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<?xml version="1.0" encoding="utf-8"?>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<HEAD>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<TITLE>2014/15 BSc Projects</TITLE>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<BASE HREF="http://www.inf.kcl.ac.uk/staff/urbanc/">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<script type="text/javascript" src="striper.js"></script>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<link rel="stylesheet" href="nominal.css">
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<script type="text/javascript" src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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</script>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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</HEAD>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<BODY TEXT="#000000"
Christian Urban <christian dot urban at kcl dot ac dot uk>
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BGCOLOR="#4169E1"
Christian Urban <christian dot urban at kcl dot ac dot uk>
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LINK="#0000EF"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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VLINK="#51188E"
Christian Urban <christian dot urban at kcl dot ac dot uk>
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ALINK="#FF0000"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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ONLOAD="striper('ul','striped','li','first,second')">
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parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<TABLE WIDTH="100%"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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BGCOLOR="#4169E1"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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BORDER="0"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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FRAME="border"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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CELLPADDING="10"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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CELLSPACING="2"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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RULES="all">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<TR>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<TD BGCOLOR="#FFFFFF"
Christian Urban <christian dot urban at kcl dot ac dot uk>
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WIDTH="75%"
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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VALIGN="TOP">
Christian Urban <christian dot urban at kcl dot ac dot uk>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<H2>2014/15 BSc Projects</H2>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<H4>Supervisor: Christian Urban</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<H4>Email: christian dot urban at kcl dot ac dot uk, Office: Strand Building S1.27</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<H4>If you are interested in a project, please send me an email and we can discuss details. Please include
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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a short description about your programming skills and Computer Science background in your first email.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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I will also need your King's username in order to book the project for you. Thanks.</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<H4>Note that besides being a lecturer at the theoretical end of Computer Science, I am also a passionate
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/Hacker_(programmer_subculture)">hacker</A> …
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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defined as “a person who enjoys exploring the details of programmable systems and
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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stretching their capabilities, as opposed to most users, who prefer to learn only the minimum
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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necessary.” I am always happy to supervise like-minded students.</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<ul class="striped">
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<li> <H4>[CU1] Regular Expression Matching and Derivatives</H4>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<B>Description:</b>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/Regular_expression">Regular expressions</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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are extremely useful for many text-processing tasks such as finding patterns in texts,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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lexing programs, syntax highlighting and so on. Given that regular expressions were
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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introduced in 1950 by <A HREF="http://en.wikipedia.org/wiki/Stephen_Cole_Kleene">Stephen Kleene</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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you might think regular expressions have since been studied and implemented to death. But you would definitely be
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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mistaken: in fact they are still an active research area. For example
312
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">this paper</A>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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about regular expression matching and derivatives was presented just last summer at the international
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
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FLOPS'14 conference. The task in this project is to implement their results.</p>
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>The background for this project is that some regular expressions are
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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“<A HREF="http://en.wikipedia.org/wiki/ReDoS#Examples">evil</A>”
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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and can “stab you in the back” according to
315
Christian Urban <christian dot urban at kcl dot ac dot uk>
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this <A HREF="http://peterscott.github.io/2013/01/17/regular-expressions-will-stab-you-in-the-back/">blog post</A>.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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For example, if you use in <A HREF="http://www.python.org">Python</A> or
323
Christian Urban <christian dot urban at kcl dot ac dot uk>
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in <A HREF="http://www.ruby-lang.org/en/">Ruby</A> (or also in a number of other mainstream programming languages according to this
313
Christian Urban <christian dot urban at kcl dot ac dot uk>
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+ − 67
<A HREF="http://www.computerbytesman.com/redos/">blog</A>) the
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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innocently looking regular expression <code>a?{28}a{28}</code> and match it, say, against the string
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<code>aaaaaaaaaaaaaaaaaaaaaaaaaaaa</code> (that is 28 <code>a</code>s), you will soon notice that your CPU usage goes to 100%. In fact,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Python and Ruby need approximately 30 seconds of hard work for matching this string. You can try it for yourself:
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://www.dcs.kcl.ac.uk/staff/urbanc/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/re.py">re.py</A> (Python version) and
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 72
<A HREF="http://www.dcs.kcl.ac.uk/staff/urbanc/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/re.rb">re.rb</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(Ruby version). You can imagine an attacker
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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mounting a nice <A HREF="http://en.wikipedia.org/wiki/Denial-of-service_attack">DoS attack</A> against
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 75
your program if it contains such an “evil” regular expression. Actually
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 76
<A HREF="http://www.scala-lang.org/">Scala</A> (and also Java) are almost immune from such
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 77
attacks as they can deal with strings of up to 4,300 <code>a</code>s in less than a second. But if you scale
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 78
the regular expression and string further to, say, 4,600 <code>a</code>s, then you get a <code>StackOverflowError</code>
314
Christian Urban <christian dot urban at kcl dot ac dot uk>
