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The purpose of this paper is to develop a methodology based on TODIM (an acronym in Portuguese for interactive and multicriteria decision-making) approach for the selection of the best alternative in the context of multi criteria group decision-making (MCGDM) problems under possibilistic uncertainty in interval-valued Pythagorean fuzzy (IVPF) environment.

In this paper, IVPF-TODIM method is proposed. Some new point operator-based similarity measures (POSMs) for IVPF sets (IVPFSs) are introduced which have the capability to reduce the degree of uncertainty of the elements in the universe of discourse corresponding to IVPFS. Then the newly defined POSMs are used to compute the measure of relative dominance of each alternative over other alternatives in the IVPF-TODIM context. Finally, generalized mean aggregation operator is used to find the best alternative.

As the TODIM method is used to solve the MCGDM problems under uncertainty, POSMs are developed by using three parameters which can control the effect of decision-makers’ psychological perception under risk.

The decision values are used in IVPF numbers (IVPFNs) format.

The proposed method is capable to solve real-life MCGDM problems with not only IVPFNs format but also with interval-valued intuitionistic fuzzy numbers.

As per authors’ concern, no approach using TODIM with IVPFNs is found in literature to solve MCGDM problems under uncertainty. The final judgment values of alternatives using the extended TODIM methodology are highly corroborate in compare to the results of existing methods, which proves its great potentiality in solving MCGDM problems under risk.

This paper aims to consider a sustainable inventory model with price dependent demand, non-instantaneous deterioration rate, discount facility, partially backlogged shortages and advance and delay in payments for a two-warehouse system.

This model considered a non-instantaneous deterioration, which starts after a certain period with a constant rate. The deterioration rate in the rented warehouse is more compared to own warehouse. The proposed model focused on two things. The first one is to the benefits of the advance payments strategy and delayed payment for the retailer and supplier, where the two-warehouse system is available and the second one is using an appropriate discount facility on no of the installment to maximize the total profit. The classical optimization technique is used to solve the problem.

The combination of trade-credits and advance payments is initiated to provide more benefits to the retailer. The findings prove that advance payments, which are received from the retailer to the supplier are beneficial for the supplier, who can influence the demand increase because of higher lower selling prices. Decreasing the selling price is used as a catalyst to increase demand. It also extends the discount concept of Khan et al. (2019, 2019b).

This model is limited by the fact that it does not consider variable deterioration. Therefore, the proposed inventory model could be extended by considering variable deterioration, as well as fully backlogged shortages and time-dependent demand function.

The study simultaneously considers a non-instantaneous deterioration inventory model, advance-payment, trade-credit for a sustainable two-warehouse inventory system. From the literature search to the best of knowledge no researcher has undergone this sort of study.

This study aims to attempt to construct a new mathematical model of the generalized thermoelasiticity theory based on the memory-dependent derivative (MDD) considering three-phase-lag effects. The governing equations of the problem associated with kernel function and time delay are illustrated in the form of vector matrix differential equations. Implementing Laplace and Fourier transform tools, the problem is sorted out analytically by an eigenvalue approach method. The inversion of Laplace and Fourier transforms are executed, incorporating series expansion procedures. Displacement component, temperature and stress distributions are obtained numerically and illustrated graphically and compared with the existing literature.

This study is to analyze the influence of MDD of three-phase-lag heat conduction interaction in an isotropic semi-infinite medium. The current model has been connected to generalize two-dimensional (2D) thermoelasticity problem. The governing equations are shown in vector matrix form of differential equation concerning Laplace-transformed domain and solved by using the eigenvalue technique. The combined Laplace Fourier transform is applied to find the analytical interpretations of temperature, stresses, displacement for silicon material in a non-dimensional form. Inverse Laplace transform has been found by applying Fourier series expansion techniques introduced by Honig and Hirdes (1984) after performing the inverse Fourier transform.

The main conclusion of this current study is to demonstrate an innovative generalized concept for heat conducting Fourier’s law associated with moderation of time parameter, time delay variable and kernel function by applying the MDDs. However, an important role is played by the time delay parameter to characterize the behavioral patterns of the physical field variables. Further, a new categorization for materials may be created rendering to this new idea along MDD for the time delay variables to develop a new measure of its potential to regulate heat in the medium.

Generalized thermoelasticity is hastily undergoing modification day-by-day from basic thermoelasticity. It has been progressed to get over from the limitations of fundamental thermoelasticity, for instance, infinite velocity components of thermoelasticity interference, in the adequate thermoelastic response of a solid to short laser pulses and deprived illustrations of thermoelastic performance at low temperature. In the past few decades, the fractional calculus is used to change numerous existing models of physical procedure, and its applications are used in various fields of physics, continuum mechanics, fluid mechanics, biology, viscoelasticity, biophysics, signal and image processing, control theory, engineering fields, etc.

