Operations Research, Systems Engineering and Industrial Engineering Commons^™

A Recommendation System For Meta-Modeling: A Meta-Learning Based Approach, Can Cui, Mengqi Hu, Jeffery D. Weir, Teresa Wu

Faculty Publications

Various meta-modeling techniques have been developed to replace computationally expensive simulation models. The performance of these meta-modeling techniques on different models is varied which makes existing model selection/recommendation approaches (e.g., trial-and-error, ensemble) problematic. To address these research gaps, we propose a general meta-modeling recommendation system using meta-learning which can automate the meta-modeling recommendation process by intelligently adapting the learning bias to problem characterizations. The proposed intelligent recommendation system includes four modules: (1) problem module, (2) meta-feature module which includes a comprehensive set of meta-features to characterize the geometrical properties of problems, (3) meta-learner module which compares the performance of instance-based …

A Simulation Model For Decision Support In Business Continuity Planning, Marissa Anne Mosunich

Master's Theses

Enterprises with a global supply network are at risk of lost revenue as a result of disruptive disasters at supplier locations. Various strategies exist for addressing this risk, and a variety of types of research has been done regarding the identification, assessment and response to the risk of disruption in a supply chain network.

This thesis establishes a decision model to support Business Continuity Planning at the first-tier supplier level. The decision model incorporates discrete-event simulation of supply chain networks (through Simio software), Monte Carlo simulation, and risk index optimization. After modeling disruption vulnerability in a supply chain network, costs …

A Meta-Architecture Analysis For A Coevolved System-Of-Systems, George Anthony Muller Iv

Masters Theses

"Modern engineered systems are becoming increasingly complex. This is driven in part by an increase in the use of systems-of-systems and network-centric concepts to improve system performance. The growth of systems-of-systems allows stakeholders to achieve improved performance, but also presents new challenges due to increased complexity. These challenges include managing the integration of asynchronously developed systems and assessing SoS performance in uncertain environments.

Many modern systems-of-systems must adapt to operating environment changes to maintain or improve performance. Coevolution is the result of the system and the environment adapting to changes in each other to obtain a performance advantage. The complexity …

Optimal Energy Management System For A Net Zero Building Using Multi-Agent Systems Approach, Arzhang Ghassemi Pashakalaei

Open Access Theses & Dissertations

Buildings have a significant impact on energy usage and the environment. Much of the research in architectural sustainability has centered on economically advanced countries because they consume the most energy and have the most resources. However, sustainable architecture is important in developing countries, where the energy consumption of the building sector is increasing significantly. The aims of this Thesis are investigating using the hybrid system, which formed by interconnecting two source of renewable energy as solar (PV arrays) and wind (turbine) along with city grid for compensation purposes wherever it is required. In this Thesis, after literature review, we consider …

Electronic Warfare Receiver Resource Management And Optimization, William Metz

Walden Dissertations and Doctoral Studies

Optimization of electronic warfare (EW) receiver scan strategies is critical to improving the probability of surviving military missions in hostile environments. The problem is that the limited understanding of how dynamic variations in radar and EW receiver characteristics has influenced the response time to detect enemy threats. The dependent variable was the EW receiver response time and the 4 independent variables were EW receiver revisit interval, EW receiver dwell time, radar scan time, and radar illumination time. Previous researchers have not explained how dynamic variations of independent variables affected response time. The purpose of this experimental study was to develop …

Applications Of Simulation And Optimization Techniques In Optimizing Room And Pillar Mining Systems, Angelina Konadu Anani

Doctoral Dissertations

"The goal of this research was to apply simulation and optimization techniques in solving mine design and production sequencing problems in room and pillar mines (R&P). The specific objectives were to: (1) apply Discrete Event Simulation (DES) to determine the optimal width of coal R&P panels under specific mining conditions; (2) investigate if the shuttle car fleet size used to mine a particular panel width is optimal in different segments of the panel; (3) test the hypothesis that binary integer linear programming (BILP) can be used to account for mining risk in R&P long range mine production sequencing; and (4) …

