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|  |     32 | 
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|  |     33 | <H2>2017/18 MSc Projects</H2>
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|  |     34 | <H4>Supervisor: Christian Urban</H4> 
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|  |     35 | <H4>Email: christian dot urban at kcl dot ac dot uk,  Office: Bush House N7.07</H4>
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|  |     36 | <H4>If you are interested in a project, please send me an email and we can discuss details. Please include
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|  |     37 | a short description about your programming skills and Computer Science background in your first email. 
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|  |     38 | Thanks.</H4> 
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|  |     39 | 
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|  |     40 | <H4>Note that besides being a lecturer at the theoretical end of Computer Science, I am also a passionate
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|  |     41 |     <A HREF="http://en.wikipedia.org/wiki/Hacker_(programmer_subculture)">hacker</A> …
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|  |     42 |     defined as “a person who enjoys exploring the details of programmable systems and 
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|  |     43 |     stretching their capabilities, as opposed to most users, who prefer to learn only the minimum 
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|  |     44 |     necessary.” I am always happy to supervise like-minded students.
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|  |     45 | </H4>
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|  |     46 | 
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|  |     47 | <H4>In 2013/14, I was nominated by the students
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|  |     48 |     for the best BSc project supervisor and best MSc project supervisor awards in the NMS
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|  |     49 |     faculty. Somehow I won both. In 2014/15 I was nominated again for the best MSc
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|  |     50 |     project supervisor, but did not win it. ;o)
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|  |     51 | </H4>  
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|  |     52 | 
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|  |     53 | <ul class="striped">
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|  |     54 | <li> <H4>[CU1] Regular Expressions, Lexing and Derivatives</H4>
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|  |     55 | 
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|  |     56 |   <p>
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|  |     57 |   <B>Description:</b>  
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|  |     58 |   <A HREF="http://en.wikipedia.org/wiki/Regular_expression">Regular expressions</A> 
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|  |     59 |   are extremely useful for many text-processing tasks, such as finding patterns in hostile network traffic,
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|  |     60 |   lexing programs, syntax highlighting and so on. Given that regular expressions were
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|  |     61 |   introduced in 1950 by <A HREF="http://en.wikipedia.org/wiki/Stephen_Cole_Kleene">Stephen Kleene</A>,
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|  |     62 |   you might think regular expressions have since been studied and implemented to death. But you would definitely be
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|  |     63 |   mistaken: in fact they are still an active research area. On the top of my head, I can give
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|  |     64 |   you at least ten research papers that appeared in the last few years.
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|  |     65 |   For example
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|  |     66 |   <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">this paper</A> 
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|  |     67 |   about regular expression matching and derivatives was presented in 2014 at the international 
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| 522 |     68 |   FLOPS conference. Another <A HREF="https://nms.kcl.ac.uk/christian.urban/Publications/posix.pdf">paper</A> by my PhD student and me was presented in 2016
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| 520 |     69 |   at the international ITP conference.
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|  |     70 |   The task in this project is to implement these results and use them for lexing.</p>
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|  |     71 | 
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|  |     72 |   <p>The background for this project is that some regular expressions are 
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|  |     73 |   “<A HREF="http://en.wikipedia.org/wiki/ReDoS#Examples">evil</A>”
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|  |     74 |   and can “stab you in the back” according to
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|  |     75 |   this <A HREF="http://peterscott.github.io/2013/01/17/regular-expressions-will-stab-you-in-the-back/">blog post</A>.
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|  |     76 |   For example, if you use in <A HREF="http://www.python.org">Python</A> or 
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|  |     77 |   in <A HREF="http://www.ruby-lang.org/en/">Ruby</A> (or also in a number of other mainstream programming languages) the 
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|  |     78 |   innocently looking regular expression <code>a?{28}a{28}</code> and match it, say, against the string 
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|  |     79 |   <code>aaaaaaaaaaaaaaaaaaaaaaaaaaaa</code> (that is 28 <code>a</code>s), you will soon notice that your CPU usage goes to 100%. In fact,
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|  |     80 |   Python and Ruby need approximately 30 seconds of hard work for matching this string. You can try it for yourself:
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|  |     81 |   <A HREF="http://talisker.inf.kcl.ac.uk/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/catastrophic.py">catastrophic.py</A> (Python version) and 
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|  |     82 |   <A HREF="http://talisker.inf.kcl.ac.uk/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/catastrophic.rb">catastrophic.rb</A> 
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|  |     83 |   (Ruby version). Here is a similar problem in Java: <A HREF="http://talisker.inf.kcl.ac.uk/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/catastrophic.rb">catastrophic.java</A> 
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|  |     84 |   </p> 
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|  |     85 | 
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|  |     86 |   <p>
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|  |     87 |   You can imagine an attacker
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|  |     88 |   mounting a nice <A HREF="http://en.wikipedia.org/wiki/Denial-of-service_attack">DoS attack</A> against 
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|  |     89 |   your program if it contains such an “evil” regular expression. But it can also happen by accident:
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|  |     90 |   on 20 July 2016 the website <A HREF="http://stackstatus.net/post/147710624694/outage-postmortem-july-20-2016">Stack Exchange</A>
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|  |     91 |   was knocked offline because of an evil regular expression. One of their engineers talks about this in this
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|  |     92 |   <A HREF="https://vimeo.com/112065252">video</A>. A similar problem needed to be fixed in the
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|  |     93 |   <A HREF="http://davidvgalbraith.com/how-i-fixed-atom/">Atom</A> editor.
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|  |     94 |   A few implementations of regular expression matchers are almost immune from such problems.
