Engineering Commons^™

New Orleans And Hurricane Katrina. Iii: The 17th Street Drainage Canal, R. B. Seed, R. G. Bea, A. Athanasopoulos-Zekkos, G. P. Boutwell, J. D. Bray, C. Cheung, D. Cobos-Roa, L. F. Harder, Jr., Robb E.S. Moss, J. M. Pestana, M. F. Riemer, J. D. Rogers, R. Storesund, X. Vera-Grunauer, J. Wartman

Civil and Environmental Engineering

The failure of the levee and floodwall section on the east bank of the 17th Street drainage canal was one of the most catastrophic breaches that occurred during Hurricane Katrina. It produced a breach that rapidly scoured a flow pathway below sea level, so that after the storm surge had largely subsided, floodwaters still continued to stream in through this breach for the next two and a half days. This particular failure contributed massively to the overall flooding of the Metropolitan Orleans East Bank protected basin. Slightly more than half of the loss of life, and a similar fraction of …

Freeway Work-Zone Crash Analysis And Risk Identification Using Multiple And Conditional Logistic Regression, Rami Harb, Essam Radwan, Xuedong Yan, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Work-zone safety continues to be a priority and a concern for the Federal Highway Association as well as most state departments of transportation. The main objective of this study is to uncover work-zone freeway crash characteristics to help develop countermeasures that limit work-zones’ hazards. The Florida Crash Records Database for years 2002, 2003, and 2004 was utilized for this study. Conditional logistic regression along with stratified sampling and multiple logistic regression models were estimated to unveil work-zone freeway crash traits. According to the models’ results, roadway geometry, weather condition, age, gender, lighting condition, residence code, and driving under the influence …

Exploration Of Crash Prone Traffic Conditions On Freeways In The Netherlands Using Random Forests, Mohamed Abdel-Aty, Anurag Pande, Abhishek Das, Wiilem Jan Knibbe

Civil and Environmental Engineering

Underground loop detectors are one of the most common traffic surveillance apparatus on freeways. Traffic data obtained from these detectors are used for various ITS (Intelligent Transportation Systems) applications such as travel time estimation and incident detection. In the recent past, however, researchers have been interested in proactive applications of these data. These proactive applications primarily involve real-time crash risk assessment based on analysis of traffic surveillance data observed prior to historical crashes. In this study, we have analyzed the crash data from five freeway sections in the Utrecht region of the Netherlands to identify the traffic conditions significantly associated …

Evaluating Route Diversion As A Strategy For Reduction Of Real-Time Crash Risk On Freeways Using Microscopic Simulation, Vikash V. Gayah, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

The objective of this study is to evaluate route diversion as a strategy for reducing crash risk on freeways using Microsimulation. Traffic simulation environment provides the 'loop detector data' which in turn are the inputs to the models used for real-time crash risk estimation. It has been found that rear-end crashes are more accurately described as occurring within one of two distinct traffic regimes. Hence, the crash risk estimates for rear-end crashes belonging to Regime 1 and Regime 2 are output posterior probabilities from two different models which are not directly comparable. A method was proposed to transform the output …

Power Quality Measurements Of A Dc Motor Drive, Nikil Mulakken, Taufik, Makbul Anwari

Electrical Engineering

This paper presents the results of power quality measurements performed on a DC motor drive. The power quality measurements involve a laboratory setup to investigate how various loading conditions on DC drive affect the efficiency, input power factor and total harmonic distortion of output armature current of a DC drive. Through the capture of this information, ways to minimize losses associated with the DC motor drive could be achieved based on finding an optimal operating point or region.

