Computational Engineering Commons^™

A New Heuristic Algorithm For Accuracy And Computational Efficiency For Solving Minimum Cost Flow Problems, Timothy Michael Chávez

Computational Modeling & Simulation Engineering Theses & Dissertations

While the minimum cost flow (MCF) problems have been well documented in many publications, due to its broad applications, little or no effort has been devoted to explaining the algorithms for identifying loop formation and computing the θ value needed to solve MCF network problems. This paper proposes efficient numerical procedures and MATLAB computer implementation for computing the θ value. Furthermore, this paper also proposes a mixed heuristic, shortest path (SP) Chavez-Nguyen (or Chayen) Algorithm in Phase 1 (to obtain the basic feasible solution) and, either the conventional MCF or MATLAB’s built-in Linprog() function, in Phase 2 (to obtain the …

Gesture Based Control Of Semi-Autonomous Vehicles, Brian Sanders

Computational Modeling & Simulation Engineering Theses & Dissertations

The objective of this investigation is to explore the use of hand gestures to control semi-autonomous vehicles, such as quadcopters, using realistic, physics based simulations. This involves identifying natural gestures to control basic functions of a vehicle, such as maneuvering and onboard equipment operation, and building simulations using the Unity game engine to investigate preferred use of those gestures. In addition to creating a realistic operating experience, human factors associated with limitations on physical hand motion and information management are also considered in the simulation development process. Testing with external participants using a recreational quadcopter simulation built in Unity was …

Using Eye And Head Movements As A Control Mechanism For Tele-Operating A Ground-Based Robot And Its Payload, Kathryn C. Hicks

Computational Modeling & Simulation Engineering Theses & Dissertations

To date, eye and head tracking has been used to indicate users' attention patterns while performing a task or as an aid for disabled persons, to allow hands-free interaction with a computer. The increasing accuracy and the reduced cost of eye- and head-tracking equipment make utilizing this technology feasible for explicit control tasks, especially in cases where there is confluence between the visual task and control.

The goal of this research was to investigate the use of eye-tracking as a more natural interface for the control of a camera-equipped, remotely operated robot in tasks that require the operator to simultaneously …

Java Animated Software For Teaching The Frank-Wolfe Algorithm For Static Traffic Network Equilibrium, Zhi Li

Computational Modeling & Simulation Engineering Theses & Dissertations

The popular Frank-Wolfe (FW) algorithm for solving the network equilibrium problems plays an important role in transportation simulation. Not only has the basic Frank Wolfe algorithm been studied, but also other variations of the FW algorithm (such as Conjugate Frank Wolfe and Bi-Conjugate Frank Wolfe algorithms) have been extensively studied by the research communities.

In this work, the basic Frank Wolfe algorithm is re-visited for the purpose of developing a useful, user-friendly, and appealing Java computer animation for enhancing the teaching effectiveness of this fundamental transportation static network equilibrium algorithm. Since the shortest path (SP) algorithms (such as the well-known …

Discretized Agent-Based Model Of Infectious Disease Spread That Uses Contact Probability, Tyrell L. Gardner

Computational Modeling & Simulation Engineering Theses & Dissertations

This study uses contact probability in an agent-based model to simulate the spread of an infectious disease. In order to perform the study, the agent-based model must first be discretized into events. Each agent in the model is given its own infectious disease state machine taken from the Susceptible-Exposed-Infected-Recovered (SEIR) model. The agents move between squares in a grid environment where each square represents a group. Groups have a contact probability as an attribute that is used to predict whether an agent comes in close contact with another agent. The transitions between the states in the SEIR model are easily …

Parallel Implementations Of The Frank-Wolfe Algorithms For The Traffic Assignment Problem, Shawn Eugene Allen

Computational Modeling & Simulation Engineering Theses & Dissertations

Transportation planners seek to understand how to best invest limited resources for future transportation network development. The traffic assignment problem is one algorithm of great importance to planners because it provides insight into how traffic will flow within the network. The Frank-Wolfe algorithm is a traditional solution method for this optimization problem, but it has been characterized by its slow rate of convergence and poor computational performance. This thesis examines and implements several modern advancements in this algorithm which are designed to improve the rate of convergence.

