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Material Selection And Optimization To Mitigate 316l Stainless Steel Corrosion In A Condensate Stabilizer, Afif Saif Nasser Harhara Nov 2008

Material Selection And Optimization To Mitigate 316l Stainless Steel Corrosion In A Condensate Stabilizer, Afif Saif Nasser Harhara

Theses

The United Arab Emirates (UAE) is one of the key players of the oil and gas industry of the world; with oil reserves estimated at 9% of the total world reserves, the petroleum industry is considered to be the backbone of the economy.

In one of the gas processing facilities in Abu Dhabi, UAE; a case of material failure occurred in the fractionating column twice in a cycle of less than 2 years. The materials used for the internals of the column was stainless steel 316L. The different types of stainless steel corrosion were studied with emphasis on the suspected …


Optimum Non Hydrocarbon Gas Injection Development Process And Ultimate Recovery Maximization., Abdulla A.F. Abed Nov 2008

Optimum Non Hydrocarbon Gas Injection Development Process And Ultimate Recovery Maximization., Abdulla A.F. Abed

Theses

A multi layered heterogeneous reservoir was selected for this study. The integrated reservoir characterization model and the pertinent transformed reservoir simulation history matched model were quality assured and quality checked.

The development scheme was identified and selected where the pattern and completion of the wells were defined to fit the heterogeneity of the reservoir characterization model. Lateral and maximum block contact holes were investigated.

The development processes studied were mainly hydrogen sulphide, carbon dioxide, nitrogen and rich hydrocarbon gas. The Water Alternating Gas/ Simultaneous Water Alternating Gas (WAG/SWAG) processes were also assured. In addition to the main gas and WAG/SWAG …


Classification Of Hand Held Shapes And Locations In Continuous Signing, Swetha Karri Aug 2008

Classification Of Hand Held Shapes And Locations In Continuous Signing, Swetha Karri

Theses

Sign language for the deaf and hearing impaired replaces speech with manually produced signs. Each sign has been categorized as being combinations of handshape, movement, orientation, location, and facial expressions. Of the five sign parameters, this thesis focuses on classification of two of the main parameters, the hand shapes and locations, in continuous signing.

Since the nature of hand shapes is transient and not static, neural networks was used as a classifier for hand shapes. And since locations in sign language are defined by linguistic variables rather than by hard core position values, fuzzy logic was used as a classifier …


A Two Dimensional Model Of Magnetic Field Assisted Assembly, Gaurev Devrani Aug 2008

A Two Dimensional Model Of Magnetic Field Assisted Assembly, Gaurev Devrani

Theses

A simplified model to simulate the magnetic field distribution for applications in magnetic field assisted assembly of semiconductor device structures, using commercial software (Vizimag), has been implemented. Solenoids have been utilized to serve as electromagnets that are responsible for the assembly process. Magnetic shielding techniques have been deployed to isolate the influence of one solenoid over another. These solenoids are used to move the devices that need to be placed in recesses within the substrate. The bottom of the devices and the recesses are coated with magnetic materials to facilitate the movement and placement of devices within the recesses in …


Precipitation Of Ultrafine Particles Using Liquid Antisolvent With Concentric Ultrasonic Nozzle And Subcritical Co2, Satya Chaitanya Kunchala Aug 2008

Precipitation Of Ultrafine Particles Using Liquid Antisolvent With Concentric Ultrasonic Nozzle And Subcritical Co2, Satya Chaitanya Kunchala

Theses

Nanotechnology has become more relevant in the pharmaceutical industry. Almost 40% of the drugs developed by pharmaceutical industries are poorly soluble in water which limits the bioavailability of these drugs in body fluids. Hence, it is necessary to reduce the particle size, which increases the interfacial surface area. This work focuses on micronization of class ii drug Griseofulvin which is poorly water soluble. Two processes namely, liquid antisolvent precipitation using ultrasonic nozzle and other process using subcritical CO2 have been used to produce ultrafine particles of this drug.