Effects Of Transverse Mode Coupling And Optical Confinement Factor On Gallium-Nitride Based Laser Diode, Xiaomin Jin, Zhang Bei, Dai Tao, Zhang Guo-Yi

Electrical Engineering

We have investigated the transverse mode pattern and the optical field confinement factor of gallium nitride(GaN) laser diodes (LDs) theoretically. For the particular LD structure, composed of approximate 4 μm thick n-GaN substrate layer, the maximum optical confinement factor was found to be corresponding to the 5th order transverse mode, the so-called lasing mode. Moreover, the value of the maximum confinement factor varies periodically when increasing the n-sideGaN layer thickness, which simultaneously changes and increases the oscillation mode order of the GaN LD caused by the effects of mode coupling. The effects of the thickness and the average composition of …

Electric Motor Efficiency Under Variable Frequencies And Loads, Charles M. Burt, Xianshu Piao, Franklin Gaudi, Bryan Busch, Taufik

Electrical Engineering

This paper details a study performed by the Irrigation Training and Research Center to determine motor performances under varying speeds [induced by a variable frequency drives (VFD) controller]and loads. A further goal of the study was to provide sufficient information to designers so that they could estimate total pumping plant power usage with a VFD-controlled installation. Motors were tested with a VFD as well as across-the-line. On average, the relative efficiency of the electrical system with a VFD may be approximately 8% lower than the relative efficiency of a properly designed, full-load across-the-line system. If one considers actual field operating …

Real-Time Telemetry Options For Ocean Observing Systems, Bridget Benson, G. Chang, F. Spada, D. Manov, R. Kastner

Electrical Engineering

Ocean observing systems provide a means to monitor oceanic variables on a variety of temporal and spatial scales. Data from ocean observing systems are most useful when they are collected in real-time; real-time data allow the detection of important events as they occur. Various real-time telemetry options exist for transferring data from sea to shore and from the subsurface to the surface. We survey these telemetry options to highlight the research problems associated with subsea to surface to shore networking and include a comparison of existing real-time technologies for three specific ocean observing system network topologies with respect to data …

Characterization Of Thermally Evaporated Ag-Ge-S Thin Films, Fei Wang, William Porter Dunn, Mukul Jain, Carter De Leo, Nicholas Vicker, Richard Savage, Xiaomin Jin, Sergey Mamedov, Punit Boolchand

Electrical Engineering

Thin films of ternary (GeS₃)_1-xAg_x glasses (x=0.1 and 0.2) are studied in this work. Thin films are fabricated in a vacuum thermal evaporator at 3 different evaporation angles (0^o, 30^o and 45^o). All thin film samples are examined in Raman spectroscopy. Raman results of both normally and obliquely deposited thin film samples reveal Ge-S CS modes (~340cm^-1) , Ge-S ES (~360cm^-1) modes, and thiogermanate modes Q₁~Q₃ (390cm^-1~437cm^-1). In addition, sharp peaks due to sulfur rings (S₈) are …

Mobile Free Space Optical Communication System, Xian Wang, Chi Yeh Hsu, Xiaomin Jin

Electrical Engineering

The paper discusses a low power consumption, light weight and low cost 10MHz free-space optical communication (FSO). The system is designed for mounting on mobile platforms, with effective range of at least 50 meters. Light-Emitting Diodes (LEDs) and Laser diodes (LDs) are used in the transmitter for comparison for their relative performance in the system. The receiver features a beam splitter that feeds part of the data link optical signal to a quadrant photodetector and controls a tracking/stabilization system using microcontroller. Since almost all commercial FSO systems are mounted on fixed positions such as buildings, the paper explores the possibility …

Analytical And Numerical Methodology For Modeling Temperatures In Landfills, James L. Hanson, Wei-Lien Liu, Nazli Yesiller

Civil and Environmental Engineering

Analytical and numerical approaches have been developed for modeling temperatures in municipal solid waste landfills. Steps for model formulation and details of boundary conditions are described. The formulation was based on a transient conductive heat transfer analysis. Conventional earth temperature theories were modified for landfill systems by incorporating heat generation functions representing biological decomposition of wastes. Finite element analysis was used for general modeling and parametric evaluations. Thermal properties of materials were determined using field observations and data reported in literature. The boundary conditions consisted of seasonal temperature cycles at the ground surface (established using near-surface field measurements) and constant …

