Engineering Commons^™

Electrochemical Self-Assembly Of Porous Alumina Templates, V. Sadasivan, C. P. Richter, L. Menon, P. F. Williams

P. F. (Paul Frazer) Williams Publications

Porous alumina templates are fabricated by anodization of Al in an acid. The characteristics of the template, such as the pore diameter, interpore separation, and the periodicity of the porous structure depend on the conditions of anodization and the acid that is used as electrolyte. The variation of pore diameter and interpore separation as a function of anodization parameters are described. The use of porous alumina templates as masks to assemble nanoarrays is an important application and the deposition of Au nanodots on a surface of silicon is discussed.

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Neutronic Evaluation Of Zro2-Mgo Inert Fuels, E. Fridman, S. Kolesnikov, E. Shwageraus, A. Galperin

Fuels Campaign (TRP)

This report presents the results of the Task 3, defined in working program as: evaluation of burnable poison designs. Adopting the basic design of a standard PWR and Pu loadings required for 18-month cycle (results of Task 2), this part of the program is aimed to estimate performance of each BP design and BP material to address challenges of Fertile-Free Fuel (FFF) Concept. Finally, an optimal BP design will be developed and an overall feasibility of FFF concept will be determined. Basically, the main challenge encountered in neutronic design for a FFF core is to develop reactivity control system which …

Fabrication Of Hollow Waveguides With Sacrificial Aluminum Cores, John P. Barber, Donald B. Conkey, Jeffrey Ryan Lee, Neal B. Hubbard, Larry L. Howell, Aaron R. Hawkins, Gongliang Yin, Holger Schmidt

Faculty Publications

We have developed a process to fabricate dielectric waveguide structures with long hollow cores formed by etching a sacrificial core material. The process is compatible with other planar silicon fabrication techniques. Using aluminum as the sacrificial material, we have investigated fabrication limits and design parameters that determine mechanical integrity of the waveguides. Internal pressure due to the production of gaseous compounds during the core removal process was identified as the yield-limiting factor. A mechanical model based on finite element analysis and confirmed by experiment, predicts ultimate pressures sustainable by these structures. Waveguides less than 10 m wide with 2- m-thick …

Microwave Backscatter Modeling Of Erg Surfaces In The Sahara Desert, David G. Long, Haroon Stephen

Faculty Publications

The Sahara desert includes large expanses of sand dunes called ergs. These dunes are formed and constantly reshaped by prevailing winds. Previous study shows that Saharan ergs exhibit significant radar backscatter (σ˚) modulation with azimuth angle (∅). We use σ˚ measurements observed at various incidence angles and ∅ from the NASA Scatterometer (NSCAT), the SeaWinds scatterometer, the ERS scatterometer (ESCAT), and the Tropical Rainfall Measuring Mission's Precipitation Radar to model the σ˚ response from sand dunes. Observations reveal a characteristic relationship between the backscatter modulation and the dune type, i.e., the number and orientation of the dune slopes. Sand dunes …

The Value Of Mobile Applications: A Utility Company Study, Fiona Fui-Hoon Nah, Keng Siau, Hong Sheng

Research Collection School Of Computing and Information Systems

The value proposition of mobile applications i.e. the net value of the benefits and costs associated with the adoption and adaptation of mobile applications is discussed. A means-ends network that depicts the fundamental relationships among the objectives such as efficiency, effectiveness, customer satisfaction, security, cost, and employee acceptance, was developed. The network is useful to researchers as it highlights the issues, concerns, and values of mobile applications. The network help the managers and practitioners to achieve their companies' objectives of implementing mobile and wireless applications.

