Software reliability prediction using SPN

Reliability is an important software quality parameter. In this research for computation of software reliability, component reliability model based on SPN would be proposed. An isomorphic markov chain is obtained from component SPN model. A quantitative reliability prediction method is proposed. The component reliability value is calculated according to the transition cumulative probability distribution of markov chain, obtained from the software SPN model. By means of reliability prediction of the whole software, we'll introduce CRMPN. In CRMPN states are component reliability model and transition are marked with components reliability. With this research more complex software could be simplified and reliability of the software could be evaluated effectively. An example is provided for demonstrating the feasibility and applicability of our method.Keywords: Reliability, SPN, Markov Chain, Component based-softwar

PSO for multi-objective problems: Criteria for leader selection and uniformity distribution

This paper proposes a method to solve multi-objective problems using improved Particle Swarm Optimization. We propose leader particles which guide other particles inside the problem domain. Two techniques are suggested for selection and deletion of such particles to improve the optimal solutions. The first one is based on the mean of the m optimal particles and the second one is based on appointing a leader particle for any n founded particles. We used an intensity criterion to delete the particles in both techniques. The proposed techniques were evaluated based on three standard tests in multi-objective evolutionary optimization problems. The evaluation criterion in this paper is the number of particles in the optimal-Pareto set, error, and uniformity. The results show that the proposed method searches more number of optimal particles with higher intensity and less error in comparison with basic MOPSO and SIGMA and CMPSO and NSGA-II and microGA and PAES and can be used as proper techniques to solve multi-objective optimization problems

Formal approach on modeling and predicting of software system security: Stochastic petri net

To evaluate and predict component-based software security, a two-dimensional model of software security is proposed by Stochastic Petri Net in this paper. In this approach, the software security is modeled by graphical presentation ability of Petri nets, and the quantitative prediction is provided by the evaluation capability of Stochastic Petri Net and the computing power of Markov chain. Each vulnerable component is modeled by Stochastic Petri net and two parameters, Successfully Attack Probability (SAP) and Vulnerability Volume of each component to another component. The second parameter, as a second dimension of security evaluation, is a metric that is added to modeling to improve the accuracy of the result of system security prediction. An isomorphic Markov chain is obtained from a corresponding SPN model. The security prediction is calculated based on the probability distribution of the MC in the steady state. To identify and trace back to the critical points of system security, a sensitive analysis method is applied by derivation of the security prediction equation. It provides the possibility to investigate and compare different solutions with the target system in the designing phase

Transforming polymorphic process model to petri net: a formal way for validating workflow-based web service composition

Workflow-based web service composition (WB-WSC) is one of the four main categories of web service composition approaches. This category lacks supporting quality of services (QoS). Polymorphic Process Model (PPM) is a WB-WSC that supports both reference process and service-based multi-enterprises processes. Through this paper an initial work was proposed in which PPM was transformed lo Petri Net. Also the final Petri Net model was evaluated structurally. It was also shown that how Petri Net can help to calculate the quality of service in a WB-WSC approach

Mapping Sequence diagram in Fuzzy UML to Fuzzy Petri Net

This ability in fuzzy UML, practically leaves the customers and market’s need without response in this important and vital area. Here, the available sequence diagrams in fuzzy UML will map into fuzzy Petri net. However, the formal models ability will be added to the Semi-formal fuzzy UML. This formalization will add the automatic processing ability to the Semi-formal fuzzy UML. Further more, the other advantages of this mapping is: access to non-functional parameters such as reliability automatically to the considering systems, study the verification of the designed plan and also decrease the expenses because of satiety to make lab sample before its implementation. Using the fuzzy UML mapping into fuzzy Petri net in control, critical and real-time systems will be more applicable