At present, governments around the world and the organization are demonstrating how to deploy LEO communication constellations, such as Starlink, space-based information network and other mega constellations. With the satellite increasing quantity，it greatly increases the risk of satellite in orbit collision. In case of satellite collision early warning, the satellite depends on ground system early warning information, and then guides the satellite to avoid maneuver, the whole chain takes a long time and involves the coordination of multiple departments, multiple personnel and different links. The management cost is very high and the efficiency is low, which cannot meet the needs of orbit collision management of mega constellations .Autonomous avoiding of satellites on orbit is an inevitable trend. In this paper, we devise a scheme for satellite autonomic avoiding on low orbit mega constellations. By analyzing the orbit debris environment of spacecraft, its collision early warning theory is established, the strategies and methods for orbit avoidance are formulated, spacecraft warning software is based on continually update cata--log database，what is also used for Orbit early warning and avoidance. It will provide technical support for the healthy on orbit operation of mega constellation in the future.

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AimsThis study aims to describe the clinical characteristics, laboratory data and complications of hospitalized COVID-19 patients with type 2 diabetes mellitus (T2DM) since epidemic prevention and control optimization was adjusted in December 2022 in China.MethodsThis retrospective multicenter study included 298 patients with confirmed type 2 diabetes mellitus with or without COVID-19. We collected data from the first wave of the pandemic in The Fifth Affiliated Hospital of Guangzhou Medical University, Loudi Central Hospital and The First People’s Hospital of Xiangtan from December 1, 2022 to February 1, 2023. We extracted baseline data, clinical symptoms, acute complications, laboratory findings, treatment and outcome data of each patient from electronic medical records.ResultsFor among 298 hospitalized patients with type 2 diabetes, 136 (45.6%) were COVID-19 uninfected, and 162 (54.4%) were COVID-19 infected. We found that the incidence of cough, fatigue, fever, muscle soreness, sore throat, shortness of breath, hyposmia, hypogeusia and polyphagia (all p<0.01) were significantly higher in the exposure group. They showed higher levels of ketone (p=0.04), creatinine (p<0.01), blood potassium (p=0.01) and more diabetic ketoacidosis (p<0.01). Patients with COVID-19 less use of metformin (p<0.01), thiazolidinediones (p<0.01) and SGLT2 (p<0.01) compared with patients without COVID-19.ConclusionCOVID-19 patients with diabetes showed more severe respiratory and constitutional symptoms and an increased proportion of hyposmia and hypogeusia. Moreover, COVID-19 patients with diabetes have a higher incidence of acute complications, are more prone to worsening renal function, and are more cautious about the use of antidiabetic drugs.

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