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2008

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Articles 2011 - 2040 of 4190

Full-Text Articles in Engineering

Mathematical Modeling Of Oral Cavity Mucositis, Jason White May 2008

Mathematical Modeling Of Oral Cavity Mucositis, Jason White

Honors Scholar Theses

Oral Mucositis is a condition seen in post-treatment mouth cancer patients and is a condition of which the pathobiology is not entirely known. It is a condition that shares many common pathways with other alimentary tract injuries such as inflammatory bowel disease. Mathematical modeling of the system can help to identify gaps in the current knowledge base as well as assist in generating new hypotheses and predicting clinical outcomes of conditions. A detailed mathematical model would assist researchers in determining which drug targets are worthwhile investigating. Deterministic modeling and Virtual Cell&#; software were used to assign rate constants to each …


Bs News May 2008

Bs News

Building Services Engineering

No abstract provided.


Effect Of Shear On Performance And Microbial Ecology Of Continuously Stirred Anaerobic Digesters Treating Animal Manure, Rebecca A. Hoffmann, Marcelo L. Garcia, Mehul Veskivar, Khursheed Karim, Muthanna H. Al-Dahhan, Largus T. Angenent May 2008

Effect Of Shear On Performance And Microbial Ecology Of Continuously Stirred Anaerobic Digesters Treating Animal Manure, Rebecca A. Hoffmann, Marcelo L. Garcia, Mehul Veskivar, Khursheed Karim, Muthanna H. Al-Dahhan, Largus T. Angenent

Chemical and Biochemical Engineering Faculty Research & Creative Works

We Determined the Effect of Different Mixing Intensities on the Performance, Methanogenic Population Dynamics, and Juxtaposition of Syntrophic Microbes in Anaerobic Digesters Treating Cow Manure from a Dairy Farm. Computer Automated Radioactive Particle Tracking in Conjunction with Computational Fluid Dynamics Was Performed to Quantify the Shear Levels Locally. Four Continuously Stirred Anaerobic Digesters Were Operated at Different Mixing Intensities of 1,500, 500, 250, and 50 Revolutions Per Min (RPM) over a 260-Day Period at a Temperature of 34 ± 1°C. Animal Manure at a Volatile Solids (VS) Concentration of 50 G/L Was Fed into the Digesters Daily at Five Different …


Novel Wideband Directional Dipole Antenna On A Mushroom Like Ebg Structure, Mohammed Z. Azad, Mohammod Ali May 2008

Novel Wideband Directional Dipole Antenna On A Mushroom Like Ebg Structure, Mohammed Z. Azad, Mohammod Ali

Faculty Publications

A new method to design thin wideband directional dipole antennas on electromagnetic bandgap (EBG) structure is introduced. At the heart of this method is the idea to understand and properly utilize the complex interactions between the dipole impedance and the EBG reflection phase characteristics. Using the proposed technique a thin wideband printed dipole is designed, fabricated and tested. The antenna can satisfy applications, such as Digital Communication System (DCS, 1.71-1.88 GHz), Global System for Mobile Communication (GSM, 1.85-1.99 GHz), Personal Communication System (PCS, 1.85-2.05 GHz), Universal Mobile Telecommunication System (UMTS, 1.92-2.17 GHz) and Wireless Local area Network (WLAN, 2.4-2.485 GHz) …


Spectrally Shaped Generalized Mc-Ds-Cdma With Dual Band Combining For Increased Diversity, Wenhui Xiong, David W. Matolak May 2008

Spectrally Shaped Generalized Mc-Ds-Cdma With Dual Band Combining For Increased Diversity, Wenhui Xiong, David W. Matolak

Faculty Publications

A new multicarrier spread spectrum modulation scheme is proposed in this paper. This scheme uses sinusoidal chip waveforms to shape the spectrum of each subcarrier of a multicarrier direct sequence spread spectrum (DS-SS) signal. As a result, each subcarrier has two distinct spectral lobes, one a lower sideband (LSB) and the other an upper sideband (USB). By properly selecting the parameters of the sinusoidal chip waveforms, the two sideband signals can be made to undergo independent fading in a dispersive fading channel. These two independently-faded sideband signals, when combined at the receiver, provide diversity gain to the system. Our analysis …


Artificial Neural Network Estimation Of Soil Erosion And Nutrient Concentrations In Runoff From Land Application Areas, Minyoung Kim, John E. Gilley May 2008

