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Articles 61 - 90 of 90

Full-Text Articles in Automotive Engineering

Competencies Related To Marine Mechatronics Education, Vukica M. Jovanovic, Petros J. Katsioloudis, Mileta Tomovic, Thomas B. Stout Jan 2016

Competencies Related To Marine Mechatronics Education, Vukica M. Jovanovic, Petros J. Katsioloudis, Mileta Tomovic, Thomas B. Stout

Engineering Technology Faculty Publications

Recent changes in the needs of the military have caused the U.S. Navy to spend more time out to sea. Longer deployments limit the time available for performing maintenance and for training their technicians. The Navy is also steadily reducing the number of sailors manning each vessel, therefore requiring more automated systems to keep the ships at sea and in total readiness. To meet this need, industrial automation systems are being investigated as replacements and upgrades for the military systems that have been used for years in warship designs. This will require ship repair partners, both military and civilian, to …


Design Of Timing Circuit For Fuel Injection Conversion And Development Of Laboratory To Analyze Engine Performance Using A Dynamometer, Aditi Jayram Limaye Apr 2015

Design Of Timing Circuit For Fuel Injection Conversion And Development Of Laboratory To Analyze Engine Performance Using A Dynamometer, Aditi Jayram Limaye

Mechanical & Aerospace Engineering Theses & Dissertations

A fundamental facility was built to analyze some of the basic parameters involved in engine performance, namely torque and power output of the engine. One of the objectives was to convert a carbureted engine into a fuel injection or (Fl) engine. This was achieved by designing and creating a timing circuit that is required to trigger the electronic fuel injector or (EFI). The facility was designed around a dynamometer and a fuel delivery system; that provided a specialized tool to analyze engines and injectors.

The results from the carbureted experiments and the FI experiments were compared to the rated specifications …


Addressing New Skills Needed For The Automotive Industry Through A Motorsports Educational Pathway, Vukica M. Jovanovic, Mileta M. Tomovic, Alok K. Verma, Nathan Luetke, Steve Branch Jan 2015

Addressing New Skills Needed For The Automotive Industry Through A Motorsports Educational Pathway, Vukica M. Jovanovic, Mileta M. Tomovic, Alok K. Verma, Nathan Luetke, Steve Branch

Engineering Technology Faculty Publications

The automotive industry has higher-skilled positions available that need engineers and engineering technologists qualified and capable to work in a high-paced, advanced manufacturing sector. Various educational programs across the country offer programs related to the motorsports area at the Associate of Science level. There are also various articu-lation agreements that enable students to continue their education to the baccalaureate level. These programs try to fill in the gap related to the skills shortage in systems and new design methods and processes. The main strength of such educational pathways is that students, who are trained to work as technicians with an …


Human System Engineering Applications From Distracted Driving Simulations, Holly A.H. Handley, Cansu Kandemir, S. Long (Ed.), E.-H. Ng (Ed.), C. Downing (Ed.) Jan 2014

Human System Engineering Applications From Distracted Driving Simulations, Holly A.H. Handley, Cansu Kandemir, S. Long (Ed.), E.-H. Ng (Ed.), C. Downing (Ed.)

Engineering Management & Systems Engineering Faculty Publications

Most of the studies to explore the impact of distracted driving have been descriptive in nature; i.e. the research is conducted in naturalistic settings to evaluate the performance of the driver with and without distracters. However simulation models can also be used that predict the workload for driving tasks. Using concepts from process modeling, baseline models of driving tasks can be created for different driving sequences that include the associated fine motor, visual and cognitive human resources. These models can then be used to evaluate incidents of workload overload caused by different distracters, from both the internal and external vehicle …


Lessons In On-Campus And Distance Learning Delivery Of An Introductory Naval Architecture Course, Jennifer G. Michaeli Jan 2014

Lessons In On-Campus And Distance Learning Delivery Of An Introductory Naval Architecture Course, Jennifer G. Michaeli

Engineering Technology Faculty Publications

This paper describes the author’s experiences in multi-mode (face-to-face and online) delivery of an introductory-level course on the topic of Naval Architecture geared towards anaudience of engineering and engineering technology undergraduate students with no previousmaritime background. The goal of this course is to expose talented undergraduate engineering students to the marine industry and to prepare those interested in pursing a career in this field with an introductory understanding of the complex nature of designing and building ships and other marine vessels. This course was offered in Spring 2013 and Fall 2013 to a group of engineering and engineering technology students. …


