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991.
Data collection, both automatic and manual, lies at the heart of all empirical studies. The quality of data collected from
software informs decisions on maintenance, testing and wider issues such as the need for system re-engineering. While of the
two types stated, automatic data collection is preferable, there are numerous occasions when manual data collection is unavoidable.
Yet, very little evidence exists to assess the error-proneness of the latter. Herein, we investigate the extent to which manual
data collection for Java software compared with its automatic counterpart for the same data. We investigate three hypotheses
relating to the difference between automated and manual data collection. Five Java systems were used to support our investigation.
Results showed that, as expected, manual data collection was error-prone, but nowhere near the extent we had initially envisaged.
Key indicators of mistakes in manual data collection were found to be poor developer coding style, poor adherence to sound
OO coding principles, and the existence of relatively large classes in some systems. Some interesting results were found relating
to the collection of public class features and the types of error made during manual data collection. The study thus offers
an insight into some of the typical problems associated with collecting data manually; more significantly, it highlights the
problems that poorly written systems have on the quality of visually extracted data. 相似文献
992.
《Journal of Systems Architecture》2007,53(9):629-643
In this work we present a self-reconfiguration control focused on multiprocessor core-based systems implemented on FPGA technology. An infrastructure of signals, protocols, interfaces and a controller is exposed to perform safe hardware/software reconfigurations. This infrastructure is part of the Tornado framework that includes other elements such as a multi-context assembler for a reconfigurable processor or a custom design flow developed for the Wishbone IP-Core interconnection specification. We present two applications where the presented control system has been applied, and it is compared with other available approaches. 相似文献
993.
Sum versus vote fusion in multiple classifier systems 总被引:2,自引:0,他引:2
Kittler J. Alkoot F.M. 《IEEE transactions on pattern analysis and machine intelligence》2003,25(1):110-115
Amidst the conflicting experimental evidence of superiority of one over the other, we investigate the Sum and majority Vote combining rules in a two class case, under the assumption of experts being of equal strength and estimation errors conditionally independent and identically distributed. We show, analytically, that, for Gaussian estimation error distributions, Sum always outperforms Vote. For heavy tail distributions, we demonstrate by simulation that Vote may outperform Sum. Results on synthetic data confirm the theoretical predictions. Experiments on real data support the general findings, but also show the effect of the usual assumptions of conditional independence, identical error distributions, and common target outputs of the experts not being fully satisfied. 相似文献
994.
995.
《International Journal of Fatigue》2007,29(9-11):2040-2049
The fatigue-fretting damage parameter (FFDP) introduced by Ruiz is comprehensively discussed in this paper. Shortcomings and limitations of this criterion are presented resulting in a combined energetic-multiaxial enhancement (eFFDP). Specific frictional power was supposed to control the fretting damage and the critical plane approach is used to solve the multiaxial stress state in the fretting contact. The significance of the eFFDP is evaluated for the key–shaft–hub connection under combined torque and bend loading. Applying the analysis to recent fatigue tests, a comparison of stress and fretting parameters is made for different loading conditions including estimation of the fretting fatigue limit. 相似文献
996.
997.
998.
Demosthenes Kivotides 《Journal of Low Temperature Physics》2007,148(3-4):287-291
We analyse a numerical solution of a mathematical model of thermal superfluid turbulence. We elaborate on key points of the
statistical phenomenology and point out their impact on fundamental issues of general turbulence theory. 相似文献
999.
Dilute solution viscometry was used to explore the effect of solid-state ageing on the interactions that occur between guar
gum and water. The resulting data set, derived from nearly 700 independent experiments, led to a value for the Flory–Huggins
interaction parameter, χ, of 0.56 ± 0.12. This value, which appeared independent of ageing, is in good agreement with the
majority of published data. The effect of ageing on molar mass was also explored, using Mark–Houwink–Sakurada (MHS) theory.
Absolute molar mass values were found to depend sensitively on the choice of MHS constants, but the effect of ageing was unequivocal;
under all conditions, it resulted in a pronounced decrease in molar mass. In concert, these results strongly suggest that,
in guar, solid-state ageing reactions are largely associated with scission of the molecular backbone. This hypothesis was
then tested by infra-red and Raman spectroscopy. Although infra-red spectroscopy did reveal some subtle differences between
the spectra of guar and locust bean gum (LBG), a related polysaccharides with a different galactose:mannose ratio, no equivalent
effects were seen in aged guar. However, clear differences between the Raman spectra of guar and LBG were seen, demonstrating
that the technique is well capable of revealing changes in galactose:mannose ratios. Examination of aged guar samples revealed
no comparable effects, reinforcing the notion that, in this polysaccharide, chain scission reactions dominate such that solid-state
ageing does not lead to changes in the nature of its interaction with water. 相似文献
1000.