Template-Type: ReDIF-Article 1.0 Author-Name: Roshli Aniyeri Author-X-Name-First: Roshli Author-X-Name-Last: Aniyeri Author-Name: Ratnam Nadar Author-X-Name-First: Ratnam Author-X-Name-Last: Nadar Title: Passengers queue analysis in international airports terminals in Kerala using multiphase queuing system Abstract: Waiting period is a global problem that almost everyone has to face, which causes a great waste of time for everyone. It is well known that all these waiting line problems critically restrict further development. The focus of this study is to deal with passengers' queue issues of the international airport terminals of Kerala. Queuing theory is a mathematical approach to the study of waiting period in queues. This study evaluates the effectiveness of multi-server queuing model. The multi server approach of modelling was adopted in this cram to develop a mathematical model to solve problem of queuing of air transport passengers at the international airports in Kerala. The airport in the aviation industry of the country faces problems of many passengers queuing for boarding, departure with different arrival rate due to non availability of state of the art logistics management mechanisms for predicting the nature and service demands of travellers. The passengers' average wait time for reaching the gate area measures system performance. A mathematical queuing model was developed in this study and comparisons are made using analysis of variance (ANOVA). Journal: Int. J. of Mathematics in Operational Research Pages: 1-30 Issue: 1 Volume: 12 Year: 2018 Keywords: multi server queuing modelling; airport passengers; queuing steady state condition; estimated queue length; utilisation factor; analysis of variance; ANOVA. File-URL: http://www.inderscience.com/link.php?id=88566 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:1-30 Template-Type: ReDIF-Article 1.0 Author-Name: S. Morteza Mirdehghan Author-X-Name-First: S. Morteza Author-X-Name-Last: Mirdehghan Author-Name: Maryam Heydari Author-X-Name-First: Maryam Author-X-Name-Last: Heydari Title: Characterisations of the production possibility set in data envelopment analysis: an MOLP approach Abstract: The production possibility set in data envelopment analysis is a polyhedron and it is defined by the intersection of a finite number of half spaces which are constructed by their corresponding defining hyperplanes. Because of the importance of the characterisations of the production possibility sets in data envelopment analysis, we suggest two multi objective linear programming problems and then we identify some characterisations of the production possibility set by investigation of the relations among the suggested multi objective linear programming models and the input oriented envelopment and multiplier BCC models. In this paper, we use weighted sum and epsilon-constraint scalarisation methods to present some mathematical properties for finding some relations among the efficient solutions of the proposed multi objective linear programming models and the characteristics of the production possibility set and data envelopment analysis models. Journal: Int. J. of Mathematics in Operational Research Pages: 31-44 Issue: 1 Volume: 12 Year: 2018 Keywords: data envelopment analysis; multi-objective linear programming; efficient weights. File-URL: http://www.inderscience.com/link.php?id=88567 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:31-44 Template-Type: ReDIF-Article 1.0 Author-Name: Ali Khaleel Dhaiban Author-X-Name-First: Ali Khaleel Author-X-Name-Last: Dhaiban Author-Name: Md. Azizul Baten Author-X-Name-First: Md. Azizul Author-X-Name-Last: Baten Author-Name: Nazrina Aziz Author-X-Name-First: Nazrina Author-X-Name-Last: Aziz Title: An optimal inventory control in hybrid manufacturing/remanufacturing system with deteriorating and defective items Abstract: An optimal control model in a manufacturing/remanufacturing-inventory system, with defective, deteriorating, returned and disposed items was developed. In this model, the time of deterioration, and the percentages of defective, returned and disposed items were assumed random variables that follow the gamma distribution, beta rectangular, four-parameter generalised beta (FPGB) and Kumaraswamy distributions, respectively. The total of returned items from customers and defective items divided into the remanufacturing and disposed items. An optimality conditions were derived from the dynamic of the manufacturing/remanufacturing inventory level. The explicit solution under continuous-review policy was achieved by using the Pontryagin maximum principle. Also, simulation and sensitivity analysis results were illustrated numerically. The numerical results suggested that the model can help firms to maintain a balance between the manufacturing and remanufacturing rates to hedge demand and inventory levels. Also, the manufacturing rate was positively related to the disposal rate. Journal: Int. J. of Mathematics in Operational Research Pages: 66-90 Issue: 1 Volume: 12 Year: 2018 Keywords: optimal control; inventory system; deteriorating items; defective items; Pontryagin maximum principle; demand function. File-URL: http://www.inderscience.com/link.php?id=88575 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:66-90 Template-Type: ReDIF-Article 1.0 Author-Name: Hossein Khanjarpanah Author-X-Name-First: Hossein Author-X-Name-Last: Khanjarpanah Author-Name: Mir Saman Pishvaee Author-X-Name-First: Mir Saman Author-X-Name-Last: Pishvaee Title: A fuzzy robust programming approach to multi-objective portfolio optimisation problem under uncertainty Abstract: Portfolio selection is one of the most important problems in financial markets. This paper proposes a novel robust flexible portfolio optimisation model based on possibilistic mean and variance and flexible constraints, to cope with inherent uncertainty of such problem. The proposed model is extended by introducing a modified robust flexible approach. The developed models are evaluated and validated by using the real data of Tehran stock exchange. The obtained results show that in higher violation penalties, the proposed models outperform the deterministic model. In addition, experimental analyses are provided to compare the performance of the robust flexible portfolio optimisation model to the modified version. Journal: Int. J. of Mathematics in Operational Research Pages: 45-65 Issue: 1 Volume: 12 Year: 2018 Keywords: fuzzy mathematical programming; robust optimisation; portfolio problem; possibilistic mean; possibilistic variance; flexible constraints. File-URL: http://www.inderscience.com/link.php?id=88576 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:45-65 Template-Type: ReDIF-Article 1.0 Author-Name: R. Sebasthi Priya Author-X-Name-First: R. Sebasthi Author-X-Name-Last: Priya Author-Name: R. Sudhesh Author-X-Name-First: R. Author-X-Name-Last: Sudhesh Title: Transient analysis of a discrete-time infinite server queue with system disaster Abstract: This paper studies a discrete-time infinite server queue subject to system disaster. The exact time-dependent probabilities of the number of customers present in the system are obtained using generating functions, continued fractions and confluent hypergeometric functions. Further, the results are extended to obtain closed form expression for busy period distribution and steady state system size probabilities. Numerical illustrations are provided to visualise the effect of system size probabilities, both in steady state and transient state, and busy period distribution for different parameter values. Journal: Int. J. of Mathematics in Operational Research Pages: 91-101 Issue: 1 Volume: 12 Year: 2018 Keywords: discrete queue; time-dependent probability; generating functions; busy period; confluent hypergeometric functions; continued fractions. File-URL: http://www.inderscience.com/link.php?id=88580 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:91-101 Template-Type: ReDIF-Article 1.0 Author-Name: Adarsh Anand Author-X-Name-First: Adarsh Author-X-Name-Last: Anand Author-Name: Mohini Agarwal Author-X-Name-First: Mohini Author-X-Name-Last: Agarwal Author-Name: Deepti Aggrawal Author-X-Name-First: Deepti Author-X-Name-Last: Aggrawal Author-Name: Ompal Singh Author-X-Name-First: Ompal Author-X-Name-Last: Singh Title: Queuing theory-based innovation diffusion modelling incorporating change in adoption rate Abstract: Adoption has always been an important process to discuss among marketers. Major work in the field of innovation adoption has been based on theory of first purchase by consumers. Of late attention has also been given to multi-stage nature of diffusion process. There are practitioners who have verified adoption as multi-stage process (depending on awareness and motivation). Researchers have lately also understood the value of change in marketing strategy and other factors that often lead to change in the rate of adoption. In this paper, we have made use of this stage wise approach of market penetration along with change point concept, have developed a methodical approach based on infinite server queuing theory and predicted sales for consumer durables. Experimental results estimated on sales of two different consumer durables show that present proposal can depict the change in adoption rates and predict the behaviour of the product in more accurate manner. Journal: Int. J. of Mathematics in Operational Research Pages: 102-116 Issue: 1 Volume: 12 Year: 2018 Keywords: change points; CPs; non-homogeneous Poisson process; NHPP; innovation diffusion model; IDM. File-URL: http://www.inderscience.com/link.php?id=88581 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:102-116 Template-Type: ReDIF-Article 1.0 Author-Name: Deepa Khurana Author-X-Name-First: Deepa Author-X-Name-Last: Khurana Author-Name: Shilpy Tayal Author-X-Name-First: Shilpy Author-X-Name-Last: Tayal Author-Name: S.R. Singh Author-X-Name-First: S.R. Author-X-Name-Last: Singh Title: An EPQ model for deteriorating items with variable demand rate and allowable shortages Abstract: The fundamental assumption of an economic order quantity (EOQ) model is that 100% of items in an ordered lot are perfect. This assumption is not always pertinent for production processes because of process deterioration or other factors. This is an economic production quantity model for deteriorating items. To fulfil the market demands and expectations, the production rate is taken as a function of demand rate. The demand and deterioration of the products are time dependent function. Shortages are allowed and partially backlogged. The backlogging phenomenon in the literature is often modelled using backordering and lost sale costs. The backlogging option gets used only when it is economic to do so. The inventory policy proposed here considers the optimal production run time, production quantity and shortage period such that the total average cost can be minimised. Numerical examples are provided to illustrate and sensitivity analyses of optimal solutions are given for the proposed inventory model. Journal: Int. J. of Mathematics in Operational Research Pages: 117-128 Issue: 1 Volume: 12 Year: 2018 Keywords: deterioration; shortages; variable production rate; economical production