@string{brics =	"{BRICS}"}
@string{daimi =	"Department of Computer Science, University of Aarhus"}
@string{iesd  =	"Department of Computer Science, Institute
		  of Electronic Systems, Aalborg University"}
@string{rs    =	"Research Series"}
@string{ns    =	"Notes Series"}
@string{ls    =	"Lecture Series"}
@string{ds    =	"Dissertation Series"}

@TechReport{BRICS-RS-07-18,
  author =	 "Midtgaard, Jan",
  title =	 "Control-Flow Analysis of Functional Programs",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-18",
  address =	 daimi,
  OPTkey =	 "",
  month =	 dec,
  note =	 "iii+38~pp",
  abstract =	 "We present a survey of control-flow analysis of
                  functional programs, which has been the subject of
                  extensive investigation throughout the past 25
                  years. Analyses of the control flow of functional
                  programs have been formulated in multiple settings
                  and have led to many different approximations,
                  starting with the seminal works of Jones, Shivers,
                  and Sestoft. In this paper we survey control-flow
                  analysis of functional programs by structuring the
                  multitude of formulations and approximations and
                  comparing them",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-17,
  author =	 "Aceto, Luca and Fokkink, Willem Jan and
                  Ing{\'o}lfsd{\'o}ttir, Anna",
  title =	 "A Cancellation Theorem for {7BCCSP}",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-17",
  address =	 "Reykjavik University",
  OPTkey =	 "",
  month =	 dec,
  note =	 "30~pp",
  abstract =	 "This paper presents a cancellation theorem for the
                  preorders in van Glabbeek's linear time-branching
                  time spectrum over BCCSP. Apart from having some
                  intrinsic interest, the proven cancellation result
                  plays a crucial role in the study of the cover
                  equations, in the sense of Fokkink and Nain, that
                  characterize the studied semantics. The techniques
                  used in the proof of the cancellation theorem may
                  also have some independent interest.",
  OPTlinkhtmlabs ="",
  OPTlinkdvi =	 "",
  OPTlinkps =	 "",
  OPTlinkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-16,
  author =	 "Danvy, Olivier and Millikin, Kevin",
  title =	 "On the Equivalence between Small-Step and Big-Step
                  Abstract Machines: A Simple Application of
                  Lightweight Fusion",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-16",
  address =	 daimi,
  OPTkey =	 "",
  month =	 nov,
  note =	 "ii+11~pp. To appear in {\em Information Processing
                  Letters} (extended version). Supersedes BRICS
                  RS-07-8",
  abstract =	 " We show how Ohori and Sasano's recent lightweight
                  fusion by fixed-point promotion provides a simple
                  way to prove the equivalence of the two standard
                  styles of specification of abstract machines: (1) in
                  small-step form, as a state-transition function
                  together with a `driver loop,' i.e., a function
                  implementing the iteration of this transition
                  function; and (2) in big-step form, as a
                  tail-recursive function that directly maps a given
                  configuration to a final state, if any. The
                  equivalence hinges on our observation that for
                  abstract machines, fusing a small-step specification
                  yields a big-step specification. We illustrate this
                  observation here with a recognizer for Dyck words,
                  the CEK machine, and Krivine's machine with
                  call/cc.\bibpar The need for such a simple proof is
                  motivated by our current work on small-step abstract
                  machines as obtained by refocusing a function
                  implementing a reduction semantics (a syntactic
                  correspondence), and big-step abstract machines as
                  obtained by CPS-transforming and then
                  defunctionalizing a function implementing a big-step
                  semantics (a functional correspondence).",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-15,
  author =	 "Lee, Jooyong",
  title =	 "A Case for Dynamic Reverse-code Generation",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-15",
  address =	 daimi,
  OPTkey =	 "",
  month =	 aug,
  note =	 "ii+10~pp",
  abstract =	 "Backtracking (i.e.\ reverse execution) helps the user
                  of a debugger to naturally think backwards along the
                  execution path of a program, and thinking backwards
                  makes it easy to locate the origin of a bug. So far
                  backtracking has been implemented mostly by state
                  saving or by checkpointing. These implementations,
                  however, inherently do not scale. As has often been
                  said, the ultimate solution for backtracking is to
                  use reverse code: executing the reverse code
                  restores the previous states of a program. In our
                  earlier work, we presented a method to generate
                  reverse code on the fly while running a
                  debugger. This article presents a case study of
                  dynamic reverse-code generation. We compare the
                  memory usage of various backtracking methods in a
                  simple but nontrivial example, a bounded-buffer
