAV. The switched process of hybrid controller while UAV taking off, landing, and disturbance under the gust is verified in MATLAB/Simulink. …”
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Influence of wind disturbances and nonlinearities of servo drive on the contour of stabilization of the flight of height of unmanned aerial vehicle by V. A. Malkin, I. V. Rozhkov, A. A. San’ko

“…The reaction of the contour of the UAV flight altitude stabilization to the wind is considered, taking into account the nonlinearity of the servo drive elements. …”
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Hepcidin: A Critical Regulator of Iron Metabolism during Hypoxia by Korry J. Hintze, James P. McClung

“…Hypoxia has profound effects on iron absorption and results in increased iron acquisition and erythropoiesis when humans move from sea level to altitude. The effects of hypoxia on iron balance have been attributed to hepcidin, a central regulator of iron homeostasis. …”
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Les mouvements de masse à Noël dans les Alpes italiennes by Marta Chiarle, Costanza Morino, Giovanni Mortara, Walter Alberto, Mario Ravello, Aristide Franchino, Giuseppe Orombelli, Marco Giardino, Luigi Perotti, Guido Nigrelli

“…En hiver, les mouvements de masse à haute altitude sont rares dans les Alpes italiennes, mais sont généralement de plus grande ampleur que ceux qui se produisent en d’autres saisons. …”
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Right ventricular strain impairment due to hypoxia in patients with COPD: a post hoc analysis of two randomised controlled trials by Konrad E Bloch, Mona Lichtblau, Silvia Ulrich, Felix C Tanner, Talant Sooronbaev, Maamed Mademilov, Michael Furian, Helga Preiss, Laura Mayer, Simon Rafael Schneider, Julian Müller, Stephanie Saxer, Anna Titz, Anwer Shehab, Lena Reimann

“…Previous studies in patients with chronic obstructive pulmonary disease (COPD) exposed to hypobaric hypoxia have shown an increase in PAP, while traditional echocardiographic parameters revealed only minimal changes at high altitude. Speckle-tracking-derived analysis is potentially more sensitive to assess right ventricular (RV) function and we used this method to investigate the impact on RV function of patients with COPD ascending to high altitude and compared the results with the traditional echocardiographic parameters.Methods This post hoc analysis evaluates echocardiographic RV free wall strain (RVFWS) in patients with COPD GOLD grade 1–3 travelling from 760 m to 3100 m for a 2-day stay. …”
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Factors influencing hepatitis B vaccination intention and behavior among college students in Tibet: Insights from the expanded theory of planned behavior by Qi Chen, Jun Ma, Ruipeng Wu, Yingting Wang, Xiaoxin Ma, Xiaolei Zheng, Hui Jin

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Changes in the Alpine environment by Philippe Schoeneich, Carmen de Jong

“…State funding often prioritises polar research at the expense of high altitude areas, whereas funding schemes from bodies such as Interreg do not sufficiently address the need for fundamental research, which is nevertheless a necessary first step prior to establishing scenarios. …”
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Reception Centres Above.The Mountain, Emblem of the Paradox of the Integration of Asylum Seekers in Switzerland by Viviane Cretton

“…It focuses on their experiences while they are accommodated in collective reception centres at high altitudes. At the level of Swiss society, asylum seekers are subject to an « integration » injunction, despite the uncertain outcome of their application. …”
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Spatiotemporal Distribution of Dissolved Oxygen in Surface Water in China Based on GIS Technology by WANG Shujuan, MA Yue, WANG Erlei, YAO Weigang, WU Qiong, GU Zhujun

“…In addition to geographical factors such as altitude and temperature, the distribution of dissolved oxygen is positively correlated with pH, total nitrogen, chemical oxygen demand, permanganate index, and five-day biochemical oxygen demand, but negatively correlated with water temperature, total phosphorus, and ammonia nitrogen. …”
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Le lien entre le paysage des cinq sens (gokan no fūkei 五感の風景) et la vie quotidienne du furusato by Tanaka Naoto

“…Two case studies focus on the need to change this relationship between a local community and its landscapes through the protection of the cultural landscapes of an agricultural plateau of medium altitude. The plateau in question is the Shiraito plateau on the island of Kyūshū where the relationship between the landscape and local communities was disrupted during the disastrous Kumamoto earthquakes in 2016.…”
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