quantity; EPQ; partial backlogging. File-URL: http://www.inderscience.com/link.php?id=88582 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:117-128 Template-Type: ReDIF-Article 1.0 Author-Name: Manije Sanei Tabass Author-X-Name-First: Manije Sanei Author-X-Name-Last: Tabass Author-Name: G.R. Mohtashami Borzadaran Author-X-Name-First: G.R. Mohtashami Author-X-Name-Last: Borzadaran Title: The generalised maximum α entropy principle Abstract: Generalisations of maximum entropy principle (MEP) and minimum discrimination information principle (MDIP) are described by Kapur and Kesavan (1989) . In this paper, we used generalised entropies and replaced Shannon entropy with Tsallis entropy when α = 2 . The generalisation has been achieved by the entropy maximisation postulate and examining its consequences . The inverse principles which are inherent in the maximum α entropy and minimum discrimination α entropy are made in the new methodology. Journal: Int. J. of Mathematics in Operational Research Pages: 129-137 Issue: 1 Volume: 12 Year: 2018 Keywords: Shannon entropy; Tsallis entropy; Tsallis divergence; generalised maximum entropy principle; GMEP; maximum entropy principle; MEP; minimum discrimination. File-URL: http://www.inderscience.com/link.php?id=88583 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:1:p:129-137 Template-Type: ReDIF-Article 1.0 Author-Name: Abdulqader Othman Hamadameen Author-X-Name-First: Abdulqader Othman Author-X-Name-Last: Hamadameen Author-Name: Nasruddin Hassan Author-X-Name-First: Nasruddin Author-X-Name-Last: Hassan Title: Pareto optimal solution for multiobjective stochastic linear programming problems with partial uncertainty Abstract: A study on multiobjective stochastic linear programming (MSLP) problems with partial information on probability distribution is conducted. A method is proposed to utilise the concept of dominated solution for the multiobjective linear programming (MLP) problems, and find a pareto optimal solution (POS) without converting the MLP problem into its unique linear programming (LP) problem. An algorithm is proposed along with a numerical example which illustrated the practicability of the proposed algorithm. Comparison of results with existing methods shows the efficiency of the proposed method based on the analysis of results performed. Journal: Int. J. of Mathematics in Operational Research Pages: 139-166 Issue: 2 Volume: 12 Year: 2018 Keywords: dominated solution; fuzzy transformation; MSLP problems; pareto optimal solution; POS; stochastic transformation. File-URL: http://www.inderscience.com/link.php?id=89675 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:139-166 Template-Type: ReDIF-Article 1.0 Author-Name: Reza Hassanzadeh Author-X-Name-First: Reza Author-X-Name-Last: Hassanzadeh Author-Name: Iraj Mahdavi Author-X-Name-First: Iraj Author-X-Name-Last: Mahdavi Author-Name: Nezam Mahdavi-Amiri Author-X-Name-First: Nezam Author-X-Name-Last: Mahdavi-Amiri Author-Name: Ali Tajdin Author-X-Name-First: Ali Author-X-Name-Last: Tajdin Title: An α-cut approach for fuzzy product and its use in computing solutions of fully fuzzy linear systems Abstract: We propose an approach for computing the product of various fuzzy numbers using <i>α</i>-cuts. A regression model is used to obtain the membership function of the product. Then, we make use of the approach to compute solutions of fully fuzzy linear systems. We also show how to compute solutions of fully fuzzy linear systems with various fuzzy variables. Examples are worked out to illustrate the approach. Journal: Int. J. of Mathematics in Operational Research Pages: 167-189 Issue: 2 Volume: 12 Year: 2018 Keywords: fuzzy numbers; α-cut; regression model; fuzzy product; fully fuzzy linear system; FFLS. File-URL: http://www.inderscience.com/link.php?id=89676 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:167-189 Template-Type: ReDIF-Article 1.0 Author-Name: Nirbhay Mathur Author-X-Name-First: Nirbhay Author-X-Name-Last: Mathur Author-Name: Pankaj Kumar Srivastava Author-X-Name-First: Pankaj Kumar Author-X-Name-Last: Srivastava Author-Name: Ajit Paul Author-X-Name-First: Ajit Author-X-Name-Last: Paul Title: Algorithms for solving fuzzy transportation problem Abstract: The objective of this paper is a wide survey of recent optimisation techniques in the field of fuzzy transportation problems. The authors have reviewed papers on various techniques to solve fuzzy transportation problems. We have considered the algorithms discussed in research papers within the last decade so as to know the present scenario. A comparative study of methods with own critical comments as remarks has been included. Journal: Int. J. of Mathematics in Operational Research Pages: 190-219 Issue: 2 Volume: 12 Year: 2018 Keywords: fuzzy transportation problem; linear programming method; classical methods; zero point method; zero suffices method; zero termination method. File-URL: http://www.inderscience.com/link.php?id=89677 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:190-219 Template-Type: ReDIF-Article 1.0 Author-Name: Dilbagh Panchal Author-X-Name-First: Dilbagh Author-X-Name-Last: Panchal Author-Name: Umesh Jamwal Author-X-Name-First: Umesh Author-X-Name-Last: Jamwal Author-Name: Priyank Srivastava Author-X-Name-First: Priyank Author-X-Name-Last: Srivastava Author-Name: Kushal Kamboj Author-X-Name-First: Kushal Author-X-Name-Last: Kamboj Author-Name: Rohit Sharma Author-X-Name-First: Rohit Author-X-Name-Last: Sharma Title: Fuzzy methodology application for failure analysis of transmission system Abstract: The aim of this research work is to propose a fuzzy methodology-based integrated framework for the failure analysis of the transmission system of the TATA Company-made heavy commercial vehicle. Under the failure analysis failure mode effect analysis (FMEA) approaches has been applied and the critical components of the considered system were identified on the basis of their risk priority number (RPN). The identification of critical components on the basis of RPN score results in confusion to system analyst as it becomes difficult to allocate appropriate risk priorities under same RPN scores. Also, importance among the probability of occurrence of failure (O<SUB align="right"><SMALL>f</SMALL></SUB>), severity (S), probability of non-detection (O<SUB align="right"><SMALL>d</SMALL></SUB>) are assumed to be of same importance, however, in real practical application there exists relative importance among these three factors. Therefore, to overcome such types of limitations of FMEA approach a fuzzy decision making system (FDMS) and grey relation analysis (GRA) approaches were applied. The ranking results so obtained were compared for better and intelligent decision making of risky components and the results were further supplied to maintenance management/reliability engineer of the considered system for planning and implementing the suitable maintenance policy accordingly. Journal: Int. J. of Mathematics in Operational Research Pages: 220-237 Issue: 2 Volume: 12 Year: 2018 Keywords: transmission system; fuzzy methodology; reliability; failure mode effect analysis; FMEA; fuzzy decision making system; FDMS; grey relation analysis; GRA. File-URL: http://www.inderscience.com/link.php?id=89678 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:220-237 Template-Type: ReDIF-Article 1.0 Author-Name: Geeta Sachdev Author-X-Name-First: Geeta Author-X-Name-Last: Sachdev Title: Symmetric duality for multi-objective second-order fractional programs Abstract: A pair of symmetric dual second-order multi-objective fractional programming programs is formulated. Various duality results are established for this pair which further helps to study minimax mixed integer programming problems. Symmetric duality theorem is established under pseudobonvexity and multiplicative separability assumptions on the functions involved. Journal: Int. J. of Mathematics in Operational Research Pages: 238-252 Issue: 2 Volume: 12 Year: 2018 Keywords: symmetric duality; multi-objective programming; minimax mixed integer programming; fractional programming. File-URL: http://www.inderscience.com/link.php?id=89679 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:238-252 Template-Type: ReDIF-Article 1.0 Author-Name: Tseng-Chang Yen Author-X-Name-First: Tseng-Chang Author-X-Name-Last: Yen Author-Name: Kuo-Hsiung Wang Author-X-Name-First: Kuo-Hsiung Author-X-Name-Last: Wang Title: Cost benefit analysis of three systems with imperfect coverage and standby switching failures Abstract: The cloud computing is an emerging new computing paradigm which provides high reliability, high availability, and QoS-guaranteed computing services. The reliability and stability of power supply is one of the most important factors in successful cloud computing. In this paper, we compare three different configurations with imperfect coverage and standby switching failures based on system reliability and availability. The time-to-repair and the time-to-failure for each of the primary and warm standby components are assumed to be exponentially distributed. We derive the explicit expressions for mean time-to-failure, <i>MTTF</i>, and steady-state availability, <i>A<SUB align="right"><SMALL>T</SMALL></SUB></i>(&infin;), for three configurations and perform a comparative analysis. Three configurations are ranked based on MTTF, <i>A<SUB align="right"><SMALL>T</SMALL></SUB></i>(&infin;), and cost/benefit where benefit is either MTTF or <i>A<SUB align="right"><SMALL>T</SMALL></SUB></i>(&infin;). Journal: Int. J. of Mathematics in Operational Research Pages: 253-272 Issue: 2 Volume: 12 Year: 2018 Keywords: availability; comparisons; imperfect coverage; reliability; standby switching failures. File-URL: http://www.inderscience.com/link.php?id=89680 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:253-272 Template-Type: ReDIF-Article 1.0 Author-Name: V.V. Singh Author-X-Name-First: V.V. Author-X-Name-Last: Singh Author-Name: Hamisu I. Ayagi Author-X-Name-First: Hamisu I. Author-X-Name-Last: Ayagi Title: Stochastic analysis of a complex system under preemptive resume repair policy using Gumbel-Hougaard family copula Abstract: The present paper focuses on the study of complex system consisting of three units super priority, priority and ordinary unit under preemptive resume repair policy. Three units connected with an automatic changeover switch and human operator is handling the system. Together with the failure in super priority, priority and ordinary unit, the other important failures like deliberate failure and switch failure have been considered for study of mathematical model. All failure rates are assumed constant and follow exponential distribution however, the repair rate for partially failed state follow general distribution and complete failed states are repaired using Gumbel-Hougaard family copula (a joint probability distribution of general distribution and negative exponential distribution). The system is analysed using supplementary variable technique and Laplace transform. The various popular measures of reliability such as availability, reliability, mean time to failure (MTTF) and profit function has been calculated for particular values of failure and repair rates. Sensitivity analysis for different traditional