In addition to algorithm changes, another method to improve the performance of an …

Using Real Property Layouts To Study The Foreclosure Contagion Effect In Real Estate With Agent-Based Modeling And Simulation, Daniele Vernon-Bido

Computational Modeling & Simulation Engineering Theses & Dissertations

Foreclosures in the United States increased sharply from 2007 to 2009. These foreclosures had a spillover effect on neighboring property values causing additional foreclosures. This is known as the foreclosure contagion effect.

Recent studies have quantified the discount attributed to foreclosure contagion using equation-based techniques. However, the discount varied between studies and markets. Further studies using agent-based modeling and simulation have demonstrated the relationship between the discounts, the time a foreclosure remains on the market, the prevailing interest rates and the average property values.

This study uses agent-based modeling and simulation (ABMS) to explore the differences that varying neighborhood densities …

A Multi-Configuration Display Methodology Incorporating Reflection For Real-Time Haptic-Interactive Virtual Environments, Mohammad F. Obeid

Computational Modeling & Simulation Engineering Theses & Dissertations

There is a natural need for real-time min-or reflection in many interactive virtual reality applications to achieve visuo-haptic collocation through optical reflection. Its use, however, calls for adjustments to the original model since a mirror reverses image characteristics. This thesis introduces a design and implementation of a generic configuration component for virtual environments that adjusts image characteristics and haptic interfaces to accommodate various display setups while preserving the correct orientation and properties of the original models in the graphical scene. Four different but related approaches were developed for image connection and are compared and contrasted against primary criteria. The haptic …

Measuring The Value Of Conceptual Modeling A Return On Investment (Roi) Analysis, Jeffrey Alan Brelsford

Computational Modeling & Simulation Engineering Theses & Dissertations

This thesis presents a method for calculating the return on investment (ROI) of conceptual modeling. Conceptual modeling as it relates to Modeling and Simulation (M&S) studies is a process that abstracts a model of a real or proposed system to be subsequently used for developing computer models. The conceptual modeling process is a critical constituent in an M&S project because it produces the central reference for building the computer model. Computer models require formal logic to carry out procedures, and consistent arguments in formal logic are crucial for the model to be useful. Not only does formal logic provide the …

Orientation-Invariant Ecg-Based Virtual Pathology Stethoscope Tracking For Standardized Patient Heart Auscultation, Nahom B. Kidane

Computational Modeling & Simulation Engineering Theses & Dissertations

Cardiac auscultation (CA), the act of listening to the heart sounds, is a critical physician's skill that provides substantial information for diagnosing many cardiovascular disorders; therefore, competent training can be a key for accurate and reliable diagnosis. The teaching of CA has been an area of recognized importance since the inception of the stethoscope. However, recent changes in health-care, such as limited student access to patients and higher reliance on competing technologies have made it challenging to teach bedside CA techniques.

Over the past few decades, standardized patients (SPs), individuals trained to portray real patients, have been widely used for …

Semi-Automatic Simulation Initialization By Mining Structured And Unstructured Data Formats From Local And Web Data Sources, Olcay Sahin

Computational Modeling & Simulation Engineering Theses & Dissertations

Initialization is one of the most important processes for obtaining successful results from a simulation. However, initialization is a challenge when 1) a simulation requires hundreds or even thousands of input parameters or 2) re-initializing the simulation due to different initial conditions or runtime errors. These challenges lead to the modeler spending more time initializing a simulation and may lead to errors due to poor input data.

This thesis proposes two semi-automatic simulation initialization approaches that provide initialization using data mining from structured and unstructured data formats from local and web data sources. First, the System Initialization with Retrieval (SIR) …

Design And Comparison Of Immersive Interactive Learning And Instructional Techniques For 3d Virtual Laboratories, Shuo Ren

Computational Modeling & Simulation Engineering Theses & Dissertations

Virtual reality (VR) as a learning environment plays an important role m engineering education. Utilizing the VR learning environment as a supplement to engineering-based laboratories is especially beneficial for students to prepare for the physical experiment and to grasp the experiment objectives and procedures. Such a methodology can also play a significant role in distance education.