Use Of A Rolling Road System In Crosswind Conditions, Mau-Kuo Chen Jul 2013

Use Of A Rolling Road System In Crosswind Conditions, Mau-Kuo Chen

Mechanical & Aerospace Engineering Theses & Dissertations

Wind tunnel testing continues to play an important role in vehicle aerodynamic development. Accurate results are strongly associated with whether the wind tunnel can closely simulate the on-road conditions, including the Reynolds number and all boundary conditions. Rolling road systems (or moving belts) have been a successful tool for many auto makers and racing teams to simulate the relative motion between the stationary vehicle model and the floor in the test section. The mechanism of the rolling road system is simple, but how it affects the adjacent flow field and how this flow interacts with the flow underneath the vehicle …


Tdma Slot Reservation In Cluster-Based Vanets, Mohammad Salem Almalag Apr 2013

Tdma Slot Reservation In Cluster-Based Vanets, Mohammad Salem Almalag

Computer Science Theses & Dissertations

Vehicular Ad Hoc Networks (VANETs) are a form of Mobile Ad Hoc Networks (MANETs) in which vehicles on the road form the nodes of the network. VANETs provide several services to enhance the safety and comfort of drivers and passengers. These services can be obtained by the wireless exchange of information among the vehicles driving on the road. In particular, the transmission of two different types of messages, safety/update and non-safety messages.

The transmission of safety/update message aims to inform the nearby vehicles about the sender's current status and/or a detected dangerous situation. This type of transmission is designed to …


The Effects Of External Motivation And Real-Time Automated Feedback On Speeding Behavior In A Naturalistic Setting, Ian J. Reagan, James P. Bliss, Ron Van Houten, Bryan W. Hilton Jan 2013

The Effects Of External Motivation And Real-Time Automated Feedback On Speeding Behavior In A Naturalistic Setting, Ian J. Reagan, James P. Bliss, Ron Van Houten, Bryan W. Hilton

Psychology Faculty Publications

Objective: In this field experiment, the authors tested an alerting system and a monetary incentive system with the objective of reducing speeding more than 5 mph faster than the posted speed limit.

Background: Speeding is a factor in a significant number of traffic fatalities. The systems tested in this project have been evaluated outside but not within the United States. These studies indicated that similar systems led to reductions in speeding.

Method: For this study, eight vehicles were instrumented such that vehicle speed and speed limits were linked in real time. A total of 50 participants drove assigned vehicles for …


Modeling, Identification, Validation And Control Of A Hybrid Maglev Ball System, Ahmed Elhussein E. Mekky Jul 2012

Modeling, Identification, Validation And Control Of A Hybrid Maglev Ball System, Ahmed Elhussein E. Mekky

Mechanical & Aerospace Engineering Theses & Dissertations

In this thesis, the electrodynamics of a single axis hybrid electromagnetic suspension Maglev system was modeled and validated by applying it to a single axis hybrid maglev ball experiment. By exploring its linearized model, it was shown that the single axis hybrid Maglev ball has inherently unstable dynamics. Three control scenarios were explored based on the linearized model; (1) Proportional, Deferential (PD) control, (2) Proportional, Deferential, Integral (PID) and (3) PID controller with pre-filtering. This thesis has shown that a PID controller with a pre-filtering technique can stabilize such a system and provide a well-controlled response.

A parametric system identification …


An Analysis Of Factors Affecting The Effective Use Of Knowledge Management In Counter Improvised Explosive Device (C-Ied) Operations, Umit Gencer, Rafael E. Landaeta, Resit Unal, C. Ariel Pinto, Gokay Sursal Jan 2012

An Analysis Of Factors Affecting The Effective Use Of Knowledge Management In Counter Improvised Explosive Device (C-Ied) Operations, Umit Gencer, Rafael E. Landaeta, Resit Unal, C. Ariel Pinto, Gokay Sursal

