@InProceedings{Murakami09,
  title =        "{O}n {C}ongruence {P}roperty of {S}cope {E}quivalence for {C}oncurrent {P}rograms with {H}igher-{O}rder {C}ommunication",
  author=        "Murakami,  Masaki",
  editor=        "Welch, Peter H. and Roebbers,  Herman and Broenink,  Jan F. and Barnes,  Frederick R. M. and Ritson,  Carl G. and Sampson,  Adam T. and Stiles,  G. S. and Vinter,  Brian",
  pages =        "49--66",
  booktitle=     "{C}ommunicating {P}rocess {A}rchitectures 2009",
  isbn=          "978-1-60750-065-0",
  year=          "2009",
  month=         "nov",
  abstract=      "Representation of scopes of names is important for analysis
     and
verification of concurrent systems.  However, it is
     difficult to
represent the scopes of channel names precisely
     with models based on
process algebra.  We introduced a model
     of concurrent systems with
higher-order communication based
     on graph rewriting in our previous
work.  A bipartite
     directed acyclic graph represents a concurrent
system that
     consists of a number of processes and messages in
     that
model. The model can represent the scopes of local
     names precisely.
We defined an equivalence relation such
     that two systems are
equivalent not only in their behavior
     but in extrusion of scopes of
names. This paper shows that
     the equivalence relation is a
congruence relation wrt
     tau-prefix, new-name, replication and
composition even if
     higher-order communication is allowed.  And we
also show the
     equivalence relation is not congruent wrt
     input-prefix
though it is congruent wrt input prefix in
     first-order case."
}