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The Benefits Of Automatic Data Collection In The Fresh Produce Supply Chain, Ryan Charles Panos, Tali Freed Sep 2007

The Benefits Of Automatic Data Collection In The Fresh Produce Supply Chain, Ryan Charles Panos, Tali Freed

Industrial and Manufacturing Engineering

The potential for RFID based systems to improve the safety and efficiency of a supply chain with rapidly decaying products and strict health standards is creating pressure to adopt RFID in several agricultural industries. A handful of fresh produce industry leaders currently participate in mandated pilot projects, while the industry as a whole is still intimidated by the perceived cost of RFID. Therefore in this study we attempt to validate the correlation between performance and automated data collection, paving the way to economic justification of investment in data collection technologies, such as barcode and RFID.

The majority of product in …


Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi Sep 2007

Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

This paper presents and implements a framework for modeling the impact of land use practices and protection alternatives on nitrate pollution of groundwater in agricultural watersheds. The framework utilizes the national land cover database (NLCD) of the United State Geological Survey (USGS) grid and a geographic information system (GIS) to account for the spatial distribution of on-ground nitrogen sources and corresponding loadings. The framework employs a soil nitrogen dynamic model to estimate nitrate leaching to groundwater. These estimates were used in developing a groundwater nitrate fate and transport model. The framework considers both point and non-point sources of nitrogen across …


National Livestock And Poultry Environmental Learning Center, Richard K. Koelsch, Mark Risse, Joe Harrison, Jill Heemstra Sep 2007

National Livestock And Poultry Environmental Learning Center, Richard K. Koelsch, Mark Risse, Joe Harrison, Jill Heemstra

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

This paper describes a new national learning center designed to improve the delivery of science-based information to non-research customers. The vision of the Livestock and Poultry Environmental Learning Center is to provide individuals involved in public policy issues, animal production, and delivery of technical services for confined animal systems with on-demand access to the nation’s best science-based resources that is responsive to priority and emerging environmental issues associated with animal agriculture. This project will test innovative approaches such as a web cast seminar series to connect national experts with those individuals and organizations that influence animal producer decisions on manure …


Software Tool For Integrating Feed Management Into Nutrient Planning, Richard K. Koelsch, Ray Massey, Galen E. Erickson, Virgil R. Bremer Sep 2007

Software Tool For Integrating Feed Management Into Nutrient Planning, Richard K. Koelsch, Ray Massey, Galen E. Erickson, Virgil R. Bremer

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

The introduction of ASABE Standard D384.2, Manure Production and Characteristics, has created the opportunity to integrate feed management decisions and animal performance measures into nutrient planning processes. This paper introduces a software tool that integrates estimates of nutrient excretion based on the new standard with estimates of land need, labor and equipment time allocation, and economic cost and benefit for manure application. This tool will be used to evaluate the economic implications for two scenarios using beef cattle examples as a means of illustrating tool application. The first scenario will look at the impact of feeding ethanol co-products on the …


Method And Apparatus For Blood Flow Measurement Using Millimeter Wave Band, David Nelson Sep 2007

Method And Apparatus For Blood Flow Measurement Using Millimeter Wave Band, David Nelson

Michigan Tech Patents

A system and method that determines a blood flow rate in an area of a subject. The system includes a transmitter operable to transmit an electrical signal in the range of about 20 GHz to about 300 GHz to the area, a temperature sensor positioned adjacent the area, and a processor operable to determine the blood flow rate in the area based on the rate of change of temperature in the area as a result of the application of the electrical signal on the area and a power density value.


Measurement Of 'One Over F Noise' In Infrared Detection Using A Novel Technique, Diana Maestas Jepson Sep 2007

Measurement Of 'One Over F Noise' In Infrared Detection Using A Novel Technique, Diana Maestas Jepson

Electrical and Computer Engineering ETDs

It has been shown that, one over f noise' (1/f noise) limits the sensitivity in Mercury Cadmium Telluride (HgCdTe) infrared devices. It is therefore imperative to be able to measure and account for its contribution to the total device noise. In this thesis, the 1/f noise of a HgCdTe device is measured and studied using two measurement techniques. The first technique is the commonly used conventional method of measuring 1/f noise that analyzes 1/f noise in the frequency domain and extracts the 1/f noise contribution from the power spectral densities. The second approach is a novel technique that extracts the …


2007 Engr333/Biol354 Project Assignment, Matthew K. Heun Sep 2007

2007 Engr333/Biol354 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2007 semester ENGR333 project involved a collaboration with students in BIOL354, taught by my colleague Dave Warners. We asked our students “What would it take to make Calvin College carbon neutral?”