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potentially crashing your program. Moreover (beside the "minor" problem of being painfully slow) according to this
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">report</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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nearly all POSIX regular expression matchers are actually buggy.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 85
On a rainy afternoon, I implemented
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 86
<A HREF="http://www.dcs.kcl.ac.uk/staff/urbanc/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/re3.scala">this</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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regular expression matcher in Scala. It is not as fast as the official one in Scala, but
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 88
it can match up to 11,000 <code>a</code>s in less than 5 seconds without raising any exception
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(remember Python and Ruby both need nearly 30 seconds to process 28(!) <code>a</code>s, and Scala's
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 90
official matcher maxes out at 4,600 <code>a</code>s). My matcher is approximately
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 91
85 lines of code and based on the concept of
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://lambda-the-ultimate.org/node/2293">derivatives of regular expressions</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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These derivatives were introduced in 1964 by <A HREF="http://en.wikipedia.org/wiki/Janusz_Brzozowski_(computer_scientist)">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 94
Janusz Brzozowski</A>, but according to this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://www.cl.cam.ac.uk/~so294/documents/jfp09.pdf">paper</A> had been lost in the “sands of time”.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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The advantage of derivatives is that they side-step completely the usual
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://hackingoff.com/compilers/regular-expression-to-nfa-dfa">translations</A> of regular expressions
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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into NFAs or DFAs, which can introduce the exponential behaviour exhibited by the regular
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 99
expression matchers in Python and Ruby.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 100
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 103
Now the authors from the
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">FLOPS'14-paper</A> mentioned
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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above claim they are even faster than me and can deal with even more features of regular expressions
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(for example subexpression matching, which my rainy-afternoon matcher cannot). I am sure they thought
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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about the problem much longer than a single afternoon. The task
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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in this project is to find out how good they actually are by implementing the results from their paper.
316
Christian Urban <christian dot urban at kcl dot ac dot uk>
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Their approach is based on the concept of derivatives.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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I used them once myself in a <A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/Publications/rexp.pdf">paper</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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in order to prove the <A HREF="http://en.wikipedia.org/wiki/Myhill–Nerode_theorem">Myhill-Nerode theorem</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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So I know they are worth their money. Still, it would be interesting to actually compare their results
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 113
with my simple rainy-afternoon matcher and potentially “blow away” the regular expression matchers
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
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+ − 114
in Python and Ruby (and possibly in Scala too). The application would be to implement a fast lexer for
Christian Urban <christian dot urban at kcl dot ac dot uk>
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+ − 115
programming languages.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<B>Literature:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 120
The place to start with this project is obviously this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/ppdp12-part-deriv-sub-match.pdf">paper</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Traditional methods for regular expression matching are explained
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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in the Wikipedia articles
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/DFA_minimization">here</A> and
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/Powerset_construction">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 126
The authoritative <A HREF="http://infolab.stanford.edu/~ullman/ialc.html">book</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 127
on automata and regular expressions is by John Hopcroft and Jeffrey Ullmann (available in the library).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 128
There is also an online course about this topic by Ullman at
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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<A HREF="https://www.coursera.org/course/automata">Coursera</A>, though IMHO not
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 130
done with love.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 131
Finally, there are millions of other pointers about regular expression
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 132
matching on the Web. I found the chapter on Lexing in this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://www.diku.dk/~torbenm/Basics/">online book</A> very helpful.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 134
Test cases for “<A HREF="http://en.wikipedia.org/wiki/ReDoS#Examples">evil</A>”
316
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
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+ − 135
regular expressions can be obtained from <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">here</A>.
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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+ − 136
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 138
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 139
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 140
<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 141
This is a project for a student with an interest in theory and some
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 142
reasonable programming skills. The project can be easily implemented
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 143
in functional languages like
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 144
<A HREF="http://www.scala-lang.org/">Scala</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 145
F#,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 146
<A HREF="http://en.wikipedia.org/wiki/Standard_ML">ML</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 147
<A HREF="http://haskell.org/haskellwiki/Haskell">Haskell</A>, etc. Python and other non-functional languages
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 148
can be also used, but seem much less convenient.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 150
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<li> <H4>[CU2] A Compiler for a small Programming Language</H4>
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 154
<b>Description:</b>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 155
Compilers translate high-level programs that humans can read and write into
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 156
efficient machine code that can be run on a CPU or virtual machine.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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A compiler for a simple functional language generating X86 code is described
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="https://github.com/chameco/Shade">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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I recently implemented a very simple compiler for an even simpler functional
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 160
programming language following this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://www.cs.princeton.edu/~dpw/papers/tal-toplas.pdf">paper</A>
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(also described <A HREF="http://www.cs.princeton.edu/~dpw/papers/tal-tr.pdf">here</A>).
