Engineering Commons^™

Investigation Of Solid Polymeric Hollow Fiber Heat Exchange Devices For Use In Thermally-Driven Desalination Processes, Saskia Christian

Theses

The heat exchange between hot brine (4 wt% NaCl) and cold water as well as between condensing steam and cold water without direct fluid-fluid contact using modules made out of solid polymeric hollow fibers of polypropylene (PP) and polyetheretherketone (PEEK) has been studied. The solid hollow fiber dimensions were 425μm/575μm (ID/OD) for PP and 420μm/570μm (ID/OD) for PEEK. Extensive heat transfer measurements have been performed and the experimentally-determined overall heat transfer coefficients utilized to isolate the wall heat transfer coefficient, the inside heat transfer coefficient and the outside heat transfer coefficient. The heat exchange between hot brine and cold water …

An Analytical Model Of Mac Protocol Dependant Power Consumption In Multi-Hop Ad Hoc Wireless Sensor Networks, Komlan Egoh

Theses

Power efficiency is the most constraining requirement for viable operation of battery-powered networked sensors. Conventionally, dynamic power management (DPM) is used to put sensor nodes into different states such as active, idle, and sleep, each consuming a certain level of power. Within the active state, communication operational states, such as receive and transmit consume different levels of nodal power. This thesis shows how DPM states and protocol operational states can be combined into a single stochastic model to finely evaluate the power consumption performance of a medium access control (MAC) protocol. The model is formulated as a semi-Markov decision process …

Evaluation Of Coding Scheme For Mimo Radar, Suresh Kumar Harikrishnan

Theses

Multiple Input Multiple Output (MIMO) antenna systems have shown a great potential for wireless communication. These systems support high capacity, increased diversity and interference suppression. Recently it has been proposed MIMO constellations for Radar. MIMO Radar is not only a new research field, but also a very promising approach in terms of overcoming Radar Cross Section (RCS) fluctuations with diversity. This thesis explores the potential of coding schemes for MIMO Radar.

The ambiguity functions measures related to MIMO Radar are used to evaluate how much diversity gain can be coherently achieved with certain coding schemes. The results of this analysis …

Multifractal Analysis Of Heart Rate Variability Using Wavelet-Transform Modulus-Maxima Method, Chirag Jani

Theses

Physiological signals are complex and carry information of human health. Recent studies reveal that under normal conditions, the heart rate time series shows multifractal behavior. In contrast, HRV in the pathological state such as congestive heart failure exhibits more monofractal-like structure. Recent advances in the assessment of heart rate variability (HRV) uses a nonlinear dynamics approach. In this study, the main objective is to use the wavelet-transform modulus-maxima method for the multifractal analysis of the heart rate time senes.

The degree of the multifractality is defined by the singularities (a point in time series where a mathematical function is not …

In Vitro Evaluation Of Human Mesenchymal Stem Cell Neural Differentiation On Tyrsine-Derived Polyarylates And Polycarbonates, Yee-Shuan Lee

Theses

Present spinal cord injury treatments cannot restore motor and sensory functions caused by the injury. These functions can return in the hopes of repairing the neural cells with a tissue engineered designed scaffold complex. The scaffold complex will include cells to repair and replace the damaged cells.

Mesenchymal stem cells (MSC) are multipotent adult stem ells that are capable of differentiating along several lineage pathways. Neural stem cell and MSC differentiating along the neural lineage bave been investigated both in vivo and in vitro depicting its feasibility. MSC for neural differentiation can be achieved by microenvironmental signaling. Substrate surface characteristics …

Automated Liquid Dispensing Pin For Dna Microarray Applications, Suganya Parthasarathy

Theses

This thesis describes the research and development of a new liquid dispensing/aspiring system that is capable of producing micro sized spots/droplets for molecular biology research and analysis. In particular, the application is focused on DNA microarray fabrication with the goals of smaller spot size, higher yield, more efficient usage of biological materials, and capability to handle high viscosity liquids. The new system is based on active sensing and control and it is part of a fully integrated robotic microarray system for genomic and proteomic applications. The prototype system handles water as well as thick liquids such as 100% glycerol and …