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|  |     95 |   For example, <A HREF="http://www.scala-lang.org/">Scala</A> can deal with strings of up to 4,300 <code>a</code>s in less than a second. But if you scale
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|  |     96 |   the regular expression and string further to, say, 4,600 <code>a</code>s, then you get a <code>StackOverflowError</code> 
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|  |     97 |   potentially crashing your program. Moreover (beside the "minor" problem of being painfully slow) according to this
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|  |     98 |   <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">report</A>
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|  |     99 |   nearly all regular expression matchers using the POSIX rules are actually buggy.
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|  |    100 |   </p>
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|  |    101 | 
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|  |    102 |   <p>
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|  |    103 |   On a rainy afternoon, I implemented 
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|  |    104 |   <A HREF="http://talisker.inf.kcl.ac.uk/cgi-bin/repos.cgi/afl-material/raw-file/tip/progs/re3.scala">this</A> 
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|  |    105 |   regular expression matcher in Scala. It is not as fast as the official one in Scala, but
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|  |    106 |   it can match up to 11,000 <code>a</code>s in less than 5 seconds  without raising any exception
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|  |    107 |   (remember Python and Ruby both need nearly 30 seconds to process 28(!) <code>a</code>s, and Scala's
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|  |    108 |   official matcher maxes out at 4,600 <code>a</code>s). My matcher is approximately
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|  |    109 |   85 lines of code and based on the concept of 
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|  |    110 |   <A HREF="http://lambda-the-ultimate.org/node/2293">derivatives of regular expressions</A>.
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|  |    111 |   These derivatives were introduced in 1964 by <A HREF="http://en.wikipedia.org/wiki/Janusz_Brzozowski_(computer_scientist)">
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|  |    112 |   Janusz Brzozowski</A>, but according to this
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|  |    113 |   <A HREF="https://www.cs.kent.ac.uk/people/staff/sao/documents/jfp09.pdf">paper</A> had been lost in the “sands of time”.
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|  |    114 |   The advantage of derivatives is that they side-step completely the usual 
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|  |    115 |   <A HREF="http://hackingoff.com/compilers/regular-expression-to-nfa-dfa">translations</A> of regular expressions
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|  |    116 |   into NFAs or DFAs, which can introduce the exponential behaviour exhibited by the regular
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|  |    117 |   expression matchers in Python, Java and Ruby.
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|  |    118 |   </p>
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|  |    119 | 
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|  |    120 |   <p>
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|  |    121 |   Now the authors from the 
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|  |    122 |   <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">FLOPS'14-paper</A> mentioned 
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|  |    123 |   above claim they are even faster than me and can deal with even more features of regular expressions
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|  |    124 |   (for example subexpression matching, which my rainy-afternoon matcher cannot). I am sure they thought
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|  |    125 |   about the problem much longer than a single afternoon. The task 
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|  |    126 |   in this project is to find out how good they actually are by implementing the results from their paper. 
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|  |    127 |   Their approach to regular expression matching is also based on the concept of derivatives.
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|  |    128 |   I used derivatives very successfully once for something completely different in a
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| 522 |    129 |   <A HREF="https://nms.kcl.ac.uk/christian.urban/Publications/rexp.pdf">paper</A> 
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| 520 |    130 |   about the <A HREF="http://en.wikipedia.org/wiki/Myhill–Nerode_theorem">Myhill-Nerode theorem</A>.
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|  |    131 |   So I know they are worth their money. Still, it would be interesting to actually compare their results
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|  |    132 |   with my simple rainy-afternoon matcher and potentially “blow away” the regular expression matchers 
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|  |    133 |   in Python, Ruby and Java (and possibly in Scala too). The application would be to implement a fast lexer for
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|  |    134 |   programming languages, or improve the network traffic analysers in the tools <A HREF="https://www.snort.org">Snort</A> and
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|  |    135 |   <A HREF="https://www.bro.org">Bro</A>.
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|  |    136 |   </p>
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|  |    137 | 
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|  |    138 |   <p>
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|  |    139 |   <B>Literature:</B> 
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|  |    140 |   The place to start with this project is obviously this
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|  |    141 |   <A HREF="http://www.home.hs-karlsruhe.de/~suma0002/publications/regex-parsing-derivatives.pdf">paper</A>
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| 522 |    142 |   and this <A HREF="https://nms.kcl.ac.uk/christian.urban/Publications/posix.pdf">one</A>.
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| 520 |    143 |   Traditional methods for regular expression matching are explained
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|  |    144 |   in the Wikipedia articles 
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|  |    145 |   <A HREF="http://en.wikipedia.org/wiki/DFA_minimization">here</A> and 
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|  |    146 |   <A HREF="http://en.wikipedia.org/wiki/Powerset_construction">here</A>.
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|  |    147 |   The authoritative <A HREF="http://infolab.stanford.edu/~ullman/ialc.html">book</A>
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|  |    148 |   on automata and regular expressions is by John Hopcroft and Jeffrey Ullmann (available in the library). 
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|  |    149 |   There is also an online course about this topic by Ullman at 
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|  |    150 |   <A HREF="https://www.coursera.org/course/automata">Coursera</A>, though IMHO not 
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|  |    151 |   done with love. 
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|  |    152 |   There are millions of other pointers about regular expression
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|  |    153 |   matching on the Web. I found the chapter on Lexing in this
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|  |    154 |   <A HREF="http://www.diku.dk/~torbenm/Basics/">online book</A> very helpful. Finally, it will
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|  |    155 |   be of great help for this project to take part in my Compiler and Formal Language module (6CCS3CFL).