measures has also been done. Computed results have been highlighted by tables and graphs. Journal: Int. J. of Mathematics in Operational Research Pages: 273-291 Issue: 2 Volume: 12 Year: 2018 Keywords: availability; reliability; human failure; switch failure; preemptive resume repair policy; super priority unit; priority unit; profit function. File-URL: http://www.inderscience.com/link.php?id=89681 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:2:p:273-291 Template-Type: ReDIF-Article 1.0 Author-Name: Binay Kumar Author-X-Name-First: Binay Author-X-Name-Last: Kumar Title: Unreliable bulk queueing model with optional services, Bernoulli vacation schedule and balking Abstract: This paper deals with <i>M<SUP align="right"><SMALL>X</SMALL></SUP></i>/<i>G</i>/1 queueing system in which arriving units join a single waiting line. Server provides the first essential service and one of the optional services among <i>m</i> available optional services, to all arriving units. After completion of both phases of services of each unit the server may take optional vacation with probability <i>p</i>. It is assumed that during any phase of service, server may stop working due to random failure and is sent for repair. Further it is assumed that arriving units may balk from the system when server is busy, vacation and under repair with probability <i><span style="text-decoration: overline">b</span></i> = 1 &minus; <i>b</i>. Using the probability generating functions we derive the queue size distribution at different time points as well as waiting time distribution. Finally numerical illustration is provided to analyse the sensitivity of different parameters on various performance measures. Journal: Int. J. of Mathematics in Operational Research Pages: 293-316 Issue: 3 Volume: 12 Year: 2018 Keywords: bulk arrival; Bernoulli vacation; optional services; balking; random breakdown; supplementary variable. File-URL: http://www.inderscience.com/link.php?id=90799 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:293-316 Template-Type: ReDIF-Article 1.0 Author-Name: T. Jayanth Kumar Author-X-Name-First: T. Jayanth Author-X-Name-Last: Kumar Author-Name: Purusotham Singamsetty Author-X-Name-First: Purusotham Author-X-Name-Last: Singamsetty Title: An exact algorithm for multi-constrained minimum spanning tree problem Abstract: This paper deals with a variant of minimum spanning tree problem with multiple constraints, which includes degree, weight and budgeting constraints simultaneously together. To model the problem, a zero-one programming is incorporated. An exact solution procedure called pattern recognition technique-based lexi-search algorithm is developed. A suitable numerical illustration is given to check the applicability of the developed algorithm. Furthermore, the algorithm is programmed in C and tested with randomly generated hard instances, computational results are also reported. The overall results reveal that the proposed algorithm is fairly proficient in the sense of both acquiring the optimal solutions and computational time. Journal: Int. J. of Mathematics in Operational Research Pages: 317-330 Issue: 3 Volume: 12 Year: 2018 Keywords: multi-constrained minimum spanning tree; lexi-search algorithm; pattern recognition technique; weight constraint; degree constraint; budgeting constraint. File-URL: http://www.inderscience.com/link.php?id=90800 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:317-330 Template-Type: ReDIF-Article 1.0 Author-Name: Deepa Khurana Author-X-Name-First: Deepa Author-X-Name-Last: Khurana Author-Name: Rekha Rani Chaudhary Author-X-Name-First: Rekha Rani Author-X-Name-Last: Chaudhary Title: An order level inventory model for deteriorating stock product and time dependent demand under shortages Abstract: The objective of the present paper is to develop an inventory model for deteriorating products. In this paper the demand is a function of time and available stock level since the available stock level is an important tool to attract the customers. The shortages are allowed and partially backlogged. Depending on the rate of backlogging two different cases are developed. In the first case, the rate of backlogging is constant and in another case the backlogging rate is time dependent. Numerical example is given to illustrate the model and its significant feature. Sensitivity analysis is also carried out to study the effect of different parameters on total average cost. Journal: Int. J. of Mathematics in Operational Research Pages: 331-349 Issue: 3 Volume: 12 Year: 2018 Keywords: deterioration; shortages; stock and time dependent demand; partial backlogging. File-URL: http://www.inderscience.com/link.php?id=90801 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:331-349 Template-Type: ReDIF-Article 1.0 Author-Name: Deo Datta Aarya Author-X-Name-First: Deo Datta Author-X-Name-Last: Aarya Author-Name: Mukesh Kumar Author-X-Name-First: Mukesh Author-X-Name-Last: Kumar Title: A production inventory model with selling price and stock sensitive demand under partial backlogging Abstract: In the proposed paper we develop an inventory model for instantaneous deteriorating items with multi variate function of demand rate. Generally, we observe that the demand for any product depends on so many factors, out of which the available stock and selling price are the main factors. So in this paper we have assumed that the demand rate is a function of stock and selling price. The production rate is taken as a function of demand rate. The shortages are allowed and it is assumed that the occurring shortages will be backlogged for which the backlogging rate is a function of waiting time. The numerical example and sensitivity exploration with respect to various parameters are also cited to illustrate the study. Journal: Int. J. of Mathematics in Operational Research Pages: 350-363 Issue: 3 Volume: 12 Year: 2018 Keywords: inventory; shortages and partial backlogging; multi variate demand rate; deterioration rate; production. File-URL: http://www.inderscience.com/link.php?id=90802 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:350-363 Template-Type: ReDIF-Article 1.0 Author-Name: Mohamed Abd El-Hady Kassem Author-X-Name-First: Mohamed Abd El-Hady Author-X-Name-Last: Kassem Author-Name: Mohamed Abd Allah El-Hadidy Author-X-Name-First: Mohamed Abd Allah Author-X-Name-Last: El-Hadidy Title: On duality of fuzzy multiobjective optimisation problems: application to a multiplicative search technique Abstract: In this paper, we present a new study to minimise the expected value of the first meeting time between one of the searchers and the randomly moving target in the space (case of the multiplicative search technique) from a viewpoint of computational optimisation. We introduce the dual problem for the fuzzy multiobjective nonlinear programming problem (FMONLP) with inequality constraints which is obtained in El-Hadidy [<i>International Journal of Computational Methods</i>, Vol. 13, No. 6 (2016) 1650038 (38 pages)]. For this problem, we generalise the following classes of the vector-valued functions for fuzzy sets: weak strictly pseudo-quasi type I, strong pseudo-quasi type I, weak quasi strictly type I and weak strictly pseudo type I. We provide the fuzzy forms of Mond-Weir and general Mond-Weir duals for the involved problem and consequently various duality results are derived. Journal: Int. J. of Mathematics in Operational Research Pages: 364-377 Issue: 3 Volume: 12 Year: 2018 Keywords: multiplicative search technique; convex fuzzy mappings; invex fuzzy mappings; multiobjective nonlinear programming; weak strictly pseudo type I. File-URL: http://www.inderscience.com/link.php?id=90803 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:364-377 Template-Type: ReDIF-Article 1.0 Author-Name: Nita H. Shah Author-X-Name-First: Nita H. Author-X-Name-Last: Shah Author-Name: Mrudul Y. Jani Author-X-Name-First: Mrudul Y. Author-X-Name-Last: Jani Author-Name: Urmila Chaudhari Author-X-Name-First: Urmila Author-X-Name-Last: Chaudhari Title: Optimal ordering policy for deteriorating items under down-stream trade credit dependent quadratic demand with full up-stream trade credit and partial down-stream trade credit Abstract: Nowadays, the use of the offer of delay payment is a very impressive tool to boost the market demand by attracting more customers. In this paper, we propose an inventory model, in which a retailer receives a permissible delay on the entire purchase expanse from the manufacturer (i.e., an up-stream full trade credit). In comparison, the retailer asks customers to pay some percent of purchasing cost at the time of receiving the product to reduce default risk (i.e., a down-stream partial trade credit). We consider the product with maximum fixed-life time deterioration and to reduce deterioration of the product, seller spends capital on preservation technology to preserve the item. Here, down-stream trade credit dependent quadratic demand is debated which is suitable for the products whose demand increases initially and afterward it starts to decrease. Industries like fashion and electronics most probably deals with this type of demand. The objective is to minimise the total relevant cost of retailer with respect to cycle time, down-stream trade credit and investment for preservation technology. The model is supported with numerical examples. Sensitivity analysis is done to derive insights for decision-maker. Graphical results, in three dimensions, are exhibited with supervisory decisions. Journal: Int. J. of Mathematics in Operational Research Pages: 378-396 Issue: 3 Volume: 12 Year: 2018 Keywords: inventory; deterioration; fixed-life time; quadratic demand; preservation investment; partial down-stream trade credit; full up-stream trade credit. File-URL: http://www.inderscience.com/link.php?id=90804 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:378-396 Template-Type: ReDIF-Article 1.0 Author-Name: Mohammad Mohammadi Author-X-Name-First: Mohammad Author-X-Name-Last: Mohammadi Title: Simultaneous selection factories, assignment products to factories, lot-sizing and scheduling in distributed permutation flow shop Abstract: The simultaneous selection factory's problem has been recently proposed as a generalisation in distributed permutation flow shop setting. In this paper, a new generalisation of simultaneous lot-sizing and scheduling decisions in permutation flow shop problem to the distributed permutation flow shop has been studied. Under this generalisation, it is not necessary to use all existing factories and each product cannot be produced in more than one factory. An exact formulation of the problem provided as a mixed integer program. In order to solve the problem, a heuristic procedure has been developed. To test the accuracy of heuristic, a lower bound is developed and compared against the optimal solution. Journal: Int. J. of Mathematics in Operational Research Pages: 397-412 Issue: 3 Volume: 12 Year: 2018 Keywords: distributed permutation flow shop; lot-sizing and scheduling; sequence-dependent; assignment. File-URL: http://www.inderscience.com/link.php?id=90811 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:397-412 Template-Type: ReDIF-Article 1.0 Author-Name: Mushtaq Ahmad Lone Author-X-Name-First: Mushtaq