Spare Parts On Demand Using Additive Manufacturing : A Simulation Model For Cost Evaluation., Stefan Jedeck

Electronic Theses and Dissertations

Little is known about the impact of additive manufacturing in the spare part supply chain. A few studies are available, but they focus on specific parts and their applications only. A general model, which can be adapted to different applications, is nonexistent. This dissertation proposes a decision making framework that enables an interested practitioner/manager to decide whether using additive manufacturing to make spare parts on demand is economical when compared to conventional warehousing strategy. The framework consists of two major components: a general discrete event simulation model and a process of designing a wide range of simulation scenarios. The goal …

Toward A Theory Of Multi-Method Modeling And Simulation Approach, Mariusz A. Balaban

Computational Modeling & Simulation Engineering Theses & Dissertations

The representation via simulation models can easily lead to simulation models too simple for their intended purpose, or with too much detail, making them hard to understand. This problem is related to limitations of the modeling and simulation methods. A multi-method Modeling and Simulation (M&S) approach has the potential for improved representation by taking advantage of methods' strengths and mitigating their weaknesses. Despite a high appeal for using multiple M&S methods, several related problems should be addressed first. The current level of theoretical, methodological, and pragmatic knowledge related to a multi-method M&S approach is limited. It is problematic that there …

Experimental And Numerical Study Of High-Speed Friction Stir Spot Welding Of Advanced High-Strength Steel, Utsab Karki

Theses and Dissertations

With the desire to lighten the frame while keeping or increasing the strength, Advanced High-Strength Steels (AHSS) have been developed for use in the automotive industry. AHSS meet many vehicle functional requirements because of their excellent strength and acceptable ductility. But joining AHSS is a challenge, because weldability is lower than that of mild steels. Friction stir spot welding (FSSW) is a solid state joining process that can provide a solution to the weldability issues in AHSS, but FSSW has not been studied in great detail for this application. In this work, Si3N4 tools were used for FSSW experiments on …

The Programmatic Generation Of Discrete-Event Simulation Models From Production Tracking Data, Christopher Rand Smith

Theses and Dissertations

Discrete-event simulation can be a useful tool in analyzing complex system dynamics in various industries. However, it is difficult for entry-level users of discrete-event simulation software to both collect the appropriate data to create a model and to actually generate the base-case simulation model. These difficulties decrease the usefulness of simulation software and limit its application in areas in which it could be potentially useful. This research proposes and evaluates a data collection and analysis methodology that would allow for the programmatic generation of simulation models using production tracking data. It uses data collected from a GPS device that follows …

Compressibility Measurement And Modeling To Optimize Flow Simulation Of Vacuum Infusion Processing For Composite Materials, Paul Hannibal

Theses and Dissertations

Out-of-autoclave manufacturing processes for composite materials are increasing in importance for aerospace and automotive industries. Vacuum Infusion processes are leading the push to move out of the autoclave. An understanding of the various process parameters associated with resin infusion is necessary to produce quality product. Variance in compaction, resin, and vacuum pressures are studied, concentrating on developing a compaction pressure profile as it relates to fiber volume fraction. The purpose of this research is twofold: (1) to show and quantify the existence of a resin pressure gradient in compression testing using rigid tooling, and (2) to use measured test data …

A Framework For Safety Training Using Virtual Reality Software, Rana Riad

Electronic Theses and Dissertations

Safety training is a vital component to the well-being of individuals in all industries. With technology advancing at the current pace, conventional training methods are no longer the most effective way to communicate information. There is a strong need for safety training that incorporates new methods and forms of communication to obtain higher levels of comprehension. Virtual reality systems offer a highly customizable and interactive form of delivering information to users. This research addresses major gaps in the field of safety training using virtual reality systems and provides a design framework for creating a virtual safety-training system. A model for …