Synthesis And Characterization Of Polymer Nanocomposites, Nirav S. Patel

Theses

Polymer nanocomposites were produced by solution mixing of a commercial flexible acrylic polymer paint, with nanofillers of different size, shape, aspect ratio and purity such as hydrotalcite (HT), sodium montmorillonite (MMT), single wall carbon nanotubes (SWNT) and fullerenes (FUL), at 5 and 10 wt% loading. Structural characteristics and mechanical, thermal and barrier properties of the nanocomposites were characterized by different techniques and compared to those of the unfilled polymer.

The presence of partially exfoliated and intercalated nanoplatelets in the polymer resulted in increased 2% secant tensile modulus, and decreased tensile strength and elongation at break, to different extents. While the …

Wet-Spinning And Thermal Analysis Of Collagen Fibers Incorporating Hydroxyapatite In Mixed And Coated Form, Sandesh Nathaniel Prakash

Theses

The composition of natural bone comprises of collagen (Cg) as organic phase which acts as a matrix and inorganic calcium phosphate, particularly hydroxyapatite (HA), which is used as reinforcement. This study involved the wet-spinning of collagen fibers incorporating HA in mixed and coated form. The weight percent ratio of collagen and HA in the composite fibers was 95 to 5 respectively. HA coating on pure collagen fibers was achieved by immersing them in HA solution formed by mixing HA in water. With Thermomechanical analysis, the highest breaking point temperature was obtained for the composite fibers and the least with pure …

Quantification Of Long-Range Power Law Correlations Among Healthy And Pathologic Subjects Using Detrended Fluctuation Analysis And Multifractal Detrended Fluctuation Analysis, Hardick Raval

Theses

The healthy heartbeat is traditionally thought to be regulated according to the classical principle of homeostasis whereby physiologic systems operate to reduce variability and achieve an equilibrium-like state. However recent studies reveal that under normal conditions, beat-to-beat fluctuation in heart rate display the kind of long-range correlations typically exhibited by the dynamical system far away from equilibrium. In contrast, heart rate time series from patients with severe congestive heart failure show a breakdown of this long-range correlation behavior. Two different non-linear dynamic methods namely Detrended Fluctuation Analysis (DFA) and Multifractal (MF) DFA are used for the quantification of this correlation …

The Creation And Testing Of A Mock Functional Magnetic Resonance Imaging Facility For Pain Patients, Gladstone Vincent Reid

Theses

Unfamiliarity with functional Magnetic Resonance Imaging (fMRI) facilities leads to unwanted stress-related disturbances in the processing of fMRI data. A mock fMRI facility was developed to increase familiarization among subjects participating in fiviRI studies and to alleviate the time and cost of familiarizing each subject in an actual fMRI facility. A decommissioned Magnetic Resonance Imaging (MRI) unit was remodeled to visually and aurally resemble the Siemens Magnetom Allegra 3 Telsa fMRI machine currently used at the University of Medicine and Dentistry of New Jersey (UMDNJ), Newark, New Jersey. Instrumentation was developed using LabVIEW software which presented subjects with recreated sounds …

Quantification Of Regularity In Rr-Interval Time Series Using Approximate Entropy, Sample Entropy, And Multi-Scale Entropy, Nirvish Shah

Theses

Heart rate variability (HRV) has proven to be a useful noninvasive tool to study the neuronal control of the heart. Recently, nonlinear dynamic methods based on chaos theory and fractal dynamics have been developed to uncover the nonlinear fluctuations in heart rate. Approximate Entropy (ApEn), Sample Entropy (SampEn) and Multi-scale Entropy (MSE) are measures based on chaos theory that quantify the regularity in time series. This study has been designed to examine the ability of these measures to distinguish the RR-interval time series of normal subjects (NSR) from subjects with congestive heart failure (CHF). The study was conducted on the …

