Hello, this is my final examination narration，could you please do some advise for me about grammar, many thanks. How to handle AIS data. Good afternoon Prof. Xie, today I would like to introduce something about how to handle AIS data because this is my research direction. AIS(automatic identification system) is an equipment on vessel to transfer vessel name, speed, longitude, latitude and other message from vessel to shore equipment. Shore people can use AIS data to research how to avoid vessel accident or to analysis vessel transportation flow to improve vessel safety. AIS data have some errors, so we need to correct or delete AIS data before do AIS data research. In first, we need to delete AIS data which all content is same, this is same data but accepted by shore equipment for twice. In second, we need to delete speed over ground over 40 n mile data, if this is bulk vessel, tanker or contain vessel, these type vessel speed over ground should less 40 n mile, so if speed over ground over 40 n mile, this is error data. In third, for one trajectory if AIS point less 20 that mean this trajectory not a complete trajectory, that is a neglect trajectory so we need delete less 20 AIS point trajectory. After handle AIS data, we can use python to draw vessel trajectory map, look at PowerPoint, this is Ningbo Tiaozhoumen channel June,2021 trajectory map base on vessel’s speed, the point more blue, this vessel’s speed more less, the speed more yellow, this vessel’s speed more high. We can find all most points speed less 12 n mile because bulk vessel speed more less than contain vessel or other vessel meanwhile Tiaozhoumen channel is a narrow channel so bulk vessel sail with less speed to confirm vessel safety. Above all is my presentation, I introduce how to handle AIS data and how to draw AIS data trajectory map, meanwhile I display a result for Prof. review and do a introduction of this map, hope my presentation is clearly for you, many thanks.