Engineering Commons^™

Development Of Magnetic-Based Multi-Layer Microparticles For Stem Cell Isolation, Enrichment And Detachment, Sonia Santimano

Bioengineering Theses - Archive

Stem cells have been studied and used in several cell-based therapies for regenerative medicine, 3D tissue-engineered scaffolds, and in vitro models for drug screening and testing. For instance, cell based therapy via the use of stem cells like Endothelial Progenitor Cells (EPCs) to treat patients with cardiovascular diseases, including ischemic heart disease, in-stent restenosis, and peripheral arterial occlusive disease. In addition, Circulating Cancer Cells (CSCs) have been used as an indication of cancer progression-free survival and for studying the mechanisms of tumor formation, metastasis, and anti-cancer drug screening. Due to their extensive diagnostic and therapeutic potential, various techniques have been …

Quantification And Comparisons Of Motion Metrics For Finger Tapping Performed By Children With Cerebral Palsy Before And After Therapy With Two Motion Tracking Camera Systems, Ankita H. Chainani

Bioengineering Theses - Archive

The quantification of any improvements in the use of a paretic arm after children with cerebral palsy (CP) undergo rehabilitation is currently done by occupational therapists who administer a series of manual ability tests and assign a subjective score for each test task performed. In this work the hypothesis was explored of whether quantification of hand motion metrics by motion tracking while children with CP performed a hand tapping task could be used as a more quantitative surrogate for assessing how well these children control the use of their hand. To that end, two children with CP, both classified as …

Spectrophotometric Quantification Of Bilirubin In Sclera Of The Eye Using Visible Dlp® Hyperspectral Imaging, Naveen Balaji Balasubramanian

Bioengineering Theses - Archive

In clinical settings doctors strive to give best care to the patients by looking for methods to diagnose the illness early to intervene with the necessary treatment. In the case of patients with liver problems (e.g. cirrhosis, hepatitis) an early indicator of impaired liver function is an increased concentration of bilirubin in the blood circulation. Bilirubin concentration is currently quantified by blood sampling, which is invasive, and it would be desirable to have a technology that quantifies bilirubin non-invasively. The goal of this work was to help address this clinical need and develop a methodology for determining non-invasively a measure …

Antimicrobial Properties Of Citric Acid Based Polymers, Lee-Chun Su

Bioengineering Theses - Archive

A series of citric acid derived polymers synthesized in our lab were investigated and compared for their physiochemical and antimicrobial properties. We selected citric acid based polymers since citric acid is a product of natural metabolism. These polymers are not only biocompatible but also possess an antimicrobial effect. In polymer synthesis, citric acid (CA) provides profound functional groups available for binding and crosslinking to allow the controllable crosslinking degrees of polymers. A number of citric acid based polymers has been synthesized and studied for their chemical, mechanical, and biological characteristics for use in various biomedical applications. Since bacterial infections became …

Regenerative Peripheral Nerve Interfacing Of Sensory Modalities, Nilanjana T. Dutta

Bioengineering Theses - Archive

Peripheral neural interfaces (PNI) has proved potential to record motor commands for the control of these prosthetic limbs, together with stimulation of specific sensory axons, so as to transmit specific sensory sub-modalities. Although PNI is hypothesized to provide adequate sensory feedback, realizing this degree of specificity is not fully established. Recently, a regenerative multi-electrode interface (REMI) was reported to be capable of recording peripheral nerve activity from a transected nerve. This study is aimed at interfacing neural activity specific to sensory sub-modalities, such as thermal pain, mechanoception and limb stretching using the REMI, in a freely moving animal. In the …

Characterization Of Immune Response And Peripheral Nerve Regeneration Of Implanted Regenerative Multi-Electrode Interface Post-Subchronic Amputation, Camilo Andres Sanchez Useche

Bioengineering Theses - Archive

Interfacing high degree-of-freedom robotic prosthetics directly to the peripheral nervous system aims at improving the quotidian life of amputees. Despite advancements in robotics that have lead to human-like upper limb prosthetics, long-term interfacing has not been accomplished, thus voiding them from clinical use. Interfacing electrodes in the central nervous system fail due to the foreign body reaction and glial scar formation at the site of implantation. Concrete mechanisms for the failure of long-term Interfacing at the peripheral nervous level remain unclear. A regenerative multi-electrode interface (REMI) which allows for action potential recording as early as 7 days and provides support …