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My code, written in <A HREF="http://www.scala-lang.org/">Scala</A>, of this compiler is
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<A HREF="http://www.dcs.kcl.ac.uk/staff/urbanc/compiler.scala">here</A>.
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The compiler can deal with simple programs involving natural numbers, such
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as Fibonacci numbers or factorial (but it can be easily extended - that is not the point).
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</p>
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<p>
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While the hard work has been done (understanding the two papers above),
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my compiler only produces some idealised machine code. For example I
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assume there are infinitely many registers. The goal of this
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project is to generate machine code that is more realistic and can
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run on a CPU, like X86, or run on a virtual machine, say the JVM.
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This gives probably a speedup of thousand times in comparison to
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my naive machine code and virtual machine. The project
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requires to dig into the literature about real CPUs and generating
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real machine code.
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</p>
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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An alternative is to not generate machine code, but build a compiler that compiles to
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<A HREF="http://www.w3schools.com/js/">JavaScript</A>. This is the language that is supported by most
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browsers and therefore is a favourite
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vehicle for Web-programming. Some call it <B>the</B> scripting language of the Web.
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Unfortunately, JavaScript is also probably one of the worst
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languages to program in (being designed and released in a hurry). <B>But</B> it can be used as a convenient target
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for translating programs from other languages. In particular there are two
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very optimised subsets of JavaScript that can be used for this purpose:
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one is <A HREF="http://asmjs.org">asm.js</A> and the other is
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<A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>.
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There is a <A HREF="http://kripken.github.io/emscripten-site/docs/getting_started/Tutorial.html">tutorial</A> for emscripten
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and an impressive <A HREF="http://www.unrealengine.com/html5/">demo</A> which runs the
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<A HREF="http://en.wikipedia.org/wiki/Unreal_Engine">Unreal Engine 3</A>
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in a browser with spectacular speed. This was achieved by compiling the
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C-code of the Unreal Engine to the LLVM intermediate language and then translating the LLVM
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code to JavaScript.
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</p>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<B>Literature:</B>
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There is a lot of literature about compilers
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(for example <A HREF="http://www.cs.princeton.edu/~appel/papers/cwc.html">this book</A> -
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I can lend you my copy for the duration of the project, or this
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<A HREF="http://www.diku.dk/~torbenm/Basics/">online book</A>). A very good overview article
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about implementing compilers by
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<A HREF="http://tratt.net/laurie/">Laurie Tratt</A> is
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<A HREF="http://tratt.net/laurie/tech_articles/articles/how_difficult_is_it_to_write_a_compiler">here</A>.
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An online book about the Art of Assembly Language is
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<A HREF="http://flint.cs.yale.edu/cs422/doc/art-of-asm/pdf/">here</A>.
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An introduction into x86 machine code is <A HREF="http://ianseyler.github.com/easy_x86-64/">here</A>.
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Intel's official manual for the x86 instruction is
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<A HREF="http://download.intel.com/design/intarch/manuals/24319101.pdf">here</A>.
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A simple assembler for the JVM is described <A HREF="http://jasmin.sourceforge.net">here</A>.
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An interesting twist of this project is to not generate code for a CPU, but
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for the intermediate language of the <A HREF="http://llvm.org">LLVM</A> compiler
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(also described <A HREF="http://llvm.org/docs/LangRef.html">here</A>). If you want to see
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what machine code looks like you can compile your C-program using gcc -S.
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</p>
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<p>
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If JavaScript is chosen as a target instead, then there are plenty of <A HREF="http://www.w3schools.com/js/">tutorials</A> on the Web.
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<A HREF="http://jsbooks.revolunet.com">Here</A> is a list of free books on JavaScript.
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A project from which you can draw inspiration is this
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<A HREF="http://jlongster.com/2012/01/04/outlet-my-lisp-to-javascript-experiment.html">List-to-JavaScript</A>
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translator. <A HREF="https://bitbucket.org/ktg/parenjs/overview">Here</A> is another such project.
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And <A HREF="https://github.com/viclib/liscript">another</A> in less than 100 lines of code.
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<A HREF="http://en.wikipedia.org/wiki/CoffeeScript">Coffeescript</A> is a similar project
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except that it is already quite <A HREF="http://coffeescript.org">mature</A>. And finally not to
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forget <A HREF="http://www.typescriptlang.org">TypeScript</A> developed by Microsoft. The main
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difference between these projects and this one is that they translate into relatively high-level
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JavaScript code; none of them use the much lower levels <A HREF="http://asmjs.org">asm.js</A> and
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<A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>.
