Engineering Commons^™

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 …

Response Of A Warped Flexible Rotor With A Fluid Bearing, Jim Meagher, Xi Wu, Chris Lencioni

Mechanical Engineering

A two-complex-degrees-of-freedom model is developed and compared to experimental data for various amounts of rotor bow and its orientation to mass imbalance of the rotor. The equation of motion is developed by adding constant forces that rotate with the rotor to a Bently-Muszynska two-mode isotropic rotor model with a plane journal bearing. Diagnostic information discernable from probes at the bearing is explored and compared to midspan response, where previous research has concentrated. The model presented also extends earlier work by representing the effect of a nonrigid bearing. Good agreement between the analytical model and experiment demonstrates that the analysis presented …

The Viability Of Real-Time Prediction And Prevention Of Traffic Accidents, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

This paper addresses a novel idea of real-time traffic safety improvement on freeways. First by predicting traffic crashes on the freeway mainline using on-line loop detector data, then by proposing ITS remediation strategies to reduce the crash risk in real-time. The results of the predictive models were found to be consistent with the probable mechanisms of crashes under different flow regimes. Using micro-simulation software and the crash potential determined through the models developed in this research to associate traffic characteristics with the risk of a crash occurring, several mitigation strategies were attempted to improve safety in real-time. The before (pre-ITS) …

Assessing Safety On Dutch Freeways With Data From Infrastructure-Based Intelligent Transportation Systems, Mohamed Abdel-Aty, Anurag Pande, Abhishek Das, Willem Jan Knibbe

Civil and Environmental Engineering

Most freeway traffic surveillance technologies deployed around the world remain infrastructure based, with underground loop detectors being the most common among them. A proactive application for traffic surveillance data recently explored for some freeways in the United States is the estimation of real-time crash risk. The application involves establishing relationships between historical crashes and archived traffic data collected before those crashes. In these studies, crash occurrence on freeway sections has been related to temporal-spatial variation in speed and high lane occupancy. Critical modeling questions that remain unanswered relate to transferability of such an approach. This study attempts to address the …

Characteristics Of Urban Arterial Crashes Relative To Proximity To Intersections And Injury Severity, Abhishek Das, Anurag Pande, Mohamed Abdel-Aty, Joseph B. Santos

Civil and Environmental Engineering

Intersections of an urban arterial corridor may influence crashes that occur even beyond their physical area. This study examines the effect of the gradual change in the distance of intersection influence on crash characteristics that explain injury severity outcomes of arterial crashes. The approach adopted involves simultaneous estimation of two variables: an ordinal variable representing crash-injury severity and a binary variable representing crash location (intersection versus segment crashes). The dichotomy in crash location is based on the threshold distance of intersection influence. Five sets of bivariate simultaneous models were estimated by using five threshold distances of influence varying from 0 …

Discovering Indirect Associations In Crash Data Through Probe Attributes, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Association analysis is a popular data-mining technique for detecting dependencies in transaction databases. The algorithms for discovery of association rules attempt to find the products that tend to sell together. For this purpose, one can treat crashes as individual transactions and crash characteristics as the "products" part of that transaction to discover patterns of the crash characteristics that tend to coexist. The a priori algorithm to search for association rules employs the lower bound on intersection (i.e., joint) frequency of two crash characteristics to ensure that only significant patterns are discovered. Hence, remarkable associations relating crash characteristics that have joint …

Understanding The Impact Of A Recent Hurricane On Mobilization Time During A Subsequent Hurricane, Vinayak V. Dixit, Anurag Pande, Essam Radwan, Mohamed Abdel-Aty

Civil and Environmental Engineering

It is not uncommon for a region to be affected by multiple hurricanes in a span of a few weeks. The behavior of the evacuees during a subsequent hurricane in the same season is affected by the damage to the infrastructure and to the vehicles and assets belonging to evacuees, as well as by the psychological impact of the preceding hurricane. One such behavioral aspect that affects traffic-loading rates during a hurricane is the evacuation delay or mobilization time. In this study, "mobilization time for an evacuee" is defined as the difference between the time at which the decision to …

Simulated Effects Of Dynamic Row Spacing On Energy And Water Conservation In Semi-Arid Central California Greenhouses, A. Moya, T. Mehlitz, Ilhami Yildiz, S. F. Kelly, C. Hardin