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|  |    156 |   Test cases for “<A HREF="http://en.wikipedia.org/wiki/ReDoS#Examples">evil</A>”
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|  |    157 |   regular expressions can be obtained from <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">here</A>.
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|  |    158 |   </p>
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|  |    159 | 
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|  |    160 |   <p>
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|  |    161 |   <B>Skills:</B> 
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|  |    162 |   This is a project for a student with an interest in theory and with
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|  |    163 |   good programming skills. The project can be easily implemented
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|  |    164 |   in functional languages like
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|  |    165 |   <A HREF="http://www.scala-lang.org/">Scala</A>,
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|  |    166 |   <A HREF="http://fsharp.org">F#</A>, 
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|  |    167 |   <A HREF="http://en.wikipedia.org/wiki/Standard_ML">ML</A>,  
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|  |    168 |   <A HREF="http://haskell.org/haskellwiki/Haskell">Haskell</A>, etc. Python and other non-functional languages
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|  |    169 |   can be also used, but seem much less convenient. If you do attend my Compilers and Formal Languages
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|  |    170 |   module, that would obviously give you a head-start with this project.
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|  |    171 |   </p>
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|  |    172 |   
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|  |    173 | <li> <H4>[CU2] A Compiler for a small Programming Language</H4>
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|  |    174 | 
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|  |    175 |   <p>
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|  |    176 |   <b>Description:</b> 
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|  |    177 |   Compilers translate high-level programs that humans can read and write into
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|  |    178 |   efficient machine code that can be run on a CPU or virtual machine.
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|  |    179 |   A compiler for a simple functional language generating X86 code is described
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|  |    180 |   <A HREF="https://libraries.io/github/chameco/Shade">here</A>.
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|  |    181 |   I recently implemented a very simple compiler for an even simpler functional
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|  |    182 |   programming language following this 
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|  |    183 |   <A HREF="https://www.cs.princeton.edu/~dpw/papers/tal-toplas.pdf">paper</A> 
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|  |    184 |   (also described <A HREF="https://www.cs.princeton.edu/~dpw/papers/tal-tr.pdf">here</A>).
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|  |    185 |   My code, written in <A HREF="http://www.scala-lang.org/">Scala</A>, of this compiler is 
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|  |    186 |   <A HREF="https://nms.kcl.ac.uk/christian.urban/compiler.scala">here</A>.
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|  |    187 |   The compiler can deal with simple programs involving natural numbers, such
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|  |    188 |   as Fibonacci numbers or factorial (but it can be easily extended - that is not the point).
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|  |    189 |   </p>
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|  |    190 | 
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|  |    191 |   <p>
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|  |    192 |   While the hard work has been done (understanding the two papers above),
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|  |    193 |   my compiler only produces some idealised machine code. For example I
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|  |    194 |   assume there are infinitely many registers. The goal of this
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|  |    195 |   project is to generate machine code that is more realistic and can
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|  |    196 |   run on a CPU, like X86, or run on a virtual machine, say the JVM. 
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|  |    197 |   This gives probably a speedup of thousand times in comparison to
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|  |    198 |   my naive machine code and virtual machine. The project
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|  |    199 |   requires to dig into the literature about real CPUs and generating 
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|  |    200 |   real machine code. 
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|  |    201 |   </p>
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|  |    202 |   <p>
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|  |    203 |   An alternative is to not generate machine code, but build a compiler that compiles to
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|  |    204 |   <A HREF="http://www.w3schools.com/js/">JavaScript</A>. This is the language that is supported by most
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|  |    205 |   browsers and therefore is a favourite
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|  |    206 |   vehicle for Web-programming. Some call it <B>the</B> scripting language of the Web.
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|  |    207 |   Unfortunately, JavaScript is also probably one of the worst
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|  |    208 |   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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|  |    209 |   for translating programs from other languages. In particular there are two
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|  |    210 |   very optimised subsets of JavaScript that can be used for this purpose:
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|  |    211 |   one is <A HREF="http://asmjs.org">asm.js</A> and the other is
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|  |    212 |   <A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>. Since
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|  |    213 |   last year there is even the official <A HREF="http://webassembly.org">Webassembly</A>
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|  |    214 |   There is a <A HREF="http://kripken.github.io/emscripten-site/docs/getting_started/Tutorial.html">tutorial</A> for emscripten
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|  |    215 |   and an impressive <A HREF="https://youtu.be/c2uNDlP4RiE">demo</A> which runs the
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|  |    216 |   <A HREF="http://en.wikipedia.org/wiki/Unreal_Engine">Unreal Engine 3</A>
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|  |    217 |   in a browser with spectacular speed. This was achieved by compiling the
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|  |    218 |   C-code of the Unreal Engine to the LLVM intermediate language and then translating the LLVM
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|  |    219 |   code to JavaScript.
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|  |    220 |   </p>
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|  |    221 | 
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|  |    222 |   <p>
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|  |    223 |   <B>Literature:</B>
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|  |    224 |   There is a lot of literature about compilers 
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|  |    225 |   (for example <A HREF="http://www.cs.princeton.edu/~appel/papers/cwc.html">this book</A> -
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|  |    226 |   I can lend you my copy for the duration of the project, or this
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|  |    227 |   <A HREF="http://www.diku.dk/~torbenm/Basics/">online book</A>). A very good overview article
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|  |    228 |   about implementing compilers by 
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|  |    229 |   <A HREF="http://tratt.net/laurie/">Laurie Tratt</A> is 
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|  |    230 |   <A HREF="http://tratt.net/laurie/tech_articles/articles/how_difficult_is_it_to_write_a_compiler">here</A>.
