Dynamic Two-phase Truncated Rayleigh Model for Release Date Prediction of Software

Software reliability modeling and prediction are important issues during software development, especially when one has to reach a desired reliability prior to software release. Various techniques, both static and dynamic, are used for reliability modeling and prediction in the context of software risk management. The single-phase Rayleigh model is a dynamic reliability model;however, it is not suitable for software release date prediction. We propose a new multi-phase truncated Rayleigh model and obtain parameter estimation using the nonlinear least squares method. The proposed model has been successfully tested in a large software company for several software projects. It is shown that the two-phase truncated Rayleigh model outperforms the traditional single-phase Rayleigh model in modeling weekly software defect arrival data. The model is useful for project management in planning release times and defect management.

旋转的Rayleigh-Bénard问题的Lorenz模型及数值模拟

利用截谱方法,将旋转的Rayleigh-Bénard问题转化为四维的Lorenz模型,估计出此Lorenz模型的参数取值范围为τ∈[0,2],r∈(0,∞),b∈[0,8/3]。比较了四维Lorenz方程与经典的三维的Lorenz方程(无旋转)的不同之处,在此基础上进行了数值模拟,结果表明旋转可以增加系统稳定性。