I attended Cornell Summer Program after spring semester in 2017. During the program we were taught by Prof. Elaine Shi and Prof. David Gries, had social events with professors and PhDs in Cornell and had a lot of afterschool activities like Niagara Falls tour etc. I would like to write a brief summary here to be in memory of the unforgettable summer.

We spent most of the morning in Gates Hall when we were in Cornell University. Prof. Elaine gave us lectures about blockchain and introduced the safety concerns in detail. I hadn’t gone through knowledge about bitcoin, blockchain and distributed systems before, so I tried to search for introduction and papers about them to be quickly prepared with the class. In the lectures afterwards I tried my best to understand the algorithms and discussed with classmates after class to make them clear in time. In the project arranged by Prof. Elaine I helped the integrator team to write introduction of Stubborn Adversary Attack and Selfish Eclipse Attack in the project whitepaper.

Prof. David Gries taught us Programming Semantics and Programming Methodology. Before I took the course I had always written a loop body first and consider the loop bound afterwards. Bugs often appear in this way and it requires lots of time to debug and find the real loop bound. Prof. David tried to derivate loop invariant by strict math and logic in order to guarantee the correctness of the loop. Although it takes some time to derivate the loop invariant, programs developed in this way are strictly correct and save a great amount of time in debugging. Prof. Gries also paid a lot of attention to communication with us and was willing to walk around to make sure that everyone had fully understand what he had said. He corrected our assignments by himself as well and gave me some advice on my coding habits, which benefited me a great deal.

I had communicated with Prof. Knepper before I came to Cornell. After talking about his projects face to face I chose to join his blimp project and help to modify the firmware of Pixhawk which is the blimp’s controller. During this project I gained deeper knowledge about embedded systems with ARM chips and learned DIP controller in control theory. Apart from the project I also discussed campus life in Cornell with undergraduate teammates and had a good time talking about the difference between universities in China and the US. I met with Prof. Knepper several times as well to discuss not only the project but my future career planning. We talked about the difference between a PhD degree and a master degree and the reason and characteristics needed to pursue a PhD degree. Prof. Knepper was satisfied with my contribution during the summer and I presented him a traditional Chinese paper cut before I left Cornell to thank him for his instructions.

Time flied fast during the four weeks. I am grateful to the convenience from professors and staff of Cornell University and help given by Prof. Yu Yong, Teacher Wu Haiyan, Teacher Fan Wenfang and staff from Zhiyuan College contributing to this program. I may the program be better and better and juniors benefit more from the program.