The purpose of this paper is to study the effect of a critical subsystem development indigenously on the outcome of an Indian defence R&D project. Indigenous development of the critical subsystem requires the development of a number of technologies; hence the study is taken up for indigenously development of critical subsystem.

A simulation-based approach is used in this paper for studying the effect of indigenization decisions. A defence R&D project with the critical subsystems is modeled in Graphical Evolution and Review Technique (GERT) networks, and simulated in Arena simulation software using discrete event simulation model. The simulation model is thereafter experimented with decision options for the critical subsystem. Data were collected from the project management office (PMO) of short range homing guided missile (SRHGM) for this simulation study.

It has been found in this case that timely development of technology plays a key role in the Indian defence R&D projects. While indigenization of critical components reduces cost of development, the trade-off lies in much increased project development time. It is imperative that project teams should identify critical components early and work out appropriate strategies of indigenous development to avoid time overrun of the projects.

The accuracy of results of the study could perhaps be affected on account of the extent of data forthcoming from the PMO. However, GERT framework presented in this paper is realistically derived from the practices used in the SRHGM project.

The study would help the project teams to identify critical subsystems early and work out appropriate strategies of indigenous development to avoid time overrun of the projects. This study would also make the project as well as the R&D teams aware of the causes for delays and cost overruns, and assist to deliver a product meeting end-user requirements.

The paper aims to study manpower dynamics at offshore and onsite location for maintenance project, which are transferred to offshore location in a phase-wise manner. The purpose of the paper is to find good values of onsite–offshore team strength, the number of hours of communication between onsite and offshore teams for smooth transfer of software maintenance project to offshore location.

This study uses system dynamics simulation approach to study manpower allocation at onsite and offshore locations to transfer the maintenance work to offshore location in a gradual manner. The authors consulted 13 experts from Indian software outsourcing industry during the model construction and validation.

The simulation results show that the complexity of maintenance project has an insignificant effect on offshore migration. The maintenance work transfer should start with initial onsite team strength higher than that of required for ticket solving and project. The initial offshore team strength should be based on training capacity available at the onsite location. The higher attrition rate at an offshore is detrimental for offshore migration.

The implication of the study is in the development of a broad framework of software maintenance work transfer to offshore locations for Indian software outsourcing projects. As the study is based on expert opinion in the context of India, it cannot be generalized for outsourcing scenarios elsewhere.

The software project manager can use the findings to get more insight into maintenance project offshore migration and divide the software team between onsite and offshore location.

The study is novel as there is little attempt at finding the manpower composition at onsite and offshore locations for software maintenance project during the migration phase.

The purpose of this paper is to evolve a guideline for scientists and development engineers to the failure behavior of electro-optical target tracker system (EOTTS) using fuzzy methodology leading to success of short-range homing guided missile (SRHGM) in which this critical subsystems is exploited.

Technology index (TI) and fuzzy failure mode effect analysis (FMEA) are used to build an integrated framework to facilitate the system technology assessment and failure modes. Failure mode analysis is carried out for the system using data gathered from technical experts involved in design and realization of the EOTTS. In order to circumvent the limitations of the traditional failure mode effects and criticality analysis (FMECA), fuzzy FMCEA is adopted for the prioritization of the risks. FMEA parameters – severity, occurrence and detection are fuzzifed with suitable membership functions. These membership functions are used to define failure modes. Open source linear programming solver is used to solve linear equations.

It is found that EOTTS has the highest TI among the major technologies used in the SRHGM. Fuzzy risk priority numbers (FRPN) for all important failure modes of the EOTTS are calculated and the failure modes are ranked to arrive at important monitoring points during design and development of the weapon system.

This paper integrates the use of TI, fuzzy logic and experts’ database with FMEA toward assisting the scientists and engineers while conducting failure mode and effect analysis to prioritize failures toward taking corrective measure during the design and development of EOTTS.

A vast proportion of global megaprojects have not performed up to the expectations of their stakeholders. A failed megaproject has the potential even to derail the economy of a country where it was implemented. Stakeholders must, therefore, ensure that they do not invest in megaprojects that are bound to fail. But, how can stakeholders consistently identify such megaprojects? This paper develops a framework for a metric that can help stakeholders measure the readiness of a megaproject.

A comprehensive literature review identified 19 critical success factors of megaprojects. These success factors were integrated into a fuzzy-based model to develop the megaproject readiness metric. An assessment team studied the levels of presence and importance of these success factors in a candidate megaproject to derive its readiness.

The readiness-based model provides stakeholders valuable insights into the strong and weak areas of a megaproject. It can help stakeholders prioritize and systematically eliminate the identified weaknesses and improve megaproject readiness. While the model was tested on a metro rail megaproject, it can be used on any megaproject across domains.

This paper adopts the concept of readiness for the domain of megaprojects. Besides the readiness measurement framework, a vital contribution of this research is its application to a real-life case. Future research can include more granular success factors to improve the estimate of megaproject readiness.