Engineering Controlled Low Strength Materials Using Scrap Tire Rubber, Tammie Cheung, Daniel C. Jansen, James L. Hanson

Civil and Environmental Engineering

An investigation was conducted to determine the influence of recycled scrap tire rubber on the engineering properties of controlled low strength material (CLSM). With control over the ultimate compressive strength of CLSMs being key for applications such as backfilling utility trenches where re-excavation is often necessary, incorporation of scrap tire rubber into the CLSM mixture is a viable way to limit the ultimate strength. The work presented includes the results of 27 batches of CLSM, 20 of which included scrap tire rubber. The variables included: cement content, fly ash content, and fractional replacement of sand with scrap tire rubber. Results …

Effect Of Unitization And Product Types On Readability Of Tagged Packages Of Consumer Goods, Jay A. Singh, R. Holtz, S. P. Singh, K. Saha

Industrial Technology and Packaging

Proper implementation of radio frequency identification (RFID) has the potential to revolutionize supply chain management. This technology provides simultaneous indirect scanning of multiple packages and palletized loads equipped with a RFID tag, transmitting substantially more information than a bar code. Also, stored information on the tag can be updated according to inventory status, thus, eliminating key limitations of barcode technology. This study was designed to address some of the currently known shortcomings of the RFID technology. One of the commonly occurring drawbacks is transmitted signal from RFID antennae is reflected from metal objects or absorbed by water contained in a …

Rfid Research And Testing For Packages Of Apparel, Consumer Goods And Fresh Produce In The Retail Distribution Environment, S. P. Singh, M. Mccartney, Jay Singh, R. Clarke

Industrial Technology and Packaging

Radio frequency identification (RFID) is a term used for any device that can be sensed at a distance by radio frequencies with few problems of obstruction. The origins of the term lie in the invention of tags that reflect or retransmit a radiofrequency signal. According to a recent article by Forrester Research, the minimal ‘Slap and Ship’ approach to RFID compliance will cost an individual company between $2 million and $20 million. Because retailers like Wal-Mart plan to share with their suppliers all the RFID-generated data points (from when a case/pallet enters their distribution centre until it leaves their stockroom), …

Experience Learned: Incorporating Industry Supported Project In Power Electronics Course To Improve Learning, Taufik

Electrical Engineering

One approach to enhance students’ learning in practical engineering design issues is to expose students to real world projects using real world components. In introductory power electronics course at Cal Poly, this approach has been implemented through industry’s involvement in the final hardware design project. This paper describes experience learned from incorporating this industry sponsored hardware design project. Results to assess this approach through survey conducted by students will be presented.

Now Hear This! What All Environmental Engineers Should Know About Noise Control, Harold M. Cota, Mark Bastasch, Roger Wayson, Tracy Thatcher

Civil and Environmental Engineering

Noise is an is an that affects almost everyone. And even though environmental engineers are often called on to deal with noise-related problems, most of them receive little or no academic training in noise control. This primer suggests why all environmental engineers should know something about noise control, what they need to know, and where they can find the necessary information.

Electric Motor Efficiency Under Variable Frequencies And Loads, Charles M. Burt, Xianshu Piao, Franklin Gaudi, Bryan Busch, N. F. N. Taufik

BioResource and Agricultural Engineering

This paper details a study performed by the Irrigation Training and Research Center to determine motor performances under varying speeds [induced by a variable frequency drives (VFD) controller] and loads. A further goal of the study was to provide sufficient information to designers so that they could estimate total pumping plant power usage with a VFD-controlled installation. Motors were tested with a VFD as well as across-the-line. On average, the relative efficiency of the electrical system with a VFD may be approximately 8% lower than the relative efficiency of a properly designed, full-load across-the-line system. If one considers actual field …

Sgdbr Single-Chip Wavelength Tunable Lasers For Swept Source Oct, Dennis J. Derickson, Mike Bernacil, Andrew Dekelaita, Ben Maher, Shane O'Connor, Mathew N. Sysak, Leif Johanssen