Working Postures Of Dentists And Dental Hygienists, Richard W. Marklin, Kevin Cherney

Mechanical Engineering Faculty Research and Publications

A joint study was conducted by a manufacturer of dental stools in the Midwest of the United

States and Marquette University to measure the occupational postures of dentists and dental hygienists. The postures of 10 dentists and 10 dental hygienists were assessed using work sampling and video techniques. Postura! data of the neck, shoulders and lower back were recorded from video and categorized into 30-degree intervals: O (neutral posture of respective joint), 30, 60 and 90 degrees. Each subject's postures were observed while they were treating patients during a four-hour period, during which 100 observations of postures were recorded at …

Observation And Characterization Of Radar Backscatter Over Greenland, David G. Long, Ivan S. Ashcraft

Faculty Publications

Characterization of the microwave signature of the Greenland snow surface enables delineation of the different snow facies and is a tool for tracking the effects of climate change. A new empirical observation model is introduced that uses a limited number of parameters to characterize the snow surface based on the dependence of radar backscatter on incidence angle, azimuth angle, spatial gradient, and temporal rate of change. The individual model parameters are discussed in depth with examples using data from the NASA Scatterometer (NSCAT) and from the C-band European Remote Sensing (ERS) satellite Advanced Microwave Instrument in scatterometer mode. The contribution …

Automatic Classification And Speaker Identification Of African Elephant (Loxodonta Africana) Vocalizations, Patrick J. Clemins, Michael T. Johnson, Kirsten Leong, Anne Savage

Electrical and Computer Engineering Faculty Research and Publications

A hidden Markov model (HMM) system is presented for automatically classifying African elephant vocalizations. The development of the system is motivated by successful models from human speech analysis and recognition. Classification features include frequency-shifted Mel-frequency cepstral coefficients (MFCCs) and log energy, spectrally motivated features which are commonly used in human speech processing. Experiments, including vocalization type classification and speaker identification, are performed on vocalizations collected from captive elephants in a naturalistic environment. The system classified vocalizations with accuracies of 94.3% and 82.5% for type classification and speaker identification classification experiments, respectively. Classification accuracy, statistical significance tests on the model parameters, …

Turbo Space-Time Coding For Mimo Systems : Designs And Analyses, Hangjun Chen

Dissertations

Multiple input multiple output (MIMO) systems can provide high diversity, high data rate or a mix of both, for wireless communications. This dissertation combines both modes and suggests analyses and techniques that advance the state of the art of MIMO systems. Specifically, this dissertation studies turbo space-time coding schemes for MIMO systems.

Before the designs of turbo space-time codes are presented, a fundamental tool to analyze and design turbo coding schemes, the extrinsic information transfer (EXIT) chart method, is extended from the binary/nonbinary code case to coded modulation case. This extension prepares the convergence analysis for turbo space-time code.

Turbo …

Experimental Technique For Studying High-Temperature Phase Equilibria In Reactive Molten Metal Based Systems, Alexandre Ermoline

Dissertations

The general objective of this work is to develop an experimental technique for studying the high-temperature phase compositions and phase equilibria in molten metal-based binary and ternary systems, such as Zr-O-N, B-N-O, Al-O, and others. A specific material system of Zr-O-N was selected for studying and testing this technique.

The information about the high-temperature phase equilibria in reactive metal-based systems is scarce and their studying is difficult because of chemical reactions occurring between samples and essentially any container materials, and causing contamination of the system.

Containerless microgravity experiments for studying equilibria in molten metal-gas systems were designed to be conducted …

Congestion Control In Resilient Packet Ring Networks, Alharbi Fahd

Dissertations

The Resilient Packet Ring (RPR) is a new metro technology; RPR shares SONET's ability in providing fast recovery from link and node failures as well as inherits the cost and simplicity of Ethernet. RPR, like SONET/SDH, is a ring based architecture consisting of two optical rotating rings (uni-directional). In RPR, packets are removed from the ring at the destination so that different segments of the ring can be used at the same time for different flows; as a result, the spatial reuse feature is achieved. Enabling the spatial reuse feature introduces the challenge of guaranteeing fairness among the nodes sharing …

Behavior Of Structural Concrete Members Strengthened By Composite Fabrics, Jian Chen

Dissertations

The new technique of using Fiber Reinforced Polymer (FRP) materials to repair and strengthen various concrete members is becoming more and more popular in structural retrofitting field. Among all the confining materials, Carbon Fiber Reinforced Polymer (CFRP) fabric jackets are identified as an effective way to enhance the strength and ductility of concrete members due to its superior mechanical properties. This study investigates the detailed structural behavior of confined concrete members using CFRP fabric jackets by both analytical and experimental approaches.