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<B>Skills:</B>
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This is a project for a student with a deep interest in programming languages and
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compilers. Since my compiler is implemented in <A HREF="http://www.scala-lang.org/">Scala</A>,
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it would make sense to continue this project in this language. I can be
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of help with questions and books about <A HREF="http://www.scala-lang.org/">Scala</A>.
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But if Scala is a problem, my code can also be translated quickly into any other functional
Christian Urban <christian dot urban at kcl dot ac dot uk>
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language.
Christian Urban <christian dot urban at kcl dot ac dot uk>
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<p>
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<B>PS:</B> Compiler projects, like this one or [CU8], consistently received high marks in the past.
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I suprvised four so far and none of them received a mark below 70% - one even was awarded a prize.
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</p>
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<li> <H4>[CU3] Slide-Making in the Web-Age</H4>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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The standard technology for writing scientific papers in Computer Science is to use
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<A HREF="http://en.wikipedia.org/wiki/LaTeX">LaTeX</A>, a document preparation
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system originally implemented by <A HREF="http://en.wikipedia.org/wiki/Donald_Knuth">Donald Knuth</A>
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and <A HREF="http://en.wikipedia.org/wiki/Leslie_Lamport">Leslie Lamport</A>.
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LaTeX produces very pleasantly looking documents, can deal nicely with mathematical
Christian Urban <christian dot urban at kcl dot ac dot uk>
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formulas and is very flexible. If you are interested, <A HREF="http://openwetware.org/wiki/Word_vs._LaTeX">here</A>
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is a side-by-side comparison between Word and LaTeX (which LaTeX “wins” with 18 out of 21 points).
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Computer scientists not only use LaTeX for documents,
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but also for slides (really, nobody who wants to be cool uses Keynote or Powerpoint).
Christian Urban <christian dot urban at kcl dot ac dot uk>
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Although used widely, LaTeX seems nowadays a bit dated for producing
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slides. Unlike documents, which are typically “static” and published in a book or journal,
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slides often contain changing contents that might first only be partially visible and
Christian Urban <christian dot urban at kcl dot ac dot uk>
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only later be revealed as the “story” of a talk or lecture demands.
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Also slides often contain animated algorithms where each state in the
Christian Urban <christian dot urban at kcl dot ac dot uk>
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calculation is best explained by highlighting the changing data.
Christian Urban <christian dot urban at kcl dot ac dot uk>
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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It seems HTML and JavaScript are much better suited for generating
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such animated slides. This <A HREF="http://www.impressivewebs.com/html-slidedeck-toolkits/">page</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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links to 22 slide-generating programs using this combination of technologies.
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However, the problem with all of these project is that they depend heavily on the users being
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able to write JavaScript, CCS or HTML...not something one would like to depend on given that
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“normal” users likely only have a LaTeX background. The aim of this project is to invent a
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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very simple language that is inspired by LaTeX and then generate from code written in this language
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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slides that can be displayed in a web-browser.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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This sounds complicated, but there is already some help available:
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://www.mathjax.org">Mathjax</A> is a JavaScript library that can
Christian Urban <christian dot urban at kcl dot ac dot uk>
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be used to display mathematical text, for example
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<blockquote>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<p>When \(a \ne 0\), there are two solutions to \(ax^2 + bx + c = 0\) and they are
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\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\).</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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</blockquote>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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317
Christian Urban <christian dot urban at kcl dot ac dot uk>
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by writing code in the familiar LaTeX-way. This can be reused.
Christian Urban <christian dot urban at kcl dot ac dot uk>
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Another such library is <A HREF="http://khan.github.io/KaTeX/">KaTeX</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
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There are also plenty of JavaScript
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libraries for graphical animations (for example
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://raphaeljs.com">Raphael</A>,
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<A HREF="http://svgjs.com">SVG.JS</A>,
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<A HREF="http://bonsaijs.org">Bonsaijs</A>,
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<A HREF="http://jsxgraph.uni-bayreuth.de/wp/">JSXGraph</A>). The inspiration for how the user should be able to write
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slides could come from the LaTeX packages <A HREF="http://en.wikipedia.org/wiki/Beamer_(LaTeX)">Beamer</A>
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and <A HREF="http://en.wikipedia.org/wiki/PGF/TikZ">PGF/TikZ</A>.
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parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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This is a project requires good knowledge of JavaScript. You need to be able to
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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parse a language and translate it to a suitable part of JavaScript using
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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appropriate libraries. Tutorials for JavaScript are <A HREF="http://www.w3schools.com/js/">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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A parser generator for JavaScript is <A HREF="http://pegjs.majda.cz">here</A>. There are probably also
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others. If you want to avoid JavaScript there are a number of alternatives: for example the
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<A HREF="http://elm-lang.org">Elm</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
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language has been especially designed for implementing easily interactive animations, which would be
316
Christian Urban <christian dot urban at kcl dot ac dot uk>
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very convenient for this project.
