Browsing by Subject "Computer software--Reliability."

Now showing 1 - 2 of 2

Open Access
Architecture-driven fault-based testing for software safety
(2014) Gürbüz, Havva Gülay
A safety-critical system is defined as a system in which the malfunctioning of software could result in death, injury or damage to environment. To mitigate these serious risks the architecture of safety-critical systems need to be carefully designed and analyzed. A common practice for modeling software architecture is the adoption of architectural perspectives and software architecture viewpoint approaches. Existing approaches tend to be general purpose and do not explicitly focus on safety concern in particular. To provide a complementary and dedicated support for designing safety-critical systems we propose safety perspective and an architecture framework approach for software safety. Once the safety-critical systems are designed it is important to analyze these for fitness before implementation, installation and operation. Hereby, it is important to ensure that the potential faults can be identified and cost-effective solutions are provided to avoid or recover from the failures. In this context, one of the most important issues is to investigate the effectiveness of the applied safety tactics to safety-critical systems. Since the safety-critical systems are complex systems, testing of these systems is challenging and very hard to define proper test suites for these systems. Several fault-based software testing approaches exist that aim to analyze the quality of the test suites. Unfortunately, these approaches do not directly consider safety concern and tend to be general purpose and they doesn’t consider the applied the safety tactics. We propose a fault-based testing approach for analyzing the test suites using the safety tactic and fault knowledge.
Open Access
Modeling the software failure process and software reliability
(1996) Dayanık, Savaş
Бог the last few deccides, the computer systems have replaced the man power in many important areas of life. Financial markets, production and service systems are controlled either fully by the computers or by the managers who extensively use the computers. Therefore, a major failure of a computerized system iriciy end up with a catastrophe that may affect a hirge number of people adversely, for this reason, reliability of computer systems attracts tlie attention of the researchers and practitioners. Software is one of the major component of a computer system. Therefore, in this thesis, we study the stochastic nature of the failure process of a software during the debugging phase. We propose a mathematical model for the software fciilure process which may also lead to prediction of future reliability. Different from many other available software relicibility models, we particularly try to incorporate the structural properties of a softwcire such as the number ol its different instruction paths cuid their logical complexities. The debugging phase is assumed to be composed of successive test sessions. Distribution functions of the length of a test session and the remaining number ol faults cifter a test session are computed. A stopping condition lor the debugging phase is proposed.