Digital Commons Network^™

Multiresolution Wavelet Analysis Of The Dynamics Of A Cracked Rotor, Jerzy T. Sawicki, Asok K. Sen, Grzegorz Litak

Mechanical Engineering Faculty Publications

We examine the dynamics of a healthy rotor and a rotor with a transverse crack, which opens and closes due to its self weight. Using discrete wavelet transform, we perform a multiresolution analysis of the measured vibration signal from each of these rotors. In particular, the measured vibration signal is decomposed into eight frequency bands, and the rms amplitude values of the healthy and cracked rotors are compared in the three lowest-frequency bands. The results indicate that the rms vibration amplitudes for the cracked rotor are larger than those of the healthy rotor in each of these three frequency bands. …

Nepa And The Dynamics Of Public Participation In The Environmental Review Process: An Analysis Of The Northmet (Polymet) Mining Project Near Hoyt Lakes Minnesota, Amber Neumann

Political Science Theses and Capstones

Hypothesis: That comments collected from agency “experts” during the scoping phase of the National Environmental Policy Act (NEPA) process would be disproportionately represented as changes in subsequent drafts of NorthMet’s Environmental Impact Statement (EIS).

Methods: Tabular analysis of data collected from the Minnesota DNR publication of Response to the Public Scoping Projects PolyMet Mining Inc.; NorthMet Project. 2005

Results: There is an excellent cross section of comment sources represented in changes to subsequent drafts of NorthMet’s EIS. A lot of overlap exists between various types of participants and their concerns, resulting in many of the successful comments stemming from …

An Architecture For High-Performance Privacy-Preserving And Distributed Data Mining, James Secretan

Electronic Theses and Dissertations

This dissertation discusses the development of an architecture and associated techniques to support Privacy Preserving and Distributed Data Mining. The field of Distributed Data Mining (DDM) attempts to solve the challenges inherent in coordinating data mining tasks with databases that are geographically distributed, through the application of parallel algorithms and grid computing concepts. The closely related field of Privacy Preserving Data Mining (PPDM) adds the dimension of privacy to the problem, trying to find ways that organizations can collaborate to mine their databases collectively, while at the same time preserving the privacy of their records. Developing data mining algorithms for …

Determining Emissions From Landfills And Creating Odor Buffer Distances, Nicholas Guarrieloo

Electronic Theses and Dissertations

With population growing every year, more and more people are looking for places to live. This can lead to construction of houses near and around landfills. As homes get closer to landfills, the odors these landfills produce become more of a problem, and lead to an increase in odor complaints. Modeling these odors and recommending odor buffer distances will help determine limits on how close to landfills new homes should be allowed. This should help reduce future odor complaints. To solve this problem one must accurately estimate odorous gas emissions from the landfill. Often odors can be indicated by methane …

Analyses Of Crash Occurence And Injury Severities On Multi Lane Highways Using Machine Learning Algorithms, Abhishek Das

Electronic Theses and Dissertations

Reduction of crash occurrence on the various roadway locations (mid-block segments; signalized intersections; un-signalized intersections) and the mitigation of injury severity in the event of a crash are the major concerns of transportation safety engineers. Multi lane arterial roadways (excluding freeways and expressways) account for forty-three percent of fatal crashes in the state of Florida. Significant contributing causes fall under the broad categories of aggressive driver behavior; adverse weather and environmental conditions; and roadway geometric and traffic factors. The objective of this research was the implementation of innovative, state-of-the-art analytical methods to identify the contributing factors for crashes and injury …

Sintering Additives For Nanocrystalline Titania And Processing Of Porous Bone Tissue Engineering Scaffolds, Arun Menon

Electronic Theses and Dissertations

Titania (Titanium dioxide, TiO2) has been researched as a promising biomaterial due to its excellent biocompatibility. However, the main limitation of titania is its poor mechanical properties which limit its use in many load-bearing applications. In this thesis report, the properties of titania were improved by doping with small quantities of MgO, ZnO and SiO2 as sintering additives. Nanocrystalline powder was selected, as it possesses outstanding properties over conventional coarse-grained powders due to reduced grain size. Nanocrystalline anatase powder of size 5-15 nm was synthesized via a simple sol-gel technique. Small quantities of dopants were introduced into pure titania powder, …

