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Full-Text Articles in Engineering

Rate Alterable Traumatic Brain Injury Device For Rodent Models, Radia Abdul Wahab Jan 2014

Rate Alterable Traumatic Brain Injury Device For Rodent Models, Radia Abdul Wahab

Dissertations

Traumatic Brain Injury (TBI) is a physical impact to the head resulting in functional deficits in memory and motor systems. TBI is a prevalent problem occurring in 1.7 million people annually in the United States (Faul et al. 2010). TBIs can differ greatly in terms of the biomechanics of the impact such as magnitude, direction and rate. Indeed, it is likely that the wide range of TBI outcomes may be due to the physical characteristics of the trauma. Studies to date on impact have used injury devices with limited alterable parameters. Therefore, the existing impact studies have considered the effect …


The Effect Of Mechanical Vestibular Stimulation On Muscle Tone And Spasticity In Individuals With Neurological Impairment, Ghaith J. Androwis Jan 2014

The Effect Of Mechanical Vestibular Stimulation On Muscle Tone And Spasticity In Individuals With Neurological Impairment, Ghaith J. Androwis

Dissertations

In the desire to better understand spasticity mainly in Cerebral Palsy (CP) and to examine vestibular stimulation as a future intervention for .muscle tone reduction, and to be able to describe the change in level of spasticity in subjects with disability and describe interventions effects, a series of experiments are done on children with spasticity. In addition to understanding the otoliths in the vestibular system and their projections, properties and pathways a more important major objective of this work is to validate the changes in otoliths signal caused by vestibular stimulation based on the Equilibrium Point Hypothesis and the inclusion …


Analyses Of Groundwater Contribution To A Riverine Wetland, Farzad Mahmoodinobar Jan 2014

Analyses Of Groundwater Contribution To A Riverine Wetland, Farzad Mahmoodinobar

Dissertations

Rainfall, runoff, overbank flow and groundwater, all contribute water to wetlands. Each transport element is associated with unique modeling approaches and uncertainties. Transpiration is perhaps the hardest to quantify as it is subject to all the variability of plant growth. Transpiration causes land area to lose moisture and the loss amount depends on precipitation incidence, the temperature and type and extent of vegetation. Plants can intercept virtually all recharge during the growing season and almost none from late fall to early spring in northeastern United States. Thus, an improvement in the transpiration element can contribute considerably to an improved groundwater …


Discrete Element Method Based Scale-Up Model For Material Synthesis Using Ball Milling, Priya Radhi Santhanam Jan 2014

Discrete Element Method Based Scale-Up Model For Material Synthesis Using Ball Milling, Priya Radhi Santhanam

Dissertations

Mechanical milling is a widely used technique for powder processing in various areas. In this work, a scale-up model for describing this ball milling process is developed. The thesis is a combination of experimental and modeling efforts.

Initially, Discrete Element Model (DEM) is used to describe energy transfer from milling tools to the milled powder for shaker, planetary, and attritor mills. The rolling and static friction coefficients are determined experimentally. Computations predict a quasi- steady rate of energy dissipation, Ed, for each experimental configuration. It is proposed that the milling dose defined as a product of Ed and milling …


Construction And Assessment Of A Computer Graphics-Based Model For Wheelchair Propulsion, Brooke Marie Odle Jan 2014

Construction And Assessment Of A Computer Graphics-Based Model For Wheelchair Propulsion, Brooke Marie Odle

Dissertations

Upper limb overuse injuries are common in manual wheelchair using persons with spinal cord injury (SCI), especially those with tetraplegia. Biomechanical analyses involving kinetics, kinematics, and muscle mechanics provide an opportunity to identify modifiable risk factors associated with wheelchair propulsion and upper limb overuse injuries that may be used toward developing prevention and treatment interventions. However, these analyses are limited because they cannot estimate muscle forces in vivo. Patient-specific computer graphics-based models have enhanced biomechanical analyses by determining in vivo estimates of shoulder muscle and joint contact forces. Current models do not include deep shoulder muscles. Also, patient-specific models …