Engineering Management & Systems Engineering Faculty Publications

Improvised Explosive Device (IED) is a weapon of choice and is likely to remain a major component of the Global War on Terrorism. It is critical that gaps in knowledge transfer are quickly addressed in order to more effectively equip personnel to counter IED (C-IED) threat. Therefore, the military must analyze the current Knowledge Management (KM) programs in C-IED arena in order to maximize transfer of knowledge derived from experience and skill to staffs and finally to commanders. This study investigates the factors that influence effective use of KM in C-IED operations in the military. The study suggests that effective …


Project-Risk Management And Decision Analysis In Maritime Maintenance And Repair, Michael C. Plumb, C. Ariel Pinto, Rafael Landaeta, Resit Unal, Thomas Murphy Jan 2012

Project-Risk Management And Decision Analysis In Maritime Maintenance And Repair, Michael C. Plumb, C. Ariel Pinto, Rafael Landaeta, Resit Unal, Thomas Murphy

Engineering Management & Systems Engineering Faculty Publications

The purpose of this paper is to provide insights regarding the implementation of using Project Risk Management (PRM) and Decision Analysis (DA) in managing projects for complex systems such as maritime vessels. The PRM approach apprehends many forms of risk both internal and external within a given project and assists the manager in determining the level of importance of each individual project phase and component to optimize project success. Ship Maintenance and Repair project decision-making requires that risk management and risk analysis techniques be applied in order to guide management in making better decisions to meet ship service life perspective. …


A Framework For Dynamic Traffic Monitoring Using Vehicular Ad-Hoc Networks, Mohammad Hadi Arbabi Jul 2011

A Framework For Dynamic Traffic Monitoring Using Vehicular Ad-Hoc Networks, Mohammad Hadi Arbabi

Computer Science Theses & Dissertations

Traffic management centers (TMCs) need high-quality data regarding the status of roadways for monitoring and delivering up-to-date traffic conditions to the traveling public. Currently this data is measured at static points on the roadway using technologies that have significant maintenance requirements. To obtain an accurate picture of traffic on any road section at any time requires a real-time probe of vehicles traveling in that section. We envision a near-term future where network communication devices are commonly included in new vehicles. These devices will allow vehicles to form vehicular networks allowing communication among themselves, other vehicles, and roadside units (RSUs) to …


Interface Circuit For A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors, Ren Wang Jul 2011

Interface Circuit For A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors, Ren Wang

Mechanical & Aerospace Engineering Theses & Dissertations

This research work presents the design, theoretical analysis, fabrication, interface electronics, and experimental results of a Silicon-On-Insulator (SOI) based Multiple-Beam Tuning-Fork Gyroscope (MB-TFG). Based on a numerical model of Thermo-Elastic Damping (TED), a Multiple-Beam Tuning-Fork Structure (MB-TFS) is designed with high Quality factors (Qs) in its two operation modes. A comprehensive theoretical analysis of the MB-TFG design is conducted to relate the design parameters to its operation parameters and further performance parameters. In conjunction with a mask that defines the device through trenches to alleviate severe fabrication effect on anchor loss, a simple one-mask fabrication process is employed to implement …


Data Aggregation And Dissemination In Vehicular Ad-Hoc Networks, Khaled Ibrahim Apr 2011

Data Aggregation And Dissemination In Vehicular Ad-Hoc Networks, Khaled Ibrahim

Computer Science Theses & Dissertations

Vehicular Ad-Hoc Networks (VANETs) are a fast growing technology that many governments and automobile manufacturers are investing in to provide not only safer and more secure roads, but also informational and entertainment-based applications for drivers. The applications developed for VANETs can be classified into multiple categories (safety, informational, entertainment). Most VANET applications, regardless of their category, depend on having certain vehicular data(vehicular speed, X position and Y position) available. Although these applications appear to use the same vehicular data, the characteristics of this data (i.e., amount, accuracy, and update rate) will vary based on the application category. For …


Exploring The Effects Of Cooperative Adaptive Cruise Control In Mitigating Traffic Congestion, Georges M. Arnaout Apr 2011

Exploring The Effects Of Cooperative Adaptive Cruise Control In Mitigating Traffic Congestion, Georges M. Arnaout

Engineering Management & Systems Engineering Theses & Dissertations

The aim of this research is to examine the impact of CACC (Cooperative Adaptive Cruise Control) equipped vehicles on traffic-flow characteristics of a multilane highway system. The research identifies how CACC vehicles affect the dynamics of traffic flow on a road network and demonstrates the potential benefits of reducing traffic congestion due to stop-and-go traffic conditions. An agent-based traffic simulation model is developed specifically to examine the effect of these intelligent vehicles on the traffic flow dynamics. Traffic performance metrics characterizing the evolution of traffic congestion throughout the road network, are analyzed. Different CACC penetration levels are studied.