Occupational Lower Extremity Risk Assessment Modeling, Christopher Reid

Electronic Theses and Dissertations

Introduction: Lower extremity (LE) work-related musculoskeletal disorders (WMSDs) are known to occur with cumulative exposure to occupational and personal risks. The objective of this dissertation study was to find if creating a quantifiable risk detection model for the LE was feasible. The primary product of the literature review conducted for this study resulted in focusing the attention of the model development process onto creating the initial model of the LE for assessing knee disorder risk factors. Literature Review: LE occupational disorders affect numerous industries and thousands of people each year by affecting any one of the musculoskeletal systems deemed susceptible …

Structural Health Monitoring With Emphasis On Computer Vision, Damage Indices, And Statistical Analysis, Ricardo Zaurin

Electronic Theses and Dissertations

Structural Health Monitoring (SHM) is the sensing and analysis of a structure to detect abnormal behavior, damage and deterioration during regular operations as well as under extreme loadings. SHM is designed to provide objective information for decision-making on safety and serviceability. This research focuses on the SHM of bridges by developing and integrating novel methods and techniques using sensor networks, computer vision, modeling for damage indices and statistical approaches. Effective use of traffic video synchronized with sensor measurements for decision-making is demonstrated. First, some of the computer vision methods and how they can be used for bridge monitoring are presented …

A Study Of Central Florida Nonroad Voc And Nos Emissions And Potential Actions To Reduce Emissions, Michael Radford

Electronic Theses and Dissertations

Ground-level ozone is harmful to the human respiratory system, as well as the environment. The national EPA 8-hour ozone standard for ground-level ozone was reduced from 85 parts per billion (ppb) to 75 ppb in 2008, and trends from previous years show that some of the counties in Central Florida could be in danger of violation. Violation means "non attainment" status; in which the county is ordered by EPA to develop specific implementation plans to reduce its emissions. The objective of this study was to compile an emissions inventory of volatile organic compounds (VOCs) and nitrogen oxides (NOx) from nonroad …

Synthesis Of Best Practices In Transportation Security, Volume Ii: Emergency Response, Rodrigo Vargas, Jon D. Fricker

JTRP Technical Reports

Part I of the research focused on developing a methodology to identify and evaluate the most critical and vulnerable INDOT assets. This method aims at obtaining an index that reflects the vulnerability and criticality of an asset on the basis of multiple performance criteria. This methodology was tested on the seven INDOT districts. Because not all the factors that influence the vulnerability do have same weight, the analytical hierarchical process is used to obtain the weights for the criteria. Countermeasures are suggested as a part of the research to reduce the vulnerability of a given asset based on its relevant …

Effect Of Mechanical Vibrations On Light Emitting Diode Luminaires, Jayalakshmi Paladugu

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this work, a LED and two types of Compact fluorescent lamps were investigated for the intensity variation due to mechanical vibrations in the range of 0 to 30 HZ. In general, subjecting the lamps to 24-hour vibration affects the total intensity percentage variations of peak intensities after vibrations is in the range of -25 to +15% compared to those of no vibrations for the light emitting diode luminaires. For the case of compact fluorescent lamps (Nuvue) the variations are in range from +10 to +35%, whereas for the Compact fluorescent lamps (Ecosmart) the intensity peaks range from -10 to …

Quantity-Based Cost Forecasting System For Street Construction Projects, Nipesh Pradhananga

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction projects typically are not withdrawn after going into the competitive bidding process. The decision of contracting authorities regarding which projects will proceed to the bidding stage depends, in part, upon the early estimates of probable cost. Efforts are made to make this estimate as realistic as possible. Irrespective of the estimate of probable cost, the actual project cost is established by the amount of the winning bid.

This study analyzed historical bid data of street construction projects undertaken by the Public Works Department, Clark County, Nevada, from 1991 through 2006. The focus of this study was on utilizing statistical …

Parametric Study Of Efficiency Measures For Home Energy Conservation In Las Vegas, Nevada, Todd M. France

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pulte Homes, a production home builder and community developer partnering with the U.S. Department of Energy's Building America program, has collaborated with the Center for Energy Research at the University of Nevada, Las Vegas and NV Energy, the local electric utility, on an energy conservation project in the Las Vegas Valley.

