Engineering Commons^™

Characterization Of Radio Frequency Heating Of Fresh Fruits Influenced By Dielectric Properties, Sohan Birla, S. Wang, Juming Tang, G. Tiwari

Biological Systems Engineering: Papers and Publications

Because of its fast and volumetric nature, radio frequency (RF) heating has been looked upon as a way to overcome the problems associated with conventional heating methods used for disinfestation of fruits. But non-uniform heating within fruits is a major obstacle in adaptation of this technology. In this study, RF heating patterns influenced by dielectric properties (DPs) of fruits were investigated both experimentally and mathematically. A computer simulation model was developed using FEMLAB 3.4, a commercial software for solving Maxwell’s electromagnetic and Fourier’s heat transfer equations. Orange, apple, grapefruit, peach, and avocado fruits, selected for these studies were subjected to …

Nutrient Transport As Affected By Rate Of Overland Flow, John E. Gilley, W. F. Sabatka, B. Eghball, David B. Marx

Biological Systems Engineering: Papers and Publications

Little information is currently available concerning the effects of varying flow rate on nutrient transport by overland flow. The objective of this study was to measure the effects of overland flow rate on nutrient transport following the application of beef cattle or swine manure to plots containing 0, 2, 4, or 8 Mg ha^-1 of corn residue. After addition of residue materials to 0.75 m wide by 2.0 m long plots, beef cattle or swine manure was added and the plots were then either disked or maintained in a no-till condition. Three 30 min simulated rainfall events, separated by …

Dynamics Of Adsorbed Pma-D₃ - Effect Of Substrate, Frank D. Blum, Burak Metin, Macduff O. Okuom

Chemistry Faculty Research & Creative Works

In the last few years, our group has focused much of our attention on studying the dynamics of polymers adsorbed at interfaces. Much of our work, to date has been on labeled poly(vinyl acetate)-d3 (PVAc-d3)1 and poly(methyl acrylate)-d3 (PMA-d3)2 on silica. We have been able to probe the effects of adsorbed amount,3 molecular mass,4,5 and the effect of overlayer.6 These studies have provided a view of the adsorbed polymer consistent with a motional gradient in the layer with the more mobile segments being those at the air-polymer interface and the less-mobile segments at the substratepolymer interface. However, we have not …

Dynamics Of Pipa-D₇ On Silica Surface, Piyawan Krisanangkura, Frank D. Blum

Chemistry Faculty Research & Creative Works

Molecular motion of polymer chains is an important determinant in understanding the physical properties of polymeric materials. Glass transition temperature (Tg) is a physical property of polymers, which is of primary interest. The study of the dynamics of polymer segments assists in understanding the dependence of Tg on polymer structure.1 For decades, studies have addressed the molecular motion in various polymers. Some of them have probed the dynamics of polymer backbones.2,3 the properties of a polymer at an interface may change because of the type of polymer, the substrate, or other variables. The side chain of a polymer can also …

Evaluation Of The Effectiveness Of Pavement Rumble Strips, Adam Kirk

Kentucky Transportation Center Research Report

This report analyzes the effectiveness of continuous shoulder rumble strips (CSRS) and center line rumble strips (CLRS) on rural two lane roads in Kentucky. This study evaluates the safety benefits, and design details associated with the application of the CSRS and CLRS. The recommended practices proposed as a result of the crash analysis have the potential to reduce both run off the road and opposite direction crashes on rural two lane roads in Kentucky. These recommendations provide benefits for narrow roadways with little to no shoulder as well as larger roadways with wider paved shoulders.

Deck Replacement - Use Of Extra Coating Thickness Epoxy-Coated Bars, J. A. Ramirez, Rachel Elizabeth Henkhaus

JTRP Technical Reports

The results of this study were implemented in the form of design recommendations for bond of epoxy-coated bars with thicker coatings up to 18 mils. The scope of the work included evaluation of AASHTO LRFD (2004) and ACI 318 design recommendedations for the development and splice length of extra epoxy-coating thinkness reinforcing bars in normal-weight concrete bridge decks and a proposed monitoring plan for a generic concrete bridge deck in Indiana where epoxy-coated bars with thicker coatings might be emeployed. The use of the current provisions for development and splice length of epoxy-coated bars in tension in both the AASHTO …

New Insights Into The Controls And Mechanisms Of Plankton Productivity Along The Us West Coast, Raphael M. Kudela, Neil S. Banas, John A. Barth, Elizabeth R. Frame, David A. Jay, John L. Largier, Evelyn J. Lessard, Tawnya D. Peterson, Andrea J. Vander Woude