The positive …


Drag Reduction Of A Modern Straight Truck, Drew Landman, Matthew Cragun, Mike Mccormick, Richard Wood Jan 2011

Drag Reduction Of A Modern Straight Truck, Drew Landman, Matthew Cragun, Mike Mccormick, Richard Wood

Mechanical & Aerospace Engineering Faculty Publications

A wind tunnel test program was conducted at the Langley Full Scale Tunnel (LFST) to evaluate the performance of five passive drag reduction configurations on a modern straight truck at full scale. Configurations were tested in a build-up fashion with results representing a cumulative effect. Tested configurations include a front valance, a front box fairing, a boat-tail, an ideal side-skirt, and a practical side-skirt. Configurations were evaluated over a nominal 9 degree yaw sweep to establish wind averaged drag coefficients using SAE J1252. Genuine replicate yaw sweeps were used in an uncertainty analysis. Results show up to 28% improvement in …


Primary And Secondary Incident Management: Predicting Durations In Real Time, Asad J. Khattak, Xin Wang, Hongbing Zhang, Mecit Cetin Jan 2011

Primary And Secondary Incident Management: Predicting Durations In Real Time, Asad J. Khattak, Xin Wang, Hongbing Zhang, Mecit Cetin

Civil & Environmental Engineering Faculty Publications

Traffic incidents are a major source of congestion in Virginia. Secondary incidents comprise a relatively small but important portion of all incidents, and relatively little is known about their occurrence, characteristics, and associated delays. The main objectives of this study were to define secondary incidents, understand and analyze the occurrence and nature of such incidents, and develop tools that can comprehensively and continuously analyze primary and secondary incidents at the planning and operational levels, ultimately contributing to congestion management. The scope of the study is limited to freeway incidents in the Hampton Roads (HR) area. The study found that secondary …


Marine Buoy Detection Using Circular Hough Transform, Loc Tran, Justin Selfridge, Gene Hou, Jiang Li Jan 2011

Marine Buoy Detection Using Circular Hough Transform, Loc Tran, Justin Selfridge, Gene Hou, Jiang Li

Electrical & Computer Engineering Faculty Publications

A low cost method for buoy detection in maritime settings is presented using inexpensive digital cameras. In this method, the circular Hough transform is applied to an edge image to circular objects in the image. The center of these circles will signify the locations of each buoy. The known color information of the buoys is also used to enhance the performance by removing false detections. The algorithm is compared to an approach that locates buoys purely on color information. In order to validate the method, we test the approach synthetically and also with real images captured from a small surface …


Providing Location Security In Vehicular Ad Hoc Networks, Gongjun Yan Apr 2010

Providing Location Security In Vehicular Ad Hoc Networks, Gongjun Yan

Computer Science Theses & Dissertations

Location is fundamental information in Vehicular Ad-hoc Networks (VANETs). Almost all VANET applications rely on location information. Therefore it is of importance to ensure location information integrity, meaning that location information is original (from the generator), correct (not bogus or fabricated) and unmodified (value not changed). We present validation mechanisms to provide location integrity for VANETs. In the initial mechanism, we assume that all vehicles are equipped with a radar, a GPS receiver, and a transceiver. Since radar has a limited radar range and transceiver has a limited transmission range, we build network cells as a security unit as well …


Stability Analysis, Modeling, Simulation And Experimental Testing Of An Ems Maglev System With Structural Flexibility, Aravind M. Hanasoge Jul 2009

Stability Analysis, Modeling, Simulation And Experimental Testing Of An Ems Maglev System With Structural Flexibility, Aravind M. Hanasoge