This study entails four model homes at a new development in the Summerlin community of Las Vegas, Nevada, named Villa Trieste. The home models, ranging in floor plan area from 1,487 to 1,777 square feet, have been constructed under the Environments for Living program and are LEED (Leadership in …

Biomedical Technology: Supporting Movement, Petros Katsioloudis

STEMPS Faculty Publications

According to the National Institute on Disability and Rehabilitation Research, an estimated 8.5 million children 21 years and younger have a disability (Jans & Stoddard, 1999). After about a decade, with the development of new and sophisticated materials (aluminum alloys, titanium alloys, and carbon fibers) and the integration of electronics, it was then possible to significantly improve the performance of prostheses, built with the so-called endo skeletal (or skeletal-modular) method (Mora, Beratni & Pedrotti, 2006).

Response Of Academics To Demands For Change In Engineering Education, Kevin Kelly

Conference papers

This paper attempts to show what academics and other stakeholders think about academic change in an Institute of Technology in Ireland as this HEI attempts to respond to a rapidly changing external s becoming a university and moving to a new campus on a green field site. It is a summary of aspects of a doctoral thesis undertaken by an experienced academic that set out to explore how the unprecedented challenges now facing higher education internationally might best be met in the Dublin Institute of Technology. It is insider research and this paper identifies and examines barriers and enablers to …

Effects Of Physical And Mental Tasks On Heart Rate Variability, Satya Anasuya Paritala

LSU Master's Theses

Demands at work are associated with an increased risk of cardio vascular diseases, but little is known about its underlying connection. The purpose of this study was to evaluate the effects of physical and mental tasks that induced stress, on Heart Rate Variability (HRV). Another aim was to observe the trends in subjective workload ratings in conjunction with the physiological response of the heart and also to assess the comfort level of the participants while wearing the heart rate monitor and performing tasks. Heart rate was recorded while at rest and while performing the tasks. Subjective workload ratings were obtained …

Biocompatible/ Bioresorbable Polymer Based Silver Nanaomaterial Coatng For Chronic Indwelling Medical Devices And Bioscaffolds For Tissue Regrowth, Ammar T. Qureshi

LSU Master's Theses

The objective of this study is to synthesize and characterize antimicrobial, bio-polymer based silver nanomaterials composite coatings, for use in chronic indwelling medical devices, and bioscaffolds. The coatings and bioscaffolds are comprised of novel biomass mediated silver nano particles (SNP) that are biocompatible, highly concentrated, highly pure, cost-effective, polydispersed and compatible with a range of polymer systems applicable for use with existing chronic indwelling medical devices. This thesis is divided into three main chapters. In Chapter 1, detailed review on the need for antimicrobial nanocomposite coatings for chronic indwelling medical devices along with different SNP synthesis and characterization methods is …

A Decision Making Framework For Hurricane Evacuation And Sheltering, Jason Fennell

LSU Master's Theses

There are few tools currently available to emergency managers to assist in making decisions about whether to evacuate, shelter locally, or shelter-in-place, and none of these tools explicitly consider risk to life safety. A methodology was developed to provide risk-based guidance for evacuation versus sheltering decision making. The hurricane hazards considered in the developed methodology are high winds, storm surge flooding and waves, and rainfall flooding. Vulnerability of buildings to these hazards and the associated risks to life safety are then determined. These results are compared to the hazards and risks associated with evacuation, particularly for medical special needs populations …

Nano-Mechanics Of Cartilage Glycosaminoglycans Using Molecular Dynamics Methods, Kevin Neil Hendrickson

Master's Theses

Articular Cartilage (AC) is the main load carrying material in synovial joints {Hamerman, 1962} and degeneration of AC can cause pain in the form of arthritis. Current work is centered on the method of replacing damaged cartilage inside the body (in vivo) with tissue engineered outside the body (ex vivo) {Temenoff, 2000}. In order to engineer tissue ex vivo similar to the native tissue in structure and function there must be a comprehensive understanding of the mechanical properties of AC. This work focuses on the study of glycosaminoglycans (GAGs), a molecule known to be primarily responsible for the compressive stiffness …

