Engineering Commons^™

Development Of A Vibration-Powered Impact Recorder, William Contreras

Theses

Currently, the U.S. Army stores a great deal of equipment for long periods of time. Often, this equipment is subjected to damaging vibrations. Given this, the army wants to be able to monitor the vibrations that are undergone by this equipment. Here, a battery-powered monitoring device would be undesirable because its batteries would need to be replaced. To solve this problem, an energy harvesting, vibration monitoring device has been developed. The device, which is known as a vibration-powered impact recorder (VPIR for short), uses a piezoelectric transducer to power a microcontroller, which uses the power to count the number of …

Use Of Fluorescent Micropsheres To Measure Coronary Flow Reserve In Rat Animal Model, Riddhi Harsh Shah

Theses

Heart attacks result from reduced or blocked blood flow through major coronary arteries, resulting in permanent damage to heart muscle. Coronary blood flow (CBF) is thus important to measure in experimental animal models of heart disease. A standard method to measure CBF uses tracer microspheres (Ø = 15 µm) injected into the left ventricle that flow through coronary arteries but cannot pass through capillaries and so become trapped in heart muscle. Previously, radioactive or colored microspheres have quantified the number of tracers trapped in the muscle. Fluorescent microspheres offer a more recent and more sensitive measurement mode. However, fluorescent microspheres …

Orthogonal Space Time Coding For Im/Dd Optical Wireless Communication With Single Carrier Frequency Domain Equalization, Nan Wu

Theses

Recently the development of optical wireless communication has received growing attention because of its unlimited bandwidth and simple implementation as compared to radio frequency communication application for indoor wireless data transmission. The objective of this thesis is to improve the performance of intensity-modulated direct- detection (IM/DD) optical wireless communications with single carrier frequency domain equalization (SCFDE) by using Orthogonal Space Time Code (OSTC). More attention has been paid to three SCFDE schemes due to their outstanding performances in practical cases. It is demonstrated that OSTC can be modified to be suitable to optical systems and provide an excellent enhancement to …

Influence Of Rear Wheel Tire Type On Wheelchair Propulsion Biomechanics, Mathew Yarossi

Theses

The objective of this study was to determine how rear wheel tire type affects wheelchair propulsion mechanics. Four persons with paraplegia and four persons with tetraplegia propelled their own wheelchairs on a roller system at self-selected speed using five different pairs of tires. Upper limb and trunk kinematics, perceived exertion, stroke pattern and the temporal characteristics of propulsion were measured. When using pneumatic (air filled) tires, with lower rolling resistance, participants had lower push frequency (p < .05), higher self selected speed (p < .05), less perceived exertion, less shoulder internal rotation, and a longer push stroke than when using solid, high rolling resistance tires. As rolling resistance increased, participants experienced negative changes in propulsion characteristic that contradicted current clinical practice guidelines for upper limb preservation following spinal cord injury. In addition, kinematics with solid, high rolling resistance tires were similar to those described during uphill or over carpet propulsion. In order to avoid unnecessary strain on the upper limbs and unwanted changes in propulsion biomechanics, wheelchair users, clinicians, and researchers should consider the use of lower rolling resistance, pneumatic rear tires.

Dissolution Testing Of Prednisone And Salicylic Acid Calibrator Tablets At Different Tablet Locations, Anandhavalavan Arulmozhi

Theses

Dissolution testing is routinely carried out in the pharmaceutical industry to determine the rate of dissolution of solid dosage forms. This test is one of the several tests that pharmaceutical companies typically conduct on oral dosage formulations (e.g., tablets) to determine compliance. The USP Dissolution Testing Apparatus 2 is the most common of the apparatuses listed in the USP. However, it has been shown previously that the dissolution profile of a tablet undergoing dissolution in the USP Dissolution Apparatus 2 can be affected by the tablet location in the apparatus.

