To solve the real-time complex mission-planning problem for Multiple heterogeneous Unmanned Aerial Vehicles (UAVs) in the dynamic environments, this paper addresses a new approach by effectively adapting the Consensus-Based Bundle Algorithms (CBBA) under the constraints of task timing, limited UAV resources, diverse types of tasks, dynamic addition of tasks, and real-time requirements. We introduce the dynamic task generation mechanism, which satisfied the task timing constraints. The tasks that require the cooperation of multiple UAVs are simplified into multiple sub-tasks to perform by a single UAV independently. We also introduce the asynchronous task allocation mechanism. This mechanism reduces the computational complexity of the algorithm and the communication time between UAVs. The partial task redistribution mechanism has been adopted for achieving the dynamic task allocation. The real-time performance of the algorithm is assured on the premise of optimal results. The feasibility and real-time performance of the algorithm are validated by conducting dynamic simulation experiments.

An orbital head of orbital forging press with double eccentric sleeve has four types of movement, but most workpieces are formed by circular movement. The motion equation is established according to the structure and the movement principle of orbital head. Then find that the rotational speed of inner and outer eccentric sleeves simply affects the rotation period of orbital head in circle and straight line movements, and not only affects the rotation period but also the movement shape in spiral and rose curve movements. The eccentricity of inner and outer eccentric sleeves can change the shape and size of the movement, adjust the distance from the movement to the center point, and change straight line movement into ellipse, spiral and rose curve movements do not cross through the center. It can solve the problem that straight line, spiral and rose curve movements pass the center, orbital angle is zero and the forming force increases sharply, achieve the continuous local deformation of workpiece during the forming process.

The analysis of light variation of M87 can help us understand the disc evolution. In the past decade, M87 has experienced several short-term light variabilities related to flares. We also find there are year-scale X-ray variations in the core of M87. Their light variability properties are similar to clumpy-ADAF. By re-analyzing 56 Chandra observations from 2007 to 2019, we distinguish the ‘non-flaring state’ from ‘flaring state’ in the light variability. After removing flaring state data, we identify 4 gas clumps in the nucleus and all of them can be well fitted by the clumpy-ADAF model. The average mass accretion rate is ∼ 0.16M⊙yr−1. We analyze the photon index(Γ) — flux(2-10keV) correlation between the non-flaring state and flaring state. For the non-flaring states, the flux is inversely proportional to the photon index. For the flaring states, we find no obvious correlation between the two parameters. In addition, we find that the flare always occurs at a high mass accretion rate, and after the luminosity of the flare reaches the peak, it will be accompanied by a sudden decrease in luminosity. Our results can be explained as that the energy released by magnetic reconnection destroys the structure of the accretion disc, thus the luminosity decreases rapidly and returns to normal levels thereafter.

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