A Multi-Factor Model For Evaluating Manufacturing Defect Opportunities In Six Sigma Analysis, Karthikeyan Sundaram

Theses

Six Sigma Quality Analysis provides a structured method for manufacturing quality problems and defect opportunities to be defined, measured, analyzed, improved, and controlled. The technique is now being widely used in both the manufacturing and service industries to evaluate the classical "defects per million" metric. An underlying assumption of classical Six Sigma Analysis is that all defects contribute equally to the derivation of the defect rate. In the thesis, it is proposed that this assumption skews and often distorts the derived defect rate. Using classical Six Sigma the user is able to list a large number of often border-line defect …

Multicodes For Improved Range Resolution In Radar, Rhiya Vitto

Theses

Third generation (3G) wireless systems are required to support a variety of communication services like voice, image, motion picture transmission, etc, each of which requires different transmission rates. Multi-code modulation has been introduced therefore as a means of supporting multi-rate services and operating in multi-cell environments [8, 9, 10]. This multi-rate multi-function capability may be used in Radar related applications, too. For example, a single transmitted waveform consisting of two orthogonal codes can be used to simultaneously track a target and obtain high range resolution. Tracking requires low bandwidth and high resolution needs a high bandwidth signal. Orthogonal codes like …

Combined Effects Of Prozac And Hypothalmic Mediated Response On Masseter Muscle Activity In The Cat, Chika P. Nwaorgu

Theses

The present study tested the hypothesis that infusion of Prozac would serve to suppress defensive rage elicited from the medial hypothalamus of the cat. Cats are known to exhibit certain kind of behavior, known as the "defensive rage response" such as unsheathing of the claws, retraction of the ear and vocalization (hissing).

Three adult cats (2 males and 1 female) weighing (2.8 - 3.4 kg) were utilized during the experiments. Cannula-electrodes were implanted into the medial hypothalamus for elicitation of defensive rage behavior. EMG activity was recorded with a bipolar electrode attached to the masseter muscle to establish baseline before …

A Gait Generation Mechanism For Leg Rehabilitation Therapy, Yazan Ahmad Manna

Theses

While most take their ability to walk for granted, some are unable to walk secondary to any number of pathologies, such as traumatic brain injury (TBI), spinal cord injury (SCI), cerebrovascular accidents (CVA), cerebral palsy (CP), multiple sclerosis (MS), Parkinson's disease, as well as various orthopedic conditions. Decreased activity has been shown to be associated with rapidly deconditioning and other co-morbidities. Rehabilitation techniques that afford patients the ability to begin reconditioning through walking sooner may ultimately enhance their return to a better quality of life.

The overall goal of this study is to design a gait generation mechanism for rehabilitation …

Haptic Induced Motor Learning And The Extension Of Its Benefits To Stroke Patients, Adrienne M. Coppa

Theses

In this research, the Haptic Master robotic arm and virtual environments are used to induce motor learning in subjects with no known musculoskeletal or neurological disorders. It is found in this research that both perception and performance of the subject are increased through the haptic and visual feedback delivered through the Haptic Master. These system benefits may be extended to enhance therapies for patients with loss of motor skills due to neurological disease or brain injury.

Force and visual feedback were manipulated within virtual environment scenarios to facilitate learning. In one force feedback condition, the subject is required to maneuver …

Growth Behavior Of Fibroblasts Influenced By Small Changes In Polymer Structure, Saraswathi Doddi

Theses

Polymers are a promising class of biomaterials that can be engineered to meet specific end use requirements. The order and processing history of the polymer, which would alter the molecular orientation of the material could have a significant contribution towards cellular attachment and in turn, cell growth on the particular polymer. Surface properties of the material were considered to directly influence the properties of the adherent cells including cellular growth and reorganization. The present study is aimed at comparing cell growth on polyarylates with that of polylactic acid in their original state or by introducing small changes in the surface …

Enhancing End-To-End Quality Of Service Provisioning In Wireless Ad Hoc Networks Using Service Vectors, Didem Gozupek

