CMPSC 431 and CS 446 fixed broken links

README.md

@@ -166,7 +166,7 @@ Courses
 
 ### Database Systems
 
-- [CMPSC 431W Database Management Systems, Fall 2015 - PSU](http://www.cse.psu.edu/~yul189/cmpsc431w/lectures.html)
+- [CMPSC 431W Database Management Systems, Fall 2015 - Penn State University](http://www.cse.psu.edu/~wul2/cmpsc431w/) [Lectures - YouTube](https://www.youtube.com/playlist?list=PLstRzn3gXZMdXqAiVJ1NN2CoyXHqma7pQ)
 - [CS121 - Introduction to Relational Database Systems, Fall 2016 - Caltech](http://users.cms.caltech.edu/~donnie/cs121/)
 - [CS 5530 - Database Systems, Spring 2016 - University of Utah](https://www.youtube.com/playlist?list=PLbuogVdPnkCrercQNP9tTsjjPdgRVYvC7)
 - [MOOC - Database Stanford Dbclass](https://www.youtube.com/playlist?list=PL6hGtHedy2Z4EkgY76QOcueU8lAC4o6c3)
@@ -274,7 +274,7 @@ Courses
 	- [10-601 - Introduction to Machine Learning (MS), CMU](http://www.cs.cmu.edu/~ninamf/courses/601sp15/lectures.shtml) ([YouTube](https://www.youtube.com/playlist?list=PLAJ0alZrN8rD63LD0FkzKFiFgkOmEtltQ))
 	- [10-701 - Introduction to Machine Learning (PhD) - Tom Mitchell, Spring 2011, CMU](http://www.cs.cmu.edu/~tom/10701_sp11/lectures.shtml) ([Fall 2014](https://www.youtube.com/playlist?list=PL7y-1rk2cCsDZCVz2xS7LrExqidHpJM3B)) ([Spring 2015 by Alex Smola](https://www.youtube.com/playlist?list=PLZSO_6-bSqHTTV7w9u7grTXBHMH-mw3qn))
 	- [Microsoft Research - Machine Learning Course](https://www.youtube.com/playlist?list=PL34iyE0uXtxo7vPXGFkmm6KbgZQwjf9Kf)
-	- [CS 446 - Machine Learning, Fall 2016, UIUC](http://l2r.cs.illinois.edu/~danr/Teaching/CS446-16/schedule.html)([Fall 2015 Lectures](https://www.youtube.com/playlist?list=PLQcasX5-oG91n10wPxeRh-45-8HATwc8W))
+	- [CS 446 - Machine Learning, Spring 2019, UIUC](https://courses.engr.illinois.edu/cs446/sp2019/AGS/_site/)([ Fall 2016 Lectures](https://www.youtube.com/playlist?list=PLQcasX5-oG91TgY6A_gz-IW7YSpwdnD2O))
 	- [undergraduate machine learning at UBC 2012, Nando de Freitas](https://www.youtube.com/playlist?list=PLE6Wd9FR--Ecf_5nCbnSQMHqORpiChfJf)
 	- [CS 229 - Machine Learning - Stanford University](https://see.stanford.edu/Course/CS229)
 	- [CS 189/289A Introduction to Machine Learning, Prof Jonathan Shewchuk - UCBerkeley](https://people.eecs.berkeley.edu/~jrs/189/)