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Article Citation - WoS: 10Citation - Scopus: 13Predicting Reliability of Software in Industrial Systems Using a Petri Net Based Approach: a Case Study on a Safety System Used in Nuclear Power Plant(Elsevier, 2022) Kumar, Kuldeep; Sumit; Kumar, Sandeep; Singh, Lalit Kumar; Mishra, AlokContext: Software reliability prediction in the early stages of development can be propitious in many ways. The combinatorial models used to predict reliability using architectures such as fault trees, binary decision diagrams, etc. have limitations in modeling complex system behavior. On the other hand, state-based models such as Markov chains suffer from the state-space explosion problem, and they need transition probability among different system states to measure reliability. These probabilities are usually assumed or are obtained from the operational profile for which the system should be used in the field. Objective: The objective of this paper is to present a method for predicting the reliability of software in industrial systems using a generalized stochastic Petri nets based approach. The key idea is to violate the assumption of state transition probabilities in the Markov chain. The state transition probabilities are calculated using Petri net transitions' throughput by performing stationary analysis under the consideration to identify and handle dead markings in the Petri net. Method: Initially, a generalized stochastic Petri net of the system under consideration is generated from the standard system's specification. Thereafter, dead markings are identified in the Petri net which are further removed to perform steady-state analysis. At last, a Markov model is generated based on the reachability graph of the Petri net, which is further used to predict the system reliability. Results: The presented method has been applied to a safety-critical system, Shut Down System-1, of a nuclear power plant, which is operational in the Canada Deuterium Uranium reactor. The predicted reliability of the system using this method is 99.99966% which has been validated using the specified system requirements. To further validate and generalize the results, sensitivity analysis is performed by varying different system parameters. Conclusions: The method discussed in this paper presents a step of performing structural analysis on the Petri net of the system under consideration to identify and handle dead markings on the Petri net. It further handles the issue of assuming transition probabilities among the system states by calculating them using Petri net transitions' throughput.Article Citation - WoS: 42Citation - Scopus: 60Impact of Physical Ambiance on Communication, Collaboration and Coordination in Agile Software Development: an Empirical Evaluation(Elsevier, 2012) Mishra, Deepti; Mishra, Alok; Ostrovska, SofiyaContext: Communication, collaboration and coordination are key enablers of software development and even more so in agile methods. The physical environment of the workspace plays a significant role in effective communication, collaboration, and coordination among people while developing software. Objective: In this paper, we have studied and further evaluated empirically the effect of different constituents of physical environment on communication, coordination, and collaboration, respectively. The study aims to provide a guideline for prospective agile software developers. Method: A survey was conducted among software developers at a software development organization. To collect data, a survey was carried out along with observations, and interviews. Results: It has been found that half cubicles are 'very effective' for the frequency of communication. Further, half cubicles were discovered 'effective' but not 'very effective' for the quality/effectiveness of communication. It is found that half-height cubicles and status boards are 'very effective' for the coordination among team members according to the survey. Communal/discussion space is found to be 'effective' but not 'very effective' for coordination among team members. Our analysis also reveals that half-height glass barriers are 'very effective' during the individuals problem-solving activities while working together as a team. Infact, such a physically open environment appears to improve communication, coordination, and collaboration. Conclusion: According to this study, an open working environment with only half-height glass barriers and communal space plays a major role in communication among team members. The presence of status boards significantly help in reducing unnecessary communication by providing the required information to individuals and therefore, in turn reduce distractions a team member may confront in their absence. As communication plays a significant role in improving coordination and collaboration, it is not surprising to find the effect of open working environment and status boards in improving coordination and collaboration. An open working environment increases the awareness among software developers e.g. who is doing what, what is on the agenda, what is taking place, etc. That in turn, improves coordination among them. A communal/discussion space helps in collaboration immensely. (C) 2012 Elsevier B.V. All rights reserved.Editorial Information Systems in Distributed Environment(Elsevier, 2016) Mishra, Alok; Munch, Jurgen; Lassenius, Casper; Mishra, Deepti[No Abstract Available]Review Citation - WoS: 70Citation - Scopus: 111Devops and Software Quality: a Systematic Mapping(Elsevier, 2020) Mishra, Alok; Otaiwi, ZiadoonQuality pressure is one of the factors affecting processes for software development in its various stages. DevOps is one of the proposed solutions to such pressure. The primary focus of DevOps is to increase the deployment speed, frequency and quality. DevOps is a mixture of different developments and operations to its multitudinous ramifications in software development industries, DevOps have attracted the interest of many researchers. There are considerable literature surveys on this critical innovation in software development, yet, little attention has been given to DevOps impact on software quality. This research is aimed at analyzing the implications of DevOps features on software quality. DevOps can also be referred to a change in organization cultures aimed at removal of gaps between the development and operations of an organization. The adoption of DevOps in an organization provides many benefits including quality but also brings challenges to an organization. This study presents systematic mapping of the impact of DevOps on software quality. The results of this study provide a better understanding of DevOps on software quality for both professionals and researchers working in this area. The study shows research was mainly focused in automation, culture, continuous delivery, fast feedback of DevOps. There is need of further research in many areas of DevOps (for instance: measurement, development of metrics of different stages to assess its performance, culture, practices toward ensuring quality assurance, and quality factors such as usability, efficiency, software maintainability and portability). (C) 2020 The Author(s). Published by Elsevier Inc.Article Citation - WoS: 25Citation - Scopus: 31Knowledge management in requirement elicitation: Situational methods view(Elsevier, 2018) Mishra, Deepti; Aydin, Secil; Mishra, Alok; Ostrovska, SofiyaIn small-scale software development organizations, software engineers are beginning to realize the significance of adapting software development methods according to project conditions. There is a requirement to proliferate this know-how to other developers, who may be facing the same settings/context, so that they too can benefit from others' experiences. In this paper, the application of situational method engineering in requirements elicitation phase is investigated. A novel, simple and dynamic web-based tool, Situational Requirement Method System (SRMS), is developed which can aid in conception/formulation, repository, and elicitation/derivation of methods related with this stage. The proposed approach and tool are validated by distributing a questionnaire among software professionals working in large software companies, and making SRMS accessible to them. The results indicate that a majority of the participants finds SRMS useful and provides various suggestions to improve it. (c) 2017 Elsevier B.V. All rights reserved.