Theses

A cross-layer architecture that achieves significant power savings, while enhancing the end-to-end QoS provisioning and granularity in wireless ad hoc networks is proposed in this thesis. Recently, a new concept called service vector has been introduced, which enables an end host to choose different service classes along its data path. This scheme enhances the user benefits from the network services and network resource utilization, while maintaining the simplicity and scalability of the current Differentiated Services (DiffServ) network architecture. This thesis explores the application of this concept on wireless ad hoc networks and provides a cross-layer architecture based on the combination …

Deposition Of Tantalum Thin Films By Rf Sputtering With Substrate Bias, Savita Raina

Theses

The effects of energetic ion bombardment on the crystallographic structure of RF sputtered tantalum thin films on different substrates, particularly aluminum and silicon, have been studied. The effect of substrate biasing on ion current and film thickness has been investigated. The study included comparison between substrate ion current of DC sputtering and RF sputtering and also was aimed at finding the process parameters, which could influence the crystallographic phase of Ta film. The characterization of Ta films is carried by RBS and x-ray diffraction techniques.

A magnetron sputtering system with a matching network between the source and the RF generator …

A Study On The Thermal Degradation Resistance Of Thermoplastic Polyurethane Coatings, Montaser Mohamed Zamzam

Theses

In this work, a comprehensive study of thermoplastic polyurethanes (TPUs) and the influence of the hard block content on their performance was carried out. The study comprises an extensive literature survey of the chemistry, structure and properties, and degradation and stability of TPUs, an experimental section dedicated to the materials, methodologies and instrumentations involved in the execution of the study, and a results and discussion section detailing all the findings and interpretation of the investigation.

TPU elastomers were prepared from 4,4’-diphenyimethane diisocyanate (MDI), monoethylene glycol (MEG), triethylene diamine (Dabco EG), Coim G-211 poly(ester) diol using the ‘one shot’ melt polymerization …

Stereo Vision Algorithm Using Propagation Of Correspondences Along An Array Of Cameras, Danyan Ganjali

Theses

One well known problem in stereo vision is the trade-off between precision and accuracy.

In a conventional two camera model, as the baseline separating the two cameras becomes smaller, the images that both cameras produce become more identical. This results in a more accurate set of correspondences, however at the same time causing less precise depth measurement due to the small angle used for triangulation. Similarly, in a larger baseline model, the depth measurement is more precise while the correspondences are not as accurate as of the shorter baseline model. This thesis proposes a method that promises to solve the …

Evaluation Of Unifac Group Interaction Parameters Usijng Properties Based On Quantum Mechanical Calculations, Hansan Kim

Theses

Current group-contribution methods such as ASOG and UNIFAC are widely used for approximate estimation of mixture behavior but unable to distinguish between isomers. Atoms in Molecules (AIM) theory can solve these problems by using quantum mechanics and computational chemistry to compute atomic contributions to molecular properties and to intermolecular interactions. Rigorously defined properties available through AIM theory and new functional group definitions are used for the UNIFAC model to predict the behavior of various mixtures. Results are presented for various mixtures with nine regressed global parameters to optimize model's predictive capability. The results are also compared to analogous results for …

Ambulatory Biopotential Measurement, Lakshmi Chitra Penugonda

Theses

Biopotential signals measure the electrical activity of different parts of the body. Conventional bedside monitors only provide information about the body under restricted conditions. Observation and documentation of biopotential signal during daily activities and the relation to patient symptoms may be important factors for clinical decision-making. Ambulatory monitoring helps to monitor the biopotential signal of a patient in the natural environment. The effective ambulatory system can help a physician to diagnose the patient's abnormality.