Artificial Neural Network Estimation Of Soil Erosion And Nutrient Concentrations In Runoff From Land Application Areas, Minyoung Kim, John E. Gilley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The transport of sediment and nutrients from land application areas is an environmental concern. New methods are needed for estimating soil and nutrient concentrations of runoff from cropland areas on which manure is applied. Artificial Neural Networks (ANNs) trained with a backpropagation (BP) algorithm were used to estimate soil erosion, dissolved P (DP) and NH4–N concentrations of runoff from a land application site near Lincoln, Nebraska, USA. Simulation results from ANN-derived models showed that the amount of soil eroded is positively correlated with rainfall and runoff. In addition, concentrations of DP and NH4–N in overland flow …


Cellular Arrays (Us Patent Application), Angela K. Pannier, Eric A. Ariazi, V. Craig Jordan, Lonnie D. Shea May 2008

Cellular Arrays (Us Patent Application), Angela K. Pannier, Eric A. Ariazi, V. Craig Jordan, Lonnie D. Shea

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present invention relates to characterizing transcription within cells. In particular, the present invention provides transfected cell arrays (e.g., two-dimensional and/or three-dimensional arrays) and systems, kits and methods utilizing the same (e.g., for transcriptional activity characterization). Compositions and methods of the present invention find use in, among other things, research, drug discovery and clinical (e.g., diagnostic, preventative and therapeutic) applications.


Narrow Grass Hedge Effects On Nutrient Transport Following Compost Application, John E. Gilley, Bahman Eghball, David B. Marx May 2008

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

Department of Agricultural and Biological Systems Engineering: Faculty 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 …


Hydrologic Remote Sensing And Land Surface Data Assimilation, Hamid Moradkhani May 2008

Hydrologic Remote Sensing And Land Surface Data Assimilation, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Accurate, reliable and skillful forecasting of key environmental variables such as soil moisture and snow are of paramount importance due to their strong influence on many water resources applications including flood control, agricultural production and effective water resources management which collectively control the behavior of the climate system. Soil moisture is a key state variable in land surface?atmosphere interactions affecting surface energy fluxes, runoff and the radiation balance. Snow processes also have a large influence on land-atmosphere energy exchanges due to snow high albedo, low thermal conductivity and considerable spatial and temporal variability resulting in the dramatic change on surface …


An Iterative Route Construction And Improvement Algorithm For The Vehicle Routing Problem With Soft And Hard Time Windows, Miguel A. Figliozzi May 2008

An Iterative Route Construction And Improvement Algorithm For The Vehicle Routing Problem With Soft And Hard Time Windows, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

The joint solution of routing problems with soft and hard time windows has valuable practical applications. Simultaneous solution approaches to both types of problems are needed when: (a) the number of routes needed for hard time windows exceeds the number of available vehicles, (b) a study of cost-service tradeoffs is required or the dispatcher has qualitative information regarding the relative importance of hard time window constraints across customers. A new Iterative Route Construction and Improvement (IRCI) algorithm of average run time performance O(n2 ) is proposed to sequentially solve Vehicle Routing Problems with Soft Time Windows (VRPSTW) and Hard Time …


Seepage Evaluations In Cache Valley Irrigation Canals, Katerine N. Molina May 2008

Seepage Evaluations In Cache Valley Irrigation Canals, Katerine N. Molina

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Estimation of seepage was done in 39 selected reaches of 11 irrigation canals in the Logan and Blacksmith Fork Irrigation Systems of Cache Valley, Utah. The measurements were performed from June to October, 2008, which includes part of the irrigation season for these canals. The inflow-outflow method was used to measure seepage, in which area and velocities were measured under steady flow conditions. Velocity measurements were done with an acoustic flow meter and the mean velocity was determined using the reduced-point method (velocity measurements at 0.2, 0.6 and or 0.8 of the depth from the water surface).

