Engineering Commons^™

Extending The Boundary Method For Solving Human Motion Problems Using A 3 Dimensional Coupled Pendulum Model, Avani Janardan Patel

Theses

Mathematical modeling, an evolving area in movement analysis research, couples quantitative measures of human motion with theoretical concepts in physiology and mechanics. Literature reveals two methods to solve for human motion problems, Forward and Inverse Mechanics. In this investigation, a new approach called the Boundaty Method is adopted to solve for human motion. This approach has the advantage of being able to solve for both new motions and the net muscular joint forces required to produce those motions but only at those discrete times and body configurations that are believed to be most crucial for accomplishing the task.

The method …

Simulation Analysis Of Anti-Rollover Mechanism For Vehicles, Mohib L. Raid

Theses

Rollover accidents are considered the most significant safety problems for all classes of light vehicles, especially pickups, Sport Utility Vehicles (SUV), Light Truck Vehicle (LTV) and vans. The main objective of the research is the design of a new mechanism able to keep the vehicle stable under various road conditions and high speeds, to prevent the vehicle from rolling over and to maintain the stability for the vehicle by creating an anti-rolling torque on the vehicle body capable of turning the vehicle smoothly to stable position.

Evaluation Of Effect Of Extrusion Process Variables On Mechanical Properties Of Extruded Collagen Tubes And Effect Of Post Extrusion Treatments, Mayank K. Patel

Theses

This study evaluated the effect of extrusion process variable on mechanical properties of extruded collagen tubes made using a specialized extruder, made by ZOKO Corporation of Czechoslovakia. Three extrusion variables were considered; extrusion speed, linear draw rate and rotation speed. Using Taguchi L₄ matrix, a design of experiment (DOE) was run. Two mechanical properties, wall thickness and estimated elastic modulus, were considered as response of this DOE. Data was analyzed statically to evaluate the effect of extrusion variables on both these properties. Result of this study showed that linear draw rate of the extrusion process has the highest influence …

Fabrication Of Nanofiber Scaffolds By Electrospinning And It's Potential For Tissue Engineering, Shobana Shanmugasundaram

Theses

Electrospinning is a fabrication process that uses an electric field to control the deposition of polymer fibers on to a target substrate. This electrospinning strategy can be used to fabricate fibrous polymer mats composed of fiber diameters ranging from several microns down to tens of nanometers. This study assesses the potential of electrospinning, as an alternative scaffold fabrication technique for tissue engineering applications. In this study, electrospinning is adapted to produce tissue-engineering scaffolds of two different size ranges composed of non-woven poly-L-lactide (PLLA) nanofibers and as a first study, the potential use of these scaffolds as tissue engineering scaffolds was …

Si-Sio2 Interface Behavior In N-Mosfets With Screening Potential During High-Field Injection, Purushothaman Srinivasan

Theses

This work investigates the screening of hot carrier stress degradation in n-channel MOSFETs when the devices were exposed to plasma processing. Devices with various antenna ratios were subjected to current stress (both gate injection and substrate injection) while the source and drain terminals were reverse biased by a screening potential followed by hot carrier stress. It was observed that screening of the drain edge was effective for both gate injection and substrate injection at different screening potentials. The hot carrier lifetime is directly related to interface state density (Dit), measured by charge pumping method. The results suggest that hot electron …

Particle Size Dependence On Immobilized Molecular Sensors : Assay Of Nucleic Acid Probes Attached To Paramagnetic Particles, Celin Sunny

Theses

Nanotechnology is concerned with materials and systems whose structure and components exhibit novel and significantly improved physical, chemical and biological properties, phenomena and processes due to their nano scale size.

The transition from micro scale to nano scale leads to a number of changes in physical properties, possibly including new physical principles, some of which may be yet to be discovered. One of the major factors in this is the increase in ratio of surface area to volume.

This thesis research uses the increase in ratio of surface area to volume property of going from macro to micro to nano …

Spinning Of Collagen Fibers And Characterizing Thermal, Mechanical, Tensile And Structural Properties, Grace Evangelin Tatagiri

Theses

Collagen is the most important building block in the entire animal world. It plays an important role in regeneration of broken bones and wound healing, also helps grow blood vessels to feed the healing areas. The use of synthetic materials has been extensive, but these materials have there own limits and drawbacks. Poor biocompatibility of these materials is the main issue and often result in inflammations. Hence collagen is being heralded as one of the most appropriate replacement as an implantable material. The reasons being that it is a naturally occurring material, exhibits high biocompatibility low antigenicity and host response. …

Human Factors Approach Towards Improving Readability Of Bus Schedules, Anand Tharanathan