In liquid antisolvent precipitation, a combination of ultrasound, polymer and surfactant …


Biomechanical Testing Of Upright Range Of Motion Versus Overhead Supine Range Of Motion, Linda Uko Aug 2008

Biomechanical Testing Of Upright Range Of Motion Versus Overhead Supine Range Of Motion, Linda Uko

Theses

Rehabilitation of an elbow, following injury, is not a well-studied subject. Clinically, there is not a general consensus on which recovery method is optimal for healing an unstable elbow. When dealing with medial collateral ligament deficiency, many authors have proposed several forearm positions that will yield proper healing of the unstable elbow. Some researchers believe that active mobilization of the elbow with the arm in a vertical position is a safe protocol for rehabilitation with the forearm oriented in a supine pronated position. It was also mentioned that the compressive forces due to the active mobilization of the arm will …


Experimental Investigation Of The Effect Of Sonication On The Precipitation Of Grieseofluvin By Impinging Jets, Ankit H. Patel Aug 2008

Experimental Investigation Of The Effect Of Sonication On The Precipitation Of Grieseofluvin By Impinging Jets, Ankit H. Patel

Theses

Almost 80% of drugs on the market are manufactured as solid dosage forms, such as tablets. Drug bioavailability increases as the particle size decreases and the surface area per unit volume of drug increases. Therefore, there is a keen interest by the pharmaceutical industry to develop techniques that can be used to manufacture particles of active pharmaceutical ingredients (API) in the nano/micro particle range. Impinging jets is one of the most promising techniques to do so.

In this work, a submerged impinging jet system coupled with an ultrasonic probe (sonicator) was used to precipitate Griseofulvin, a common, poorly water-soluble antifungal …


Photoplethysmorgraph-Derived Respiration, Priyanka Pankaj Shah Aug 2008

Photoplethysmorgraph-Derived Respiration, Priyanka Pankaj Shah

Theses

Stress & Motivated Behavioral Institute (SMBI) has developed a research program to provide an objective evaluation of the physiological and neurocognitive impact of human electromuscular muscular interference (HEMI) devices in humans. The initial step is to understand their physiological impact, which is characterized by vital signs. Volunteers are recruited from HEMI training programs with the provision that data collection can not interfere with training. Thus, an ambulatory system was assembled. There are two main issues in the current ambulatory system, one of which is the reliability of the respiration signal obtained using a strain gauge respiration band, mainly due to …


Dem Simulated Radial And Axial Pressure In A Cylindrical Granular Column, Meng Cui Aug 2008

Dem Simulated Radial And Axial Pressure In A Cylindrical Granular Column, Meng Cui

Theses

The study of packed beds of granular spheres and their applications are of great interest to industries, and one of the most important subjects that has been studied is cylindrical beds. In 1895, H. A. Janssen discovered that in a vertical cylinder the pressure measured at the bottom does not depend upon the height of the filling in contrast to Newtonian fluids that possess linear hydrostatic pressure equilibrium. One of assumptions of his theory stated that the horizontal pressure is proportional to the vertical. In this thesis, this physical hypothesis is investigated using Discrete Element Simulations of inelastic with a …


Design And Fabrication Of A Microneedle For The Implantation Of Floating Microstimulators, Faysal Ahmed Aug 2008

Design And Fabrication Of A Microneedle For The Implantation Of Floating Microstimulators, Faysal Ahmed

Theses

Neural prosthetics are used to stimulate any remaining functional nervous tissue in order to restore function in visual, auditory, or other physiological components associated with the nervous system. Microelectrodes have been used in stimulating and detecting electrical activity in neurons. When stimulating or recording neural tissue activity using microelectrodes, there are usually many problems and difficulties in obtaining the correct functionality and results. There is great difficulty in placing these microelectrodes in a specific location in the central nervous system due to various problems with the methodology used. Many different techniques such as the traditional interconnected microelectrodes have been an …


Design And Construction Of A Novel Transpalpebral Ophthalmic Tonometer, Philippe R. Moinot May 2008

Design And Construction Of A Novel Transpalpebral Ophthalmic Tonometer, Philippe R. Moinot

