Engineering Commons^™

Study Of Same-Lane And Inter-Lane Gvw Correlation, Bernard Enright, Eugene J. O'Brien, Colin C. Caprani

Conference papers

The methodology used is to generate a number of years of simulated traffic and to use extreme value statistics to predict more accurately the characteristic loading for a given bridge. The parameters and probability distributions used in the Monte Carlo simulation must be based on observed sample traffic data. Some previous studies have made unsubstantiated assumptions regarding correlation between the Gross Vehicle Weights (GVW) of trucks in the same lane, or between trucks in adjacent, same-direction lanes. For this paper, an extensive database of Dutch Weigh-in-Motion data is analysed. Data are collected from two same-direction lanes and are time-stamped to …

A Dynamic Heuristic For The Stochastic Unrelated Parallel Machine Scheduling Problem, Jean-Paul Arnaout, Ghaith Rabadi, Ji Hyon Mun

Engineering Management & Systems Engineering Faculty Publications

This paper addresses the problem of batch scheduling in an unrelated parallel machine environment with sequence dependent setup times and an objective of minimizing the total weighted mean completion time. The jobs' processing times and setup times are stochastic for better depiction of the real world. This is a NP-hard problem and in this paper, new heuristics are developed and compared to existing ones using simulation. The results and analysis obtained from the computational experiments proved the superiority of the proposed algorithm PMWP over the other algorithms presented.

Requirements Gathering For Simulation, John Ryan, Cathal Heavey

Conference papers

This paper discusses the current shortfalls in support for the pre-coding phases of a discrete event simulation project. The paper then presents a process modelling technique, Simulation Activity Diagrams (SADs), developed to specifically support the initial requirements gathering phases of a simulation project. The paper concludes with an outline of proposed future developments to the modelling technique.

A Labview-Based Virtual Instrument For Engineering Education: A Numerical Fourier Transform Tool, Levent Sevgi̇, Çağatay Uluişik

Turkish Journal of Electrical Engineering and Computer Sciences

Engineering is based on practice. The minima of this practice should be given during the university education. This has become more and more comprehensive and expensive parallel to high-technology devices developed and presented to societies. Computers, microprocessor-based devices, programmable systems on Chip (PSoC), etc., make engineering education not only very complex but interdisciplinary as well. Building undergraduate labs has become more and more expensive if only physical experimentation and hands-on training are targeted. On the other hand, simple, comparatively much cheaper software may turn a regular personal computer (PC) into a virtual lab. The key question therefore is, to establish …

Statistical Computation For Extreme Bridge Traffic Load Effects, Colin C. Caprani, E. J. O'Brien

Conference papers

The maintenance of highway infrastructure constitutes a major expenditure in many countries. This cost can be reduced significantly by minimizing the repair or replacement of highway bridges. In the assessment of existing bridges, the strength estimate tends to be more accurate than that of traffic loading, due to the more variable nature of loading. Recent advances in the statistical analysis of highway bridge traffic loading have resulted in more accurate forecasts of the actual loading to which a bridge is subject. While these advances require extensive numerical computation, they can significantly improve the accuracy of the calculation. This paper outlines …

Effect Of Operator Control Configuration On Unmanned Aerial System Trainability, John Neumann

Electronic Theses and Dissertations

Unmanned aerial systems (UAS) carry no pilot on board, yet they still require live operators to handle critical functions such as mission planning and execution. Humans also interpret the sensor information provided by these platforms. This applies to all classes of unmanned aerial vehicles (UAV's), including the smaller portable systems used for gathering real-time reconnaissance during military operations in urban terrain. The need to quickly and reliably train soldiers to control small UAS operations demands that the human-system interface be intuitive and easy to master. In this study, participants completed a series of tests of spatial ability and were then …

Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems, Matthew Rhodes

Electronic Theses and Dissertations

Laser tracking systems are an important aspect of the NASA space program, in particular for conducting research in relation to satellites and space port launch vehicles. Often, launches are conducted at remote sites which require all of the test equipment, including the laser tracking systems, to be portable. Portable systems are more susceptible to environmental disturbances which affect the overall tracking resolution, and consequently, the resolution of any other experimental data being collected at any given time. This research characterizes the optical coupling between two systems in a Mobile Experimental Laser Tracking system and evaluates several control solutions to minimize …

Developing Microscopic Toll Plaza Model Using Paramics, Nezamuddin Nezamuddin

Electronic Theses and Dissertations

Simulation modeling is the most cost-effective way of studying real life transportation problems, either existing or anticipated, without disturbing the balance of the transportation system. There is a vast suite of simulation models available in market, ready to choose from macroscopic, mesoscopic, or microscopic in nature, to study different transportation system elements like freeways, highways, signalized and un-signalized intersections. However, most of these network simulation models, like PARAMICS, VISSIM, CORSIM … etc, do not come readily available with built in toll plaza models. On the other hand, many researchers have independently developed toll plaza models, which can only model an isolated …

