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Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system

Year 2023, Volume: 52 Issue: 5, 1438 - 1460, 31.10.2023
https://doi.org/10.15672/hujms.1183966

Abstract

Consider a single-server retrial queueing system with non-preemptive priority service, where customers arrive in a Poisson process with a rate of $\lambda_1$ for high-priority customers (class 1) and $\lambda_2$ for low-priority customers (class 2). If a high-priority customer is blocked, they are queued, while a low-priority customer must leave the service area and return after some random period of time to try again. In contrast with existing literature, we assume different service time distributions for the two customer classes. This investigation proposes a stochastic comparison method based on the general theory of stochastic orders to obtain lower and upper bounds for the joint stationary distribution of the number of customers at departure epochs in the considered model. Specifically, we discuss the stochastic monotonicity of the embedded Markov queue-length process in terms of both the usual stochastic and convex orders. We also perform a numerical sensitivity analysis to study the effect of the arrival rate of high-priority customers on system performance measures.

References

  • [1] L.M. Alem, M. Boualem and D. Aïssani, Stochastic comparison bounds for M1,M2/G1,G2/1 retrial queue with two way communication, Hacet. J. Math. Stat. 48 (4), 1185–1200, 2019.
  • [2] L.M. Alem, M. Boualem and D. Aïssani, Bounds of the stationary distribution in M/G/1 retrial queue with two-way communication and n types of outgoing calls, Yugosl. J. Oper. Res. 29 (3), 375–391, 2019.
  • [3] S.I. Ammar and P. Rajadurai, Performance analysis of preemptive priority retrial queueing system with disaster under working breakdown services, Symmetry 11 (3), 1–15, 2019.
  • [4] J.R. Artalejo and A. Gómez-Corral, Retrial Queueing System: A Computational Approach, Springer, Berlin, 2008.
  • [5] I. Atencia, M.Á. Galán-García, G. Aguilera-Venegas and J.L. Galán-García, A non markovian retrial queueing system, J. Comput. Appl. Math. 431, 1-13, 2023.
  • [6] A. Bhagat, Unreliable priority retrial queues with double orbits and discouraged customers, AIP Conf. Proc. 2214 (1), 020014, 2020.
  • [7] M. Boualem, Insensitive bounds for the stationary distribution of a single server retrial queue with server subject to active breakdowns, Adv. Oper. Res., Doi: 10.1155/2014/985453, 2014.
  • [8] M. Boualem, Stochastic analysis of a single server unreliable queue with balking and general retrial time, Discrete Contin. Models Appl. Comput. 28 (4), 319–326, 2020.
  • [9] M. Boualem, A. Bareche and M. Cherfaoui, Approximate controllability of stochastic bounds of stationary distribution of an M/G/1 queue with repeated attempts and twophase service, Int. J. Manag. Sci. Eng. Manag. 14 (2), 79–85, 2019.
  • [10] M. Boualem, M. Cherfaoui and D. Aïssani, Monotonicity properties for a single server queue with classical retrial policy and service interruptions, Proc. Jangjeon Math. Soc. 19 (2), 225–236, 2016.
  • [11] M. Boualem, M. Cherfaoui, N. Djellab and D. Aïssani, A stochastic version analysis of an M/G/1 retrial queue with Bernoulli schedule, Bull. Iranian Math. Soc. 43 (5), 1377–1397, 2017.
  • [12] M. Boualem, M. Cherfaoui, N. Djellab and D. Aïssani, Inégalités stochastiques pour le modèle d’attente M/G/1/1 avec rappels, Afr. Mat. 28 (5-6), 851–868, 2017.
