Engineering Commons^™

Bs News May/June

Building Services Engineering

No abstract provided.

Fluidized-Bed Gasification Of Dairy Manure By Box–Behnken Design, Hanjing Wu, Milford A. Hanna, David D. Jones

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Application of excessive animal manure to the land may cause some environmental problems such as eutrophication of surface waters, degradation of ground water quality, and threats to human health. This paper reports an experimental study on the technology of biomass gasification to treat animal waste by analyzing the effects of key operating parameters on gasification. In this research, dairy manure from the University of Nebraska dairy farm was first collected and dried, and then gasified in a fluidized-bed, laboratory-scale gasifier to generate syngas. The effects of three parameters, namely temperature, steam to biomass ratio (SBR) and the equivalence ratio (ER), …

Mapping Spatially Interpolated Precipitation, Reference Evapotranspiration, Actual Crop Evapotranspiration, And Net Irrigation Requirements In Nebraska: Part I. Precipitation And Reference Evapotranspiration, Vivek Sharma, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Precipitation and reference evapotranspiration are two important variables in hydrologic analyses, agricultural crop production, determining actual crop evapotranspiration and irrigation water requirements, and irrigation management. Both variables vary in space and time, and the weather networks that measure or quantify and report both variables are too sparse for practical applications by water resources planners, managers, and irrigators. Long-term (1986- 2009) average annual (January to December), seasonal (growing season, May to September), and monthly (May, June, July, August, and September) precipitation and Penman-Monteith-estimated alfalfa-reference evapotranspiration (ET_ref) were spatially interpolated and mapped for all 93 counties in Nebraska using the …

Nutrient Losses In Runoff From Feedlot Surfaces As Affected By Unconsolidated Surface Materials, John E. Gilley, Jason R. Vogel, Roger A. Eigenberg, David B. Marx, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Beef cattle feedlots contain unconsolidated surface materials (loose manure pack) that accumulate during a feeding cycle. The effects of varying amounts of unconsolidated surface materials on runoff nutrient losses are not well understood. The objectives of this study were to (1) compare runoff nutrient losses from feedlot surfaces containing varying amounts of unconsolidated surface materials, (2) determine if differences in runoff nutrient losses exist among rainfall simulation runs, (3) relate runoff nutrient losses to selected feedlot soil characteristics, and (4) identify the effects of varying runoff rate on nutrient loss rates from feedlot surfaces. This study was conducted on 0.75 …

Investigation Of Relative Importance Of Some Error Sources In Particle Image Velocimetry, Jeff R. Harris

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Particle image velocimetry (PIV) is an optical technique used to measure fluid velocity. PIV measurements have many sources that create uncertainty in the velocity results. The objective of this report is to investigate some commonly cited uncertainty sources and to show methods than can be used to find the value of the uncertainty sources. These sources are: magnification, calibration, perspective, resolution and the computation scheme. Experiments were conducted to find the impact that sources have on the velocity measurements. Several methods are presented to demonstrate how to measure the uncertainty of error for a PIV experiment. Some error quantities are …

Effect Of Orifice Shape On Synthetic Jet Efficiency, David J. Nani

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A synthetic jet is formed by periodic oscillation of a fluid through an orifice. The oscillatory motion is driven by diaphragm or other driver. Previous studies have demonstrated that synthetic jet formation and time-averaged cavity pressure are a function of the orifice shape. Traditionally, the performance of the jet is evaluated with varying configurations of fixed driver input voltage or fixed driver displacement. Neither of these measures accurately reflect the efficiency of the actuator. Defining efficiency as "desired output divided by required input," these traditional measures may not account for increase in required driving current or force.

A sharp inside …

A Validation And Comparison About Vabs-Ide And Vabs-Gui, Teng Hu

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Variational Asymptotic Beam Section (VABS) analysis is a computer code for design and analysis of slender structure such as rotor blades, wind turbine blades, missiles, and rockets more efficiently than a full three-dimensional finite element analysis. VABS enables a rigorously a dimensional reduction of the original three-dimensional nonlinear analysis into a one-dimensional nonlinear beam analysis and a two-dimensional linear cross-sectional analysis. The VABS code has been extensively used in academia and industry for comput- ing the sectional properties and recovering three-dimensional fields of composite slender structures. Recently two graphic user interface, namely VABS-IDE and VABS-GUI, have been developed to automatic …

Exploratory Methods For Truck Re-Identification In A Statewide Network Based On Axle Weight And Axle Spacing Data To Enhance Freight Metrics: Phase Ii, Mecit Cetin, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates different methods for solving the re-identification problem and explores some of the factors that impact the accuracy of the results. To support this work, archived data from weigh-in-motion (WIM) stations in Oregon are used for developing, calibrating, and testing vehicle re-identification algorithms. In addition to the Bayesian approach developed by the researchers in the previous study, a neural network model is developed for solving the re-identification problem. The results from the testing …

On-Farm Water Management Game With Heuristic Capabilities, Mohammed Z. Shaban

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Improved on-farm irrigation practices can result in more economical farming, and better productivity. Very little has been done with regard to improved training tools that can be used to promote better and more effective on-farm irrigation practices. Games considered as an effective decision support tools in which players are able to test alternatives, and demonstrate the effects of their decisions, in a short time, and without being afraid of making mistakes. Training tools in the form of games promotes what is called “learning based on experience” through a schematic version of reality, and observing the effects.

