Performance Of Queueing Systems Research Articles

Queuing analysis for improving performance in bacterial vaccine quality control process

The aim of the research is to analyze and improve the performance of the vaccine quality control queuing system to reduce delays and achieve the firm’s long-term goal on vaccine production capacity. The research focuses on the Bacterial Vaccine Quality Control (BVQC) at the largest vaccine manufacturers in Indonesia and Southeast Asia. The vaccines handled by BVQC include TT, DTP, BCG, BioTT, BioTd, DT, Td, and DTP-Hb-Hib. The BVQC operates a queuing system with eight servers, each assigned a fixed task. The existing system experienced delays ranging from 13 % to 61 % from January to June 2022. After identifying the queuing characteristics of the existing system, improvement proposals were suggested by modifying the assignment of the servers. This proposal was then simulated in November 2022, resulting in improved performance with no delays, a reduction in the length of the queue in the system (Lq) from 2.88 to 2.59, and a reduction in the average time spent in the system (Ws) from 0.0099 to 0.0044. The research suggests that modifying server assignments can be an effective method for improving the performance of a queuing system in vaccine quality control. This can lead to reduced delays, optimized queue lengths, and improved overall efficiency, potentially enhancing the firm’s ability to meet vaccine demand in the future.

Optimization of Teller Services Using Queuing Theory at XYZ Bank

Bank XYZ is one of the largest state-owned banks in Indonesia that provides various financial services. Currently Bank XYZ has 3 teller services only. This study aims to determine the use of customer queuing schemes currently used in XYZ bank teller services. The data processed is the arrival of customers who transact at the teller area of Bank XYZ. This study uses the Queuing Theory method with the M / M / S (Multiple Channel Single Phase) model and also uses FlexSim software. Then analyze with the addition of the number of tellers (services). Finally, a comparison is made between manual and software calculation methods. Based on the results of the data analysis, the optimal improvement in the application of the queuing system is to add 1 teller service to 4 teller services. The improvement in the performance of the queuing system is characterized by a reduction in the number of customers in line at peak hours 10.00 - 11.00 which initially amounted to 11 people reduced to 3 people and the average waiting time of customers in the queue from 10.08 minutes to 4.02 minutes. Therefore, optimal queuing system performance can be ensured by increasing the number of tellers to four.

Analysis of a Pre-Emptive Two-Priority Queuing System with Impatient Customers and Heterogeneous Servers

This paper presents a queuing system model that incorporates multiple priorities, multiple abandonments, and heterogeneous servers. Waiting for service easily leads to impatient behaviors. The impact of two kinds of impatient behaviors, balking and reneging, on queueing system performance is examined. The problem is formulated as continuous-time Markov chains. It also introduces a special state called the non-sojourn state to record the number of customers who abandon the system. The state transition rate matrix is transformed into a block tridiagonal matrix by appropriately setting the state numbers. A novel indicator called interstate transition frequency is proposed, which aids in distinguishing state transitions during the system evaluation process. Based on the interstate transition frequency, a set of indicators is derived to offer additional analytical perspectives for the queuing system. Finally, the proposed model is applied to an automobile repair shop to validate its effectiveness in practical scenarios.

Analysis of efficiency between self-check in and conventional check in with queue method (case study at terminal 3 Soekarno-Hatta airport)

Queues occur as a consequence of the limited-service facilities. Queuing systems can occur in various places and times, one of which is checking in aircraft at Soekarno-Hatta International Airport Cengkareng. Comparative analysis of the time efficiency of the queuing system needs to be done to help make decisions on the implementation of the check in system to improve service performance in order to achieve customer satisfaction. This study aims to analyze the comparison of queue time efficiency between self-check in and conventional check using the queuing method. The population in this study are prospective passengers who will check-in at Terminal 3 Soekarno - Hatta Airport, the sample used is passengers who come and queue at the ticket check-in counter of Soekarno - Hatta Airport Tangerang to take boarding passes from February 2022. Sampling method using purposive sampling. The data collection method used primary data and secondary data. The data analysis method uses the Queuing System Performance analysis with the Multiple Line Queuing Model (M/M/S). The results of the research are expected to help solve problems, assist decision making and determine policies related to long queues at check-in activities at airports.

