Engineering Commons^™

Initial Hertzian Characteristics Of The Human Tooth As A Damage Tolerant Bio-Ceramic/Bio-Composite Bi-Layer, Ivory Camille Kilpatrick

Theses

The objective of this thesis was to investigate the Hertzian Contact response of human teeth and how the response behavior is related to that of model ceramic bi-layers (high modulus brittle ceramics on compliant substrates). Hertzian Contact is a blunt indentation method, which uses a hard spherical indenter to apply a normal compressive load. Clinical variables of masticatory (occlusal) force and cuspal curvature identify closely with the independent Hertzian variables of contact load and sphere radius [1]. This method offers insight into the role of microstructure and microstructure- sensitive mechanical properties. It was hypothesized that tooth damage modes and patterns …

Dynamic Friction Of Uhmwpe Angular Compliant Bearing For Joint Implants And Machinery, Max Roman

Theses

The feasibility of a unique design of orthopedic- joint implant is investigated. The work focuses on the dynamic friction characteristics of a new joint. This unique design can be also useful in machinery involving oscillating motion similar to that of the hip joint during walking. An elastomeric layer bonded behind the rigid acetubular cup can be beneficial in improving the durability of prosthetic implants. Angular compliance offered by the elastomeric layer reduces relative sliding between the surfaces, lowers contact stresses by distributing pressure more evenly, and reduces the possibility of incongruent loading conditions caused by misalignment. The application of a …

Characterization Of Alpha And Beta Phases Of Tantalum Coatings, Anto Yohannan

Theses

Sputtered tantalum forms two phases - α and β. The α and β phases have distinctly different crystalline structures and properties. The structure and the causes of formation of the β phase are still being studied by researchers. This is a study to distinguish and characterize these two phases. Samples from Bennet Labs and NJIT were characterized using techniques such as SEM, EDX, XRF, XRD, TEM and XAFS. Samples deposited at NJIT were used for an experimental study on the conditions favoring the formation of the phases, by depositing tantalum on heated steel and silicon substrates, additionally TEM analysis was …

Mechanical Design Of The Heater Used In Near Infrared Filter, Jun Ma

Theses

This thesis presents a design and analytical process in the application of the heater used in a near infrared filter working in Big Bear Solar Observatory, CA. The objective of the project is to achieve the physics parameters for the filter, which will be used in the observation of the solar activity.

The most important part of this design is to keep a relatively fixed temperature inside the oven-like heater. The reason is that optical properties of calcite (kind of filter in telescope) are pretty sensitive to a tiny disturbance on inside temperature. This was the biggest issue in this …

Encoding And Storage Components Of Verbal Working Memory As Revealed By A Factorial Design, An Fmri Study, Jason Steffener

Theses

In this fMRI study, the contributions of frontal and posterior brain regions to verbal working memory were investigated. A two-factor design with low and high memory load (2 and 5 letters) and short and long delay (4 and 12 secs.) as factors were used. Based on reports in the literature, we expect activity in the following frontal and parietal brain regions of interest (ROIs): Brodmann areas (BA) 6, 9, 46, 44, 45, 7 and 40. The analysis of collected flvM data involved image processing and statistical analysis methods including realignment, spatial normalization, spatial smoothing, temporal filtering, intensity normalization, statistical tests, …

Assessment Of The Recycled Concrete Aggregates Structural Suitability For Road Construction, Abdulla Yousef Ali Al-Ali

Theses

In most aspects of modem life, there is a consensus among practitioners and decision makers of the importance of preserving the environment, and to find alternatives to the scarce natural materials. This can be accomplished by better utilization of the natural materials and/or recycling or reclaiming their waste, specially, if they are of finite resources. The recycled material could be an attractive alternative (both environmentally and economically) if its characteristics are proven to be close to those of the natural material.

Utilizing recycled mineral aggregates in the construction field in general and in highway pavement in specific is somehow governed …

Evaluation Of Some Organic Inhibitors For Stainless Steel Corrosion Using Different Electrochemical And Surface Techniques, Maryam Hassan Saeed Al-Hassan

Theses

Stainless steels have been extensively used in automotive, industrial, electronics, etc., applications. Iron (Fe) and chromium (Cr) are the main elements with weight percentage contribution of 60-75% and 10-25% respectively. Other elements, such as Ni, Co, Mo, Mn, C etc. are also present with variable concentrations. The purpose of this work is to use different electrochemical and surface techniques to study the corrosion behavior of stainless steel type 316 (percent composition of different chemical elements are listed in table 1) in acid media in presence and absence of different thiophene derivatives (list of inhibitors in figure 1). Moreover, other important …

Impedance And Photo-Electrochemical Properties Of Oxide Films On Stainless Steel Formed By Different Polarization Techniques, Mona Salim Saleh Ai Kaabi

Theses

Stainless steel alloys have a very active and important role in industry. Because many of

These industries have to work in aggressive media; stainless steels are threatened by corrosion

Which may affect their performance and cost the manufacturers millions of dollars yearly.