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|  |    231 |   An online book about the Art of Assembly Language is
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|  |    232 |   <A HREF="http://flint.cs.yale.edu/cs422/doc/art-of-asm/pdf/">here</A>.
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|  |    233 |   An introduction into x86 machine code is <A HREF="http://ianseyler.github.com/easy_x86-64/">here</A>.
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|  |    234 |   Intel's official manual for the x86 instruction is 
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|  |    235 |   <A HREF="http://download.intel.com/design/intarch/manuals/24319101.pdf">here</A>. 
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|  |    236 |   Two assemblers for the JVM are described <A HREF="http://jasmin.sourceforge.net">here</A>
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|  |    237 |   and <A HREF="https://github.com/Storyyeller/Krakatau">here</A>.
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|  |    238 |   An interesting twist of this project is to not generate code for a CPU, but
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|  |    239 |   for the intermediate language of the <A HREF="http://llvm.org">LLVM</A> compiler
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|  |    240 |   (also described <A HREF="http://llvm.org/docs/LangRef.html">here</A>). If you want to see
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|  |    241 |   what machine code looks like you can compile your C-program using gcc -S.
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|  |    242 |   </p>
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|  |    243 |   <p>
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|  |    244 |   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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|  |    245 |   <A HREF="http://jsbooks.revolunet.com">Here</A> is a list of free books on JavaScript.
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|  |    246 |   A project from which you can draw inspiration is this
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|  |    247 |   <A HREF="http://jlongster.com/Outlet--My-Lisp-to-Javascript-Experiment">Lisp-to-JavaScript</A>
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|  |    248 |   translator. <A HREF="https://bitbucket.org/ktg/parenjs/overview">Here</A> is another such project.
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|  |    249 |   And <A HREF="https://github.com/viclib/liscript">another</A> in less than 100 lines of code.
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|  |    250 |   <A HREF="http://en.wikipedia.org/wiki/CoffeeScript">Coffeescript</A> is a similar project
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|  |    251 |   except that it is already quite <A HREF="http://coffeescript.org">mature</A>. And finally not to
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|  |    252 |   forget <A HREF="http://www.typescriptlang.org">TypeScript</A> developed by Microsoft. The main
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|  |    253 |   difference between these projects and this one is that they translate into relatively high-level
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|  |    254 |   JavaScript code; none of them use the much lower levels <A HREF="http://asmjs.org">asm.js</A> and 
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|  |    255 |   <A HREF="https://github.com/kripken/emscripten/wiki">emscripten</A>.
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|  |    256 |   </p>
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|  |    257 |   <p>
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|  |    258 |   <B>Skills:</B> 
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|  |    259 |   This is a project for a student with a deep interest in programming languages and
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|  |    260 |   compilers. Since my compiler is implemented in <A HREF="http://www.scala-lang.org/">Scala</A>,
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|  |    261 |   it would make sense to continue this project in this language. I can be
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|  |    262 |   of help with questions and books about <A HREF="http://www.scala-lang.org/">Scala</A>.
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|  |    263 |   But if Scala is a problem, my code can also be translated quickly into any other functional
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|  |    264 |   language. Again,  it will be of great help for this project to take part in
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|  |    265 |   my Compiler and Formal Language module (6CCS3CFL).
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|  |    266 |   </p>
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|  |    267 | 
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|  |    268 |   <p>
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|  |    269 |   <B>PS:</B> Compiler projects consistently received high marks in the past.
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|  |    270 |   I have supervised eight so far and most of them received a mark above 70% - one even was awarded a prize.
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|  |    271 |   </p>
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|  |    272 | 
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|  |    273 | <li> <H4>[CU3] Slide-Making in the Web-Age</H4>
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|  |    274 | 
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|  |    275 |   <p>
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|  |    276 |   The standard technology for writing scientific papers in Computer Science  is to use
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|  |    277 |   <A HREF="http://en.wikipedia.org/wiki/LaTeX">LaTeX</A>, a document preparation
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|  |    278 |   system originally implemented by <A HREF="http://en.wikipedia.org/wiki/Donald_Knuth">Donald Knuth</A>
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|  |    279 |   and <A HREF="http://en.wikipedia.org/wiki/Leslie_Lamport">Leslie Lamport</A>.
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|  |    280 |   LaTeX produces very pleasantly looking documents, can deal nicely with mathematical
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|  |    281 |   formulas and is very flexible. If you are interested, <A HREF="http://openwetware.org/wiki/Word_vs._LaTeX">here</A>
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|  |    282 |   is a side-by-side comparison between Word and LaTeX (which LaTeX “wins” with 18 out of 21 points).
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|  |    283 |   Computer scientists not only use LaTeX for documents,
 | 
|  |    284 |   but also for slides (really, nobody who wants to be cool uses Keynote or Powerpoint).
 | 
|  |    285 |   </p>
 | 
|  |    286 | 
 | 
|  |    287 |   <p>
 | 
|  |    288 |   Although used widely, LaTeX seems nowadays a bit dated for producing
 | 
|  |    289 |   slides. Unlike documents, which are typically “static” and published in a book or journal,
 | 
|  |    290 |   slides often contain changing contents that might first only be partially visible and
 | 
|  |    291 |   only later be revealed as the “story” of a talk or lecture demands.
 | 
|  |    292 |   Also slides often contain animated algorithms where each state in the
 | 
|  |    293 |   calculation is best explained by highlighting the changing data.