Mechanical & Aerospace Engineering Theses & Dissertations

Vehicle-guideway interaction studies of Magnetically Levitated (Maglev) vehicles indicate that structural flexibility can adversely affect the overall stability and performance of such systems. This is one of the reasons why guideways are generally made very rigid. This in turn leads to increased cost of the overall system since guideway construction forms a significant portion of the overall cost. In this dissertation, the influence of structural flexibility on the stability of Electromagnetic Suspension (EMS) Maglev systems is studied. It is shown how inherently unstable and flexible structure EMS Maglev systems can achieve guaranteed stability by using collocated actuators and sensors, along …


Understanding Practical Limits To Heavy Truck Drag Reduction, Drew Landman, Richard Wood, Whitney Seay, John Bledsoe Jan 2009

Understanding Practical Limits To Heavy Truck Drag Reduction, Drew Landman, Richard Wood, Whitney Seay, John Bledsoe

Mechanical & Aerospace Engineering Faculty Publications

A heavy truck wind tunnel test program is currently underway at the Langley Full Scale Tunnel (LFST). Seven passive drag reducing device configurations have been evaluated on a heavy truck model with the objective of understanding the practical limits to drag reduction achievable on a modern tractor trailer through add-on devices. The configurations tested include side skirts of varying length, a full gap seal, and tapered rear panels. All configurations were evaluated over a nominal 15 degree yaw sweep to establish wind averaged drag coefficients over a broad speed range using SAE J1252. The tests were conducted by first quantifying …


A General Engineering Technology Program In Motorsports Technology, Gary Crossman, Anthony Dean Jun 2007

A General Engineering Technology Program In Motorsports Technology, Gary Crossman, Anthony Dean

Engineering Technology Faculty Publications

Southside Virginia, in particular the cities of Danville, Martinsville and the surrounding area, is the home of Virginia International Raceway and a rapidly growing motorsports industry. There is a strong need for educational opportunities to support manufacturing and related industries in this region. In the early 2000’s Patrick Henry Community College in Martinsville established an associate of applied science degree in Motorsports Technology to help meet the need for technical support personnel. As the industry has grown it has become evident that engineers and technologists are needed at the baccalaureate and masters levels. Old Dominion University (ODU), located in Norfolk, …


Computational Analysis And Validation Of The Hans Head And Neck Support, Kapil Tyagi Oct 2005

Computational Analysis And Validation Of The Hans Head And Neck Support, Kapil Tyagi

Mechanical & Aerospace Engineering Theses & Dissertations

One of the major causes of racing fatalities is basilar skull fracture from excessive head motions and neck loading in a frontal impact. There are many head/neck restraints available in the market but HANS head and neck support has proved to be the most efficient one in sled testing. This paper evaluates and compares the performance of the HANS device in MAthematical DYnamic MOdel (MADYMO) software with the sled testing. The tests were conducted for the frontal impact motions, with a crash pulse of 45 G's.

The goal of the tests was to evaluate the performance of HANS without the …


External Aerodynamics Of Heavy Ground Vehicles: Computations And Wind Tunnel Testing, Ilhan Bayraktar Apr 2002

External Aerodynamics Of Heavy Ground Vehicles: Computations And Wind Tunnel Testing, Ilhan Bayraktar

Mechanical & Aerospace Engineering Theses & Dissertations

Aerodynamic characteristics of a ground vehicle affect vehicle operation in many ways. Aerodynamic drag, lift and side forces have influence on fuel efficiency, vehicle top speed and acceleration performance. In addition, engine cooling, air conditioning, wind noise, visibility, stability and crosswind sensitivity are some other tasks for vehicle aerodynamics. All of these areas benefit from drag reduction and changing the lift force in favor of the operating conditions. This can be achieved by optimization of external body geometry and flow modification devices. Considering the latter, a thorough understanding of the airflow is a prerequisite.

The present study aims to simulate …


Computational Fluid Dynamic Study Of A Nascar Winston Cup Series Race Car, Terry L. Meek Jr. Oct 2001

Computational Fluid Dynamic Study Of A Nascar Winston Cup Series Race Car, Terry L. Meek Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

Since the goal of NASCAR racing is to win and since drag is a force the vehicle must overcome, a thorough understanding of the drag generating airflow around and through the automobile is greatly desired. The external airflow contributes to most of the drag that a car experiences and most of the downforce the vehicle produces. Therefore, an estimate of the vehicle's performance may be evaluated using a computational aerodynamics model. This thesis presents a computational fluid dynamic (CFD) analysis of a NASCAR Winston Cup series race car to investigate the salient flow characteristics.