  • [13] M. Boualem, N. Djellab and D. Aïssani, Stochastic inequalities for M/G/1 retrial queues with vacations and constant retrial policy, Math. Comput. Model. 50 (1-2), 207–212, 2009.
  • [14] M. Boualem, N. Djellab and D. Aïssani, Stochastic bounds for a single server queue with general retrial times, Bull. Iranian Math. Soc. 40 (1), 183–198, 2014.
  • [15] M. Boualem, N. Djellab and D. Aïssani, Stochastic approximations and monotonicity of a single server feedback retrial queue, Math. Probl. Eng., Doi: 10.1155/2012/536982, 2012.
  • [16] M. Boualem and N. Touche, Stochastic monotonicity approach for a non-Markovian priority retrial queue, Asian-Eur. J. Math. 14 (09), 1-8, 2021.
  • [17] A. Bušić and J.M. Fourneau, Monotonicity and performance evaluation: Applications to high speed and mobile networks, Clust. Comput. 15, 401–414, 2012.
  • [18] B.D. Choi and Y. Chang, Single server retrial queues with priority calls, Math. Comput. Model. 30 (3–4), 7–32, 1999.
  • [19] C. D’Apice, A. Dudin, S. Dudin and R. Manzo, Priority queueing system with many types of requests and restricted processor sharing, J. Ambient Intell. Humaniz. Comput. 14, 12651–12662, 2023.
  • [20] A. Devos, J. Walraevens, T. Phung-Duc and H. Bruneel, Analysis of the queue lengths in a priority retrial queue with constant retrial policy, J. Ind. Manag. Optim. 16 (6), 2813–2842, 2020.
  • [21] I. Dimitriou, A single server retrial queue with event-dependent arrival rates, Ann. Oper. Res., Doi: 10.1007/s10479-023-05263-z, 2023.
  • [22] A.N. Dudin, M.H. Lee, O. Dudina and S.K. Lee, Analysis of priority retrial queue with many types of customers and servers reservation as a model of cognitive radio system, IEEE Trans. Commun. 65 (1), 186–199, 2017.
  • [23] G.I. Falin, A survey of retrial queues, Queueing Syst. 7, 127–168, 1990.
  • [24] G.I. Falin, J.R. Artalejo and M. Martin, On the single server retrial queue with priority customers, Queueing Syst. 14, 439–455, 1993.
  • [25] G.I. Falin, and J.G.C. Templeton, Retrial Queues, Chapman and Hall, London, 1997.
  • [26] D. Fiems, Retrial queues with constant retrial times, Queueing Syst. 103, 347–365 2023.
  • [27] W. Fong-Fan, An efficient optimization procedure for location-inventory problems with (S−1, S) policy and retrial demands, Math. Comput. Simulation 206, 664–688, 2023.
  • [28] S. Gao, A preemptive priority retrial queue with two classes of customers and general retrial times, Oper. Res. Int. J. 15 (2), 233–251, 2015.
  • [29] M. Jain and S.S. Sanga, Unreliable single server double orbit retrial queue with balking, Proc. Nat. Acad. Sci. India Sect. A 91, 257–268, 2021.
  • [30] K. Kim, M/G/1 preemptive priority queues with finite and infinite buffers, J. Soc. Korea Ind. Syst. 43 (4), 1–14, 2020.
  • [31] K. Kim, (N, n)-preemptive-priority M/G/1 queues with finite and infinite buffers, J. Appl. Math., Doi: 10.1155/2022/5834258, 2022.
  • [32] K. Kim, Finite-buffer M/G/1 queues with time and space priorities, Math. Probl. Eng., Doi: 10.1155/2022/4539940, 2022.
  • [33] B.K. Kumar, R. Sankar, R.N. Krishnan and R. Rukmani, Performance analysis of multi-processor two-stage tandem call center retrial queues with non-reliable processors, Methodol. Comput. Appl. Probab. 24, 95–142, 2022.
  • [34] H.M. Liang and V.G. Kulkarni, Monotonicity properties of single server retrial queues, Stoch. Models 9 (3), 373–400, 1993.