Extracting Product Development Intelligence From Web Reviews, Ismail Artun Yagci Jan 2014

Extracting Product Development Intelligence From Web Reviews, Ismail Artun Yagci

Dissertations

Product development managers are constantly challenged to learn what the consumer product experience really is, and to learn specifically how the product is performing in the field. Traditionally, they have utilized methods such as prototype testing, customer quality monitoring instruments, field testing methods with sample customers, and independent assessment companies. These methods are limited in that (i) the number of customer evaluations is small, and (ii) the methods are driven by a restrictive structured format. Today the web has created a new source of product intelligence; these are unsolicited reviews from actual product users that are posted across hundreds of …


Influence Of Beach Hydrodynamics On Saltwater Transport And Oil Persistence In Beaches, Ali Abdollahi-Nasab Jan 2014

Influence Of Beach Hydrodynamics On Saltwater Transport And Oil Persistence In Beaches, Ali Abdollahi-Nasab

Dissertations

The exchange of water and solutes across the aquifer-ocean interface plays an important ecological role in both aquifer and the open water. Saltwater intrusion could prevent utilization of groundwater for either drinking water or irrigation. In addition, the flux of solutes, such as nutrients, from inland groundwater sources plays an important role in shoreline ecology, especially in embayments. This research relies on a three-pronged approach, involving a laboratory beach experiment, field scale experiments and numerical analyses. The laboratory beach experiment is designed to investigate the fundamental processes occurring in beach aquifers. It explores the effects of buoyancy (or lack thereof) …


Performance Analysis And Scheduling Strategies For Ambulatory Surgical Facilities, Xuanqi Zhang Jan 2014

Performance Analysis And Scheduling Strategies For Ambulatory Surgical Facilities, Xuanqi Zhang

Dissertations

Ambulatory surgery is a procedure that does not require an overnight hospital stay and is cost effective and efficient. The goal of this research is to develop an ASF operational model which allows management to make key decisions. This research develops and utilizes the simulation software ARENA based model to accommodate: (a) Time related uncertainties – Three system uncertainties characterize the problem (ii) Surgery time variance (ii) Physician arrival delay and (iii) Patient arrival delay; (b) Resource Capture Complexities – Patient flows vary significantly and capture/utilize both staffing and/or physical resources at different points and varying levels; and (c) Processing …


Computational Optimization Methods For Modeling The Effect Of Muscle Forces On Bone Strength Adaptation, Catherine Siena Florio Jan 2014

Computational Optimization Methods For Modeling The Effect Of Muscle Forces On Bone Strength Adaptation, Catherine Siena Florio

Dissertations

An improved understanding of the mechanical influences that alter the strength of a bone can aid in the refinement of the wide array of currently available techniques to counteract the losses of bone strength that occur due to age or disuse both on Earth and in Space. To address this need, computational modeling methods to quantitatively analyze and compare the effects of mechanical factors on the strength of a targeted bone within a multibone, multimuscle system are developed and implemented in this work. Through a more detailed representation of the system in which the bone acts and the creation of …


In Vitro Modeling And Analysis Of Axon Stretch Growth For The Sustained Growth Of Long Nerve Fibers, Joseph Rocco Loverde Jan 2014

In Vitro Modeling And Analysis Of Axon Stretch Growth For The Sustained Growth Of Long Nerve Fibers, Joseph Rocco Loverde

Dissertations

The integration of long nerve fibers throughout the body is distinctive among somatic tissues. Single, individual motor neurons grow to a meter in length or more as they maintain connectivity with sacral areas of the spinal cord from the brain. Similarly, homologous growth also occurs via spinal ganglion neurons within the peripheral nervous system. The most widely studied aspect of nerve development has been the migration and extension of growth cones towards synaptic targets during early development. However, following growth cone extension, axonal fibers continue to grow in synchrony with the expansion of limbs and mit otic tissues throughout childhood …


Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera Jan 2014

Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera

Dissertations

This research presents a novel fully integrated energy harvester, matching network, multi-stage RF-DC rectifier, mode selector, RC oscillator, LC oscillator, and X-band power amplifier implemented in IBM 0.18-µm RF CMOS technology. We investigated different matching schemes, antennas, and rectifiers with focus on the interaction between building blocks. Currently the power amplifier gives the maximum output power of 5.23 dBm at 9.1GHz. The entire RFID tag circuit was designed to operate in low power consumption. Voltage sensor circuit which generates the enable signal was designed to operate in very low current. All the test blocks of the RFID tag were tested. …


Intelligent Approaches For Modeling And Optimizing Hvac Systems, Iii Raymond Tesiero Jan 2014

Intelligent Approaches For Modeling And Optimizing Hvac Systems, Iii Raymond Tesiero

Dissertations

Advanced energy management control systems (EMCS), or building automation systems (BAS), offer an excellent means of reducing energy consumption in heating, ventilating, and air conditioning (HVAC) systems while maintaining and improving indoor environmental conditions. This can be achieved through the use of computational intelligence and optimization. This research will evaluate model-based optimization processes (OP) for HVAC systems utilizing MATLAB, genetic algorithms and self-learning or self-tuning models (STM), which minimizes the error between measured and predicted performance data. The OP can be integrated into the EMCS to perform several intelligent functions achieving optimal system performance. The development of several self-learning HVAC …


Energy Optimization Of A Free-Piston Enhanced Hybrid Vehicle, Kenneth Jarod Jones Jan 2014

Energy Optimization Of A Free-Piston Enhanced Hybrid Vehicle, Kenneth Jarod Jones

Dissertations

The world’s heavy dependence on vehicles which utilize hydrocarbon fuels as a primary power source has renewed the interest in electric and hybrid vehicles for industrial, commercial, and public use. The primary objective of this movement is centered on increased efficiency in energy usage for transportation. Hybrid vehicles which utilize an internal combustion engine as a linear generator, converting energy stored in hydrocarbon fuels into electrical power, could serve as a transitioning technology. The free-piston enhanced hybrid vehicle (FPHV) could potentially fill this role. The present work contains a theoretical and numerical approach to analyzing and optimizing the usage of …


Cmos Rotary Traveling Wave Oscillators (Rtwos), Marvin Aidoo Jan 2014

Cmos Rotary Traveling Wave Oscillators (Rtwos), Marvin Aidoo

Dissertations

Rotary Traveling Wave Oscillator (RTWO) represents a transmission line based technology for multi-gigahertz multiple phase clock generation. RTWO is known for providing low jitter and low phase noise signals but the issue of high power consumption is a major drawback in its application. Direction of wave propagation is random and is determined by the least resistance path in the absence of an external direction control circuit. The objective of this research is to address some of the problems of RTWO design, including high power consumption, uncertainty of propagation direction and optimization of design variables. Included is the modeling of RTWO …


Wind Energy In Ireland - An Analysis Of Percentage Error In Forecasting, Michael Mcdonald Jan 2014

Wind Energy In Ireland - An Analysis Of Percentage Error In Forecasting, Michael Mcdonald

Dissertations

This research aimed to examine the percentage error in forecasting of wind energy using datasets from a small wind farm in Ireland. Furthermore, the study aimed to compare this calculated data to the national forecasting percentage errors. Internationally, the electrical sector and society are undergoing a revolution in terms of 'green economy'. This paradigm shift towards renewable energy technologies is recognised as a priority, with diminution of finite fossil fuels at its core. Renewable energy as a sector has provided significant financial stimulation to global economies in recent years. Moreover, wind energy has provided significant amounts of clean electricity throughout …


Effect Of Electrospun Nanofibers On The Short Beam Strength Of Laminated Fiberglass Composite, Dattaji K. Shinde Jan 2014