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parents:
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</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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311
Christian Urban <christian dot urban at kcl dot ac dot uk>
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<li> <H4>[CU4] An Online Student Voting System</H4>
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<B>Description:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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One of the more annoying aspects of giving a lecture is to ask a question
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parents:
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to the students and no matter how easy the question is to not
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Christian Urban <christian dot urban at kcl dot ac dot uk>
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receive any answer. The online course system
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<A HREF="http://www.udacity.com">Udacity</A>, in contrast, made an art out of
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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asking questions during lectures (see for example the
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 325
<A HREF="http://www.udacity.com/overview/Course/cs253/CourseRev/apr2012">Web Application Engineering</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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course CS253).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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The lecturer there gives multiple-choice questions as part of the lecture and the students need to
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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click on the appropriate answer. This works very well in the online world.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 329
For “real-world” lectures, the department has some
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/Audience_response">clickers</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(these are little devices which form a part of an audience response systems). However,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 332
they are a logistic nightmare for the lecturer: they need to be distributed
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 333
during the lecture and collected at the end. Nowadays, where students
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 334
come with their own laptop or smartphone to lectures, this can
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 335
be improved.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 336
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 337
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 338
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 339
The task of this project is to implement an online student
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 340
polling system. The lecturer should be able to prepare
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 341
questions beforehand (encoded as some web-form) and be able to
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 342
show them during the lecture. The students
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 343
can give their answers by clicking on the corresponding webpage.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 344
The lecturer can then collect the responses online and evaluate them
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 345
immediately. Such a system is sometimes called
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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<A HREF="http://en.wikipedia.org/wiki/Audience_response#Smartphone_.2F_HTTP_voting">HTML voting</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 347
There are a number of commercial
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 348
solutions for this problem, but they are not easy to use (in addition
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 349
to being ridiculously expensive). A good student can easily improve upon
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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+ − 350
what they provide.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 351
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 352
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 353
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 354
The problem of student polling is not as hard as
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 355
<A HREF="http://en.wikipedia.org/wiki/Electronic_voting">electronic voting</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
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+ − 356
which essentially is still an unsolved problem in Computer Science. The
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 357
students only need to be prevented from answering question more than once thus skewing
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 358
any statistics. Unlike electronic voting, no audit trail needs to be kept
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 359
for student polling. Restricting the number of answers can probably be solved
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 360
by setting appropriate cookies on the students
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 361
computers or smart phones.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 362
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 363
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 364
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 365
<B>Literature:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 366
The project requires fluency in a web-programming language (for example
316
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 367
<A HREF="http://en.wikipedia.org/wiki/JavaScript">JavaScript</A>,
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 368
<A HREF="http://en.wikipedia.org/wiki/Go_(programming_language)">Go</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 369
<A HREF="http://www.scala-lang.org/">Scala</A>). However JavaScript with
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 370
the <A HREF="http://nodejs.org">Node.js</A> extension seems to be best suited for the job.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 371
<A HREF="http://www.nodebeginner.org">Here</A> is a tutorial on Node.js for beginners.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 372
For web-programming the
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 373
<A HREF="http://www.udacity.com/overview/Course/cs253/CourseRev/apr2012">Web Application Engineering</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 374
course at <A HREF="http://www.udacity.com">Udacity</A> is a good starting point
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 375
to be aware of the issues involved. This course uses <A HREF="http://www.python.org">Python</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 376
To evaluate the answers from the students, Google's
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 377
<A HREF="https://developers.google.com/chart/image/docs/making_charts">Chart Tools</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 378
might be useful, which is also described in this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 379
<A HREF="http://www.youtube.com/watch?v=NZtgT4jgnE8">youtube</A> video.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 380
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 381
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 382
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 383
<B>Skills:</B>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 384
In order to provide convenience for the lecturer, this project needs very good web-programming skills. A
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 385
<A HREF="http://en.wikipedia.org/wiki/Hacker_(programmer_subculture)">hacker mentality</A>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 386
(see above) is probably also very beneficial: web-programming is an area that only emerged recently and
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 387
many tools still lack maturity. You probably have to experiment a lot with several different
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 388