                  program. In the case of non-deterministic programs
                  such as this bounded-buffer program, our dynamic
                  reverse-code generation can outperform the existing
                  backtracking methods in terms of memory efficiency.",
  OPTlinkhtmlabs ="",
  OPTlinkdvi =	 "",
  OPTlinkps =	 "",
  OPTlinkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-14,
  author =	 "Danvy, Olivier and Spivey, Michael",
  title =	 "On {B}arron and {S}trachey's Cartesian Product
                  Function",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-14",
  address =	 daimi,
  OPTkey =	 "",
  month =	 jul,
  note =	 "ii+14~pp",
  abstract =	 "Over forty years ago, David Barron and Christopher
                  Strachey published a startlingly elegant program for
                  the Cartesian product of a list of lists, expressing
                  it with a three nested occurrences of the function
                  we now call \emph{foldr}. This program is remarkable
                  for its time because of its masterful display of
                  higher-order functions and lexical scope, and we put
                  it forward as possibly the first ever functional
                  pearl. We first characterize it as the result of a
                  sequence of program transformations, and then apply
                  similar transformations to a program for the
                  classical power set example. We also show that using
                  a higher-order representation of lists allows a
                  definition of the Cartesian product function where
                  \emph{foldr} is nested only twice.",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-13,
  author =	 "Lange, Martin",
  title =	 "Temporal Logics Beyond Regularity",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-13",
  address =	 daimi,
  OPTkey =	 "",
  month =	 jul,
  note =	 "82~pp",
  abstract =	 "Non-regular program correctness properties play an
                  important role in the specification of unbounded
                  buffers, recursive procedures, etc. This thesis
                  surveys results about the relative expressive power
                  and complexity of temporal logics which are capable
                  of defining non-regular properties. In particular,
                  it features Propositional Dynamic Logic of
                  Context-Free Programs, Fixpoint Logic with Chop, the
                  Modal Iteration Calculus, and Higher-Order Fixpoint
                  Logic.\bibpar Regarding expressive power we consider
                  two classes of structures: arbitrary transition
                  systems as well as finite words as a subclass of the
                  former. The latter is meant to give an intuitive
                  account of the logics' expressive powers by relating
                  them to known language classes defined in terms of
                  grammars or Turing Machines. \bibpar Regarding the
                  computational complexity of temporal logics beyond
                  regularity we focus on their model checking problems
                  since their satisfiability problems are all highly
                  undecidable. Their model checking complexities range
                  between polynomial time and non-elementary. ",
  OPTlinkhtmlabs ="",
  OPTlinkdvi =	 "",
  OPTlinkps =	 "",
  OPTlinkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-12,
  author =	 "Brodal, Gerth St{\o}lting and Fagerberg, Rolf and
                  J{\o}rgensen, Allan Gr{\o}nlund and Moruz, Gabriel and
                  M{\o}lhave, Thomas",
  title =	 "Optimal Resilient Dynamic Dictionaries",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-12",
  address =	 daimi,
  OPTkey =	 "",
  month =	 jul,
  OPTnote =	 "~pp",
  OPTabstract =	 "",
  OPTlinkhtmlabs ="",
  OPTlinkdvi =	 "",
  OPTlinkps =	 "",
  OPTlinkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-11,
  author =	 "Aceto, Luca and Ing{\'o}lfsd{\'o}ttir, Anna",
  title =	 "The Saga of the Axiomatization of Parallel
                  Composition",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-11",
  address =	 iesd,
  OPTkey =	 "",
  month =	 jun,
  note =	 "15~pp. To appear in the Proceedings of CONCUR 2007,
                  the 18th International Conference on Concurrency
                  Theory (Lisbon, Portugal, September 4--7, 2007),
                  Lecture Notes in Computer Science, Springer-Verlag,
                  2007",
  abstract =	 "This paper surveys some classic and recent results
                  on the finite axiomatizability of bisimilarity over
                  CCS-like languages. It focuses, in particular, on
                  non-finite axiomatizability results stemming from
                  the semantic interplay between parallel composition
                  and nondeterministic choice. The paper also
                  highlights the role that auxiliary operators, such
                  as Bergstra and Klop's left and communication merge
                  and Hennessy's merge operator, play in the search
                  for a finite, equational axiomatization of parallel
                  composition both for classic process algebras and
                  for their real-time extensions",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-10,
  author =	 "Brabrand, Claus and Giegerich, Robert and M{\o}ller,
                  Anders",
  title =	 "Analyzing Ambiguity of Context-Free Grammars",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-10",
  address =	 daimi,
  OPTkey =	 "",
  month =	 may,
  note =	 "17~pp. Full version of paper presented at CIAA~'07",
