@inproceedings{MTMT:34758809,
	title = {The Simulation of Finite-Source Retrial Queues with Two-Way Communication to the Orbit, Incorporating a Backup Server},
	url = {https://m2.mtmt.hu/api/publication/34758809},
	author = {Tóth, Ádám and Sztrik, János},
	booktitle = {Distributed Computer and Communication Networks: Control, Computation, Communications},
	doi = {10.1007/978-3-031-50482-2_4},
	unique-id = {34758809},
	year = {2024},
	pages = {44-55}
}

@article{MTMT:34748505,
	title = {Queuing-Inventory System with Catastrophes in the Warehouse: Case of Rare Catastrophes},
	url = {https://m2.mtmt.hu/api/publication/34748505},
	author = {Melikov, Agassi and Poladova, Laman and Sztrik, János},
	doi = {10.3390/math12060906},
	journal-iso = {MATHEMATICS-BASEL},
	journal = {MATHEMATICS},
	volume = {12},
	unique-id = {34748505},
	abstract = {A model of a single-server queuing-inventory system (QIS) with a limited waiting buffer for consumer customers (c-customers) and catastrophes has been developed. When a catastrophe occurs, all items in the system’s warehouse are destroyed, but c-customers in the system are still waiting for replenishment. In addition to c-customers, negative customers (n-customers) are also taken into account, each of which displaces one c-customer (if any). The policy (s, S) is used to replenish stocks. If, when a customer enters, the system warehouse is empty, then, according to Bernoulli’s trials, this customer either leaves the system without goods or joins the buffer. The mathematical model of the investigated QIS is constructed in the form of a continuous-time Markov chain (CTMC). Both exact and approximate methods for calculating the steady-state probabilities of constructed CTMCs are proposed and closed-form expressions are obtained for calculating the performance measures. Numerical evaluations are presented, demonstrating the high accuracy of the developed approximate formulas, as well as the behavior of performance measures depending on the input parameters. In addition, an optimization problem is solved to obtain the optimal value of the reorder point to minimize the expected total cost.},
	year = {2024},
	eissn = {2227-7390},
	pages = {906},
	orcid-numbers = {Melikov, Agassi/0000-0003-3721-7820; Poladova, Laman/0009-0001-3563-3292}
}

@article{MTMT:34748999,
	title = {Simulation of two-way communication retrial queueing systems with unreliable server and impatient customers in the orbit},
	url = {https://m2.mtmt.hu/api/publication/34748999},
	author = {Tóth, Ádám and Sztrik, János},
	journal-iso = {Stochastic Modeling and Applied Research of Technology},
	journal = {Stochastic Modeling and Applied Research of Technology},
	volume = {3},
	unique-id = {34748999},
	year = {2023},
	eissn = {2782-4705},
	pages = {45-50}
}

@CONFERENCE{MTMT:34446612,
	title = {Simulating retrial queues with a finite source, two-way communication to the orbit, the inclusion of a backup server and impatient customers},
	url = {https://m2.mtmt.hu/api/publication/34446612},
	author = {Tóth, Ádám and Sztrik, János and A., Bradvelidze},
	booktitle = {Proceedings of the 22th International Conference named after A.F. Terpugov, Informational Technologies and Mathematical Modelling ITMM-2023 Part 1.},
	unique-id = {34446612},
	year = {2023},
	pages = {59-64}
}

@article{MTMT:34412202,
	title = {Queueing-Inventory Systems with Catastrophes under Various Replenishment Policies},
	url = {https://m2.mtmt.hu/api/publication/34412202},
	author = {Ozkar, Serife and Melikov, Agassi and Sztrik, János},
	doi = {10.3390/math11234854},
	journal-iso = {MATHEMATICS-BASEL},
	journal = {MATHEMATICS},
	volume = {11},
	unique-id = {34412202},
	abstract = {We discuss two queueing-inventory systems with catastrophes in the warehouse. Catastrophes occur according to the Poisson process and instantly destroy all items in the inventory. The arrivals of the consumer customers follow a Markovian arrival process and they can be queued in an infinite buffer. The service time of a consumer customer follows a phase-type distribution. The system receives negative customers which have Poisson flows and as soon as a negative customer comes into the system, he causes a consumer customer to leave the system, if any. One of two inventory policies is used in the systems: either (s,S) or (s,Q). If the inventory level is zero when a consumer customer arrives, then this customer is either lost (lost sale) or joins the queue (backorder sale). The system is formulated by a four-dimensional continuous-time Markov chain. Ergodicity condition for both systems is established and steady-state distribution is obtained using the matrix-geometric method. By numerical studies, the influence of the distributions of the arrival process and the service time and the system parameters on performance measures are deeply analyzed. Finally, an optimization study is presented in which the criterion is the minimization of expected total costs and the controlled parameter is warehouse capacity.},
	year = {2023},
	eissn = {2227-7390},
	pages = {1-24},
	orcid-numbers = {Ozkar, Serife/0000-0003-3475-5666; Melikov, Agassi/0000-0003-3721-7820}
}