Civil and Environmental Engineering Faculty Publications and Presentations

During the lifetime of the National Science Foundation's Coastal Ocean Processes program, four experiments were conducted on the US West Coast in the northern California Current System. Although each project had a unique scientific focus, all four addressed the mechanisms causing eastern boundary current systems in general, and the California Current System in particular, to be biologically rich, from phytoplankton to apex predators. Taken together, findings from these projects provide new insights into the canonical view that upwelling systems are simple wind-driven "conveyor belts," bringing cold, nutrient-rich waters to the well-lit surface ocean where biological organisms flourish. We highlight new …

Suspended Sediment Fluxes At An Intertidal Flat: The Shifting Influence Of Wave, Wind, Tidal, And Freshwater Forcing, Stefan A. Talke, Mark T. Stacey

Civil and Environmental Engineering Faculty Publications and Presentations

Using in situ, continuous, high frequency (8–16 Hz) measurements of velocity, suspended sediment concentration (SSC), and salinity, we investigate the factors affecting near-bed sediment flux during and after a meteorological event (cold front) on an intertidal flat in central San Francisco Bay. Hydrodynamic forcing occurs over many frequency bands including wind wave, ocean swell, seiching (500–1000 s), tidal, and infra-tidal frequencies, and varies greatly over the time scale of hours and days. Sediment fluxes occur primarily due to variations in flow and SSC at three different scales: residual (tidally averaged), tidal, and seiching. During the meteorological event, sediment fluxes are …

The Copula: A Tool For Simulating Speckle Dynamics, Donald D. Duncan, Sean J. Kirkpatrick

Electrical and Computer Engineering Faculty Publications and Presentations

Use of a copula for generating a sequence of correlated speckle patterns is introduced. The chief characteristic of this algorithm is that it generates a continuous speckle sequence with a specified evolution of the correlation and does so with just two arrays of random numbers. Thus, physically realistic temporally varying speckle patterns with proper first- and second-order statistics are easily realized. We illustrate use of the algorithm for generating sequences with prescribed Gaussian, exponential, and equal-interval correlations and demonstrate how correlation times can be specified independently. This approach to generating sequences of random realizations with prescribed correlations should prove useful …

Statistics Of Local Speckle Contrast, Donald D. Duncan, Sean J. Kirkpatrick, Ruikang K. Wang

Electrical and Computer Engineering Faculty Publications and Presentations

In describing the first-order properties of laser speckle under polarized illumination conditions, it is almost an article of faith that the contrast is unity. In many processing schemes, however, the contrast defined as the quotient of the standard deviation and the mean is calculated over a localized spatial region. In such cases, this local contrast displays a distribution of values that can depart substantially from unity. Properties of this distribution depend on details of the data acquisition and on the size of the local neighborhood over which the contrast is calculated. We demonstrate that this local contrast can be characterized …

Can Laser Speckle Flowmetry Be Made A Quantitative Tool?, Donald D. Duncan, Sean J. Kirkpatrick

Electrical and Computer Engineering Faculty Publications and Presentations

The ultimate objective of laser speckle flowmetry (and a host of specific implementations such as laser speckle contrast analysis, LASCA or LSCA; laser speckle spatial contrast analysis, LSSCA; laser speckle temporal contrast analysis, LSTCA; etc.) is to infer flow velocity from the observed speckle contrast. Despite numerous demonstrations over the past 25 years of such a qualitative relationship, no convincing quantitative relationship has been proven. One reason is a persistent mathematical error that has been propagated by a host of workers; another is a misconception about the proper autocorrelation function for ordered flow. Still another hindrance has been uncertainty in …

Monte Carlo Modeling Of Spatial Coherence: Free-Space Diffraction, Donald D. Duncan, David G. Fischer, Scott A. Prahl

Electrical and Computer Engineering Faculty Publications and Presentations

We present a Monte Carlo method for propagating partially coherent fields through complex deterministic optical systems. A Gaussian copula is used to synthesize a random source with an arbitrary spatial coherence function. Physical optics and Monte Carlo predictions of the first- and second-order statistics of the field are shown for coherent and partially coherent sources for free-space propagation, imaging using a binary Fresnel zone plate, and propagation through a limiting aperture. Excellent agreement between the physical optics and Monte Carlo predictions is demonstrated in all cases. Convergence criteria are presented for judging the quality of the Monte Carlo predictions.

Analysis Of Resonating Microcantilevers Operating In A Viscous Liquid Environment, Cyril Vančura, Isabelle Dufour, Stephen M. Heinrich, Fabien Josse, Andreas Hierlemann

Civil and Environmental Engineering Faculty Research and Publications

The characteristics of resonant cantilevers in viscous liquids are analyzed. Various rectangular cantilevers geometries are studied in pure water, glycerol and ethanol solutions of different concentrations, and the results are described in terms of the added displaced liquid mass and the liquid damping force for both, the resonance frequency and the quality factor (Q-factor). Experimental results using a set of magnetically actuated resonant cantilevers vibrating in the out-of-plane (“weak-axis bending”) mode are presented and compared to theoretical calculations. The importance of the study is in the use of resonant cantilevers as biochemical sensors in liquid environments.