Effect Of Electrospun Nanofibers On The Short Beam Strength Of Laminated Fiberglass Composite, Dattaji K. Shinde

Dissertations

High specific modulus and strength are the most desirable properties for the material used in structural applications. Composite materials exhibit these properties and over the last decade, their usage has increased significantly, particularly in automotive, defense, and aerospace applications. The major cause of failures in composite laminates is due to delaminations. Delamination in composite laminates can occur due to fatigue, low velocity impact and other loadings modes. Conventional methods like “through-the-thickness stitching” or “Z-Pinning” have limitations for improving flexural and interlaminar properties in woven composites due to the fact that while improving interlaminar properties, the presence of stitches or Z …


Synergy Of The Developed 6d Bim Framework And Conception Of The Nd Bim Framework And Nd Bim Process Ontology, Shawn Edward O'Keeffe Dec 2013

Synergy Of The Developed 6d Bim Framework And Conception Of The Nd Bim Framework And Nd Bim Process Ontology, Shawn Edward O'Keeffe

Dissertations

The author developed a unified nD framework and process ontology for Building Information Modeling (BIM). The research includes a framework developed for 6D BIM, nD BIM, and nD ontology that defines the domain and sub-domain constructs for future nD BIM dimensions. The nD ontology defines the relationships of kinds within any new proposed dimensional domain for BIM. The developed nD BIM framework and ontology takes into account the current 2D-5D BIM dimensions. There is a synergy between the 6D and nD framework that allows the nD framework and ontology to be utilized as a unified template for future dimensional development. …


Single Case Research Designs: An Effective And Efficient Methodology For Applied Aviation Research, Geoffrey R. Whitehurst Dec 2013

Single Case Research Designs: An Effective And Efficient Methodology For Applied Aviation Research, Geoffrey R. Whitehurst

Dissertations

The purpose of this three-paper dissertation is to examine the potential of single case research designs (SCDs) as an appropriate and efficient experimental design for use in applied aviation research. In the current environment of dwindling resources, funding for experiments requiring large sample sizes, a normal requirement for between-group designs, is becoming difficult to find. However, the need to improve safety within the aviation industry is an ongoing requirement, especially as advances in technology continue have an impact on how the industry operates. SCDs are experimental designs that require very few participants and therefore have the potential to save time …


New Fault Tolerant Multicast Routing Techniques To Enhance Distributed-Memory Systems Performance, Masoud Esmail Masoud Shaheen Dec 2013

New Fault Tolerant Multicast Routing Techniques To Enhance Distributed-Memory Systems Performance, Masoud Esmail Masoud Shaheen

Dissertations

Distributed-memory systems are a key to achieve high performance computing and the most favorable architectures used in advanced research problems. Mesh connected multicomputer are one of the most popular architectures that have been implemented in many distributed-memory systems. These systems must support communication operations efficiently to achieve good performance. The wormhole switching technique has been widely used in design of distributed-memory systems in which the packet is divided into small flits. Also, the multicast communication has been widely used in distributed-memory systems which is one source node sends the same message to several destination nodes. Fault tolerance refers to the …


Investigation Of Recycled Paper Deinking Mechanisms, Veronika Husovska Dec 2013

Investigation Of Recycled Paper Deinking Mechanisms, Veronika Husovska

Dissertations

The use of water-based inks is on the rise. Sub-micron pigment particles are used for flexographic and inkjet water-based inks. Conventional deinking eliminates larger particles than those from these new ink systems. Therefore, water-based inks represent recycling difficulty.

Deinking experiments of water-based inks are carried out. The deinking strategy initially investigated elimination of pressure sensitive adhesive due to similar acrylic polymer chemistry used in water based inks. The impact of pH on stickies and ink agglomeration during deinking is studied. Experiments in acidic regions show growth of acrylic inks and stickies agglomerates, simplifying elimination.

