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Article

Nithya R.P. and Haridass M.

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.

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Kybernetes, vol. 50 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

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Article

Xiaoxiao Fu and Xinran Lehto

The purpose of this study is to provide a nuanced understanding of Chinese family tourists’ value co-creation by examining three important aspects of family vacation: What…

Abstract

Purpose

The purpose of this study is to provide a nuanced understanding of Chinese family tourists’ value co-creation by examining three important aspects of family vacation: What do families do during vacation? How do they make meaning of what they do? Do travelers’ role identities within their families play a role in the value creation process?

Design/methodology/approach

Upon reviewing related theoretical work, the authors undertook a mixed-method study consisting of both survey data and in-depth interviews.

Findings

The analysis revealed three clusters of family interactional content, including We open and share our worlds, We build knowledge and skills and We co-create and co-evaluate, and five clusters of family travelers, including Outdoor enthusiasts, Socializers, Nature lovers, Culture admirers and Relaxation seekers. Family roles, life situations and destination environments also interfaced with family activity participation and family conversations. A family vacation value co-creation process framework with four propositions was, thus, proposed.

Research limitations/implications

Further exploration and validation of the proposed framework and propositions which emerged from the findings of this study are needed. Impacts of various family types and relational dynamics also warrant future investigation.

Practical implications

The results of family interactional and relational well-being facilitated by family vacation are pertinent to academia, industry and public policy-making.

Social implications

Family vacation can be a positive intervention for the creation of family value and a means of meaning-making. Programs that integrate multiple family roles and address family-level value propositions would be collectively enriching.

Originality/value

The current study initiated a pioneering investigation by providing a depiction of how family travelers experience and make sense of a shared tourism experience, along with their value perceptions in such a co-created consumptive scenario.

Details

International Journal of Contemporary Hospitality Management, vol. 30 no. 2
Type: Research Article
ISSN: 0959-6119

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Article

Sarada Yedida and Shenbagam R.

Technological advancements and growing complexity of many real-time systems, namely, communication, transportation, defense systems, etc., necessitate the importance to…

Abstract

Purpose

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.

Design/methodology/approach

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

Findings

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.

Originality/value

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.

Details

International Journal of Quality & Reliability Management, vol. 35 no. 1
Type: Research Article
ISSN: 0265-671X

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Article

Wenfeng Wu, Jianshe Song, Kexia Jiang and Hao Li

This paper aims to study the maintenance and replacement problem for a deteriorating repairable system with multiple vacations of one repairman. It proposes a new…

Abstract

Purpose

This paper aims to study the maintenance and replacement problem for a deteriorating repairable system with multiple vacations of one repairman. It proposes a new replacement policy and establishes corresponding replacement models.

Design/methodology/approach

It is assumed that the repair after the system failures is not “as good as new” and the repairman is in multiple vacations. The reaching of the effective age of the system is assumed to be mutually stochastic at working state, waiting state for repair and being repaired state. Under these assumptions, a replacement policy based on the effective age of the system is applied. The long-run expected downtime per unit time and the long-run expected profit per unit time as objective functions are chosen, respectively. By using geometric process theory and renewal process theory, the mathematic models have been established and the explicit expressions of the long-run expected downtime per unit time and the long-run expected profit per unit time are derived, respectively.

Findings

The optimal replacement policy can be calculated and determined by the computer to minimize the expected downtime or maximize the expected profit. The minimum expected downtime per unit time and maximum expected profit per unit time can also be determined.

Originality/value

This replacement policy and mathematic models can be used as reference to the failure system maintenance and replacement.

Details

Journal of Quality in Maintenance Engineering, vol. just-accepted no. just-accepted
Type: Research Article
ISSN: 1355-2511

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Article

Sherif I. Ammar, Tao Jiang and Qingqing Ye

This paper aims to consider a single server queue with system disasters and impatience behavior are evident in our daily life. For this purpose, authors require to know…

Abstract

Purpose

This paper aims to consider a single server queue with system disasters and impatience behavior are evident in our daily life. For this purpose, authors require to know the general behavior of these systems. Transient analysis shows for us how the system will operate up to some time instant t.