This project resulted in the first-ever carbon dioxide emissions and sequestration assessment of Calvin College, attached below.

The student presenters animated the pie charts, and an audible gasp filled the hall when the imbalance between carbon emissions and carbon sequestration became clear.

The students also studied potential routes to carbon neutrality, one of which was a green revolving fund.

This class project resulted in a co-authored publication …


Ufuzzy Prediction Models In Measurement, Leon Reznik, Vladik Kreinovich Sep 2007

Ufuzzy Prediction Models In Measurement, Leon Reznik, Vladik Kreinovich

Departmental Technical Reports (CS)

The paper investigates a feasibility of fuzzy models application in measurement procedures. It considers the problem of measurement information fusion from different sources, when one of the sources provides predictions regarding approximate values of the measured variables or their combinations. Typically this information is given by an expert but may be mined from available data also. This information is formalized as fuzzy prediction models and is used in combination with the measurement results to improve the measurement accuracy. The properties of the modified estimates are studied in comparison with the conventional ones. The conditions when fuzzy models application can achieve …


The Theory Of Planned Behavior As A Model Of Academic Dishonesty In Engineering And Humanities Undergraduates, Trevor S. Harding, Mathew J. Mayhew, Cynthia J. Finelli, Donald D. Carpenter Sep 2007

The Theory Of Planned Behavior As A Model Of Academic Dishonesty In Engineering And Humanities Undergraduates, Trevor S. Harding, Mathew J. Mayhew, Cynthia J. Finelli, Donald D. Carpenter

Materials Engineering

This study examines the use of a modified form of the Theory of Planned Behavior in understanding the decisions of undergraduate students in engineering and humanities to engage in cheating. We surveyed 527 randomly selected students from three academic institutions. Results supported the use of the model in predicting ethical decision-making regarding cheating. In particular, the model demonstrated how certain variables (gender, discipline, high school cheating, education level, international student status, participation in Greek organizations or other clubs) and moral constructs related to intention to cheat, attitudes toward cheating, perceptions of norms with respect to cheating, and ultimately, cheating behaviors. …


Developing A Byproduct Materials Information Systems For The Kentucky Transportation Cabinet, David Q. Hunsucker, Justin Jones, Tom Hopkins, Charlie Sun Sep 2007

Developing A Byproduct Materials Information Systems For The Kentucky Transportation Cabinet, David Q. Hunsucker, Justin Jones, Tom Hopkins, Charlie Sun

Kentucky Transportation Center Research Report

Kentucky has numerous coal-fired, electric generating facilities and, as a result, there are abundant byproduct materials being produced from these facilities that have environmental, engineering, and economic potential as materials for use in common highway construction and maintenance related activities throughout the Commonwealth. Other byproduct materials are being produced and are available that may have potential uses as well. Although large quantities of byproduct materials are produced in Kentucky and many of those materials have positive or neutral environmental impacts and excellent engineering properties, a formal regulatory framework for selecting, characterizing, recovering, and recycling these material types does not exist. …


Robust Tuning Of Modern Power System Stabilizers Using Bacterial Foraging Algorithm, B. Sumanbabu, S. Mishra, B. K. Panigrahi, Ganesh K. Venayagamoorthy Sep 2007

Robust Tuning Of Modern Power System Stabilizers Using Bacterial Foraging Algorithm, B. Sumanbabu, S. Mishra, B. K. Panigrahi, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

IEEE Std 421.5, revised by the IEEE excitation system subcommittee introduced a new type of power system stabilizer model, the multiband power system stabilizers (IEEE PSS4B). Although it requires two input signals, like the widely used IEEE PSS2B, the underlying principle of the new IEEE PSS4B makes it sharply different. This paper presents a method based on Bacterial Foraging Algorithm (BFA) to simultaneously tune these modern power system stabilizers (PSSs) in multimachine power system. Simulation results of multi-machine power system validate the efficiency of this approach. the proposed method is effective for the tuning of multi-controllers in large power systems.


