“…Software faults which manifest permanently, also known as Bohrbugs, are likely to fix and discover during the pre-operational phases of system life cycle (e.g., structured design, design review, quality assurance, unit, component and integration testing, alpha/beta test), as well as by means of traditional debugging techniques. Conversely, software faults which manifest transiently, also known as Heisenbugs, cannot be reproduced systematically (Huang, Jalote, & Kintala, 1994), and they have been demonstrated to be the major cause of failures in software systems, especially during the system operational phase (Sullivan & Chillarege, 1991;Chillarege, Biyani, & Rosenthal,1995;Xu, Kalbarczyc, & Iyer, 1999).…”