A Hybrid Simulation Methodology To Evaluate Network Centricdecision Making Under Extreme Events, Sergio Quijada

Electronic Theses and Dissertations

Currently the network centric operation and network centric warfare have generated a new area of research focused on determining how hierarchical organizations composed by human beings and machines make decisions over collaborative environments. One of the most stressful scenarios for these kinds of organizations is the so-called extreme events. This dissertation provides a hybrid simulation methodology based on classical simulation paradigms combined with social network analysis for evaluating and improving the organizational structures and procedures, mainly the incident command systems and plans for facing those extreme events. According to this, we provide a methodology for generating hypotheses and afterwards testing …

The Effectiveness And Criteria For Placement Of Raised Pavement Markers (Synthesis Study), Yi Jiang

JTRP Technical Reports

Raised pavement markers (RPM) are used in highway centerlines and edge lines as a traffic safety measure to provide more positive guidance for motorists in inclement weather and low light conditions. They have been widely applied by highway agencies as delineation treatments to improve driver preview distances. The Indiana Department of Transportation (INDOT) has installed RPMs on selected roadway sections primarily as position guidance devices in order to better guide drivers in night conditions. In Indiana, RPMs are installed on all interstate highways and multilane divided highways. However, RPMs are used on only a few of the Indiana’s two-lane highways. …

Simulation Model For Assessing Transient Performance Of Capacitive Voltage Transformers, I. Sule, Ganesh K. Venayagamoorthy, U. O. Aliyu

Electrical and Computer Engineering Faculty Research & Creative Works

In determining the correct operation of relays of a protection scheme, proper representation of instrument transformers and their behavior in conditions where there can be transient is very critical. This paper presents a simulation model for assessing the transient performance of capacitive voltage transformers (CVTs). In order to test the validity of the developed model, four CVT operational conditions are considered using field data collected from one of the Nigerian electric utility 330/132/33 kV substations. The model simulation results revealed various configuration performance responses that could affect relay protection schemes to different degrees. As expected, the CVT responses showed that …

An (R,S)-Inventory Policy For Winter Maintenance Materials For The State Of Ohio, Nicholas Andrew Brown

Browse all Theses and Dissertations

Winters in Ohio mean snow and ice, and with snow and ice come treacherous roads. Roads that become treacherous or impassable cost the state economically and socially. Thus to prevent this from happening road crews are out spreading salt on the roads before, during, and after a storm to promote safe travel. To provide the amount of salt needed to all counties of Ohio; individual counties stock up during the summer and fall, re-order to maintain inventory through the winter time, and finally allowing inventories to reduce towards the end of winter. During a mild winter salt not used and …

A Holistic Usability Framework For Distributed Simulation Systems, Jeffrey Dawson

Electronic Theses and Dissertations

This dissertation develops a holistic usability framework for distributed simulation systems (DSSs). The framework is developed considering relevant research in human-computer interaction, computer science, technical writing, engineering, management, and psychology. The methodology used consists of three steps: (1) framework development, (2) surveys of users to validate and refine the framework, and to determine attribute weights, and (3) application of the framework to two real-world systems. The concept of a holistic usability framework for DSSs arose during a project to improve the usability of the Virtual Test Bed, a prototypical DSS, and the framework is partly a result of that project. …

Technical Support For Development Of An Attic Simulation Model For The California Energy Commission, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The California Energy Commission (CEC) is developing a new attic simulation model for assessing residential energy performance within its Title 24 residential compliance methodology. Within this project, we are providing technical support to assist Bruce Wilcox and CEC in development of the model based on Florida Solar Energy Center (FSEC) experience with similar models. We assisted the effort by using data from FSEC instrumented facilities to help verify the eventual simulation. We also outlined critical issues for modeling with the development of the simulation. Given the importance of attic ventilation, we are also conducting new studies of varied ventilation rates …

Integrating Value Stream Mapping And Simulation, Michelle E. Scullin

Theses and Dissertations

An important principle in Lean manufacturing, value stream mapping (VSM) can be helpful in understanding how process flow and information flow affect each other. A VSM is a static picture of a process that allows the user to see where value is added into the value stream. Simulation is used to evaluate the behavioral issues of processes. In a manufacturing realm this means simulation shows how each operation affects other operations so determinations can be made about where bottlenecks or other problems exist in the process. Theoretically, the integration of VSM and Simulation can aide in process improvement by showing …

A Flexible Infrastructure For Multi-Agent Systems, Gerrit Addison N Sorensen

Theses and Dissertations

Multi-Agent coordination and control has been studied for a long time, but has recently gained more interest because of technology improvements allowing smaller, more versatile robots and other types of agents. To facilitate multi-agent experiments between heterogeneous agents, including robots and UAVs, we have created a test-bed with both simulation and hardware capabilities. This thesis discusses the creation of this unique, versatile test-bed for multi-agent experiments, also a unique graph creation algorithm, and some experimental results obtained using the test-bed.