Development And Laboratory Trials Of The Light-Based High-Resolution Target Movement Monitor For Monitoring Convergence At Underground Mines, B. D. Apel, B. R. Gray, Randy Hays Moss, Steve Eugene Watkins, T. H. Jones Sep 2007

Development And Laboratory Trials Of The Light-Based High-Resolution Target Movement Monitor For Monitoring Convergence At Underground Mines, B. D. Apel, B. R. Gray, Randy Hays Moss, Steve Eugene Watkins, T. H. Jones

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a development and laboratory evaluation of the light-based high-resolution target movement monitor which can be used to measure convergence at underground excavations with submillimeter accuracy. The monitor is based on unique measurement technology which was developed at the University of Missouri-Rolla. This system has the potential for high accuracy detection and monitoring of positional changes (as small as 0.1mm with the current laboratory implementation) presented by many types of targets located in close proximity to or at far distances from the monitor. The sensitivity of the system to camera resolution and the error analysis as a function …


Validation Of The Afit Small Scale Combustion Facility And Oh Laser-Induced Fluorescence Of An Atmospheric Laminar Premiext Ed Flame, Stephen J. Koether Sep 2007

Validation Of The Afit Small Scale Combustion Facility And Oh Laser-Induced Fluorescence Of An Atmospheric Laminar Premiext Ed Flame, Stephen J. Koether

Theses and Dissertations

Construction in the AFIT combustion facility is complete and the objective of this report is to explain the steps taken to make the laboratory operational. The infinite radius Ultra-Compact Combustor (UCC) sectional model has been delivered and is fully installed with all fuel, air and instrument lines. Every major system in the lab has been tested and is functioning properly. Laboratory operating procedure has been established to ensure both safety and continuity in experimental results. Finally, the lab has been certified through official safety channels and combustion experiments are underway. The unique capability of the AFIT combustion laboratory is the …


Measurement And Analysis Of The Shocks Generated During Egg Production, Jay A. Singh, Chris Ferrier, Paul Singh Sep 2007

Measurement And Analysis Of The Shocks Generated During Egg Production, Jay A. Singh, Chris Ferrier, Paul Singh

Industrial Technology and Packaging

In their journey from the laying cage to shipments out of an egg production operation, table eggs encounter multiple shock events. While all agricultural commodities run the possibility of damage during the course of production, shell eggs are particularly susceptible to being cracked or broken during the production operation. A typical egg production facility experiences 2% to 7% checks (a partial mechanical failure to the egg shell) during handling, packaging and transportation of shell eggs. It has been estimated that the total losses to the U.S. egg industry due to checks and breakage of eggs during production amounts to over …


Urban Particulate Matter Casues Er Stress And The Unfolded Protein Response In Human Lung Cells, T. L. Watterson, B. Hamilton, Randy S. Martin, R. A. Coulombe Jr. Sep 2007

Urban Particulate Matter Casues Er Stress And The Unfolded Protein Response In Human Lung Cells, T. L. Watterson, B. Hamilton, Randy S. Martin, R. A. Coulombe Jr.

Civil and Environmental Engineering Faculty Publications

Because of its presumed adverse health effects, particulate air pollution (PM) has received growing attention, but the cellular mechanisms by which PM exerts toxicity are not well elucidated. PM has been associated with early mortality from illnesses that share endoplasmic reticulum (ER) stress as a mechanism of pathogenesis. In this study, we examined whether PM would induce the unfolded protein response (UPR) which is a cellular response to ER stress. Coarse (PM10) and fine (PM2.5) PM was collected from a single location in Northern Utah's Cache Valley during atmospheric inversions occurring in January 2002 and January 2003. Extracts of PM …


Effects Of Pm2.5 Collected From Cache Valley, Ut On Genes Associated With The Inflammatory Response In Human Lung Cells, T L. Watterson, J. Sorensen, Randy S. Martin, R. A. Coulombe Jr. Sep 2007

Effects Of Pm2.5 Collected From Cache Valley, Ut On Genes Associated With The Inflammatory Response In Human Lung Cells, T L. Watterson, J. Sorensen, Randy S. Martin, R. A. Coulombe Jr.