  • [35] W.A. Massey, Stochastic orderings for Markov processes on partially ordered spaces, Math. Oper. Res. 12 (2), 350–367, 1987.
  • [36] A.V. Mistryukov and V.G. Ushakov, Ergodicity of two class priority queues with preemptive priority, J. Math. Sci. 267, 255–259, 2022.
  • [37] L. Mokdad and H. Castel-Taleb, Stochastic comparisons: A methodology for the performance evaluation of fixed and mobile networks, Comput. Commun. 31 (17), 3894– 3904, 2008.
  • [38] A. Müller and D. Stoyan, Comparison Methods for Stochastic Models and Risk, John Wiley and Sons, 2002.
  • [39] R. Nekrasova, E. Morozov, D. Efrosinin and S. Natalia, Stability analysis of a twoclass system with constant retrial rate and unreliable server, Ann. Oper. Res., Doi: 10.1007/s10479-023-05216-6, 2023.
  • [40] T. Phung-Duc, K. Akutsu, K. Kawanishi, O. Salameh and S. Wittevrongel, Queueing models for cognitive wireless networks with sensing time of secondary users, Ann. Oper. Res. 310 (2), 641–660, 2022.
  • [41] R. Raj and V. Jain, Optimization of traffic control in MMAP[2]/PH[2]/S priority queueing model with PH retrial times and the preemptive repeat policy, J. Ind. Manag. Optim. 19 (4), 2333–2353, 2023.
  • [42] S.S. Sanga and M. Jain, Cost optimization and ANFIS computing for admission control of M/M/1/K queue with general retrial times and discouragement, Appl. Math. Comput. 363, 1-22, 2019.
  • [43] A.K. Subramanian, U. Ghosh, S. Ramaswamy, W.S. Alnumay and P.K. Sharma, PrEEMAC: Priority based energy efficient MAC protocol for Wireless Body Sensor Networks, Sustain. Comput.: Inform. Syst. 30, 1-9, 2021.
  • [44] K. Sun, Y. Liu and K. Li, Energy harvesting cognitive radio networks with strategic users: A two-class queueing model with retrials, Comput. Commun. 199, 98–112, 2023.
  • [45] M. Sundararaman, D. Narasimhan and I.A. Sherif, Reliability and optimization measures of retrial queue with different classes of customers under a working vacation schedule, Discrete Dyn. Nat. Soc., Doi: 10.1155/2022/6806104, 2022.
  • [46] L. Suoping, X. Qianyu, G. Jaafar and Y. Nana, Modeling and performance analysis of channel assembling based on Ps-rc strategy with priority queues in CRNs, Wirel. Commun. Mob. Comput., Doi: 10.1155/2022/6384261, 2022.
  • [47] R. Szekli, Stochastic Ordering and Dependence in Applied Probability, Springer, New York, 1995.
  • [48] I.M. Verloop, U. Ayesta and S. Borst, Monotonicity properties for multi-class queueing systems, Discrete Event Dyn. Syst. 20, 473–509, 2010.
  • [49] J. Xu, L. Liu and K. Wu, Analysis of a retrial queueing system with priority service and modified multiple vacations, Comm. Statist. Theory Methods 52 (17), 6207–6231, 2023.
  • [50] T. Yang and J.G.C. Templeton, A survey on retrial queues, Queueing Syst. 2, 201– 233, 1997.
  • [51] S. Yuvarani and M.C. Saravanarajan, Analysis of a preemptive priority retrial queue with negative customers, starting failure and at most J vacations, Int. J. of Knowledge Management in Tourism and Hospitality 1 (1), 76–109, 2017.
  • [52] Y. Zhang and J. Wang, Effectiveness, fairness and social welfare maximization: service rules for the interrupted secondary users in cognitive radio networks, Ann. Oper. Res. 323, 247–286, 2023.
  • [53] D. Zirem, M. Boualem, K. Adel-Aissanou and D. Aïssani, Analysis of a single server batch arrival unreliable queue with balking and general retrial time, Qual. Technol. Quant. Manag. 16 (6), 672–695, 2019.
Year 2023, Volume: 52 Issue: 5, 1438 - 1460, 31.10.2023
https://doi.org/10.15672/hujms.1183966

