| 260 |      1 | 
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|  |      3 | Dear Professor ???
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|  |      4 | 
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|  |      5 | I have recently been appointed as a University Lecturer
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|  |      6 | at King's College London. I know Chunhan Wu from my earlier 
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|  |      7 | work with Professor Xingyuan Zhang on regular languages and
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|  |      8 | the Isabelle theorem prover. This work led to a highly 
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|  |      9 | regarded publication at an international conference and
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|  |     10 | we also submitted a journal version of this work. In
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|  |     11 | both publications, Chunhan did much of the work and
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|  |     12 | has been the first author of the papers.
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|  |     13 | 
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| 261 |     14 | I like to invite Chunhan to work with me in London for 11 months. 
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|  |     15 | His living expenses for the stay will be covered by
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| 260 |     16 | my grant at King's College London. He would work with me
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|  |     17 | on improving the reasoning in the Isabelle theorem prover.
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|  |     18 | I can teach him the internals of this theorem prover so 
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|  |     19 | that he can independently implement his own work. To do this
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|  |     20 | effectively it would be most convenient for us if Chunhan
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|  |     21 | can be at King's College London. I can also introduce him 
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|  |     22 | there to the research community in the field of automated 
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|  |     23 | reasoning. I have worked and got to know
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|  |     24 | well researchers in Cambridge and in Munich, where the
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|  |     25 | theorem prover Isabelle is mainly developed and which
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|  |     26 | are centres of excellence in the field of automated
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| 261 |     27 | reasoning. During these 11 months, Chunhan and I would
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| 260 |     28 | work on projects which we hope can be published at
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|  |     29 | top-tier conferences.
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|  |     30 | 
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| 261 |     31 | I kindly request that you grant 11 months leave to
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| 260 |     32 | Chunhan. I am sure this scientific visit will be
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|  |     33 | invaluable for his career. He is a bright researcher
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|  |     34 | who will benefit greatly from collaboration with
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| 261 |     35 | established researchers in the field of automated reasoning. 
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| 260 |     36 | In due course when all bureaucratic hurdles are taken
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|  |     37 | the Head of the Informatics Department of King's College 
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|  |     38 | will also write to you supporting the request to
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| 261 |     39 | invite Chunhan to work with me in London.
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| 260 |     40 | 
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|  |     41 | 
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|  |     42 | Yours sincerely, 
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|  |     43 | Dr Christian Urban
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|  |     44 | 
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|  |     45 | 
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|  |     46 | PS: Please find attach an outline of the working plan
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|  |     47 | between Chunhan Wu and me.  
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|  |     48 | 
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|  |     49 | 
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|  |     50 | Work Plan
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|  |     51 | =========
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|  |     52 | 
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|  |     53 | - We first want to investigate how the datatype package
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|  |     54 |   of the Isabelle theorem prover can be made more expressive 
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|  |     55 |   and more efficient. Chunhan in his current work already
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|  |     56 |   went to the limits of the capabilities of this package.
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|  |     57 |   I have some preliminary results how this state of affairs
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|  |     58 |   can be improved and I would work with Chunhan to implement
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|  |     59 |   these results. This work is on the cutting edge of research
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|  |     60 |   in this field and the hope is it will be published in 
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|  |     61 |   top-tier conferences and journals.
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|  |     62 | 
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|  |     63 | - The second project is about making the Isabelle theorem
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|  |     64 |   prover more like a programming environment: programmers should 
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|  |     65 |   be able to write their code inside a theorem prover, verify 
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|  |     66 |   properties about the code and then compile it to efficient 
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|  |     67 |   machine code preserving the guaranties obtained by the verification. 
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|  |     68 |   These systems are desirable because they can make it cost-effective 
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|  |     69 |   to verify the functional behaviour of software and allow errors to 
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|  |     70 |   be detected early during program development. However, to
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|  |     71 |   complete this project we will have to make changes to the
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|  |     72 |   HOL-logic underlying the Isabelle theorem provers. This 
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|  |     73 |   is a long-term project which will stretch beyond the time
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|  |     74 |   Chunhan can stay in London. But the hope is that preliminary
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|  |     75 |   results can already be submitted for publication.
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|  |     76 | 
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|  |     77 | - Finally, I like to continue with Chunhan on our work
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|  |     78 |   about formalising regular expressions and the Myhill-Nerode theorem.
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|  |     79 |   There are still a number of question open, for example how this
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|  |     80 |   work can be extended to parsing algorithms. 
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|  |     81 | 
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