The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Bhaskar Sengupta - One of the best experts on this subject based on the ideXlab platform.
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queue length distribution for the discriminatory processor sharing queue
Operations Research, 1996Co-Authors: Kiran M Rege, Bhaskar SenguptaAbstract:In this paper, we study a multiple class discriminatory processor-sharing queue. The queue is assumed to have Poisson input and exponentially Distributed Service times. In this discipline there are K classes of customers. When there are ni customers present in the system of class ii = 1, ', K, each member of class j receives a fraction of the server's capacity given by αj/âi=1Kniαi. Thus, associated with class i customers is a weight αi which determines the level of Service discrimination. For this problem, we find the moments of the queue-length distribution as a solution of linear simultaneous equations. We also prove a heavy traffic limit theorem for the joint queue-length distribution for this queue.
R Nuoezqueija - One of the best experts on this subject based on the ideXlab platform.
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heavy traffic analysis of a multiple phase network with discriminatory processor sharing
Operations Research, 2011Co-Authors: I M Verloop, Urtzi Ayesta, R NuoezqueijaAbstract:We analyze a generalization of the discriminatory processor-sharing (DPS) queue in a heavy-traffic setting. Customers present in the system are served simultaneously at rates controlled by a vector of weights. We assume that customers have phase-type Distributed Service requirements and allow that customers have different weights in various phases of their Service. In our main result we establish a state-space collapse for the queue-length vector in heavy traffic. The result shows that in the limit, the queue-length vector is the product of an exponentially Distributed random variable and a deterministic vector. This generalizes a previous result by Rege and Sengupta [Rege, K. M., B. Sengupta. 1996. Queue length distribution for the discriminatory processor-sharing queue. Oper. Res.44(4) 653--657], who considered a DPS queue with exponentially Distributed Service requirements. Their analysis was based on obtaining all moments of the queue-length distributions by solving systems of linear equations. We undertake a more direct approach by showing that the probability-generating function satisfies a partial differential equation that allows a closed-form solution after passing to the heavy-traffic limit. Making use of the state-space collapse result, we derive interesting properties in heavy traffic: (i) For the DPS queue, we obtain that, conditioned on the number of customers in the system, the residual Service requirements are asymptotically independent and Distributed according to the forward recurrence times. (ii) We then investigate how the choice for the weights influences the asymptotic performance of the system. In particular, for the DPS queue we show that the scaled holding cost reduces as classes with a higher value for dk/E(Bkfwd) obtain a larger share of the capacity, where dk is the cost associated to class k, and E(Bkfwd) is the forward recurrence time of the class-k Service requirement. The applicability of this result for a moderately loaded system is investigated by numerical experiments.
Kiran M Rege - One of the best experts on this subject based on the ideXlab platform.
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queue length distribution for the discriminatory processor sharing queue
Operations Research, 1996Co-Authors: Kiran M Rege, Bhaskar SenguptaAbstract:In this paper, we study a multiple class discriminatory processor-sharing queue. The queue is assumed to have Poisson input and exponentially Distributed Service times. In this discipline there are K classes of customers. When there are ni customers present in the system of class ii = 1, ', K, each member of class j receives a fraction of the server's capacity given by αj/âi=1Kniαi. Thus, associated with class i customers is a weight αi which determines the level of Service discrimination. For this problem, we find the moments of the queue-length distribution as a solution of linear simultaneous equations. We also prove a heavy traffic limit theorem for the joint queue-length distribution for this queue.
Marian Codreanu - One of the best experts on this subject based on the ideXlab platform.
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moment generating function of the aoi in multi source systems with computation intensive status updates
arXiv: Information Theory, 2021Co-Authors: Mohammad Moltafet, Markus Leinonen, Marian CodreanuAbstract:We consider a multi-source status update system in which status updates are transmitted as packets containing the measured value of the monitored process and a time stamp representing the time when the sample was generated. The packets of each source are generated according to the Poisson process and the packets are served according to an exponentially Distributed Service time. We assume that the received status update packets needs further processing before being used (hence, computation-intensive). This is mathematically modeled by introducing an additional server at the sink node. The sink server serves the packets according to an exponentially Distributed Service time. We introduce two packet management policies, namely, i) a preemptive policy and ii) a blocking policy and derive the moment generating function (MGF) of the AoI of each source under both policies. In the preemptive policy, a new arriving packet preempts any possible packet that is currently under Service regardless of the packet's source index. In the blocking policy, when a server is busy at the arrival instant of a packet the arriving packet is blocked and cleared. We assume that the same preemptive/blocking policy is employed in both transmitter and sink servers. Numerical results are provided to assess the results.
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average age of information for a multi source m m 1 queueing model with packet management
International Symposium on Information Theory, 2020Co-Authors: Mohammad Moltafet, Markus Leinonen, Marian CodreanuAbstract:We consider a status update system consisting of two independent sources, one server, and one sink. The packets of different sources are generated according to the Poisson process and the packets are served according to an exponentially Distributed Service time. We consider the following packet management policy. When the system is empty, any arriving packet immediately enters the server; when the server is busy, a packet of a source waiting in the queue is replaced if a new packet of the same source arrives. We derive the average age of information (AoI) of the considered M/M/1 queueing model by using the stochastic hybrid systems (SHS) technique. Numerical results are provided to show the effectiveness of the proposed policy.
Jesus L. Muros-cobos - One of the best experts on this subject based on the ideXlab platform.
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Distributed Service-Based Approach for Sensor Data Fusion in IoT Environments
Sensors, 2014Co-Authors: Sandra Rodríguez-valenzuela, Juan A. Holgado-terriza, Jose Miguel Gutierrez-guerrero, Jesus L. Muros-cobosAbstract:The Internet of Things (IoT) enables the communication among smart objects promoting the pervasive presence around us of a variety of things or objects that are able to interact and cooperate jointly to reach common goals. IoT objects can obtain data from their context, such as the home, office, industry or body. These data can be combined to obtain new and more complex information applying data fusion processes. However, to apply data fusion algorithms in IoT environments, the full system must deal with Distributed nodes, decentralized communication and support scalability and nodes dynamicity, among others restrictions. In this paper, a novel method to manage data acquisition and fusion based on a Distributed Service composition model is presented, improving the data treatment in IoT pervasive environments.
