Optimal test case selection for multi-component software system

The omnipresence of software has forced upon the industry to produce efficient software in a short time. These requirements can be met by code reusability and software testing. Code reusability is achieved by developing software as components/modules rather than a single block. Software coding teams are becoming large to satiate the need of massive requirements. Large teams could work easily if software is developed in a modular fashion. It would be pointless to have software that would crash often. Testing makes the software more reliable. Modularity and reliability is the need of the day. Testing is usually carried out using test cases that target a class of software faults or a specific module. Usage of different test cases has an idiosyncratic effect on the reliability of the software system. Proposed research develops a model to determine the optimal test case policy selection that considers a modular software system with specific test cases in a stipulated testing time. The proposed model, models the failure behavior of each component using a conditional NHPP (Non-homogeneous Poisson process) and the interactions of the components by a CTMC (continuous time Markov chain). The initial number of bugs and the bug detection rate are known distributions. Dynamic programming is used as a tool in determining the optimal test case policy. The complete model is simulated using Matlab. The Markov decision process is computationally intensive but the implementation of the algorithm is meticulously optimized to eliminate repeat calculations. This has saved roughly 25-40% in processing time for different variations of the problem

Applications of Bayesian networks and Petri nets in safety, reliability, and risk assessments: A review

YesSystem safety, reliability and risk analysis are important tasks that are performed throughout the system lifecycle to ensure the dependability of safety-critical systems. Probabilistic risk assessment (PRA) approaches are comprehensive, structured and logical methods widely used for this purpose. PRA approaches include, but not limited to, Fault Tree Analysis (FTA), Failure Mode and Effects Analysis (FMEA), and Event Tree Analysis (ETA). Growing complexity of modern systems and their capability of behaving dynamically make it challenging for classical PRA techniques to analyse such systems accurately. For a comprehensive and accurate analysis of complex systems, different characteristics such as functional dependencies among components, temporal behaviour of systems, multiple failure modes/states for components/systems, and uncertainty in system behaviour and failure data are needed to be considered. Unfortunately, classical approaches are not capable of accounting for these aspects. Bayesian networks (BNs) have gained popularity in risk assessment applications due to their flexible structure and capability of incorporating most of the above mentioned aspects during analysis. Furthermore, BNs have the ability to perform diagnostic analysis. Petri Nets are another formal graphical and mathematical tool capable of modelling and analysing dynamic behaviour of systems. They are also increasingly used for system safety, reliability and risk evaluation. This paper presents a review of the applications of Bayesian networks and Petri nets in system safety, reliability and risk assessments. The review highlights the potential usefulness of the BN and PN based approaches over other classical approaches, and relative strengths and weaknesses in different practical application scenarios.This work was funded by the DEIS H2020 project (Grant Agreement 732242)

Biometrics system reliability evaluation method

Biometrijski sustavi ulaze u sve češću i rašireniju uporabu od 2003. godine, kada naputak o primjeni istih, u domeni uporabe u svrhu jačanja nacionalne sigurnosti, biva ugrađen u strategiju nacionalne sigurnosti EU, SAD te mnogih drugih zemalja. Motivi za primjenu biometrijskih sustava, posebno u domeni mjera nacionalne sigurnosti, često otvaraju niz pitanja iz područja povjerenja u svrhu korištenja prikupljenih podataka čime se u mnogim situacijama zadire u sferu potencijalnog kompromitiranja i narušavanja privatnosti osoba. Procesi standardizacije biometrijskih antropometrijskih sustava, kao preduvjet za povećanje povjerenja korisnika sustava, aktualni posljednjih godina, uglavnom se fokusiraju na definiranje određenih tehničkih značajki sustava bez eksplicitnog definiranja zahtjeva kvalitete funkcioniranja samih biometrijskih sustava. Pouzdanost biometrijskih sustava jedan je od temeljnih parametara za ocjenu kvalitete istih te sukladno tomu prijedlog budućeg znanstvenog istraživanja biti će utemeljen na povezivanju postojećih saznanja glede evaluacije pouzdanosti biometrijskih sustava s aspekta tehnologije sustava, okoline uporabe te korisnika sustava s ciljem definiranja metode za evaluaciju pouzdanosti utemeljenoj na ontologiji. U radu je dan pregled postojećih modela evaluacije pouzdanosti te razvijen evaluacijski model OOEPBS (otvoreni okvir za evaluaciju pouzdanosti biometrijskih sustava) utemeljen na definiranoj metodi za evaluaciju pouzdanosti biometrijskih sustava. Na temelju evaluacijskog modela OOEPBS izgrađena je ontologija čija je krovna domena biometrijska znanost sa specijalizacijom koncepata koji pokrivaju problematike evaluacije pouzdanosti biometrijskih sustava. Realizirana je također i provjera valjanosti te vrednovanje izgrađene ontologije, te su kreirane i instance koje su poslužile za testiranje okvira.The widespread usage of biometric systems is gaining momentum after 2003., when their utilization, within enforcement national security process, has been ordered and built into security strategies of the E.U., U.S.A., and many other countries. The motives for the utilization of such systems with emphasis on preserving national security, often raises a number of questions in the domain of privacy concerns regarding the potential misuse of the collected data, thus often penetrating into the sphere of potential compromising of users privacy. On the other hand, biometric system's standardization processes, which should be a prerequisite for increasing the users' confidence into the systems, predominantly focuses on defining certain technical features, without explicitly defining quality requirements. Reliability of biometric system is one of the fundamental parameters for evaluating the quality of the same, followed by the proposal of future scientific research will be based on linking existing knowledge regarding the evaluation of the reliability of biometric systems in terms, customer motivation, motivation of use of technology, the environment, usability and performance evaluation parameters with the aim of defining method for evaluating reliability based on ontology. An overview of actual evaluation models is presented in this doctoral thesis and also is developed an evaluation model OOEPBS (open framework for reliability evaluation for biometric systems) based on the reliability evaluation method for biometric systems. OOEPBS evaluation model has served for the development of the ontology with domain in biometrical science and specialization of the concepts within the reliability evaluation area. Ontology is evaluated and tested by using an open framework testing instances