Design/methodology/approach

In this paper, authors consider a single server queue with system disaster and impatient behavior of customers in a multi-phase random environment, in which the system transits to a repair state after each system disaster. When the system is in a failure phase or going through a repair phase, the new arrivals would be impatient. In case the system is not repaired before the customer’s time expires, the customer would leave the queue and never return. Moreover, after repair, the system becomes ready for service in an operative phase with probability $q_{i} \ge 0.$. Using generating functions along with continued fractions and some properties of the confluent hypergeometric function, authors obtained on their own results.

Findings

Explicit expressions have been obtained for the time-dependent probabilities of the underlying queuing model. Also, time-dependent mean and variance of customers in the system are deduced.

Research limitations/implications

The system authors are dealing with is somewhat complicated, there are some performance measures that cannot be achieved, but some of them have been obtained, such as the expectation and variance of the number of customers in the system.

Practical implications

Based on the obtained results, some numerical examples are some numerical examples are presented to illustrate the effect of various parameters on the behavior of the proposed system.

Social implications

Authors’ studied transient analysis of a single server queue with system disaster and impatient customer system is suitable for behavior interpretation of many systems in our lives, such as telecommunication networks, inventory systems and impatient telephone switchboard customers, manufacturing system and service system.

Originality/value

To the best of the author’s/authors’ knowledge and according to the literature survey, in a multi-phase random environment, no previous published article is presented for transient analysis of a single server queue with system disaster and impatient customer behavior in a random environment.

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Article

Chandra Shekhar, Madhu Jain, Ather Aziz Raina and Javid Iqbal

The purpose of this paper is to study the performance metrics of redundant repairable machining system which is applicable in various systems like computer and…

Abstract

Purpose

The purpose of this paper is to study the performance metrics of redundant repairable machining system which is applicable in various systems like computer and communication system, manufacturing and production system, etc.

Design/methodology/approach

In the present investigation, the authors develop Markov model for the system consisting of identical active operating machines which are prone to breakdown. The operating machines are under the care of one permanent repair facility that provides time-sharing basis repair services. The maintenance is facilitated with the provision of standby machines of mixed type and permanent as well as additional repair facility. From the economic point of view, F-policy and N-policy to control the service and arrival of failed machines effectively are included.

Findings

For the performance analysis of the system in long run, the authors compute steady-state probabilities using product-type solution method recursively. Sensitivity analysis is performed numerically for various parameters by developing code in MATLAB.

Social implications

The performance prediction done may be helpful for the system designers and decision makers for the improvement of the existing machining systems in various industries.

Originality/value

Markovian model for the performance prediction of fault tolerant multi-identical operating and standby machines redundant system is developed in generic frameworks by incorporating many noble features which were not all taken together by other researchers working on the same lines. The key concepts incorporated for the modeling of the concerned system is: F-policy, N-policy, time-sharing, and sensitivity analysis of availability and cost function.

Details

International Journal of Quality & Reliability Management, vol. 34 no. 6
Type: Research Article
ISSN: 0265-671X

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Book part

Matthew P. Eddy

A growing number of human rights NGOs have placed international volunteers in conflict zones from Guatemala and Colombia to Palestine and Iraq. This study samples from…

Abstract

A growing number of human rights NGOs have placed international volunteers in conflict zones from Guatemala and Colombia to Palestine and Iraq. This study samples from contemporary high-risk transnational activists and highlights the variation in biographical steps taken toward the shared outcome of participation in human rights work (HRW). Data was collected through 6 weeks of participant observation in Israel-Palestine, 21 in-depth interviews, and 28 shorter focused interviews with human rights workers (N=49). Oversampling from the International Solidarity Movement reveals how the unique constraints and opportunities presented by a particular conflict zone and NGO culture impacts self-selection into HRW. Grounded theory and Boolean methodology aided in identifying four main pathways (the nonviolent activist, peace church, anarchist, and solidarity pathways) to HRW as well as biographical patterns and complexities that have been underemphasized in the existing literature. These include the salience of transformative events and attitude changes in the process of constructing a cosmopolitan identity and committing to high-risk transnational activism.

