Engineering Commons^™

Electrical Characterization Of High-K Gate Dielectrics For Advanced Cmos Gate Stacks, Yi Ming Ding

Dissertations

The oxide/substrate interface quality and the dielectric quality of metal oxide semiconductor (MOS) gate stack structures are critical to future CMOS technology. As SiO₂ was replaced by the high-k dielectric to further equivalent oxide thickness (EOT), high mobility substrates like Ge have attracted increasing in replacing Si substrate to further enhance devices performance. Precise control of the interface between high-k and the semiconductor substrate is the key of the high performance of future transistor. In this study, traditional electrical characterization methods are used on these novel MOS devices, prepared by advanced atomic layer deposition (ALD) process and with pre …

Processing Of Cds/Cdte Solar Cell And The Growth Model Of Cdte Thin Film, Guogen Liu

Dissertations

Cadmium telluride is the only thin film photovoltaic (PV) technology to surpass crystalline silicon PV in the cost. The most common CdTe solar cells consist of a simple p-n heterojunction structure containing a p-doped CdTe layer and n-doped cadmium sulfide (CdS) layer, which acts as a window layer. Cadmium Sulfide (CdS) thin films are often deposited on glass substrates coated with TCO layers by the close-spaced sublimation (CSS) or sputter techniques in industrial because of in-line production integration. It is seldom reported that CdS is deposited by the chemical bath deposition (CBD) batch process. The bottleneck of CBD for commercial …

A Multimodal Investigation In Eye Movements, Raj Jaswal

Dissertations

While functional magnetic resonance imaging (fMRI) has identified which regions of interest (ROIs) are functionally active during a vergence movement (inward or outward eye rotation), task-modulated coactivation between ROIs is less understood. This study tests the following hypotheses: (1) significant task-modulated coactivation would be observed between the frontal eye fields (FEFs), the posterior parietal cortex (PPC), and the cerebellar vermis (CV); (2) significantly more functional activity and task-modulated coactivation would be observed in binocularly normal controls (BNCs) compared with convergence insufficiency (CI) subjects; and (3) after vergence training, the functional activity and task-modulated coactivation would increase in CIs compared with …

Biomimetic And Vascularized 3-D Liver Cancer Model, Derek Yip

Dissertations

Anti-angiogenic drugs have failed to show significant extended mortality, except when co-administered with chemotherapy drugs in clinical trials. This should be predicted by in vitro models, and yet 2D in vitro models of liver cancer co-administered with these two types of drugs show increased cell viability, contradicting clinical trials. In vitro models should mimic clinical trials in order to accurately predict drug outcomes. 2D in vitro models fail because they lack features of the cancer environment such as presence of stromal cells and a vasculature.

In order to achieve a biomimetic and vascularized in vitro model that would better recapitulate …

Optimization Of Headway, Stops, And Time Points Considering Stochastic Bus Arrivals, Liuhui Zhao

Dissertations

With the capability to transport a large number of passengers, public transit acts as an important role in congestion reduction and energy conservation. However, the quality of transit service, in terms of accessibility and reliability, significantly affects model choices of transit users. Unreliable service will cause extra wait time to passengers because of headway irregularity at stops, as well as extra recovery time built into schedule and additional cost to operators because of ineffective utilization of allocated resources.

This study aims to optimize service planning and improve reliability for a fixed bus route, yielding maximum operator’s profit. Three models are …

Application Of Inkjet Printing Technology To Flexible Batteries, Yuan Gu

Dissertations

Printing technologies have been considered as alternative methods to fabricate thin films in recent years. More and more functional devices like resistors, sensors, antennas and even energy storage devices have been fabricated by printing technologies. As a typical digital printing technology, inkjet printing has much more advantages over the traditional mechanical printing technologies such as: low cost, computer controllable shape design and precise deposition. In this investigation, application of inkjet printing is used to fabricate conductive tracks and rechargeable lithium ion batteries.