Development Of A Measurement System For Quantifying Ultrasound Field Distribution Of Different Transducers, Jayanth Kandukuri

Bioengineering Theses - Archive

Ultrasound has been widely used in many fields, such as nondestructive examination and medical imaging. Ultrasound is mostly characterized by its pressure and, dynamic pressure wave can be considered to be the foundation of ultrasound physics and imaging techniques. It is thus important for understanding ultrasound pressure properties to that of ultrasound intensity. Moreover, there are many applications that require mainly characterizing ultrasound pressure field (instead of intensity field alone). Therefore, reconstruction of an ultrasound pressure field is highly desirable not only for education but also for research. There may be some commercially available systems that can be used for …

Using An Ahp/Anp Hybrid Methodology For Freight Transport Networks Selection Towards Sustainable Transportation, Andrea M. Graham

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The selection of an effective transportation network for the transport of container freight is one of the most important factors in supply chain and logistics planning. The current transport networks, hub-and-spoke and point-to-point, although optimal in many aspects are still plagued with issues in route optimization, empty travel, and bad intermodal synchronization. The trucking industry, the most utilized of all modes, offers unsustainable components in its current state that continually introduce negative impacts to an ever evolving supply chain network. This research investigates a third potentially more sustainable distributed multi-segment transportation network. This network will be compared to the traditional …

Constraint Optimal Selection Techniques (Costs) For Linear Programming, Goh Saito

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Simplex pivoting algorithms remain the dominant approach to solve linear programming (LP) because they have advantages over interior-point methods. However, current simplex algorithms are often inadequate for solving a large-scale LPs because of their insufficient computational speeds. This dissertation develops the significantly faster simplex-based, active-set approaches called Constraint Optimal Selection Techniques (COSTs). COSTs specify a constraint-ordering rule based on constraints' likelihood of being binding at optimality, as well as a rule for adding constraints. In particular, new techniques for adding multiple constraints in an active-set framework, and an efficient constraint-ordering rule for LP are proposed. These innovations greatly reduce computation …

Design, Calibration And Testing Of A Force Balance For A Hypersonic Shock Tunnel, Pravin Vadassery

Mechanical and Aerospace Engineering Theses - Archive

The forces acting on a flight vehicle are critical for determining its performance. Of particular interest is the hypersonic regime. Force measurements are much more complex in hypersonic flows, where those speeds are simulated in shock tunnels. A force balance for such facilities contains sensitive gages that measure stress waves and ultimately determine the different components of force acting on the model. An external force balance was designed and fabricated for the UTA Hypersonic shock tunnel to measure drag at Mach 10. Static and dynamic calibrations were performed to find the transfer function of the system. Forces were recovered using …

Guidance And Control Of Unmanned Airships For Waypoint Navigation In The Presence Of Wind, Ghassan M. Atmeh

Mechanical and Aerospace Engineering Theses - Archive

Airships are a specific class of Lighter-Than-Air (LTA) vehicles. These vehicles achieve lift mainly through buoyancy; the usually ellipsoidal shaped hull contains a lifting gas such as helium, which produces the required lift though air displacement. Due to this method of operation an airship has the ability to conduct low-power hover, which makes it ideal for applications requiring hovering over long periods of time such as surveillance, terrain mapping, meteorology and GPS. In such applications the conventional fixed wing unmanned aircraft is less suitable. The work presented in this thesis deals with designing a controller that is capable of navigating …

Heat Transfer Enhancement In A Rectangular Channel Using Vortex Generator In A Laminar Flow, Ninad C. Maniar

Mechanical and Aerospace Engineering Theses - Archive

Enhancement of heat transfer through various means has been an intense area of research for many years. There are numerous applications where high performance heat exchange is desired. The cooling of electronics, such as microprocessors, is one example. The recent rise in the studies of heat exchange enhancement techniques has also lead to efficient and compact heat exchangers. This research involves the numerical analysis of heat exchange enhancement in a rectangular channel using different types of longitudinal vortex generators (LVG) for a laminar flow. A computational fluid dynamics software package was used to compute the 3-D steady viscous flows with …

