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The purpose of this paper is to provide simulation modelling for bulk arrival bulk service queueing system involved in a textile industry and analyze the performance metrics.

This paper describes the simulation modelling of a bulk queueing system with limited number of admissions and multiple vacations. The model is developed for the proposed queueing system using Flexsim 2017, and it is explained through an application observed in a textile industry involving the process of cone winding.

In this paper, the simulation model has been developed to study the behaviour of queues at different resources in a production system. Various performance measures such as average components, average waiting time, total number of inputs and outputs, processing time and idle time involved in a textile industry are evaluated using simulation and justified through numerical illustration.

The proposed simulation model may be used in various scenarios wherever a real time situation exists related to bulk queueing system. The results produced in this paper can be used by the manufacturing industries to enhance the need-based accuracy. It is worth pointing out that the findings are of direct practical relevance and can be successfully used for a number of industrial applications.

The approach suggested in this paper attempts to deal with the queueing system involved in a textile industry and provides numerical results in less time with less computer resources. It provides a reasonably good approximation for simple and complex queueing models where it is difficult to find closed form of theoretical results.

Discusses “recurrent approaches” to determining when to despatch a consolidated load. Unlike a “non‐recurrent approach” (which sets a target time or weight prior to accumulating orders and despatches when the target is reached), recurrent approaches re‐evaluate the shipment‐release decision several times within an order accumulation cycle. Presents two probabilistic recurrent models, one assuming private transportation and the other common carriage. Compares the performance of these models with the nonrecurrent rules of despatching the “economic shipment weight” or, in the case of common carriage, the minimum volume weight. Concludes that with both forms of transportation, the decision heuristic outperforms despatching the economic shipment weight when that weight is close to vehicle capacity. Shows that, with common carriage, the use of the more sophisticated model does not yield better cost results than the minimum volume weight despatch rule. Discusses the reasons for, and implications of, these results.

The purpose of this paper is to propose a stochastic optimisation model for integrating service and maintenance policies in order to solve the queuing problem and the cost of maintenance activities for public transport services, with a particular focus on urban ropeway system.

The authors adopt the following approaches: a discrete-event model that uses a set of interrelated queues for the formulation of the service problem using a cost-based expression; and a maintenance model consisting of preventive and corrective maintenance actions, which considers two different maintenance policies (periodic block-type and age-based).

The work shows that neither periodic block-type maintenance nor an age-based maintenance is necessarily the best maintenance strategy over a long system lifecycle; the optimal strategy must consider both policies.

The maintenance policies are then evaluated for their impact on the service and operation of the transport system. The authors conclude by applying the proposed optimisation model using an example concerning ropeway systems.

This is the first study to simultaneously consider maintenance policy and operational policy in an urban aerial ropeway system, taking up the problem of queuing with particular attention to the unique requirements public transport services.

Technological advancements and growing complexity of many real-time systems, namely, communication, transportation, defense systems, etc., necessitate the importance to adopt a well-planned repair process such as phase type quasi-renewal process contributing to an improved system performance. Further, in an attempt to boost the role of maintenance as a financial benefactor, repairman’s multiple vacation policy is incorporated. Also, the significance of the degree of repair is illustrated while indicating the suitability of the matrix-analytic approach via the phase type quasi-renewal operating/repair times in reliability. The paper aims to discuss these issues.

The optimal replacement policy is obtained by employing the matrix-analytic method and minimum average cost rate.

The considered models make a significant contribution towards establishing that the matrix-analytic method, using the phase type quasi-renewal process, aids in reducing the computations and also fills the gap in the literature in the study of deteriorating systems. Availability and rate of occurrence of failures are evaluated in transient and steady-state regime.

This model differs from the existing models, in that, a repairman’s multiple vacation, delayed repair time and representation of the failure occurrence by a mixed Poisson process have been incorporated into the analysis. Also, time-dependent case and N-policy have been adopted to explore the optimality issues using phase type quasi-renewal process analytically. The numerical illustrations warrant that the maintenance policy proposed in this paper produces a considerably lower cost.

The purpose of the paper is to analyze reliability characteristics of batch service queuing system with a single server model that envisages Poisson input process and exponential service times under first come, first served (FCFS) queue discipline.

With the help of renewal theory and stochastic processes, a model has been designed to discuss the reliability and its characteristics.

The instantaneous and steady-state availability along with the maintenance model of the systems subject to generalized M/M_b/1 queuing model is derived, and a few particular cases for availability are obtained as well. For supporting the developed model, a case study on electrical distribution system (EDS) has been illustrated, which also includes a comparison for the system subject to M/Mb/1 queuing model and the system without any queue (delay).

It is a quite realistic model that may aid to remove congestion in the system while repairing.

The purpose of this paper is to examine practices, realities and opportunities relevant to Moroccan tourism. In the process, the competitiveness of this vital economic sector is assessed. Based on this examination, relevant, benchmarking implications are identified and advanced to policy makers.