As a result, …


A Ladar-Based Pose Estimation Algorithm For Determining Relative Motion Of A Spacecraft For Autonomous Rendezvous And Dock, Ronald Christopher Fenton May 2008

A Ladar-Based Pose Estimation Algorithm For Determining Relative Motion Of A Spacecraft For Autonomous Rendezvous And Dock, Ronald Christopher Fenton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Future autonomous space missions will require autonomous rendezvous and docking operations. The servicing spacecraft must be able to determine the relative 6 degree-of-freedom (6 DOF) motion between the vehicle and the target spacecraft. One method to determine the relative 6 DOF position and attitude is with 3D ladar imaging. Ladar sensor systems can capture close-proximity range images of the target spacecraft, producing 3D point cloud data sets. These sequentially collected point-cloud data sets were then registered with one another using a point correspondence-less variant of the Iterative Closest Points (ICP) algorithm to determine the relative 6 DOF displacements. Simulation experiments …


Micro Air Vehicle (Mav): Numerical Optimization Of A Coaxial Rotor Blade Design, Jeffrey A. Kornuta May 2008

Micro Air Vehicle (Mav): Numerical Optimization Of A Coaxial Rotor Blade Design, Jeffrey A. Kornuta

Honors Capstones

No abstract provided.


A Two-Degree-Of-Freedom Time-Optimal Solution For Hard Disk Drive Servo Problems, Shaohua Hu, Zhiqiang Gao May 2008

A Two-Degree-Of-Freedom Time-Optimal Solution For Hard Disk Drive Servo Problems, Shaohua Hu, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

This paper deals with the hard disk drive (HDD) servo problems. A novel discrete time-optimal control solution is proposed in a two-degree-of-freedom (2DOF) structure, employing both the feedback and feedforward controllers. The time-optimal feedback controller, derived from a simple, double integral plant model, shows remarkable robustness and disturbance rejection in the presence of resonant modes, measurement noises and position and torque disturbances. It eliminates the needs for two separate controllers for track-seeking and track-following operations. The proposed feedforward controller in this 2DOF structure proves to be quite beneficial in reducing the …


Investigating The Role Of Prototyping In Mechanical Design Using Case Study Validation, David Stowe May 2008

Investigating The Role Of Prototyping In Mechanical Design Using Case Study Validation, David Stowe

All Theses

The purpose of this research is to explore the application of prototyping in the design process through a case study analysis using structured interviews, an ethnographic study, and documents analysis, to determine what factors and practices result in successful prototyping. In doing so, research questions are established, a prototyping process is developed to assist the investigation, and classification systems are created to organize data collected in the study. As part of the case study, an interview is formulated to answer the proposed research questions and a literature survey of prototyping in design is used to create a larger analytical foundation. …


Synthesis And Dielectric Properties Of Nanocrystalline Barium Titanate And Silver/Barium Titanate Particles, Hiroki Maie May 2008

Synthesis And Dielectric Properties Of Nanocrystalline Barium Titanate And Silver/Barium Titanate Particles, Hiroki Maie

All Theses

The increasing needs for further functionality, higher performance, and miniaturization of electronic devices have highly demanded down-size and volume-efficiency of electronic components such as multilayer ceramic capacitors (MLCCs). To meet this demand, the use of high dielectric constant material with nanometer size and spherical shape is considered as requirements. Embedded capacitors are an important emerging technology for meeting the performance and functionality requirements of next-generation electronic devices. One major obstacle for implementing this technology is the scarcity of dielectric materials with appropriate dielectric and mechanical properties was mainly discussed

Considering these backgrounds, this research is devoted to synthesis of high …


Factors Affecting The Performance Of Brick Veneer Construction, Jocelyn Dickie May 2008

Factors Affecting The Performance Of Brick Veneer Construction, Jocelyn Dickie

All Theses

The first topic focused on in this report is the height restriction imposed by the masonry standard for brick veneer on wood frame backing. The current US standard (ACI 530-05/ASCE 5-05/TMS 402-05 Building Code Requirements for Masonry Structures) does not allow brick veneer to extend more than thirty feet above the foundation when supported by wood framing. These prescriptive requirements are compared with those of the Canadian (CSA 304.1-04) and Australian (AS 3700-2001) masonry standards. The logic found for this height restriction is based on the vertical differential movement caused by moisture and thermal expansion of the brick veneer and …


Improved Closed-Form Bounds On The Performance Of Convolutional Codes With Correlated Rayleigh Fading, Dwight Hutchenson May 2008

Improved Closed-Form Bounds On The Performance Of Convolutional Codes With Correlated Rayleigh Fading, Dwight Hutchenson

All Theses

New bounds on the probability of bit error are presented for a coded communication system with binary antipodal modulation and soft-decision maximum-likelihood decoding over a correlated Rayleigh-fading channel. The bounds are closed-form expressions in terms of the code's transfer function; they are illustrated by considering a system using convolutional encoding. A long-standing conjecture regarding the worst-case error event in correlated Rician fading is proven for the special case of correlated Rayleigh fading, and it is used in the development of some of the new bounds. The bounds are shown to be tighter than previously developed closed-form bounds for communications using …