Before a computational analysis could be …


Minimizing Post-Production Weight Growth In Tanks Using A Decision Analysis Model, Michael F. Cochrane Oct 1997

Minimizing Post-Production Weight Growth In Tanks Using A Decision Analysis Model, Michael F. Cochrane

Engineering Management & Systems Engineering Theses & Dissertations

Post-production weight growth of tanks is an historic problem for the military. Tanks are difficult to transport because of their weight, and post-production modifications tend to cause this weight to increase over the lifecycle of the tank. In this thesis, a computer model is constructed which uses influence diagrams to model tank weight growth as a probabilistic process. Historical weight data for the MI Abrams tank program is used to derive probabilities for the model. The model is used to predict tank weight growth over both the short and long term with the goal of understanding more about how and …


Application Of Reanalysis Techniques For Pattern Design Of Spot Welds, Young San Kim Jan 1996

Application Of Reanalysis Techniques For Pattern Design Of Spot Welds, Young San Kim

Mechanical & Aerospace Engineering Theses & Dissertations

Extensive benchmarking on competitive cars has shown that the durability of vehicles, assembly-induced variations, and assembly cost are directly related to the quality and number of spot welds. On most luxury cars, approximately 4,500 to 5,000 spot welds are found. On less expensive cars, the range is from 3,500 to 4,500. These cars usually inherit more noise, rattles, squeaks, and other quality-related problems. These problems have motivated the search for a new capability to systematically place welds in the most critical areas, with a minimum number of welds for car bodies, while satisfying all performance requirements (e.g., stiffness, stress distribution, …


Emissions Studies For A Natural Gas-Fired Internal Combustion Engine, Carlos M. Buitrago Oct 1993

Emissions Studies For A Natural Gas-Fired Internal Combustion Engine, Carlos M. Buitrago

Mechanical & Aerospace Engineering Theses & Dissertations

Since 1991, a University owned truck has been operating with natural gas. In order to improve emissions performance a different fuel management strategy was developed. With the help of Siemens Automotive in Newport News, VA, a liquid fuel injector was modified to handle natural gas. The basic engine was tested to determine the benefits in emissions that the multi-point injection system can have over the single point injection system that had been used previously. Pre-catalyst, raw exhaust-gas data for the more important pollutants were taken and analyzed in both systems under different loads and intake manifold pressures. In addition, to …


Large Capacity Missile Carrier (Cmx), C. N. Calvano, J. M. Berner, J. M. Bradley, K. A. Tosiello, D. T. Hooker, C. F. Merrill Jan 1993

Large Capacity Missile Carrier (Cmx), C. N. Calvano, J. M. Berner, J. M. Bradley, K. A. Tosiello, D. T. Hooker, C. F. Merrill

Engineering Management & Systems Engineering Faculty Publications

A systems engineering approach to the development of a radically different kind of surface combatant ship is presented, followed by a preliminary design of the ship shown by the analysis to be most effective. The requirement for the project was the development of a ship which would provide a major increase in the missile firepower of a battlegroup. The study conducts an analysis of four warfare scenarios and evaluates the effectiveness of replacing some Aegis ships with the missile carrier (CMX) and examines the relative utility of varying missile loads for the CMX. An alternative is chosen for further development …


Shape Sensitivity Analysis And Optimization Of Skeletal Structures And Geometrically Nonlinear Solids, Ching-Hung Chuang Apr 1992

Shape Sensitivity Analysis And Optimization Of Skeletal Structures And Geometrically Nonlinear Solids, Ching-Hung Chuang

Mechanical & Aerospace Engineering Theses & Dissertations

Formulations and computational schemes for shape design sensitivity analysis and optimization have been developed for both skeletal structures and geometrically nonlinear elastic solids. The continuum approach, which is based on the weak variational form of the governing differential equation and the concept of the material derivative, plays a central role in such a development.

In the first part of this work, the eigenvalue and eigenvector sensitivity equations for skeletal structures are derived with respect to configuration variables of joint and support locations. This derivation is done by the domain method as well as the boundary method. The discrete approach for …