Abstract

References

  • [1] L.M. Alem, M. Boualem and D. Aïssani, Stochastic comparison bounds for M1,M2/G1,G2/1 retrial queue with two way communication, Hacet. J. Math. Stat. 48 (4), 1185–1200, 2019.
  • [2] L.M. Alem, M. Boualem and D. Aïssani, Bounds of the stationary distribution in M/G/1 retrial queue with two-way communication and n types of outgoing calls, Yugosl. J. Oper. Res. 29 (3), 375–391, 2019.
  • [3] S.I. Ammar and P. Rajadurai, Performance analysis of preemptive priority retrial queueing system with disaster under working breakdown services, Symmetry 11 (3), 1–15, 2019.
  • [4] J.R. Artalejo and A. Gómez-Corral, Retrial Queueing System: A Computational Approach, Springer, Berlin, 2008.
  • [5] I. Atencia, M.Á. Galán-García, G. Aguilera-Venegas and J.L. Galán-García, A non markovian retrial queueing system, J. Comput. Appl. Math. 431, 1-13, 2023.
  • [6] A. Bhagat, Unreliable priority retrial queues with double orbits and discouraged customers, AIP Conf. Proc. 2214 (1), 020014, 2020.
  • [7] M. Boualem, Insensitive bounds for the stationary distribution of a single server retrial queue with server subject to active breakdowns, Adv. Oper. Res., Doi: 10.1155/2014/985453, 2014.
  • [8] M. Boualem, Stochastic analysis of a single server unreliable queue with balking and general retrial time, Discrete Contin. Models Appl. Comput. 28 (4), 319–326, 2020.
  • [9] M. Boualem, A. Bareche and M. Cherfaoui, Approximate controllability of stochastic bounds of stationary distribution of an M/G/1 queue with repeated attempts and twophase service, Int. J. Manag. Sci. Eng. Manag. 14 (2), 79–85, 2019.
  • [10] M. Boualem, M. Cherfaoui and D. Aïssani, Monotonicity properties for a single server queue with classical retrial policy and service interruptions, Proc. Jangjeon Math. Soc. 19 (2), 225–236, 2016.
  • [11] M. Boualem, M. Cherfaoui, N. Djellab and D. Aïssani, A stochastic version analysis of an M/G/1 retrial queue with Bernoulli schedule, Bull. Iranian Math. Soc. 43 (5), 1377–1397, 2017.
  • [12] M. Boualem, M. Cherfaoui, N. Djellab and D. Aïssani, Inégalités stochastiques pour le modèle d’attente M/G/1/1 avec rappels, Afr. Mat. 28 (5-6), 851–868, 2017.
  • [13] M. Boualem, N. Djellab and D. Aïssani, Stochastic inequalities for M/G/1 retrial queues with vacations and constant retrial policy, Math. Comput. Model. 50 (1-2), 207–212, 2009.
  • [14] M. Boualem, N. Djellab and D. Aïssani, Stochastic bounds for a single server queue with general retrial times, Bull. Iranian Math. Soc. 40 (1), 183–198, 2014.
  • [15] M. Boualem, N. Djellab and D. Aïssani, Stochastic approximations and monotonicity of a single server feedback retrial queue, Math. Probl. Eng., Doi: 10.1155/2012/536982, 2012.
  • [16] M. Boualem and N. Touche, Stochastic monotonicity approach for a non-Markovian priority retrial queue, Asian-Eur. J. Math. 14 (09), 1-8, 2021.
  • [17] A. Bušić and J.M. Fourneau, Monotonicity and performance evaluation: Applications to high speed and mobile networks, Clust. Comput. 15, 401–414, 2012.
  • [18] B.D. Choi and Y. Chang, Single server retrial queues with priority calls, Math. Comput. Model. 30 (3–4), 7–32, 1999.
  • [19] C. D’Apice, A. Dudin, S. Dudin and R. Manzo, Priority queueing system with many types of requests and restricted processor sharing, J. Ambient Intell. Humaniz. Comput. 14, 12651–12662, 2023.
  • [20] A. Devos, J. Walraevens, T. Phung-Duc and H. Bruneel, Analysis of the queue lengths in a priority retrial queue with constant retrial policy, J. Ind. Manag. Optim. 16 (6), 2813–2842, 2020.
  • [21] I. Dimitriou, A single server retrial queue with event-dependent arrival rates, Ann. Oper. Res., Doi: 10.1007/s10479-023-05263-z, 2023.
  • [22] A.N. Dudin, M.H. Lee, O. Dudina and S.K. Lee, Analysis of priority retrial queue with many types of customers and servers reservation as a model of cognitive radio system, IEEE Trans. Commun. 65 (1), 186–199, 2017.
  • [23] G.I. Falin, A survey of retrial queues, Queueing Syst. 7, 127–168, 1990.
  • [24] G.I. Falin, J.R. Artalejo and M. Martin, On the single server retrial queue with priority customers, Queueing Syst. 14, 439–455, 1993.
  • [25] G.I. Falin, and J.G.C. Templeton, Retrial Queues, Chapman and Hall, London, 1997.
  • [26] D. Fiems, Retrial queues with constant retrial times, Queueing Syst. 103, 347–365 2023.
  • [27] W. Fong-Fan, An efficient optimization procedure for location-inventory problems with (S−1, S) policy and retrial demands, Math. Comput. Simulation 206, 664–688, 2023.
