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This paper aims to present numerical simulations for a series of flight processes for the postlaunching stage of the “balloon-borne UAV system.” It includes the balloon further ascent motion after airborne launching. In terms of unmanned aerial vehicles (UAVs), the tailspin state and the charge-out process with an anti-tailspin parachute-assisted suspending are analyzed. Then, the authors conduct trajectory optimization simulations for the long-distance gliding process.

The balloon kinematics model and the parachute Kane multibody dynamic model are established. Using steady-state tailspin to reduced-order analysis and achieving change-out simulation by parachute suspension dynamic model. A reentry optimization control problem is developed and the Radau pseudo-spectral method is used to calculate the glide trajectory.

The established dynamic model and trajectory optimization method can effectively simulate the motion process of balloons and UAVs. The system mass reduction for launching UAVs will not cause damage to the balloon structure. The anti-tailspin parachute can reduce the UAV attack angles effectively. The UAV can glide to the designated target position by adjusting the attack angle and sideslip angle. The farthest flight distance after launching from 20 km height is 94 km and the gliding time is 40 min, which demonstrates the potential application advantage of high-altitude launching.

The research content and related conclusions of this article achieve a closed-loop analysis of the flight mission chain for the “balloon-borne UAV system,” which provides simulation references for relevant balloon launching experiments.

This paper establishes a complete set of numerical simulation models and can effectively analyze various postlaunching behaviors.

One of the standard practices of Communist Parties around the world is to employ art, including music, as a channel to spread political ideologies. This study aims to scrutinize the reception of Beethoven's music, particularly from a political viewpoint, by the Chinese Communist Party (CCP) in the People's Republic of China (PRC) during the early years of its rule, i.e. from 1949–1959. The ambiguity of Beethoven's own political outlook may have provided an opportunity for the CCP to choose the composer and his music in support of its aims.

To understand why and how the CCP could exploit Beethoven and his music to support its political ideologies, a series of Chinese writings on Beethoven between 1949 and 1959 have been studied. Those literatures not only helped the composer gain reputation and popularity in the PRC, but also provided a platform for the CCP to manipulate such candidate and his music. Finally, the reception of the performances of the Ninth Symphony in 1959 in the PRC is singled out for close examination.

During the first ten years of the establishment of the PRC, the quantity and quality of the articles on Beethoven expanded considerably. These writings continued to reflect the reception of Beethoven and his music with the addition of political nuances that could be interpreted in the CCP's favour.

This paper seeks to examine the PRC's artistic policies, with a particular emphasis on the reception of Beethoven and western classical music.