Ahmad Author-X-Name-Last: Lone Author-Name: Shakeel Ahmad Mir Author-X-Name-First: Shakeel Ahmad Author-X-Name-Last: Mir Author-Name: Imran Khan Author-X-Name-First: Imran Author-X-Name-Last: Khan Title: Allocation problem in the presence of non-response: a mathematical programming approach Abstract: Survey non-response refers to the failure to get a useable response from the respondent selected for the sample. Non-response may occur due to several reasons. The randomised response technique (<i>RRT</i>) presented by Warner (1965) used to estimate proportion of respondents to the sensitive questions without revealing his choice to the interviewer. In this article, the problem of optimal allocation in stratified sampling where <i>RRT</i> is used in presence of non-response, is formulated as an nonlinear programming problem (<i>NLPP</i>). The formulated problem is solved using branch and bound method and the results are obtained through LINGO. Journal: Int. J. of Mathematics in Operational Research Pages: 413-421 Issue: 3 Volume: 12 Year: 2018 Keywords: stratified random sampling; optimum allocation; randomised response technique; RRT; non-response; branch and bound method; nonlinear programming problem; NLPP. File-URL: http://www.inderscience.com/link.php?id=90814 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:3:p:413-421 Template-Type: ReDIF-Article 1.0 Author-Name: Trailokyanath Singh Author-X-Name-First: Trailokyanath Author-X-Name-Last: Singh Author-Name: Pandit Jagatananda Mishra Author-X-Name-First: Pandit Jagatananda Author-X-Name-Last: Mishra Author-Name: Hadibandhu Pattanayak Author-X-Name-First: Hadibandhu Author-X-Name-Last: Pattanayak Title: An EOQ inventory model for deteriorating items with time-dependent deterioration rate, ramp-type demand rate and shortages Abstract: This paper presents an economic order quantity (EOQ) model for deteriorating items having time proportional deterioration rate, time dependent ramp-type demand rate and shortages. Shortages are allowed to occur in the inventory system and completely backlogged. The ramp-type demand rate is deterministic and varies with time up to a certain point and then becomes constant. The three-parameter Weibull distribution rate indicates the change in deterioration rate with respect to time and takes into account of the items which are already deteriorated while receiving into an inventory system as well as items those might start deteriorating in future. To start with, the model is developed for shortages, but is also valid for the seasonal items and newly launched high tech products like computers, laptops, mobile phones and automobiles, etc. The purpose of this study is to develop an optimal policy, so that the average total cost is minimised by optimising the procurement time point. Furthermore, the solution procedure and the numerical example are provided to illustrate the proposed model. Finally, sensitivity analysis of the various parameters on optimal solution is carried out. Journal: Int. J. of Mathematics in Operational Research Pages: 423-437 Issue: 4 Volume: 12 Year: 2018 Keywords: deteriorating items; economic order quantity; EOQ; ramp-type demand; shortages; time-dependent deterioration rate. File-URL: http://www.inderscience.com/link.php?id=92103 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:423-437 Template-Type: ReDIF-Article 1.0 Author-Name: Parakramaweera Sunil Dharmapala Author-X-Name-First: Parakramaweera Sunil Author-X-Name-Last: Dharmapala Title: Bias-correction in DEA efficiency scores using simulated beta samples: an alternative view of bootstrapping in DEA Abstract: Bootstrapping of DEA efficiency scores came into being under the criticism that DEA input/output data may contain random error, and as a result the efficient frontier may be warped by statistical noise. Since the publication of the seminal paper by Simar and Wilson (1998), several researchers have carried out bootstrapping the DEA frontier, re-computing the efficiency scores after correcting the biases and developing confidence intervals for bias-corrected scores. We view bias-correction in DEA efficiency scores from a different perspective by randomising the efficiency scores that follow underlying beta distributions. In a step-by-step process, using the simulated beta samples, we show how to correct the biases of individual scores, construct confidence intervals for the bias-corrected mean scores and derive some statistical results for the estimators used in the process. Finally, we demonstrate this method by applying it to a set of banks. Journal: Int. J. of Mathematics in Operational Research Pages: 438-456 Issue: 4 Volume: 12 Year: 2018 Keywords: data envelopment analysis; DEA; assurance regions; AR; order statistics; beta distribution; bias-correction; simulation. File-URL: http://www.inderscience.com/link.php?id=92104 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:438-456 Template-Type: ReDIF-Article 1.0 Author-Name: Promila Kumar Author-X-Name-First: Promila Author-X-Name-Last: Kumar Author-Name: Jyoti Author-X-Name-First: Author-X-Name-Last: Jyoti Title: Duality for non-differentiable multi-objective semi-infinite programming for higher order invex functions Abstract: This paper deals with non-differentiable multi-objective semi-infinite programming problem. It is a problem of simultaneous minimisation of finitely many scalar valued functions subject to an arbitrary (possibly infinite) set of constraints. Non-differentiability enters, due to the square root of a quadratic form which appears in the objective functional. Concept of efficiency of order <i>m</i> has been extended to the above stated problem. In order to study this new solution concept, the notion of <i>ρ</i>-invexity of order <i>m</i> is also proposed which is utilised to establish sufficient optimality conditions for the non-differentiable multi-objective semi-infinite programming problem. Mond-Weir type of dual is proposed for which weak, strong and strict converse duality theorems are established. Journal: Int. J. of Mathematics in Operational Research Pages: 457-470 Issue: 4 Volume: 12 Year: 2018 Keywords: optimality; duality; semi-infinite programming; non-differentiable programming; ρ-invexity of order m. File-URL: http://www.inderscience.com/link.php?id=92105 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:457-470 Template-Type: ReDIF-Article 1.0 Author-Name: Ahmed Bensalma Author-X-Name-First: Ahmed Author-X-Name-Last: Bensalma Title: Testing the fractional integration parameter revisited: a fractional Dickey-Fuller test Abstract: The main scope of this paper is to provide how to extend the standard Dickey-Fuller test (1979) by taking into account the fractional case. Such extension has already been discussed by Dolado et al. (2002). In this paper, we show, in the first step, that the fractional Dickey-Fuller test proposed by Dolado et al. is useless in practice. In the second step we show how to extend adequately the standard framework of Dickey-Fuller test to take into account the fractional case by using the usual test statistics and the usual asymptotic distributions (Phillips, 1987). Such extension can be very useful in practice. Through a simulation study, we show the good performance of the test in terms of size and power. Finally, in order to show how to use the new testing procedure, the test is applied to the well-known Nelson and Plosser data. Journal: Int. J. of Mathematics in Operational Research Pages: 471-506 Issue: 4 Volume: 12 Year: 2018 Keywords: fractional integration; fractional unit root; Dickey-Fuller; unit root test; fractional Dickey-Fuller test. File-URL: http://www.inderscience.com/link.php?id=92106 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:471-506 Template-Type: ReDIF-Article 1.0 Author-Name: Yasmina Djabali Author-X-Name-First: Yasmina Author-X-Name-Last: Djabali Author-Name: Boualem Rabta Author-X-Name-First: Boualem Author-X-Name-Last: Rabta Author-Name: Djamil Aïssani Author-X-Name-First: Djamil Author-X-Name-Last: Aïssani Title: Approximating service-time distributions by phase-type distributions in single-server queues: a strong stability approach Abstract: Phase-type queueing systems are used to approximate queues with general service-time distributions. In this work, we provide by means of the strong stability method, the mathematical justification of the approximation method by phase-type distributions that is already used in several works. We consider the approximation of <i>M</i>/<i>G</i>/1 queueing system by a <i>M</i>/<i>PH</i>/1 system, where PH refers to a hyperexponential <i>H</i><SUB align="right"><SMALL>2</SMALL></SUB> or a hypoexponential <i>HOE</i><SUB align="right"><SMALL>2</SMALL></SUB> distribution depending on the value of the coefficient of variation of the original distribution. We prove the robustness of the underlying Markov chain in each case and estimate an upper bound of the deviation of the stationary vector, resulting from the perturbation of the service-time distribution. We provide numerical examples and compare the perturbation bounds obtained in this paper with the estimates of the real deviation of the stationary vector obtained by simulation. Journal: Int. J. of Mathematics in Operational Research Pages: 507-531 Issue: 4 Volume: 12 Year: 2018 Keywords: queueing systems; phase-type distributions; perturbation; sensitivity analysis; strong stability; quantitative estimates; perturbation bounds. File-URL: http://www.inderscience.com/link.php?id=92107 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:507-531 Template-Type: ReDIF-Article 1.0 Author-Name: Debiprasad Acharya Author-X-Name-First: Debiprasad Author-X-Name-Last: Acharya Author-Name: Manjusri Basu Author-X-Name-First: Manjusri Author-X-Name-Last: Basu Author-Name: Atanu Das Author-X-Name-First: Atanu Author-X-Name-Last: Das Title: On logarithmic fixed-charge transportation problem Abstract: The fixed-charge transportation problem (FCTP) is still a challenging problem in the field of mathematical programming. In this paper, we consider fixed-charge transportation problem with logarithmic objective function. In the absence of any suitable algorithm to obtain the solution of this type of nonlinear transportation problem, we discuss the advantage of polynomial approximation. There exists a major difference between the two problems that the variables in the polynomial transportation problem have no upper bound but in the logarithmic transportation problem they are bounded. Using the expansion of logarithm we show the resemblance between the structural behaviour of linear and fixed-charge transportation problems. We illustrate a numerical example in support of the developed method. Journal: Int. J. of Mathematics in Operational Research Pages: 532-541 Issue: 4 Volume: 12 Year: 2018 Keywords: transportation problem; fixed cost; logarithm modelling. File-URL: http://www.inderscience.com/link.php?id=92108 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:532-541 Template-Type: ReDIF-Article 1.0 Author-Name: Kenneth Barroga Author-X-Name-First: Kenneth Author-X-Name-Last: Barroga Title: A mathematical investigation of Rao diversity coefficients among the communities according to species morphometry and species taxonomy Abstract: Although Rao diversity