This work presents the methodology design for the physical-to-virtual transformation of two undergraduate mechanical engineering laboratory experiments, namely the "Jet Impact Force on Vanes (Jet Force Lab)" and the "Elastic Test of a Beam in Pure Bending (Beam Bending Lab)" at Old Dominion University. …

Clearing Paths For Emergency Vehicles Using Shock Wave Theory And Vehicle-To-Vehicle Communication, Craig Austin Jordan

Computational Modeling & Simulation Engineering Theses & Dissertations

A new strategy to enable an EV to navigate through congestion at signalized intersections more efficiently has been developed and is presented in this thesis. The proposed strategy involves communicating control messages to vehicles to change their driving behavior and to traffic signals to change their timing plans so that EV s can proceed through congested intersections as quickly as possible. To achieve this, specific vehicles are instructed to hold their positions to create a split in the vehicle queue at a critical location in one lane. The split allows the EV to change lanes and proceed unimpeded at its …

A Multi-Paradigm Modeling Framework For Modeling And Simulating Problem Situations, Christopher James Lynch

Computational Modeling & Simulation Engineering Theses & Dissertations

Problem situations are problems whose specifications are not universally agreed upon making them a challenge to be modeled and simulated. Models of problem situations depart from the premise of well-defined problems, problems where stakeholders disagree, but also modelers' interpretations play a role in their design and computer implementation.

This thesis proposes a multi-paradigm modeling framework for modeling and simulating problem situations in order to explore the problem space of the problem situations and answer specific modeling questions.

The proposed framework implements the Modeling and Simulation (M&S) System Development Framework (MS-SDF), which is a methodology for modeling a problem situation while …

Health Nexus: A Serious Game Prototype For Prevention And Treatment Of Obesity And Diabetes, Joseph C. Miller

Computational Modeling & Simulation Engineering Theses & Dissertations

Electronic games are a prevalent phenomenon of American culture and entertainment. Serious games are video games that take advantage of games' intrinsic entertaining and challenging characteristics for serious purposes, such as education, training, advertisement, and political campaigns. A significant number of serious games have been developed for a variety of diverse purposes. The last few years have witnessed the inception and growth of motion sensing technologies for games, including Nintendo Wii, Sony PlayStation Move, and Microsoft Kinect. These motion sensing technologies usually require game players' physical body movement in order to perform and achieve in the games, such as playing …

A Google Earth-Based Framework For Visualization Of The Chesapeake Bay Operational Forecast System, Gary Lawson

Computational Modeling & Simulation Engineering Theses & Dissertations

For the persons who live near and travel the waters of the Chesapeake Bay, the data provided by the Chesapeake Bay Operational Forecast System (CBOFS) is invaluable. The information provided includes measurements and forecasts of surface wind velocity, water current velocity, salinity levels, water level, and temperature. Currently, this information is freely available on the CBQ_FS website hosted by the National Oceanographic and Atmospheric Administration (NOAA). It is offered as Nowcast, measured data, and Forecast data and is visualized using 2D images which describe a subset of the data in an easy to read chart. However, if the data were …

Architecture For A Flexible And Scalable Simulation Engine, Robert C. Holcomb Jr.

Computational Modeling & Simulation Engineering Theses & Dissertations

Simulation is used by many different industries to gain insight on actions and decisions that may be too dangerous or costly to perform in reality. Although the use of computers to assist with modeling and simulation has been studied for quite a while, computer infrastructure, hardware, and capabilities are changing at a rapid pace. Computer software once written is difficult and costly to change, especially in order to take advantage of the advances in computer hardware. This thesis focuses on the design and implementation of a software simulation architecture that allows flexibility in the modeling conducted and scalability in the …

Modeling The Contagion Effect Of Foreclosures Within The Real Estate Market By Use Of Agent-Based Modeling And Simulation, Marshall William Gangel

Computational Modeling & Simulation Engineering Theses & Dissertations

Over the last several years, the US financial and real estate markets have experienced a significant recession. During this downturn, the number of real estate foreclosures rose drastically. Recent studies have empirically demonstrated a reduction in real estate values due to foreclosures. The observed reduction in the average value of real estate properties has been labeled the foreclosure contagion effect. The foreclosure contagion effect impacts healthy neighboring properties that surround the foreclosed property as a function of time and distance.