  • [28] S. Gao, A preemptive priority retrial queue with two classes of customers and general retrial times, Oper. Res. Int. J. 15 (2), 233–251, 2015.
  • [29] M. Jain and S.S. Sanga, Unreliable single server double orbit retrial queue with balking, Proc. Nat. Acad. Sci. India Sect. A 91, 257–268, 2021.
  • [30] K. Kim, M/G/1 preemptive priority queues with finite and infinite buffers, J. Soc. Korea Ind. Syst. 43 (4), 1–14, 2020.
  • [31] K. Kim, (N, n)-preemptive-priority M/G/1 queues with finite and infinite buffers, J. Appl. Math., Doi: 10.1155/2022/5834258, 2022.
  • [32] K. Kim, Finite-buffer M/G/1 queues with time and space priorities, Math. Probl. Eng., Doi: 10.1155/2022/4539940, 2022.
  • [33] B.K. Kumar, R. Sankar, R.N. Krishnan and R. Rukmani, Performance analysis of multi-processor two-stage tandem call center retrial queues with non-reliable processors, Methodol. Comput. Appl. Probab. 24, 95–142, 2022.
  • [34] H.M. Liang and V.G. Kulkarni, Monotonicity properties of single server retrial queues, Stoch. Models 9 (3), 373–400, 1993.
  • [35] W.A. Massey, Stochastic orderings for Markov processes on partially ordered spaces, Math. Oper. Res. 12 (2), 350–367, 1987.
  • [36] A.V. Mistryukov and V.G. Ushakov, Ergodicity of two class priority queues with preemptive priority, J. Math. Sci. 267, 255–259, 2022.
  • [37] L. Mokdad and H. Castel-Taleb, Stochastic comparisons: A methodology for the performance evaluation of fixed and mobile networks, Comput. Commun. 31 (17), 3894– 3904, 2008.
  • [38] A. Müller and D. Stoyan, Comparison Methods for Stochastic Models and Risk, John Wiley and Sons, 2002.
  • [39] R. Nekrasova, E. Morozov, D. Efrosinin and S. Natalia, Stability analysis of a twoclass system with constant retrial rate and unreliable server, Ann. Oper. Res., Doi: 10.1007/s10479-023-05216-6, 2023.
  • [40] T. Phung-Duc, K. Akutsu, K. Kawanishi, O. Salameh and S. Wittevrongel, Queueing models for cognitive wireless networks with sensing time of secondary users, Ann. Oper. Res. 310 (2), 641–660, 2022.
  • [41] R. Raj and V. Jain, Optimization of traffic control in MMAP[2]/PH[2]/S priority queueing model with PH retrial times and the preemptive repeat policy, J. Ind. Manag. Optim. 19 (4), 2333–2353, 2023.
  • [42] S.S. Sanga and M. Jain, Cost optimization and ANFIS computing for admission control of M/M/1/K queue with general retrial times and discouragement, Appl. Math. Comput. 363, 1-22, 2019.
  • [43] A.K. Subramanian, U. Ghosh, S. Ramaswamy, W.S. Alnumay and P.K. Sharma, PrEEMAC: Priority based energy efficient MAC protocol for Wireless Body Sensor Networks, Sustain. Comput.: Inform. Syst. 30, 1-9, 2021.
  • [44] K. Sun, Y. Liu and K. Li, Energy harvesting cognitive radio networks with strategic users: A two-class queueing model with retrials, Comput. Commun. 199, 98–112, 2023.
  • [45] M. Sundararaman, D. Narasimhan and I.A. Sherif, Reliability and optimization measures of retrial queue with different classes of customers under a working vacation schedule, Discrete Dyn. Nat. Soc., Doi: 10.1155/2022/6806104, 2022.
  • [46] L. Suoping, X. Qianyu, G. Jaafar and Y. Nana, Modeling and performance analysis of channel assembling based on Ps-rc strategy with priority queues in CRNs, Wirel. Commun. Mob. Comput., Doi: 10.1155/2022/6384261, 2022.
  • [47] R. Szekli, Stochastic Ordering and Dependence in Applied Probability, Springer, New York, 1995.
  • [48] I.M. Verloop, U. Ayesta and S. Borst, Monotonicity properties for multi-class queueing systems, Discrete Event Dyn. Syst. 20, 473–509, 2010.
  • [49] J. Xu, L. Liu and K. Wu, Analysis of a retrial queueing system with priority service and modified multiple vacations, Comm. Statist. Theory Methods 52 (17), 6207–6231, 2023.
  • [50] T. Yang and J.G.C. Templeton, A survey on retrial queues, Queueing Syst. 2, 201– 233, 1997.
  • [51] S. Yuvarani and M.C. Saravanarajan, Analysis of a preemptive priority retrial queue with negative customers, starting failure and at most J vacations, Int. J. of Knowledge Management in Tourism and Hospitality 1 (1), 76–109, 2017.
  • [52] Y. Zhang and J. Wang, Effectiveness, fairness and social welfare maximization: service rules for the interrupted secondary users in cognitive radio networks, Ann. Oper. Res. 323, 247–286, 2023.
  • [53] D. Zirem, M. Boualem, K. Adel-Aissanou and D. Aïssani, Analysis of a single server batch arrival unreliable queue with balking and general retrial time, Qual. Technol. Quant. Manag. 16 (6), 672–695, 2019.
There are 53 citations in total.