Theses

Due to an increasing concern over the readability of existing bus schedules of a public transportation agency the schedule format was redesigned. Two prototype schedules were designed based on the gathered information from the literature survey, focus group meetings and data from other public transportation agencies' schedules. One of the prototypes was designed by giving primary importance to the direction of travel and was named the directional prototype schedule. The other prototype was designed by giving primary importance to the day of the week, and was named weekday / weekend prototype schedule. A time based laboratory experiment and a subjective …

A Statistical Ultra Wideband Indoor Channel Model And The Effects Of Antenna Directivity On Multipath Delay Spread And Path Loss In Ultra Wideband Indoor Channels, Jason Anthony Dabin

Theses

Ultra-wideband (UWB) indoor frequency domain channel measurements have been performed in the 2 GHz to 6 GHz frequency band using three different transmitter/receiver (Tx/Rx) antenna combination pairs. The effects of antenna directivity on path loss and multipath propagation in the channel were analyzed extensively for various omni-directional and directional antenna combinations. A statistical model of the path loss in the channel is presented, where the parameters in the model (i.e., path loss exponent and shadow fading statistics) are dependent on the particular Tx/Rx antenna combination. Time domain statistics of the channel (i.e., mean delay spread and RMS delay spread) are …

A Kinematic Analysis Of Hand Configurations In Static And Dynamic Fingerspelling, Gillian B. Sherry

Theses

The focus of this study was the investigation of target handshapes in American Sign Language fingerspelling in order to determine whether there was a difference between static canonical structures and structures produced in the context of a movement sequence. This was achieved by measuring the joint angles of a signing hand with an 18-sensor CyberGlove® by Virtual Technologies, Inc.

A discriminant analysis was used to identify targets that occurred at points of minimum angular joint velocity. A multivariate analysis of variance with planned compansons was then applied to these dynamic data along with the static data to test the hypothesis. …

Supply Chain Risk Analysis, Venkata R. Kallepalli

Theses

A new decision support system is proposed and developed that will help sustaining business in a high-risk business environment. The system is developed as a web application to better integrate the supply chain entities and to provide a common platform for performing risk analysis in a supply chain. The system performs a risk analysis and calculates risk factor with each activity in the supply considering its interrelationship with other activities. Bayesian networks along with fault tree structures are embedded in the system and logical rules are used to perform a qualitative fault tree analysis, as the data required to calculate …

Parametric Synthesis Of Sign Language, Jerome Allen

Theses

The isolation of the deaf community from mainstream society is in part due to the lack of knowledge most hearing people have of sign language. To most, there seems to be little need to learn a language that is spoken by such a small minority unless perhaps a relative is unable to hear. Even with a desire to learn, the task may seem insurmountable due to the unique formational and grammatical rules of the language.

This linguistic rift has led to the call for an automatic translation system with the ability to take voice or written text as input and …

Design And Implementation Of Heart Rate Variability Measures In The Time Domain, Binoy John Mathews

Theses

The following study was conducted to design and implement computer programs to derive five time domain and two frequency domain Heart Rate Variability (HRV) measures from 24 hour Holter monitor recordings and to generate activity plots that display the variation of three of the five time domain measures and two frequency domain measures over a period of 24 hours.

Working with known pre and post experimental ECG data taken from a cyclical exercise program, standard parameters in both the time and frequency domains were derived using programs designed in Labview 7.0 engineering software package. Five parameters in the time domain …

An Investigation Of Position And Force During Gait-Mimicking Finger Motions, Matthew Stephen Noesner

Theses

Spinal cord injuries are extremely debilitating, often leaving the injured person without the ability to use their legs (paraplegia) and sometimes, without the ability to use their arms and legs (tetraplegia or quadriplegia). Currently, primitive forms of feed-forward functional electrical stimulation (FES) and special orthotics are available for persons with paraplegia. However, these forms of FES do not allow the individual to actually control their movements on a real-time basis, nor do they offer the ability for the injured person to sense the ground on which they stand.

It is the goal of the researchers at the Neuromuscular Engineering Laboratory, …

Supply Chain Risk Mitigation, Roshan R. Pai

Theses

In recent years, especially post 9/11, there has been an increasing awareness for securing business supply chains against probable disruptions. With globalization and lean inventories, the efficiency of supply chain has greatly enhanced over the years, but at the expense of new vulnerabilities. Supply chain vulnerabilities have resulted in disruptions to the economic stability and security. As a result, risk analysis and mitigation has now grown to become one of the key links to business stabilization. To ensure business continuity, it is necessary to identify key assets (physical and operational) within the supply chain and secure them against probable threats. …

Extrusion And Evaluation Of Degradation Rate And Porosity Of Small Diameter Collagen Tubes, Bipinkumar G. Patel