This study uses an agent-based modeling and simulation (ABMS} approach to explore the contagion effect of foreclosures. For this research, …

Solving The Vehicle Re-Identification Problem By Using Neural Networks, Tanweer Rashid

Computational Modeling & Simulation Engineering Theses & Dissertations

Vehicle re-identification is the process by which vehicle attributes measured at one point on a road network are compared to vehicle attributes measured at another point in an effort to match vehicles without using any unique identifiers such as license plate numbers. A match is made if the two measurements are estimated to belong to the same vehicle. Vehicle attributes can be sensor readings such as loop induction signatures, or they can also be actual vehicle characteristics such as length, weight, number of axles, etc. This research makes use of vehicle length, travel time, axle spacing and axle weights for …

Determining The Utility Of Technology For Education, Brian Spencer Dillon

Computational Modeling & Simulation Engineering Theses & Dissertations

There is a substantial debate concerning the place of technology in education. This debate has been going on over every technology introduced through at least three millennia although the modern version takes place in journal articles. Technology, in the general sense, is already in the educational arena 1n ways which have become so commonplace that we hardly question them today. More modern technologies, however, meet perpetual resistance in achieving their potential. This paper calls into question the most recent trend in research and suggests a new research paradigm which focuses not only on student achievement, but on a variety of …

A Military Surge In Afghanistan -- Modeling A Focused Security Effort, Brent David Morrow

Computational Modeling & Simulation Engineering Theses & Dissertations

In October of 2001, the United States invaded Afghanistan and ousted the Taliban government. Since their overthrow, the Taliban has pieced together and waged an insurgency to retake Afghanistan. That insurgency has gained momentum and grown in strength while the United States NA TO counterinsurgency effort has decreased in size to about 55,000 troops in 2007. Many factors contribute to the insurgency inside of Afghanistan, from ethnic to economic factors to the failure of the central government. This research used a study of the current state of affairs in Afghanistan and agent-based modeling to determine whether a military troop surge …

Prostate Cancer Biomarker Identification: A Comparative Study, Wenjuan Jiang

Computational Modeling & Simulation Engineering Theses & Dissertations

With the current development of proteomics techniques, the discovery of potential molecular biomarkers for early detection of prostate cancer has been greatly improved. In this thesis, we implemented five classifiers including the support vector machine (SVM), Bayesian Classifier, Decision Tree, Random Forest and the Multilayer perceptron (MLP) to test their effectiveness in prostate cancer biomarker identification using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) tissue imaging data. The classifiers were utilized to discriminate cancer mass spectra from normal ones for the data collected at the Eastern Virginia Medical School (EVMS). There are 94 7 spectra from normal tissues and 27 from …

A Strategic Planning Decision Support Methodology In Emergency Department Preparedness For Mass Casualty Events, Adrian Spencer Benson

Computational Modeling & Simulation Engineering Theses & Dissertations

This study's objective is to design a strategic planning decision support methodology to improve Emergency Department (ED) preparedness for Mass Casualty Events (MCEs). This effort will enable hospital and medical strategic planners to evaluate alternatives which improve ED capacity. This comparative analysis illuminates the relative performance of alternatives involving three improvement scenarios for an ED, involving various increases in trauma bay, examination room, radiology, surgery, and recovery/observation study capacities. To illustrate this decision methodology, a Discrete Event Simulation (DES) was implemented in Arena, and used a mixture of Subject Matter Expert (SME) estimates and appropriate notional data. The design of …

A Framework For Using Modeling And Simulation-Based Methods In Support Of Project Management In A U.S. Department Of Defense Enterprise Architecture Framework Environment, Jose Leprout Bricio-Neto

Computational Modeling & Simulation Engineering Theses & Dissertations

The Enterprise Architecture, Analysis and Project Management (EA2PM) framework developed and proposed in this study enables better evaluation of the ability for enterprise architects, project managers and analysts to share system data using their own domain-specific software tools with a focus on the capability to automatically generate a discrete-event simulation model. EA2PM framework is based on applying a Knowledge Management (KM) construct to establish data and information boundaries, and developing a methodology that allows for high levels of traceability from system architecture's environmental factors through assessment of data and information mediation across domains within a KM system.