Theses

Glaucoma -- a degeneration of the optic nerve- is a leading cause of blindness which is primarily caused by large fluctuations in intraocular pressure (lOP) known as diurnal variations. Because these peak in the early morning dropping off rapidly, a self administrable and inexpensive lOP home testing procedure is highly desirable. The approach contained herein -- unlike traditional Goldman applanation tonometry which requires the use of ophthalmic anesthetics and complex diagnostic equipment- describes a novel lOP measurement method consisting of concavation of the cornea or sclera through the palpebra superior by the spherical tip of an optoelectronic photodetector suspended in …


Interactions Between Adult Human Mesenchymal Stem Cells And Nanofibrous Scaffolds Of Different Compositions, Lisamarie Moore May 2008

Interactions Between Adult Human Mesenchymal Stem Cells And Nanofibrous Scaffolds Of Different Compositions, Lisamarie Moore

Theses

Stem cells have become increasingly important in the biomedical field because they have the potential to invade and regenerate damaged tissue. In particular, the bone marrow contains meesenchymal stem cells (MSCs) that have the capacity to differentiate into many cell lineages. The incorporation of MSCs within a multidimensional biomaterial provides a delivery vehicle to areas of injury. Natural and synthetic biomaterials can be made into scaffolds to represent different types of tissues. The ratio of synthetic to natural biomaterials in the scaffold influences the interaction with MSCs. This thesis created two different nanofibrous scaffolds by a process of electrospinning. The …


Synthesis And Analysis Of Carbon Nanowalls And Their Raman Spectroscopy, Amit Mahajan May 2008

Synthesis And Analysis Of Carbon Nanowalls And Their Raman Spectroscopy, Amit Mahajan

Theses

Growth of Carbon Nanowalls has been carried out by Radio Frequency Chemical Vapor Deposition (RF-PECVD) on various substrates. Hydrogen was used as an active gas for the growth where as Ethanol bubbled with Argon was used as carbon source for formation of Carbon Nanowalls (CNW). The growth was then confinned by Raman Spectroscopy and Scanning Electron Microscope (SEM) images. Also the need of using catalyst in CNW has been analyzed. The intensities of D and G bands obtained from Raman spectrum have been related to the length of Graphene walls, to study the CNW's length on different substrates.

The growth …


A Comparative Study Of Common Crosslinking Agents For Electrospun Collagen Scaffolds, Pallavi Masih May 2008

A Comparative Study Of Common Crosslinking Agents For Electrospun Collagen Scaffolds, Pallavi Masih

Theses

Cartilage injury is one of the leading causes of knee pain in the world. Over two million Americans suffer from cartilage injury every year, resulting in swelling, pain or joint impairment, causing it difficult to maintain an active life style. Synthetic grafts are used extensively to restore tissue functions. The major drawback limiting successful incorporation of synthetic grafts in body is their lower ability to integrate to natural tissue, poor biocompatibility which often results in triggering immunogenic responses, causing graft rejection. Collagen is thus studied and used excessively as a successful implantable material. The reason being that it is natural …


Altered Brain Activity In Autistic Children Versus Healthy Controls While Performing Simple Tasks Using Fmri, Donald Martin Adams Jr. May 2008

Altered Brain Activity In Autistic Children Versus Healthy Controls While Performing Simple Tasks Using Fmri, Donald Martin Adams Jr.

Theses

Functional magnetic resonance imaging (fMRI) studies dealing with Autistic children have primarily been concerned with cognitive facial recognition. Recent studies have demonstrated that Autistic children, when compared to healthy matched controls, exhibit higher neuronal activity when identifying patterns or objects, but lower levels of activity in regards to facial recognition.

