A study into the effects of personality type and methodology on cohesion in software engineering teams

The aim of the research described in this paper is to gain a qualitative understanding of how cohesiveness relates to personality type, performance and adherence to a particular software engineering methodology (XP). A variety of research methods were employed including ethnographic methods, questionnaires and interviews. An online personality test based on the Myers-Briggs Type Indicator (MBTI) was used to ascertain the personality types, and questionnaires were used throughout the project to measure levels of cohesiveness. Examples of how the teams worked together throughout the project are described, and whether and how this relates to the personality types of the individual members. The results indicate that certain teams were found to work consistently well over the project due to homogeneity in personality type and others were found to be very cohesive due to a mixture of types.     

Generating Test Sets from Non-Deterministic Stream X-Machines

X-machines were proposed by Holcombe as a possible specification language and since then a number of further investigations have demonstrated that the model is intuitive and easy to use as well as general enough to cater for a wide range of applications. In particular (generalised) stream X-machines have been found to be extremely useful as a specification method and most of the theory developed so far has concentrated on this particular class of X-machines. Furthermore, a method for testing systems specified by stream X-machines exists and is proved to detect all faults of the implementation provided that the system meets certain initial requirements. However, this method can only be used to generate test sequences from deterministic X-machine specifications. In this paper we present the theoretical basis for a method for generating test sets from non-deterministic generalised stream X-machines. Received November 1999 / Accepted in revised form September 2000     

Minding the geotechnical data gap: appraisal of the variability of key soil parameters for slope stability modelling in Saint Lucia

Bulletin of Engineering Geology and the Environment - Identification of failure thresholds and critical uncertainties associated with slope stability often requires the specification of...     

Assessment of the risk of solar ultraviolet radiation to amphibians. I. Dose-dependent induction of hindlimb malformations in the northern leopard frog (Rana pipiens)

A number of environmental stressors have been hypothesized as responsible for recent increases in limb malformations in several species of North American amphibians. The purpose of this study was to generate dose-response data suitable for assessing the potential role of solar ultraviolet (UV) radiation in causing limb malformations in a species in which this phenomenon seemingly is particularly prevalent, the northern leopard frog (Rana pipiens). Frogs were exposed from early embryonic stages through complete metamorphosis to varying natural sunlight regimes, including unaltered (100%) sunlight, sunlight subjected to neutral density filtration to achieve relative intensities of 85%, 75%, 65%, 50%, and 25% of unaltered sunlight, and sunlight filtered with glass or acrylamide to attenuate, respectively, the UVB (290-320 nm) and UVB plus UVA (290-380 nm) portions of the spectrum. The experiments were conducted in a controlled setting, with continual monitoring of UVB, UVA, and visible light to support a robust exposure assessment. Full sunlight caused approximately 50% mortality of the frogs during early larval development; no significant treatment-related mortality occurred under any of the other exposure regimes, including 100% sunlight with glass or acrylamide filtration. There was a dose-dependent (p < 0.0001) induction of hindlimb malformations in the frogs, with the percentage of affected animals ranging from about 97% under unaltered sunlight to 0% in the 25% neutral density treatment. Malformations were comprised mostly of missing or truncated digits, and generally were bilateral as well as symmetrical. Filtration of sunlight with either glass or acrylamide both significantly reduced the incidence of malformed limbs. The estimated sunlight dose resulting in a 50% limb malformation rate (ED50) was 63.5%. The limb ED50 values based on measured sunlight intensities corresponded to average daily doses of 4.5 and 100 Wh x m(-2) for UVB and UVA, respectively. Exposure to sunlight also resulted in increased eye malformations in R. pipiens, however, the dose-response relationship for this endpoint was not monotonic. The results of this study, in conjunction with measured or predicted exposure data from natural settings, provide a basis for quantitative prediction of the risk of solar UV radiation to amphibians.     

Optimizing the multielement analysis capabilities of an ICP quadrupole mass spectrometer using electrothermal vaporization sample introduction

A mathematical solution and an experimental procedure are described for calculating the maximum number of transient signals, such as those obtained using ETV sample introduction into an ICPMS, that can be monitored by a scanning spectrometer, such as a quadrupole mass analyzer. The total number of masses that can be monitored per ETV firing is shown to be dependent on the values chosen for data collection (i.e., scan time and dwell time) and the necessary limits of detection required by the method. The theory shows the effect that statistical noise, peak shapes, and inconsistent peak appearance times have on the overall variance calculated for the sample concentration based on total counts or "peak area". Also included in the variance calculation is the contribution made by the autosampler as an example of one type of error that is not associated with the data collection parameters. The theory is validated by two experiments where 21 and 68 transient signals are monitored per ETV firing; and as predicted, a 10 ppb sample is accurately quantified with precision better than 9% in both cases.     