languages and tools.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 389
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 390
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 391
<li> <H4>[CU5] Raspberry Pi's and Arduinos</H4>
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 392
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 393
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 394
<B>Description:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 395
This project is for true hackers! <A HREF="http://en.wikipedia.org/wiki/Raspberry_Pi">Raspberry Pi's</A>
329
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 396
are small Linux computers the size of a credit-card and only cost £34 (see picture on the left below). They were introduced
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 397
in 2012 and people went crazy...well some of them. There is a
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 398
<A HREF="https://plus.google.com/communities/113390432655174294208?hl=en">Google+</A> community about Raspberry Pi's that has more
316
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 399
than 172k of followers. It is hard to keep up with what people do with these small computers. The possibilities
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 400
seem to be limitless. The main resource for Raspberry Pi's is <A HREF="http://www.raspberrypi.org">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 401
There are <A HREF="http://www.themagpi.com">magazines</A> dedicated to them and tons of
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 402
<A HREF="http://www.raspberrypi.org/phpBB3/viewforum.php?f=39">books</A> (not to mention
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 403
floods of <A HREF="https://www.google.co.uk/search?q=raspberry+pi">online</A> material).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 404
Google just released a
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 405
<A HREF="http://googlecreativelab.github.io/coder/">framework</A>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 406
for web-programming on Raspberry Pi's truning them into webservers.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 407
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 408
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 409
<p>
329
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 410
<A HREF="http://en.wikipedia.org/wiki/Arduino">Arduinos</A> are slightly older (from 2005) but still very cool (see picture on the right below). They
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 411
are small single-board micro-controllers that can talk to various external gadgets (sensors, motors, etc). Since Arduinos
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 412
are open-software and open-hardware there are many clones and add-on boards. Like for the Raspberry Pi, there
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 413
is a lot of material <A HREF="https://www.google.co.uk/search?q=arduino">available</A> about Arduinos.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 414
The main reference is <A HREF="http://www.arduino.cc">here</A>. Like the Raspberry Pi's, the good thing about
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 415
Arduinos is that they can be powered with simple AA-batteries.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 416
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 417
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 418
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 419
I have two such Raspberry Pi's including wifi-connectors and two <A HREF="http://www.raspberrypi.org/camera">cameras<A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 420
I also have two <A HREF="http://www.freaklabs.org/index.php/Blog/Store/Introducing-the-Freakduino-Chibi-An-Arduino-based-Board-For-Wireless-Sensor-Networking.html">Freakduino Boards</A> that are Arduinos extended with wireless communication. I can lend them to responsible
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 421
students for one or two projects. However, the aim is to first come up with an idea for a project. Popular projects are
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 422
automated temperature sensors, network servers, robots, web-cams (<A HREF="http://www.secretbatcave.co.uk/electronics/shard-rain-cam/">here</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 423
is a <A HREF="http://www.raspberrypi.org/archives/3547">web-cam</A> directed at the Shard that can
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 424
<A HREF="http://www.secretbatcave.co.uk/software/shard-rain-cam-quantifying-cloudy/">tell</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 425
you whether it is raining or cloudy). There are plenty more ideas listed
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 426
<A HREF="http://www.raspberrypi.org/phpBB3/viewforum.php?f=15">here</A> for Raspberry Pi's and
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 427
<A HREF="http://playground.arduino.cc/projects/ideas">here</A> for Arduinos.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 428
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 429
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 430
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 431
There are essentially two kinds of projects: One is purely software-based. Software projects for Raspberry Pi's are often
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 432
written in <A HREF="http://www.python.org">Python</A>, but since these are Linux-capable computers any other
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 433
language would do as well. You can also write your own operating system as done
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 434
<A HREF="http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/">here</A>. For example the students
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 435
<A HREF="http://www.recantha.co.uk/blog/?p=4918">here</A> developed their own bare-metal OS and then implemented
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 436
a chess-program on top of it (have a look at their very impressive
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 437
<A HREF="http://www.youtube.com/watch?v=-03bouPsfEQ&feature=player_embedded">youtube</A> video).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 438
The other kind of project is a combination of hardware and software; usually attaching some sensors
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 439
or motors to the Raspberry Pi or Arduino. This might require some soldering or what is called
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 440
a <A HREF="http://en.wikipedia.org/wiki/Breadboard">bread-board</A>. But be careful before choosing a project
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 441
involving new hardware: these devices
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 442
can be destroyed (if “Vin connected to GND” or “drawing more than 30mA from a GPIO”
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 443
does not make sense to you, you should probably stay away from such a project).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 444
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 445
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 446
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 447
<center>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 448
<img style="-webkit-user-select: none; cursor: -webkit-zoom-in;
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 449
"src="http://upload.wikimedia.org/wikipedia/commons/3/3d/RaspberryPi.jpg" width="313" height="209">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 450
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 451
<img style="-webkit-user-select: none; cursor: -webkit-zoom-in;
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 452
"src="http://upload.wikimedia.org/wikipedia/commons/3/38/Arduino_Uno_-_R3.jpg" width="240" height="209">
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 453
</center>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 454
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 455
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 456
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 457
<B>Skills:</B>
322
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 458
Well, you must be a hacker; happy to make things. Your desk might look like on the photo on the left.
