System Performance: Measures and Environmental Effects

In this paper we analyze a tollbooth tandem queueing problem with an infinite number of servers. A customer starts service immediately upon arrival but cannot leave the system before all customers who arrived before him/her have left, i.e. customers depart the system in the same order as they arrive. Distributions of the total number of customers in the system, the number of departure-delayed customers in the system, and the number of customers in service at time t are obtained in closed form. Distributions of the sojourn times and departure delays of customers are also obtained explicitly. Both transient and steady state solutions are derived first for Poisson arrivals, and then extended to cases with batch Poisson and nonstationary Poisson arrival processes. Finally, we report several stochastic ordering results on how system performance measures are affected by arrival and service processes.

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Application of Statistical Quality Control in Testing Labs for Estimation of Machine Interference

Strategic Applications of Measurement Technologies and Instrumentation - Advances in Chemical and Materials Engineering ◽

10.4018/978-1-5225-5406-6.ch005 ◽

2019 ◽

pp. 77-98

Author(s):

Nitin K. Mandavgade ◽

Santosh B. Jaju ◽

Ramesh R. Lakhe

Keyword(s):

Performance Measures ◽

System Performance ◽

Testing Equipment ◽

Statistical Quality Control ◽

Test Results ◽

Uncertainty Of Measurement ◽

Testing Laboratories ◽

Machine Interference ◽

Analysis Of Results

The performance and maintenance of testing laboratories is a prime issue. The quality of coal test results not only depends on performance of individual results but it also depends on the performance of various tests in the same laboratory. Machine interference is a significant problem in many manufacturing system and testing equipment. The variation of results for testing equipment may be due to various factors which need to calculate the uncertainty of measurement to show the accuracy of the machine. In case of coal testing laboratory, the plant layout and surrounding environment affects the performance of the system. The machine interference comes under variable causes which may affect the result. This chapter proposes a methodology for constructing system performance measures, finding out the various factors responsible for variations in result. The chapter deals with estimation of machine interference existence using variable control chart approach for coal testing equipment. The analysis of results for such machine interference will be useful and significant for system designers and practitioners.

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Performance Measures for Multimodal Transportation Systems

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198196151800115 ◽

1996 ◽

Vol 1518 (1) ◽

pp. 85-93 ◽

Cited By ~ 6

Author(s):

Richard H. Pratt ◽

Timothy J. Lomax

Keyword(s):

Land Use ◽

Performance Measurement ◽

Travel Time ◽

Performance Measures ◽

System Performance ◽

Transportation Systems ◽

Regional Networks ◽

Multimodal Transportation ◽

Decision Context ◽

Multimodal Systems

Transportation systems analyses have been evolving as the decision context for improvement projects and programs has changed. The increased emphasis on the movement of persons and goods, and a recognition of the importance of system performance measures that address the needs and interests of the audiences for mobility information, will result in a very different set of procedures for evaluating transportation and land use infrastructure and policies. Some of the key underlying concerns of performance measurement for multimodal systems are presented. Definitions are included for congestion, mobility, and accessibility that are used to guide the development of performance measures. Travel time–based measures are seen as the most readily understandable quantities, and examples are used to show how mobility can be measured for locations, corridors, transit analyses, and regional networks.

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Two parallel finite queues with simultaneous services and Markovian arrivals

Journal of Applied Mathematics and Stochastic Analysis ◽

10.1155/s1048953397000439 ◽

1997 ◽

Vol 10 (4) ◽

pp. 383-405 ◽

Cited By ~ 2

Author(s):

S. R. Chakravarthy ◽

S. Thiagarajan

Keyword(s):

Markov Process ◽

Performance Measures ◽

System Performance ◽

Arrival Process ◽

Single Server ◽

Queueing Model ◽

Finite Capacity ◽

Numerical Examples ◽

Finite Queues ◽

Large State Space

In this paper, we consider a finite capacity single server queueing model with two buffers, A and B, of sizes K and N respectively. Messages arrive one at a time according to a Markovian arrival process. Messages that arrive at buffer A are of a different type from the messages that arrive at buffer B. Messages are processed according to the following rules: 1. When buffer A(B) has a message and buffer B(A) is empty, then one message from A(B) is processed by the server. 2. When both buffers, A and B, have messages, then two messages, one from A and one from B, are processed simultaneously by the server. The service times are assumed to be exponentially distributed with parameters that may depend on the type of service. This queueing model is studied as a Markov process with a large state space and efficient algorithmic procedures for computing various system performance measures are given. Some numerical examples are discussed.

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Effect of routing flexibility and sequencing rules on performance of stochastic flexible job shop manufacturing system with setup times: Simulation approach

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405415576060 ◽

2016 ◽

Vol 231 (2) ◽

pp. 329-345 ◽

Cited By ~ 7

Author(s):

Pankaj Sharma ◽

Ajai Jain

Keyword(s):

Performance Measures ◽

System Performance ◽

Manufacturing System ◽

Job Shop ◽

Flow Time ◽

Setup Times ◽

Flexible Job Shop ◽

Routing Flexibility ◽

Due Date ◽

Sequencing Rule

Routing flexibility is a major contributor towards flexibility of a flexible job shop manufacturing system. This article focuses on a simulation-based experimental study on the effect of routing flexibility and sequencing rules on the performance of a stochastic flexible job shop manufacturing system with sequence-dependent setup times while considering dynamic arrival of job types. Six route flexibility levels and six sequencing rules are considered for detailed study. The performance of manufacturing system is evaluated in terms of flow time related and due date–related measures. Results reveal that routing flexibility and sequencing rules have significant impact on system performance, and the performance of a system can be increased by incorporating routing flexibility. Furthermore, the system performance starts deteriorating as the level of route flexibility is increased beyond a particular limit for a specified sequencing rule. The statistical analysis of the results indicates that when flexibility exists, earliest due date rule emerges as a best sequencing rule for maximum flow time, mean tardiness and maximum tardiness performance measures. Furthermore, smallest setup time rule is better than other sequencing rules for mean flow time and number of tardy jobs performance measures. Route flexibility level two provides best performance for all considered measures.

