Engineering Commons^™

Supervised Machine Learning For Classification Of The Electrophysiological Effects Of Chronotropic Drugs On Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes, Christopher Heylman, Rupsa Datta, Agua Sobrino, Steven George, Enrico Gratton

Biomedical Engineering

Supervised machine learning can be used to predict which drugs human cardiomyocytes have been exposed to. Using electrophysiological data collected from human cardiomyocytes with known exposure to different drugs, a supervised machine learning algorithm can be trained to recognize and classify cells that have been exposed to an unknown drug. Furthermore, the learning algorithm provides information on the relative contribution of each data parameter to the overall classification. Probabilities and confidence in the accuracy of each classification may also be determined by the algorithm. In this study, the electrophysiological effects of β–adrenergic drugs, propranolol and isoproterenol, on cardiomyocytes derived from …

Geotechnical Effects Of The 2015 Magnitude 7.8 Gorkha, Nepal, Earthquake And Aftershocks, Robb E.S. Moss, Eric M. Thompson, D. Scott Kieffer, Binod Tiwari, Youssef M.A. Hashash, Indra Acharya, Basanta Raj Adhikari, Domniki Asimaki, Kevin B. Clahan, Brian D. Collins, Sachindra Dahal, Randall W. Jibson, Diwakar Khadka, Amy Macdonald, Chris L.M. Madugo, H. Benjamin Mason, Menzer Pehlivan, Deepak Rayamajhi, Sital Uprety

Civil and Environmental Engineering

This article summarizes the geotechnical effects of the 25 April 2015 M 7.8 Gorkha, Nepal, earthquake and aftershocks, as documented by a reconnaissance team that undertook a broad engineering and scientific assessment of the damage and collected perishable data for future analysis. Brief descriptions are provided of ground shaking, surface fault rupture, landsliding, soil failure, and infrastructure performance. The goal of this reconnaissance effort, led by Geotechnical Extreme Events Reconnaissance, is to learn from earthquakes and mitigate hazards in future earthquakes.

Evaluation Of In-Ground Plastic-Hinge Length And Depth For Piles In Marine Oil Terminals, Rakesh K. Goel

Civil and Environmental Engineering

This investigation evaluated the current recommendations for plastic-hinge length and depth for piles in marine oil terminals considering nonlinear pile and soil behavior, as well as two seismic design levels: Level 1 and Level 2. It was found that the plastic-hinge length depends on seismic design level, whereas depth is independent of seismic design level. For pre-stressed concrete piles, the current plastic-hinge length recommendations were generally found to be adequate for seismic design Level 2, but provided much smaller plastic-hinge length for Level 1. For hollow-steel piles, the current plastic-hinge length recommendation was generally found to be adequate for sands, …

Reconstructing The Natural Hydrology Of The San Francisco Bay - Delta Watershed, P. Fox, P.H. Hutton, D.J. Howes, A.J. Draper, L. Sears

BioResource and Agricultural Engineering

We evaluated the impact of landscape changes on the amount of delta outflow reaching San Francisco Bay. The natural landscape was reconstructed and water balances were used to estimate the long-term annual average delta outflow that would have occurred under natural landscape conditions if the climate from 1922 to 2009 were to repeat itself. These outflows are referred to as natural delta outflows and are the first published estimate of natural delta outflow. These natural delta outflows were then compared with current delta outflows for the same climate and existing landscape, including its re-engineered system of reservoirs, canals, aqueducts, and …

Reducing Transonic Wind Tunnel Sting Interference Effects For Concealed Store Release Testing, Graham Doig, Goran Bogdan, Kaveh R. Kabir, Murray R. Snyder

Aerospace Engineering

Internal weapons bays are becoming increasingly common on aircraft for reasons of stealth and aerodynamic performance, and will be even more prevalent on coming generations of unmanned combat aerial vehicles (UCAVs). Wind tunnel testing of store releases to assess forces and moments for safety and clearance must be conducted with a store mounted to an angled strut rather than a conventional rear sting, to allow the full range of motion as the store “drops” from inside the aircraft. Interference from this strut can disrupt the flowfields and thus the reliability of moments obtained, and therefore an investigation was conducted to …

The Effects Of Simplifications On Isolated Wheel Aerodynamics, Sammy Diasinos, Tracie Barber, Graham Doig