coefficient (Rao DIVC) is sensitive to the differences among species, a gap still remains in investigating how the communities are affected when the dissimilarity among the species are in terms of its morphometry and taxonomy. I studied the effect of using species taxonomic classification and species morphometrical traits in the computation of Rao DIVC in assessing diversity of ecological communities. I utlised the Mahalanobis distance for measuring the variation of species morphometry. As for species taxonomy, I employed the method by Warwick and Clarke (1995). When the calculated Rao DIVCs, double principal coordinate analysis and co-inertia analysis outputs were compared, I discovered that Rao DIVCs accounting species morphometry (<i>R<SUB align="right"><SMALL>sm</SMALL></SUB></i>) and species taxonomy (<i>R<SUB align="right"><SMALL>st</SMALL></SUB></i>) yielded different results and interpretation. <i>R<SUB align="right"><SMALL>sm</SMALL></SUB></i> clearly showed more the variation among communities but contributed less in the analysis, whereas <i>R<SUB align="right"><SMALL>st</SMALL></SUB></i> showed more clearly the clusters between the communities which make the interpretation easier. Journal: Int. J. of Mathematics in Operational Research Pages: 542-564 Issue: 4 Volume: 12 Year: 2018 Keywords: double principal coordinate analysis; DPCoA; Mahalanobis distance; Rao diversity coefficient; Rao DIVC; co-inertia analysis; COIA. File-URL: http://www.inderscience.com/link.php?id=92109 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:12:y:2018:i:4:p:542-564 Template-Type: ReDIF-Article 1.0 Author-Name: Javier Martínez-Gómez Author-X-Name-First: Javier Author-X-Name-Last: Martínez-Gómez Author-Name: Ricardo A. Narváez C. Author-X-Name-First: Ricardo A. Narváez Author-X-Name-Last: C. Title: Material selection for multi-tubular fixed bed reactor Fischer-Tropsch reactor Abstract: Multi-tubular, fixed bed, Fischer-Tropsch reactor (MFBR) appears as an essential technology for the energy future; moreover it is required to improve and to reduce operation costs. This research used multi-criteria decision making methods (MCDM) for the material selection of a MFBR. It focused on fulfilling the technological requirements for constructing the vessel and piping of a MFBR, while costs reduction is considered as part of the analysis. The MCMD methods are complex proportional assessments of alternatives which apply methods such as grey relations (COPRAS-G), operational competitiveness rating analysis (OCRA), a new additive ratio assessment (ARAS) and technique for order of preference by similarity to ideal solution (TOPSIS). The criteria weighting was performed by compromised weighting method composed of analytic hierarchy process (AHP) and entropy methods. The ranking results showed that ASME SA-106 and ASME SA-106 29 would be the best materials for the vessel and piping of a MFBR. Journal: Int. J. of Mathematics in Operational Research Pages: 1-29 Issue: 1 Volume: 13 Year: 2018 Keywords: multi-criteria decision making methods; MCDM; multi-tubular fixed bed reactor Fischer-Tropsch reactor; MFBR; material selection. File-URL: http://www.inderscience.com/link.php?id=92956 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:1-29 Template-Type: ReDIF-Article 1.0 Author-Name: Soodabeh Asadi Author-X-Name-First: Soodabeh Author-X-Name-Last: Asadi Author-Name: Hossein Mansouri Author-X-Name-First: Hossein Author-X-Name-Last: Mansouri Author-Name: Maryam Zangiabadi Author-X-Name-First: Maryam Author-X-Name-Last: Zangiabadi Title: An interior-point algorithm for horizontal linear complementarity problems Abstract: This paper presents a wide-neighbourhood interior-point algorithm for P-horizontal linear complementarity problem. The convergence analysis is shown for the introduced wide neighbourhood of the central path by Ai and Zhang (2005) for monotone linear complementarity problem, and unifies the analysis for its constituent wide neighbourhoods. The Newton search directions are decomposed to the non-negative and non-positive parts, correspond to the parts of the right hand side. The achieved complexity bound is the same as the best obtained bound for the monotone linear complementarity problems, except that it is multiplied by a factor dependent on the handicap of the given problem. Journal: Int. J. of Mathematics in Operational Research Pages: 30-46 Issue: 1 Volume: 13 Year: 2018 Keywords: interior-point method; horizontal linear complementarity problem; HLCP; wide neighbourhood algorithm; polynomial complexity. File-URL: http://www.inderscience.com/link.php?id=92959 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:30-46 Template-Type: ReDIF-Article 1.0 Author-Name: Seyed Hojat Pakzad-Moghaddam Author-X-Name-First: Seyed Hojat Author-X-Name-Last: Pakzad-Moghaddam Author-Name: Farhad Salehian Author-X-Name-First: Farhad Author-X-Name-Last: Salehian Author-Name: Seyed Esa Hosseini Author-X-Name-First: Seyed Esa Author-X-Name-Last: Hosseini Author-Name: Hassan Mina Author-X-Name-First: Hassan Author-X-Name-Last: Mina Title: A hierarchical cellular manufacturing system Abstract: Cellular manufacturing is one of the most common and popular methods in order to take advantage of group technology. Of particular interest, applying cellular manufacturing systems (CMSs) increases the efficiency of the applied transportation system by designing an efficient working floor. Controlling the amount of material handling, results in lower cost and energy required to transport materials/products. Hence, CMS are under consideration in the study at hand. Regarding a hybrid CMS, proper manufacturing systems such as single machines, flow shops, job-shops and open shops are applied between and within cells to harmonise the whole manufacturing procedure. A special case of hybrid CMS, referred to as hierarchical CMS is investigated in this paper. In a HCMS not only machines are placed in several interior cells, but also interior cells themselves must be located in exterior ones. Finally a mixed integer nonlinear programming mathematical model is presented and validated through numerical results. Journal: Int. J. of Mathematics in Operational Research Pages: 47-60 Issue: 1 Volume: 13 Year: 2018 Keywords: cellular manufacturing; CM; energy saving policy; shop floor; mathematical modelling. File-URL: http://www.inderscience.com/link.php?id=92960 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:47-60 Template-Type: ReDIF-Article 1.0 Author-Name: Salim Haddadi Author-X-Name-First: Salim Author-X-Name-Last: Haddadi Author-Name: Meryem Cheraitia Author-X-Name-First: Meryem Author-X-Name-Last: Cheraitia Author-Name: Abdellah Salhi Author-X-Name-First: Abdellah Author-X-Name-Last: Salhi Title: A two-phase heuristic for set covering Abstract: The set covering problem (SCP) is a well-known computationally intractable problem. We suggest here a two-phase heuristic to solve it. The first phase reduces substantially the size of the given SCP by removing some variables; the second phase applies a simple Lagrangian heuristic applied to the reduced problem. Construction and improvement heuristics are embedded in the Lagrangian solution approach. The construction heuristic provides good covers by solving small SCPs. The improvement heuristic inserts these covers into larger ones from which better covers are extracted, again by solving different but also small SCPs. The novelty lies in the reduction of the problem size by an effective variable-fixing heuristic, which, in practice, eliminates up to 95% of the variables of the problem without sacrificing the solution quality. Extensive computational and comparative results are presented. Journal: Int. J. of Mathematics in Operational Research Pages: 61-78 Issue: 1 Volume: 13 Year: 2018 Keywords: set covering; variable-fixing heuristic; greedy heuristic with regret; Lagrangian heuristic. File-URL: http://www.inderscience.com/link.php?id=92962 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:61-78 Template-Type: ReDIF-Article 1.0 Author-Name: Prashanta Majee Author-X-Name-First: Prashanta Author-X-Name-Last: Majee Author-Name: Chandal Nahak Author-X-Name-First: Chandal Author-X-Name-Last: Nahak Title: New generalised mixed vector variational-like inequalities with semi-&eta;-pseudomonotonicity Abstract: In this paper, we introduce the concept of semi-<i>&eta;</i>-pseudomonotonicity for vector set-valued mappings. Using this concept, and utilising KKM technique and Nadler's Lemma, we establish some existence results for the new generalised mixed vector variational-like inequality problem in reflexive Banach spaces. Our results are the extension and improvement of some of the results given by Plubtieng and Thammathiwat (2014). Few examples are given to justify our new findings. Journal: Int. J. of Mathematics in Operational Research Pages: 79-90 Issue: 1 Volume: 13 Year: 2018 Keywords: semi-η-pseudomonotonicity; new generalised mixed vector variational-like inequalities; Fan-KKM theorem; Nadler's result. File-URL: http://www.inderscience.com/link.php?id=92963 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:79-90 Template-Type: ReDIF-Article 1.0 Author-Name: Mei Lee Sam Author-X-Name-First: Mei Lee Author-X-Name-Last: Sam Author-Name: Adi Saptari Author-X-Name-First: Adi Author-X-Name-Last: Saptari Author-Name: Mohd Rizal Bin Salleh Author-X-Name-First: Mohd Rizal Bin Author-X-Name-Last: Salleh Author-Name: Effendi Mohamad Author-X-Name-First: Effendi Author-X-Name-Last: Mohamad Title: Comparison between linear programming and integer linear programming: a review Abstract: This research discusses comparison of linear programming (LP) and integer linear programming (ILP). Two techniques to solve LP, simplex method and interior-point method were introduced. For ILP, available algorithms can be classified into exact algorithms and heuristic algorithms. Three criteria were used to evaluate the characteristics: time complexity, problem size and computational time. Simplex method is effective to solve small sized problems with less number of iterations while interior-point method was recommended for large sized problems due to its excellent performance and shorter computational time than simplex method. Exact algorithms are suitable for small sized problems and attain optimal solution in reasonable computational time. Meanwhile, heuristics outperform exact algorithms in solving large sized problem where it can obtain near optimal solution in an acceptable computational time. Heuristics are not guaranteed to obtain optimal solutions, compared to exact algorithms. Journal: Int. J. of Mathematics in Operational Research Pages: 91-106 Issue: 1 Volume: 13 Year: 2018 Keywords: linear programming; LP; integer linear programming; ILP; computational time; problem's size. File-URL: http://www.inderscience.com/link.php?id=92966 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:91-106 Template-Type: ReDIF-Article 1.0 Author-Name: Amiya Biswas Author-X-Name-First: Amiya Author-X-Name-Last: Biswas Author-Name: Asoke Kumar Bhunia Author-X-Name-First: Asoke Kumar Author-X-Name-Last: Bhunia Author-Name: Ali Akbar Shaikh Author-X-Name-First: Ali Akbar Author-X-Name-Last: Shaikh Title: Multi-objective unbalanced assignment problem with restriction of jobs to