Biometrics system reliability evaluation method

Biometrijski sustavi ulaze u sve češću i rašireniju uporabu od 2003. godine, kada naputak o primjeni istih, u domeni uporabe u svrhu jačanja nacionalne sigurnosti, biva ugrađen u strategiju nacionalne sigurnosti EU, SAD te mnogih drugih zemalja. Motivi za primjenu biometrijskih sustava, posebno u domeni mjera nacionalne sigurnosti, često otvaraju niz pitanja iz područja povjerenja u svrhu korištenja prikupljenih podataka čime se u mnogim situacijama zadire u sferu potencijalnog kompromitiranja i narušavanja privatnosti osoba. Procesi standardizacije biometrijskih antropometrijskih sustava, kao preduvjet za povećanje povjerenja korisnika sustava, aktualni posljednjih godina, uglavnom se fokusiraju na definiranje određenih tehničkih značajki sustava bez eksplicitnog definiranja zahtjeva kvalitete funkcioniranja samih biometrijskih sustava. Pouzdanost biometrijskih sustava jedan je od temeljnih parametara za ocjenu kvalitete istih te sukladno tomu prijedlog budućeg znanstvenog istraživanja biti će utemeljen na povezivanju postojećih saznanja glede evaluacije pouzdanosti biometrijskih sustava s aspekta tehnologije sustava, okoline uporabe te korisnika sustava s ciljem definiranja metode za evaluaciju pouzdanosti utemeljenoj na ontologiji. U radu je dan pregled postojećih modela evaluacije pouzdanosti te razvijen evaluacijski model OOEPBS (otvoreni okvir za evaluaciju pouzdanosti biometrijskih sustava) utemeljen na definiranoj metodi za evaluaciju pouzdanosti biometrijskih sustava. Na temelju evaluacijskog modela OOEPBS izgrađena je ontologija čija je krovna domena biometrijska znanost sa specijalizacijom koncepata koji pokrivaju problematike evaluacije pouzdanosti biometrijskih sustava. Realizirana je također i provjera valjanosti te vrednovanje izgrađene ontologije, te su kreirane i instance koje su poslužile za testiranje okvira.The widespread usage of biometric systems is gaining momentum after 2003., when their utilization, within enforcement national security process, has been ordered and built into security strategies of the E.U., U.S.A., and many other countries. The motives for the utilization of such systems with emphasis on preserving national security, often raises a number of questions in the domain of privacy concerns regarding the potential misuse of the collected data, thus often penetrating into the sphere of potential compromising of users privacy. On the other hand, biometric system's standardization processes, which should be a prerequisite for increasing the users' confidence into the systems, predominantly focuses on defining certain technical features, without explicitly defining quality requirements. Reliability of biometric system is one of the fundamental parameters for evaluating the quality of the same, followed by the proposal of future scientific research will be based on linking existing knowledge regarding the evaluation of the reliability of biometric systems in terms, customer motivation, motivation of use of technology, the environment, usability and performance evaluation parameters with the aim of defining method for evaluating reliability based on ontology. An overview of actual evaluation models is presented in this doctoral thesis and also is developed an evaluation model OOEPBS (open framework for reliability evaluation for biometric systems) based on the reliability evaluation method for biometric systems. OOEPBS evaluation model has served for the development of the ontology with domain in biometrical science and specialization of the concepts within the reliability evaluation area. Ontology is evaluated and tested by using an open framework testing instances