Aerospace Engineering

In order to study the aerodynamic forces and flow features of rotating wheels, compromises and simplifications are often made in wind tunnel testing, and more frequently so in numerical modelling. A CFD approach similar to that commonly used in industry was utilised to investigate common assumptions involving; the influence of geometric fidelity in wheel hub regions, ground representation, the modelling of the contact patch, and the effects of rotation on separation. It was found that the separation and wake characteristics were strongly influenced by the rotation of the wheel; the separation point changed by as much as 90% compared to …

Implications Of Variable Waste Placement Conditions For Msw Landfills, Jason T. Cox, Nazli Yesiller, James L. Hanson

Civil and Environmental Engineering

This investigation was conducted to evaluate the influence of waste placement practices on the engineering response of municipal solid waste (MSW) landfills. Waste placement conditions were varied by moisture addition to the wastes at the time of disposal. Tests were conducted at a California landfill in test plots (residential component of incoming wastes) and full-scale active face (all incoming wastes including residential, commercial, and self-delivered components). The short-term effects of moisture addition were assessed by investigating compaction characteristics and moisture distribution and the long-term effects by estimating settlement characteristics of the variably placed wastes. In addition, effects on engineering properties …

Design Of High-Area-Ratio Nozzle Contours Using Circular Arcs, K. Schomberg, J. Olsen, Graham Doig

Aerospace Engineering

A method using circular arcs to generate the divergence contour in a supersonic nozzle is presented. Comparison of the arc-based geometry with existing nozzle contours demonstrated that an average decrease in axial length of 7.5% can be expected when the arc-based design method is applied to a core stage nozzle. Two arc-based and conventional nozzles were evaluated numerically across the pressure operating range of a core stage engine to compare calculated thrust and separation characteristics with existing data. The length-weighted thrust coefficient was increased by 0.3–1.8% in the arc-based design in both configurations. Separated flow characteristics were compared using contours …

Mapping Kinematic Functional Abilities Of The Hand To Three Dimensional Shapes For Inclusive Design, Samuel T. Leitkam, Laura Bix, Javier De La Fuente, Tamara Reid Bush

Industrial Technology and Packaging

Loss of hand function can have adverse effects on an individual's ability to maintain independence. The ability to perform daily activities, such as food preparation and medication delivery, is dependent on the hand's ability to grasp and manipulate objects. Therefore, the goal of this research was to demonstrate that three dimensional (3D) modeling of hand function can be used to improve the accessibility of handheld objects for individuals with reduced functionality through informed design. Individual models of hand functionality were created for 43 participants and group models were developed for groups of individuals without (Healthy) and with reduced functionality due …

The Influence Of Cu3(Btc)2 Metal Organic Framework On The Permeability And Perm-Selectivity Of Plla-Mof Mixed Matrix Membranes, Ajay Kathuria, Saleh Al-Ghamdi, Mohamad G. Abiad, Rafael Auras

Industrial Technology and Packaging

Poly(l-lactic acid) (PLLA) - 20% (w/w) and Cu₃(BTC)₂ metal organic framework (MOF) based mixed matrix membranes (MMMs) were fabricated by a vertical corotating twin screw microcompounder followed by an injection molding process. Water vapor, CO_2, O₂, and selected aroma mass transfer properties of PLLA and PLLA MMMs were evaluated. The CO₂/O₂ perm-selectivity of PLLA (α_CO2/O2) MMMs increased from 7.6 to 10.3 with the incorporation of 20% Cu₃(BTC)₂ MOF. Gravimetric permeability studies of trans-2-hexenal performed at 23°C and 50% RH indicated that permeability coefficient of PLLA MMMs …

Geotechnical Field Reconnaissance: Gorkha (Nepal) Earthquake Of April 25, 2015 And Related Shaking Sequence, Youssef M.A. Hashash, Binod Tiwari, Robb E.S. Moss, Domniki Asimaki, Kevin B. Clahan, D. Scott Kieffer, Doug S. Dreger, Amy Macdonald, Chris M. Madugo, H. Benjamin Mason, Menzer Pehlivan, Deepak Rayamajhi, Indra Acharya, Basanta Adhikari

