Engineering Commons^™

Integrating Qplm And Biomedical Test Data With An Anisotropic Fiber Distribution Model And Predictions Of Tgf-Β1 And Igf-1 Regulation Of Articular Cartilage Fiber Modulus, Michael E. Stender, Christopher B. Raub, Kevin A. Yamauchi, Reza Shirazi, Pasquale Vena, Robert L. Sah, Scott J. Hazelwood, Stephen M. Klisch

Mechanical Engineering

A continuum mixture model with distinct collagen (COL) and glycosaminoglycan elastic constituents was developed for the solid matrix of immature bovine articular cartilage. A continuous COL fiber volume fraction distribution function and a true COL fiber elastic modulus ( Ef) were used. Quantitative polarized light microscopy (qPLM) methods were developed to account for the relatively high cell density of immature articular cartilage and used with a novel algorithm that constructs a 3D distribution function from 2D qPLM data. For specimens untreated and cultured in vitro, most model parameters were specified from qPLM analysis and biochemical assay results; consequently, Ef was …

Consumer Attention To An Over-The-Counter Warning In Four Different Styles Of Design, Abhishek Gawasane, Laura Bix, Javier De La Fuente, Raghav Prashant Sundar, Timothy J. Smith

Industrial Technology and Packaging

The study consisted of three objectives: (a) to test the relative prominence and conspicuousness of a warning required by US law to be conspicuous; (b) to explore whether or not the conspicuousness of the said warning can be enhanced graphically; and (c) to develop preliminary data for power analysis that would guide decisions related to sample size in future studies.

Seventeen subjects viewed four over-the-counter drug packages (each with a different style of warning) along with five other products while wearing an eye tracking device. Four styles of warning were used on the over-the-counter drug packages: no outline and no …

Work In Progress: Outreach Assessment: Measuring Engagement, Lizabeth Schlemer, John Oliver, Katherine Chen, Sophia Rodriguez Mata, Eric Kim

Industrial and Manufacturing Engineering

The Learn By Doing Lab (LBDL) at Cal Poly, San Luis Obispo is an on-campus laboratory where 5th through 8th grade students are taught by undergraduates who may be planning a careers in teaching. The two populations - elementary students and undergraduates - are equally important in the process. Since 2008, the lab has seen over 4000 elementary and junior high students and over 100 undergrads have participated. In most outreach assessment the number of individuals participating is an important metric, but this last Spring we experimented with a more in depth measure of effectiveness. As in any learning experience …

Dynamic Field Test Of A Model Levee Founded On Peaty Organic Soil Using An Eccentric Mass Shaker, E. T. Reinert, S. J. Brandenberg, J. P. Stewart, R. E.S. Moss

Civil and Environmental Engineering

A dynamic field test of a model levee was performed to study the behavior of very soft and compressible peaty organic soils that commonly underlie levees in the Sacramento / San Joaquin Delta in northern California. This first-of-its-kind test applied dynamic loads to the levee/peat system using a large eccentric mass shaker mounted on the levee crest. Loads from the shaker and the inertia of the levee section are transmitted to the peaty organic soils as base shear stresses, and rotational demands that manifest as normal pressures at the embankment/peat interface. We seek to characterize the transmission of seismic energy …

Fundamental Sizing Implications Of Constant Or Increasing Weight Aircraft, Robert A. Mcdonald

Aerospace Engineering

As the energy storage capabilities of batteries and fuel cells advance, these technologies are increasingly being considered for aircraft primary propulsion. In addition to other fundamental differences from conventional systems, these concepts may have constant or even increasing mass throughout the mission. In this paper, the implications of constant or increasing mass on aircraft sizing are considered with the aim of generating insight for the design of these systems.