Particle free silver ink is developed to solve this problem. In this research, silver complex solution is printed …

Fabrication Of 3d Hydrogel-Based Microscale Tissue Analog Chip With Integrated Optofluidics, Venkatakrishnan Rengarajan

Dissertations

Lab-on-a-chip (LOC) is a device that integrates one or more laboratory functions in a single chip with dimensions ranging from a micrometer to a few millimeters. On-chip optofluidics, which combines microfluidics and tunable micro-optical components, is crucial for bio-sensing applications. However, recently reported optofluidic devices have only two-dimensional (2D) dielectric or metallic regions for sensing cellular activity, which fail to mimic the three-dimensional (3D) in vivo microenvironment of cells.

In this research, a 3D hydrogel-based micro-scale-tissue-analog-chip (µTAC) is fabricated with an integrated optofluidic design for biomedical applications. These 3D hydrogels act as a scaffold for the cellular studies and as …

Vector Processor Virtualization: Distributed Memory Hierarchy And Simultaneous Multithreading, Seyedamin Rooholamin

Dissertations

Taking advantage of DLP (Data-Level Parallelism) is indispensable in most data streaming and multimedia applications. Several architectures have been proposed to improve both the performance and energy consumption for such applications. Superscalar and VLIW (Very Long Instruction Word) processors, along with SIMD (Single-Instruction Multiple-Data) and vector processor (VP) accelerators, are among the available options for designers to accomplish their desired requirements. On the other hand, these choices turn out to be large resource and energy consumers, while also not being always used efficiently due to data dependencies among instructions and limited portion of vectorizable code in single applications that deploy …

Cloud-Aided Wireless Systems: Communications And Radar Applications, Shahrouz Khalili

Dissertations

This dissertation focuses on cloud-assisted radio technologies for communication, including mobile cloud computing and Cloud Radio Access Network (C-RAN), and for radar systems.

This dissertation first concentrates on cloud-aided communications. Mobile cloud computing, which allows mobile users to run computationally heavy applications on battery limited devices, such as cell phones, is considered initially. Mobile cloud computing enables the offloading of computation-intensive applications from a mobile device to a cloud processor via a wireless interface. The interplay between offloading decisions at the application layer and physical-layer parameters, which determine the energy and latency associated with the mobile-cloud communication, motivates the inter-layer …

Instruction Fusion And Vector Processor Virtualization For Higher Throughput Simultaneous Multithreaded Processors, Yaojie Lu

Dissertations

The utilization wall, caused by the breakdown of threshold voltage scaling, hinders performance gains for new generation microprocessors. To alleviate its impact, an instruction fusion technique is first proposed for multiscalar and many-core processors. With instruction fusion, similar copies of an instruction to be run on multiple pipelines or cores are merged into a single copy for simultaneous execution. Instruction fusion applied to vector code enables the processor to idle early pipeline stages and instruction caches at various times during program implementation with minimum performance degradation, while reducing the program size and the required instruction memory bandwidth. Instruction fusion is …

On Greening Optical Access Networks, Mina Taheri Hosseinabadi

Dissertations

With the remarkable growth of fiber-based services, the number of FTTx subscribers has been dramatically increasing in recent years. Owing to the environmental concern, reducing energy consumption of optical access networks has become an important issue for network designers. In Ethernet passive optical network (EPON), the optical line terminal (OLT) located at the central office broadcasts the downstream traffic to all optical network units (ONUs), each of which checks all arrival downstream packets to obtain those destined to itself. Since traffic of ONUs changes dynamically, properly defining the sleep mode for idle ONUs can potentially save a significant amount of …

Subspace Methods For Portfolio Design, Onur Yilmaz

Dissertations

Financial signal processing (FSP) is one of the emerging areas in the field of signal processing. It is comprised of mathematical finance and signal processing. Signal processing engineers consider speech, image, video, and price of a stock as signals of interest for the given application. The information that they will infer from raw data is different for each application. Financial engineers develop new solutions for financial problems using their knowledge base in signal processing. The goal of financial engineers is to process the harvested financial signal to get meaningful information for the purpose.