Civil and Environmental Engineering

The April 25, 2015 Gorkha (Nepal) Earthquake and its related aftershocks had a devastating impact on Nepal. The earthquake sequence resulted in nearly 9,000 deaths, tens of thousands of injuries, and has left hundreds of thousands of inhabitants homeless. With economic losses estimated at several billion US dollars, the financial impact to Nepal is severe and the rebuilding phase will likely span many years. The Geotechnical Extreme Events Reconnaissance (GEER) Association assembled a reconnaissance team under the leadership of D. Scott Kieffer, Binod Tiwari and Youssef M.A. Hashash to evaluate geotechnical impacts of the April 25, 2015 Gorkha Earthquake and …

Comparison Of Beta Backscatter And X-Ray Fluorescence Methods To Measure Coating Thickness, Sergio Palomo, Bernice Mills

STAR Program Research Presentations

This work compares and assesses the effectiveness of beta backscatter (BB) and x-ray fluorescence (XRF) for measuring the thickness of gold coatings on two substrates: silicon and an iron-nickel alloy. A set of samples of known gold coating thickness, ranging from 0.5 – 4.0 microns, was measured in each case along with the substrate alone. In BB the number of electrons (beta particles from a very small radioactive source, Pm-147 in this case) backscattered from a sample in a fixed time period is counted. The XRF method uses x-rays generated in the sample from a primary x-ray beam of higher …

Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell

STAR Program Research Presentations

Pacific Northwest National Laboratory (PNNL) is currently developing an ultra-low background liquid scintillator counter (ULB LSC) in the shallow underground laboratory. At a depth of 35-meters water-equivalent, the underground laboratory has a multi-layered shielding to keep out cosmic-ray induced background. The ULB LSC, which is located in a clean room facility, is a multi-layered design made up of various materials, including plastic scintillator veto panels, borated polyethylene, lead and copper. These layers help lower the contributions of the terrestrial background and intrinsic background, resulting from the impurities present in the materials, to the overall background count rate observed by the …

Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-Nguyen, Bernice Mills

STAR Program Research Presentations

X-rays are widely used in medicine and materials science to identify impurities or fractures within the target object. In material science, x-rays can be used to identify the thickness of samples with different material densities. The current method is to collect a radiograph using estimated conditions, evaluate the results, then make changes to the conditions. The residual image can be rescanned making it possible to obtain an image of lower radiographic density. By tabulating or graphing the effects of energy changes and rescans, a more informed choice of conditions is possible.

For this study, six materials were chosen with a …

Effect Of Surface Omniphobicity On Drying By Forced Convection, Madani A. Khan, Jeffrey Alston, Andrew Guenthner

STAR Program Research Presentations

Low energy surfaces can strongly repel both oil and water. Recently these surfaces have been fabricated on various substrates including fabric, aluminum, stainless steel and many other materials. In this experiment we explore the use of low energy surface deposition on aluminum alloy, stainless steel and silicon substrates, to enhance the drying rate of liquids removed from the surface by forced convection. We control surface roughness by substrate abrasion and by the growth of Al₂O₃ nanograss to enhance liquid repellence by use of a hierarchical texture. Liquid repellence of the substrates is measured by contact angles of …

Wet Chemical Synthesis And Characterization Of Nanomaterials For Solar Cell Applications, Krystle N. Sy, Ramprasad Gandhiraman, Jessica E. Koehne

STAR Program Research Presentations

During long term space missions, it is necessary to have a reliable source of energy. Solar cells are an easy and reliable way to convert energy from the sun to electrical energy. NASA has used solar cells manufactured on Earth as an energy source for many of its missions. In order to develop technologies that will enable high efficiency solar cells, we are synthesizing nanostructured materials. A range of nanostructured materials, such as titanium dioxide nanowires, nickel nanoparticles, copper nanoparticles, and silver nanoparticles/nanowires, are synthesized. In this work, we are reporting on the synthesis of these nanomaterials and the electron …

Radiographic Density Of Selected Materials At Different Thicknesses, Thien Quang Vu-Nguyen, Bernice Mills

STAR Program Research Presentations

X-rays are widely used in medicine and materials science to identify impurities or fractures within the target object. In material science, x-rays can be used to identify the thickness of samples with different material densities. The current method is to collect a radiograph using estimated conditions, evaluate the results, then make changes to the conditions. The residual image can be rescanned making it possible to obtain an image of lower radiographic density. By tabulating or graphing the effects of energy changes and rescans, a more informed choice of conditions is possible.