agents via NSGA-II Abstract: In this paper, an approach based on genetic algorithm has been proposed for solving multi-objective unbalanced assignment problems with restriction of job(s) to different agents which may arise due to the inability/poor efficiency of performing certain jobs by some agents dealing with an additional constraint on the maximum number of jobs that can be performed by an agent. As the cost and time are considered as the most important factors for managerial decision in economic/industrial establishments, so here the total cost of assignment of jobs to agents and the total time of completion of jobs by the agents are considered as the two prime objectives. This gives rise to an NP-hard 0-1 programming problem and to solve this problem, we have equipped NSGA-II with a newly developed crossover having the capability of repairing infeasible solution and two new mutation schemes. Also, for comparison of the results obtained from this algorithm, some other variants of this algorithm with existing crossover and mutation schemes have been considered. Finally, to illustrate the performance of proposed approach, a set of test problems have been solved and the results have been analysed for different variants of NSGA-II and some potential future research directions has been discussed. Journal: Int. J. of Mathematics in Operational Research Pages: 107-127 Issue: 1 Volume: 13 Year: 2018 Keywords: multi-objective optimisation; unbalanced assignment problem; UNB-AP; genetic algorithm; non-dominated sorting; Pareto-optimal solution. File-URL: http://www.inderscience.com/link.php?id=92967 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:107-127 Template-Type: ReDIF-Article 1.0 Author-Name: C.D. Nandakumar Author-X-Name-First: C.D. Author-X-Name-Last: Nandakumar Author-Name: S. Srinivasan Author-X-Name-First: S. Author-X-Name-Last: Srinivasan Author-Name: R. Sathiyamoorthi Author-X-Name-First: R. Author-X-Name-Last: Sathiyamoorthi Title: Evaluation of reordering time in a manufacturing inventory division Abstract: In this paper, a production process is considered which requires two kinds of raw materials as inputs to make a product. The two kinds of raw materials are stored separately. During the time of crisis like non-availability of the raw materials due to scarcity or delayed delivery or for some other reasons, the reserve stocks are utilised to continue the production process, as a result; the level of reserve stocks would come down and finally may go void. This may result into production halt. To avoid this situation, a reorder is made to maintain the level of reserve inventory as soon as the reserve level touches a particular level called the threshold level. Using the shock model and cumulative damage process technique, a stochastic model is derived to find the threshold level or the time of reordering, which helps the production system to eliminate the holding cost on excessive raw materials and also the loss arising from the shortage of raw materials. Numerical illustrations are provided. Journal: Int. J. of Mathematics in Operational Research Pages: 128-139 Issue: 1 Volume: 13 Year: 2018 Keywords: threshold level; reserve inventory; break down; random time points; depletion. File-URL: http://www.inderscience.com/link.php?id=92968 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:1:p:128-139 Template-Type: ReDIF-Article 1.0 Author-Name: Marcello Braglia Author-X-Name-First: Marcello Author-X-Name-Last: Braglia Author-Name: Davide Castellano Author-X-Name-First: Davide Author-X-Name-Last: Castellano Author-Name: Dongping Song Author-X-Name-First: Dongping Author-X-Name-Last: Song Title: Efficient near-optimal procedures for some inventory models with backorders-lost sales mixture and controllable lead time, under continuous or periodic review Abstract: This paper considers a number of inventory models with backorders-lost sales mixture, stockout costs, and controllable lead time. The lead time is a linear function of the lot size and includes a constant term that is made of several components. These lot-size-independent components are assumed to be controllable. Both single- and double-echelon inventory systems, under periodic or continuous review, are considered. To authors knowledge, these models have never been previously studied in literature. The purpose of this paper is to analyse and optimise these novel inventory models. The optimisation is carried out by means of heuristics that work on an <i>ad hoc</i> approximation of the cost functions. This peculiarity permits to exploit closed-form expressions that make the optimisation procedure simpler and more readily applicable in practice than standard approaches. Finally, numerical experiments investigate the efficiency of the proposed heuristics and the sensitivity of the developed models. Journal: Int. J. of Mathematics in Operational Research Pages: 141-177 Issue: 2 Volume: 13 Year: 2018 Keywords: supply chain; inventory; logistics; lead time; stochastic; heuristics; optimisation; joint economic lot size; stockout. File-URL: http://www.inderscience.com/link.php?id=94053 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:141-177 Template-Type: ReDIF-Article 1.0 Author-Name: Allen H. Tai Author-X-Name-First: Allen H. Author-X-Name-Last: Tai Title: A model for continuously degrading systems with outsourcing maintenance service Abstract: It is a common practice in industry that maintenance service is outsourced to external suppliers. In this paper, a model for a continuously degrading system is developed such that an optimal inspection-maintenance strategy can be derived. The model is capable of handling the situation when there is deferment of the maintenance services. Hence, the system manager can decide whether to stop system operation during the waiting time for the maintenance services. The system is subjected to two degradation sources: 1) the degradation due to the operation of the system; 2) the degradation due to the operation environment. An optimal value of the inter-inspection time and an optimal maintenance threshold are then obtained by numerical methods such that the average availability of the system is maximised. Illustrative examples and some special cases are also provided. Journal: Int. J. of Mathematics in Operational Research Pages: 178-201 Issue: 2 Volume: 13 Year: 2018 Keywords: maintenance outsourcing; degrading system; periodic inspection; availability. File-URL: http://www.inderscience.com/link.php?id=94054 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:178-201 Template-Type: ReDIF-Article 1.0 Author-Name: Mohammad Mehdi Tavakoli Author-X-Name-First: Mohammad Mehdi Author-X-Name-Last: Tavakoli Author-Name: Seyed Mojtaba Sajadi Author-X-Name-First: Seyed Mojtaba Author-X-Name-Last: Sajadi Author-Name: Seyed Ali Sadeghi Aghili Author-X-Name-First: Seyed Ali Sadeghi Author-X-Name-Last: Aghili Title: Proposing a new mathematical model and a meta-heuristic algorithm for scheduling and allocating automated guided vehicle Abstract: One of the substantial things, which has been perceived more than ever by captains of industry in recent years, is the necessity of earning competitive value. As a result, mechanisation and enhancing the level of automation of the process has become one of the most fascinating issues to researchers. In this regard one of the most appealing systems to industries is flexible manufacturing systems which contribute to achievement of higher levels of automation in business environments. Since transportation plays an essential role in flexible production systems, automated guided vehicles (AVGs) have been utilised to carry material in these systems in order to maintain the flexibility, and increase the efficiency of production and distribution throughout the system. In this paper, a mathematical model for scheduling and allocating AVGs in the manufacturing process of a specific project is proposed and in the end, a heuristic algorithm is proposed and used to solve the model problem. Journal: Int. J. of Mathematics in Operational Research Pages: 202-218 Issue: 2 Volume: 13 Year: 2018 Keywords: mathematical model; automated guided vehicle; AGV; scheduling and allocation; NSGA II. File-URL: http://www.inderscience.com/link.php?id=94055 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:202-218 Template-Type: ReDIF-Article 1.0 Author-Name: Zidani Nesrine Author-X-Name-First: Zidani Author-X-Name-Last: Nesrine Author-Name: Djellab Natalia Author-X-Name-First: Djellab Author-X-Name-Last: Natalia Title: On the multiserver retrial queues with negative arrivals Abstract: The paper deals with an M/M/C/K retrial queue with exponential abandonment at which positive and negative customers arrive according to Poisson processes. This model is of practical interest: it can be used for analysing the performance in call centres and e-mail contact systems. For the model under investigation, we find the ergodicity conditions and also the approximate solution by using finite truncation and value extrapolation methods. We present some numerical results to examine the performance of the value extrapolation method as well as the system performance. Journal: Int. J. of Mathematics in Operational Research Pages: 219-242 Issue: 2 Volume: 13 Year: 2018 Keywords: abandonment; truncation; ergodicity condition; extrapolation; negative arrivals. File-URL: http://www.inderscience.com/link.php?id=94056 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:219-242 Template-Type: ReDIF-Article 1.0 Author-Name: Dipak Barman Author-X-Name-First: Dipak Author-X-Name-Last: Barman Author-Name: Barun Das Author-X-Name-First: Barun Author-X-Name-Last: Das Title: An imprecise-inventory model with PEND and SEND policy Abstract: A continuous review economic order quantity (EOQ) model (with shortage) is modelled here. The inventory cost parameters are imprecise in nature. The model is developed for <i>Partially Enforced Delay</i> (PEND) and <i>Strictly Enforced Delay</i> (SEND) policies with lead time crashing cost. Here demand of the item is a linear function of selling price and usable lead time. For each policy, a set-up cost reduction technique has been applied to the model. Moreover, a statistical <i>t</i>-test has been used to compare the policies. We also present some numerical examples, sensitivity analysis and their discussions to stabilise the model. Journal: Int. J. of Mathematics in Operational Research Pages: 243-268 Issue: 2 Volume: 13 Year: 2018 Keywords: continuous review policy; imprecise cost; controllable lead time; setup cost reduction; Fisher's t-test. File-URL: http://www.inderscience.com/link.php?id=94057 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:243-268 Template-Type: ReDIF-Article 1.0 Author-Name: Dilip Kumar Adhwarjee Author-X-Name-First: Dilip Kumar Author-X-Name-Last: Adhwarjee Title: Finding the shortest path by Adhwarjee's algorithm and comparison of this powerful method with Dijkstra's algorithm Abstract: This paper introduces an algorithm for finding the shortest path which is more powerful method than all the existing methods like Dijkstra's algorithm. Adhwarjee's algorithm is introduced to the readers for finding the shortest path. The author gives few steps to find the shortest path. This method takes less standard