The WaterMan game was …

An Investigation Into Delta Wing Vortex Generators As A Means Of Increasing Algae Biofuel Raceway Vertical Mixing Including An Analysis Of The Resulting Turbulence Characteristics, Aaron H. Godfrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current standards of living and future prosperity are closely tied to the availability of sufficient and inexpensive energy resources. Currently society is fueled primarily by some form of fossil fuel. By their very nature these fuel sources are non-renewable, thus our current energy habits are unsustainable. Among the various renewable energy technologies is the capability to produce diesel fuel by colonies of algae. While this technology has many positive features it remains too expensive to be a realistic fuel source. The current work performed analysis using computer simulation of an aquatic environment commonly used to grow algae for the purposes …

Utilizing Correct Prior Probability Calculation To Improve Performance Of Low-Density Parity-Check Codes In The Presence Of Burst Noise, David A. Neal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Error correcting codes help correct errors in transmitted data. These errors are caused by noise and distortion that are introduced during transmission. In some cases, there is more noise on some portions of a transmitted message than on others. This extra noise is referred to as burst noise and causes bursts of errors.

Low-density parity-check (LDPC) codes are a family of error correcting codes. They provide excellent performance in many cases, but perform poorly when burst noise is present. Methods have been developed that help compensate for bursts of errors. In most cases, these do not completely account for the …

Cross Flow Filtration For Mixed-Culture Algae Harvesting For Municipal Wastewater Lagoons, Misheka Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The City of Logan Environmental Department has a goal to remove chemicals from the municipal wastewater that can cause algae growth in Cutler Reservoir that will impair use for recreation. The proposed plan to accomplish the goal is to grow algae within the 460-acre Logan Lagoon wastewater system, and then remove the algae from the treated wastewater that enters Cutler Reservoir. The collected algae may be used to produce biodiesel to fuel the City solid waste vehicles. The City will coordinate the development and implementation of this project with the assistance of the Utah State University Biological Engineering Department. The …

Modeling Spatial Surface Energy Fluxes Of Agricultural And Riparian Vegetation Using Remote Sensing, Hatim M.E. Geli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration (ET) represents the amount of water consumed by vegetation through transpiration plus the direct evaporation from the soil surface. Understanding the amount of ET is important as it represents a portion of fresh water that is consumed and not available for further use. ET is used as indication of how much water needed for agricultural activities. This research is aimed towards providing improved estimates of ET.

The technological advances in remote sensing provide us with images of the Earth’s surface from space, using satellites, and sometimes with more detail from aircraft. We used these data in …

Performance Of Post-Tensioned Curved-Strand Connections In Transverse Joints Of Precast Bridge Decks, Zane B. Wells

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to minimize traffic delays on the nation’s bridges, precast concrete bridge decks have been utilized to quickly and efficiently construct bridges. These precast concrete decks are cast off site and transported to the bridge after they have cured. The decks are then placed onto the bridge and grouted into place. These precast panels have an inherent weakness in that the joints between adjacent panels tend to leak. In order to mitigate leaking of the joints, two adjacent panels are typically post-tensioned together. A variation on the standard post-tensioning in use by some DOT’s was designed and investigated in …

Microencapsulation Of The Non-Steroidal Anti-Inflammatory Drugs Into Biodegradable Polymers Using Supercritical Fluid Technology, Safaa Mohamad Al Mahdi Ali Yousif

Theses

Osteoarthritis is a disease that attacks human bones especially in older people and usually nonsteroidal anti-inflammatory drugs (NSAIDS) are being prescribed for patients with Osteoarthritis. These kinds of drugs usually have low aqueous solubility and in order to have their therapeutic effects, their solubility should be enhanced. The purpose of this study was to find solution for this problem and one way to do that is to reduce the particle size by forming micro particles. In this project, one of these types of drugs ibuprofen (isobutyl-propanoicphenolic Acid) was encapsulated into a polymer (PVP polyvinylpyrrolidone) using supercritical fluid technology (Supercritical CO …

Engineering Design Of A Prototype Ammonia Absorption Tower, Andrew Warren Calogero

Honors Capstones

No abstract provided.