For this study, six materials were chosen with a …

Designing A Remote Aerial System To Image And Analyze The Health Of Grape Crops At Cal Poly San Luis Obispo, Alexander D. Vice, Dylan Benton, Adipratnia Asmady, Andrew Mercier, Andrew Meyer, Eric Belfield, Aaron Drake

STAR Program Research Presentations

In the last decade the prevalence of unmanned aerial vehicles (UAVs) has exploded; however, the presence of UAVs in research situations is still a relatively new and untested field. The autonomous flight lab (AFL) at Cal Poly San Luis Obispo is a new lab site that is dedicated to using UAVs to benefit research for all backgrounds. Before AFL was able to fly missions we first needed to actually receive our vehicles, create a lab space that would provide all of the necessary resources and equipment necessary to fly, and to be granted permission by the Federal Aviation Administration (FAA) …

Rating Rectangular Farm Delivery Meter Gates For Flow Measurement, Daniel J. Howes, Charles M. Burt

BioResource and Agricultural Engineering

Traditional meter gates for farm delivery flow measurement from an open channel conveyance have traditionally incorporated round canal gates (Armco type) for control. In recent years, some irrigation water agencies (i.e., irrigation districts) have replaced deteriorating round gates with lower-cost rectangular gates that cover round holes. Similar to the situation described in a companion paper, where round gates were examined, there have been no investigations into flow measurement uncertainty using the existing rating tables for these gates. In this study, two commonly used rectangular gate sizes, 0.46 m (18-in.) and 0.61 m (24-in.), were tested under scenarios of various gate …

Accuracy Of Round Meter Gates For On-Farm Deliveries, Daniel J. Howes, Charles M. Burt

BioResource and Agricultural Engineering

Recent California legislation requires irrigation water agencies larger than 25,000 acres to measure volumetric water deliveries within specified levels of relative uncertainty. Although the meter gate is one of the most widely used flow measurement devices in California, little investigation has been conducted into the accuracy, limitations, and uncertainties of the rating tables developed over 60 years ago. A meter gate testing facility was constructed at the Cal Poly Irrigation Training and Research Center’s Water Resources Facility capable of testing gates up to 0.76 m (30 in.). The facility was constructed with gates oriented perpendicular to the supply channel flow …

How To Save The World: One Life (And Uav) At A Time!, Natalie A. Wright

STAR Program Research Presentations

The proliferation of Uninhabited Aerial Vehicles (UAV’s) in commercial and public service aviation arenas has begun to gain the attention of many citizens. Popularized vehicles such as quadcopters have applications in aerial photography, small package delivery and hobbyist/consumer interests. Use of small-scale, fixed- and rotary-wing, remotely operated systems has been popularized as a result of such vehicles’ size and operational simplicity, which widens the range of application of this technology. Public service applications have the potential to advance emergency services management, which can substantially contribute to the public wellbeing. This research will examine the utility of multi-rotor systems in the …

Improving Flow Measurement Accuracy At Farm Delivery Gates In California, Charles M. Burt, Daniel J. Howes

BioResource and Agricultural Engineering

ITRC, through a CSU ARI grant, constructed a meter gate testing facility and tested five gates of various sizes and designs. The gate testing was conducted by varying the multiple parameters including upstream and downstream head, supply channel velocity, gate opening, and head above the gate. Data was also collected at various locations on the downstream side of the gate. In total, ITRC staff collected over 10,000 points of data during this evaluation. Using the new rating tables for the three gates examined, the relative uncertainty is less than ±5 to ±7% at the 95% confidence level with the new …

Design And Implementation Of An Instrumented Pedal For Cycling Biomechanics Research, Luke I. Kraemer, Juan D. Gutierrez-Franco, Jake E. Deschamps, Karim C. Dudum, Eshan M. Dandekar, Scott Hazelwood, Hemanth Porumamilla, Stephen M. Klisch

Biomedical Engineering

Cycling is a common, low-impact activity used for recreation, exercise, and rehabilitation. Knee joint loading can be predicted using inverse dynamic analyses of pedal load cell and kinematic data measured during cycling biomechanics experiments. Several studies have successfully measured foot loading at the pedals, e.g. by using custom instrumented pedal spindles outfitted with strain gauges and a potentiometer to measure crank angle [1-3]. Such designs are relatively complex, requiring difficult machining and component fabrication, and require post-processing of strain gauge data.