Using The Delta-Model For End-Stage Liver Disease To Improve The Decision-Making Process For The Donor Liver System, Joanne Chin

Walden Dissertations and Doctoral Studies

The purpose of this experimental research was to determine whether using delta-MELD as a criterion for the liver transplant patient selection process could improve the U.S. liver allocation system. This research closed a gap in current literature on the utility of delta-MELD for liver transplant patient selection. The frameworks of systems theory, the analytic hierarchy process, and the Kalman filter contributed to the development of 2 simulation models of the liver allocation system: one that used delta-MELD and one that did not use delta-MELD. The research question examined whether using delta-MELD could improve the liver allocation system by reducing the …

Lateral Dynamics Of Multiple Trailer Trucks In Windy Environments, David Wafer

All Theses

The lateral response of three-trailer commercial vehicles has been assessed using the simulation package TruckSim^TM. Aerodynamic and mechanical characterizations for the vehicle were developed for this investigation. Simulations were carried out with various aerodynamic and load configurations with several different arbitrarily defined crosswinds. The aerodynamic configurations were tested in constant and random crosswinds. The load configurations were tested only in random crosswinds. Each aerodynamic configuration differed by the aerodynamic side-force coefficient for the trailers. Each load configuration consisted of reducing the payload in a single trailer. The tractor was identically defined for each load and aerodynamic configuration. Increasing …

Strategies To Improve The Efficiency Of Emergency Medical Service (Ems) Systems Under More Realistic Conditions, Kanchala Sudtachat

All Dissertations

Emergency medical service (EMS) systems provide medical care to pre-hospital patients who need rapid response and transportation. This dissertation proposes a new realistic approach for EMS systems in two major focuses: multiple unit dispatching and relocation strategies. This work makes recommendations for multiple-unit dispatch to multiple call priorities based on simulation optimization and heuristics. The objective is to maximize the expected survival rate. Simulation models are proposed to determine the optimization. A heuristic algorithm is developed for large-scale problems. Numerical results show that dispatching while considering call priorities, rather than always dispatching the closest medical units, could improve the effectiveness …

A Methodology For Designing Airports For Enhanced Security Using Simulation, Oliver Nwofia, Christopher A. Chung

Journal of Aviation Technology and Engineering

With the advent of the new security measures, today’s airports have become increasingly complex and congested. Air and passenger traffic continues to increase; consequently, the need for intelligent design concepts is required. Unlike all other existing airport designs that focused exclusively on operational performance, this study focused on the development of a new airport terminal design methodology that takes a proactive approach to minimizing the effects of security disruptions while simultaneously maximizing operational performance and passenger flow. The study addressed the impact of security operations on both the design of airport facilities and passenger flows, and discussed options and scenarios …

Using Discrete Event Simulation To Improve The Patient Care Process In The Emergency Department Of A Rural Kentucky Hospital., Molly Cassaro Jones

Electronic Theses and Dissertations

The patient care process of a rural Kentucky hospital is a complex process that must be flexible in order to deal with a large variety of patient needs and a fluctuating patient volume where all patients are unscheduled. A simulation model of an average month in the emergency department was built using the Arena Simulation package. Methods for creating a simulation using Arena are included in this work. Statistics were generated from a number of different sources to create an accurate representation of the model. The Hospital reporting shows a need to improve on two quality measures being tracked, the …

Developing A Holistic Modeling Approach For Search-Based System Architecting, Renzhong Wang, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper proposes a holistic modeling approach that combines the capabilities of Object Process Methodology (OPM), Colored Petri Net (CPN), and feature model. The resultant holistic model not only can capture the structural, behavioral, and dynamic aspects of a system, allowing simulation and strong analysis methods to be applied, it can also specify the architectural design space. This modeling approach is developed to facilitate the implementation of search-based system architecting where search algorithms are used to explore design trade space for good architecture alternatives. Such architecting approach integrates certain model construction, alternative generation, simulation, and assessment processes into a coherent …

A Methodology For Scheduling Operating Rooms Under Uncertainty, Marbelly Paola Davila

USF Tampa Graduate Theses and Dissertations

An operating room (OR) is considered to be one of the most costly functional areas within hospitals as well as its major profit center. It is known that managing an OR department is a challenging task, which requires the integration of many actors (e.g., patients, surgeons, nurses, technicians) who may have conflicting interests and priorities.