BioResource and Agricultural Engineering

Considerable effort is expended to conserve energy and water in current greenhouse systems, and look for alternative energy sources, especially passive heating and cooling strategies. Proper environmental management systems can significantly change the energy and moisture dynamics of greenhouse production systems. In this study, specifically, influences of dynamic row spacing on energy and water conservation were investigated. A dynamic computer simulation model was used to compare different row spacings, plant heights, and leaf dimensions to draw a conclusion about energy and water conservation. The results showed that using smaller spacings between cucumber crop rows (for instance, 0.5 m instead of …

Simulated Performance Of A Renewable Energy Technology – Heat Pump Systems In Semi-Arid California Greenhouses, C. Hardin, T. Mehlitz, Ilhami Yildiz, S. F. Kelly

BioResource and Agricultural Engineering

In addition to the labor, energy and water consumption are the two main cost drivers in current greenhouse systems. Consequently, considerable effort is expended to conserve energy and water, and look for alternative energy sources, especially environmentally friendly renewable energy sources and technologies. Greenhouses in hot and arid regions also require large quantities of water for irrigation. Using proper technologies and environmental management systems can significantly change the energy and moisture dynamics of greenhouse production systems. This study aims to focus on reducing natural gas, electricity, and water consumption in semi-arid California greenhouses introducing renewable energy heat pump technologies to …

Simulated Effects Of Reflective Mulch On Energy And Water Conservation In Semi-Arid Central California Greenhouses, T. Mehlitz, Ilhami Yildiz, S. Rahman, C. Hardin

BioResource and Agricultural Engineering

In addition to the labor, energy and water consumption are the two main cost drivers in current greenhouse systems. Consequently, considerable effort is expended to conserve energy and water, and look for alternative energy sources. Greenhouses in hot and arid regions also require large quantities of water for irrigation. Proper environmental management systems can significantly change the energy and moisture dynamics of greenhouse production systems. This study aims to focus on reducing energy and water consumption in semi-arid California greenhouses. Influences of mulch (having different reflectivities) on energy and water conservation were investigated. The reflectivity of mulch used as a …

Design And Evaluation Of A Greenhouse Interface For Climate Control Programming And Networking, G. Diaz, S. F. Kelly, Ilhami Yildiz

BioResource and Agricultural Engineering

At Cal Poly the motto is “Learn by Doing”. In the College of Agriculture, this is especially true and many of the labs provide an opportunity for students to implement this philosophy. Updated climate controls were installed in a series of greenhouses on the top floor of the Agricultural Science building that are used for student and faculty research projects. A Programmable Logic Controller (PLC) was installed to actuate the various vents, shading, heating, cooling and irrigation. A control program was developed to control and log temperatures and other operating parameters to monitor the greenhouse. An easy to use computer …

Simulated Effects Of Various Environmental Management Practices On Energy Consumption In Open And Confined Greenhouse Systems, Ilhami Yildiz, D. P. Stombaugh

BioResource and Agricultural Engineering

The objective of this study was to evaluate the effects of relative humidity, light management levels, minimum ventilation rates, CO₂ enrichment and canopy size on energy consumption in three different greenhouse systems (conventional, open-loop heat pump, and confined heat pump) in winter, spring, and summer months. No difference was observed in energy consumption with relative humidity set point levels in winter due to the already low relative humidity levels. Some differences were observed in spring and summer due to extra dehumidification required to maintain the inside relative humidity at lower levels. Energy consumption in summer was reduced up to …

Simulated Effects Of Various Environmental Management Practices On Water Consumption In Open And Confined Greenhouse Systems, Ilhami Yildiz, D. P. Stombaugh

BioResource and Agricultural Engineering

The objective of this study was to evaluate the effects of relative humidity, light management, minimum ventilation rates, CO₂ enrichment and canopy size on water consumption in three different greenhouse systems (conventional, open heat pump, and confined heat pump) in winter, spring, and summer months. Using different relative humidity set points resulted in almost the same relative humidity regimes within the confined greenhouse system, resulting in similar transpiration rates. No difference was observed in transpiration rates in the open system in winter either, because the inside relative humidity levels never reached the 70% and 80% set points. Some differences …

Irrigation District Energy Survey, Charles M. Burt, Daniel J. Howes

BioResource and Agricultural Engineering

This survey was completed by ITRC on behalf of the California Energy Commission Public Interest Energy Research (PIER) Program. The purpose of the survey was to establish a benchmark for the present status of the pumping systems used by agricultural water districts in California and to determine the districts' needs. The needs discussed involve technical assistance, research grant and low-interest loan funding, and district-related policy issues. Thirty agricultural water districts were selected for the survey. These districts were selected based on energy use per acre of irrigated area, size, geographic location, and distribution infrastructure.