time than Dijkstra's algorithm. First, Dijkstra's method is explained in brief, which is readily available in books. We will concentrate on the new method of finding the shortest path. Adhwarjee's algorithm needs no table to compute. Simple addition, subtraction and finding minimum, maximum can be done mentally and posted in the network itself. In the network, the reader can see the minimum distance or time which requires to be found out. Journal: Int. J. of Mathematics in Operational Research Pages: 269-279 Issue: 2 Volume: 13 Year: 2018 Keywords: origin; destination; vertex; shortest path; minimum. File-URL: http://www.inderscience.com/link.php?id=94058 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:2:p:269-279 Template-Type: ReDIF-Article 1.0 Author-Name: Ouiza Zerdani Author-X-Name-First: Ouiza Author-X-Name-Last: Zerdani Author-Name: Farida Achemine Author-X-Name-First: Farida Author-X-Name-Last: Achemine Title: On optimisation over the integer efficient set in fuzzy linear multicriteria programming Abstract: The problem of optimising a linear function over the efficient set of a multiobjective linear programming problem is an important field of research and has some applications in multiple objective decision making. The main difficulty of this problem is that its feasible domain is non-convex and not described explicitly. The main purpose of this paper is to describe an efficient and finite new algorithm which provides a global <i>R</i>-optimal solution of the problem of optimising a fuzzy linear function over the efficient set of a fuzzy multiobjective integer linear programming (<i>FMOILP</i>) problem without having to search all integer <i>R</i>-efficient solutions. All the parameters of the considered problem are characterised by trapezoidal fuzzy numbers. The proposed approach is based first on the concept of comparison of fuzzy numbers by using ranking function and on an extension of Jorge's algorithm onto fuzzy numbers. Finally a numerical illustration is included for illustration. Journal: Int. J. of Mathematics in Operational Research Pages: 281-302 Issue: 3 Volume: 13 Year: 2018 Keywords: integer programming; global optimisation; optimisation over the efficient set; ranking function; trapezoidal fuzzy numbers. File-URL: http://www.inderscience.com/link.php?id=94847 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:281-302 Template-Type: ReDIF-Article 1.0 Author-Name: Rahul Goel Author-X-Name-First: Rahul Author-X-Name-Last: Goel Title: Partial backlogging EOQ model with trade-credit facility and inflationary environment Abstract: In this article, an economic order quantity (EOQ) model for deteriorating items with trade-credit facility is presented. It is assumed that decay rate is two parameter Weibull distributed function of time. Demand rate of the products increases with time. Shortages are allowed and partially backlogged. The whole study is done in inflationary environment. A numerical assessment is done to exemplify the proposed model and sensitivity analysis with respect to the change in system parameters is also carried out. Journal: Int. J. of Mathematics in Operational Research Pages: 303-319 Issue: 3 Volume: 13 Year: 2018 Keywords: economic order quantity; EOQ; Inlation; inventory; Weibull deterioration; shortages. File-URL: http://www.inderscience.com/link.php?id=94848 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:303-319 Template-Type: ReDIF-Article 1.0 Author-Name: B. Praba Author-X-Name-First: B. Author-X-Name-Last: Praba Author-Name: G. Gomathi Author-X-Name-First: G. Author-X-Name-Last: Gomathi Author-Name: Vijaya Mani Author-X-Name-First: Vijaya Author-X-Name-Last: Mani Author-Name: M. Vageesh Author-X-Name-First: M. Author-X-Name-Last: Vageesh Title: An application of multi-layered fuzzy attributed rough set in studying organisational culture system Abstract: In this paper, the concept of rough set is introduced for an information system with multi-layered weighted fuzzy attributes. The equivalence classes of the objects are formed using the fuzzy weight given to the objects in terms of these multi-layered weighted fuzzy attributes. The weight of the rough set is also defined using the weight of its lower and upper approximations and also we defined an interval valued fuzzy set on the set of objects. This helps to study the behaviour of any system with complex attributes. These concepts are illustrated with a real-time example. Journal: Int. J. of Mathematics in Operational Research Pages: 320-331 Issue: 3 Volume: 13 Year: 2018 Keywords: rough set; information system; lower approximation; upper approximation; equivalence classes. File-URL: http://www.inderscience.com/link.php?id=94849 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:320-331 Template-Type: ReDIF-Article 1.0 Author-Name: Lahcene Guezouli Author-X-Name-First: Lahcene Author-X-Name-Last: Guezouli Author-Name: Samir Abdelhamid Author-X-Name-First: Samir Author-X-Name-Last: Abdelhamid Title: Multi-objective optimisation using genetic algorithm based clustering for multi-depot heterogeneous fleet vehicle routing problem with time windows Abstract: Efficient routing and scheduling of vehicles has significant economic implications for both the public and private sectors. For this purpose, we propose in this study a decision support system which aims to optimise the classical capacitated vehicle routing problem by considering the existence of different vehicle types (with distinct capacities and costs) and multiple available depots, that we call the multi-depot heterogeneous vehicle routing problem with time window (MDHVRPTW) by respecting a set of criteria including: schedules requests from clients, the heterogeneous capacity of vehicles...., and we solve this problem by proposing a new scheme based on the application of the bio-inspired genetic algorithm heuristics and by embedding a clustering algorithm within a VRPTW optimisation frame work, that we will specify later. Computational experiments with the benchmark test instances confirm that our approach produces acceptable quality solutions compared with the best previous results in similar problems in terms of generated solutions and processing time. Experimental results prove that our proposed genetic algorithm is effective in solving the MDHVRPTW problem and hence has a great potential. Journal: Int. J. of Mathematics in Operational Research Pages: 332-349 Issue: 3 Volume: 13 Year: 2018 Keywords: multi-depot vehicle routing problem; clustering; routing; scheduling; genetic algorithm; heterogeneous vehicle routing problem. File-URL: http://www.inderscience.com/link.php?id=94850 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:332-349 Template-Type: ReDIF-Article 1.0 Author-Name: Shiva Zandkarimkhani Author-X-Name-First: Shiva Author-X-Name-Last: Zandkarimkhani Author-Name: Mohammad Mahdi Nasiri Author-X-Name-First: Mohammad Mahdi Author-X-Name-Last: Nasiri Author-Name: Jafar Heydari Author-X-Name-First: Jafar Author-X-Name-Last: Heydari Title: Designing an open-loop supply chain network for recyclable products: a case study Abstract: Recently, because of the recycling policies and environmental issues, the combination of forward and reverse logistics has attracted lots of attention to itself. The current paper presents a designed open-loop supply chain network to reuse the returned goods. To this aim, a mixed integer linear model is proposed that minimises the total cost. The proposed model determines the location of distribution centres, recycling centres, collection centres, disposal centres and also the quantity of the transferred product between levels. Finally, in order to investigate the effectiveness of the proposed model, it is implemented at one of Iranian Poly Ethylene Terephthalate (PET) product companies. Journal: Int. J. of Mathematics in Operational Research Pages: 350-364 Issue: 3 Volume: 13 Year: 2018 Keywords: supply chain management; mathematical programming; reverse logistics; open-loop supply chain. File-URL: http://www.inderscience.com/link.php?id=94851 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:350-364 Template-Type: ReDIF-Article 1.0 Author-Name: Mohammad M. Hamasha Author-X-Name-First: Mohammad M. Author-X-Name-Last: Hamasha Title: Generate random variates using a newly introduced approximation to cumulative density of lower truncated normal distribution for simulation applications Abstract: In this paper, the lower side truncated cumulative normal distribution is approximated by a simple function, the inverse of the function is derived, and random variates are explained how to be generated from the introduced inverse approximation. The introduced approximation is derived from Aludaat and Alodat's model of approximating cumulative normal distribution. The accuracy of the introduced function is investigated in term of maximum absolute error (i.e., 0.003944). This level of accuracy is possibly the best comparing all previous similar models to the best of the author's knowledge. Journal: Int. J. of Mathematics in Operational Research Pages: 365-376 Issue: 3 Volume: 13 Year: 2018 Keywords: normal distribution; random variate generation; density function; cumulative density function; lower truncated normal distribution; mathematical model; approximation; standard normal distribution; simulation; accuracy. File-URL: http://www.inderscience.com/link.php?id=94852 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:365-376 Template-Type: ReDIF-Article 1.0 Author-Name: Sofiane Ziani Author-X-Name-First: Sofiane Author-X-Name-Last: Ziani Author-Name: Fazia Rahmoune Author-X-Name-First: Fazia Author-X-Name-Last: Rahmoune Author-Name: Mohammed Said Radjef Author-X-Name-First: Mohammed Said Author-X-Name-Last: Radjef Title: Equilibrium behavioural strategies in an M/M/1 queue Abstract: For an <i>M</i>/<i>M</i>/1 system, we analyse the strategic interactions of the social optimiser, the service provider and customers and their consequences on the system. The social optimiser chooses the type of information to make available to customers (make the system observable or unobservable), the service provider chooses the service rate with which he performs the service, and customers decide, according to the strategic choices of the first two agents, to use or not the system. As these agents are interacting in a common environment with respect to their objectives, we model the problem as a three-stage game between them. A resolution of the different stages will be made, which will give the overall solution to the considered problem, corresponding to the subgame perfect Nash equilibrium in behavioural strategies. A numerical analysis will be made where one can see the graphical solution of the game, comparisons and interpretations will be well established. Journal: Int. J. of Mathematics in Operational Research Pages: 377-400 Issue: 3 Volume: 13 Year: 2018 Keywords: queueing; reward-cost structure; extensive form game; behavioural strategy; Nash equilibrium. File-URL: http://www.inderscience.com/link.php?id=94853 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:377-400 Template-Type: ReDIF-Article 1.0 Author-Name: Hossein Sayyadi Tooranloo Author-X-Name-First: Hossein Sayyadi Author-X-Name-Last: Tooranloo Author-Name: Arezoo Sadat Ayatollah