Pre-recycling of water-based inks is explored. …


Optimization Of Path Based Sensor Spacing On A Freeway Segment For Travel Time Prediction During Incidents, Patricia Kathleen Dijoseph Aug 2013

Optimization Of Path Based Sensor Spacing On A Freeway Segment For Travel Time Prediction During Incidents, Patricia Kathleen Dijoseph

Dissertations

Congestion on freeways is increasing and a key source of it is non-recurring incidents. Accurate vehicle travel time predictions are needed during these incidents in order for roadway users to make informed trip decisions. Path based sensors are becoming a leading technology in gathering real-time travel time data. The data is used to make travel time predictions that are then provided through various means, such as dynamic message signs, to roadway users. These types of sensor are located at stationary points along a roadway and collect individual vehicle travel time data from vehicles as they drive pass the sensors.

The …


Exploitation Of Infrared Polarimetric Imagery For Passive Remote Sensing Applications, Joao Miguel Mendes Romano Aug 2013

Exploitation Of Infrared Polarimetric Imagery For Passive Remote Sensing Applications, Joao Miguel Mendes Romano

Dissertations

Polarimetric infrared imagery has emerged over the past few decades as a candidate technology to detect manmade objects by taking advantage of the fact that smooth materials emit strong polarized electromagnetic waves, which can be remotely sensed by a specialized camera using a rotating polarizer in front of the focal plate array in order to generate the so-called Stokes parameters: S0, S1, S2, and DoLP. Current research in this area has shown the ability of using such variations of these parameters to detect smooth manmade structures in low contrast contrast scenarios.

This dissertation proposes …


Batch And Continuous Production Of Stable Dense Suspensions Of Drug Nanoparticles In A Wet Stirred Media Mill, Afolawemi Afolabi Aug 2013

Batch And Continuous Production Of Stable Dense Suspensions Of Drug Nanoparticles In A Wet Stirred Media Mill, Afolawemi Afolabi

Dissertations

One way to improve the bioavailability of poorly water-soluble drugs is to reduce particle size of drug crystals down to nanoscale via wet stirred media milling. An increase in total surface area per mass loading of the drug and specific surface area as well as reduced external mass transfer resistance allow a faster dissolution of the poorly-water soluble drug from nanocrystals. To prevent aggregation of nanoparticles, polymers and surfactants are dissolved in water acting as stabilizers via adsorption onto the drug crystals.

In the last two decades, ample experimental data were generated in the area of wet stirred media milling …


Characterization Of Neural Ion Regulation Dysfunction During Insult And Evaluation Of Micro-Opioid Receptor Activation During Simulated Ischemia In The Pre-Botzinger Complex, Kyle F. Dobiszewski Aug 2013

Characterization Of Neural Ion Regulation Dysfunction During Insult And Evaluation Of Micro-Opioid Receptor Activation During Simulated Ischemia In The Pre-Botzinger Complex, Kyle F. Dobiszewski

Dissertations

The health and vitality of brain tissue is dependent upon the cells' abilities to maintain ionic homeostasis across their plasma membranes. Even slight alterations in intracellular or extracellular can have a devastating effect on excitability and neural vitality. This thesis investigates several concepts related to ion flux. First, it investigates how ion flux affects characterization of brain tissue by dielectric spectroscopy and what can be done to overcome that effect. Second, it investigates how ion flux can be used to describe the state of health of the tissue. Finally, it investigates if pharmacological intervention can attenuate some of the deleterious …


A Framework For Guiding Transportation Improvements To Support Desired Land Use, Jiruttichut Leoviriyakit Aug 2013

A Framework For Guiding Transportation Improvements To Support Desired Land Use, Jiruttichut Leoviriyakit

Dissertations

There is a growing recognition that transportation and land use policies cannot succeed independently of one another. The interactions between them must be understood, analyzed, and accounted for in order for land use and transportation plans and policies to be effective and successful. A methodological framework is presented that can help urban planners determine what outcomes can be expected in terms of change in land use patterns within the targeted communities and within the county should a transportation project be undertaken.