Several treatments have been taken part to solve this problem; one is by forming a protective

Oxide layer on the stainless steel (SS) surface to prevent it from corrosion. In this thesis; this way of protecting SS Surface is applied to two different types of Stainless Steel, those are AISI 316 and AISI 31 0; respectively. The oxide …

Characterization Of The Dependant Pile Capacity In Glacial Deposits By Dynamic Load Tests, Upendra L. Karna

Theses

A study of the effects of time on axial pile capacity in glacial deposits is presented in this report. The dynamic and static load database test results of the Route 21, Viaduct Replacement project are studied and analyzed. In this project two sizes (18-inch and 24-inch dia.) of closed end pipe piles varying in length 100 to 150 feet driven through highly variable glacial deposits were utilized. Within a small reach the subsurface conditions and the behavior of pile capacity with time varied considerably. About 112 piles were tested dynamically by Pile Driving Analyzer. Restriking was performed on fifty-nine piles …

A Cad-Mlca Interface For Next-Generation Dfe Tools, Jun He

Theses

Environmental concerns and rising product disposal costs have pressed manufactures to make more environmentally friendly products and customers to use and dispose of them in an environmental responsive way. Thus the practice of Design for Environment (DFE) is becoming essential in today's industrial environment. Life Cycle Assessment (LCA) provides different ways for the environmental assessment of products. One critical step in performing lifecycle assessment of any product design is to collect design-related data. The common way based on manual input for traditional DFE tools is not only cumbersome and time-consuming but also error-prone.

This thesis presents the characteristics of a …

Silicon Based Ir Filters, Prakash Mokashi

Theses

The design and fabrication of silicon based IR (Infrared) filters for high-speed optical communication systems are the topic of this thesis. Its novelty is in two aspects: 1) Use of silicon wafers as an optical guiding medium; 2) Use of wafer bonding technique to attach two optical elements together.

The structure consists of two optical waveguides, the bus waveguide and the drop channel waveguide. A ring on top of these waveguides couples them in such a way that only one narrow spectral line is removed from the bus waveguides which propagates in the dropchannel waveguide. The assembly is fabricated using …

Optical Properties Of Photonic Crystals, Anand G. Shenoy

Theses

The ability to confine light in three dimensions has important implications for quantum optics and quantum-optical devices. Photonic crystals, the optical analog of electronic crystals, provide us a means of achieving this goal. This analogy has motivated a whole new series of experimental and theoretical searches for elusive photonic band-gap structures. Combinations of metallic and dielectric materials can be used to obtain the required three-dimensional (3D) periodic variation in the dielectric constant. This could pave the way for photonic crystal structures that have widespread applications.

The working of 3D photonic crystals into the wavelength regimes where most optoelectronic devices operate, …

Propagation And Scattering Of Collimated Beam Wave In Vegetation Using Scalar Transport Theory, Michael Yu-Chi Wu

Theses

The scalar time-dependent equation of radiative transfer is used to develop a theory of pulse beamwave propagation and scattering in a medium character ized by many random discrete scatterers which scatter energy strongly in the forward scattering direction. Applications include the scattering of highly collimated millimeter waves in vegetation and optical beams in the atmosphere. The specific problem analyzed is that of a periodic sequence of Gaussian shaped pulses normally incident from free space onto the planar boundary surface of a random medium half-space, such as a forest, that possesses a power scatter (phase) function consisting of a strong, narrow …

Simulation Modeling For Integrated E-Supply Chain Management, Pornsarun Wirojanagud

Theses

E-supply chain management is an emerging area of interest as companies begin to explore the Internet's potential to restructure supply chain relationships. The environmental impact of e-supply chain management is a critical issue towards sustainability. This thesis discusses and models an integrated e-supply chain network accounting for material and information flows throughout the supply chain in order to analyze the environmental implications and tradeoffis with other system characteristics. The network structure has complex interactions between various entities. In order to understand and analyze dynamic performance, a discrete-event simulation approach is utilized. An integrated tool was developed using the Arena simulation …

Structures, Intramolecular Rotation Barriers, And Thermodynamic Properties Of Methane And Ethylene Carbons Bonding To Two Unsaturated Groups : Ethylene, Acetylene, Phenyl And Carbonyl, Manish H. Gurbani