Even Moderate Visual Impairments Degrade Drivers' Ability To See Pedestrians At Night, Joanne M. Wood, Richard A. Tyrell, Alex Chaparro, Ralph P. Marszalek, Trent P. Carberry, Byoung Sun Chu

Publications

PURPOSE. To determine the effect of moderate levels of refractive blur and simulated cataracts on nighttime pedestrian conspicuity in the presence and absence of headlamp glare.

METHODS. The ability to recognize pedestrians at night was measured in 28 young adults (M ¼ 27.6 years) under three visual conditions: normal vision, refractive blur, and simulated cataracts; mean acuity was 20/40 or better in all conditions. Pedestrian recognition distances were recorded while participants drove an instrumented vehicle along a closed road course at night. Pedestrians wore one of three clothing conditions and oncoming headlamps were present for 16 participants and absent for …

Novel Phantoms And Post-Processing For Diffusion Spectrum Imaging, Vaibhav Juneja

Dissertations and Theses (Open Access)

High Angular Resolution Diffusion Imaging (HARDI) techniques, including Diffusion Spectrum Imaging (DSI), have been proposed to resolve crossing and other complex fiber architecture in the human brain white matter. In these methods, directional information of diffusion is inferred from the peaks in the orientation distribution function (ODF). Extensive studies using histology on macaque brain, cat cerebellum, rat hippocampus and optic tracts, and bovine tongue are qualitatively in agreement with the DSI-derived ODFs and tractography. However, there are only two studies in the literature which validated the DSI results using physical phantoms and both these studies were not performed on a …

A Robust Decentralized Load Frequency Controller For Interconnected Power Systems, Lili Dong, Yao Zhang, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

A novel design of a robust decentralized load frequency control (LFC) algorithm is proposed for an inter-connected three-area power system, for the purpose of regulating area control error (ACE) in the presence of system uncertainties and external disturbances. The design is based on the concept of active disturbance rejection control (ADRC). Estimating and mitigating the total effect of various uncertainties in real time, ADRC is particularly effective against a wide range of parameter variations, model uncertainties, and large disturbances. Furthermore, with only two tuning parameters, the controller provides a simple and easy-to-use solution to complex engineering problems in practice. Here, …

Characterization And Optimization Of Solution-Derived Chalcogenide Glass Thin Films, Jacklyn Wilkinson

All Theses

Chalcogenide glasses have many unique properties that allow them to be used in a variety of optical applications. Infrared transparency allows them to be used in sensors for molecules that have 'fingerprints' in the 2-25 μm range. By producing amorphous thin films of these materials, they can be incorporated into chemical sensors as planar waveguides and resonators. The goal of this work was to fabricate and characterize solution-derived chalcogenide thin films for use in chemical sensors with a source wavelength between 3-3.5 μm.
The structural and optical properties of the parent bulk glass were characterized and used as reference for …

Automated Assembly Time Prediction Tool Using Predefined Mates From Cad Assemblies, Joseph Owensby

All Theses

Current Design for Assembly (DFA) methods and tools require extensive amounts and types of user inputs to complete the analysis. Since the methods require extensive amounts and types of inputs, certain issues arise: the analysis can become tedious, time consuming, error prone, and not repeatable. These issues eventually lead to the DFA methods being used as a redesign tool or not being implemented at all.
The research presented in this thesis addresses the current DFA limitations and issues by developing and implementing an automated assembly time prediction tool that: extracts explicitly defined connections from SolidWorks assembly models, determines the structural …

Geology-Based Probabilistic Liquefaction Potential Mapping Of The 7.5-Minute Charleston Quadrangle, South Carolina For Resilient Infrastructure Design, Lawrence Simonson

All Theses

Two geology-based probabilistic liquefaction potential maps are developed for the 7.5-minute Charleston, South Carolina quadrangle in this thesis. Creation of the maps extends the previous liquefaction potential mapping work of the Charleston peninsula by Hayati and Andrus (2008) and Mount Pleasant by Heidari and Andrus (2010), and improves upon the previous maps by using peak ground accelerations that vary with local site conditions. The GIS software package ArcGIS 10 is used to develop the maps.
Development of the liquefaction potential maps involves the creation of four additional maps needed as inputs. The four additional maps are (1) depth to the …

Security And Performance Verification Of Distributed Authentication And Authorization Tools, Seok Bae Yun

All Theses

Parallel distributed systems are widely used for dealing with massive data sets and high performance computing. Securing parallel distributed systems is problematic. Centralized security tools are likely to cause bottlenecks and introduce a single point of failure. In this paper, we introduce existing distributed authentication and authorization tools. We evaluate the quality of the security tools by verifying their security and performance.
For security tool verification, we use process calculus and mathematical modeling languages. Casper, Communicating Sequential Process (CSP) and Failure Divergence Refinement (FDR) to test for security vulnerabilities, Petri nets and Karp Miller trees are used to find performance …

