A repairable system is a system that can be restored to an operational state after a repair event. The system may experience multiple events over time, which are called recurrent events. To model the recurrent event data, the renewal process (RP), the nonhomogeneous Poisson process (NHPP), and the trend-renewal process (TRP) are often used. Compared to the RP and NHPP, the TRP is more flexible ...

A lot of importance has been attached to the testing phase of the Software Development Life Cycle (SDLC). It is during this phase it is checked whether the software product meets user requirements or not. Any discrepancies that are identified are removed. But testing needs to be monitored to increase its effectiveness. Software Reliability Growth Models (SRGMs) that specify mathematical relatio...

I Abstract European cities spend in the order of one billion Euros a year to rehabilitate water supply networks. Rehabilitation costs will increase in the coming decades as networks age and deteriorate. The rational behind today’s rehabilitation decisions is unclear. In the best case, decisions are based on practical experience like failure frequency. During the past 10-20 years, most of the la...

Although several tools have been developed for the estimation of software reliability, they are highly specialized in the approaches they implement and the particular phase of the software life-cycle in which they are applicable. Also the conventional techniques for software reliability evaluation, which treat the software as a monolithic entity are inadequate to assess the reliability of heter...

Software reliability is one of the most important characteristics of software quality. Its measurement and management technologies employed during software life cycle are essential for producing and maintaining quality/reliable software systems. It can also be monitored efficiently using Statistical Process Control (SPC). It assists the software development team to identify and actions to be ta...

Traditional statistical analysis methods account for natural variation but require aggregation of measurements over time,which can delay decision making.Statistical process control (SPC) is a branch of statistics that combines rigorous time series analysis methods with graphical presentation of data,often yielding insights into the data more quickly and in a way more understandble to lay decisi...

In this paper, we propose a software reliability model that considers not only error generation but also fault removal efficiency combined with testing coverage information based on a nonhomogeneous Poisson process (NHPP). During the past four decades, many software reliability growth models (SRGMs) based on NHPP have been proposed to estimate the software reliability measures, most of which ha...

The efficiency of two Software Reliability growth models are analyzed. The most popular based on a non homogeneous Poisson process and the less known based on a compound Poisson process. Several experimental data are used in order to analyze the goodness of fit of both models. The importance of the estimation method for the parameters involved is also analyzed.