Designing investment portfolios have always been at …

Oxidation Kinetics Of Metallic Powders, Hongqi Nie

Dissertations

Aluminum and magnesium are widely used in pyrotechnic formulations and other energetic materials; they are also common components of reactive alloys, e.g., Al-Mg and B-Mg, and others, which are potential fuels for explosives and propellants. Reaction mechanisms and oxidation kinetics of aluminum, magnesium and Al-Mg alloy powders in different oxidizing environments are investigated using thermo-analytical measurements. New methods of data processing are developed, relying on measured particle size distributions of the reactive spherical powders. It became possible to identify the reaction interface location for many heterogeneous metal oxidation processes; for several reactions, detailed kinetic descriptions are obtained.

For aluminum powders, …

Experimental And Modeling Studies In Membrane Distillation, Lin Li

Dissertations

A variety of microporous hydrophobic flat sheet membranes of polyvinylidene fluoride (PVDF) and expanded-polytetrafluoroethylene (e-PTFE) are studied to evaluate the influence of membrane properties on their performance in desalination by direct contact membrane distillation (DCMD) and vacuum membrane distillation (VMD) processes. The membrane thickness is varied between 23 μm to 125 μm; the pore size is varied from 0.05 μm to 0.45 μm. The porosity is generally high in the range of 0.7 - 0.8. DCMD experiments are performed over a hot brine temperature range of 65 °C to 85 °C and distillate temperature at 25 °C for various brine …

A Novel Approach To User Controlled Ambulation Of Lower Extremity Exoskeletons Using Admittance Control Paradigm, Kiran Kartika Karunakaran

Dissertations

The robotic lower extremity exoskeletons address the ambulatory problems confronting individuals with paraplegia. Paraplegia due to spinal cord injury (SCI) can cause motor deficit to the lower extremities leading to inability to walk. Though wheelchairs provide mobility to the user, they do not provide support to all activities of everyday living to individuals with paraplegia.

Current research is addressing the issue of ambulation through the use of wearable exoskeletons that are pre-programmed. There are currently four exoskeletons in the U.S. market: Ekso, Rewalk, REX and Indego. All of the currently available exoskeletons have 2 active Degrees of Freedom (DOF) except …

Custom Engineered Nanomaterials For Energetics And Energy Applications, Ani Abraham

Dissertations

Recent interest in reactive material has shifted to more custom formulations targeting specific applications. In this work, preparation and characterization of nanomaterials used for several energetics and energy applications are addressed.

The main challenge of this effort is to design and prepare nanomaterials which have significant improvements associated with combustion dynamics, reaction rates, sensitivity, biocidal effectiveness, moisture stability, and are environmentally safer over the existing energetics. Nanomaterials that are used to defeat stockpiles of chemical and biological weapons, modify ionosphere properties for transmission of optical and radio signals, and for energy storage are prepared under room or cryogenic temperatures via …

Antibacterial Efficacy Of Nanometals In Conjunction With Electrical Stimulus, Syed A. Hussain

Theses

Hospital related infections generally result from the combined effect of preexisting bacteria on the patient and invasive devices. This demonstrates the significance in improving these medical devices to increase the quality of life of the patients that require them. This study will attempt to evaluate the antibacterial efficacy of nanocopper particles and an electrical stimulus for the usage in medical device development and the hospital environment.

For devices such as catheters, infections typically result from bacteria entering the body from the outside. This is accomplished by bacteria attaching themselves to the exterior of the device and producing biofilm which allows …

Response Of Stretch-Injured Schwann Cells, Stephanie Iring

Theses

Axon fibers are covered by myelin sheath. After axonal damage, demyelination follows with the production of debris. In the Central Nervous System many studies have been performed to observe and analyze stretch injured axons, but very little has been done to study the white matter axonal tracts, oligodendrocytes. Schwann cells can help take a first look into stretch injured glia cells from the Peripheral nervous system. In order to observe changes in Schwann Cells a stretch injury device is used to produce the effects of severe and moderate injuries. Schwann Cells are stretch injured in both their undifferentiated and differentiated …

