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Here, we work on the problem of point estimation of the parameters of the Poisson-exponential distribution through the Bayesian and maximum likelihood methods based on complete samples. The point Bayes estimates under the symmetric squared error loss (SEL) function are approximated using three methods, namely the Tierney Kadane approximation method, the importance sampling method and the Metropolis-Hastings within Gibbs algorithm. The interval estimators are also obtained. The performance of the point and interval estimators are compared with each other by means of a Monte Carlo simulation. Several conclusions are given at the end.

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Following the increasing growth of urbanization in recent decades in Iran, housing has become one of the most critical issues in the country. In this regard, mass production of housing has received more attention, and residential complexes can be considered a physical manifestation of the idea of mass housing in cities. Operational efficiency in residential construction production systems is evaluated based on average house completion time, the number of houses under construction, and processing time of activities. However, these systems are prone to non-uniformity problems and suspensions resulting from different variables, such as adverse weather conditions, workplace accidents, fluctuations in house demand, and rework. The purpose of this research is to show the effect of reprocessing on the manufacturing process.  In this study, the rework parameter and the variables of frequency, duration, and time of call-back have been considered. Also, the effects of these parameters on tangible performance criteria have been investigated. In this regard, we apply the combined approach of discrete-event simulation and computational modeling; then, we compare the results. Measurements show that the systems fragmented by repeated and short repetitions while referring to early are in optimal performance.

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Abstract
Urban land allocation, planning and management are a complicate problem challenging the decision makers and policy writers all around the Word. The multi objectivity nature of the problem has engaged researchers to deal with the environmental, ecological, economical, social, recreational, commercial, and residential problems simultaneously, in any region, for better decision making. These modelers neglected to consider people’s satisfaction and wellbeing due to land allocation, planning, and development. Complex problems as such as land allocation and planning are in need of suitable integrated model building for solution and analysis. It was to this end that this author proposes a system dynamics approach for studying the impacts of the decisions made, by the policy makers in the long run, on the community’ satisfaction using computer simulation. Taking one land allocation decision into consideration, the results of our proposed dynamic modeling points to this reality that people’s level of satisfaction improves, their level of incomes enhance, and the quality of their lives increases with the passage of time.
 

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Abstract
Objective: From economic, environmental and social perspectives, the sustainability of the supply chain can give a competitive advantage to organizations. By designing a hybrid discrete event agent-based simulation model based on the simulation-optimization approach and meta-heuristic algorithms, this study has sought to evaluate the sustainability of the supply chain and improve the economic, environmental and social objectives of the supply chain.
Method: First, by identifying supply chain agents, an agent-based simulation model is developed. After designing the hybrid simulation model, the verification and validation phases are performed. By combining the simulation model with meta-heuristic algorithms and using the simulation-optimization approach, the optimal/near-optimal values of the components affecting the sustainability of the supply chain are finally extracted.
Findings: In addition to being able to reflect all the complexities of supply chains, the hybrid simulation optimization approach can also improve the key components affecting the sustainability of the supply chain.
Results: Implementation of sustainable supply chain components without optimizing the key variables of the supply chain can lead to the deterioration of performance and sustainability of the supply chain. The components of the maximum levels of product and inventory maintenance and how to implement environmental and social aspects in all the elements of the supply chain have a direct effect on the chain performance and should have appropriate values in different scenarios.
 

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The biggest issue facing both industrialized and emerging nations these days is traffic congestion, which has changed people's perspectives on public transportation systems and accelerated efforts to make them more efficient. Urban traffic issues are a result of various factors, including population growth and the rise in private vehicle ownership. Urban public transportation is currently one of the primary strategies for reducing urban traffic congestion. Building simulation models allows for a more precise analysis of the basic capacity of buses at transfer stations on a given route, trip frequency, passenger behavior, and waiting times. This study suggests using a digital twin design to plan bus routes, reduce wait times for passengers, maximize bus frequency, and investigate the relationship between overall traffic flow and passengers. The Anylogic package program was utilized, which is a helpful tool for digital twin modeling and multi-method simulation. The usefulness of the digital twin concept—which links the physical and virtual worlds—was highlighted in determining the ideal number of trips and trip intervals as a result of the examinations made with the model's outputs. This allows for the instantaneous monitoring and storing of data in its physical conditions.