Theses

Enthalpy, ΔH_f°₂₉₈, entropy, S°₂₉₈ and heat capacities C_p(T) (300 ≤ T/K ≤ 1500) are determined for Methane, bi-phenyl (CCB2H2); Methane, phenyl-vinyl (CCBCDH2);Toluene, 1-formyl (CCBCOH2), Propyne, 3-phenyl (CCBCTH2); 1,4-pentadiene (CCD2H2); Propene, 3-formyl (CCDCOH2); Methane, di-formyl (CCO2H2); Propyne, 3-formyl (CCOCTH2); Methane, di-ethynl (CCT2H2); Ethene, bi-phenyl (CDCB2); 1,4 Butadiene, 3-phenyl (CDCBCD); Ethene, I-ethynl-l-phenyl (CDCBCT); 1,4 Butadiene,3-vinyl (CDCD2); 1,4 Butadiene, 2-ethynl (CDCDCT) and Ethene, 1,1di-ethynl(CDCT2) using density functional B3LYP/6-31G(d) calculation method. Molecular structures and vibration frequencies are determined at the B3LYP/6-31G(d) density functional calculation level. Evaluation of data from the isodesmic reactions results in ΔH_f° …

A Novel Approach Towards Usability Studies For Visual Search Tasks In Graphical User Interface Applications Using The Activity Theory Approach, Tirthankar Sengupta

Theses

The field of Human Computer Interaction still strives for a generalized model of visual search tasks (icon search, menu search, text search, label search, search through hypertext and feature recognition). The existing models of visual search, in spite of being impressive, are limited under certain perspectives due to lack of generality. The thesis tries to provide a holistic approach for the modeling of visual search tasks in graphical user interfaces from the Activity Theory (AT) perspective with the aim of rendering a theoretical bridge between HCI and Psychology. A detailed review of literature from the variegated discipline contributing to the …

Partial Characterization Of Extruded Collagen Tubes With Varied Material Deposition And Orientation Based On Rotation Rate And Linear Draw Speed, Richard Peter Hoppe

Theses

This study established protocols for extrusion of collagen tubes from an extruder made by the ZOKO Corporation of Czechoslovakia. Using a viscous collagen base material, collagen tubes can be formed with changes in rotation rates from 0 rpm to 260 rpm and linear draw speeds from 383 mm/min to 1270 mm/min with a constant extrusion rate of 50 cm²/min. These tubes, with further research and treatment, can be used for various medical applications including vascular implants and nerve conduits.

Post-extrusion, chemical crosslinking of the collagen increased the cohesiveness and mechanical integrity of the tubes. Microscopic photographs confirmed higher …

A Laboratory And Field Study Of The Attenuation Of Sound Intensity Using A Whistle As The Sonic Generator, Navneet Kumar

Theses

This study investigated the attenuation of sound intensity using a whistle as the sonic generator along with the detailed analysis of all the previous studies. Attenuation of sound in air studies were performed in Otto H. York Center for Environmental Engineering and Science at New Jersey Institute of Technology. Sound attenuation through air was measured by doubling the distance for each of five whistles. It was concluded that Whistle No.5 gives the highest sound intensity of 140.54 dB at a distance of 0.75 ft , the closest distance used for measurement, at a air flow rate of 7.5 SCFM. These …

An Efficient Expression Of The Timestamp And Period In Packet-And Cell-Based Schedulers, Dong Wei

Theses

Scheduling algorithms are implemented in hardware in high-speed switches to provide Quality-of-Service guarantees in both cell-based and packet-based networks. Being able to guarantee end-to-delay and fairness, timestamp-based fair queuing algorithms, which include SCFQ, WFQ, WF2Q and WF2Q+, have received much attention in the past few years. In timestamp-based fair queuing algorithms, the size of timestamp and period determines the supportable rates in terms of the range and accuracy. Furthermore, it also determines the scheduler's memory in terms of offchip bandwidth and storage space. An efficient expression can reduce the size of the timestamp and period without compromising the accuracy. In …

Development And Application Of A Computer Simulation Tool For Ecological Risk Assessments, Haiyi Lu

Theses

In an effort to improve tools in ecological risk assessment (ERA), an ERA software tool was developed and applied. Based on a preliminary evaluation of existing ecorisk models, the relative deficiencies were identified and included the need for a user-friendly interface, an interactive database management system (DBMS), and a comprehensive evaluation of exposure pathways. In this research, Visual Basic (VB) 6.0 and Microsoft SQL server were selected for developing the Windows-based interface and local DBMS, respectively. For the exposure estimate, Yuma and Aberdeen Proving Grounds were identified as baseline ecosystems. Terrestrial and aquatic plant and animal receptor selection was based …

Optimization Of Nitrogen Removal In Sequencing Batch Reactor, Suppakit Poonyachat

Theses

Operating parameters for sequencing batch reactor have the influenceon each substrate concentration. Concentration profile changes as operationparameters are changed. The study was conducted to model the variationin effluent concentration from sequencing batch reactor. MLVSS and cycletime are the parameters that were varied. Concentration in Fill, React,and Settle Period were calculated by using kinetic equations.