An application of …

An Agent-Based Combat Simulation Framework In Support Of Effect-Based And Net-Centric Evaluation, Robert Joseph Bowen

Computational Modeling & Simulation Engineering Theses & Dissertations

The use of information technologies (IT) and information networks has proliferated in industry as a method to achieve competitive advantage. The U.S. Military and its allies, in recent years, have employed IT to improve the way they conduct operations, speed decision making, and increase the span of control of commanders. This has resulted in a fundamental shift in the way military commanders employ combat units today. These (Information Age) forces no longer have to be able to see each other or even communicate directly in order to synchronize maneuvers. Dispersion is now favored over mass, relying on the IT network …

Modeling Geographic Population Dispersion Utilizing Geospatial Information System Environment Agents In An Agent Based Model, Karl D. Liebert

Computational Modeling & Simulation Engineering Theses & Dissertations

New capabilities in agent based model (ABM) environments are opening the door to the creation of ABM that may incorporate high-quality, real world environment data in the form of Geospatial Information System (GIS) files . In the past, GJS environments were only possible through extensive software development efforts focused on specific model applications.

This thesis explores the value and issues of using GIS data to provide an ABM environment. It examines the ability of ABM development environments (DE) to support GIS environment data. The selected ABM DE is then used to model population behavior in an environment defined by authoritative …

Investigation Of A Validation Technique For The Registration Of 3d Points Directly To Subjects With Pectus Excavatum, Taryn Tacosa Cuper

Computational Modeling & Simulation Engineering Theses & Dissertations

Pectus excavatum (PE) is a congenital deformity that results in a "caved in" appearance of the chest wall. The cause of this condition is unknown, but research suggests that an in vivo investigation of the biomechanical properties of the costal cartilages of subjects with PE may offer insight. Force and deflection measurements are proposed as a way to obtain this data; however, accurate location of cartilage from the skin level would be required for such an effort. Given the multiple potential sources of error with this process, a validation procedure to ensure the appropriateness of the findings must be developed; …

Evaluation Of The Applicability Of Jc3iedm Based Information Exchange Standardization Efforts To Link-16 Based Systems, Anthony Devivi

Computational Modeling & Simulation Engineering Theses & Dissertations

Command and Control (C2) systems are critical components in decision-making systems in both the military and civilian domains. These systems act as the data evaluation and dissemination tools for larger Command, Control, Computer, Communication, Intelligence, Surveillance, and Recognizance (C4ISR) systems. Typical C2 systems accept a wide variety of inputs from many sources such as radars, weapons systems, simulators, operators, and other C2 systems. The C2 system processes the input data and presents to the user information with which decisions are made. The C2 system also determines what information should be translated and disseminated to other C2 platforms.

The basis for …

Simulation To Augment Standardized Patients In Obstetric Ultrasound Training, Scott Richard Guirlinger

Computational Modeling & Simulation Engineering Theses & Dissertations

Standardized patients are actors used in medical training to teach and eval11atc clinical skills of students prior to their using these skills on an actual patient. Augmented Reality is a relatively new technology that can be used to augment standardized patients with abnonnalitie8 and pathologies that they cannot portray themselves as normal healthy human beings. In our project, we sought to augment standardized patients with a 12-week- old fetus in order to train and possibly evaluate medical students and professionals in performing obstetric ultrasound procedures and interpreting the corresponding ultrasound image results.

The software library ARToolkit provided the framework for …

Integrating Game Technology And Discrete Event Simulation To Analyze Mass Casualty Scenarios, Jason Loveland

Computational Modeling & Simulation Engineering Theses & Dissertations

In the last 10 years, video games have become complex simulation environments with high resolution 3D graphics enabled by powerhouse rendering engines, multi-player client server networks, user friendly displays and graphical user interface , while remaining relatively inexpensive. There is a critical need for systems engineering analysis and rapid trade studies due to changes in operations caused by current events such as terrorist attacks, asymmetric threats, natural disasters, etc. Modem games provide a unique way to visualize and interact with these complex environments, scenarios, missions, and operations. A discrete event simulator (DES) provides an environment to model system architecture behavior, …