  abstract =	 "It has been known since 1962 that the ambiguity
                  problem for context-free grammars is
                  undecidable. Ambiguity in context-free grammars is a
                  recurring problem in language design and parser
                  generation, as well as in applications where
                  grammars are used as models of real-world physical
                  structures.\bibpar We observe that there is a simple
                  linguistic characterization of the grammar ambiguity
                  problem, and we show how to exploit this to
                  conservatively approximate the problem based on
                  local regular approximations and grammar
                  unfoldings. As an application, we consider grammars
                  that occur in RNA analysis in bioinformatics, and we
                  demonstrate that our static analysis of context-free
                  grammars is sufficiently precise and efficient to be
                  practically useful",
  linkhtmlabs =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-9,
  author =	 "Nielsen, Janus Dam and Schwartzbach, Michael I.",
  title =	 "The {SMCL} Language Specification",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-9",
  address =	 daimi,
  OPTkey =	 "",
  month =	 mar,
  OPTnote =	 "~pp",
  OPTabstract =	 "",
  OPTlinkhtmlabs ="",
  OPTlinkdvi =	 "",
  OPTlinkps =	 "",
  OPTlinkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-8,
  author =	 "Danvy, Olivier and Millikin, Kevin",
  title =	 "A Simple Application of Lightweight Fusion to
                  Proving the Equivalence of Abstract Machines",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-8",
  address =	 daimi,
  OPTkey =	 "",
  month =	 mar,
  note =	 "ii+6~pp",
  abstract =	 "We show how Ohori and Sasano's recent lightweight
                  fusion by fixed-point promotion provides a simple
                  way to prove the equivalence of the two standard
                  styles of specification of abstract machines: (1) as
                  a transition function together with a `driver loop'
                  implementing the iteration of this transition
                  function; and (2) as a function directly iterating
                  upon a configuration until reaching a final state,
                  if ever. The equivalence hinges on the fact that the
                  latter style of specification is a fused version of
                  the former one. The need for such a simple proof is
                  motivated by our recent work on syntactic
                  correspondences between reduction semantics and
                  abstract machines, using refocusing",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-7,
  author =	 "Danvy, Olivier and Millikin, Kevin",
  title =	 "Refunctionalization at Work",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-7",
  address =	 daimi,
  OPTkey =	 "",
  month =	 mar,
  note =	 "ii+16~pp. Invited talk at the 8th International
                  Conference on Mathematics of Program Construction,
                  MPC '06",
  abstract =	 "We present the left inverse of Reynolds's
                  defunctionalization and we show its relevance to
                  programming and to programming languages. We present
                  two methods to put a program that is almost in
                  defunctionalized form into one that is actually in
                  defunctionalized form, and we illustrate them with a
                  recognizer for Dyck words and with Dijkstra's
                  shunting-yard algorithm",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-6,
  author =	 "Danvy, Olivier and Millikin, Kevin and Nielsen,
                  Lasse R.",
  title =	 "On One-Pass {CPS} Transformations",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-6",
  address =	 daimi,
  OPTkey =	 "",
  month =	 mar,
  note =	 "ii+19~pp. Theoretical Pearl appeara in the {\em
                  Journal of Functional Programming}, 17(6), p.\
                  793--812, January 2007. Revised version of BRICS
                  RS-02-3",
  abstract =	 "We bridge two distinct approaches to one-pass CPS
                  transformations, i.e., CPS transformations that
                  reduce administrative redexes at transformation time
                  instead of in a post-processing phase. One approach
                  is compositional and higher-order, and is
                  independently due to Appel, Danvy and Filinski, and
                  Wand, building on Plotkin's seminal work. The other
                  is non-compositional and based on a reduction
                  semantics for the lambda-calculus, and is due to
                  Sabry and Felleisen. To relate the two approaches,
                  we use three tools: Reynolds's defunctionalization
                  and its left inverse, refunctionalization; a special
                  case of fold-unfold fusion due to Ohori and Sasano,
                  fixed-point promotion; and an implementation
                  technique for reduction semantics due to Danvy and
                  Nielsen, refocusing.\bibpar This work is directly
                  applicable to transforming programs into monadic
                  normal form.",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-5,
  author =	 "Aceto, Luca and Capobianco, Silvio and
                  Ing{\'o}lfsd{\'o}ttir, Anna",
  title =	 "On the Existence of a Finite Base for Complete Trace
                  Equivalence over {BPA} with Interrupt",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-5",
  address =	 iesd,
  OPTkey =	 "",
  month =	 feb,