Telecommunications Liberalisation In Africa: Proposed Regulatory Model For The Sadc Region, Z. N. Jobodwana

Journal of Digital Forensics, Security and Law

The liberalisation of the telecommunication industry in Africa, and the further development of the region’s physical infrastructure was accompanied by the further development of Africa’s information, communication and technology infrastructure. Competition within the industry stimulated heavy economic investment in other sectors of the economy. The outcome of liberalisation also included the establishment of community-based structures that continue to enable communities to manage their own development and gain access to information and communication technologies (ICTs) in an unprecedented manner. The telecommunication infrastructure further stimulated the fast development of other related services, for example, ecommerce and mobile commerce (m-commerce), e-government, internet banking, …

Numerical Modeling For Long Term Performance Of Soil-Bentonite Cut-Off Walls In Unsaturated Soil Zone, Sukanta Chakraborty

LSU Master's Theses

ABSTRACT The construction practices of containment walls are extremely important in this competitive economic market, but development is limited. Unsaturated zone is an integral part of the geotechnical problems, as it affects on any kind of soils structures. The unsaturated zone plays significant role in many aspects of water flow and contaminant transport, including containment system such as: cut-off walls, infiltration, soil moisture storage, evaporation, plant water uptake, ground water recharge, erosion, and runoff. This research focuses on the hydraulic sustainability and performance of soil-bentonite cutoff walls (Britton et al, 2004) models showing hydraulic behavior of barrier walls. The cutoff …

Understanding The Development Of Infant Feeding: A Spectral Analysis Approach, Pooja Vijaygopal

University of Kentucky Master's Theses

Feeding problems in preterm neonates stem from complications of early delivery. Attainment of independent feeding is a prerequisite for Neonatal Intensive Care Unit (NICU) discharges. Some quantitative studies of infant feeding involve excessive amounts of time for data processing. Multivariate spectral analysis was used to minimize time for investigation of variability in these rhythms. Auto and Cross-spectral parameters of the rhythms were correlated with Gestational Age (GA), Postmenstrual Age (PMA), Birthweight (BW), Days of Life (DOL), and Time Since First Nipple feeding (TSFN). Auto-spectral analysis showed 25.55% increase in Bandwidth of suck (bw-su) for a 2-week increase in GA (DOL …

A Novel Reconfigurable Optical Interconnect Architecture Using An Opto-Vlsi Processor And A 4-F Imaging System, Mingya Shen, Feng Xiao, Kamal Alameh

Research outputs pre 2011

A novel reconfigurable optical interconnect architecture for on-board high-speed data transmission is proposed and experimentally demonstrated. The interconnect architecture is based on the use of an Opto-VLSI processor in conjunction with a 4-f imaging system to achieve reconfigurable chip-to-chip or board-to-board data communications. By reconfiguring the phase hologram of an Opto-VLSI processor, optical data generated by a vertical Cavity Surface Emitting Laser (VCSEL) associated to a chip (or a board) is arbitrarily steered to the photodetector associated to another chip (or another board). Experimental results show that the optical interconnect losses range from 5.8dB to 9.6dB, and that the maximum …

Distributed Optical Fibre Smart Sensors For Structural Health Monitoring: A Smart Transducer Interface Module, Graham Wild, Steven Hinckley

Research outputs pre 2011

In this paper, we present a smart transducer interface module (STIM) for distributed optical fibre smart sensors. The STIM is a general purpose interface that has been designed to be used with intensiometric optical fibre sensors. The interface is made up of 2 optical fibre PIN receivers, a differential amplifier and a digital signal processor. The two received signals are differentially amplified to increase sensitivity and the signal-to-noise ratio. A DSP evaluation board is used as the intelligence of the STIM, which has onboard ADC. The STIM was successfully used as an embedded system monitoring both temperature and strain, and …

Opto-Vlsi-Based Tunable Single-Mode Fiber Laser, Feng Xiao, Kamal Alameh, Yong-Tak Lee