In this project, a low cost and flexible ambulatory biopotential system, compared to the commercially available systems, was designed and tested. Concurrently a software program was …

Planar Visual Fusion Scintigraphy, Jacob Puthiamadathil

Theses

Planar scintigraphy, while providing useful information about the distribution of the radiopharmaceutical being used, often does not provide adequate information about the surrounding anatomical structures. A proposed method to solve this problem is by registering and fusing a scintigraphic image with a digital visual image. Fusing planar scintigraphic images with visual photographic images to supply an anatomic correlate to regions of radiopharmaceutical accumulation has been explored in this study. The digital visual image will provide a context for the relevant structures in the scintigraphic image. The validity of using one set of affine transformation parameters for registering all patient data …

Evaluation Of Knox Group Contribution Parameters Using Quantum Based Molecular And Group Properties, Myriam Carrillo

Theses

Thermodynamic property prediction through the group contribution methods has been improving. However, the approaches considered in the past present not only limitations on the physical basis but often have restrictions as to certain substances, such as isomers. A new group contribution method is proposed that uses AIM theory, which is based on computational chemistry and quantum mechanics, to overcome these limitations by treating each molecule individually. An evaluation of this method as applied to the Knox model is proposed and analyzed for Vapor Liquid Equilibrium (VLE) of mixtures with the help of nine global parameters that are obtained by correlation. …

Non-Linear Digital Control Of A Mckibben Muscle System, Surinkumar Patel

Theses

McKibben muscles are pneumatic actuators that have potential application in the rehabilitation of persons with physical impairments. These actuators have been known to exhibit similarities in human musculoskeletal systems. In order to better understand and improve the closed - loop control of these pneumatic muscles, a physical joint model was constructed with an agonist and an antagonist muscle operating under non-linear control. With the use of LabVIEW software, compliant McKibben air muscles and Flock-of-Birds sensor, the author was able to implement and compare a standard bang-bang controller and experimental non-linear digital Proportional (P) controller. The feedback mechanism is based on …

Enabling Cost Aware Routing With Auctions In Wireless Ad-Hoc Networks, Ali Yuksel

Theses

Battery power is a precious resource in wireless ad-hoc networks, and most routing protocols that have been proposed so far do not generate cost efficient routes. In this thesis, a novel auction-based cost-aware routing scheme, called CARA, is presented. CARA is designed as an extension of the MAC layer, and is shown to improve the cost efficiency of existing ad-hoc routing protocols through dynamic power control, while introducing only minimal additional overhead. The MAC layer at each node is given the capability to run local sealed-bid second-price auctions for the user data packets that need to be transmitted, and to …

Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya

Theses

A wireless ad-hoc network is a cooperative communication network deployed with a specific purpose. It is characterized by dynamically changing topology with no fixed infrastructure which exhibits a perfectly vulnerable state for a number of different kinds of attacks.

This thesis proposes a novel technique of achieving security in wireless mobile ad hoc networks by integrating a simple clustering and a voting mechanism together. The purpose of forming a cluster is to facilitate security in the network and the voting is performed to support the decision making process in the cluster. A procedure of forming small homogenous clusters throughout the …

Relationship Between The Autonomic Nervous System And The Recovering Heart Post Exercise Using Heart Rate Variability, Pierre Asselin

Theses

The goal of this thesis is to determine if a relationship exists between the activity of the autonomic nervous system (ANS) and the speed of heart rate recovery post maximal exercise. The parasympathetic branch of the ANS was assessed during rest by obtaining the high frequency (HF) component of the heart rate variability (HRV) frequency spectrum. The recovery time was estimated by fitting an exponential curve to the heart rate post exercise where the exponent was used to calculate the time constant to indicate recovery time. A regression was then performed on the HF and recovery time in order to …

On Performance Analysis Of Optimal Diversity Combining With Imperfect Channel Estimation, Yong Peng

Theses

The optimal diversity combining technique is investigated for multipath Rayleigh and Ricean fading channel with additive white Gaussian noise where only imperfect channel knowledge is available at the receiver. The non-observable estimation error contributes as an additive source of noise which is not white. Therefore, the optimal combining weight is derived taking into consideration the imperfect channel knowledge.

The bit error rate for BPSK modulation over correlated Rayleigh and Ricean fading channel is derived for minimum mean square channel estimation using pilot symbol assisted modulation. Analytical result and Monte-Carlo simulation are presented for specific channel and estimation models to demonstrate …