Dynamic Field Test Of A Model Levee Founded On Peaty Organic Soil Using An Eccentric Mass Shaker, E. T. Reinert, S. J. Brandenberg, J. P. Stewart, R. E.S. Moss

Civil and Environmental Engineering

A dynamic field test of a model levee was performed to study the behavior of very soft and compressible peaty organic soils that commonly underlie levees in the Sacramento / San Joaquin Delta in northern California. This first-of-its-kind test applied dynamic loads to the levee/peat system using a large eccentric mass shaker mounted on the levee crest. Loads from the shaker and the inertia of the levee section are transmitted to the peaty organic soils as base shear stresses, and rotational demands that manifest as normal pressures at the embankment/peat interface. We seek to characterize the transmission of seismic energy …

Sbx7 Flow Rate Measurement Compliance For Agricultural Irrigation Districts, Charles M. Burt, Evan Geer

BioResource and Agricultural Engineering

Senate Bill x7-7 (SBx7-7) requires documented volumetric accounting to individual turnouts for water deliveries. Section 597.3 of the bill lists two very different requirements for devices. This document examines the requirements of SBx7 and the implications for agricultural irrigation districts. The definitions and impacts of flow rate and volumetric accuracy are defined. Example scenarios and solutions are offered, as well as descriptions of applicable devices.

Empirical Model For The Transconductance-Current Dependence Of Short-Channel Mosfets, Vladimir I. Prodanov

Electrical Engineering

This work is concerned with the g_m-I dependence of sub-micrometer MOSFETs. The transconductance-current expression given by the Advanced Compact Model (ACM) is reviewed and simple modification is proposed. The modification yields an expression which (with proper parametrization) captures the g_m-I dependence of short-channel MOSFETs. The proposed expression is “universal” in the sense that it is capable of modeling the g_m-I dependence of long-channel MOSFETs, short-channel MOSFETs, and resistively-degenerated BJTs.

Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank

STAR Program Research Presentations

Jupiter’s satellite Europa, whose surface is composed of ice with a possible water ocean beneath, could conceivably serve as an abode for extraterrestrial life. This and other icy celestial bodies may contain organic macromolecular solid material that is produced when surface ices are exposed to ultraviolet radiation and/or electrical energy. Tidal and tectonic stresses or meteorite impacts in icy crusts may produce electrical discharges, which would provide the energy for in-situ synthesis of the organic solids. This electrical energy can be provided by positive hole charge carrier activation. Positive holes exhibit properties such as the ability to flow out of …

Technology Portal For Energy Efficient Buildings, Larry D. Hermanson, Daniel Studer, Annie Mroz

STAR Program Research Presentations

Project: Technology Portal for Energy Efficient Buildings

Date: August 2, 2012

Author: Larry Hermanson

Mentor: Daniel Studer

Cohort: Annie Mroz

Lab site: National Renewable Energy Laboratory (NREL)

Buildings account for 71% of the electricity demand and 39% of the primary energy consumption in the United States. The Commercial Buildings Group at NREL provides builders, designers and building owners accurate information to significantly improve the energy efficiency of new and existing buildings. The Technology Portal for Energy Efficient Buildings will increase the accessibility of standardized and credible energy performance data for all building systems, thereby allowing building owners to better evaluate …

Graphene Refinement By High Temperature Anneals, Benjamin A. Calvopina, Justin Bult, Jeff Blackburn

STAR Program Research Presentations

Graphene’s intrinsic properties of being a good conductor as well as having efficient optical transmission make it a potentially useful material in photovoltaic cells as a transparent conducting electrode. One problem preventing graphene from being fully utilized stems from contaminates created and deposited during the transfer process of multiple graphene layers. After synthesis, TRT (Thermal Release Tape) is applied to the graphene supported on the copper growth substrate. TRT utilizes a unique formulation of adhesive that is temperature sensitive so that it will release when heated. Upon removing the growth substrate in a chemical bath, the TRT is used to …

Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett

STAR Program Research Presentations

Hydrogen is an attractive energy option because of its low
environmental impact, but a critical problem is its low energy
density, which makes it difficult to store. For example, the US
Department of Energy (DOE) hydrogen plan for fuel cell powered
vehicles requires a gravimetric density of 6.5 wt%. There are several
existing hydrogen storage methods, including compressed gas,
liquefaction, metal hydrides, and physisorption, but at present, none
of these technologies comes close to achieving the targets set by the
DOE. Although chemical storage methods have been claimed to be the
most promising hydrogen storage technology, and activated carbons the …