Dissolution Kinetics Of Model Api In Molten Polymer Excipients During Batch Processing, Shen Ji

Theses

In the pharmaceutical industrial application field, hot-melt extrusion (HME) has been recently introduced to develop new solid dosage forms and products. By dissolving the poorly–soluble active pharmaceutical ingredients (API) into water-soluble polymers, the bioavailability of the Class II (with low solubility and high permeability in water) API in Biopharmaceutical Classification System (BCS) could be significantly improved in the body. For readily water-soluble API, HME provides a new approach to produce a controlled release drug system. Hence, pharmaceutical HME is a promising processing method in the pharmaceutical industry.

However, HME has not been widely applied into the pharmaceutical industry. The thermal …

Magnetic Augmented Rotation System (Mars ) - Properties And Performance, Ruolei Liu

Theses

Magnetic Augmented Rotation System (MARS) is proposed as a system for conversion of mechanical energy into electrical energy. It works on the principle of magnetic coupling. Because it is contactless, compared with traditional gears, it increases the transfer efficiency from a driver to a rotor; reduces noise, requires no lubrication and has low maintenance cost. In order to assess the performance of MARS, a charging system based on MARS is implemented. This system includes rechargeable batteries in the range of 6 volts to 12 volts, a load in the form of a light bulb, a voltage transformer, and digital multimeter …

Effectiveness Of Water Quality Benefits Provided By Stormwater Management Facilities/Infiltration Basin, Vinicius Rodrigues De Mattos Barreto

Theses

Stormwater Best Management Practices (BMP) and devices are systems frequently built under assumed design performances, but rarely verified after construction. Their effectiveness in protecting the environment against pollutants carried by stormwater runoff has been extensively questioned and investigated. This research presents a case study of an infiltration basin in Medford, NJ to verify if the 80% expected Total Suspended Solids (TSS) removal as stated in the New Jersey Stormwater BMP Manual is actually achieved. A sampling pit was installed on the site and infiltrated water samples were collected during three rain events and TSS measurements were compared with the inflow. …

Effect Of Melt Method On Thoracolumbar Connective Tissue, Faria Sanjana

Theses

Approximately, 31 million adults in the United States suffer from low back pain (LBP). Altered connective tissue structure has been identified in adults with chronic LBP. Numerous novel treatments are being developed targeting the connective tissue and nervous system to relieve people from LBP. One such self-care treatment is the MELT method. The objective of this study was to determine whether thickness of thoracolumbar connective tissue and other biomechanical and viscoelastic properties of myofascial tissue in the low back region change in subjects with chronic LBP as a result of MELT.

Using ultrasound imaging and an algorithm developed in MATLAB, …

Effect Of Temperature On The Fracture Behavior Of Lead-Free Solder Joints, Patrick Thompson

Theses

The objective of the present study is to examine the effect of temperature on the fracture behavior of Cu-SAC305-Cu joints. To this end, double cantilever beam (DCB) specimens, consisting of a thin layer of Sn96.5Ag3.0Cu0.5 (SAC305) solder sandwiched between two copper bars, fabricated under standard surface mount (SMT) processing conditions are fractured under various temperatures with a MTS machine equipped with an environment chamber. The load-displacement behavior corresponding to crack initiation and the subsequent toughening before ultimate failure and the displacements near crack tip are recorded and used to calculate the fracture energy release rates. The fracture surfaces and the …

Koh Etching Of Silicon, Ying Wang

Theses

In this research, a series of comparative etching experiments on silicon wafers have been carried out using potassium hydroxide (KOH) for different experimental etching conditions for concentration, temperature and time on (100) orientation p-type silicon wafers. Besides the basic etching conditions, the position of the immersed wafer also has unpredictable effect on the etching process. This may be attributed to the relative contact position between the surface of the immersed wafer and the flow patterns of the stirred etching solution.