Research outputs pre 2011

A new tunable fiber ring laser structure employing an Opto-VLSI processor and an erbium-doped fiber amplifier (EDFA) is reported. The Opto-VLSI processor is able to dynamically select and couple a waveband from the gain spectrum of the EDFA into a fiber ring, leading to a narrow-linewidth high-quality tunable laser output. Experimental results demonstrate a tunable fiber laser of linewidth 0.05 nm and centre wavelength tuned over the C-band with a 0.05nm step. The measured side mode suppression ratio (SMSR) is greater than 35 dB and the laser output power uniformity is better than 0.25 dB. The laser output is very …

Tunable Photonic Microwave Filters Based On Opto-Vlsi Processors, Feng Xiao, Budi Juswardy, Kamal Alameh

Research outputs pre 2011

A tunable photonic microwave filter structure utilizing an opto-very-large scale integration (opto-VLSI) processor is proposed and experimentally demonstrated. The opto-VLSI processor slices a radio-frequency (RF)-modulated wideband light source into wavebands of arbitrary weights and incremental delay times to realize a tunable RF filter response. Experimental results demonstrate a tunable microwave filter that can simply be reconfigured with high flexibility via a software-driven opto-VLSI processor. Theoretical simulations are in good agreement with the experimental results.

Tunable Multi-Wavelength Fiber Lasers Based On An Opto-Vlsi Processor And Optical Amplifiers, Feng Xiao, Kamal Alameh, Yong Lee

Research outputs pre 2011

A multi-wavelength tunable fiber laser based on the use of an Opto-VLSI processor in conjunction with different optical amplifiers is proposed and experimentally demonstrated. The Opto-VLSI processor can simultaneously select any part of the gain spectrum from each optical amplifier into its associated fiber ring, leading to a multiport tunable fiber laser source. We experimentally demonstrate a 3-port tunable fiber laser source, where each output wavelength of each port can independently be tuned within the C-band with a wavelength step of about 0.05nm. Experimental results demonstrate a laser linewidth as narrow as 0.05 nm and an optical side-mode-suppression-ratio (SMSR) of …

Opto-Vlsi-Based Broadband True-Time Delay Generation For Phased Array Beamforming, Budi Juswardy, Feng Xiao, Kamal Alameh

Research outputs pre 2011

Electronically controlled phased-array antennas can adaptively scan radiated beams in three-dimensional space without mechanically moving parts. While most of the research on phased-array antennas has been focusing on broadband beam steering less attention has been devoted to null steering. Broadband null steering requires a beamformer that can generate variable and frequency independent true time-delays (TTD). In this paper we propose and demonstrate the concept of an Opto-VLSI-based tunable true-time delay generation unit for adaptive null steering in phased array antennas, where arbitrary single or multiple true-time delays can simultaneously be synthesized. Simulated azimuth gain patterns for a 4- element antenna …

Photonic True-Time Delay Unit For Broadband Adaptive Nulling In Antenna Arrays, Budi Juswardy, Feng Xiao, Kamal Alameh

Research outputs pre 2011

This paper describes an opto-VLSI-based tunable true-time delay generation unit used for adaptive null steering in phased array antennas. Arbitrary single or multiple true-time delays can simultaneously be synthesized for each antenna element to generate multiple broadband nulls. Simulated azimuth gain patterns for a 4-elements antenna arrays are presented. Experimental results, which demonstrate the principle of the true-time delay unit are also presented.

Opto-Vlsi-Based Photonic True-Time Delay Architecture For Broadband Adaptive Nulling In Phased Array Antennas, Budi Juswardy, Feng Xiao, Kamal Alameh

Research outputs pre 2011

This paper proposes a novel Opto-VLSI-based tunable true-time delay generation unit for adaptively steering the nulls of microwave phased array antennas. Arbitrary single or multiple true-time delays can simultaneously be synthesized for each antenna element by slicing an RFmodulated broadband optical source and routing specific sliced wavebands through an Opto-VLSI processor to a high-dispersion fiber. Experimental results are presented, which demonstrate the principle of the true-time delay unit through the generation of 5 arbitrary true-time delays of up to 2.5 ns each.