 | 
|  |    294 |   </p>
 | 
|  |    295 | 
 | 
|  |    296 |   <p>
 | 
|  |    297 |   It seems HTML and JavaScript are much better suited for generating
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|  |    298 |   such animated slides. This <A HREF="http://www.impressivewebs.com/html-slidedeck-toolkits/">page</A>
 | 
|  |    299 |   links to slide-generating programs using this combination of technologies. 
 | 
|  |    300 |   However, the problem with all of these project is that they depend heavily on the users being
 | 
|  |    301 |   able to write JavaScript, CCS or HTML...not something one would like to depend on given that
 | 
|  |    302 |   “normal” users likely only have a LaTeX background. The aim of this project is to invent a
 | 
|  |    303 |   very simple language that is inspired by LaTeX and then generate from code written in this language
 | 
|  |    304 |   slides that can be displayed in a web-browser. An example would be the
 | 
|  |    305 |   <A HREF="https://www.madoko.net">Madoko</A> project.
 | 
|  |    306 |   </p>
 | 
|  |    307 | 
 | 
|  |    308 |  <p>
 | 
|  |    309 |  This sounds complicated, but there is already some help available:
 | 
|  |    310 |  <A HREF="http://www.mathjax.org">Mathjax</A> is a JavaScript library that can
 | 
|  |    311 |  be used to display mathematical text, for example</p>
 | 
|  |    312 | 
 | 
|  |    313 |  <blockquote>
 | 
|  |    314 |  <p>When \(a \ne 0\), there are two solutions to \(ax^2 + bx + c = 0\) and they are
 | 
|  |    315 |  \(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\).</p>
 | 
|  |    316 |  </blockquote>
 | 
|  |    317 | 
 | 
|  |    318 |  <p> 
 | 
|  |    319 |  by writing code in the familiar LaTeX-way. This can be reused.
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|  |    320 |  Another such library is <A HREF="http://khan.github.io/KaTeX/">KaTeX</A>.
 | 
|  |    321 |  There are also plenty of JavaScript
 | 
|  |    322 |  libraries for graphical animations (for example
 | 
|  |    323 |  <A HREF="http://raphaeljs.com">Raphael</A>,
 | 
|  |    324 |  <A HREF="http://svgjs.com">SVG.JS</A>,
 | 
|  |    325 |  <A HREF="http://bonsaijs.org">Bonsaijs</A>,
 | 
|  |    326 |  <A HREF="http://jsxgraph.uni-bayreuth.de/wp/">JSXGraph</A>). The inspiration for how the user should be able to write
 | 
|  |    327 |  slides could come from the LaTeX packages <A HREF="http://en.wikipedia.org/wiki/Beamer_(LaTeX)">Beamer</A>
 | 
|  |    328 |  and <A HREF="http://en.wikipedia.org/wiki/PGF/TikZ">PGF/TikZ</A>. A slide-making project from which
 | 
|  |    329 |  inspiration can be drawn is <A HREF="http://maciejczyzewski.me/hyhyhy/">hyhyhy</A>.
 | 
|  |    330 |  </p>
 | 
|  |    331 | 
 | 
|  |    332 |   <p>
 | 
|  |    333 |   <B>Skills:</B> 
 | 
|  |    334 |   This is a project that requires good knowledge of JavaScript. You need to be able to
 | 
|  |    335 |   parse a language and translate it to a suitable part of JavaScript using
 | 
|  |    336 |   appropriate libraries. Tutorials for JavaScript are <A HREF="http://www.w3schools.com/js/">here</A>.
 | 
|  |    337 |   A parser generator for JavaScript is <A HREF="http://pegjs.majda.cz">here</A>. There are probably also
 | 
|  |    338 |   others. If you want to avoid JavaScript there are a number of alternatives: for example the
 | 
|  |    339 |   <A HREF="http://elm-lang.org">Elm</A>
 | 
|  |    340 |   language has been especially designed for implementing interactive animations, which would be
 | 
|  |    341 |   very convenient for this project. A nice slide making project done by a previous student is 
 | 
|  |    342 |   <A HREF="http://www.markslides.org">MarkSlides</A> by Oleksandr Cherednychenko. 
 | 
|  |    343 |   </p>
 | 
|  |    344 | 
 | 
|  |    345 | <li> <H4>[CU4] Raspberry Pi's and Arduinos</H4>
 | 
|  |    346 | 
 | 
|  |    347 |   <p>
 | 
|  |    348 |   <B>Description:</B>
 | 
|  |    349 |   This project is for true hackers! <A HREF="http://en.wikipedia.org/wiki/Raspberry_Pi">Raspberry Pi's</A>
 | 
|  |    350 |   are small Linux computers the size of a credit-card and only cost £26, the
 | 
|  |    351 |   simplest version even costs only £5 (see pictures on the left below). They were introduced
 | 
|  |    352 |   in 2012 and people went crazy...well some of them. There is a
 | 
|  |    353 |   <A HREF="https://plus.google.com/communities/113390432655174294208?hl=en">Google+</A>
 | 
|  |    354 |   community about Raspberry Pi's that has more
 | 
|  |    355 |   than 197k of followers. It is hard to keep up with what people do with these small computers. The possibilities
 | 
|  |    356 |   seem to be limitless. The main resource for Raspberry Pi's is <A HREF="http://www.raspberrypi.org">here</A>.