Considering these aspects, this dissertation focuses on developing a simulation based methodology for scheduling operating rooms under uncertainty, which reflects the complexity, uncertainty and variability associated with surgery.

We split the process of scheduling ORs under uncertainty into two main components. First, we designed a …

Evaluating The E-Consult Process For Diabetes Care Delivery At An Outpatient Care Clinic, Brian M. Zoll

Browse all Theses and Dissertations

The occurrence of one of the most common chronic conditions in the U.S., diabetes, is expected to rise 53% from 24 million cases in 2003 to 37 million cases in 2023. The U.S. Veterans Health Administration (VHA) is not immune to this. The VHA has experienced an $820 million increase spending on diabetes patients between 2000 and 2008. The VHA has tried to keep the growth of chronic care costs in check through improvements in patient access to care by expanding its network of community-based outpatient clinics. Other methods the VHA has used to curb chronic care spending costs are …

A Simulation-Based Decision Support System To Model Complex Demand Driven Heathcare Facilities, Amr Arisha, Michael Thorwarth

Conference papers

Simulating healthcare processes is a sophisticated endeavor. Treatment processes and patient arrival patterns differ significantly in their statistical attributes and implicate a high degree of variability. In addition, there are several types of interconnected processes of medical staff involved that accompany a patient’s journey through the healthcare facility. Replicating this behavior with process flow models in a discrete event simulation model is highly complex and therefore difficult to create while maintaining a high degree of precision. A framework is thus introduced which delivers an algorithm that allows to implement Multiple Participant Pathway Modeling (MPPM) under the consideration of Flexible Resource …

Capacity Planning For Elderly Care In Ireland Using Simulation Modeling, Mohamed Ragab, Waleed Abo Hamad, Amr Arisha

Conference papers

Global population aging is creating an immense pressure on healthcare facilities making them unable to cope with the growing demand for elderly healthcare services. Current demand-supply gaps result in prolonged waiting times for patients and substantial cost burdens for healthcare systems due to delayed discharges. This paper describes a project aimed at presenting modeling and simulation to address elderly care pathways within the Irish healthcare sector. The management of frail patients admitted to acute hospitals and the introduction of the new intermediate care beds are alternative interventions that healthcare executives are interested in simulating to examine their impact on the …

Districting And Dispatching Policies To Improve The Efficiency Of Emergency Medical Service (Ems) Systems, Damitha Bandara

All Dissertations

The major focus of Emergency Medical Service (EMS) systems is to save lives and to minimize the
effects of emergency health incidents. The efficiency of the EMS systems is a major public concern. Thus,
over the past three decades a significant amount of research studies have been conducted to improve the performance
of EMS systems. The purpose of this study is also to improve the performance of EMS system.
The contribution of this research towards improving the performance of EMS systems is twofold. One area
is to implement optimal or near optimal dispatching strategies for EMS systems and the other …

Improving Health Care Quality And Safety: The Development And Assessment Of Laparoscopic Surgery Instrumentation, Practices And Procedures, Bernadette Mccrory

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Adverse events due to medical errors are a leading cause of death in the United States exceeding the mortality rates of motor vehicle accidents, breast cancer and AIDS. Improvements can and should be made to reduce the rates of preventable surgical errors since they account for nearly half of all adverse events within hospitals. Although minimally invasive surgery has proven patient benefits such as reduced postoperative pain and hospital stay, its operative environment imposes substantial physical and cognitive strain on the surgeon increasing the risk of error. In order to mitigate errors and protect patients, a multidisciplinary approach was taken …