Author-X-Name-First: Arezoo Sadat Author-X-Name-Last: Ayatollah Author-Name: Asiyeh Iranpour Author-X-Name-First: Asiyeh Author-X-Name-Last: Iranpour Title: A model for supplier evaluation and selection based on integrated interval-valued intuitionistic fuzzy AHP-TOPSIS approach Abstract: Today, the global market is confronted with short-lifecycle products or highly demanding customers that calls a lot of focus on supply chain. Among the activities of the supply chain, activities of effective purchasing are the most important activity to proper selection of suppliers since of supplier evaluation and selection problem is a multi-criteria decision-making problem that is along with high degree of ambiguity and uncertainty in the real world decision making. Since the information on real world decision-making are often imprecise and expressed verbally therefore the fuzzy sets theory can be effectively used to solve such problems. This paper first provides an overview on the supplier evaluation and selection problem, and then presents a decision making model that integrates interval-valued intuitionistic fuzzy AHP (IVIF-AHP) and interval-valued intuitionistic fuzzy TOPSIS (IVIF-TOPSIS) to solve such problems, and in the end, provides a numerical example to demonstrate the use of the proposed approach. Journal: Int. J. of Mathematics in Operational Research Pages: 401-417 Issue: 3 Volume: 13 Year: 2018 Keywords: supplier selection; analytic hierarchy process; AHP; TOPSIS; interval-valued intuitionistic fuzzy. File-URL: http://www.inderscience.com/link.php?id=94854 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:3:p:401-417 Template-Type: ReDIF-Article 1.0 Author-Name: Madhu Jain Author-X-Name-First: Madhu Author-X-Name-Last: Jain Author-Name: Ritu Gupta Author-X-Name-First: Ritu Author-X-Name-Last: Gupta Title: N-policy for redundant repairable system with multiple types of warm standbys with switching failure and vacation Abstract: This investigation is concerned with the reliability analysis of redundant repairable system which is supported by mixed standby and two repairmen who turn on according to a threshold N-policy. The first repairman never takes a vacation while the second repairman leaves for a vacation of random length when the number of failed components is less than N. The concepts of standby switching failure, degradation and common cause failure are incorporated to predict the performance metrics of the real time redundant repairable system. By developing Markov model, the transient queue size distribution and expressions for the system reliability, mean time to system failure and other performance measures are obtained. The sensitivity analysis is performed by taking numerical illustration. The model is also examined computationally by employing the adaptive network-based fuzzy interference system (ANFIS) approach to compute the system descriptors. Using supervised learning process, the comparison between the ANFIS results and analytical results are made. Journal: Int. J. of Mathematics in Operational Research Pages: 419-449 Issue: 4 Volume: 13 Year: 2018 Keywords: reliability; N-policy; standby switching failures; server vacation; neuro fuzzy technique. File-URL: http://www.inderscience.com/link.php?id=95484 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:419-449 Template-Type: ReDIF-Article 1.0 Author-Name: Jaouad Oudaani Author-X-Name-First: Jaouad Author-X-Name-Last: Oudaani Title: Numerical approach to the uniqueness solution of Von-Karman evolution Abstract: The purpose of this paper is to give some theoretical and numerical analysis approach, for local generalised and weakly uniqueness solution, to the models with interior dissipation and clamped boundary conditions of Von-Karman evolution, without rotational inertia and nonlinear internal dissipation. To approach the uniqueness solution we use the scheme of finite difference method. Journal: Int. J. of Mathematics in Operational Research Pages: 450-470 Issue: 4 Volume: 13 Year: 2018 Keywords: Von-Karman evolution; rotational inertia (α ≥ 0); finite difference method; non-coupled method. File-URL: http://www.inderscience.com/link.php?id=95485 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:450-470 Template-Type: ReDIF-Article 1.0 Author-Name: P.K. Kapur Author-X-Name-First: P.K. Author-X-Name-Last: Kapur Author-Name: Ompal Singh Author-X-Name-First: Ompal Author-X-Name-Last: Singh Author-Name: A.K. Shrivastava Author-X-Name-First: A.K. Author-X-Name-Last: Shrivastava Title: A unified approach for optimal release, patching and testing time of a software Abstract: The ever growing consumer's expectations for innovative and reliable software products within no time have driven developers to reframe the whole development process accordingly. To sustain in the stiff market competition, nowadays software firms are releasing their product early and continue testing to fix the remaining number of bugs in the operational phase by providing patches. A patch is a small program to fix the bugs. But continuing testing to provide patches for better product experience to users is also not economical from the firm's point of view. In the existing software reliability literature, few researchers have worked on to determine the optimal release and testing stop time of a software, but no work has been done to determine the optimal time for releasing, patching and to stop testing the software. In this paper, we present a unified framework of optimal policy to determine optimal software release time, patching time and testing stop time, to minimise overall testing cost. The proposed cost model is validated on a real life software failure dataset of tandem computers. Journal: Int. J. of Mathematics in Operational Research Pages: 471-491 Issue: 4 Volume: 13 Year: 2018 Keywords: modelling; patch; release; software reliability; software updating; software testing; unified approach. File-URL: http://www.inderscience.com/link.php?id=95486 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:471-491 Template-Type: ReDIF-Article 1.0 Author-Name: Ririn Diar Astanti Author-X-Name-First: Ririn Diar Author-X-Name-Last: Astanti Author-Name: Huynh Trung Luong Author-X-Name-First: Huynh Trung Author-X-Name-Last: Luong Author-Name: Hui Ming Wee Author-X-Name-First: Hui Ming Author-X-Name-Last: Wee Author-Name: The Jin Ai Author-X-Name-First: The Jin Author-X-Name-Last: Ai Title: A forward with backward inventory policy algorithm for nonlinear increasing demand and shortage backorders Abstract: The traditional inventory policies have been developed for constant demand processes. In reality, demand is not always stable; it might have an increasing pattern. In this paper, a forward with backward inventory policy algorithm is developed to determine the operational parameters of an inventory system with a nonlinear increasing demand rate, shortage backorders and a finite planning horizon. Numerical experiments are also conducted to compare the results with the existing techniques and to illustrate the applicability of the proposed technique. Journal: Int. J. of Mathematics in Operational Research Pages: 492-512 Issue: 4 Volume: 13 Year: 2018 Keywords: inventory; nonlinear increasing demand pattern; shortage backorders; forward with backward inventory policy algorithm. File-URL: http://www.inderscience.com/link.php?id=95487 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:492-512 Template-Type: ReDIF-Article 1.0 Author-Name: Ali Mohtashami Author-X-Name-First: Ali Author-X-Name-Last: Mohtashami Author-Name: Alireza Alinezhad Author-X-Name-First: Alireza Author-X-Name-Last: Alinezhad Author-Name: Mohammad Javad Nasiri Sadeghloo Author-X-Name-First: Mohammad Javad Nasiri Author-X-Name-Last: Sadeghloo Title: Measuring the productivity changes with double frontiers data envelopment analysis for two-stage processes Abstract: The purpose of this paper is to develop an output oriented methodology with constant return to scale (CRS) assumption for calculating productivity changes by using double frontier (optimistic and pessimistic) data envelopment analysis (DEA) simultaneously for two-stage processes. Measuring the productivity changes with Malmquist productivity index (MPI) via double frontiers DEA with single process has been defined by Wang and Lan (2011) as a geometrically average of optimistic and pessimistic point of views to generate an aggregate MPI. In order to develop and modify the previous studies, in this paper we have proposed a method to modify Wang and Lan (2011) aggregate MPI and also extend it to two-stage process which we refer to the double frontiers two-stage DEA (DFTDEA). It should be mentioned that the proposed model of this paper measures the MPI's distance functions for two individual stages and whole process for both DEA different points of view by the traditional DEA models and supposed relational models in output oriented CCR models, respectively. Therefore, the identified double frontiers two-stage DEA (DFTDEA-based MPI) is more realistic and comprehensive than the conventional optimistic or pessimistic DEA-based MPI individually. Subsequently, the proposed approach is examined to five Iranian commercial banks over the five-year period, 2009-2013. Journal: Int. J. of Mathematics in Operational Research Pages: 513-532 Issue: 4 Volume: 13 Year: 2018 Keywords: data envelopment analysis; DEA; two-stage; double frontier; Malmquist productivity index. File-URL: http://www.inderscience.com/link.php?id=95488 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:513-532 Template-Type: ReDIF-Article 1.0 Author-Name: Brojeswar Pal Author-X-Name-First: Brojeswar Author-X-Name-Last: Pal Author-Name: Asoke Kumar Bhunia Author-X-Name-First: Asoke Kumar Author-X-Name-Last: Bhunia Author-Name: Kripasindhu Chaudhuri Author-X-Name-First: Kripasindhu Author-X-Name-Last: Chaudhuri Title: Promotional effort and quality sensitive two echelon production inventory model with partial backlogging Abstract: This study deals with the modelling aspect of a two echelon imperfect production system in the presence of the promotional effort of the retailer. The production cost of the system varies with both the ordering lot size and quality of product, and the demand of the product depends on the quality of the product. The inventory level for the manufacturer starts with shortages and new production and the inventory level for the retailer also begin with shortages and new product lot. The cycle ends for both the players with also backlogged inventory. The backlogging rate for each of the player is dependent on waiting time. The behaviour of the model under integrated system is analysed. In the decentralised structure, retailer Stackelberg model are also discussed. The sensitivity of the key parameters is examined to test feasibility of the model. Finally, a numerical example is provided to investigate the proposed model. Journal: Int. J. of Mathematics in Operational Research Pages: 533-547 Issue: 4 Volume: 13 Year: 2018 Keywords: imperfect production inventory model; promotional effort; quality; partially backlogging. File-URL: http://www.inderscience.com/link.php?id=95492 File-Format: text/html File-Restriction: Access to full text is restricted to subscribers. Handle: RePEc:ids:ijmore:v:13:y:2018:i:4:p:533-547