The Impact of an Agile Methodology on the Well Being of Development Teams

This paper describes an empirical study, which addresses the aspect of well being amongst members of the software development teams. The question of interest is whether an agile methodology has any distinct effect on the well being of the software developers. Both quantitative and qualitative methods were utilised, including the participative observation, focus group interviews, close-ended questionnaires and simple statistical tests such as Spearman Correlation and Mann–Whitney test. Initial results showed that an agile methodology (XP) has a positive effect on the level of enthusiasm of the software developers in the most dynamic project. To understand why XP can increase enthusiasm, results are interpreted with references to cognitive, affective and managerial properties of the practices studied. This result needs further investigation on the individual effects of each practice on the wellbeing and attitudes of Software Engineering (SE) teams.     

Thermophoretic collection and analysis of submicrometer ag particles emitted from a graphite tube-type electrothermal vaporizer

Using thermophoretic collection with a cooled Cu probe, particles generated in an electrothermal vaporizer (ETV) from a AgNO(3) solution sample have been collected and analyzed using transmission electron microscopy and high-energy electron diffraction (HEED). Ag particles are spherical and, interestingly, have diameters falling into one of four size regimes, <5, 15, 25, and >40 nm. An extremely large number (estimated at >10(8)) of particles with diameters of <100 nm are collected. For an aqueous AgNO(3) solution deposited in the ETV, the HEED pattern of the collected aerosol particles exiting the pulse heated ETV matched body centered cubic Ag((s)), and the large number of diffraction spots suggests that particles are composed of microcrystalline domains. The features of the particles confirm earlier predictions of homonucleation as the primary particle formation mechanism. "Groupings" of apparently disconnected particles were a unique feature seen from the pulse-heated vaporization of the dried sample. This morphology is unique and does not appear like any other clustering or aggregation of particles reported elsewhere. It is not clear what causes this particle grouping, although the absence of these groupings when a 700 °C thermal pretreatment step was introduced suggests that the AgNO(3) decomposition plays a role in their formation. It is suggested that the particles formed from homonucleation are created very near the graphite surface and are cooled quite rapidly to form the solid silver particles. A mechanism is presented to explain the appearance of silver in the gas phase at temperatures below the vaporization temperature for silver metal.     

Acral lentiginous melanoma

BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) may cause neuropathic bladder dysfunction due to spinal cord involvement. OPLL, unlike a traumatic spinal cord lesion, progresses insidiously and sometimes affects longer cord segments. As the manifestation of bladder dysfunction may depend on the development of OPLL, we studied the relationship between bladder function and roentgenographic changes in the spinal canals of OPLL patients. PATIENTS AND METHODS: Eighteen surgical candidates (11 males and 7 females, 34 to 85 years old) were studied urodynamically. Sixteen underwent CO2-filling cystometry, uroflowmetry and measurement of their residual urine volume. Cystometry was omitted in the remaining 2 patients. The vertical extent of OPLL and the degree of stenosis in the spinal canal was estimated by x-ray films and CT. RESULTS: The cystometric study revealed detrusor hyperreflexia in 2 patients and areflexic or underactive detrusors in 5 patients. Intermittent flows or considerable amounts of residual urine were also observed in the arefilexia/underactive group. Uroflowmetry showed a normal flow with little residual urine in both patients in whom cystometry was omitted. Bladder sensation was maintained in all patients. The occurrence of abnormal detrusor activity had no relationship to the degree of canal stenosis, while the occurrence of an areflexic or underactive detrusor correlated with the vertical extent of OPLL. CONCLUSION: Although detrusor hyperreflexia is common in an upper spinal cord lesion, attention should also be paid to the development of detrusor underactivity in patients with a wide vertical extent of OPLL.     

Coatings on graphite crucibles used in melting uranium

Standard coatings for graphite crucibles used for melting uranium have generally been zirconia based and have been applied as a paint or by flame spraying. These coatings do not provide adequate protection at the temperatures normally required for melting uranium alloys. Yttria provides superior protection above 1300°C but becomes less satisfactory above 1450°C when applied directly on graphite. The utilization of a protective niobium/zirconia bilayer coating between the yttria and the graphite results in improved performance at 1500°C. Yttria has been satisfactorily applied both by plasma spraying and by brush applying a stable suspension. When the protective niobium layer is used, coating adherence after melting is excellent and multiple use of coatings is practical. The coatings adhere to graphite with a high coefficient of thermal expansion (CTE) (≈7 μm m^-1 °C^-1) much better than to standard crucible grade graphite (≈4μm m^-1 °C^-1). A single Nb/Y₂O₃-coated high CTE graphite crucible has been used for seven melts at 1450°C without repair or increased carbon contamination.The yttria paint coating is cost effective when compared with flame- or plasma-sprayed zirconia.