In this work, the dissolution rates of both non-disintegrating tablets …

Digital Image Forensics, Fei Long

Theses

Digital image forensics is a relatively new research field that aims to expose the origin and composition of, and the history of processing applied to digital images. Hence, the digital image forensics is expected to be of significant importance to our modern society in which the digital media are getting more and more popular. In this thesis, image tampering detection and classification of double JPEG compression are the two major subjects studied. Since any manipulation applied to digital images changes image statistics, identifying statistical artifacts becomes critically important in image forensics. In this thesis, a few typical forensic techniques have …

Dissolution Of Disintegrating Solid Dosage Forms In A Modified Dissolution Testing Apparatus 2, Shrutiben Rameshbhai Parekh

Theses

Dissolution tests are routinely carried out in the pharmaceutical industry to determine the dissolution rate of solid dosage forms. Dissolution testing serves as a surrogate for drug bioavailability through in vitro–in vivo correlation (IVIVR), and it additionally helps in guiding the development of new formulations and in assessing lot-to-lot consistency, thus ensuring product quality. The United States Pharmacopoeia (USP) Dissolution Testing Apparatus 2 is the device most commonly used for this purpose. Despite its widespread use, dissolution testing using this apparatus remains susceptible to significant error and test failures. There is documented evidence that this apparatus is sensitive to several …

Transdermal And Transbuccal Delivery Of Lidocaine And Nicotine : Combined Effects Of Iontophoresis And Chemical Enhancers, Ran Wei

Theses

This study focused on the effects of iontophoresis and chemical enhancers on drug release. The transport of Lidocaine HCl (LHCl) and Nicotine Hydrogen Tartrate (NHT) through the skin and mucosa was evaluated for potential clinical applications. These two potential delivery routes have the advantage of avoiding first-pass effect. Samples were pretreated with enhancer solutions for one hour before the experiments. Passive or 0.3 mA iontophoresis-assisted drug diffusion was conducted for 8 hours to monitor the cumulative amount of drug released. Graphical methods and mathematical optimization techniques were implemented to analyze the data. The effects of chemical enhancers on the delivery …

Design And Evaluation Of An Adaptable Vector Coprocessor For Multicores, Timothy William Steele

Theses

Future applications for multi-core processor systems will require increased signal processing power along with increased resource utilization and decreased power consumption. Conservative power consumption will be of paramount importance primarily for battery-powered portable multi-core platforms (e.g., advanced cell phones, tablet computers, etc.). This thesis investigates the robustness, efficiency and effectiveness of vector coprocessor sharing policies in multi-core environments. Vector coprocessor sharing is based on an innovative design for a vector lane that forms the building block for the creation of larger vector coprocessors. This innovative lane design contains a floating-point multiply unit, a floating-point add/subtract unit, a miscellaneous function unit, …

Thermochemical Properties, Bond Energies And Internal Rotor Potentials In Methyl Ethyl Sulfide And Oxygenated Sulfur Hydrocarbons Intermediates For Modeling Its Combustion And Atmospheric Chemistry, Guanghui Song

Theses

Small (1 to 4 carbon) hydrocarbon sulfides and thiols are formed in the biosphere by microorganisms and subsequently emitted into the lithosphere, hydrosphere and atmosphere. In the atmosphere they are oxidized by photochemical and radical reactions to intermediate hydrocarbon and to sulfur oxides. The oxides of these sulfur compounds and the intermediates from the oxidation process are known to form aerosols that can counteract the global warming green house effect. Recent studies also suggest that some aerosols can also contribute to global warming. Sulfur oxides are also major contributors to acid rain as the results of the atmospheric chemistry oxidation …

The Effect Of Dynamic Standing On The Bone Mineral Density Of Non-Ambulatory Children: A Pilot Study, Megan Diane Damcott

Theses

In recent decades, research in osteoporosis has expanded to include the effects of prolonged immobilization on the load-bearing bones of non-ambulatory children. One current therapeutic intervention for this population is a passive standing program, in which the body is fully supported and continuous, stationary loading is applied to the bones, leading to the legs being primarily inactive. This research focused upon the effect of passive standing and a new therapeutic intervention of dynamic standing, a standing therapy in which the body is supported but vertical, reciprocal displacements which mimic the walking gait are applied to the feet, causing the muscles …

Investigation Of The Potential Catalytic Activities Of Several Metal Organic Framework (Mof) Materials, Guangyu Zhang