Civil and Environmental Engineering Faculty Publications

In January 2004, the normally picturesque Cache Valley in northern Utah made national headlines with the highest PM2.5 levels in the nation. Epidemiological studies linked exposure to particulate air pollution in other locations with stroke and Alzheimer's disease and to early mortality from all causes, cancer, and cardiopulmonary diseases. To determine potential effects of these particles on human health, human bronchial epithelial cells (BEAS-2B) were cultured with PM2.5collected from various locations in the Cache Valley. These particles were slightly cytotoxic, but more potent than NH4NO3, the major chemical component of Cache Valley PM2.5. Gene expression analysis of PM2.5-exposed cells was …


Role Of Mitochondrial Electron Transport Complex I In Coenzyme Q1 Reduction By Intact Pulmonary Arterial Endothelial Cells And The Effect Of Hyperoxia, Marilyn P. Merker, Said H. Audi, Brian J. Lindemer, Gary S. Krenz, Robert D. Bongard Sep 2007

Role Of Mitochondrial Electron Transport Complex I In Coenzyme Q1 Reduction By Intact Pulmonary Arterial Endothelial Cells And The Effect Of Hyperoxia, Marilyn P. Merker, Said H. Audi, Brian J. Lindemer, Gary S. Krenz, Robert D. Bongard

Biomedical Engineering Faculty Research and Publications

The objective was to determine the impact of intact normoxic and hyperoxia-exposed (95% O(2) for 48 h) bovine pulmonary arterial endothelial cells in culture on the redox status of the coenzyme Q(10) homolog coenzyme Q(1) (CoQ(1)). When CoQ(1) (50 microM) was incubated with the cells for 30 min, its concentration in the medium decreased over time, reaching a lower level for normoxic than hyperoxia-exposed cells. The decreases in CoQ(1) concentration were associated with generation of CoQ(1) hydroquinone (CoQ(1)H(2)), wherein 3.4 times more CoQ(1)H(2) was produced in the normoxic than hyperoxia-exposed cell medium (8.2 +/- 0.3 and 2.4 +/- 0.4 microM, …


Bs News Sep 2007

Bs News

Building Services Engineering

No abstract provided.


Fluvial Geomorphologic And Hydrodynamic Assessment In The Tidal Portion Of The Lower Rio Grande River, Us-Mexico Borderland, Andrew Ernest, B. Bokhim, N. B. Chang, I. J. Huang Sep 2007

Fluvial Geomorphologic And Hydrodynamic Assessment In The Tidal Portion Of The Lower Rio Grande River, Us-Mexico Borderland, Andrew Ernest, B. Bokhim, N. B. Chang, I. J. Huang

Civil Engineering Faculty Publications

With fast population growth and economic development in the US-Mexico Borderland, water diversion and usages has reduced the flow substantially in the Low Rio Grande River (LRGR). Tidal portion of the LRGR has posed an environmental drought issue since 1993 and the channel clogged with the invasion of non-native plants also causes environmental problems. As a result of the intensity of these natural and manmade factors, the Rio Grande stopped flowing to the sea in February 2001. The flows were reduced to a point that they were unable to push out the sand deposited at the mouth. Geomorphologic evolution in …


Assessment Of The Bill Emerson Memorial Cable-Stayed Bridge Based On Seismic Instrumentation Data, Genda Chen, Dongming Yan, Wenjian Wang, Man Zheng, Louis Ge, Frank Liu Sep 2007

Assessment Of The Bill Emerson Memorial Cable-Stayed Bridge Based On Seismic Instrumentation Data, Genda Chen, Dongming Yan, Wenjian Wang, Man Zheng, Louis Ge, Frank Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, both ambient and earthquake data measured from the Bill Emerson Memorial Cable-stayed Bridge are reported and analyzed. Based on the seismic instrumentation data, the vibration characteristics of the bridge are investigated and used to validate a three-dimensional Finite Element (3-D FE) model of the bridge structure. The 3-D model is rigorous and comprehensive, representing realistic dynamic behaviors of the bridge. It takes into account the geometric nonlinear properties caused by cable sagging and soil-foundation-structure interaction in the Illinois approach of the bridge. The FE model is successfully verified and validated by using the natural frequencies and mode …