Application of queuing theory and simulation to reduce waiting time in dental hospitals

Background: Patient waiting time is an important factor in the management of the health sector. This study aimed to develop a suitable queuing theory and simulation technique to optimize dental hospital management.Methods: A descriptive-analytical study was performed in a dental hospital in Tehran, Iran. A sample of 3364 patients referred to the hospital was selected to calculate the patient flow and queuing system performance. After an initial data assessment, the dental hospital queuing system performance indicators were calculated for two shifts. The queuing system of the current situationwas modeled using ARENA software, and two scenarios were examined.Results: The average number of patients waiting in the queuing system was 38 and 17 in the morning and evening, respectively. The average time patients spend waiting in the system was 110 and 49 minutes in the morning and evening, respectively. The two scenarios, based on the simulated queuing network model, showed that in the first scenario, by using two nurses (one male and one female) as triage clerks for filing requests, one clerk for managing financial records, and one information desk secretary, the average queue length and waiting time were reduced to 0.02 patients and 4 minutes, respectively. In the second scenario, by using two nurses (one male and one female) as triage clerks for filing requests and two secretaries (one male and one female) for financial record management and registration, the average queue length and the waiting time in triage were reduced to 0.03 people and 5 minutes, respectively.Conclusion: Based on the results, using queuing theory and simulation techniques can improve the queuing status of health centers without any changes in the number of staff and only by implementing a suitable rearrangement in staff duties, establishing parallel service lines in busy service-providing centers, and using nurses able to multitask.

THE STATES’ FINAL PROBABILITIES ANALYTICAL DESCRIPTION IN AN INCOMPLETELY ACCESSIBLE QUEUING SYSTEM WITH REFUSALS

Context. There is a problem of forecasting the efficiency of real queuing systems with refusals in the case of incomplete accessibility of service devices for the input flow of requirements. The solution of problem is necessary to create the possibility of more accurate design and control of such systems operation in real time. Objective. The aim of the research is to obtain an analytical description of the state’s final probabilities in a Markov queuing system with refusals and with incomplete accessibility of service devices for the input flow of requirements that is necessary to forecast the values of the queuing system performance indicators. Method. The probabilities of queuing systems’ states with refusals in the case of incomplete accessibility of service devices for the input flow of requirements are described by Kolmogorov differential equations. In a stationary state, these equations are transformed into a linearly dependent homogeneous system of algebraic equations. The number of equations is determined by the setdegree and for modern queuing and communication systems can be in the thousands, millions and more. Therefore, an attempt to predict the efficiency of a system is faced with the need to write down and numerically solve a countable set of algebraic equations systems that is quite difficult. The key idea of the proposed method for finding an analytical description of final probabilities for a given queuing system was the desire to move from the description of individual states (of 2n amount) to the description of groups of system states (of n+1 number) and to localize the influence of incomplete accessibility of service devices for the input flow of requirements in multiplicative functions of incomplete accessibility. Such functions allow obtaining the required analytical description and assessing the degree of the final probabilities transformation, in comparison with known systems, as well as assessing the forecasted values of the noted queuing system’s efficiency indicators when building a system and choosing the parameters for its controlling. Results. For the first time analytical expressions are obtained for the final probabilities of the queuing system states with refusals and with incomplete accessibility of service devices for the input flow of requirements, which makes it possible to evaluate as well as forecast values of all known system efficiency indicators. Conclusions. The resulting description turned out to be a general case for well-known type of Markov queuing systems with refusals. The results of the numerical experiment testify in favor of correctness the obtained analytical expressions for the final probabilities and in favor of possibility for their practical application in real queuing systems when solving problems of forecasting efficiency, as well as analyzing and synthesizing the parameters of real queuing systems.

