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Maritime moving targets continuation observation has important implications to maintain the safety of the navigation barrier. Existing methods either rely on satellite observations, or only rely on UAV observations. Even though the two cooperative observations, it confined to a simple task allocation. They did not solve the problem of maritime moving targets continuation observation. On the basis of difference between satellites observation and UAV observation, we constructed the aerospace collaborative continuation observation model for maritime moving target, and put forward aerospace collaborative continuation observation strategy (ACCOS) to reduce the complexity of solving the model. According to the spatial and temporal characteristics of the task, ACCOS extracted five sub problems to solve the model: Satellite planning, UAV flight plan, UAV observation sequence, target potential area and distribution probability density prediction, UAV path planning. In order to realize the optimization goal of the model, the five sub problems are modelled and solved in turn. Finally, the simulation results show that the proposed method can greatly reduce the average observation period of the target, and effectively solve the problem of the continuous observation of maritime moving target.

Objective: Reactive oxygen species (ROS) are the essential mechanism involving in the ischemic process. Due to their complex characteristics, the precise effects of ROS on post-ischemic neurons remain uncertain. This study aimed to investigate the potential role of ROS in brain ischemia. Methods: Dynamic ROS levels in the perifocal cortex were evaluated after right middle cerebral artery occlusion (MCAO) of SD rats. Furthermore the role of ROS was assessed following delayed treatment with the ROS scavenger dimethylthiourea (DMTU) after brain ischemia. Results: ROS levels markedly increased at 1 hr after reperfusion and then gradually decreased as the post-reperfusion time interval increased. ROS levels reached their lowest point at 3 days after reperfusion before increasing and showing a second peak at 7 days after reperfusion. ROS levels negatively correlated with neurological function scores. Delayed DMTU treatment after stroke worsened neurological outcomes, decreased microvessel density and inhibited stress-activated protein kinase activation. Conclusion: ROS may play a biphasic role in cerebral ischemia. Namely, ROS may induce damage during the injury phase of brain ischemia and participate in improving neurological function during the recovery phase. [ABSTRACT FROM AUTHOR]