Theses

The limited availability of autografts and failure of small diameter synthetic vascular grafts has stimulated continuing efforts to develop small diameter vascular grafts based on natural materials. The small diameter collagen tubes were extruded using bovine collagen type I. The biodegradation rate was determined and compared for small diameter collagen tubes crosslinked with glutaraldehyde and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and Nhydroxysuccinimide (NHS) to evaluate physio-chemical properties. The samples were also evaluated for their surface area and porosity using mercury porosimeter. The noncrosslinked tubes almost completely degraded after 2 hours. The tubes crosslinked with EDC/NHS degraded slower than the ones crosslinked with …

Biomimetic Sensor For In-Vivo Applications, Daya I. Sooryadas

Theses

The development of sensitive specific devices (e.g., molecular sensors) for the detection, diagnosis and monitoring of diseases, drug discovery, environmental detection of pollutants and/or biological agents has been an active area of research. A molecular sensor is a biomolecule or biomimetic molecule that performs two distinct functions in detecting target molecules. The sensor molecule recognizes a target molecule and specifically binds to it. This specific binding generates a signal in response to the event of target binding that can be then detected. The long term vision of this thesis research work is to develop a specific recognition ligand for detecting …

Adaptive Learning For Event Modeling And Pattern Classification, Shuangshuang Dai

Dissertations

It is crucial to detect, characterize and model events of interest in a new propulsion system. As technology advances, the amount of data being generated increases significantly with respect to time. This increase substantially strains our ability to interpret the data at an equivalent rate. It demands efficient methodologies and algorithms in the development of automated event modeling and pattern recognition to detect and characterize events of interest and correlate them to the system performance. The fact that the information required to properly evaluate system performance and health is seldom known in advance further exacerbates this issue.

Event modeling and …

A Micromachined Thermo-Optical Light Modulator Based On Semiconductor-To-Metal Phase Transition, Lijun Jiang

Dissertations

In this research, a micromachined thermo-optical light modulator was realized based on the semiconductor-to-metal phase transition of vanadium dioxide (VO₂) thin film. VO₂ undergoes a reversible phase transition at approximately 68 0C, which is accompanied with drastic changes in its electrical and optical properties. The sharp electrical resistivity change can be as great as five orders. Optically, VO₂ film will switch from a transparent semiconductor phase to a reflective metal phase upon the phase transition. The light modulator in this research exploits this phase transition related optical switching by using surface micromachined low-thermal-mass pixels to achieve …

Intercity Travel Demand : A Utility-Consistent Simultaneous Trip Generation And Mode Choice Model, Guilin Li

Dissertations

An intercity travel decision includes a complex set of subdecisions, such as when to travel, where to travel, which mode to choose, and others. The main focus of this dissertation is to examine trip frequency and mode choice of intercity non-business travel.

The objective of this study is to understand intercity travel behavior using disaggregate models. The proposed conceptual framework for intercity travel behavior leads to a nested logit/continuous choice model that is rigorously linked to the utility maximization theory. Compared to a traditional intercity travel demand model, the proposed model is utility consistent in that trip generation and mode …

Effect Of Fullerene Containing Lubricants On Wear Resistance Of Machine Components In Boundary Lubrication, Andriy Titov

Dissertations

Fullerenes, a new form of carbon nanomaterials, possess unique physical and mechanical properties that make their use as additives to liquid lubricants potentially beneficial. The goal of this study was to investigate the effect of fullerene containing lubricants on wear resistance of steel-bronze couples operating under boundary lubrication conditions. A mathematical model of deformed asperity contact was built to calculate real contact area and real contact pressure. Computer controlled wear friction testing methodology and equipment were designed, developed and implemented for obtaining reliable and objective experimental data. In addition, optical and scanning electron microscopy and standard surface texture analysis were …

Migration Of An Intruder Particle In A Boundary Driven Shear Flow, Jian Liu

Dissertations

This study reports on three-dimensional, discrete element simulations of a single large spherical intruder in a Couette shear flow composed of uniform sized particles. The simulation results are useful in providing a numerical reproduction of the experiments for size segregation and mixing. This in turn has a major importance in many industries which are concerned with handling of particles and powders, such as pharmaceutical manufacturing, agriculture, chemical and mineral processing.

Discrete element simulations are carried out using the "soft sphere" model of Walton, et. al., which provides a method for obtaining the information at a macroscopic level from multi-body collisions …

Reactive Modification Of Polyesters And Their Blends, Chen Wan

Dissertations

As part of a broader research effort to investigate the chemical modification of polyesters by reactive processing a low molecular weight (MW) unsaturated polyester (UP) and a higher MW saturated polyester, polyethylene terephthalate (PET), alone or blended with polypropylene (PP) were melt processed in a batch mixer and continuous twin screw extruders. Modification was monitored by on-line rheology and the products were characterized primarily by off-line rheology, morphology and thermal analysis. Efforts were made to establish processing/property relationships and provide an insight of the accompanying structural changes. The overall response of the reactively modified systems was found to be strongly …