Details

Research in Social Movements, Conflicts and Change
Type: Book
ISBN: 978-0-85724-609-7

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Book part

Dan E. Houser

Drilling rig work is dangerous, repetitive, and both physically and emotionally taxing, but is attractive to many workers because it affords a means whereby those lacking…

Abstract

Drilling rig work is dangerous, repetitive, and both physically and emotionally taxing, but is attractive to many workers because it affords a means whereby those lacking postsecondary education are able to earn high salaries while still in their twenties and thirties. This chapter examines the workplace culture of the personnel at a number of rig sites in Alberta, Canada. It focuses on the ways in which workers speak about their own motivations and goals and discusses the verbal norms surrounding safety and accidents. It concludes that – the insistence on “money” as the prime motivator in the workers' folk model notwithstanding – there are significant personal rewards inherent in being an accepted member of the production team.

Details

Economic Action in Theory and Practice: Anthropological Investigations
Type: Book
ISBN: 978-0-85724-118-4

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Article

Shao Xiao, Zhixiang Chen and Bhaba R. Sarker

Equipment reliability significantly impacts productivity, and in order to obtain high equipment reliability and productivity, maintenance and production decision should be…

Abstract

Purpose

Equipment reliability significantly impacts productivity, and in order to obtain high equipment reliability and productivity, maintenance and production decision should be made simultaneously to keep manufacturing system healthy. The purpose of this paper is to investigate the joint optimization of equipment maintenance and production decision for k-out-of-n system equipment with attenuation of product quality and to explore the impact of maintenance on the production and cost control for manufacturers.

Design/methodology/approach

A multi-period Markov chain model for k-out-of-n system equipment is set up based on the assumption that the deterioration of equipment is a pure birth process. Then, the maintenance cost, setup cost, inventory holding cost, shortage cost, production cost and the quality cost are analyzed with the uncertain demand and the attenuation of product quality stemmed from equipment deterioration. The total lowest cost per unit time and its specific calculation method are presented. Finally, the robustness and flexibility of the method are verified by a numerical example and the effects of equipment deterioration intensity and attenuation of product quality are analyzed.

Findings

The result shows that the joint decision model could not only satisfy the uncertain demand with low cost and strong robustness but also make the output products high quality level. In addition, the attenuation of product quality would influence the equipment maintenance and production decision and leads to the production waste and increases the operation cost greatly.

Originality/value

Implications derived from this study can help production maintenance managers and reliability engineers adequately select maintenance policy to improve the equipment efficiency and productivity with high quality level at a relatively low cost.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 5
Type: Research Article
ISSN: 0265-671X

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Article

Yossi Hadad and Baruch Keren

The purpose of this paper is to propose a method to determine the optimal number of operators to be assigned to a given number of machines, as well as the number of…

Abstract

Purpose

The purpose of this paper is to propose a method to determine the optimal number of operators to be assigned to a given number of machines, as well as the number of machines that will be run by each operator (a numerical partition). This determination should be made with the objective of minimizing production costs or maximizing profits.

Design/methodology/approach

The method calculates the machines interference rate via the binomial distribution function. The optimal assignment is calculated by transformation of a partition problem into a problem of finding the shortest path on a directed acyclic graph.

Findings

The method enables the authors to calculate the adjusted cycle time, the workload of the operators, and the utility of the machines, as well as the production yield, the total cost per unit, and the hourly profit for each potential assignment of operators to machines. In a case study, the deviation of the output per hour of the proposed method from the actual value was about 2 percent.

Practical implications

The paper provides formulas and tables that give machine interference rates through the application of binomial distribution. The practicability of the proposed method is demonstrated by a real-life case study.

Originality/value

The method can be applied in a wide variety of manufacturing systems that use many identical machines. This includes tire presses in tire manufacturing operations, ovens in pastry manufacturing systems, textile machines, and so on.

Details

International Journal of Productivity and Performance Management, vol. 65 no. 2
Type: Research Article
ISSN: 1741-0401

Keywords

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