Theses

Metal-organic frameworks (MOFs) are promising porous materials due to their high porosities, large apparent surface areas, tunable pore properties and selective uptake of small molecules. Many researches have been focused on developing new MOF structures and exploring their use in gas storage and separation. Only few studies investigated the catalytic properties of MOFs. In this study, catalytic properties are explored over several MOFs including zeolitic imidazolate framework-8 (ZIF-8), Ni(FA) and Zn(FA). These MOFs are used as catalyst supports for iron or platinum nanoparticles. The catalysts are prepared using incipient wetness impregnation method and characterized with Brunauer-Emmett-Teller (BET), pulse chemisorption, X-ray …

A Microfluidic Culture For Two Populations Of Dorsal Root Ganglia For Differential Staining, Ishnoor Sidhu

Theses

The goal of this study was to design and fabricate a microfluidic system that can be used to visibly distinguish the two populations of dorsal root ganglia (DRGs) by differential staining. Polydimethylsiloxane (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its wide spread use in microfluidics. Various methods have been employed to pump fluids in these channels for applications ranging from patterning of cells and biomolecules to control of local environment factors such as temperature, which requires external pumping or other applied forces. We demonstrated a pump-free device that exploits the surface energy stored …

Effects Of Hypertension And Aging On Vascular Smooth Muscle Cell Contribution To Reconstituted Aortic Tissue Stiffness, Nancy Lisa Sehgel

Theses

Aortic stiffness increases with hypertension and aging, and much of this increase has been thought to occur due to changes in the extracellular matrix. However, an increase in cell stiffness could also be important. To study the cellular contribution to aortic stiffness, a reconstituted aortic tissue model (composed of vascular smooth muscle cells (VSMCs) in a collagen matrix) was developed. VSMCs isolated from thoracic aortic samples of 5-week and 18-week old male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were passaged four times and then separately incubated in collagen for two days on a cylindrical mandrel. The resulting …

Non-Invasive Interventions Top Reduce Low Back Dysfunction, Nadi Atalla

Theses

This study aims to quantitatively evaluate the low back condition so that low back dysfunction can be identified and classified when measurements show a variance from the normal. The evaluation is done by using the hysteresis concept. In this study, subjects received two different types of treatment: massaging using a mechanical massager for ten minutes and manual massaging by a professional physician. Using the Automated Anatomic Torsion Monitor (A-ATM), the low back of the subject was evaluated before and after treatment. The change in Hysteresis Loop Area (HLA) was -12.5% for mechanical massaging and -15.7% for manual massaging. The negative …

Design And Fabrication Of A Tapped Densification Apparatus For Bulk Solids, Joshua H. De Jong

Theses

Experiments are commonly used to ascertain the flow properties of bulk solids. One such property is a measurement quantity known as the tapped density. Here, a container of granular material is subjected to a long sequence of discrete taps, after which the bulk density - the total mass divided by the volume occupied –- is determined. Current technology exists to achieve the maximum tap density by subjecting a container to a user defined number of taps at a specific, predetermined amplitude and frequency. However, the final bulk density is known to be dependent on the tap parameters. It can therefore …

Study Of Controlled Release Of Dapsone From Modified Montmorillonite And Polymer Matrices, Jia Fan

Theses

This thesis focuses on the controlled release system of Dapsone (DAP) as the Active Pharmaceutical Ingredient (API) intercalated into sodium montmorillonite (MMT-Na+) and their combination with an anionic copolymer (Eudragit® S100). The effects of the excipients on the API dissolution rate were studied from their release profile in simulated intestinal fluid (pH=7.4) at 37±0.5°C. In the first part of the research, ionizable Dapsone was intercalated in the interlayers of MMT-Na+ to produce a nanohybrid. In the second part of the research, the nanohybrid was melt dispersed in the polymer to produce ternary (API/ Clay/ Polymer) composites. For comparison, API-polymer solid …

Emg-Based Determination Of Upper Extremity Virtual Trajectory, Akshata Anand Korgaonkar