Self-Healing Control With Multifunctional Gate Drive Circuits For Power Converters, Peng Xiao, Ganesh K. Venayagamoorthy, Keith Corzine, Robert S. Woodley Sep 2007

Self-Healing Control With Multifunctional Gate Drive Circuits For Power Converters, Peng Xiao, Ganesh K. Venayagamoorthy, Keith Corzine, Robert S. Woodley

Electrical and Computer Engineering Faculty Research & Creative Works

Many commercial and military transport systems have fault diagnostic functions implemented to help protect the device when a severe fault occurs. However, most present systems do not contain prognostics capability which would allow operators to observe an unhealthy system component in its pre- fault condition. In industry applications, scheduled downtime can result in considerable cost avoidance. The next technology step is self-healing system components which observe not only potential problems, but can also take steps to continue operation under abnormal conditions - whether due to long-term normal wear-and-tear or sudden combat damage. In this paper, current and voltage information using …


Defect-Tolerant Gate Macro Mapping & Placement In Clock-Free Nanowire Crossbar Architecture, Ravi Bonam, Yong-Bin Kim, Minsu Choi Sep 2007

Defect-Tolerant Gate Macro Mapping & Placement In Clock-Free Nanowire Crossbar Architecture, Ravi Bonam, Yong-Bin Kim, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

Recently, we proposed a new clock-free nanowire crossbar architecture based on a delayinsensitive paradigm called Null Convention Logic (NCL). The proposed architecture has simple periodic structure that is suitable for non-deterministic nanoscale assembly and does not require a clock distribution network - so it is intrinsically free from timing-related failure modes. Even though the proposed architecture offers improved manufacturability, it is still not free from defects. This paper elaborates on the different programming techniques to map a given threshold gate macro on a random PGMB (Programmable Gate Macro Block) with predefined dimension. Defect-Aware and Defect Unaware approaches have been considered …


Finite Element Analysis Of Lamb Waves Acting Within A Thin Aluminum Plate, Sejin Han Sep 2007

Finite Element Analysis Of Lamb Waves Acting Within A Thin Aluminum Plate, Sejin Han

Theses and Dissertations

Structural health monitoring (SHM) is an emerging technology that can be used to identify, locate and quantify structural damages before failure. Among SHM techniques, Lamb waves have become widely used since they can cover large areas from one single location. Due to the development of various structural simulation programs, there is increasing interest in whether SHM data obtained from the simulation can be verified by experimentation. The objective of this thesis is to determine Lamb wave responses using SHM models in ABAQUS CAE(a Finite Element Analysis(FEA) program). These results are then compared to experimental results and theoretical predictions under isothermal …


Receiver Operating Characteristic And Location Analysis Of Simulated Near-Infrared Tomography Images, Xiaomei Song, Brian W. Pogue, Hamid Dehghani, Shudong Jiang, Keith D. Paulsen, Tor D. Tosteson Sep 2007

Receiver Operating Characteristic And Location Analysis Of Simulated Near-Infrared Tomography Images, Xiaomei Song, Brian W. Pogue, Hamid Dehghani, Shudong Jiang, Keith D. Paulsen, Tor D. Tosteson

Dartmouth Scholarship

Receiver operating characteristic (ROC) analysis was performed on simulated near-infrared tomography images, using both human observer and contrast-to-noise ratio (CNR) computational assessment, for application in breast cancer imaging. In the analysis, a nonparametric approach was applied for estimating the ROC curves. Human observer detection of objects had superior capability to localize the presence of heterogeneities when the objects were small with high contrast, with a minimum detectable threshold of CNR near 3.0 to 3.3 in the images. Human observers were able to detect heterogeneities in the images below a size limit of 4 mm, yet could not accurately find the …


Transportation Fuel Research And Development: Statistically Validated Codes And Standards, Fatih Dogan Aug 2007

Transportation Fuel Research And Development: Statistically Validated Codes And Standards, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The recent establishment of the National University Transportation Center at MST under the "Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users," expands the research and education activities to include alternative transportation fuels and other issues that are at the forefront of society and the national agenda. UMR in partnership with MTI will establish a rural hydrogen transportation test bed for developing, demonstrating, evaluating, and promoting hydrogen-based technologies in a real-world environment. The State of Missouri is ideally suited to develop and demonstrate the proper operation of hydrogen highways in a rural setting, which represents over 25 percent …