Understanding The Behavior Of A Pile Foundation In Unsaturated Soils Subjected To Lateral Loading, Brian Machmer

All Theses

The purpose of this research was to further understand the behavior of pile foundations in unsaturated soils subjected to lateral loading. Recent case histories show the importance of incorporating unsaturated soil mechanics in geotechnical engineering practice for the design and construction of resilient and cost effective systems. Unsaturated soils are a three phase material- solid, liquid and gas, resulting in three interfaces. Among the three interfaces the liquid-gas interface, also known as the contractile skin, plays a critical role in the mechanical and flow behaviors of unsaturated soil. The effects of the contractile skin are measured in terms of matric …

Entrainment And Dilution Of Constant-Volume Non-Newtonian Fluid Mud Gravity Currents, Michael Jacobson

All Theses

An extensive laboratory experimental campaign was undertaken in order to elucidate the entrainment and dilution characteristics of constant-volume non-Newtonian fluid mud gravity currents. Three experimental series were conducted in a lock-exchange tank. The first experimental series quantified ambient entrainment using a light-opaqueness technique, the second experimental series measured vertical concentration profiles using a siphoning technique, and the third experimental series provided visual observations for the investigation of the deposited sediment layer.
In the first experimental series, a technique similar to the so-called light attenuation technique was developed to find the boundary of the current, allowing for the calculation of entrainment …

Development Of A Lower Extremity Mobility Assessment Methodology For Motor Vehicle Operation And Initial Validation, Justin Arnosky

All Theses

Limited quantifiable data exists on lower extremity mobility and function during driving. To date, the most appropriate existing measures of successful driving function are assessed by a driving rehabilitation specialist during an on-road evaluation. Establishing the kinematic chain- or the order and magnitude in which joints are moved- during driving may prove to be a useful tool in lower extremity function assessment in drivers. To this end, a study was conducted instrumenting both the left and right legs of healthy licensed male drivers (18-26 years old) with a system of angle measuring goniometers (Biometrics, Ltd.) in a driving simulator (DriveSafety …

Set Up Time Reduction And Quality Improvement On The Shop Floor Using Different Lean And Quality Tools, Seetha Ram Bavuluri

All Theses

The purpose of this thesis document is to describe a method developed for reducing setup time in machining processes and simultaneously improve the quality of production after setup. Bosch Rexroth at Fountain Inn is a semi-automated plant and is still in its initial stages of standardizing the setup process. Setup time at different machining centers includes: machining time, inspection time, loading and unloading times and deburring. The focus of the described method is in reducing setup times related to inspection time and loading and unloading times. To achieve success in these problems the following new tools were developed: first piece …

Connected Vehicle Supported Electric Vehicle Charging Operations And Related Infrastructure Issues, Jennifer Johnson

All Theses

Due to the tremendous political, economic and environmental pressures the transportation sector is facing, the United States finds itself devoting more energy to innovative solutions like electric vehicle (EV) technologies. The first objective of this study was to analyze how utilizing real-time information dissemination transferring capabilities to vehicles, as envisioned in the 'connected vehicle' system, could effectively facilitate the EV charging process at fast-charging stations. By simulating a traffic network of EVs in Matlab, it was found that the total time due to the battery charging process could be optimized for EVs that were able to use connected vehicle communications. …

A System-Generated Password And Mnemonic Approach To Optimize The Security And Usability Of Text-Based Passwords, Sanjaykumar Ranganayakulu

All Theses

In this study a novel password generation policy called the system-generated password and mnemonic was designed and implemented. The intent of this policy was to optimize both the security and usability of text-based passwords. After implementing the policy we evaluated its usability and compared it with three other existing policies: user-generated password, system-generated password and user-generated mnemonic for a system-generated password. In order to have a fair comparison among the policies we maintained a constant level of security of 30±2 entropy as dictated by NIST level 2 standards.
The study involved 64 participants, equally divided into four groups, 16 in …

Charging Kinetics Of Micropores In Supercapacitors, Daniel Oberklein

All Theses

The charging kinetics of Electric Double Layer Capacitors (EDLC) were studied using a continuum model based on the Poisson-Nernst-Planck (PNP) Equations, with the additional modeling of the bulk fluid motion in the electrolyte using the Navier-Stokes Equations. The results demonstrate that the addition of bulk flow modeling yields a faster charging rate and higher charging current due to the additional convective component of the current resulting from the bulk fluid motion. A parametric study was conducted to determine the effect of various physical parameters of the EDLC system on the charging kinetics. Decreased fluid viscosity results in a faster charging …