 | 
|  |    357 |   There are <A HREF="https://www.raspberrypi.org/magpi/">magazines</A> dedicated to them and tons of
 | 
|  |    358 |   <A HREF="http://www.raspberrypi.org/phpBB3/viewforum.php?f=39">books</A> (not to mention
 | 
|  |    359 |   floods of <A HREF="https://www.google.co.uk/search?q=raspberry+pi">online</A> material,
 | 
|  |    360 |   such as the <A HREF="https://www.raspberrypi.org/magpi-issues/Projects_Book_v1.pdf">RPi projects book</A>).
 | 
|  |    361 |   Google just released a
 | 
|  |    362 |   <A HREF="http://googlecreativelab.github.io/coder/">framework</A>
 | 
|  |    363 |   for web-programming on Raspberry Pi's turning them into webservers.
 | 
|  |    364 |   In my home one Raspberry Pi has the very important task of automatically filtering out
 | 
|  |    365 |   nearly all advertisments using the 
 | 
|  |    366 |   <A HREF="https://github.com/pi-hole/pi-hole">Pi-Hole</A> software
 | 
|  |    367 |   (you cannot imagine what difference this does to your web experience...you just sit back and read what
 | 
|  |    368 |   is important).
 | 
|  |    369 |   </p>
 | 
|  |    370 | 
 | 
|  |    371 |   <p>
 | 
|  |    372 |   <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
 | 
|  |    373 |   are small single-board micro-controllers that can talk to various external gadgets (sensors, motors, etc). Since Arduinos
 | 
|  |    374 |   are open-software and open-hardware there are many clones and add-on boards. Like for the Raspberry Pi, there
 | 
|  |    375 |   is a lot of material <A HREF="https://www.google.co.uk/search?q=arduino">available</A> about Arduinos.
 | 
|  |    376 |   The main reference is <A HREF="http://www.arduino.cc">here</A>. Like the Raspberry Pi's, the good thing about
 | 
|  |    377 |   Arduinos is that they can be powered with simple AA-batteries.
 | 
|  |    378 |   </p>
 | 
|  |    379 | 
 | 
|  |    380 |   <p>
 | 
|  |    381 |   I have several Raspberry Pi's including wifi-connectors and two <A HREF="http://www.raspberrypi.org/camera">cameras</A>.
 | 
|  |    382 |   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
 | 
|  |    383 |   students for one or two projects. However, the aim is to first come up with an idea for a project. Popular projects are
 | 
|  |    384 |   automated temperature sensors, network servers, robots, web-cams (<A HREF="http://www.secretbatcave.co.uk/electronics/shard-rain-cam/">here</A>
 | 
|  |    385 |   is a <A HREF="http://www.raspberrypi.org/archives/3547">web-cam</A> directed at the Shard that can
 | 
|  |    386 |   <A HREF="http://www.secretbatcave.co.uk/software/shard-rain-cam-quantifying-cloudy/">tell</A>
 | 
|  |    387 |   you whether it is raining or cloudy). There are plenty more ideas listed
 | 
|  |    388 |   <A HREF="http://www.raspberrypi.org/phpBB3/viewforum.php?f=15">here</A> for Raspberry Pi's and
 | 
|  |    389 |   <A HREF="http://playground.arduino.cc/projects/ideas">here</A> for Arduinos.
 | 
|  |    390 |   </p>
 | 
|  |    391 | 
 | 
|  |    392 |   <p>
 | 
|  |    393 |   There are essentially two kinds of projects: One is purely software-based. Software projects for Raspberry Pi's are often
 | 
|  |    394 |   written in <A HREF="http://www.python.org">Python</A>, but since these are Linux-capable computers any other
 | 
|  |    395 |   language would do as well. You can also write your own operating system as done
 | 
|  |    396 |   <A HREF="http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/">here</A>. For example the students
 | 
|  |    397 |   <A HREF="http://www.recantha.co.uk/blog/?p=4918">here</A> developed their own bare-metal OS and then implemented
 | 
|  |    398 |   a chess-program on top of it (have a look at their very impressive
 | 
|  |    399 |   <A HREF="http://www.youtube.com/watch?v=-03bouPsfEQ&feature=player_embedded">youtube</A> video).
 | 
|  |    400 |   The other kind of project is a combination of hardware and software; usually attaching some sensors
 | 
|  |    401 |   or motors to the Raspberry Pi or Arduino. This might require some soldering or what is called
 | 
|  |    402 |   a <A HREF="http://en.wikipedia.org/wiki/Breadboard">bread-board</A>. But be careful before choosing a project
 | 
|  |    403 |   involving new hardware: these devices
 | 
|  |    404 |   can be destroyed (if “Vin connected to GND” or “drawing more than 30mA from a GPIO”
 | 
|  |    405 |   does not make sense to you, you should probably stay away from such a project). 
 | 
|  |    406 |   </p>
 | 
|  |    407 | 
 | 
|  |    408 |   <center>
 | 
|  |    409 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
|  |    410 |          src="http://upload.wikimedia.org/wikipedia/commons/3/3d/RaspberryPi.jpg"
 | 
|  |    411 |          alt="Raspberry Pi"
 | 
|  |    412 |          width="313" height="209">
 | 
|  |    413 | 
 | 
|  |    414 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
|  |    415 |          src="https://upload.wikimedia.org/wikipedia/commons/7/7e/Raspberry-Pi-Zero-FL.jpg"
 | 
|  |    416 |          alt="Raspberry Pi Zero"
 | 
|  |    417 |          width="313" height="209">  
 | 
|  |    418 | 
 | 
|  |    419 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
|  |    420 |          src="http://upload.wikimedia.org/wikipedia/commons/3/38/Arduino_Uno_-_R3.jpg"
 | 
|  |    421 |          alt="Arduino"
 | 
|  |    422 |          width="240" height="209">
 | 
|  |    423 |   </center>
 | 
|  |    424 |   
 | 
|  |    425 | 
 | 
|  |    426 |   <p>
 | 
|  |    427 |   <B>Skills:</B> 
 | 
|  |    428 |   Well, you must be a hacker; happy to make things. Your desk might look like the photo below on the left.