The shift‐share technique is utilized to analyze tourist arrivals, from different regions of the world, to Morocco, Turkey, Tunisia and Egypt. The shift‐share analysis is utilized to understand the existing competitive position of Morocco in relation to her main competitors.

The results of the shift‐share analysis revealed that Morocco has not performed as well as the rest of the competitors in the benchmark group. This was attributed, in part, to focusing on markets with less potential for growth.

The shift‐share technique utilized in this study is a diagnostic tool. Thus, more research is needed to uncover the dynamic relationships relevant to the competitive position of Moroccan tourism.

The findings of this study have clear benchmarking implications to Moroccan policy makers, as they pursue a more comprehensive and systematic tourism strategy.

The applied research presented in this article is consistent with the increasing significance of global tourism.

The purpose of this paper is to study determining factors of international tourism demand in Middle Eastern countries.

Panel data pattern is used for data analysis of 1995 to 2013.

Results indicate variables like trade freedom index and gross domestic product (GDP) have positive and significant impact upon tourism demand of the countries of the region. Purchasing power parity (PPP) and GDP per capita are indicators which affect the tourism demand rate in Middle East negatively.

It is estimated that Middle East region will claim for the bulk of tourist arrivals in following years. Therefore, this study is vital for destination managers to plan for demand in future.

The purpose of this paper is to carry out queuing analysis to analyse patient load in outpatient and inpatient services to facilitate more realistic resource planning.

The paper adopts an analytical approach based on real life data (e.g. not a priori or an academic one where data are mingled to fit a theoretical stance) in accordance with the service level prescribed by the hospital administration. A service level is usually specified in terms of admissible range of queuing characteristics, such as mean patient waiting time, reduction of inordinate delays, incidences of minimum delays, average queue length, etc. which the management of a health organisation may decide to aim and control.

Queuing analysis reported in this case study provides a basis for estimating medical staff size and number of beds, which are two very important resources for outpatient and inpatient services in a large hospital, and all other hospital resources in one way or another depend on them.

The study challenges and aims to replace thumb‐rule approaches, which can be very conveniently carried out with efficient computer aids available at present for any hospital. Queuing analysis provides valuable insights into a hospital system, though it may not be the best approach as several underlying assumptions may not always hold true. In hospitals, for example, there can be several interacting queues, many of which could be cyclic with interaction among them. Accordingly, treatment of each queue individually, independent of others may not be a valid assumption.

Medical staff (doctors) and beds are very basic hospital resources, which largely depend on the hospital load in terms of arrival rates of patients in outpatient and inpatient services. When hospitals are adequately staffed and equipped in terms of beds and other key resources, it is unlikely that patients will turn away to other hospitals for treatment and there will be all round satisfaction with the hospital performance.

The authors do not claim the findings to be novel or unique but rather more well‐documented and comprehensive in coverage than available in existing literature. The practice‐based themes such as this well‐documented case study may evoke global interest as a multiplier effect for using such methodologies for resource planning in hospitals.

An integrated queueing network focused on container storage/retrieval operations occurring on the yard of a transshipment hub is proposed. The purpose of the network is to support decisions related to the organization of the yard area, while also accounting for operations policies and times on the quay.

A discrete-event simulation model is used to reproduce container handling on both the quay and yard areas, along with the transfer operations between the two. The resulting times, properly estimated by the simulation output, are fed to a simpler queueing network amenable to solution via algorithms based on mean value analysis (MVA) for product-form networks.

Numerical results justify the proposed approach for getting a fast, yet accurate analytical solution that allows carrying out performance evaluation with respect to both organizational policies and operations management on the yard area.

Practically, the expected performance measures on the yard subsystem can be obtained avoiding additional time-expensive simulation experiments on the entire detailed model.

As a major takeaway, deepening the MVA for generally distributed service times has proven to produce reliable estimations on expected values for both user- and system-oriented performance metrics.

The aim of this paper is to contribute to one's understanding of vulnerabilities for abuse in the realm of trade and commerce, and to appreciate how inattention to this issue undermines all other financial controls.

The authors review the US rules and regulations regarding non‐vessel‐operating common carriers and Customs brokers pointing out ways in which the current regulatory framework can be violated.

It was found that the potential for the commission of serious crime through import/export activities is high and requires urgent attention, without which all AML/CFT and anti‐corruption efforts can be rendered ineffective.

More data and analysis of trade transparency and national rules as well as cases highlighting concretely how these are being infringed is indispensable for planning and implementation of trade transparency initiatives.

As trade transparency units or similar projects are likely to emerge, strategic thinking, coordination of efforts and maximization of synergies for improved governance and crime control are imperative. Failure to do so will allow serious misconduct and security risks to remain high.

AML/CFT and anti‐corruption practitioners, donor organizations and technical assistance providers ought to be familiar with the significance of weak capacities to trace and monitor trade transactions and how to connect this issue with wider governance and crime control policies/measures.