Engineering Commons^™

The Four-Domain Development Diagram: A Tool For Designing Development-Centered Teaching, Linda Vanasupa, Trevor S. Harding, William L. Hughes

Materials Engineering

Research in education has brought to light the complexity of the learning process, demonstrating that students' development is influenced by a myriad of cultural and social factors, as well as the environment in which learning takes place. Engineering curricula, however, are primarily focused on teaching content knowledge, often resulting in a gap between what is taught and what is learned. We propose that shifting some of the focus onto the process of learning that occurs within the student and leveraging multiple known connections from educational psychology can result in more effective engineering education. Here we define “effective” engineering education as …

Nicotinic Acetylcholine Receptor Kinetics Of The Neuromuscular Junction Simulated Using Spice: An Illustration Of Physiological Process Simulation With Conventional Circuit Simulation Software, Robert B. Szlavik

Biomedical Engineering

With the advent of modern day computational power, there is a great deal of interest in the simulation and modeling of complex biological systems. A significant effort is being made to develop generalized software packages for the simulation of cellular processes, metabolic pathways and complex biochemical reaction systems. The advantages to being able to implement and simulate complex biological systems in a virtual environment are several. Simulations of this type, if sufficiently detailed, provide experimental physiologists with the ability to visualize the dynamics of a given biological system of interest. The validity of hypotheses related to the system under study …

Action At Distance: A Ms Degree Offered Through Distance Learning As A Vector To Student Enrichment And Industrial Interaction, Lanny Griffin, Daniel Walsh, Robert Crockett, Robert B. Szlavik

Biomedical Engineering

This paper describes the development and implementation of a flourishing MS program offered through distance learning (DL). The program serves the mission of the university – polytechnic education. It provides an intense life-long-learning opportunity for some of the 300,000 degreed engineers working in California industry who can benefit from graduate education. The DL Masters Degree Program in Engineering with a Biomedical Specialization was designed and developed with verisimilitude to the on-campus program in mind. The distance students attend the same classes as students on campus. The DL program has the same learning objectives and student outcomes as those expected for …

An Automatic Alogorithm For Detecting Stent Endothelialization From Volumetric Optical Coherence Tomography Datasets, Garret T. Bonnema, Kristen O'Halloran Cardinal, Stuart K. Williams, Jennifer K. Barton

Biomedical Engineering

Recent research has suggested that endothelialization of vascular stents is crucial to reducing the risk of late stent thrombosis. With a resolution of approximately 10 μm, optical coherence tomography (OCT) may be an appropriate imaging modality for visualizing the vascular response to a stent and measuring the percentage of struts covered with an anti-thrombogenic cellular lining. We developed an image analysis program to locate covered and uncovered stent struts in OCT images of tissue-engineered blood vessels. The struts were found by exploiting the highly reflective and shadowing characteristics of the metallic stent material. Coverage was evaluated by comparing the luminal …

Microwave Signal Generation Using Self-Heterodyning Of A Fast Wavelength Switching Sg-Dbr Laser, Michael A. Bernacil, Shame O' Connor, Ben Maher, Andew Dekelaita, Dennis J. Derickson

Electrical Engineering

Microwave signal generation using self-heterodyning of a single wavelength tunable SG-DBR laser is demonstrated. Microwave signals are established by quickly hopping back and forth between two optical wavelengths. These wavelengths are made time coincident through a delay line interferometer. The output of the interferometer is photodetected resulting in a CW microwave signal. This method does not require conventional master-slave laser configurations, external microwave drive sources, or a mode locked laser used to beat dual longitudinal modes. Microwave signals up to 12 GHz have been measured by frequency modulating the phase section of the SG-DBR laser with low frequency RF square …

An Fpga Design Space Exploration Tool For Matrix Inversion Architectures, A. Irturk, B. Benson, S. Mirzaei, R. Kastner

Electrical Engineering

Matrix inversion is a common function found in many algorithms used in wireless communication systems. As FPGAs become an increasingly attractive platform for wireless communication, it is important to understand the tradeoffs in designing a matrix inversion core on an FPGA. This paper describes a matrix inversion core generator tool, GUSTO, that we developed to ease the design space exploration across different matrix inversion architectures. GUSTO is the first tool of its kind to provide automatic generation of a variety of general purpose matrix inversion architectures with different parameterization options. GUSTO also provides an optimized application specific architecture with an …

A Cartilage Growth Mixture Model With Collagen Remodeling: Validation Protocols, Stephen M. Klisch, Anna Asanbaeva, Sevan R. Oungoulian, Koichi Masuda, Eugene J.-Ma. Thonar, Andrew Davol, Robert L. Sah