Telescope Assembly Alignment Simulator Performance Optimization, Joshua G. Thompson, Brian Eney, Zaheer Ali, Bob Thompson

STAR Program Research Presentations

The Telescope Assembly Alignment Simulator (TAAS) calibrates scientific instruments (SI’s) that are installed on the Stratospheric Observatory For Infrared Astronomy (SOFIA). An SI’s accuracy is directly dependent on the consistent performance of the TAAS, which has never been fully characterized. After designing various thermal and optical experiments to identify the current unknowns of TAAS, we now have a far better grasp on how the equipment behaves.

Effects Of Sprinkler, Partial Sprinkler/Drip, And Drip Only Irrigation On Strawberry Transplants 2011-2012, Stuart Styles

BioResource and Agricultural Engineering

The Cal Poly Irrigation Training and Research Center (ITRC), in collaboration with academic, water district, and industry partners, proposes to evaluate new strategies for drip irrigation on strawberries to minimize runoff during transplant establishment.

The most common method used for irrigating strawberries is a mix of sprinkler irrigation and drip. Growers use sprinkler irrigation for bed preparation and salinity control, then eventually switch to drip irrigation after transplanting, but continue to use sprinkler irrigation as an insurance policy (for bonding between plant roots and soil bonding, washing off the leaves, controlling salinity, and frost). However, field observations have shown that …

Commissioning Of The Asta Laser Lab With Uv Pulse Length Characterization, Daniel Kelley, Jeff Corbett

STAR Program Research Presentations

The Linac Coherent Light Source (LCLS) at SLAC depends on a photocathode electron gun to provide the linear accelerator with the raw material – electrons – used for making X-ray laser pulses. The photocathode used in the LCLS Injector is a clean copper plate in high vacuum. When the cathode is struck with high energy UV light, electrons are liberated from its surface and then accelerated down the linac with radio-frequency electric fields. These fast-moving bunches of electrons are directed through an undulator magnet to radiate X-ray light.

Although scientists have been using photocathode techniques at SLAC for 25 years, …

Selective Laser Sintering; A Design Of Experiments, Philip David Hopkins, Victor Castillo Phd

STAR Program Research Presentations

Additive Manufacturing (AM), also commonly known as 3D Printing or Rapid Prototyping, is a method of manufacturing that provides for the ability to make intricate internal features and easily customizable parts. The concept is to break a Computer Aided Design (CAD) file into a series of thin layers that are sent to the machine and laid down one layer at a time. Just like any other form of processing, material properties can alter by undergoing this process. Manipulating various parameters of the AM process can allow for different properties to be achieved. For this reason, an in depth study will …

Structural Damage Detection Using Artificial Neural Networks And Wavelet Transform, Arthur Shi, Xiao-Hua Yu

Electrical Engineering

With the ever-increasing demand for the safety and functionality of civil infrastructures, structure health monitoring (SHM) has now become more and more important.

Recent developments in computational intelligence and digital signal processing offer great potentials to develop a more efficient, reliable, and robust structure damage identification system. In this paper, the application of artificial neural networks and wavelet analysis is investigated to develop an intelligent and adaptive structural damage detection system. The proposed approach is tested on an IASC (International Association for Structural Control)-ASCE (American Society of Civil Engineers) SHM benchmark problem. Satisfactory computer simulation results are obtained.