Theses

Movement and position of the limbs of the human body are controlled by the interaction between the muscle and the peripheral and central nervous system. This interaction is nothing but the neural signals. Neural signals are electrical in nature and referred as action potentials. An EMG is a summation of action potentials from the muscle fibers under the electrode placed on the skin. Thus it is easy to estimate the nature and timing of the movement from the firing of an EMG signal. Kai Chen in his dissertation has built the model to represent the arm movement with stiffness, damping, …

Modeling Next Generation Air Traffic Control System With Petri Net, Hang Wu

Theses

The Federal Aviation Administration (FAA) is one of the largest Air Navigation Service Providers, managing air traffic for more than 15% of the world's airspace. Today's Air Traffic Control (ATC) system cannot meet the growth of the air traffic activities, which brings with more unprecedented delays. At the same time, Air Traffic Controllers are facing higher workload than ever before. The FAA has declared that the existing ATC system will transition to a new system known as “Free Flight”. “Free Flight” will change today's ATC system by giving pilots increased flexibility to choose and modify their routes in real time, …

Motor Planning For Reach Memorization Task In 3d Space, Atul Narkhede

Theses

Arm reaching towards remembered targets in three-dimensional space was analyzed. The aim of the project was to test whether various amounts of visual feedback, in combination with constant forces applied to the arm during reaching would affect the magnitude and direction of the reaching errors. The robotic arm (Haptic Master, Moog Inc) recorded the spatial position of the pointer attached to its end effector, thus tracking the movement of the subject's arm. Three haptically rendered targets at different points in space were presented to the subjects using stereo virtual environment. The simulation was programmed using Visual C++ and OpenGL. Eight …

Tilt Simulation : Virtual Reality Based Upper Extremity Stroke Rehabilitation, Harish Damodaran

Theses

The primary objective of this research is to design a recreational rehabilitation videogame that interactively encourages purposeful upper extremity gross motor movements. The simulation is also capable of continuous game modification to fit changing therapy goals, to match the needs of the players, and to provide continued motivation while capturing the interactive repetition. This thesis explains the design and features of this latest simulation - Tilt. Tilt uses physics to develop an engaging training experience and provides a realistic approach to virtual reality simulation including friction, elasticity and collisions between objects. It is designed to train upper extremity function as …

Energy Scavenging System For Indoor Wireless Sensor Network, David Andrew Crea

Theses

As wireless communication evolves wireless sensors have begun to be integrated into society more and more. As these sensors are used to a greater extent newer and better ways to keep them working optimally have begun to surface. One such method aims to further the sensors energy independence on humans. This technique is known as energy scavenging. The logic behind energy scavenging is to allow the device to have its own reliable source of energy that does not require upkeep, has a long life expectancy, and does not completely rely on an internal power source. The aim of this thesis …

Development Of A Centrifugal Microfluidic Device For Separation And Sorting In Biological Fluids, Gaurav Sunil Bagwe

Theses

A wide interest in employing micron-scale, integrated biochemical analysis systems for economical and rapid diagnosis has been the principal motivation behind this project. Low operating costs, portability and fast diagnosis times make centrifugal microfluidic devices an attractive option in patient-side diagnostics. Some essential tasks to be performed in microfluidic devices are sample-reagent transport, mixing, separation and detection. All these tasks require precise control of the RPM and spinning time. Centrifugal micro-fluidic platforms have been successfully implemented for detection of hepatitis A, tetanus, as well as for measurement of haemoglobin and hematocrit, for DNA analysis, and for assessment of cardiac disease …

Neurorehabilitation Of The Hand Using The Cybergrasp[Tm] And Mirror Image, Amy Frances Boos

Theses

In recent years, researchers have explored the use of a mirror image as a means of rehabilitation for individuals suffering from hemiparesis. Through neuroimaging and functional testing, neurological improvement has been demonstrated in those that engage in mirror therapy. Bilateral training, or simultaneous movement of both sides of the body, has also been studied as a treatment method to improve function after cerebral vascular accident. The development of robotic systems to assist movement of the human body has played a major role in the fabrication of bilateral training devices.

In this experiment, the CyberGrasp™ robotic exoskeleton was used to assist …