A series of CFRP wrapped concrete cylinder tests were conducted to study the compressive stress-strain behavior for CFRP confined …

Detection Of Network Anomalies And Novel Attacks In The Internet Via Statistical Network Traffic Separation And Normality Prediction, Jun Jiang

Dissertations

With the advent and the explosive growth of the global Internet and the electronic commerce environment, adaptive/automatic network and service anomaly detection is fast gaining critical research and practical importance. If the next generation of network technology is to operate beyond the levels of current networks, it will require a set of well-designed tools for its management that will provide the capability of dynamically and reliably identifying network anomalies. Early detection of network anomalies and performance degradations is a key to rapid fault recovery and robust networking, and has been receiving increasing attention lately.

In this dissertation we present a …

The Feasibility Of Micromachined Dynamic Resonant Beam Coriolis True Mass Flow Meter, Sang Hwui Lee

Dissertations

The technological advances of micro-electro-mechanical systems (MEMS) in the past two decades have been remarkable for innovations in microfluidic systems as well as automotive applications such as pressure sensors and accelerometers. MEMS flow sensing has emerged as a field of interest in microfluidics, with a variety of sensing methods being miniaturized, such as thermal anemometry, ultrasonic sensing and flow measurement based on the Coriolis effect. Coriolis sensing is particularly attractive since, unlike most other methods which provide volumetric flow information, Coriolis sensing is capable of providing a direct, true mass flow measurement. Because of this advantage, Coriolis flow sensing has …

Corrosion Studies On Alpha Tantalum And Beta Tantalum Coated Steel, Sung Min Maeng

Dissertations

Tantalum coating by sputtering, one form of physical vapor deposition (PVD), has been investigated as a replacement for chromium coatings on gun bores to protect them from erosion and corrosion due to its high ductility and high corrosion resistance in aggressive environments. When deposited as a film on steel substrates by sputtering, either α-Ta, β-Ta, or a mixture of both phases have been observed under varying deposition conditions. To evaluate corrosion behavior of Ta coatings, electrochemical impedance spectroscopy and potentiodynamic polarization were conducted as a function of coating thickness. The coating porosity was observed to decrease with increasing coating thickness …

Image Data Hiding, Zhicheng Ni

Dissertations

Image data hiding represents a class of processes used to embed data into cover images.

Robustness is one of the basic requirements for image data hiding. In the first part of this dissertation, 2D and 3D interleaving techniques associated with error-correction-code (ECC) are proposed to significantly improve the robustness of hidden data against burst errors.

In most cases, the cover image cannot be inverted back to the original image after the hidden data are retrieved. In this dissertation, one novel reversible (lossless) data hiding technique is then introduced. This technique is based on the histogram modification, which can embed a …

Bus Arrival Time Prediction Using Stochastic Time Series And Markov Chains, Rajat Rajbhandari

Dissertations

Public transit agencies rely on disseminating accurate and reliable information to transit users to achieve higher service quality and attract more users. With the development of new technologies, the concept of providing users with reliable information about bus arrival times at bus stops has become increasingly attractive. Due to the fact that bus operation parameters and variables are highly stochastic, modeling prediction of bus travel and arrival times has become one of the many challenging tasks.

Stochastic time series and delay propagation models to predict bus arrival times using historical information were developed. Markov models were developed to predict propagation …

Uniaxial And Triaxial Behavior Of High Strength Concrete With And Without Steel Fibers, Xiaobin Lu

Dissertations

This study first presents an extensive experimental research program on the true uniaxial and triaxial compression behavior for both high strength concrete (HSC) and steel fiber reinforced high strength concrete (SFHSC). The experimental study mainly focuses on the octahedral shear stress strain relationship of those two types of concrete, which is adopted as the basis to develop a new incremental constitutive model. Emphasis is also put on the investigation of the variation of tangent Poisson's ratio under not only uniaxial but also triaxial stress conditions. The effect of cyclic loading on this parameter is also addressed.