The long-term goal of this study is to calculate knee joint loading and, ultimately, cartilage tissue stress to provide …

Human Knee Joint Finite Element Model Using A Two Bundle Anterior Cruciate Ligament: Validation And Gait Analysis, Nicholas A. Czapla, Meghan K. Sylvia, Zachary F. Lerner, David J. Tuttle, Otto J. Schueckler, S. J. Hazelwood, Stephen M. Klisch

Biomedical Engineering

Anterior cruciate ligament (ACL) deficient individuals are at a much higher risk of developing osteoarthritis (OA) compared to those with intact ACLs, likely due to altered biomechanical loading [1]. Research indicates the ACL is comprised of two “bundles”, the anteromedial (AM) and posterolateral (PL) bundles [2]. Although the function of both bundles is to restrain anterior tibial translation (ATT), each bundle has their own distinct range of knee flexion where they are most effective [3].

Articular cartilage contact stress measurements are difficult to measure in vivo. An alternative approach is to use knee joint finite element models (FEMs) to predict …

Development Of A Human Knee Joint Finite Element Model To Investigate Cartilage Stress During Walking In Obese And Normal Weight Adults, Meghan K. Sylvia, Nicholas A. Czapla, Zachary F. Lerner, David J. Tuttle, Otto J. Schueckler, Scott Hazelwood, Stephen M. Klisch

Biomedical Engineering

Osteoarthritis (OA) is a degenerative condition characterized by the breakdown and loss of joint articular cartilage. While the cause of OA is not precisely known, obesity is a known risk factor [1]. Particular effort has gone towards understanding the relationship between obesity and knee OA because obesity is more strongly linked to OA at the knee than at any other lower extremity joint [2]. Although the relationship between obesity and knee OA is well established, the mechanism of pathogenesis is less understood. Excess body weight generates greater joint contact forces at the knee. However, obese individuals alter their gait, resulting …

Using Opensim To Predict Knee Joint Moments During Cycling, Karim C. Dudum, Jake E. Deschamps, Juan D. Gutierrez-Franco, Luke I. Kraemer, Alejandro M. Gonzalez-Smith, Eshan M. Dandekar, S. J. Hazelwood, Stephen M. Klisch

Biomedical Engineering

Cycling is a relatively low impact activity conventionally recommended as a rehabilitative or fitness sustaining exercise for patients at a high risk for knee osteoarthritis (OA) [1,2]. Expanding our understanding of knee joint loads is necessary to develop and improve evidence-based prescriptions for cycling as a rehabilitative and fitness therapy that limits the risk for knee OA.

OpenSim (www.simtk.org) is an open source biomechanical analysis software that can partition predictions of external joint loads (or net muscle moments) into muscle and joint contact loads [3]. Joint contact loads more accurately represent cartilage tissue loading and hence risk for cartilage damage …

Design And Implementation Of An Instrumented Pedal For Cycling Biomechanics Research, Luke I. Kraemer, Juan D. Gutierrez-Franco, Jake E. Deschamps, Karim C. Dudum, Eshan M. Dandekar, Scott Hazelwood, Hemanth V. Porumamilla, Stephen M. Klisch

Mechanical Engineering

No abstract provided.

Human Knee Joint Finite Element Model Using A Two Bundle Anterior Cruciate Ligament: Validation And Gait Analysis, Nicholas A. Czapla, Meghan K. Sylvia, Zachary F. Lerner, David J. Tuttle, Otto J. Schueckler, Scott J. Hazelwood, Stephen M. Klisch

Mechanical Engineering

No abstract provided.

Pseudo-Rigid Body Method For Reducing Soft Tissue Artifact: Validation And Application To Gait, Jake E. Deschamps, Karim C. Dudum, Eshan M. Dandekar, Scott Hazelwood, Stephen M. Klisch

Mechanical Engineering

No abstract provided.

Using Opensim To Predict Knee Joint Moments During Cycling, Karim C. Dudem, Jake E. Deschamps, Juan D. Gutierrez-Franco, Luke I. Kraemer, Alejandro M. Gonzalez-Smith, Eshan M. Dandekar, Scott Hazelwood, Stephen M. Klisch

Mechanical Engineering

No abstract provided.