Finite Element Analysis Of Covered Microstents, Linxia Gu, Swadeshmukul Santra, Robert A. Mericle, Ashok V. Kumar

Department of Mechanical and Materials Engineering: Faculty Publications

Currently available neuroendovascular devices are inadequate for effective treatment of many wide-necked or fusiform intracranial aneurysms and intracranial carotid-cavernous fistulae (CCF). Placing a covered microstent across the intracranial aneurysm neck and CCF rent could restore normal vessel morphology by preventing blood flow into the aneurysm lumen or CCF rent. To fabricate covered microstents, our research group has developed highly flexible ultra thin (~150 μm) silicone coverings and elastomerically captured them onto commercially available metal stents without stitching. Preliminary in vivo studies were conducted by placing these covered microstents in the common carotid artery of rabbits. The feasibility of using covered …

Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee

Dissertations

Three-phase flow of solid-gas suspension with liquid spray is found in many industrial applications, including fluidized catalytic cracking in petroleum refinery process, and wet scrubbing process. This dissertation study is aimed to understand the gas-solid-liquid three-phase flow structure, phase interactions and transport in a gas-solid circulating fluidized bed where an evaporating cross-flow liquid spray jet from a rectangular nozzle with a fan angle is injected. The investigation is based on both numerical and experimental approaches. The numerical study is for detailed field descriptions of the flow structure, phase interaction and distributions whereas the experimental study is for simulation validations. The …

Development And Application Of A New Modeling Technique For Production Control Schemes In Manufacturing Systems, Bashar Hafez Sader

Theses and Dissertations

This dissertation presents dynamic system models of continuous manufacturing systems based on analogies with electrical systems. The developed modeling technique has the capability to explicitly specify production control schemes including control points, material and information flow paths, and logical operations. The model provides standard graphical representations and governing equations to describe both the steady state and transient responses of continuous manufacturing systems. For deterministic systems, these equations can be solved to get closed-form solutions. For stochastic systems, numerical solutions can be obtained for any probabilistic distribution. The electrical analogs provide an excellent tool to model control signals and logical operations. …

A Tool Wear Comparative Study In Turning Versus Computer Simulation In 1018 Steel, Woodrow D. Miner

Theses and Dissertations

The material removal process uses cutting tools in order to produce the desired shape of the workpiece. Tool wear has been a problem for cutting tools, since cutting tools wear and break. Research has been accomplished in the tool wear field for tool life and more recently tool wear. The computer generation has created a method to simulate the material removal process. These computer simulations model the cutting tool reaction with the workpiece. Many of the simulation models use finite element analysis to calculate the reaction of the cutting tool. Different finite element models are being used throughout the world …

Pulse Regulation Control Technique For Integrated High-Quality Rectifier-Regulators, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

The pulse regulation control scheme is presented and applied to the boost integrated flyback rectifier/energy storage dc/dc (BIFRED) converter as the most popular member of the integrated high-quality rectifier-regulators (IHQRR). In contrast to the conventional control techniques, the principal idea of pulse regulation is to regulate the output voltage using a series of high- and low-power pulses generated by the current of the input inductor, which is operating in discontinuous conduction mode (DCM). Analysis of the BIFRED converter operating in DCM is presented. Fundamentals of pulse regulation as well as its stability analysis and the estimation of the output voltage …

Robust Control Techniques For State Tracking In The Presence Of Variable Time Delays, Jarrett Goodell, Marc Compere, Miguel Simon, Wilford Smith, Ronnie Wright, Mark Brudnak

Publications

In this paper, a distributed driver-in-the-Ioop and hardware-in-the-Ioop simulator is described with a driver on a motion simulator at the U.S. Army TARDEC Ground Vehicle Simulation Laboratory (GVSL). Realistic power system response is achieved by linking the driver in the GVSL with a full-sized hybrid electric power system located 2,450 miles away at the TARDEC Power and Energy Systems Integration Laboratory (P&E SIL), which is developed and maintained by Science Applications International Corporation (SAIC). The goal is to close the loop between the GVSL and P&E SIL over the Internet to provide a realistic driving experience in addition to realistic …

Development Of A Process Modelling System For Simulation, John Ryan

Other resources

This thesis details the development of a process modelling technique to aid a simulation model developer during the requirements gathering and conceptual modelling phases of a simulation project.

There are a number of process modelling techniques available that are capable of being used during such phases of a simulation project, however there is currently a lack of process modelling techniques developed specifically to aid a simulation model developer in capturing, representing and communicating information and systems issues to persons involved in the operation of discrete systems under investigation.