THE STATES FINAL PROBABILITIES ANALYTICAL DESCRIPTION IN QUEUING SYSTEM WITH AN ENTRANCE FLOW OF REQUIREMENTS GROUPS, WITH WAITING AND LEAVING THE QUEUE

Context. The problem of predicting the efficiency of real queuing systems in the event of a possible arrival of requirements groups and leaving of “impatient” requirements from the queue. The aim of the study was to model the operation of such systems to create opportunities to control their operation in real time. Objective. The aim of the research is to obtain an analytical description of the state’s final probabilities in a Markov queuing system with an input flow of requirements groups, with individual service of requirements, with a limited number of waiting places and with individual leaving of “impatient” requirements from the queue that is necessary to predict the values of the queuing system performance indicators.Method. The probabilities of queuing systems states with an input flow of requirements groups with a random composition and with leaving of “impatient” requirements from the queue are described by the Kolmogorov differential equations. In a stationary state, these equations are transformed into a linearly dependent homogeneous system of algebraic equations. The structure of the equations depends on the numerical values of the input flow requirements group’s parameters and the controlled service system. Therefore, an attempt to predict the efficiency of a system is faced with the need to write down and numerically solve a countable set of algebraic equations systems that is quite difficult. The key idea of the proposed method for finding an analytical description of the final probabilities for the specified queuing system was the desire to localize the influence of requirements groups in the input flow on the operation of the queuing system in multiplicative non-ordinary functions. Such functions allow obtaining the required analytical description and assessing the degree of the final probabilities transformation, in comparison with known systems, as well as assessing the predicted values of the noted queuing system efficiency indicators when choosing the parameters for controlling its operation. Results. For the first time analytical expressions are obtained for the final probabilities of the queuing system states with an input flow of random composition requirements groups, with a limited number of waiting places, with individual service and leaving “impatient” requirements from the queue, which makes it possible to evaluate all known indicators of the system’s performance. Conclusions. The resulting description turned out to be a general case for well-known types of Markov queuing systems with non-ordinary and with the simplest input flow of requirements. The results of the numerical experiment testify in favor of the correctness of the obtained analytical expressions for the final probabilities and in favor of the possibility of their practical application in real queuing systems when solving problems of forecasting efficiency, as well as analyzing and synthesizing the parameters of real queuing systems.

Service delays in strongly linked network communities

We analyze aggregated traffic dynamics obtained from strongly linked network communities. Our results based on two empirical data traces from university campus networks indicate that neglecting the statistical links between traffic patterns generated by individual network nodes leads to the drastic underestimation of both waiting and sojourn times. We also show that similar effects can be observed in simulated traffic patterns obtained by agent based modeling. Moreover, we suggest several indices that could be used to quantify the links between nodes and show their relation with the queuing system performance indicators.

Application of Discrete Event Simulation (DES) for Queuing System Improvement at Hypermarket

This paper focuses on the development of a computer simulation model for improving the queuing system at a hypermarket using Discrete Event Simulation (DES) and to propose the most efficient hypermarket queuing system for overall improvement. Data were collected from the Hypermarket A using the time study. The method of this study is using modeling and simulation. Arena Simulation Software is used to develop the model to replicate the actual system. Three scenarios had been tested, and the alternatives will be ranked based on the level of the efficiency of the system performance. The most efficient queuing system is identified based on the scenario analysis. In this study, the waiting time for each customer can be improved by up to 26%, which equivalent to 5.24 minutes. Overall, this study contributes to a better understanding of the queuing system performance.

Estudo de filas e análise qualitativa do desempenho de um restaurante universitário

Verificar o desempenho de operações em serviço pode auxiliar na indicação de oportunidades de melhoria dessas operações. Neste contexto, o presente artigo tem o objetivo de verificar em uma escala de 0% a 100% o nível de serviço de uma operação de produção (restaurante universitário) segundo cinco objetivos de desempenho: qualidade do serviço, qualidade do produto, flexibilidade do produto, custo do produto e desempenho do sistema de filas. Para alcançar o objetivo proposto, estruturou-se um procedimento composto por quatro etapas. Essas etapas envolvem (1) a definição do local de aplicação e suas características, (2) a coleta de dados quantitativos em campo e definição das características operacionais da fila, (3) a definição e a coleta de dados qualitativos em campo e tabulação desses dados, além da (4) análise dos dados qualitativos e características operacionais da fila. De um modo geral, a qualidade do serviço, a qualidade do produto e a flexibilidade do produto se destacaram com baixo nível de insatisfação. No caso do desempenho do sistema de filas, há oportunidade de melhoria, pois o tempo real médio de espera é superior ao tempo que os respondentes acham adequado para esperar na fila. Outro ponto de melhoria é o custo do produto, com redução ideal deste valor em 33%, segundo os respondentes.