  note =	 "26~pp",
  abstract =	 "We study Basic Process Algebra with interrupt modulo
                  complete trace equivalence. We show that, unlike in
                  the setting of the more demanding bisimilarity, a
                  ground complete finite axiomatization exists. We
                  explicitly give such an axiomatization, and extend
                  it to a finite complete one in the special case when
                  a single action is present",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-4,
  author =	 "St{\o}vring, Kristian and Lassen, S{\o}ren B.",
  title =	 "A Complete, Co-Inductive Syntactic Theory of
                  Sequential Control and State",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-4",
  address =	 daimi,
  OPTkey =	 "",
  month =	 feb,
  note =	 "36~pp. Appears in the proceedings of POPL 2007,
                  p. 161--172",
  abstract =	 "We present a new co-inductive syntactic theory,
                  eager normal form bisimilarity, for the untyped
                  call-by-value lambda calculus extended with
                  continuations and mutable references.\bibpar We
                  demonstrate that the associated bisimulation proof
                  principle is easy to use and that it is a powerful
                  tool for proving equivalences between recursive
                  imperative higher-order programs.\bibpar The theory
                  is modular in the sense that eager normal form
                  bisimilarity for each of the calculi extended with
                  continuations and/or mutable references is a fully
                  abstract extension of eager normal form bisimilarity
                  for its sub-calculi. For each calculus, we prove
                  that eager normal form bisimilarity is a congruence
                  and is sound with respect to contextual
                  equivalence. Furthermore, for the calculus with both
                  continuations and mutable references, we show that
                  eager normal form bisimilarity is complete: it
                  coincides with contextual equivalence.",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-3,
  author =	 "Aceto, Luca and Fokkink, Willem Jan and
                  Ing{\'o}lfsd{\'o}ttir, Anna",
  title =	 "Ready To Preorder: Get Your {BCCSP} Axiomatization for
                  Free!",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-3",
  address =	 iesd,
  OPTkey =	 "",
  month =	 feb,
  note =	 "37~pp",
  abstract =	 "This paper contributes to the study of the
                  equational theory of the semantics in van Glabbeek's
                  linear time - branching time spectrum over the
                  language BCCSP, a basic process algebra for the
                  description of finite synchronization trees. It
                  offers an algorithm for producing a complete
                  (respectively, ground-complete) equational
                  axiomatization of a behavioral congruence lying
                  between ready simulation equivalence and partial
                  traces equivalence from a complete (respectively,
                  ground-complete) inequational axiomatization of its
                  underlying precongruence---that is, of the
                  precongruence whose kernel is the equivalence. The
                  algorithm preserves finiteness of the axiomatization
                  when the set of actions is finite. It follows that
                  each equivalence in the spectrum whose
                  discriminating power lies in between that of ready
                  simulation and partial traces equivalence is
                  finitely axiomatizable over the language BCCSP if so
                  is its defining preorder",
  linkhtmlabs =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-2,
  author =	 "Aceto, Luca and Ing{\'o}lfsd{\'o}ttir, Anna",
  title =	 "Characteristic Formulae: From Automata to Logic",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-2",
  address =	 iesd,
  OPTkey =	 "",
  month =	 jan,
  note =	 "18~pp",
  abstract =	 "This paper discusses the classic notion of
                  characteristic formulae for processes using
                  variations on Hennessy-Milner logic as the
                  underlying logical specification language. It is
                  shown how to characterize logically (states of)
                  finite labelled transition systems modulo
                  bisimilarity using a single formula in
                  Hennessy-Milner logic with recursion. Moreover,
                  characteristic formulae for timed automata with
                  respect to timed bisimilarity and the faster-than
                  preorder of Moller and Tofts are offered in terms of
                  the logic $L_{\nu}$ of Laroussinie, Larsen and
                  Weise.",
  linkhtmlabs =	 "",
  linkdvi =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}

@TechReport{BRICS-RS-07-1,
  author =	 "Andersson, Daniel",
  title =	 "{HIROIMONO} is {NP}-complete",
  institution =	 brics,
  year =	 2007,
  type =	 rs,
  number =	 "RS-07-1",
  address =	 daimi,
  OPTkey =	 "",
  month =	 jan,
  note =	 "8~pp",
  abstract =	 "In a Hiroimono puzzle, one must collect a set of
                  stones from a square grid, moving along grid lines,
                  picking up stones as one encounters them, and
                  changing direction only when one picks up a
                  stone. We show that deciding the solvability of such
                  puzzles is NP-complete",
  linkhtmlabs =	 "",
  linkps =	 "",
  linkpdf =	 "",
  OPTannote =	 ""
}