Cfd Analysis Of Direct Evaporative Cooling Zone Of Air-Side Economizer For Containerized Data Center, Niket Shah

Mechanical and Aerospace Engineering Theses - Archive

Conventional data centers are extremely large buildings that have complex power distribution and cooling systems. These traditional brick and mortar data centers employ relatively expensive cooling systems and are inefficient. It has in turn led to an increase in construction and operational costs. Jonathan Koomey, Ph.D. of Lawrence Berkeley National Laboratory estimated that worldwide data center power consumption was 152.5 Billion kWh in 2005. In 2007, the US EPA estimated that servers and data centers, “consumed about 61 billion kilowatt-hours (kWh) in 2006 (1.5 percent of total U.S. electricity consumption) for a total electricity cost of about $4.5 billion. These …

Should Electrical Apprentices Study More Mathematics, David Lalor

Conference papers

The Department of Electrical Services Engineering, formerly known as the Installation Department, Kevin St., train Electrical Apprentices to become Qualified Electricians, has recently started to award Degrees in Electrical Services Engineering which includes the built environment. These students come from CAO applicants and from phase 6 students who have passed through the school. It is a popular and well subscribed course. I am involved in teach Phase 4 and 6. To progress to phase 6, phase 4 students must pass four examinations of which Electric Science is by all accounts the most difficult. To qualify as Electricians phase 6 also …

The Role Of Mathematics In Engineering Practice And In The Formation Of Engineers, Eileen Goold Dr, F. Devitt

Conference papers

I n Ireland, the number of school leavers pursuing professional engineering careers has been declining almost continuously over twenty years. Students wishing to pursue professional engineering degree courses are required to demonstrate proficiency in secondary school mathematics at the higher level. Yet, only a 16% minority of secondary school mathematics students in Ireland takes the Leaving Certificate mathematics exam at the higher level. It is widely thought that mathematics is the “key academic hurdle” in producing a supply of engineering graduates.

Cell Permeabilization And Inhibition Of Voltage-Gated Ca²+ And Na+ Channel Currents By Nanosecond Pulsed Electric Fields, Vasyl Nesin, Angela M. Bowman, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Previous studies have found that nanosecond pulsed electric field (nsPEF) exposure causes long-term permeabilization of the cell plasma membrane. In this study, we utilized the whole-cell patch-clamp method to study the nsPEF effect on currents of voltage-gated (VG) Ca²⁺ and Na⁺ channels (I_Ca and I_Na) in cultured GH3 and NG108 cells. We found that a single 300 or 600 ns pulse at or above 1.5-2 kV/cm caused prolonged inhibition of I_Ca and I_Na. Concurrently, nsPEF increased a non-inactivating leak current (I_leak), presumably due to the formation of nanoelectropores or larger …

Performance Of Prestressed Concrete Cylinder Pipe (Pccp) In Water Applilcations, Rahul Manda

Civil Engineering Theses - Archive

The analysis of water pipes failure data is of great importance as it has a significant impact society and the environment. These failures also have the overall impact on the financial burden on the water industry. This thesis evaluates the failure rate of Prestressed Concrete Cylinder Pipe (PCCP), which is one of the most conventional rigid pipes and are extensively used as the water and wastewater pipeline in the US and around the world. A statistical analysis of the failure rate based on the diameter size over multiple years will help in determining the performance of PCCP pipes. Also, the …

Effects Of Fiber Reinforced Polymer (Frp) Wrap On Reducing Chloride Penetration In Concrete, Gunther G. Garcia

Civil Engineering Theses - Archive

The objective of this study was to investigate the effects of FRP wrap on reducing chloride penetration in concrete. It has been established that FRP wrap used to retrofit concrete structures offer a high resistance to chemical solutions. The ACI 318-11 Code allows for a reduction of clear cover depth if an equivalent clear cover depth can be establish. The FRP material used herein consisted of Tyfo SCH-41 and Tyfo SEH-51A composites fabricated from carbon and glass fibers, respectively. The wrapped FRP concrete specimens and control specimens without FRP wrap were tested according to ASTM C 1543 and ASTM C …

