An experimental examination of the role of re-engineering in the management of software quality

This paper reports on the design and the results of a randomised, controlled experiment estimating the effect of predetermined changes in module complexity on the maintainability of different program versions seeded with equivalent logic errors. The experiment measures maintainability which is a defining sub-attribute of quality. The hypothesis "low module complexity results in high maintainability" is tested experimentally by monitoring and recording the time taken to identify and correct the seeded errors. Prior to the experiment programs are statically analysed to produce measurements of internal sub-attributes of the fundamental attribute of complexity. A first program version is modularised according to established rules giving a new version with a larger number of modules and with smaller individual module complexity. The results of this work can be used to design tools capable of providing an indicator, or factor, for re-engineering whereby a given program can be restructured in such a way that quality improvement can be quantified or at least estimated. As maintainability is a defining attribute of quality the insights gained can be further applied in understanding the underlying processes involved and ultimately lead to quality improvements

What Powers the Compact Radio Emission in Nearby Elliptical and S0 Galaxies?

Many nearby early-type (elliptical and S0) galaxies contain weak (milli-Jansky level) nuclear radio sources on scales a few hundred parsecs or less. The origin of the radio emission, however, has remained unclear, especially in volume-limited samples that select intrinsically less luminous galaxies. Both active galactic nuclei and nuclear star formation have been suggested as possible mechanisms for producing the radio emission. This paper utilizes optical spectroscopic information to address this issue. A substantial fraction of the early-type galaxies surveyed with the Very Large Array by Wrobel & Heeschen (1991) exhibits detectable optical emission lines in their nuclei down to very sensitive limits. Comparison of the observed radio continuum power with that expected from the thermal gas traced by the optical emission lines implies that the bulk of the radio emission is nonthermal. Both the incidence and the strength of optical line emission correlate with the radio power. At a fixed line luminosity, ellipticals have stronger radio cores than S0s. The relation between radio power and line emission observed in this sample is consistent with the low-luminosity extension of similar relations seen in classical radio galaxies and luminous Seyfert nuclei. A plausible interpretation of this result is that the weak nuclear sources in nearby early-type galaxies are the low-luminosity counterparts of more powerful AGNs. The spectroscopic evidence supports this picture. Most of the emission-line objects are optically classified as Seyfert nuclei or low-ionization nuclear emission-line regions (LINERs), the majority of which are likely to be accretion-powered sources.Comment: LaTex, 16 pages including embedded figures. Accepted for publication in the Astrophysical Journa

Effects of amputation and Corynebacterium parvum on tumour metastases in mice.

The effects of operation (lower-limb amputation) on the growth of the Lewis lung tumour and its metastases were studied. The role of C. parvum in counteracting these effects was investigated. Anaesthesia alone or with amputation did not affect primary tumour growth. C. parvum depressed this growth. Anaesthesia did not affect the number of pulmonary metastases, but amputation caused a significant increase. C. parvum inhibited metastases and completely counteracted the effects of operation on them. Large doses of cortisone acetate significantly increased metastases but small doses had no effect. Experiments with adrenalectomized mice suggested the effects of operation were due to non-specific stress

An experimental examination of program maintainability as a function of structuredness

The general ethos of producing structured programs has been, at least in theory, adopted throughout the software engineering community. By studying and measuring the structure of existing software we can estimate the benefits to be gained from changes in the structure in terms of the external attributes (perceived behaviour) of the re- structured software. [13, 2, 3, 10, 6, 7]. In this paper we report the results of two controlled experiments measuring the improvement on the maintainability of differently structured code. These experiments build on the experience and insights gained through an earlier experiment [5]. We discuss a strategy for re-structuring based on an improved re-engineering factor [9] and present the static measures of morphology (depth and width of module calls), coupling and cohesion and module complexity of a range of programs. By plotting these measures and adopting target values (e.g. width of call< 5) we estimate the expected improvement in the maintainability after re-engineering. We subsequently carry out the re-engineering, measure the re-structured code statically and measure the actual maintainability experimentally. The results reveal that unstructured programmes take longer to 'reveal their secrets'. An integral part of this work are the design and execution of controlled experiments as well as the use of automated tools for the static analysis of code and the recording of the experimental data

Classroom assessment and education: challenging the assumptions of socialisation and instrumentality

The opportunity offered by the Umea Symposium to probe the intersection of quality and assessment immediately brings into focus a wider issue – that of the quality of education which assessment aspires to support. Prompted by recent research into formative assessment in Scottish primary school contexts, the paper explores how formative assessment has become associated with an overly benign understanding of learning which misrecognises the possibility of undesirable learning and does not seem to address the inherently political nature of education. Having illuminated the potential inequities of formative assessment practices, the paper then asks what role formative assessment might play to support an understanding of education that is not simply about the transmission of traditional social norms, but also aspires to illuminate their social construction and their political nature

Searching for Clusters of Galaxies with SUMSS

Statistical overdensities of radio sources in the NRAO VLA Sky Survey (NVSS) catalogue have proven to be signposts to high-redshift clusters of galaxies. A similar search for overdensities has been carried out in the Sydney University Molonglo Sky Survey (SUMSS), which is closely matched in resolution and frequency to the NVSS. Sixty potential southern-hemisphere clusters have been found in SUMSS

From treebank resources to LFG F-structures

We present two methods for automatically annotating treebank resources with functional structures. Both methods define systematic patterns of correspondence between partial PS configurations and functional structures. These are applied to PS rules extracted from treebanks, or directly to constraint set encodings of treebank PS trees

Evaluation of striped bass stocks in Virginia : monitoring and tagging studies, 2004-2008 Annual report 1 September 2003 - 31 August 2004

This report presents the results of striped bass (Marone saxatilis) tagging and monitoring activities in Virginia during the period 1 August 2003 through 31 August 2004. It includes an assessment of the biological characteristics of striped bass taken from the 2004 spring spawning run, estimates of annual survival based on annual spring tagging, and the results of the fall 2003 directed mortality study that is a collaborative effort with the Maryland Department ofNatural Resources. The information contained in this report is required by the Atlantic States Marine Fisheries Commission and is used to implement a coordinated management plan for striped bass in Virginia, and along the eastern seaboard