Papers by Keyword: Defect Distribution

Abstract: Effective defect prediction is an important topic in software engineering. This paper studies multiple defect prediction models and proposes a defect prediction model during the test period for organic project. This model is based on the analysis of project defect data and refer to Rayleigh model. Defect prediction model plays an important role in the analysis of software quality, rationally allocating resources of software test, improving the efficiency of software test. This paper selected representative software defect data to apply this model, which has been shown to improve project performance.

Abstract: The defect distribution in 4H-SiC single crystals in dependence on the seed polarity and its off-orientation was investigated by KOH-etching, optical microscopy and X-ray topography. Micropipe density, stacking fault density and dislocation density were determined for 2” crystals grown in <000-1> direction 0 - 7° off towards <11-20> and for crystals up to 1” in diameter grown in <11-20> or a- and <1-100> or m-directions and using repeated a-face growth. For the growth in polar directions the micropipe density and dislocation density decrease with increasing offorientation of the seed. A similar behavior was found for the stacking fault density and dislocation density in non-polar directions with off-orientation to c-direction. Nevertheless, while the dislocation density could be reduced up to three orders of magnitude for the growth along non-polar directions, the stacking fault density was continuously increasing. Additionally, the defect distribution after repeated a-face growth will be discussed in terms of growth related and kinetic models.