Determining The Effectiveness Of Chlorine-Based Biofilm Control On The Friction Factors Of Large Diameter Pipelines In Raw Water, Shelly Stamler Hattan

Civil Engineering Theses - Archive

Large diameter transmission mains pumping raw water experience capacity loss during the summer months due to the growth of biofilm. The loss of capacity impacts power costs at a time when power is obtained at a premium. Biofilm growth varies with the seasons and varies along the length of the pipeline. Biofilm growth and decay directly impacts the friction factors. Future design work should consider a seasonal friction factor rather than an aged friction factor over time.The method of controlling biofilm is with the application of chloramines at the lake pump stations. This study compares the difference between little to …

Water Permeability In Fiber Reinforced Plastic (Fpr)-Wrapped Concrete, Jyoti Ojha

Civil Engineering Theses - Archive

A finite element analysis is performed using ANSYS software to analyze progress of water and its circulation in FRP wrapped concrete. This paper presents the modeling of water diffusion in FRP. Finite element programs do not usually employ issue permeability or diffusion. Therefore, diffusion of water in FRP is modeled by analogy with thermal conduction. A brief description of theoretical background is presented in the paper. The recommended FE modeling procedures are listed. Diffusion coefficient of Tyfo SCH 41S-1 obtained from an inspection report is used to analyze water permeably of FRP. Tyfo SCH 41S-1 is the most popular FRP …

Resilient Moduli Properties Of Compacted Unsaturated Subgrade Materials, Pinit Ruttanaporamakul

Civil Engineering Theses - Archive

According to the new Mechanistic Empirical Pavement Design Guide (MEPDG) and 1993 AASHTO flexible pavement design guide, Resilient Modulus (MR) has been used extensively as an important material property in structure design of pavement. The modulus is used as the primary input parameter to determine the stiffness parameters and constitutive behavior of pavement components. The system of pavement basically consists of the layers of surface, base, subbase (optional), and subgrade. The compacted subgrade soils supporting pavement structure are typically unsaturated with degrees of saturation varying from 75 to 90%. The effect of unsaturated soil behavior on the mechanical properties of …

Productivity Analysis Of Box Jacking, Hossein Tavakoli

Civil Engineering Theses - Archive

Trenchless Technology (TT) offers methods to install utilities through the ground without damaging the surface. Box Jacking is a trenchless method for installation of prefabricated box and drainage structures without digging a trench. The concept of box jacking is similar to pipe jacking operations by first excavating an entry shaft, building the thrust block and concrete base, and setting jacking equipment. The process starts with pushing boxes while excavating at face, however, the movement of each box is achieved each time excavation at the shield is completed. Additionally, a pilot tube might be required in advance of box jacking operations. …

Assessment And Rating Of Mechanically Stabilized Earth Walls, Noel Janacek

Civil Engineering Theses - Archive

Mechanically stabilized earth (MSE) walls have been increasingly utilized in the United States since 1972 and in Texas since 1979. MSE walls provide earth retention for commercial, industrial and transportation projects throughout Texas. Within the transportation industry, the traditional design life of MSE walls is 75 years, with new projects requiring 100 year design life. The millions of square feet of existing MSE walls are generally less than half of the anticipated design life, making identifying and assessing the existing wall inventory a significant asset management component for optimizing maintenance expenditures. This thesis proposes and applies a system that assesses …

Resilient Properties Of Unsaturated Base Materials, Ranjan Kumar Rout

Civil Engineering Theses - Archive

A pavement system basically consists of a surface layer, a base course, a subbase (optional) and the subgrade. As per MEPDG and 1993 AASHTO flexible pavement design guide Resilient Modulus (MR) is used as the primary input parameter to determine the stiffness parameters and the constitutive behavior of pavement components, such as subgrade and unbound bases. Generally, pavements are constructed on compacted soils that are typically unsaturated with degrees of saturation varying from 75 to 90%. The main focus of this research is to determine the effect of matric suction on the resilient moduli property of the base materials. The …