Surface Functionalized Colloidal Particles And Polymer Synthesis For Led Based Applications, Zachary Hunt May 2008

Surface Functionalized Colloidal Particles And Polymer Synthesis For Led Based Applications, Zachary Hunt

All Theses

Over the last decade atom transfer radical polymerization, ATRP, has become a commonplace route by which tailored polymers can be synthesized. The advent of this polymerization mechanism has enabled the controlled synthesis of block and multi-block polymer systems that maintain a terminal bromine functionality that adds further versatility to the synthesized polymers.
Additionally, in the last few years 'click' chemistry has come to light as an efficient method of selectively linking molecules under mild conditions (e.g. room temperature and aqueous systems). In particular, the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has become more and more popular, and provides another route by …


The Awe Wall: A Novel Robotic Surface, Martha Kwoka May 2008

The Awe Wall: A Novel Robotic Surface, Martha Kwoka

All Theses

In this thesis, we present fundamental contributions towards AWE, a novel 'Animated Work Environment', which seeks to introduce robotics at the architectural scale to modify environments in real time to the changing needs and moods of their occupants. Part of AWE is a robotic surface, or wall, featuring a multiple folding panel structure. The panels of the AWE wall feature embedded IT and adapt to the current movements and tasks of the user. We describe the overall AWE concept and discuss the construction of the robot surface, its motion planning and its control, and all experiments run to this point.


On New Applications And Sensitivity Enhancement Of Cantilever-Based Sensing Systems, Calvin Bradley May 2008

On New Applications And Sensitivity Enhancement Of Cantilever-Based Sensing Systems, Calvin Bradley

All Theses

Cantilever-based Sensing Systems (CSS) have become a focal area for research with the rise of micro- and nanotechnology. History has led us to use cantilever beams as one of the foremost sensing devices for small scale applications, beginning with the atomic force microscopy, and then being expanded into numerous sensor devices. The CSS include such applications as accelerometers, thermal and chemical sensors which are expanding into the applications of mass sensing and material characterization. Soon, this technology may be used in 'lab on chip' biosensing applications.
This study covers the experimentation into new CSS applications and sensitivity enhancement. In order …


The Formation Of Halonitromethanes In Wastewater Treatment Plant Effluents, Jesse Addison May 2008

The Formation Of Halonitromethanes In Wastewater Treatment Plant Effluents, Jesse Addison

All Theses

Disinfection by-products (DBPs) have been a water treatment concern since their discovery in the 1970's. Today, only eleven drinking water DBPs are regulated by the Environmental Protection Agency (EPA). However, over 500 DBPs have been identified in drinking waters with advances in analytical methods within the last two decades. Halonitromethanes (HNMs) were among the fifty-plus unregulated high-priority DBPs that were monitored for and detected in drinking waters in a recent nationwide occurrence study funded by EPA. The toxicology studies conducted in recent years showed that HNMs are one of the most cytotoxic and genotoxic classes among the emerging DBPs, and …


A Systems Approach To The Design Of A Two Dimensional Cell Printer, Albert Hill May 2008

A Systems Approach To The Design Of A Two Dimensional Cell Printer, Albert Hill

All Theses

Tissue engineering research has the potential to improve the current opportunities for replacement organs and tissues. Precise placement of cells has proven difficult in the early stages of this research. Bioprinting is an important research area that has the potential to accurately position cells and biological materials for tissue engineering. This paper describes the attempt to obtain micrometer accuracy in the placement of cells using a systems approach and technology derived from the Hewlett Packard 500 series of printers and their cartridges the HP26 series. The paper discusses the research and design of a custom printing system that allows control …


Modeling Of The Effect Of Tool Wear On Cutting Forces In Turning, Yu Long May 2008

Modeling Of The Effect Of Tool Wear On Cutting Forces In Turning, Yu Long

All Dissertations

Machining is the most widely used and efficient material removal process, and tool wear in machining is usually of great interest in order to improve machining efficiency and effectiveness. Cutting tool wear patterns such as the flank and crater wear and the dead metal zone (DMZ) may induce the cutting tool geometry variation in machining. As a result, cutting forces may increase or decrease due to the change of tool effective cutting geometry during machining operations. A quantitative understanding of and the ability to predict cutting forces in relation to tool wear are important to the tool life estimation, chatter …