@article{MTMT:34397930,
	title = {Analysis of retrial queueing systems with two-way communication and impatient customers using simulation},
	url = {https://m2.mtmt.hu/api/publication/34397930},
	author = {Tóth, Ádám and Sztrik, János},
	doi = {10.33039/ami.2023.08.015},
	journal-iso = {ANN MATH INFORM},
	journal = {ANNALES MATHEMATICAE ET INFORMATICAE},
	volume = {58},
	unique-id = {34397930},
	issn = {1787-5021},
	year = {2023},
	eissn = {1787-6117},
	pages = {160-169}
}

@article{MTMT:34281828,
	title = {Modeling of Junior Servers Approaching a Senior Server in the Retrial Queuing-Inventory System},
	url = {https://m2.mtmt.hu/api/publication/34281828},
	author = {Jeganathan, Kathirvel and Harikrishnan, Thanushkodi and Lakshmanan, Kumarasankaralingam and Melikov, Agassi and Sztrik, János},
	doi = {10.3390/math11224581},
	journal-iso = {MATHEMATICS-BASEL},
	journal = {MATHEMATICS},
	volume = {11},
	unique-id = {34281828},
	abstract = {This article deals with the queuing-inventory system, composed of c junior servers, a senior server, two finite waiting halls, and an infinite orbit. On occasion, junior servers encounter challenges during customer service. In these instances, they approach the senior server for guidance in resolving the issue. Suppose the senior server is engaged with another junior server. The approaching junior servers await their turn in a finite waiting area with a capacity of c for consultation. Concerning this, we study the performance of junior servers approaching the senior server in the retrial queuing-inventory model with the two finite waiting halls dedicated to the primary customers and the junior servers for consultation. We formulate a level-dependent QBD process and solve its steady-state probability vector using Neuts and Rao’s truncation method. The stability condition of the system is derived and the R matrix is computed. The optimum total cost has been obtained, and the sensitivity analyses, which include the expected total cost, the waiting time of customers in the waiting hall and orbit, the number of busy servers, and a fraction of the successful retrial rate of the model, are computed numerically.},
	year = {2023},
	eissn = {2227-7390},
	pages = {1-31},
	orcid-numbers = {Jeganathan, Kathirvel/0000-0001-5546-1558; Harikrishnan, Thanushkodi/0000-0002-0270-9449; Melikov, Agassi/0000-0003-3721-7820}
}

@misc{MTMT:34196192,
	title = {Teaching Queueing Theory Based on Digital Technologies},
	url = {https://m2.mtmt.hu/api/publication/34196192},
	author = {Sztrik, János},
	unique-id = {34196192},
	year = {2023}
}

@misc{MTMT:34161084,
	title = {The simulation of finite-source retrial queues with two-way communication to the orbit using a backup server},
	url = {https://m2.mtmt.hu/api/publication/34161084},
	author = {Sztrik, János and Tóth, Ádám},
	unique-id = {34161084},
	year = {2023}
}

@article{MTMT:34149269,
	title = {Robustness of the cμ-Rule for an Unreliable Single-Server Two-Class Queueing System with Constant Retrial Rates},
	url = {https://m2.mtmt.hu/api/publication/34149269},
	author = {Efrosinin, Dmitry and Stepanova, Natalia and Sztrik, János},
	doi = {10.3390/math11184002},
	journal-iso = {MATHEMATICS-BASEL},
	journal = {MATHEMATICS},
	volume = {11},
	unique-id = {34149269},
	abstract = {We study the robustness of the cμ-rule for the optimal allocation of a resource consisting of one unreliable server to parallel queues with two different classes of customers. The customers in queues can be served with respect to a FIFO retrial discipline, when the customers at the heads of queues repeatedly try to occupy the server at a random time. It is proved that for scheduling problems in the system without arrivals, the cμ-rule minimizes the total average cost. For the system with arrivals, it is difficult directly to prove the optimality of the same policy with explicit relations. We derived for an infinite-buffer model a static control policy that also prescribes the service for certain values of system parameters exclusively for the class-i customers if both of the queues are not empty, with the aim to minimize the average cost per unit of time. It is also shown that in a finite buffer case, the cμ-rule fails.},
	year = {2023},
	eissn = {2227-7390},
	pages = {1-14},
	orcid-numbers = {Efrosinin, Dmitry/0000-0002-0902-6640}
}