According to this research, …

Computational Studies Of Viscoelastic Multiphase Flows, Shriram B. Pillapakkam

Dissertations

A finite element code based on the level set method is developed for performing two and three dimensional direct numerical simulations (DNS) of viscoelastic two-phase flow problems. The Oldroyd-B constitutive equation is used to model the viscoelastic liquid. The code is used to study transient and steady state shapes of Newtonian and viscoelastic drops in simple shear and buoyancy driven flows. The roles of the governing dimensionless parameters: Capillary number (Ca), Deborah Number (De) and the polymer concentration parameter c, in determining deformation of drops and bubbles, are also analyzed.

The numerical code permits us to vary Ca, De and …

Development And Application Of Fractionation Procedure For Drinking Water Organic Matters, Yong Pu

Dissertations

USEPA mandates a control of disinfection by-products (DBPs) in finished drinking water and recommends reduction of natural organic matters (NOM), DBP precursors, to achieve this regulatory goal. Studies relating NOM with DBP include fractionation of water samples, characterization of collected organic fractions, fractions' formation potential tests, and jar or similar tests to remove NOM. This study discussed a current resin fractionation procedure on principle, procedure, and its efficiency when applied to water samples of low NOM (< 5mgIL). The primary objective of this research is to develop a fractionation procedure intended for water of low NOM by carefully applying mass balance concept through each fraction's fractionation and a selection of stable ion exchange resins. A new protocol was presented with triple columns of XAD-8 adsorption resin, one column of AG-MP-50 cationic resin, and another column of WA 10 weak anionic resin in sequence. This protocol was experimented and confirmed for its efficiency (±10% loss of mass) with samples from Canal Road (CR) and Raritan Millstone (RM) surface water treatment plants (WTPs) in central New Jersey. The second objective of this study is to develop a statistical model with a potential of online delineation of organic fractions of NOM. The resulting model based on samples of Passaic Valley Water Commission (PVWC) WTP in northern New Jersey was applied to predict organic fractions of samples from CR and RM plants. Paired T-test (paired t ratio 1.15 < t critical 2.02) indicated a good correlation between the predicted and actual fraction concentration. Finally, samples of Middlesex Water Company (MWC) were fractionated and Trihalomethane formation potential tests (THMFP) on collected fraction showed hydrophilic matters possessed a higher potential to produce TTHM in finished water than hydrophobic matter. Jar tests indicated while coagulation was effective in removing hydrophobic matter, it may not be optimum for removal of hydrophilic matter.

This study developed an accurate fractionation procedure for low NOM waters. It provided a better understanding of organic matter transformation at different treatment …

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …

Crystalization Studies In Hollow Fiber Devices, Dimitrios Zarkadas

Dissertations

Crystallization was examined under a new perspective and in a flow environment much different from that available in currently used industrial devices. Three crystallization techniques were tested in the unique flow environment offered by hollow fiber devices. In addition, a new type of heat exchanger based on hollow fibers was tested as well as the potential use of porous hollow fiber devices as mixing devices. Hollow fiber devices are compact, extremely efficient on a volumetric basis, easy to scale up and control and their inherent characteristics promote the creation of homogeneous temperature and concentration conditions on a scale considerably smaller …

Investigation Of Static And Dynamic Enhancement Of Laminar Natural Convection Cooling Of Electronics, Laurie Ann Florio

Dissertations

With the proliferation of consumer electronics devices and the increasingly demanding thermal control requirements for such devices, more effective and efficient means of cooling electronics are needed. The feasibility of three alternative approaches to enhancing pure natural convection cooling of electronics is investigated in the current research. The three static or dynamic methods investigated are alternate cross-flow passages, the strategic placement of transversely oscillating plates near the heat sources and a combined method using both the cross-flow passages and the strategically placed oscillating plates. These cooling methods are intended to operate in the regime for which natural convection cooling is …

In Vitro Drug Delivery Based On A Porous Membrane-Based Aqueous-Organic Partitioning System And Its Enhancements Through Mouse Skin, Qiuxi Fan

Dissertations

Novel approaches for transdermal drug delivery (TDD) based on a porous membrane-based aqueous-organic partitioning system have been investigated and successful deliveries were observed. Doxycycline hydrochloride (HCl), a polar antibiotic drug with a relatively large molecule weight (MW: 480.1) was studied as a basic model agent. Its controlled release using this technique was studied first. Satisfactory release profiles demonstrate the practical potential of such a system to achieve useful controlled release rates. The enhancer linoleic acid was essential to successful release using a mouse skin beneath a porous polymeric membrane. The transport rates of smaller molecules e.g., caffeine and nicotine from …