Physics-Based Shape Morphing And Packing For Layout Design, Hong Dong May 2008

Physics-Based Shape Morphing And Packing For Layout Design, Hong Dong

All Dissertations

The packing problem, also named layout design, has found wide applications in the mechanical engineering field. In most cases, the shapes of the objects do not change during the packing process. However, in some applications such as vehicle layout design, shape morphing may be required for some specific components (such as water and fuel reservoirs). The challenge is to fit a component of sufficient size in the available space in a crowded environment (such as the vehicle under-hood) while optimizing the overall performance objectives of the vehicle and improving design efficiency. This work is focused on incorporating component shape design …


Development Of Prediction Models Of High Temperature Crumb Rubber Modified Binders, Carl Thodesen May 2008

Development Of Prediction Models Of High Temperature Crumb Rubber Modified Binders, Carl Thodesen

All Dissertations

The purpose of this research was to identify and model critical elements of the asphalt rubber matrix contributing to the crumb rubber modified (CRM) binder properties as measured by Superpave testing procedures. Current models are neither applicable (due to new testing procedures) nor practical (due to the difficulty of application or lack of accuracy). Therefore, this research investigated the development of predictive models for estimating binder properties within a specified range of accuracy.
Multiple crumb rubber sources were evaluated in order to gain an understanding of the differences between the various crumb rubbers. This analysis permitted identification of the important …


Effects Of Warm Asphalt Additives On Asphalt Binder And Mixture Properties, Tejash Gandhi May 2008

Effects Of Warm Asphalt Additives On Asphalt Binder And Mixture Properties, Tejash Gandhi

All Dissertations

With increasing concerns of global warming and increasing emissions, the asphalt industry is making a constant effort to lower its emissions by reducing the mixing and compaction temperatures of the asphalt mixture without affecting the properties of the mix. Several proprietary chemicals are available in the industry that can help reduce the mixing and compaction temperatures. A significant reduction of required heat can be achieved in most cases. While some studies have been conducted to evaluate the properties of warm mix asphalt; properties of binders and mixtures, in fresh and aged conditions, containing these chemicals have not been studied in …


Vibration Analysis Of Piezoelectric Microcantilever Sensors, Amin Salehi-Khojin May 2008

Vibration Analysis Of Piezoelectric Microcantilever Sensors, Amin Salehi-Khojin

All Dissertations

The main objective of this dissertation is to comprehensively analyze vibration characteristics of microcantilever-based sensors with application to ultra small mass detection and low dimensional materials characterization. The first part of this work focuses on theoretical developments and experimental verification of piezoelectric microcantilevers, commercially named Active Probes, which are extensively used in most today's advanced Atomic Force Microscopy (AFM) systems. Due to special geometry and configuration of Active Probes, especially multiple jump discontinuities in their cross-section, a general and comprehensive framework is introduced for forced vibration and modal analysis of discontinuous flexible beams. More specifically, a general formulation is obtained …


Laboratory Evaluation Of Chlorinated Ethene Transformation Processes In Fractured Sandstone, Ramona Darlington May 2008

Laboratory Evaluation Of Chlorinated Ethene Transformation Processes In Fractured Sandstone, Ramona Darlington

All Dissertations

A fractured sandstone aquifer at an industrial site in southern California is contaminated with trichloroethene (TCE) to depths in excess of 244 m. Field monitoring data suggest that TCE is undergoing reduction to cis-DCE and that additional attenuation is occurring. However, vinyl chloride (VC) and ethene have not been detected in significant amounts, so that if transformation is occurring, a process other than reductive dechlorination must be responsible. The overall objective of this study was to evaluate the occurrence of biotic and abiotic transformation processes at this site for TCE, cis-DCE and VC. Anaerobic microcosms were constructed with site groundwater …


Study Of Electrospinning Of Property-Modulated Biomedical Microfibers, Scott Taylor May 2008

Study Of Electrospinning Of Property-Modulated Biomedical Microfibers, Scott Taylor

All Dissertations

Electrospinning technologies have been of great interest in recent years, due in large part to developments in the field of Bioengineering, including the preparation of novel polymers and advances in tissue engineering, specifically for therapeutic applications. The electrospinning process is, in general, a very benign process that allows the preparation, under mild conditions, of micro- and nano-scale fibers from fiberforming materials, as well as traditionally non-fiber forming materials. This process is of specific interest to the biomedical community because it affords an opportunity to create highly-tailored novel constructs with a multitude of possible uses. Some proposed uses for these materials …