Electrical Engineering

Sampled Grating Distributed Bragg Reflector (SGDBR) monolithic tunable lasers are now entering the production phase in telecommunications applications. These tunable lasers are unique in that they offer wide wavelength tuning (1525 to 1565 nm), fast wavelength tuning (5 ns) and high speed amplitude modulation all on the same monolithic chip1,2,3,4. This work studies the applicability of SGDBR monolithic tunable laser diodes for biomedical imaging using swept-wavelength or Fourier domain optical coherence tomography. This paper will present our work involved with utilizing the strengths (table 1) of this SGDBR laser class and mitigating the weaknesses (table 2) of this device for …

Nonlinear Contact Analysis Of Gear Teeth For Malfunction Diagnostics, D. Kong, J. M. Meagher, C. Xu, X. Wu, Y. Wu

Mechanical Engineering

Gearboxes sustain a variety of faults such as broken-shafts, eroded, broken, or missing teeth, and even broken-cases. Casing mounted accelerometers can detect fault patterns but the signals are complicated and difficult to interpret. This study considers the tooth loading of ideal gears and gears with defects. A large industrial gearbox used in a 12m³ electric mining shovel is modeled. The nonlinear contact mechanics is analyzed to predict the bearing supporting force variation vs. the gear tooth loading after a 3-D CAD model of the gearbox is transferred into multi-body dynamics software. The contact mechanics model of the meshing teeth …

A Spy Under The Hood: Controlling Risk And Automotive Edr, Peter R. Thom, C. Arthur Maccarley

Electrical Engineering

No abstract provided.

Detached-Eddy Simulation Of The Vortical Flowfield About The Vfe-2 Deltawing, Russell M. Cummings, Andreas Schϋtte

Aerospace Engineering

The numerical simulation of the flow around a 65° delta wing configuration with rounded leading edges is presented. For the numerical simulation the Cobalt Code uses a cell-centered unstructured hybrid mesh approach. Several numerical results are presented for the steady RANS equations as well as for DES and DDES hybrid approaches. The simulations are done as part of the NATO RTO/AVT 113 working group focusing on experimental and numerical research on delta wing configurations with rounded leading edges. Within this paper the focus is related to the dual primary vortex flow topology, especially the sensitivity of the flow to angle …

Introduction Of Software Development Practices Into Aerospace Engineering Curriculum, David D. Marshall, Eric A. Mehiel

Aerospace Engineering

This paper will discuss the attempts to incorporate software development practices into the aerospace engineering curriculum in order to improve the computer programming capabilities of the students. The main focus is on techniques to integrate functional decomposition, unit level testing, system integration and testing, and verification and validation processes without significantly increasing the workload on the students. The approach taken is an integrated approach where the required information needed for testing and validation are integrated into the course content via in-class examples and homework problems. This same approach was taken for the other software development skills. This has been integrated …

Aerodynamic Performance Enhancement Of A Naca 66-206 Airfoil Using Supersonic Channel Airfoil Design, David Giles, David D. Marshall

Aerospace Engineering

Supersonic channel airfoil design techniques have been shown to significantly reduce drag in high-speed flows over diamond shaped airfoils by Ruffin and colleagues. The effect of applying these techniques to a NACA 66-206 airfoil is presented. The design domain entails channel heights of 8-16.6% thickness-to-chord and speeds from Mach 1.5-3.0. Numerical simulations show an increase in the lift-to-drag ratio for airfoils at Mach 2.5 at a 35,000-ft altitude with a 12% channel height geometry showing a benefit of 17.2% at 6-deg angle of attack and a sharp channel leading edge. Wave drag is significantly reduced while viscous forces are slightly …

Short Takeoff Performance Using Circulation Control, Tyler Ball, Scott Turner, David D. Marshall