Performance Analysis of Cloud Computing Center with Queueing Model

Cloud computing is a novel raising computing resource allocation. Successful development of cloud computing paradigm necessitates explicit performance evaluation of cloud data centers. The computing resource allocation and performance managing have been one of the most important septets of cloud computing. In this paper, we consider the cloud center as a queuing system with single task arrivals and a task request buffer of infinite capacity. We assess the performance of queuing system by using an analytical model and solve it to obtain important performance factors like mean number of tasks in the system. Using this model in order to evaluate the performance analysis of cloud server farms and obtained solved it to obtain accurate estimation of complete probability distribution of the request response time and other paramount performance indicators.

THE GENERALIZED MODEL OF SITUATIONAL PRIORITIES IN ACCESS SYSTEMS

Objective. Under conditions of limited resources queuing system (QS) with disciplines of different priorities are a powerful conflict-resolving tool. The aim of the paper is to generalize the model of situational priority service based on QS with two streams for one or two servicing devices, and to offer possible scenarios for implementation of situational priorities in access systems. Methods. The generalized analytical model of queuing system was realized according to the Markov chains theory. This model substantiates the best scenarios that justify the situational priorities implementation. Results. The result is an analytical description of the generalized model of QS with two streams for one or two servicing devices and the quantitative analysis of scenarios implementation of service priority in access systems. The performance analysis for each stream and overall QS performance was conducted. The recommendations for effective usage of priority service disciplines based on the proposed scenarios were given. Conclusions. One of the possible scenarios of situational priorities algorithm implementation was proposed based on the mathematical resource access model. The points of priority change by the selected value of system productivity were illustrated based on the quantitative data.

Universal model for collective access patterns in the Internet traffic dynamics: A superstatistical approach

We suggest a universal phenomenological description for the collective access patterns in the Internet traffic dynamics both at local and wide area network levels that takes into account erratic fluctuations imposed by cooperative user behaviour. Our description is based on the superstatistical approach and leads to the q-exponential inter-session time and session size distributions that are also in perfect agreement with empirical observations. The validity of the proposed description is confirmed explicitly by the analysis of complete 10-day traffic traces from the WIDE backbone link and from the local campus area network downlink from the Internet Service Provider. Remarkably, the same functional forms have been observed in the historic access patterns from single WWW servers. The suggested approach effectively accounts for the complex interplay of both “calm” and “bursty” user access patterns within a single-model setting. It also provides average sojourn time estimates with reasonable accuracy, as indicated by the queuing system performance simulation, this way largely overcoming the failure of Poisson modelling of the Internet traffic dynamics.

Bounding tandem queuing system performance with variational theory

Queuing models are often used for traffic analysis, but analytical results concerning a system of queues are rare, thanks to the interdependence between queues. In this paper, we present an analysis of queuing systems to obtain bounds of their performance without studying the details of individual queues. Queuing dynamics is formulated in continuous-time, subject to variations of demands and bottleneck capacities. Our analysis develops new techniques built on the closed-form solution to a generalized queuing model for a single bottleneck. Taking advantage of its variational structure, we derive the upper and lower bounds for the total queue length in a tandem bottleneck system and discuss its implication for the kinematic wave counterpart. Numerical experiments are conducted to demonstrate the appropriateness of the derived upper and lower bounds as approximations in a stochastic setting.

Bounding Queuing System Performance with Variational Theory

Queuing models are often used for traffic analysis, but analytical results concerning a system of queues are rare, thanks to the interdependence between queues. In this paper, we present an analysis of queuing systems to obtain bounds of their performance without studying the details of individual queues. Queuing dynamics is formulated in continuous-time, subject to variations of demands and bottleneck capacities. Our analysis develops new techniques built on the closed-form solution to a generalized queuing model for a single bottleneck. Taking advantage of its variational structure, we derive the upper and lower bounds for the total queue length in a tandem bottleneck system and discuss its implication for the kinematic wave counterpart. Numerical experiments are conducted to demonstrate the appropriateness of the derived upper and lower bounds as approximations in a stochastic setting.