Implementation Of Magnetic Meters For Irrigation Volumetric Measurement, Stuart Styles, Lynn Groundwater

BioResource and Agricultural Engineering

The irrigation industry is experiencing a growth in the use of magnetic meters for measuring the flow rate and volume in irrigation pipelines. Historically, propeller meters have been the device selected by users. New legislation in California (SB7x7) will require measurement devices at key locations for irrigation water delivery. Some users are very interested in the magnetic meter for making the measurement at the turnout or farm gate. The key feature of the new meter is the ability for the device to work in less than ideal flow conditions. Electromagnetic meters have been tested by the Irrigation Training and Research …

Traffic Signal Optimization Using Ant Colony Algorithm, David Renfrew, Xiao-Hua Yu

Electrical Engineering

Traffic signal control is an effective way to improve the efficiency of traffic networks and reduce users’ delays. Ant Colony Optimization (ACO) is a meta-heuristic algorithm based on the behavior of ant colonies searching for food. ACO has successfully been employed to solve many complicated combinatorial optimization problems and its stochastic and decentralized nature fits well with traffic networks. This research investigates the application of the ant colony algorithm to minimize user delay at traffic intersections. Various ACO algorithms are discussed and a rolling horizon approach is also employed to achieve real-time adaptive control. Computer simulation results show that this …

Challenges In Transdisciplinary, Integrated Projects: Reflections On The Case Of Faculty Members’ Failure To Collaborate, Linda Vanasupa, Kathryn E. Mccormick, Carolyn J. Stefanco, Roberta J. Herter, Margot Mcdonald

Materials Engineering

In this article we describe the challenges of transdisciplinary teamwork involving four faculty members from dissimilar epistemological traditions in the process of developing a manuscript on the lessons learned in our teaching collaboration. Our difficulty originated in implicit mental models and assumptions that caused incongruence between our intent to collaborate and the (habituated) relationship structure of the partnership. The dynamics are described through the lens of Tannenbaum and Schmidt’s leadership model and Aristotle’s causality. We suggest that successful collaboration necessitates careful attention to the process of establishing the collaboration, its structure, and the metacognitive capacities to see one’s own thinking, …

Model Performance Sensitivity To Objective Function During Automated Calibrations, Misgana Muleta

Civil and Environmental Engineering

Previous studies have reported limitations of the efficiency criteria commonly used in hydrology to describe goodness of model simulations. This study examined sensitivity of model performance to the objective function used during automated calibrations. Nine widely used efficiency criteria were evaluated for their effectiveness as objective function, and goodness of the model predictions were examined using 13 criteria. Two cases (Case I: Using observed streamflow data and Case II: Using simulated streamflow) were considered to accomplish objectives of the study using a widely used watershed model (SWAT) and good-quality field data from a well-monitored experimental watershed. Major findings of the …

Coseismic Tectonic Surface Deformation During The 2010 Maule, Chile, MW 8.8 Earthquake, Keith Kelson, Robert C. Witter, Andrés Tassara, Isabelle Ryder, Christian Ledezma, Robb Moss, Laurie Johnson

Civil and Environmental Engineering

Tectonic deformation from the 2010 Maule (Chile) M_w 8.8 earthquake included both uplift and subsidence along about 470 km of the central Chilean coast. In the south, deformation included as much as 3 m of uplift of the Arauco Peninsula, which produced emergent marine platforms and affected harbor infrastructure. In the central part of the deformation zone, north of Constitución, coastal subsidence drowned supratidal floodplains and caused extensive shoreline modification. In the north, coastal areas experienced either slight uplift or no detected change in land level. Also, river-channel deposition and decreased gradients suggest tectonic subsidence may have occurred in …

The Synergistic Integration Of Computational Fluid Dynamics And Experimental Fluid Dynamics For Ground Effect Aerodynamics Studies, Tj Barber, G Doig, C Beves, I Watson, S Diasinos

Aerospace Engineering

This article highlights the ‘synergistic’ use of experimental fluid dynamics (EFD) and computational fluid dynamics (CFD), where the two sets of simulations are performed concurrently and by the same researcher. In particular, examples from the area of ground effect aerodynamics are discussed, where the major facility used was also designed through a combination of CFD and EFD. Three examples are than outlined, to demonstrate the insight that can be obtained from the integration of CFD and EFD studies. The case studies are the study of dimple flow (to enhance aerodynamic performance), the analysis of a Formula-style front wing and wheel, …

Aerodynamics Of An Aerofoil In Transonic Ground Effect: Methods For Blowdown Wind Tunnel Scale Testing, G. Doig, T. J. Barber, A. J. Neely, D. D. Myre

Aerospace Engineering

No abstract provided.