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The Geo/Geo/1+1 Queueing System with Negative Customers

Mathematical Problems in Engineering ◽

10.1155/2013/182497 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Zhanyou Ma ◽

Yalin Guo ◽

Pengcheng Wang ◽

Yumei Hou

Keyword(s):

Performance Measures ◽

Waiting Time ◽

System Performance ◽

Queue Length ◽

Solution Method ◽

Queueing System ◽

Negative Customers ◽

Idle Period ◽

Matrix Geometric Solution ◽

Qbd Process

We study a Geo/Geo/1+1 queueing system with geometrical arrivals of both positive and negative customers in which killing strategies considered are removal of customers at the head (RCH) and removal of customers at the end (RCE). Using quasi-birth-death (QBD) process and matrix-geometric solution method, we obtain the stationary distribution of the queue length, the average waiting time of a new arrival customer, and the probabilities of servers in busy or idle period, respectively. Finally, we analyze the effect of some related parameters on the system performance measures.

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Engaging citizens in the co-production of a health system performance assessment framework: a case study in Ireland

10.21203/rs.3.rs-605225/v1 ◽

2021 ◽

Author(s):

Óscar Brito Fernandes ◽

Erica Barbazza ◽

Damir Ivanković ◽

Tessa Jansen ◽

Niek Klazinga ◽

...

Keyword(s):

Health System ◽

Performance Assessment ◽

Performance Measures ◽

System Performance ◽

Professional Associations ◽

Third Party ◽

Added Value ◽

Future Research ◽

Health System Performance ◽

Health System Performance Assessment

Abstract Background The launch in 2017 of the Irish 10-year reform programme Sláintecare represents a key commitment in the future of the health system. An important component of the programme was the development of a health system performance assessment (HSPA) framework. In 2019, the Department of Health of Ireland (DoH) and Health Service Executive (HSE) commissioned the technical support of researchers to develop an outcome-oriented HSPA framework, which should reflect the shared priorities of multiple stakeholders, including citizens. This study describes the method applied in the Irish context and reflects on the added value of using a citizen panel in the co-production of an HSPA framework. Methods A panel of 15 citizens was convened, recruited by a third-party company using a sampling strategy to achieve a balanced mix representing the Irish society. Panelists received lay-language preparatory materials prior to the meeting. Panelists used a three-color scheme to signal the inclusion and importance of performance measures. An exit questionnaire was administered to understand how participants experienced being part of the panel. The citizen panel was the first in a series of three panels towards the development of the HSPA framework, followed by panels including representatives of the DoH and HSE, and representatives from professional associations and special interest groups. Results The citizen panel generated 249 health performance measures ranging across 13 domains. Domains assessed as the most important included people-centeredness, coordination of care, and coverage. Prioritization of domains differed between panels. Citizen panelists shared a similar understanding of what a citizen panel involves and described their experience at the panel as enjoyable, interesting, and informative. Conclusions The engagement of citizens early on in the co-production process of the HSPA framework shaped the processes that followed, with the restating of priorities of the citizen panel informing decision-making throughout. Citizen engagement in HSPA development is essential for realizing value-based people-centered health systems and assuring an inclusive process that helps to generate trust and ownership of performance intelligence. Future research could expand on how citizen panels could be further engaged in co-creating mechanisms to assess, monitor, and report on the performance of health care systems.

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Perishable Inventory System with Bi-Level Service System

Stochastic Processes and Models in Operations Research - Advances in Logistics, Operations, and Management Science ◽

10.4018/978-1-5225-0044-5.ch012 ◽

2016 ◽

pp. 200-217

Author(s):

D. Gomathi

Keyword(s):

Steady State ◽

Performance Measures ◽

Service Time ◽

System Performance ◽

Service System ◽

Joint Probability ◽

Inventory System ◽

Service Time Distribution ◽

Perishable Inventory ◽

Perishable Inventory System

In this chapter we consider a perishable inventory system under continuous review at a bi-level service system with finite waiting hall of size N. The maximum storage capacity of the inventory is S units. We assumed that a demand for the commodity is of unit size. The arrival time points of customers form a Poisson process. The individual customer is issued a demanded item after a random service time, which is distributed as negative exponential. The effect of the two modes of operations on the system performance measures is also discussed. It is also assumed that lead time for the reorders is distributed as exponential and is independent of the service time distribution. The items are perishable in nature and the life time of each item is assumed to be exponentially distributed. The demands that occur during stock out periods are lost. The joint probability distribution of the number of customers is obtained in the steady-state case. Various system performance measures in the steady state are derived. The results are illustrated numerically.

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