Structural Equation Modeling Analysis of Queuing System Performance at Thailand’s Provincial Electricity Authority (PEA)

Structural Equation Modeling Analysis of Queuing System Performance at Thailand’s Provincial Electricity Authority (PEA)

Pareto Improving Coordination Policies in Queueing Systems: Application to Flow Control in Emergency Medical Services

Coordination policies that balance server loads are well known for improving queueing-system performance. However, in queueing systems with independent service agents that may decline to participate in the coordination mechanism, a sustainable policy must not only benefit the system, but also each individual agent. As a motivating example, we use the emergency-medicine setting: Emergency departments act as independent agents and overcrowding has a direct impact on the service quality. In such settings, agents are interested in performance measures that address the expected number of patients and the risk of being overcrowded; at the same time, the agents do not want to see a reduction in the expected revenue or market share as a result of coordination. We propose coordination policies that provide improvement on multiple performance measures for all agents and guarantee that the expected arrival rate and hence, the expected revenue, is preserved for each agent in the system.

ANALISIS SISTEM ANTRIAN PADA LOKET PEMBAYARAN PT. PLN (PERSERO) AREA BALI SELATAN RAYON KUTA

The purpose of the analysis of queuing systems is to find out the model and the performance of queuing system was run. The research was conducted at PT. PLN (Persero) South Bali Area Rayon Kuta and the issue raised is about the analysis of queuing systems at the payment counter. Model queue is determined based on the Kendall notation and performance of queuing systems can be determined by calculating the utilization factor. At payment counter, the queuing model used is a model (M/G/4):(GD/?/?). The performance of queuing system at payment counter of PT. PLN (Persero) South Bali Area Rayon Kuta is less effective because each servers was busy on average only between 30% – 50% of working hours so that more time unemployed servers.

Game theoretic aspects of crowd renting

Politicians and businessmen use various strategies to outwit their opponents. One such strategy is crowd renting, a powerful virtual strategy. A mathematical model developed by Nwobi-Okoye using game theory is used to show that crowd renting would always be the equilibrium strategy in strategic interactions involving political actors and businesses, provided the cost of using such strategies does not exceed a certain critical threshold where using it would no longer be the equilibrium strategy. It is equally shown that crowd renting would improve the electoral/business fortunes of parties/candidates/businesses and queuing system performance by increasing the number of possible voters or customers as the case may be. Finally it is shown mathematically that delaying voting in opposition strongholds or delaying the start of business by an opponent makes the opposition or opponent less likely to win. Keywords: Crowd renting; Game theory; Equilibrium; Virtual strategy

PERFORMANCE ANALYSIS FOR QOS PROVISIONING IN MPLS/DIFFSERV- BASED IP NETWORKS WITH NON-PREEMPTIVE PRIORITY QUEUING SYSTEM

A typical operating environment of a packet switching (store-and-forward) computer communication network is that it is shared by many users with different classes of packets. Packets may be classified in a very general fashion by types of users, messages, applications, transactions, response time requirements, packet parameters such as packet rate and length, and by network parameters such as source-destination and path length. A well-designed network must provide access and performance assurance to all packet classes. An architecture for designing such a communication network is presented in [1]. This architecture is based on MPLS as an underlying technology used for IP transport and DiffServ-like mechanisms for QoS provision which use simple priority queuing to differentiate several traffic classes by assigning them different delay targets. In this paper, we introduce a mathematical model for performance evaluation for QoS Provisioning in MPLS/DiffServ-Based IP Networks. This mathematical model is formulated to evaluate the performance of the proposed architecture described in [1]. Two parts are considered in the evaluation. One, is the analysis of the proposed QoS routing algorithms that are used in the proposed architecture, the other is the analysis of the average packet delay over the network. An M/G/1 Non-preemptive priority queuing system is used as the evaluation model to analyze the average packet delay over the network. Relative MPLS/DiffServ with Non-Preemptive Priority Queuing system performance compared to MPLS/DiffServ without priority (FIFO)[2] is evaluated. The results indicate that for well-designed MPLS/DiffServ equipments, original IP packet delay can be reduced by 39% or more with FIFO queuing system [2] and 42% or more with Nonpreemptive priority queuing system