A Formal Bayesian Approach For Uncertainty Analysis Of A Watershed Model, Misgana K. Muleta

Civil and Environmental Engineering

Uncertainty analysis (UA) has received substantial attention in water resources during the last decade. Bayesian approaches are often preferred for UA. This study describes a formal Bayesian approach for the assessment of parameter uncertainty and predictive uncertainty using a spatially distributed hydrologic model and will demonstrate its application using data from a well monitored experimental watershed. A Markov-Chain Monte Carlo (MCMC) scheme has been used to sample posterior parameter distributions. A formal, flexible likelihood function that explicitly accounts for heteroscedasticity, temporal correlation and non-normality of simulation residuals has been used to describe closeness of the simulated and observed streamflow. Performance …

Approaches To Control Nitrate Pollution In The San Joaquin Watershed, Misgana K. Muleta, Stephen Clayton

Civil and Environmental Engineering

No abstract provided.

Evaluating Alternative Hydraulic Solutions To Limit Nutrient Contamination Of An Aquifer In Southern California, Jake M. Perry, Misgana K. Muleta

Civil and Environmental Engineering

Many small communities depend on groundwater sources for drinking water and they often use septic tanks for wastewater treatment and disposal. Nitrate and other pollutants leaking from poorly designed septic tank systems can percolate to the aquifers and alter quality of the groundwater. This study describes a groundwater model developed using Visual MODFLOW for an aquifer that is used as a water supply source for the communities of Beaumont and Cherry Valley, CA. The aquifer has been contaminated by nitrates leaking from septic tank systems. The model will assist in clarifying the extent of interactions between nitrate pollutants, percolation from …

Uncertainty Analysis And Calibration Of Swmm Using A Formal, Bayesian Methodology, Misgana K. Muleta

Civil and Environmental Engineering

Importance of uncertainty analysis (UA) to estimate the degree of reliability associated with model predictions is being understood. Consequently, literature that describes various Bayesian methods for the assessment of parameter and model predictive uncertainty has been steadily rising. Applications dealing with urban stormwater management are, however, very limited. This study demonstrates successful application of a formal Bayesian methodology for UA of the U.S. EPA Stormwater Management Model (SWMM), a widely used urban stormwater management model, and illustrates the methodology using a highly urbanized watershed in southern California. DREAM(ZS), a recently developed effective and efficient sampling algorithm, and a generalized, formal …

Assessing Lean Systems Using Variability Mapping, Ahmed Deif

Industrial Technology and Packaging

A new approach to assess lean manufacturing based on system's variability is proposed. The assessment utilizes a new tool called variability source mapping (VSMII) which focuses on capturing and reducing variability across the production system. The new tool offers a new metric called variability index to measure the overall variability level of the system. Based on the mapping and the new metric, VSMII suggests a variability reduction plan guided by a recommendation list of both lean techniques as well as production control policies. An industrial application is used to demonstrate the new tool. Results show that VSMII managed to reduce …

Discussion Of “Comparison Of Base Shears Estimated From Floor Accelerations And Column Shears”, Rakesh K. Goel

Civil and Environmental Engineering

In lieu of a provided abstract, the first paragraph is provided:

The author agrees with Dr. Pinho about difficulties associated with the use of different damping models in nonlinear dynamic analysis. However, the focus of the original manuscript was to illustrate the difference between base shear estimated from floor accelerations, denoted as inertial base shear, and base shear estimated from column shears, denoted as the structural base shear. The difference between the two base shears exists regardless of the damping model used in the nonlinear analysis. In order to illustrate this conclusion, the Los Angeles building of the original manuscript …