Steer It And Clear It: Effectiveness Of Quick Clearance Legislation, Amy Carol Hamlin Aug 2007

Steer It And Clear It: Effectiveness Of Quick Clearance Legislation, Amy Carol Hamlin

All Theses

Innovative incident management strategies have been sought by transportation professionals to minimize the impacts of incidents on traffic operation and safety. Some current quick clearance strategies such as 'Steer It and Clear It' legislation in South Carolina, which requires driver(s) of involved vehicle(s) in a minor incident to move vehicles promptly from the traveled roadway prior to the arrival of the first responders, can potentially reduce the duration of an incident. The research detailed in this paper endeavored to measure the benefit of the Steer It and Clear It law on a section of I-85 in South Carolina. A simulation …


Achiral And Chiral Analysis Of Polychlorinated Biphenyls (Pcbs) In The Aquatic And Riparian Food Webs In Twelve Mile Creek, South Carolina., Viet Dang Aug 2007

Achiral And Chiral Analysis Of Polychlorinated Biphenyls (Pcbs) In The Aquatic And Riparian Food Webs In Twelve Mile Creek, South Carolina., Viet Dang

All Theses

Polychlorinated biphenyls (PCBs) contamination in the Twelve Mile Creek arm of Lake Hartwell, South Carolina, has been an issue for decades. Lake Hartwell, which is a reservoir located on the border between the states of South Carolina and Georgia, was contaminated with an estimated 440,000 pounds of PCBs. PCBs were released from the Sangamo-Weston capacitor plant located on Town Creek, which feeds into Twelve Mile Creek and ultimately Lake Hartwell. The Twelve Mile Creek tributary connecting the Sangamo-Weston plant to Lake Hartwell has had little attention. Understanding PCBs contamination in the aquatic and riparian food webs of Twelve Mile Creek …


Estimating Business And Residential Water Supply Interruption Losses From Catastrophic Events, Nicholas Brozovic, David L. Sunding, David Zilberman Aug 2007

Estimating Business And Residential Water Supply Interruption Losses From Catastrophic Events, Nicholas Brozovic, David L. Sunding, David Zilberman

Daugherty Water for Food Global Institute: Faculty Publications

Following man-made or natural catastrophes, widespread and long-lasting disruption of lifelines can lead to economic impacts for both business and residential lifeline users. As a result, the total economic losses caused by infrastructure damage may be much higher than the value of damage to infrastructure itself. In this paper, we consider the estimation of economic impacts on businesses and residential consumers resulting from water supply disruption. The methodology we present for estimating business interruption losses assumes that marginal losses are increasing in the severity of disruption and that there may be a critical water availability cutoff below which business activity …


Effects Of Aggregates On Properties And Performance Of Mastics And Superpave Hot Mix Asphalt Mixtures, Francisco Aragão Aug 2007

Effects Of Aggregates On Properties And Performance Of Mastics And Superpave Hot Mix Asphalt Mixtures, Francisco Aragão

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Superpave, a set of advancements in testing devices and specifications for asphalt binders and mixtures, was limited to address the effects of aggregates. Because aggregates represent around 95% in mass of the asphalt mixtures, it is important to understand how these materials affect properties and performance of such mixtures. This research focus on how different types and contents of aggregates affect properties of mastics and asphalt mixtures, and their performance considering the viscoelastic nature of the asphalt material.

Five different types of aggregates and hydrated lime were used for sample fabrication together with two different binders. Several different tests were …


Particle Shape As Revealed By Spectral Depolarization, Donald D. Duncan, Michael Eugene Thomas Aug 2007

Particle Shape As Revealed By Spectral Depolarization, Donald D. Duncan, Michael Eugene Thomas

Electrical and Computer Engineering Faculty Publications and Presentations

Through a series of numerical simulations we explore some scatter effects due to nonspherical particles. Specifically, we examine the link between the aspect ratio of randomly oriented, prolate spheroidal particles and the resulting linear depolarization of the scattered light in the forward and backscatter directions. The particular objective is to detect the presence of randomly oriented particles that have a systematic size and aspect ratio. Calculations show that the spectral behavior of the linear depolarization reveals the aspect ratio of the scattering particles. The concept is demonstrated using the size, shape, and refractive index of the spore form of Bacillus …