Mechanical Engineering

A cartilage growth mixture (CGM) model is proposed to address limitations of a model used in a previous study. New stress constitutive equations for the solid matrix are derived and collagen (COL) remodeling is incorporated into the CGM model by allowing the intrinsic COL material constants to evolve during growth. An analytical validation protocol based on experimental data from a recent in vitro growth study is developed. Available data included measurements of tissue volume, biochemical composition, and tensile modulus for bovine calf articular cartilage (AC) explants harvested at three depths and incubated for 13 days in 20% fetal borine serum …

Development Of A Laboratory Based Sustainability Course For Environmental Engineers, Samuel A. Vigil

Civil and Environmental Engineering

An understanding of sustainability is important for all engineering students, but especially for Environmental Engineers who will be taking leadership roles on sustainability issues. This paper will discuss the development of a graduate and senior level course which provides the knowledge, computational, and experimental skills in sustainability for these future engineering leaders. The course includes both lecture and laboratory sections.

Techniques For Developing Large Scale Fuzzy Logic Systems, Jon C. Ervin, Sema E. Alptekin

Industrial and Manufacturing Engineering

In this paper, we describe various techniques used to make Intuitionistic Fuzzy Logic Systems amenable to operating on applications with large numbers of inputs. A rule reduction technique known as Combs method is combined with an automated tuning process based on Particle Swarm Optimization. A second stage of tuning on rule weights results in improved performance and further reduction in the size of the rule-base. The entire process has been developed to operate within the Matlab software environment. The technique is tested against the Wisconsin Breast Cancer Database. The use of these tools shows great promise in significantly expanding the …

Accuracy Of Global Microirrigation Distribution Uniformity Estimates, Stuart W. Styles, Charles M. Burt, Franklin Gaudi, Sierra Layous

BioResource and Agricultural Engineering

Emitter pressures and flow rates were systematically and extensively sampled in one drip and one microspray field. The data distributions are presented. The accuracy of rapid (limited samples) evaluation pressure sampling procedures was found to be quite good if the pressure distribution was systematic, but erroneous if the pressure distribution throughout a field was random. A simple mathematical combination of two nonuniformity components (due to pressure differences, and other causes of flow variation) provided a better estimate of overall system distribution uniformity than more complex mathematics.

A New Pruning Algorithm For Neural Network Dimension Analysis, Devin Sabo, Xiao-Hua Yu

Electrical Engineering

The choice of network dimension is a fundamental issue in neural network applications. An optimal neural network topology not only reduces the computational complexity, but also improves its generalization capacity. In this research, a new pruning algorithm based on cross validation and sensitivity analysis is developed and compared with three existing pruning algorithms on various pattern classification problems. Computer simulation results show the network size can be significantly reduced using this new algorithm while the neural network still maintains satisfactory generalization accuracy.

Gaussian Process Metamodeling Applied To A Circulation Control Wing, Scott Turner, Tyler Ball, David D. Marshall

Aerospace Engineering

Metamodeling fluid systems is an efficient way to do complex analysis on multivariate problems and can allow for time savings in an optimization setting. Gaussian process metamodels provide a flexibility in modeling that can be extended to both experimental and deterministic experiments. This paper specifically addresses such models applied to computational fluid dynamics analysis of a D circulation control wing. The framework for a generalized approach is first overviewed and then applied to the analysis of the aerodnamics. The Gaussian process regression was essential for both simplifying the calculations required for balanced field length computation and for analysis of complex …

Conversion To Groundwater Pumping With Drip/Micro Irrigation Systems, Charles M. Burt, Monte Soto

BioResource and Agricultural Engineering

Twenty one irrigation districts in the Central Valley reported “conversion acres”. Conversion acres are those on which farmers used only groundwater for drip/micro irrigation although surface irrigation water was available.

The twenty one districts include about 2 million acres of irrigated area. Approximately 3.6% of that acreage (73,000 acres) has been “converted” to groundwater when farmers switched to drip/micro. Fourteen of these districts anticipate more conversion in the future. ITRC thinks that the conversion will be more rapid and greater than district personnel suspect.