A detailed review of the literature related to techniques capable of supporting …

Enhancing Erp System’S Functionality With Discrete Event Simulation, Young Moon, Dinar Phatak

Mechanical and Aerospace Engineering - All Scholarship

Purpose – To develop a methodology to augment enterprise resource planning (ERP) systems with the discrete event simulation’s inherent ability to handle the uncertainties.

Design/methodology/approach – The ERP system still contains and uses the material requirements planning (MRP) logic as its central planning function. As a result, the ERP system inherits a number of shortcomings associated with the MRP system, including unrealistic lead-time determination. The developed methodology employs bi-directional feedback between the non-stochastic ERP system and the discrete event simulation model until a set of converged lead times is determined.

Findings – An example of determining realistic production lead-time data …

Control System Design And Simulation Of Spacecraft Formations, Daniel Dyer

Master's Theses - Daytona Beach

The objective of this thesis is to analyze an effective control scheme for a formation of spacecraft, implement that control, and provide a 3-D simulation. The thesis first summarizes the progress made in formation flight control schemes and then provides a theoretical framework for the control system design. Using established control design techniques, feedback laws are constructed to control both rotational and translational motion of a group of spacecraft. Computer simulations are carried out using Matlab to generate the ephemeris and attitude data, which are exported to Satellite Tool Kit (STK) to create animations. The process by which Matlab is …

Right Turn Split: A New Design To Alleviate Weaving On Arterial Streets, Khaled Shaaban

Electronic Theses and Dissertations

While weaving maneuvers occur on every type of roadway, most studies have focused on freeway maneuvers. Weaving occurring on non-freeway facilities, such as arterial streets, can cause significant operational problems. Arterial streets weaving typically occur when vehicles coming from a side street at an upstream intersection attempt to enter the main street from one side to reach access points on the opposite site at a downstream intersection by crossing one or more lanes. This dissertation investigates the type of problems occurring on arterial streets due to the weaving movements and recommends a new design to alleviate weaving on arterial streets. …

Optimal Operating Strategy For Wells With Downhole Water Sink Completions To Control Water Production And Improve Performance, Ozan Arslan

LSU Doctoral Dissertations

Downhole water sink (DWS) technology is an alternative to conventional limited-entry completions to control water production in wells with bottom water drive. DWS wells comprise two completions: the bottom completion produces water and keeps the top completion open to oil inflow. The system performance depends on careful manipulation of the top and bottom rates to maximize oil productivity and produce oil-free water from the bottom completion. Conventional nodal analysis cannot provide a solution for DWS wells because the critical rates for water coning change with water drainage rate. A reservoir simulator is used to model two-phase flow to the dual …

Experimental And Numerical Study Of Feeding Channel In Proton Exchange Membrane Fuel Cell, Abul Bashar Mahmud Hasan

LSU Master's Theses

The performance of a Proton Exchange Membrane Fuel Cell (PEMFC) using different feeding configurations has been studied, with a focus on the water flooding due to electrochemical reaction. Feeding channel or Bipolar plate in Proton Exchange Fuel Cell is a dominating part. As feeding channel keeps direct contact with the gas diffusion layer, it helps efficiently supplying fuel and air into the gas diffusion layer for efficient production of electricity. Experimental data have been taken at hydrogen flow rates of 20,40,60,80,100 sccm for various bipolar plate arrangements. Three bipolar plates, namely serpentine, straight channel and interdigitated designs, were arranged in …

Simulation And Economic Evaluation Of Coal Gasification With Sets Reforming Process For Power Production, Zachary Hoffman

LSU Master's Theses

Increasing natural gas prices have raised interest in alternate energy resources. Popular belief in the connection between carbon dioxide emissions and global warming has motivated the search for a technique to isolate carbon dioxide from combustion stack gases. Coal gasification with SETS reforming has been proposed as a solution to both of these issues in that it provides an alternate energy source and 100% carbon dioxide sequestration. The purpose of this research is to simulate this process using AspenPlus to perform the rigorous material and energy balances. The results of this simulation are used to carry out a complete economic …

Aeration Strategies And Fan Cost Comparisons For Wheat In Mid-South Production Regions, Thomas C. Bridges, Michael D. Montross, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

Numerous factors influence the sizing of aeration fans for summer-harvested crops. Thirty years of weather data for Lexington, Kentucky, were analyzed and the cost of aeration was compared for two axial fans (afan1, afan2) and one centrifugal fan (cfan1). Aeration costs were defined as the sum of the following components: the cost of owning the fan, the cost of electricity for operating the fan, a cost for wheat shrinkage during aeration, and a cost for dry matter loss (DML). The fans were selected to deliver airflow rates of approximately one, two, and three times the recommended aeration rate of 0.11 …