The objective of this study was to examine both facial and object recognition and compare them to simple sensorimotor tasks. All subjects were administered 5 stimuli each lasting 320 seconds. Subjects were instructed to use a button press box to identify between a Person/Object and an Arrow/Object. They were then …


Derivation Of The Respiratory Rate Signal From A Single Lead Ecg, Murtaza M. Lakdawala May 2008

Derivation Of The Respiratory Rate Signal From A Single Lead Ecg, Murtaza M. Lakdawala

Theses

It has been long established that respiration has an influence on heart rate, and this effect is called respiratory sinus arrhythmia. As a result, two inferences can be postulated: first respiration information can be derived from cardiac activity, and second this effect offers the potential of removing the respiration effect that suppresses cardiac information which is of clinical significance. As a result of research performed at NJIT, there is a significant amount of data on exercise and heart rate recovery, but not the associated respiration signal. The motivation of this research was to compare and implement an optimal ECG derived …


A Virtual Training Environment For Wheelchair Mounted Robot, Elizabeth Leichtnam May 2008

A Virtual Training Environment For Wheelchair Mounted Robot, Elizabeth Leichtnam

Theses

A model of a robotic manipulator designed to respond to different inputs from users with different skills or conditions is presented. This model can be adapted to different input variables and converted into joint angles which relate to movement in space of the manipulator's links. The algorithm allows for real time response and the features of the virtual environments (i.e., 3D design, stereoscopic vision) gives the designers the opportunity to use this model for training and usability evaluation according to the skills and different conditions that users could present.

Two types of virtual environments were created aiming to be used …


Automated Multi-Well Neural Injury Device, Linda Y. Chen May 2008

Automated Multi-Well Neural Injury Device, Linda Y. Chen

Theses

Traumatic Brain Injury (TBI) is a wide spread pathological problem occurring in 1.4 million individuals every year according to the National Institute of Neurological Disorders and Stroke. There are several types of TBI and the most prominent ones are concussion, contusion, hematoma, coup-contrecoup injury and diffuse axonal injury (DAI). The most severe type and the one that is the hardest to diagnose is DAI. DAI occurs mostly due to accidents relating to automobile, motorcycles and in some cases fall and assault, resulting in a "shearing" phenomenon of the brain. Patients with DAI can range from being, mildly injured, severely disabled …


Raman Scattering In Free Standing Porous Si Films, Thenappan Chidambaram May 2008

Raman Scattering In Free Standing Porous Si Films, Thenappan Chidambaram

Theses

In this thesis, Raman Scattering of free standing porous silicon on sapphire samples of controllably varying porosity is studied. The free standing, fully crystalline porous silicon films were prepared by electrochemical etching and the porous structure were lifted-off by a procedure based on electro-polishing. During Raman scattering measurements, the samples are exposed to relatively high intensity laser radiation. Free-standing porous Si sample temperature and thermal conductivity are calculated by comparing intensities of Stokes and anti-Stokes Raman peaks. Compared to crystalline Si, we find strong decrease in thermal conductivity accompanied by a change in the phonon spectra. Also, comparing Stokes and …


Thermal And Morphological Analysis Of Collagen-Plla Electrospun Blends, Angana Banerjee May 2008

Thermal And Morphological Analysis Of Collagen-Plla Electrospun Blends, Angana Banerjee

Theses

Electrospinning of bovine Type I collagen and Poly (L-lactic acid) produces blended nanofiber scaffolds that may have application in tissue engineering, wound dressing and drug delivery.

The goal of this research work was to produce and characterize blended nanofibers of a protein, collagen, and a synthetic polymer, poly (L-lactic acid). This study focuses on the in-depth analysis of the appearance of the structural relaxation occurring at the glass transition temperature of PLLA in the collagen-PLLA blended electrospun mats. It is speculated that occurrence of this thermal event is more prominent in PLLA with high molecular weight due to the presence …


Surface Recordings Of Evoked Field Potentials From The Cerebellum With A Flexmea Microelectrode Array, Jonathan David Groth May 2008

Surface Recordings Of Evoked Field Potentials From The Cerebellum With A Flexmea Microelectrode Array, Jonathan David Groth

Theses

The cerebellum is an integral part of multijoint control. There are two input pathways to the cerebellar cortex, the mossy fiber and the climbing fiber pathways. The mossy fiber pathway forms a disynaptic input to Purkinje cells through the granular cells. This disynaptic input produces a multicomponent field potential composed of the P1, N 1, N2, N3, N4, and P3 waves. The climbing fiber input forms a monosynaptic input to the Purkinje cells and thus creates a much simpler field potential.