 | 
|  |    429 |   The photo below on the middle shows an earlier student project which connects wirelessly a wearable Arduino (packaged
 | 
|  |    430 |   in a "self-3d-printed" watch) to a Raspberry Pi seen in the background. The Arduino in the foreground takes
 | 
|  |    431 |   measurements of 
 | 
|  |    432 |   heart rate and body temperature; the Raspberry Pi collects this data and makes it accessible via a simple
 | 
|  |    433 |   web-service. The picture on the right is another project that implements an airmouse using an Arduino.
 | 
|  |    434 | 
 | 
|  |    435 |   <center>
 | 
|  |    436 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
| 522 |    437 |          src="https://nms.kcl.ac.uk/christian.urban/rpi-photo.jpg"
 | 
| 520 |    438 |          alt="Raspberry Pi"
 | 
|  |    439 |          width="209" height="313">
 | 
|  |    440 | 
 | 
|  |    441 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
| 522 |    442 |          src="https://nms.kcl.ac.uk/christian.urban/rpi-watch.jpg"
 | 
| 520 |    443 |          alt="Raspberry Pi"
 | 
|  |    444 |          width="450" height="254">
 | 
|  |    445 | 
 | 
|  |    446 |     <img style="-webkit-user-select: none; cursor: -webkit-zoom-in;"
 | 
| 522 |    447 |          src="https://nms.kcl.ac.uk/christian.urban/rpi-airmouse.jpg"
 | 
| 520 |    448 |          alt="Raspberry Pi"
 | 
|  |    449 |          width="250" height="254">  
 | 
|  |    450 |   </center>
 | 
|  |    451 |  
 | 
|  |    452 | 
 | 
|  |    453 | <li> <H4>[CU5] An Infrastructure for Displaying and Animating Code in a Web-Browser</H4>
 | 
|  |    454 |   
 | 
|  |    455 | <p>
 | 
|  |    456 |   <B>Description:</B>
 | 
|  |    457 |   The project aim is to implement an infrastructure for displaying and
 | 
|  |    458 |   animating code in a web-browser. The infrastructure should be agnostic
 | 
|  |    459 |   with respect to the programming language, but should be configurable.
 | 
|  |    460 |   I envisage something smaller than the projects 
 | 
|  |    461 |   <A HREF="http://www.pythontutor.com">here</A> (for Python),
 | 
|  |    462 |   <A HREF="http://ideone.com">here</A> (for Java),
 | 
|  |    463 |   <A HREF="http://codepad.org">here</A> (for multiple languages),
 | 
|  |    464 |   <A HREF="http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro">here</A> (for HTML)
 | 
|  |    465 |   <A HREF="http://repl.it/languages/JavaScript">here</A> (for JavaScript),
 | 
|  |    466 |   and <A HREF="http://www.scala-tour.com/#/welcome">here</A> (for Scala).
 | 
|  |    467 |   </p>
 | 
|  |    468 | 
 | 
|  |    469 |   <p>
 | 
|  |    470 |   The tasks in this project are being able (1) to lex and parse languages and (2) to write an interpreter.
 | 
|  |    471 |   The goal is to implement this as much as possible in a language-agnostic fashion.
 | 
|  |    472 |   </p>
 | 
|  |    473 | 
 | 
|  |    474 |   <p>
 | 
|  |    475 |   <B>Skills:</B> 
 | 
|  |    476 |   Good skills in lexing and language parsing, as well as being fluent with web programming (for
 | 
|  |    477 |   example JavaScript).
 | 
|  |    478 |   </p>
 | 
|  |    479 | 
 | 
|  |    480 | 
 | 
|  |    481 | <li> <H4>[CU6] Proving the Correctness of Programs</H4>
 | 
|  |    482 | 
 | 
|  |    483 |  <p>
 | 
|  |    484 |  I am one of the main developers of the interactive theorem prover
 | 
|  |    485 |  <A HREF="http://isabelle.in.tum.de">Isabelle</A>. This theorem prover
 | 
|  |    486 |  has been used to establish the correctness of some quite large
 | 
|  |    487 |  programs (for example an <A HREF="http://ertos.nicta.com.au/research/l4.verified/">operating system</A>).
 | 
|  |    488 |  Together with colleagues from Nanjing, I used this theorem prover to establish the correctness of a
 | 
|  |    489 |  scheduling algorithm, called
 | 
|  |    490 |  <A HREF="http://en.wikipedia.org/wiki/Priority_inheritance">Priority Inheritance</A>,
 | 
|  |    491 |  for real-time operating systems. This scheduling algorithm is part of the operating
 | 
|  |    492 |  system that drives, for example, the 
 | 
|  |    493 |  <A HREF="http://en.wikipedia.org/wiki/Mars_Exploration_Rover">Mars rovers</A>.
 | 
|  |    494 |  Actually, the very first Mars rover mission in 1997 did not have this
 | 
|  |    495 |  algorithm switched on and it almost caused a catastrophic mission failure (see
 | 
|  |    496 |  this youtube video <A HREF="http://www.youtube.com/watch?v=lyx7kARrGeM">here</A>
 | 
|  |    497 |  for an explanation what happened).