A Study Of Queuing Theory In Low To High Rework Environments With Process Availability, Adam J. Brown

Theses and Dissertations--Manufacturing Systems Engineering

In manufacturing systems subject to machine and operator resource constraints the effects of rework can be profound. High levels of rework burden the resources unnecessarily and as the utilization of these resources increases the expected queuing time of work in process increases exponentially. Queuing models can help managers to understand and control the effects of rework, but often this tool is overlooked in part because of concerns over accuracy in complex environments and/or the need for limiting assumptions. One aim of this work is to increase understanding of system variables on the accuracy of simple queuing models. A queuing model …

Computational System Architecture Development Using A Holistic Modeling Approach, Renzhong Wang, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper presents an innovative system architecture development framework that allows the search of optimum architecture solutions within large design space by automating certain model construction, alternative generation, simulation, and assessment tasks. Such framework is facilitated by a holistic modeling approach that combines the capabilities of Object Process Methodology (OPM), Colored Petri Net (CPN) and feature model. the resultant holistic model not only can capture the structural, behavior, and dynamic aspects of a system, allowing strong analysis methods to be applied, but also can specify the architectural design space allowing generation of architecture alternatives that cover it. the proposed framework …

Simulation-Based Optimisation Model For The Lean Assessment In Sme: A Case Study, Amr Arisha, Amr Mahfouz, John Shea

Conference papers

Due to their space limitation and small production scale, small and medium enterprises (SME) are vulner-able to rapid changes. Lean principles are considered as effective improvement approach to eliminate sys-tem’s waste and inefficiencies. Although much of the academic materials have addressed the lean practic-es into large, global companies, they can still be adjusted to SMEs. Risks are usually associated with lean implementation process due to the drastic required changes in business policies and operations. Simulation can be successfully used to predict the impact of the proposed changes ahead of the implementation which helps to mitigate risks. Integrating simulation with optimization …

Executable System Architecting Using Systems Modeling Language In Conjunction With Colored Petri Nets In A Model-Driven Systems Development Process, Renzhong Wang, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

This work proposes an executable system architecting paradigm for discrete-event system modeling and analysis through integration of a set of modeling tools, executable formalisms, analytical tools, and animation tools. the essential step is converting SysML-Based specifications into colored Petri nets through a conversion scheme proposed here. Such a paradigm permits rigorous static and dynamic system analysis, as well as formal verification of the behavior and functionality of the SysML-Based design. This paper also compares the capabilities of the proposed executable system architecting paradigm with other executable formalisms. Further, it discusses the basic principles of executable architecture specification and analysis for …

Anticipating U.S. Population-Level Health And Economic Impacts Using Discrete-Event Simulation To Guide Health Policy Decisions, Odette Reifsnider

All Dissertations

This dissertation presents two applications of discrete-event simulation (DES) to represent clinical processes: (1) a model to quantify the risk of the maternal obese and diabetic intrauterine environment influence on progression to adult obesity and diabetes, and (2) a model to evaluate health and economic outcomes of different smoking cessation strategies. The first application considers the public health impact of the diabetic and obese intrauterine environment's effect on the prevalence of diabetes and obesity across subsequent generations. We first develop a preliminary DES model to investigate and characterize the epidemiology of diabetes during pregnancy and birth outcomes related to maternal …

Using Discrete Event Computer Simulation To Analyze The Effects Of Proposed Changes To Personnel In A Hospital Medical Laboratory, Gerardo Morales

Theses and Dissertations - UTB/UTPA

A discrete event computer simulation is used to model a portion of the medical laboratory at Doctors Hospital at Renaissance in order to assess the current situation as well as to review the planed personnel changes. The area under observation is the section in which the processor(s) receive, label and distribute the patient samples. There are four cases modeled in the simulation: The main focus is to determine if one or two processors are needed per shift and if the high level of phone calls poses a significant delay to the processors’ workflow. The simulation results indicate that having two …