Design Of Controlled Low Strength Material For Bedding And Backfilling Using High Plasticity Clay, Anil Kumar Raavi

Civil Engineering Theses - Archive

Flowable fill or Controlled Low Strength Material (CLSM) is a self-compacted cementitious material used in the field in the place of compacted fill. It is also known as unshrinkable fill, controlled density fill, flowable mortar, plastic-soil cement, soil-cement slurry, and others. The advantages of this material include lesser soil settlements, elimination of compaction, and lower costs when compared to chemically treated and compacted subsoils. CLSMs have a wide range of applications such as using them as a backfill, bedding material, trench filling material, void filling material, bridge abutment and embankment materials and also in pavement bases. Current research is aimed …

Selecting A Shaft/Pit Construction Method For Trenchless Technology, Bassam Abusad

Civil Engineering Theses - Archive

The word shaft describes a vertical access point that is created by excavating, vertical boring, or blasting required before the start of tunneling or boring operations. Most trenchless technologies require entry shafts and exit shafts and in some cases and intermediate shaft Trenchless technologies are methods used for the construction and rehabilitation of underground utility pipes. Since pits and shafts are excavated below the ground surface level, Occupational Safety and Health Administration (OSHA) rules and regulations are enforced for the safety of the workers. The focus of this research is to describe shaft and pit construction methods as applied to …

Comparison Of Measured And Predicted Response Of Six Mnroad Asphalt Test Sections, Veni Valli Nagarajan

Civil Engineering Theses - Archive

The study, sponsored by MnRoad, aimed to compare the measured and predicted values of strains and stresses for six cells 33, 34, 35, 77, 78 and 79 of the third MnRoad experiments. Cells 33, 34 and 35 were constructed for studying the polyphosphoric acid study while cells 77, 78 and 79 for the fly-ash stabilization study, during 2007. Each cell is instrumented with three transverse strain gauges and three longitudinal strain gauges at the bottom of HMA layer while three pressure cells were located at the top of the subgrade layer to measure vertical compressive stress.The FWD deflection data collected …

Variance In Fade-Time Of A Gamma-Gamma Distributed Irradiance Signal, Troy T. Leclerc

Electronic Theses and Dissertations

Free-space optical communications are predominantly hindered by optical turbulence, an effect caused by temperature and pressure variations within the atmosphere. The result is an optical wave interfering with itself due to multipath propagation via tiny refractive-index fluctuations across the wave-front. Optical communication systems are affected when the channel conditions induce fading in the irradiance signal that is received at the detector. The nature of optical interference imparted by the atmosphere is a random process and therefore the received irradiance signal is often characterized by an appropriate probability density function (PDF). Data collected during past free-space optical experiments in the atmosphere …

Financial Evaluation Of Milege Based User Fees For Florida's Transportation Funding, Massoud Moradi

Electronic Theses and Dissertations

Motor fuel taxes have been collected as a principal source of highway funding for close to a century. They account for approximately two thirds of all the highway user fees and about half of all highway expenditures. Federal fuel taxes have not kept pace with the inflation in general and increasing traffic demand and resulting construction, maintenance and operation costs of the transportation assets in particular. Lack of political will, combined with rising anti-tax sentiment among the populace, has kept the federal tax level not only well below its initial intents, but also at a unsustainable level in future. Mileage …

Program And Proceedings: Nebraska Academy Of Sciences 1880–2012, 132nd Anniversary Year, One Hundred-Twenty-Second Annual Meeting

Nebraska Academy of Sciences: Programs and Proceedings

Program

Applied Science and Technology

Biological and Medical Sciences

Nebraska Wesleyan University Health and Sciences Graduate School Fair

Aeronautics and Space Science, Poster Session

Maiben Memorial Lecture: "The Status of Nebraska's Native Aspen," "Buffalo" Bruce McIntosh, Western Nebraska Resources Council

Aeronautics

Anthropology

Biological and Medical Sciences

Chemistry and Physics

Collegiate Academy: Biology

Collegiate Academy: Chemistry and Physics

Earth Science

History/Philosophy of Science

Junior Academy, Senior High Competition

Teaching of Science and Math

Junior Academy, Junior High Competition