Details

Primary Language English
Subjects Statistics
Journal Section Statistics
Authors

Houria Hablal This is me 0000-0002-2921-0146

Nassim Touche 0000-0002-9185-3433

Lalamaghnia Alem This is me 0000-0002-8858-7381

Amina Angelika Bouchentouf 0000-0001-8972-4221

Mohamed Boualem This is me 0000-0001-9414-714X

Early Pub Date August 9, 2023
Publication Date October 31, 2023
Published in Issue Year 2023 Volume: 52 Issue: 5

Cite

APA Hablal, H., Touche, N., Alem, L., Bouchentouf, A. A., et al. (2023). Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system. Hacettepe Journal of Mathematics and Statistics, 52(5), 1438-1460. https://doi.org/10.15672/hujms.1183966
AMA Hablal H, Touche N, Alem L, Bouchentouf AA, Boualem M. Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system. Hacettepe Journal of Mathematics and Statistics. October 2023;52(5):1438-1460. doi:10.15672/hujms.1183966
Chicago Hablal, Houria, Nassim Touche, Lalamaghnia Alem, Amina Angelika Bouchentouf, and Mohamed Boualem. “Lower and Upper Stochastic Bounds for the Joint Stationary Distribution of a Non-Preemptive Priority Retrial Queueing System”. Hacettepe Journal of Mathematics and Statistics 52, no. 5 (October 2023): 1438-60. https://doi.org/10.15672/hujms.1183966.
EndNote Hablal H, Touche N, Alem L, Bouchentouf AA, Boualem M (October 1, 2023) Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system. Hacettepe Journal of Mathematics and Statistics 52 5 1438–1460.
IEEE H. Hablal, N. Touche, L. Alem, A. A. Bouchentouf, and M. Boualem, “Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system”, Hacettepe Journal of Mathematics and Statistics, vol. 52, no. 5, pp. 1438–1460, 2023, doi: 10.15672/hujms.1183966.
ISNAD Hablal, Houria et al. “Lower and Upper Stochastic Bounds for the Joint Stationary Distribution of a Non-Preemptive Priority Retrial Queueing System”. Hacettepe Journal of Mathematics and Statistics 52/5 (October 2023), 1438-1460. https://doi.org/10.15672/hujms.1183966.
JAMA Hablal H, Touche N, Alem L, Bouchentouf AA, Boualem M. Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system. Hacettepe Journal of Mathematics and Statistics. 2023;52:1438–1460.
MLA Hablal, Houria et al. “Lower and Upper Stochastic Bounds for the Joint Stationary Distribution of a Non-Preemptive Priority Retrial Queueing System”. Hacettepe Journal of Mathematics and Statistics, vol. 52, no. 5, 2023, pp. 1438-60, doi:10.15672/hujms.1183966.
Vancouver Hablal H, Touche N, Alem L, Bouchentouf AA, Boualem M. Lower and upper stochastic bounds for the joint stationary distribution of a non-preemptive priority retrial queueing system. Hacettepe Journal of Mathematics and Statistics. 2023;52(5):1438-60.