RE J1034+396: The origin of the soft X-ray excess and QPO (2008)
Middleton, Matthew, Done, Chris, Ward, Martin, Gierlinski, Marek, Schurch, Nick
The X-ray quasi-periodic oscillation (QPO) seen in RE J1034+396 is so far unique amongst AGN. Here we look at the another unique feature of RE J1034+396, namely its huge soft X-ray excess, to see if...
A ~1-hour X-ray periodicity in an active galaxy RE J1034+396 (2008)
Gierlinski, Marek, Middleton, Matthew, Ward, Martin, Done, Chris
Active galactic nuclei and quasars are thought to be scaled up versions of Galactic black hole binaries, powered by accretion onto supermassive black holes with masses of 10^6-10^9 M_Sun, as opposed...
Conditioned Semantic Slicing for Abstraction; Industrial Experiment † (2008)
Martin Ward, Hussein Zedan, Matthias Ladkau, Stefan Natelberg
One of the most challenging tasks a programmer can face is attempting to analyse and understand a legacy assembler system. Many features of assembler make analysis difficult, and these are the same...
Slicing as a Program Transformation (2007)
The aim of this paper is to provide a unified mathematical framework for program slicing which places all slicing work, for sequential programs, on a sound theoretical foundation. The main advantage...
and Meta-Transformations in the FermaT Transformation System (2005)
Martin Ward And, Martin Ward, Hussein Zedan
A program transformation is an operation which can be applied to any program (satisfying the transformations applicability conditions) and returns a semantically equivalent program. In the FermaT...
MetaWSL and meta-transformations in the fermaT transformation system (2005)
A program transformation is an operation which can be applied to any program (satisfying the transformations applicability conditions) and returns a semantically equivalent program. In the FermaT...
ConSUS: A Light-Weight Program Conditioner (2004)
Sebastian Danicic Mohammed, Mohammed Daoudi, Chris Fox, Mark Harman, Rob M. Hierons, John R. Howroyd, ...
Program conditioning consists of identifying and removing a set of statements which cannot be executed when a condition of interest holds at some point in a program. It has been applied to problems...
Consus: A lightweight program conditioner (2004)
Sebastian Danicic, Mohammed Daoudi, Chris Fox, Mark Harman, Rob M. Hierons, John R. Howroyd, ...
Program conditioning consists of identifying and removing a set of statements which cannot be executed when a condition of interest holds at some point in a program. It has been applied to problems...
ConSUS: A Light-Weight Program Conditioner (2004)
Sebastian Danicic Mohammed, Mohammed Daoudi, Chris Fox, Mark Harman, Rob M. Hierons, John R. Howroyd, ...
Program conditioning consists of identifying and removing a set of statements which cannot be executed when a condition of interest holds at some point in a program. It has been applied to problems...
A Massive X-Ray Outflow from the Quasar PDS 456 (2003)
Reeves, James, O'Brien, Paul, Ward, Martin
We report on XMM-Newton spectroscopic observations of the luminous, radio-quiet quasar PDS 456. The hard X-ray spectrum of PDS 456 shows a deep absorption trough (constituting 50% of the continuum)...
In this paper we consider a particular class of algorithms which present certain difficulties to formal verification. These are algorithms which use a single data structure for two or more purposes,...
What does it mean to say that one program is “more abstract ” then another? What is “abstract ” about an abstract data type? What is the difference between a “high-level ” program and a...
1-5 micron imaging of 3CRR galaxies: The K-z relation and the geometry of the torus (2000)
Simpson, Chris, Ward, Martin, Wall, J. V.
It has been claimed by Taylor et al. that the low-redshift end of the K-z relation for radio galaxies is too bright by about half a magnitude due to contributions from the obscured quasar nuclei....
A Recursion Removal Theorem - Proof and Applications (1999)
In this paper we briey introduce a Wide Spectrum Language and its transformation theory and describe a recent success of the theory: a general recursion removal theorem. This theorem includes as...
Derivation of a Sorting Algorithm (1999)
Martin Ward, South Rd, Then P S
> nioj S. 2 An Example of an Algorithm Derivation In this section we sketch the derivation of a version of Hoare's Quicksort algorithm [3]. This illustrates the use of the join construct in...
Assembler to C Migration using the FermaT Transformation System (1999)
The FermaT transformation system, based on research carried out over the last twelve years at Durham University and Software Migrations Ltd., is an industrial-strength formal transformation engine...
Simpson, Chris, Ward, Martin, O'Brien, Paul, Reeves, James
We present infrared photometry and optical and infrared spectroscopy of the recently-discovered, extremely luminous nearby quasar PDS 456. A number of broad emission features are seen in the...
A Definition of Abstraction (1996)
ion Martin Ward Computer Science Dept Science Labs South Rd Durham DH1 3LE April 9, 1996 Abstract What does it mean to say that one program is "more abstract" then another? What is...
In this paper we consider a particular class of algorithms which present certain difficulties to formal verification. These are algorithms which use a single data structure for two or more purposes,...
Program Analysis by Formal Transformation (1996)
Martin Ward, M. P. Ward, South Rd
This paper treats Knuth and Szwarcfiter's topological sorting program, presented in their paper "A Structured Program to Generate All Topological Sorting Arrangements" (Knuth and...
A Multipurpose Backtracking Algorithm (1994)
Hilary Priestley, Martin Ward, H. A. Priestley, St. Giles, M. P. Ward, South Rd
A backtracking algorithm with element order selection is presented, and its efficiency discussed in relation both to standard examples and to examples concerning relation-preserving maps which the...
Using Formal Transformations to Construct a Component Repository (1993)
Martin Ward, Dr. Martin Ward, South Rd
This paper discusses how theoretical results from the field of program transformations can be applied to develop a new approach to software reuse. We describe a model for the semantics of...
Abstracting a Specification from Code (1993)
Much of the work on developing program transformation systems has concentrated on systems to assist in program development. However, the four separate surveys carried out between 1977 and 1990...
Understanding Concurrent Programs using Program Transformations (1993)
Eddy Younger, Martin Ward, E. J. Younger, M. P. Ward
Reverse engineering of concurrent real-time programs with timing constraints is a particularly challenging research area, because the functional behaviour of a program, and the non-functional timing...
A Recursion Removal Theorem (1992)
In this paper we briefly introduce a Wide Spectrum Language and its transformation theory and describe a recent success of the theory: a general recursion removal theorem. Recursion removal often...
Thesis (M.A.)--Loma Linda University Riverside, 1990.
Proving program refinements and transformations / (1986)
Thesis (D. Phil.)--Oxford University, 1986.