 | 
|  |    498 |  We were able to prove the correctness of this algorithm, but were also able to
 | 
|  |    499 |  establish the correctness of some optimisations in this
 | 
| 522 |    500 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/Publications/pip.pdf">paper</A>.
 | 
| 520 |    501 |  </p>
 | 
|  |    502 | 
 | 
|  |    503 |  <p>On a much smaller scale, there are a few small programs and underlying algorithms where it
 | 
|  |    504 |  is not really understood whether they always compute a correct result (for example the
 | 
|  |    505 |  regular expression matcher by Sulzmann and Lu in project [CU1]). The aim of this
 | 
|  |    506 |  project is to completely specify an algorithm in Isabelle and then prove it correct (that is,
 | 
|  |    507 |  it always computes the correct result).
 | 
|  |    508 | </p>
 | 
|  |    509 | 
 | 
|  |    510 |   <p>
 | 
|  |    511 |   <B>Skills:</B> 
 | 
|  |    512 |   This project is for a very good student with a knack for theoretical things and formal reasoning.
 | 
|  |    513 |   </p>
 | 
|  |    514 | 
 | 
|  |    515 | <li> <H4>[CU7] Anything Security Related that is Interesting</H4>
 | 
|  |    516 |   
 | 
|  |    517 | <p>
 | 
|  |    518 | If you have your own project that is related to security (must be
 | 
|  |    519 | something interesting), please propose it. We can then have a look
 | 
|  |    520 | whether it would be suitable for a project.
 | 
|  |    521 | </p>
 | 
|  |    522 | 
 | 
|  |    523 | <li> <H4>[CU8] Anything Interesting in the Areas</H4>
 | 
|  |    524 |   
 | 
|  |    525 | <ul>
 | 
|  |    526 | <li><A HREF="http://elm-lang.org">Elm</A> (a reactive functional language for animating webpages; have a look at the cool examples, or <A HREF="http://pragmaticstudio.com/blog/2014/12/19/getting-started-with-elm">here</A> for an introduction)
 | 
|  |    527 | <li><A HREF="http://www.smlserver.org/smltojs/">SMLtoJS</A> (a ML compiler to JavaScript; or anything else related to
 | 
|  |    528 |   sane languages that compile to JavaScript)
 | 
|  |    529 | <li>Any statistical data related to Bitcoins (in the spirit of this
 | 
|  |    530 | <A HREF="http://people.csail.mit.edu/spillai/data/papers/bitcoin-transaction-graph-analysis.pdf">paper</A> or
 | 
|  |    531 |   this <A HREF="https://eprint.iacr.org/2012/584.pdf">one</A>; this will probably require some extensive C knowledge or any
 | 
|  |    532 |   other heavy-duty programming language)
 | 
|  |    533 | <li>Anything related to programming languages and formal methods (like
 | 
|  |    534 |   <A HREF="http://matt.might.net/articles/intro-static-analysis/">static program analysis</A>)  
 | 
|  |    535 | <li>Anything related to low-cost, hands-on hardware like Raspberry Pi, Arduino,
 | 
|  |    536 |   <A HREF="http://en.wikipedia.org/wiki/Cubieboard">Cubieboard</A>
 | 
|  |    537 | <li>Anything related to unikernel operating systems, like
 | 
|  |    538 |   <A HREF="http://www.xenproject.org">Xen</A> or
 | 
|  |    539 |   <A HREF="http://www.openmirage.org">Mirage OS</A>
 | 
|  |    540 | <li>Any kind of applied hacking, for example the Arduino-based keylogger described
 | 
|  |    541 |    <A HREF="http://samy.pl/keysweeper/">here</A>
 | 
|  |    542 | <li>Anything related to code books, like this
 | 
|  |    543 |    <A HREF="http://www.joelotter.com/kajero/">one</A>
 | 
|  |    544 | </ul>
 | 
|  |    545 | 
 | 
|  |    546 | 
 | 
|  |    547 | 
 | 
|  |    548 | <li> <H4>Earlier Projects</H4>
 | 
|  |    549 | 
 | 
|  |    550 |  I am also open to project suggestions from you. You might find some inspiration from my earlier projects:
 | 
| 522 |    551 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/bsc-projects-12.html">BSc 2012/13</A>, 
 | 
|  |    552 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-12.html">MSc 2012/13</A>, 
 | 
|  |    553 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/bsc-projects-13.html">BSc 2013/14</A>,
 | 
|  |    554 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-13.html">MSc 2013/14</A>, 
 | 
|  |    555 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/bsc-projects-14.html">BSc 2014/15</A>,
 | 
|  |    556 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-14.html">MSc 2014/15</A>, 
 | 
|  |    557 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/bsc-projects-15.html">BSc 2015/16</A>,
 | 
|  |    558 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-15.html">MSc 2015/16</A>, 
 | 
|  |    559 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/bsc-projects-16.html">BSc 2016/17</A>,
 | 
|  |    560 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-16.html">MSc 2016/17</A>
 | 
|  |    561 |  <A HREF="https://nms.kcl.ac.uk/christian.urban/msc-projects-17.html">BSc 2017/18</A>
 | 
| 520 |    562 | </ul>
 | 
|  |    563 | </TD>
 | 
|  |    564 | </TR>  
 | 
|  |    565 | </TABLE>
 | 
|  |    566 |         
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|  |    567 | <P>
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|  |    568 | Time-stamp: <- 2017-09-27 12:44:13 by Christian Urban>
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|  |    569 | <a href="https://validator.w3.org/check/referer">[Validate this page.]</a>
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|  |    570 | </P>
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|  |    571 | </BODY>
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|  |    574 |  
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|  |    575 |  
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