The dominant factor that influences the conversion was the lack of flexible water delivery service to …

Two-Dimensional Computer-Generated Ornamentation Using A User-Driven Global Planning Strategy, Dustin Robert Anderson

Master's Theses

Hand drawn ornamentation, such as floral or geometric patterns, is a tedious and time consuming task that requires much skill and training in ornamental design principles and aesthetics. Ornamental drawings both historically and presently play critical roles in all things from art to architecture; however, little work has been done in exploring their algorithmic and interactive generation. The field of computer graphics offers many algorithmic possibilities for assisting an artist in creating two-dimensional ornamental art. When computers handle the repetition and overall structure of ornament, considerable savings in time and money can result. Today, the few existing computer algorithms used …

A Case-Study Based Course On "Device Evaluation And Fda Approval", Kristen O'Halloran Cardinal

Biomedical Engineering

Preclinical evaluation of new devices and therapies is an integral part of research and development in the medical device industry, and the regulatory process for FDA approval is a major driving force behind much that goes on in a company setting. A large number of graduating biomedical engineers enter this medical device industry or a related environment upon graduation from our institution. Although these engineers are equipped to address many of the technical challenges that will arise, there is currently limited formal training in or exposure to the regulatory process that is required to bring new devices to market. Knowledge …

Articular Cartilage Tensile Integrity: Modulation By Matrix Depletion Is Maturation-Dependent, Anna Asanbaeva, Johnny Tam, Barbara L. Schumacher, Stephen M. Klisch, Koichi Masuda, Robert L. Sah

Mechanical Engineering

Articular cartilage function depends on the molecular composition and structure of its extracellular matrix (ECM). The collagen network (CN) provides cartilage with tensile integrity, but must also remodel during growth. Such remodeling may depend on matrix molecules interacting with the CN to modulate the tensile behavior of cartilage. The objective of this study was to determine the effects of increasingly selective matrix depletion on tensile properties of immature and mature articular cartilage, and thereby establish a framework for identifying molecules involved in CN remodeling. Depletion of immature cartilage with guanidine, chondroitinase ABC, chondroitinase AC, and Streptomyces hyaluronidase markedly increased tensile …

The Effect Of Ventilation And Hand Holes On Loss Of Compression Strength In Corrugated Boxes, Jay Singh, Eric Olsen, S. P. Singh, J. Manley, F. Wallace

Industrial Technology and Packaging

Corrugated packaging is used to package approximately 90% of all products that reach retail store shelves and aisles in the United States. A large number of these corrugated shippers are used to ship fresh produce and perishables through the cold-chain environment that requires these boxes to have venting to permit air circulation. In addition, corrugated boxes for that are large in size and contain heavier products, may have hand holes to facilitate manual handling. The presence of ventilation and hand holes both cause a loss of material in two or more faces of the box. As a result the compression …

Measurement And Analysis Of Truck Transport Environment In Brazil, Giovani Otavio Rissi, Sher Paul Singh, Gary J. Burgess, Jay A. Singh

Industrial Technology and Packaging

Increasing trade in today’s global economy requires packaging to be designed to contain, protect and deliver products without damage during transportation and handling. Vibration forces that occur during transportation are one of the most significant causes of damage during shipping. The objective of this study was to quantify and analyse the vibration that occurs during truck transport in Brazil. The study was done using two types of trucks: small local trucks for local metropolitan distribution areas and larger tractor-trailers for cross-country transportation. Ten metropolitan areas in different regions of Brazil were selected for 1-day trips representing normal delivery. These trips …

Theory, Simulation, Fabrication And Testing Of Double Negative And Epsilon Near Zero Metamaterials For Microwave Applications, Neil Patel

Master's Theses

Natural structures exhibiting simultaneous negative bulk permittivity and permeability have not yet been discovered. However, research interest over the past five years has grown with the proposition that artificial structures exhibiting these properties are realizable using specially-designed metallic inclusions embedded in host dielectric bodies. A periodic structure of metallic inclusions much smaller than the guided wavelength and embedded in a host dielectric medium is known in the physics and microwave communities as a "metamaterial". Such frequency-dependent effectively homogeneous materials may be designed to exhibit negative permeability and permittivity at certain frequencies. As predicted by electromagnetic theory, such negative index or …

Cfd As Applied To The Design Of Short Takeoff And Landing Vehicles Using Circulation Control, Tyler M. Ball

Master's Theses

The ability to predict the distance required for an aircraft to takeoff is an essential component of aircraft design. It involves aspects related to each of the major aircraft systems: aerodynamics, propulsion, configuration, structures, and stability and control. For an aircraft designed for short takeoffs and landings (STOL), designing the aircraft to provide a short takeoff distance, or more precisely the balanced field length (BFL), often leads to the use of a powered lift technique such as circulation control (CC). Although CC has been around for many years, it has never been used on a production aircraft. This is in …

Development Of A Cell Depositing System Using Inkjet Technology, Jason Robert Ozaeta