Oblivious Data Hiding : A Practical Approach, Husrev T. Sencar

Dissertations

This dissertation presents an in-depth study of oblivious data hiding with the emphasis on quantization based schemes. Three main issues are specifically addressed:

1. Theoretical and practical aspects of embedder-detector design.

2. Performance evaluation, and analysis of performance vs. complexity tradeoffs.

3. Some application specific implementations.

A communications framework based on channel adaptive encoding and channel independent decoding is proposed and interpreted in terms of oblivious data hiding problem. The duality between the suggested encoding-decoding scheme and practical embedding-detection schemes are examined. With this perspective, a formal treatment of the "processing" employed in quantization based hiding methods is presented. In …

Fabrication And Characterization Of Microcrystalline Silicon Solar Cells, Liwei Li

Dissertations

In this study, single junction p-i-n μc-Si:H solar cells were prepared using plasma of silane diluted by hydrogen in a low-cost, single chamber, non-load-locked RF-PECVD system. Direct structural characterization of μc-Si:H solar cells, rather than stand-alone films, was conducted using Raman Spectroscopy, XRD, and AFM. Strong correlations among device deposition, i-layer structural properties, and device performance have been established. With such correlations, critical issues in fabricating low-cost, large-scale, high performance μc-Si:H solar cells were identified.

The critical importance of seeding processes in determining the microstructure of μc-Si:H i-layers and performance of μc-Si:H solar cells has been demonstrated. Using …

Studies On Improved Integrated Membrane-Based Chromatographic Process For Bioseparation, Yanke Xu

Dissertations

To improve protein separation and purification directly from a fermentation broth, a novel membrane filtration-cum-chromatography device configuration having a relatively impermeable coated zone near the hollow fiber module outlet has been developed. The integrated membrane filtration-cum-chromatography unit packed with chromatographic beads on the shell side of the hollow fiber unit enjoys the advantages of both membrane filtration and chromatography; it allows one to load the chromatographic media directly from the fermentation broth or lysate and separate the adsorbed proteins through the subsequent elution step in a cyclic process.

Interfacial polymerization was carried out to coat the bottom section of the …

The Use Of A Water Quality Model To Evaluate The Impacts Of Combined Sewer Overflows On The Lower Hudson River, Wen-Pin Shu

Dissertations

CSO discharges have long been recognized as a significant source of water pollution. While many sources of water pollution have been controlled over the past 20 years, CSOs continue to be a main environmental concern in several areas, especially in old cities. In the past, most CSO research focused on the CSO control processes, including floatables and suspended solids removal. Few studies have been conducted in the area of the impacts of CSO discharge on the receiving water quality. To achieve this purpose, a powerful water-modeling tool, WASP 6.1, is utilized in this study. The Lower Hudson River is selected …

Vibration-Induced Densification Of Granule Materials, Ninghua Zhang

Dissertations

Physical experiments as well as discrete element simulations of vibration are carried out. The use of different amplitudes and frequencies are applied in the experiments to facilitate the observation of densification trends with mono-disperse acrylic spheres and multi-disperse polyethylene pellets. For mono-disperse acrylic spheres, four densification trends are found at different vibration conditions, and attaining the "maximum density" is closely related to the combination of vibration frequency and amplitude, in agreement with experiments in the literature. For multi-disperse polyethylene pellets, there is a substantial increase in solids fraction due to the effects of particle shape and surface friction. Computer simulations …

Multi-Spectral Light Interaction Modeling And Imaging Of Skin Lesions, Sachin Vidyanand Patwardhan

Dissertations

Nevoscope as a diagnostic tool for melanoma was evaluated using a white light source with promising results. Information about the lesion depth and its structure will further improve the sensitivity and specificity of melanoma diagnosis. Wavelength-dependent variable penetration power of monochromatic light in the trans-illumination imaging using the Nevoscope can be used to obtain this information. Optimal selection of wavelengths for multi-spectral imaging requires light-tissue interaction modeling. For this, three-dimensional wavelength dependent voxel-based models of skin lesions with different depths are proposed. A Monte Carlo simulation algorithm (MCSVL) is developed in MATLAB and the tissue models are simulated using the …

Ip-Based Virtual Private Networks And Proportional Quality Of Service Differentiation, Jingdi Zeng

Dissertations

IP-based virtual private networks (VPNs) have the potential of delivering cost-effective, secure, and private network-like services. Having surveyed current enabling techniques, an overall picture of IP VPN implementations is presented.

In order to provision the equivalent quality of service (QoS) of legacy connection-oriented layer 2 VPNs (e.g., Frame Relay and ATM), IP VPNs have to overcome the intrinsically best effort characteristics of the Internet. Subsequently, a hierarchical QoS guarantee framework for IP VPNs is proposed, stitching together development progresses from recent research and engineering work.

To differentiate IP VPN QoS, the proportional QoS differentiation model, whose QoS specification granularity compromises …