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Low temperature is a major driver of the upper distributional limits of subtropical evergreen broadleaved forests in East Asia. The eco‐physiology of evergreen broadleaved trees at the upper limits could respond to both lower winter temperature and lower averaged annual temperature that covary with elevation. To analyze these responses, we assessed the variations in leaf chemical traits of Cyclobalanopsis gracilis with seasonality and along elevation in the ecotone from subtropical to temperate climate, and analyzed the relationships between traits of mature leaves and temperature. The study showed that the mass‐based nonstructural carbohydrate (NSC) content reached the highest level across elevations during winter; however, the winter NSC content did not differ between elevations. For mature leaves, leaf dry mass per area (LMA) tended to be higher approaching the upper limit. The leaf carbon to phosphorus ratio (C/P) showed an increasing trend with decreasing temperature, as did leaf carbon to nitrogen ratio (C/N) to some extent. The mass‐based P content showed a decreasing trend approaching the upper limit, whereas area‐based P content showed no significant variation. Our main results indicate that leaf NSC content is highest at all elevations in winter, and individuals at high elevations have high LMA and high nutrient use efficiency. The results suggest that for C. gracilis, an increasing leaf NSC results in a baseline protection to cope with cold in winter, which, at higher elevations is supplemented with increasing LMA and nutrient use efficiency to cope with associated low‐temperature stress.

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Insect-like flapping-wing aircraft is a research focus in the study of Micro Aerial Vehicle. In the paper, a cicada is chosen as the object, and based on the analysis of its wing, its kinematics and three-dimensional model are researched. In the study of kinematics, two softwares (Movias-pro and Photoshop) are applied, and the laws of flap and torsion movements are obtained. In the study of three-dimensional mode, the wing is scanned by the use of flat plane scanning method, and the resulting picture is vectorized. Based on the wing datum, the three-dimensional model of wing is created by the use of Pro/E. The result from the paper lays foundation for the development of cicada-like flapping-wing aircraft.

Tractor SX4187NT361K, which is manufactured by the Shaanxi Automobile Group Limited Corporation, is regarded as a prototype vehicle. This paper investigates an 1/4 car model with air springs for the tractor and a working model of air spring. A height PID control method for ECAS is designed, and its digital simulation is conducted. An ECAS test-bed is designed, and hardware of a measurement and control system for the test-bed is designed with DSPACE system, its softwares are also designed with Simulink and ControlDesk. Finally, active and passive tests of the ECAS are conducted through changing frequencies and desired heights, simulation and test results show that the PID height control method for ECAS is feasible.

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