The mossy and climbing fiber field potentials were recorded with a FlexMEA microelectrode array from the pial surface of …


Synthesis Of Corn-Derived Carbohydrate Derivatives As Effective Multifunctional Sunscreen, Xianhong Feng May 2008

Synthesis Of Corn-Derived Carbohydrate Derivatives As Effective Multifunctional Sunscreen, Xianhong Feng

Theses

The eighty-years-old sunscreen industry is sustained by the growing incidence of skin cancer and the continual exploration of skin aging. From the UVB-induced erythema to the UVA-induced persistent pigment darkening, scientists have used versatile methods to reveal that not only does UVB damage skin but also that longer wavelengths such as UVAIL (290nm ~ 340nm) and UVAL rays (340nm ~ 400nm) trigger skin cancer, premature skin aging and immunosuppression.

To meet a significant demand for improved photoprotection, a broad-spectrum sunscreen with a high extinction coefficient has been desired. As part of our ongoing studies on isosorbide-cinnamate derivatives, this work have …


Experimental Investigation Of The Fluid Velocity Distribution In Stirred Tank Reactors Equipped With Retreat-Blade Impellers Using Laser Doppler Velocimetry, Deepak Rajesh Madhrani May 2008

Experimental Investigation Of The Fluid Velocity Distribution In Stirred Tank Reactors Equipped With Retreat-Blade Impellers Using Laser Doppler Velocimetry, Deepak Rajesh Madhrani

Theses

Stirred tank reactors are commonly used in the pharmaceutical industry for synthesis of Active Pharmaceutical Ingredients (API's) and their intermediates. Typically, these vessels are glass-lined and are provided with a single retreat-blade glass-lined impeller and a single baffle. Despite their ubiquitous utilization in the pharmaceutical industry for at least the past 40 years, the mixing characteristics of these systems have not been studied to any great extent, making it difficult to predict mixing performance in any given operation.

In this work, the velocity distribution inside the typical glass-lined vessel/impeller system was experimentally quantified using Laser Doppler Velocimetry (LDV), which is …


The Synergistic Effect Of Pulsed Electromagnetic Fields And Demineralized Bone Matrix On The Osteogenic Differentiation Of Mesenchymal Stem Cells, John Manocchio May 2008

The Synergistic Effect Of Pulsed Electromagnetic Fields And Demineralized Bone Matrix On The Osteogenic Differentiation Of Mesenchymal Stem Cells, John Manocchio

Theses

Orthopaedic bone grafting continues to be a mainstay in the treatment of non unions and other difficult to heal bone defects. Tissue engineering strategies have focused on providing bone graft materials that are osteoconductive, osteoinductive and osteogenic in order to achieve optimal bone healing. Furthermore, electrical stimulation technologies such as pulsed electromagnetic fields (PEMF) have been used to enhance the effectiveness of bone graft materials. PEMP has been shown to have a synergistic effect with BMP-2 and it was hypothesized that PEMF would have the same effect with demineralized bone matrix (DBM). In the present study human mesenchymal stem cells …


Process-Structure-Property Relationships Of Resorbable Desamino Tyrosine Derived Polymers : Effect Of Backbone Chemistry And Assembly On Drug Delivery, Pinar Nebol May 2008

Process-Structure-Property Relationships Of Resorbable Desamino Tyrosine Derived Polymers : Effect Of Backbone Chemistry And Assembly On Drug Delivery, Pinar Nebol

Theses

The selection the correct biomaterial for a specific medical application plays an important role for the success of both application and the device. Since different applications require different properties, investigation and improvement of biomaterials with different properties are very important. L-tyrosine derived polymers enable the manipulation of the properties of the material by changing backbone or pendent chain structure. L-tyrosine derived polyarylate is one of the class of these materials.