324
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 459
The right photo shows an earlier student project which connects wirelessly a wearable Arduino (packaged
326
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 460
in a "self-3d-printed" watch) to a Raspberry Pi seen in the background. The Arduino takes meaurements of
330
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 461
heart rate and body temperature; the Raspberry Pi collects this data and makes it accessible via a simple
321
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 462
web-service.
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 463
<center>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 464
<img style="-webkit-user-select: none; cursor: -webkit-zoom-in;
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 465
"src="http://www.inf.kcl.ac.uk/staff/urbanc/rpi-photo.jpg" width="209" height="313">
318
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 466
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 467
<img style="-webkit-user-select: none; cursor: -webkit-zoom-in;
320
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 468
"src="http://www.inf.kcl.ac.uk/staff/urbanc/rpi-watch.jpg" width="450" height="254">
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 469
</center>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 470
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 471
331
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 472
<li> <H4>[CU6] Generating Testcases from a Specification</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 473
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 474
<li> <H4>[CU7] GPRS + GPS for Arduinos</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 475
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 476
<li> <H4>[CU8] Language Translator into JavaScript</H4>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 477
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 478
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 479
<b>Description:</b>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 480
<A HREF="http://www.w3schools.com/js/">JavaScript</A> is a language that is supported by most
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 481
browsers and therefore is a favourite
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 482
vehicle for Web-programming. Some call it <B>the</B> scripting language of the Web.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 483
Unfortunately, JavaScript is probably one of the worst
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 484
languages to program in (being designed and released in a hurry). <B>But</B> it can be used as a convenient target
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 485
for translating programs from other languages. In particular there are two
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 486
very optimised subsets of JavaScript that can be used for this purpose:
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 487
one is <A HREF="http://asmjs.org">asm.js</A> and the other is
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 488
<A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 489
There is a <A HREF="https://github.com/kripken/emscripten/wiki/Tutorial">tutorial</A> for emscripten
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 490
and an impressive <A HREF="http://www.unrealengine.com/html5/">demo</A> which runs the
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 491
<A HREF="http://en.wikipedia.org/wiki/Unreal_Engine">Unreal Engine 3</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 492
in a browser with spectacular speed. This was achieved by compiling the
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 493
C-code of the Unreal Engine to the LLVM intermediate language and then translating the LLVM
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 494
code to JavaScript.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 495
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 496
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 497
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 498
<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 499
This project is about exploring these two subsets of JavaScript and implement a translator
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 500
of a small language into them. This is similar to the project [CU2] above and requires
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 501
similar skills. In addition it would be good to have already some familiarity with JavaScript.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 502
There are plenty of <A HREF="http://www.w3schools.com/js/">tutorials</A> on the Web.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 503
<A HREF="http://jsbooks.revolunet.com">Here</A> is a list of free books on JavaScript.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 504
This is a project for a student who wants to get more familiar with JavaScript and Web-programming.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 505
A project from which you can draw inspiration is this
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 506
<A HREF="http://jlongster.com/2012/01/04/outlet-my-lisp-to-javascript-experiment.html">List-to-JavaScript</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 507
translator. <A HREF="https://bitbucket.org/ktg/parenjs/overview">Here</A> is another such project.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 508
And <A HREF="https://github.com/viclib/liscript">another</A> in less than 100 lines of code.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 509
<A HREF="http://en.wikipedia.org/wiki/CoffeeScript">Coffeescript</A> is a similar project
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 510
except that it is already quite <A HREF="http://coffeescript.org">mature</A>. And finally not to
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 511
forget <A HREF="http://www.typescriptlang.org">TypeScript</A> developed by Microsoft. The main
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 512
difference between these projects and this one is that they translate into relatively high-level
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 513
JavaScript code; none of them use the much lower levels <A HREF="http://asmjs.org">asm.js</A> and
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 514
<A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 515
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 516
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 517
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 518
331
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 519
<li> <H4>[CU9] An Infrastructure for Displaying and Animating Code in a Web-Browser</H4>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 520
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 521
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 522
<B>Description:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 523
The project aim is to implement an infrastructure for displaying and
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 524
animating code in a web-browser. The infrastructure should be agnostic
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 525
with respect to the programming language, but should be configurable.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 526
I envisage something smaller than the projects
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 527
<A HREF="http://www.pythontutor.com">here</A> (for Python),
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 528
<A HREF="http://ideone.com">here</A> (for Java),
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 529
<A HREF="http://codepad.org">here</A> (for multiple languages),
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 530
<A HREF="http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro">here</A> (for HTML)
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 531
<A HREF="http://repl.it/languages/JavaScript">here</A> (for JavaScript),
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 532
and <A HREF="http://www.scala-tour.com/#/welcome">here</A> (for Scala).