The framework is based on an interaction between travel demand model TRANSIMS and land use model TELUM that enables …


Pressure Swing Membrane Absorption Process For Separation Of Low Temperature Post-Shift Reactor Syngas, John Chau Aug 2013

Pressure Swing Membrane Absorption Process For Separation Of Low Temperature Post-Shift Reactor Syngas, John Chau

Dissertations

This thesis is concerned with a cyclic pressure swing membrane absorption process (PSMAB) for separation of the feed gas mixture containing —40% CO2-He balance using pure ionic liquid, 1-butyl-3-methylimidazolium dicyanamide ([bmim][DCA]), and its solution containing poly(amidoamine) (PAMAM) dendrimer Gen 0 primarily with a dry feed gas. An advanced pressure swing membrane absorption process is developed to produce purified He as a surrogate for H2 at a high pressure from simulated low- temperature shifted syngas for different membrane modules. The PSMAB process also simultaneously produces a highly purified CO2 stream containing bulk of the CO2 in …


New Approaches On Deinking Evaluations, Roland Gong Aug 2013

New Approaches On Deinking Evaluations, Roland Gong

Dissertations

Paper recycling in the U.S. is the most successful program of environmental sustainability. Approximately two thirds of consumed paper products were recycled, according to the EPA and AF&PA. However, domestic mills only applied one third of recycled fibers into new products, which is much lower than reported in China (67%). The domestic recycle mills claimed that outdated facilities, poor recycled fiber quality and high manufacturing cost are the major issues. They also said that these recycle mills have been put in a “no-win” position, which threatens the whole recycling loop eventually. A case study about Chinese recycle mills has been …


Organic Solar Cells Based On High Dielectric Constant Materials: An Approach To Increase Efficiency, Khalil Jumah Tawfiq Hamam Jun 2013

Organic Solar Cells Based On High Dielectric Constant Materials: An Approach To Increase Efficiency, Khalil Jumah Tawfiq Hamam

Dissertations

The efficiency of organic solar cells still lags behind inorganic solar cells due to their low dielectric constant which results in a weakly screened columbic attraction between the photogenerated electron-hole system, therefore the probability of charge separating is low. Having an organic material with a high dielectric constant could be the solution to get separated charges or at least weakly bounded electron-hole pairs. Therefore, high dielectric constant materials have been investigated and studied by measuring modified metal-phthalocyanine (MePc) and polyaniline in pellets and thin films. The dielectric constant was investigated as a function of temperature and frequency in the range …


Global Skin Friction Diagnostics: The Glof Technique And Measurements Of Complex Separated Flows, Sudesh A. Woodiga Jun 2013

Global Skin Friction Diagnostics: The Glof Technique And Measurements Of Complex Separated Flows, Sudesh A. Woodiga

Dissertations

This work describes the application of the global luminescent oil film skin friction meter to quantitative global skin friction diagnostics of complex separated flows. The development of this technique is based on the relationship between the oil film thickness and luminescent intensity of a luminescent oil film. The projected thin oil film equation is given to relate the normalized luminescent intensity with skin friction. The variational formulation with a smoothness constraint on skin friction is proposed to obtain a snap shot solution from two consecutive images for a relative skin friction field. A complete skin friction field is reconstructed through …


Adaptive Data Acquisition For Communication Networks, Behzad Ahmadi May 2013

Adaptive Data Acquisition For Communication Networks, Behzad Ahmadi

Dissertations

In an increasing number of communication systems, such as sensor networks or local area networks within medical, financial or military institutions, nodes communicate information sources (e.g., video, audio) over multiple hops. Moreover, nodes have, or can acquire, correlated information sources from the environment, e.g., from data bases or from measurements. Among the new design problems raised by the outlined scenarios, two key issues are addressed in this dissertation: 1) How to preserve the consistency of sensitive information across multiple hops; 2) How to incorporate the design of actuation in the form of data acquisition and network probing in the optimization …