Executive Summary: Evaluation Of The Impact Of Vacant Home Space Conditioning Strategies On Summer Relative Humidity, Energy, And Peak Load, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

The Vacant Home Space Conditioning Study was sponsored by Florida Power & Light (FPL) as part of its Conservation R&D Program and carried out by the Florida Solar Energy Center (FSEC). In the US, about one in four retiree "snowbirds" make Florida their destination to escape the northern cold. Snowbird residents number more than 900,000 in Florida during the winter. In some counties of FPL's territory these seasonal residents compose up to 15% of the population (Shih, 1981). This pattern of seasonal occupancy creates a need for space conditioning guidelines for vacant homes to avoid mold problems while minimizing both …

Qos Constrained Cellular Ad Hoc Augmented Networks, Chi-Tung Chen

Dissertations

In this dissertation, based on different design criteria, three novel quality of service (QoS) constrained cellular ad hoc augmented network (CAHAN) architectures are proposed for next generation wireless networks. The CAHAN architectures have a hybrid architecture, in which each MT of CDMA cellular networks has ad hoc communication capability. The CAHAN architectures are an evolutionary approach to conventional cellular networks. The proposed architectures have good system scalability and high system reliability.

The first proposed architecture is the QoS constrained minimum-power cellular ad hoc augmented network architecture (QCMP CAHAN). The QCMP CAHAN can find the optimal minimum-power routes under the QoS …

Photocontrol Data Acquisition System For Lamp Life Prediction In High Pressure Sodium Lighting, Jeffrey William Tisa

Theses and Dissertations

This thesis begins with a brief historical account of high intensity discharge (HID) lighting. It begins in the seventeenth century and concludes with the modem high pressure sodium (HPS) lamp, which has become the most widespread HID lighting source due to its high efficacy (Lumens/Watt) and acceptable color rendition. Following a more in-depth discussion on the HPS lamp, a means of estimating the arc tube voltage of an HPS lamp from the confines of a photocontrol is introduced. This technique is implemented as part of a 'smart' photocontrol data acquisition unit that functions as part of a proposed practical asset …

Labview Controlled Study Of The Propagation Properties Of Ultrasound In Synthetic Fog Environment, Aparna Venkataraman

Theses

Diagnostic ultrasound employs pulsed, high frequency sound waves that are reflected back from body tissues and processed by ultrasound receivers to create characteristic images in varied applications such as cardiology, obstetrics and gynecology neurology and urology. Ultrasound intensity is primarily affected by the changes in acoustic impedance of the medium. Literature on ultrasound indicates that the propagation of ultrasound increases gradually as the density increases from air to water. Such studies have been confined to only the three states of matter and have never discussed a fog medium.

The primary objective of this thesis study was to design a system …

A Co-Processor Design To Support Mpi Primitives In Configurable Multiprocessor Designs, Rohan Bafna

Theses

The Message-Passing Interface (MIPI) is a widely used standard for inter-processor communication in parallel computers. This standard is normally implemented in software, thus resulting in large communication latencies. A hardware implementation can reduce communication latencies significantly, thereby increasing the bandwidth. However, this approach cannot be applied in practice to the very large set of functions in MPI.

Reconfigurable computing has reached levels where entire parallel systems can be built inside one or more FPGAs (Field-Programmable Gate Arrays). In this scheme, specialized components must be built for inter-processor communication and the resulting code is difficult to port to other reconfigurable platforms. …

Study Of Steganalysis Methods, Wen Chen

Theses

Steganography is the art and science of hiding the presence of conmunication by embedding secret message into digital images. The steganographic techniques can be applied in many areas. On one hand, people can benefit from their application. For example, they can be used for copyright protection. On the other hand, these techniques may be used by criminals or terrorists for malicious purposes. For example, terrorists may use the techniques to transmit the secret plan of terror attacks. Law enforcement and security authorities have concerns about such activities. It is necessary to devise the methods to detect steganographic systems. The detection …