5,185 research outputs found
ConSIT: A conditioned program slicer
Conditioned slicing is a powerful generalisation of static and dynamic slicing which has applications to many problems in software maintenance and evolution, including reuse, reengineering and program comprehension. However there has been relatively little work on the implementation of conditioned slicing. Algorithms for implementing conditioned slicing necessarily involve reasoning about the values of program predicates in certain sets of states derived from the conditioned slicing criterion, making implementation particularly demanding. The paper introduces ConSIT, a conditioned slicing system which is based upon conventional static slicing, symbolic execution and theorem proving. ConSIT is the first fully automated implementation of conditioned slicing. An implementation of ConSIT is available for experimentation at &http://www.mcs.gold.ac.uk/tilde/~mas01sd/consit.htm
Mixing and merging for spoken document retrieval
This paper describes a number of experiments that explo-
red the issues surrounding the retrieval of spoken documents. Two such
issues were examined. First, attempting to find the best use of speech
recogniser output to produce the highest retrieval effectiveness. Second,
investigating the potential problems of retrieving from a so-called "mi-
xed collection", i.e. one that contains documents from both a speech
recognition system (producing many errors) and from hand transcription (producing presumably near perfect documents). The result of the
first part of the work found that merging the transcripts of multiple
recognisers showed most promise. The investigation in the second part
showed how the term weighting scheme used in a retrieval system was
important in determining whether the system was affected detrimentally
when retrieving from a mixed collection
Nuclear-size self-energy and vacuum-polarization corrections to the bound-electron g factor
The finite nuclear-size effect on the leading bound-electron g factor and the
one-loop QED corrections to the bound-electron g factor is investigated for the
ground state of hydrogen-like ions. The calculation is performed to all orders
in the nuclear binding strength parameter Z\alpha\ (where Z is the nuclear
charge and \alpha\ is the fine structure constant) and for the Fermi model of
the nuclear charge distribution. In the result, theoretical predictions for the
isotope shift of the 1s bound-electron g factor are obtained, which can be used
for the determination of the difference of nuclear charge radii from
experimental values of the bound-electron g factors for different isotopes
Program simplification as a means of approximating undecidable propositions
We describe an approach which mixes testing, slicing, transformation and formal verification to investigate speculative hypotheses concerning a program, formulated during program comprehension activity. Our philosophy is that such hypotheses (which are typically undecidable) can, in some sense, be `answered' by a partly automated system which returns neither `true' nor `false' but a program (the `test program') which computes the answer. The motivation for this philosophy is the way in which, as we demonstrate, static analysis and manipulation technology can be applied to ensure that the resulting test program is significantly simpler than the original program, thereby simplifying the process of investigating the original hypothesi
QED calculation of the nuclear magnetic shielding for hydrogen-like ions
We report an ab initio calculation of the shielding of the nuclear magnetic
moment by the bound electron in hydrogen-like ions. This investigation takes
into account several effects that have not been calculated before (electron
self-energy, vacuum polarization, nuclear magnetization distribution), thus
bringing the theory to the point where further progress is impeded by the
uncertainty due to nuclear-structure effects. The QED corrections are
calculated to all orders in the nuclear binding strength parameter and,
independently, to the leading order in the expansion in this parameter. The
results obtained lay the ground for the high-precision determination of nuclear
magnetic dipole moments from measurements of the g-factor of hydrogen-like
ions
Status of Ferro Alloy Industry in the Liberalised Economy
I wish you a very good morning and look forward to a very interesting and frank exchange of ideas during the next two days for the benefit of the FERRO ALLOYS INDUSTRY in our country.
I consider it a great honour and privilege that the National Metallurgical Laboratory and Jamshedpur chapter of Indian Institute of Metals have given me
this opportunity to present the Inaugural Address at the National workshop on "The Status of Ferro Alloys Industry in the Liberalised Economy"
Electron-correlation effects in the -factor of light Li-like ions
We investigate electron-correlation effects in the -factor of the ground
state of Li-like ions. Our calculations are performed within the
nonrelativistic quantum electrodynamics (NRQED) expansion up to two leading
orders in the fine-structure constant , and . The
dependence of the NRQED results on the nuclear charge number is studied and
the individual -expansion contributions are identified. Combining the
obtained data with the results of the all-order (in ) calculations
performed within the expansion, we derive the unified theoretical
predictions for the -factor of light Li-like ions.Comment: 9 pages, 4 table
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