Aerospace Engineering

Historically, powered lift takeoff analysis has been prohibitively expensive for use in preliminary design. For powered lift, the coupling of aircraft systems invalidates traditional simplistic methods often used in early aircraft sizing. This research creates a tool that will automate the process of takeoff and balanced field length calculations for a circulation control wing aircraft. The process will use high fidelity techniques, such as computational fluid dynamics in order to capture the coupled effects present in circulation control along with Gaussian processes to create a metamodel of that same data to be implemented in a modular takeoff/BFL model. The model …

Performance Comparison Of Thermal Insulated Packaging Boxes, Bags And Refrigerants For Single-Parcel Shipments, S. P. Singh, Gary J. Burgess, Jay Singh

Industrial Technology and Packaging

A range of packaging solutions exists for products that must be kept within a specific temperature range throughout the supply-and-distribution chain. This report summarizes the results of studies conducted over a span of 2 years by the Consortium for Distribution Packaging at Michigan State University. Thermal insulation packaging materials such as expanded polystyrene, polyurethane, corrugated fibreboard, ThermalCor® and other composite packaging such as thermal insulating bags were studied. Phase change materials such as gel packs were also evaluated. Properties such as R-value, melting point and heat absorption were examined and are reported.

Power Amplifier Principles And Modern Design Techniques, Vladimir I. Prodanov, Mihai Banu

Electrical Engineering

No abstract provided.

Super Barrier Rectifier—A New Generation Of Power Diode, Vladimir Rodov, Alexei L. Ankoudinov, Taufik

Electrical Engineering

The main principle behind the new super barrier rectifier (SBR) approach is to create the “super” barrier for majority carriers without unreliable metal–semiconductor Schottky contact. The SBR technology creates such barrier in the MOS channel. The height of this barrier can be easily adjusted by the doping concentration in the channel. This paper demonstrates that the new power diodes combine high performance and high reliability for low voltage applications (below 100 V). The underlying concepts and analysis of operation are presented as well as the laboratory test results that compare performance and reliability between Schottky and the new SBR diode.

Cartilage Growth And Remodeling: Modulation Of Balance Between Proteoglycan And Collagen Network In Vitro With Β-Aminopropionitrile, Anna Asanbaeva, Koichi Masuda, Eugene J-M.A. Thonar, Stephen M. Klisch, Robert L. Sah

Mechanical Engineering

Objective

To examine the effect of β-aminopropionitrile (BAPN), an inhibitor of lysyl oxidase, on growth and remodeling of immature articular cartilage in vitro.

Design

Immature bovine articular cartilage explants from the superficial and middle layers were cultured for 13 days in serum-containing medium with or without BAPN. Variations in tissue size, accumulation of proteoglycan and collagen (COL), and tensile mechanical properties were assessed.

Results

The inclusion of serum resulted in expansive tissue growth, stimulation of proteoglycan and COL deposition, and a diminution of tensile integrity. Supplementation of medium with BAPN accentuated this phenotype in terms of a further increase in …

Cal Poly Wind Power Research Center, Patrick Lemieux, John Ridgely

Mechanical Engineering

The Wind Power Research Center is being created at California State Polytechnic University in San Luis Obispo, California. This center brings together faculty, undergraduate and graduate students, and industry partners to conduct applied research and education in support of the wind power industry. Particular emphasis is given to research which serves the needs of manufacturers of smaller wind turbines, and to educating engineers who are well trained to work in all segments of the wind power industry.

A Two-Disk Extended Jeffcott Rotor Model Distinguishing A Shaft Crack From Other Rotating Asymmetries, Xi Wu, Jim Meagher

Mechanical Engineering

A mathematical model of a cracked rotor and an asymmetric rotor with two disks representing a turbine and a generator is utilized to study the vibrations due to imbalance and side load. Nonlinearities typically related with a “breathing” crack are included using a Mayes steering function. Numerical simulations demonstrate how the variations of rotor parameters affect the vibration response and the effect of coupling between torsional and lateral modes. Bode, spectrum, and orbit plots are used to show the differences between the vibration signatures associated with cracked shafts versus asymmetric shafts. Results show how nonlinear lateral-torsional coupling shifts the resonance …