This study investigates the behavior of the tyrosine derived polyarylates under in vitro conditions. The change of structure caused by incubation in phosphate buffer solution and the effect on the …


Effects Of Natural And Accelerated Weathering On The Performance Of Locally Manufactured Polymer-Modified Bituminous Waterproofing Membranes, Rauda Ali Saeed Al Saadi May 2008

Effects Of Natural And Accelerated Weathering On The Performance Of Locally Manufactured Polymer-Modified Bituminous Waterproofing Membranes, Rauda Ali Saeed Al Saadi

Theses

As in most industrial sectors, today there is a growing preoccupation about product quality. Since waterproofing systems are intended to have the longest possible service life, one of the most critical quality features is their aging performance. As a result, the importance of aging tests is steadily growing, especially in the hot-dry climate zones.

Polymer-modified bituminous waterproofing membranes are normally exposed to solar radiation and various weathering conditions when used in residential and commercial buildings. They are attacked and deteriorated to some degree by environmental factors such as heat, radiation, especially ultraviolet, moisture and gases. The weathering (aging) consequences commonly …


Finger Joint Impedance Control Applications To Investigate Spasticity, David Naisby Paglia Jan 2008

Finger Joint Impedance Control Applications To Investigate Spasticity, David Naisby Paglia

Theses

In order to investigate how spasticity disrupts the capabilities of the human body, a better understanding of how joint impedance control operates in healthy individuals is necessary. In this investigation, a second order rotary torque model was implemented to investigate the impedances at the metacarpophalangeal (MCP) joint of the index finger. The model was fit to approximately 25 milliseconds of force and displacement data to determine the mechanical impedances at the finger tip. Ranges of damping and stiffness were optimized over a range of mean finger tip force (0-12 N) for extension. The equilibrium-point hypothesis was examined when compared to …


Retransmission Strategies For Moving Networks Over Ricean Fading Channels, Alex Ruiz Lee Jan 2008

Retransmission Strategies For Moving Networks Over Ricean Fading Channels, Alex Ruiz Lee

Theses

The problem of designing retransmission protocols based on Hybrid Automatic Repeat reQuest (HARQ) for moving networks over Ricean fading channels has been considered. The scenario of interest consists of one receiver traveling at a given speed while connected to a wireless network based on OFDM (e.g., WiMax) through several base stations located along the path. Five different retransmission protocols that combine HARQ with handover between adjacent base stations are considered. Their performance in terms of number of retransmissions per packet via numerical simulations, considering both frequency selective and nonselective channels are presented. The results obtained show the relevant advantage that …


Kerberos Phone Secure Messenger, Nabeel Al-Saber Jan 2008

Kerberos Phone Secure Messenger, Nabeel Al-Saber

Theses

Security is becoming vital in today's open insecure Internet. While popular Internet enabled mobile devices are spreading widely, the security of such platforms is not maturely addressed. This research extends the popular Kerberos authentication protocol to run on mobile phones and builds a novel Kerberos Secure Phone Messenger (KSPM) on top of the protocol. Moreover, the Kerberos network authentication protocol provides user authentication and message privacy with the convenience of secret key cryptography. Such an advantage in mobile phones helps reduce the computational burden and power consumption if compared with public key cryptography. KSPM achieves high standards in terms of …


Fracture Healing : The Effects Of Local Insulin Delivery Via Calcium Sulfate And Tricalcium Phosphate, Sarah Elizabeth Buchala Jan 2008

Fracture Healing : The Effects Of Local Insulin Delivery Via Calcium Sulfate And Tricalcium Phosphate, Sarah Elizabeth Buchala

Theses

Previous studies have documented the major role played by insulin in osseous healing. This is the first study to examine local intramedullary insulin delivery to the fracture site and its effect upon the normal fracture healing process. Preceding results show that when administered at the fracture site of the impaired fracture healing model of the diabetic BB Wistar rat, insulin will regulate early cellular proliferation and chondrogenesis and late mineralized tissue, cartilage content and mechanical strength.

In this study, two novel delivery vehicles have been evaluated for sustained insulin release in the normal fracture model of the BB Wistar rat. …