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 533
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 534
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 535
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 536
The tasks in this project are being able (1) to lex and parse languages and (2) to write an interpreter.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 537
The goal is to implement this as much as possible in a language-agnostic fashion.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 538
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 539
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 540
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 541
<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 542
Good skill in lexing and language parsing, as well as being fluent with web programming (for
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 543
example JavaScript).
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 544
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 545
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 546
331
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 547
<li> <H4>[CU10] Implementation of a Distributed Clock-Synchronisation Algorithm developed at NASA</H4>
311
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 548
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 549
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 550
<B>Description:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 551
There are many algorithms for synchronising clocks. This
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 552
<A HREF="http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120000054_2011025573.pdf">paper</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 553
describes a new algorithm for clocks that communicate by exchanging
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 554
messages and thereby reach a state in which (within some bound) all clocks are synchronised.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 555
A slightly longer and more detailed paper about the algorithm is
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 556
<A HREF="http://hdl.handle.net/2060/20110020812">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 557
The point of this project is to implement this algorithm and simulate networks of clocks.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 558
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 559
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 560
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 561
<B>Literature:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 562
There is a wide range of literature on clock synchronisation algorithms.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 563
Some pointers are given in this
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 564
<A HREF="http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120000054_2011025573.pdf">paper</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 565
which describes the algorithm to be implemented in this project. Pointers
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 566
are given also <A HREF="http://en.wikipedia.org/wiki/Clock_synchronization">here</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 567
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 568
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 569
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 570
<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 571
In order to implement a simulation of a network of clocks, you need to tackle
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 572
concurrency. You can do this for example in the programming language
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 573
<A HREF="http://www.scala-lang.org/">Scala</A> with the help of the
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 574
<A HREF="http://akka.io">Akka</a> library. This library enables you to send messages
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 575
between different <I>actors</I>. <A HREF="http://www.scala-lang.org/node/242">Here</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 576
are some examples that explain how to implement exchanging messages between actors.
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 577
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 578
331
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 579
<li> <H4>[CU11] Proving the Correctness of Programs</H4>
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 580
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 581
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 582
I am one of the main developers of the interactive theorem prover
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 583
<A HREF="http://isabelle.in.tum.de">Isabelle</A>. This theorem prover
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 584
has been used to establish the correctness of some quite large
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 585
programs (for example an <A HREF="http://ertos.nicta.com.au/research/l4.verified/">operating system</A>).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 586
Together with colleagues from Nanjing, I used this theorem prover to establish the correctness of a
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 587
scheduling algorithm, called
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 588
<A HREF="http://en.wikipedia.org/wiki/Priority_inheritance">Priority Inheritance</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 589
for real time operating systems. This scheduling algorithm is part of the operating
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 590
system that drives, for example, the
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 591
<A HREF="http://en.wikipedia.org/wiki/Mars_Exploration_Rover">Mars rovers</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 592
Actually, the very first Mars rover mission in 1997 did not have this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 593
algorithm switched on and it almost caused a catastrophic mission failure (see
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 594
this youtube video <A HREF="http://www.youtube.com/watch?v=lyx7kARrGeM">here</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 595
for an explanation what happened).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 596
We were able to prove the correctness of this algorithm, but were also able to
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 597
establish the correctness of some optimisations in this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 598
<A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/Publications/pip.pdf">paper</A>.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 599
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 600
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 601
<p>On a much smaller scale, there are a few small programs and underlying algorithms where it
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 602
is not really understood whether they always compute a correct result (for example the
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 603
regular expression matcher by Sulzmann and Lu in project [CU1]). The aim of this
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 604
project is to completely specify an algorithm in Isabelle and then prove it correct (that is,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 605
it always computes the correct result).
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 606
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 607
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 608
<p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 609
<B>Skills:</B>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 610
This project is for a very good student with a knack for theoretical things and formal reasoning.
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 611
</p>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 612
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 613
<li> <H4>Earlier Projects</H4>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 614
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 615
I am also open to project suggestions from you. You might find some inspiration from my earlier projects:
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 616
<A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/bsc-projects-12.html">BSc 2012/13</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 617
<A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/msc-projects-12.html">MSc 2012/13</A>,
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 618
<A HREF="http://www.inf.kcl.ac.uk/staff/urbanc/bsc-projects-13.html">BSc 2013/14</A>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 619
</ul>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 620
</TD>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 621
</TR>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 622
</TABLE>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 623
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 624
<P>
331
Christian Urban <christian dot urban at kcl dot ac dot uk>
diff
changeset
+ − 625
<!-- hhmts start --> Last modified: Wed Oct 1 12:02:06 BST 2014 <!-- hhmts end -->
297
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 626
<a href="http://validator.w3.org/check/referer">[Validate this page.]</a>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 627
</BODY>
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
diff
changeset
+ − 628
</HTML>