Review Of Career Development In Bioengineering And Biotechnology By Guruprasad Madhavan, Barbara Oakley, And Luis Kun (Editors), Springer Science+Business Media, Llc, 2008, Mark R. Riley

Biological Systems Engineering: Papers and Publications

As an educator in biological engineering, I am often asked by students about career opportunities in this growing field. The field of biological engineering merges approaches and methodologies from a variety of traditional disciplines, and so practitioners of biological engineering can find professional opportunities in numerous areas.

The recently published book Career Development in Bioengineering and Biotechnology, (485 pages) edited by Madhavan, Oakley, and Kun, represents an ambitious undertaking with the goal of not only presenting career options and career development techniques but also addressing how the work of an individual can impact society. The book contains 71 chapters divided …

Narrow Grass Hedge Effects On Nutrient Transport Following Compost Application, John E. Gilley, B. Eghball, David B. Marx

Biological Systems Engineering: Papers and Publications

The placement of stiff‐stemmed grass hedges on the contour along a hillslope has been shown to decrease nutrient transport in runoff. This study was conducted to measure the effectiveness of a narrow grass hedge in reducing runoff nutrient transport from plots with a range of soil nutrient values. Composted beef cattle manure was applied at dry weights of 0, 68, 105, 142, and 178 Mg ha^-1 to a silty clay loam soil and then incorporated by disking. Soil samples were collected 243 days later for analysis of water‐soluble phosphorus (WSP), Bray and Kurtz No. 1 phosphorus (Bray‐1 P), NO …

Rule-Based Mamdani-Type Fuzzy Modeling Of Skin Permeability, Deepak R. Keshwani, David D. Jones, George E. Meyer, Rhonda M. Brand

Biological Systems Engineering: Papers and Publications

Two Mamdani type fuzzy models (three inputs–one output and two inputs–one output) were developed to predict the permeability of compounds through human skin. The models were derived from multiple data sources including laboratory data, published data bases, published statistical models, and expert opinion. The inputs to the model include information about the compound (molecular weight and octonal–H₂O partition coefficient) and the application temperature. One model included all three parameters as inputs and the other model only included information about the compound. The values for mole molecular weight ranged from 30 to 600 Da. The values for the log …

Surface Polyethylene Glycol Enhances Substrate-Mediated Gene Delivery By Nonspecifically Immobilized Complexes, Angela K. Pannier, Julie A. Wieland, Lonnie D Shea

Biological Systems Engineering: Papers and Publications

Substrate-mediated gene delivery describes the immobilization of gene therapy vectors to a biomaterial, which enhances gene transfer by exposing adhered cells to elevated DNA concentrations within the local microenvironment. Surface chemistry has been shown to affect transfection by nonspecifically immobilized complexes using self-assembled monolayers (SAMs) of alkanethiols on gold. In this report, SAMs were again used to provide a controlled surface to investigate whether the presence of oligo(ethylene glycol) (EG) groups in a SAM could affect complex morphology and enhance transfection. EG groups were included at percentages that did not affect cell adhesion. Nonspecific complex immobilization to SAMs containing combinations …

Performance Evaluation Of Aluminum Test Cell Designed For Determining The Heat Resistance Of Bacterial Spores In Foods, H.-J. Chung, Sohan Birla, Juming Tang

Biological Systems Engineering: Papers and Publications

Thermal inactivation kinetic studies are necessary to determine heat resistances of spores in the development of new thermal processes for low-acid shelf-stable products. Most currently available sample holders used in the kinetic studies take long time to reach the target sample temperature, hence fail to provide isothermal condition. In this research, novel aluminum test cells were developed to facilitate easy loading and unloading solid and liquid food samples in a hermetically sealed 1 ml cavity to evaluate the heat resistance of bacterial spores when heated at temperatures above 100 °C. Design of the test cell was governed by minimum come-up …

A Survey Of Worm Detection And Containment, Pele Li, M. Salour, Xiao Su

Faculty Publications

Self-duplicating, self-propagating malicious codes known as computer worms spread themselves without any human interaction and launch the most destructive attacks against computer networks. At the same time, being fully automated makes their behavior repetitious and predictable. This article presents a survey and comparison of Internet worm detection and containment schemes. We first identify worm characteristics through their behavior, and then classify worm detection algorithms based on the parameters used in the algorithms. Furthermore, we analyze and compare different detection algorithms with reference to the worm characteristics by identifying the type of worms that can and cannot be detected by these …