The surface morphology analysis indicates that the specific position of the wafer, with respect to the flow of the etchant, …

Preparation, Ignition And Combustion Of Reactive Metal-Sulfur Nanocomposites, Ziyue Zhong

Theses

Mechanical milling is applied to synthesize reactive metal-sulfur nanocomposites. Specifically, magnesium-sulfur, aluminum-sulfur and zirconium-sulfur nanocomposite powders are prepared. Each powder particle contained homogeneously mixed sulfur and respective metal. These materials are expected to be stable in room air. They are also expected to release sulfur upon ignition; the released sulfur may serve as a biocidal agent. The ignition temperatures of the three prepared sulfur-bearing materials fall in a range of 750 - 1000 K. All prepared materials are successfully ignited in electrostatic discharge experiment as well as in a constant volume explosion experiment. The most sensitive material to spark ignition …

Continuum Mechanical Analysis Of Space And Time Dependent Deformation Pattern Of Brain With Blunt Injury, Chen Miao

Theses

Deformation of human brain due to acceleration impact has been widely accepted as the direct connection to the Trauma Brain Injury (TBI). However, the limitation of obtaining deformation data of TBI is a major obstacle to understanding TBI mechanism. This experiment mainly focuses on developing a method to measure deformation pattern of brain with blunt injury. First of all, displacement data of markers on sagittal plane of an injury head model was collected using 3D reconstruction software after an impact test. Second, the displacement data was used to calculate 2D Lagrangian strain tensor and the principal strain. The temporal and …

Optimum Distance Between Ground Base Stations For High-Speed Train Communications Using Free-Space Optical Laser Links, Sina Fathi Kazerooni

Theses

High-Speed trains (HSTs) can travel at speeds up to 430 Km/h. The increasing adoption rate of HSTs, and large number of Internet-connected digital devices, pose a great demand for a fast and reliable Internet connection in high-speed trains. Different radio-frequency (RF) wireless communication systems have been studied for HSTs. However, RF wireless communications in high-speed mobility environments suffer from frequent handovers, penetration loss, and Doppler effect. These problems promote the use of other technologies such as free-space optical (FSO) communications to provide reliable Internet connection for HST’s passengers.

Two different approaches for performing signal handover using FSO technology for ground …

An Electromechanical System For Characterization Of Piezoelectric Materials, Ahmet Sait Asan

Theses

Piezoelectric materials have been used in medical applications for a long time due to their unique characteristics, which is to respond to mechanical stimulation by producing an electrical current and vice versa. They perform a pivotal role in medical applications both for diagnostic and therapeutic purposes. In this regard, characterizing the piezoelectric properties of these materials is crucial for their usage. In this particular study, an electromechanical system for measurement of piezoelectric output signals is designed and tested. The project is motivated by the question: can the piezoelectric properties be characterized by applying different mechanical stimulation waveforms and frequencies. Two …

Infrared Imaging - Case Studies And Applications, Shuang Du

Theses

Recent advancements in the manufacture of solid state detectors have led to significant improvements in the use and applications of infrared (IR) imaging. Compared with traditional imaging in visible light, infrared imaging has abilities to convey significant additional information. Applications in medicine require wavelengths in the range of 0.8 to 25 microns while metrology and astronomy, traditionally, require wavelengths in the range of 25 microns to 1 mm.

In this study, infrared imaging has been used as a tool to characterize a variety of objects and systems. Some of these case studies have been considered under conditions of thermodynamic non-equilibrium. …

Diffusivity Of Drug Actives In Transdermal Drug Delivery (Tdd), Natali R. Gendelberg

Theses

Transdermal Drug Delivery (TDD) through skin patches has many advantages including the following: slow and continuous administration of the therapeutic over long periods of time, timely dosage, accessibility, kinetic maneuverability, elimination of the “First Pass Effect” and negative side effects on the digestive tract. All of the above justify investment into further development of TDD therapies, despite the skin permeability restrictions posed on size and charge by the skin. As skin permeability varies between all individuals based on age, ethnicity and lifestyle, the determination of the proper drug dosages to be contained in the skin patch is highly reliant on …