Master's Theses

In the past decade, advances in tissue engineering have allowed researchers to fabricate simple tissues. However, the process of creating these native tissues is a time consuming and inefficient process. A scaffold must first be fabricated then exposed to a sea of cells in the hopes of seeding. Furthermore, even though cells may have attached, more time must be spent in order to allow the cells to migrate to their ideal locations. To deal with this problem, researchers have investigated whether rapid prototyping principals could be adapted to facilitate the cell seeding process by placing cells in their respective locations …

Drop Test Reliability Of Lead-Free Chip Scale Packages, Andrew Farris, Jianbiao Pan, Albert Liddicoat, Brian J. Toleno, Dan Maslyk, Dongkai Shangguan, Jasbir Bath, Dennis Willie, David A. Geiger

Industrial and Manufacturing Engineering

This paper presents the drop test reliability of 0.5 mm pitch lead-free chip scale packages (CSPs). Fifteen 0.5 mm pitch CSPs were assembled on a standard JEDEC drop reliability test board with Sn3.0Ag0.5Cu lead-free solder. Eight boards were edge-bonded with a UV-cured acrylic; eight boards were edge- bonded with a thermal-cured epoxy; and twelve boards were assembled without edge bonding. Half of the edge-bonded test boards were subjected to drop tests at a peak acceleration of 1500 G with a pulse duration of 0.5 ms, and the other half subjected to drop tests at a peak acceleration of 2900 G …

Modeling And Simulation Of 6-Pulse And 12-Pulse Rectifiers Under Balanced And Unbalanced Conditions With Impacts To Input Current Harmonics, Arief Hernandi, Taufik, Makbul Anwari

Electrical Engineering

This paper discusses the impact of using 6-pulse and 12-pulse rectifier circuit commonly found in Adjustable Speed Drives. The 12-pulse topology is known to be more expensive, but produce the least input current harmonics. However, the latter statement is completely true under balanced line conditions. In practice, the lines are inherently unbalanced. Hence, the question of whether the 12-pulse rectifier will indeed perform better in terms of the harmonics injected to the line is still under on-going discussions. This paper presents the modeling and simulation of both rectifier topologies to compare their input current harmonics. The rectifiers are modeled using …

Modeling And Simulation Of Paralleled Series-Loaded-Resonant Converter, Alejandro Polleri, Taufik, Makbul Anwari

Electrical Engineering

This paper presents the development of a circuit modeling for paralleled Series Loaded Resonant (SLR) converter used in an experimental power supply to drive high voltage and high frequency medical equipment. The circuit model for each individual converter is first described. Once the complete model of an individual converter is achieved, the model is then extended to include the parallel connection. To verify the validity of model, the design of paralleled SLR using the model is explained. The component values obtained are then being used in Pspice simulations to further prove the validity of the model.

Modeling And Simulation Of Current Ripple In Dc Link Connecting Two Pwm Inverters Using Matlab/Simulink, Taufik, Makbul Anwari

Electrical Engineering

In this paper, the impacts of PWM carrier signals to DC bus current ripple in a PWM-based generator-load system will be investigated. The study is crucial to aid in the determination of the dc bus capacitor in a real-world inverter system. A Simulink model depicting the contribution of the generator current and the load current to the total DC bus current will be described. Results of the computer simulations will also be discussed.

Analysis And Calibration Of Rdii And Design Of Sewer Collection Systems, Misgana K. Muleta, Paul F. Boulos

Civil and Environmental Engineering

Excessive wet weather flow resulting from rainfall-derived inflow and infiltration (RDII) is a major source of sanitary sewer overflows (SSOs). SSOs pose serious problem to the public and the environment by causing back up into basements and sewer overflows to streets and rivers. Control of sewer overflows is, therefore, vital to reducing risks to public health and protecting the environment from water pollution. Computer modeling of sewer collection systems plays an important role in determining sound and economical remedial solutions that reduce RDII, improve system integrity, reliability and performance, and avoid overflows. This paper presents a rigorous and efficient three-step …

Credit-Based Dynamic Reliability Management Using Online Wearout Detection, John Y. Oliver, Rajeevan Amirtharajah, Venkatesh Akella, Frederic T. Chong

Electrical Engineering

As circuit geometries continue to shrink, and supply voltages remain relatively constant, circuit wearout becomes a concern. We propose that the relative reliability of the circuits of a processor be exposed to the operating system, and be managed by a credit-based wearout monitor. This wearout monitor receives dynamic updates of the reliability of circuits through the use of stability detector circuits that are small enough to be widely deployed. We find that through the combined use of the wearout monitor and stability detectors, we can efficiently and accurately manage the reliability of a processor, and re-coup the performance of a …

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 …