JavaScript notes

Functionality, scoping and asynchronous executions are three interesting features of JavaScript. This blog notes down some points:

  • Functionality of JavaScript
  • Scoping, this, and bind()
  • The closure pattern
  • Asynchronousity and callback hells

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Small Things in a Hackathon Website

Recently I have been using Flask to write this site. During the process I came across many small issues which took long time, and which should not, had I known about them in advance. Well, if you are also proceeding to writing your first 2000-line-scale Hackathon site, this blog might save you some time.
There are a few notes worth writing down.

  • Frontend: Use template or not
  • Backend: Deploying to AWS EC2 and RDS
  • Flask/Werkzeug: Scaling it up to enable multi-threadding
  • Flask: Submitting forms with data;
  • Practical problem: security
  • Practical problem: log-in control
  • Notes on redirecting
  • Apache: How to log and debug?
  • Discuss, Debug, and Deploy
  • Acknowledgements

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Java Review

When preparing for Java coding interview and implementing codes on Leetcode, I find it useful to have some of the most frequently used things written down in an “aid sheet”, just like this one.
This Java Review includes following contents:

  • I/O
  • Data Types
  • Regular Expressions
  • Methods and Classes
  • Running Java from command line
  • Some Classes and usages

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Artificial Neural Networks on Quadrotor Control

In summer of 2016 I had the privilege to work in Dynamic Systems Lab at UofT Institute of Aerospace Studies. I worked in a project group consisting of four undergraduate students which is supervised by two graduate students and Professor Angela Schoellig.
Throughout the summer we worked on finding possible applications of deep learning. There are a series of projects, which by the end of 16 weeks result in a paper submitted to IEEE International Conference of Robotics and Automation. (Updated 2017-01-22: The paper was accepted.)
This blog introduces the background, methodology, procedure, and experimental results of this project.

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How Does a Website Work (1) - Frontend, Backend

Websites are among the most popular things in our lives, but few passages have been talking about how they work as holistic parts. I have always wanted to see a passage demystifying websites, introducing different components of a website, and describing how they work together without losing the practicality aspects of tools.
This is a series of blogs, containing the following sections:

  • Components of a website
  • How frontend and backend communicate?
  • How does a server run?
  • How server and database cooperate?

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