The results can show that these parameters have effects on the concentrationprofile. The increase of MLVSS can lower the concentration of BOD andammonium concentration in React period. Increasing MLVSS can show thatmore substrate utilization and nitrification process occur more rapidly.Concentration of nitrate at the end of …

Deposition Of Tantalum On Steel By Sputtering, Bhavin Shah

Theses

Recent interest in tantalum deposition comes from two different applications. One is in microelectronics where thin tantalum films (< 1 µm) are used as diffusion barrier layers for copper interconnects. The other involves its application as a material for corrosion and wear resistant coating on surfaces that are subjected to high stresses and harsh chemical and erosive environments.

This thesis is a part of the investigation done at the Ion Beam and Thin Film Research Laboratory at NJIT to study the deposition conditions and properties of tantalum thin films. It includes the design and construction of Planar D.C. Magnetron Sputtering System and Cylindrical D.C. Magnetron Sputtering System for deposition on the planar and cylindrical surfaces of steel, respectively. The electrical characteristics of the cylindrical system were tested in a range of pressures and conditions for initiation and maintaining of …

Highway Advisory Radio In The State Of New Jersey, Thomas Mark Nemeth

Theses

Highway Advisory Radio (HAR) is a broadcasting system used by transportation agencies to disseminate vital real-time traffic information to motorists. Each transmitter is restricted by the rules and regulations of the Federal Communications Commission (FCC) to an average broadcast radius of three to five miles. Most commonly these transmitters are located at major highway intersections, such that motorists may take alternate routes in case of congestion or emergencies.

All operational HAR transmitters in New Jersey were identified and their coverage zones were quantitatively characterized in terms of the signal to noise ratio at the receiver. These experimental results were then …

A Study And Some Experimental Work Of Digital Image And Video Watermarking, Tsui-Feng Liu

Theses

The rapid growth of digitized media and the emergence of digital networks have created a pressing need for copyright protection and anonymous communications schemes. Digital watermarking (or data hiding in a more general term) is a kind of steganography technique by adding information into a digital data stream. Several most important watermarking schemes applied to multilevel and binary still images and digital videos were studied. They include schemes based on DCT (Discrete Cosine Transform), DWT (Discrete Wavelet Transform), and fractal transforms. The question whether these invisible watermarking techniques can resolve the issue of rightful ownership of intellectual properties was discussed. …

Emulation Of The Dataflow Computing Paradigm Using Field Programmable Gate Arrays (Fpgas), Segreen Ingersoll

Theses

Building a perfect dataflow computer has been an endeavor of many computer engineers. Ideally, it is a perfect parallel machine with zero overheads, but implementing one has been anything but perfect. While the sequential nature of control flow machines makes them relatively easy to implement, dataflow machines have to address a number of issues that are easily solved in the realm of control flow paradigm. Past implementations of dataflow computers have addressed these issues, such as conditional and reentrant program structures, along with the flow of data, at the processor level, i.e. each processor in the design would handle these …

Testing Of Semiconductor-Based Adsorption Modified Photosensitive (Samp) Sensor For Response To Toluene, Ashish Agrawal

Theses

The response of semiconductor-based adsorption modified photosensitive sensor is based on the dye-enhanced photoconductivity of a CdS semiconducting film. The change in this photoconductivity is brought about when organic molecules are sorbed onto the dye-coated surface. The response is related to the overlap in the infrared spectrum of the dye with that of the analyte.

This research was carried out to study the response of the sensor to a typical hydrocarbon, toluene. The sensor was tested for its response to concentrations of toluene ranging from 2.6 ppm to 200 PPM in nitrogen. The sensor was tested under non-flow conditions and …

An Automated Approach For Comparative Analysis Of Interval And Heart Rate Variability, Taral Oza

Theses

Cardiovascular disease is the primary cause of death in the adult population. Half of these cardiac deaths occur as sudden death. Some of the parameters from the surface ECG recording (a noninvasive technique) carry important information and have special significance in research, as they are good indicators of diseases leading to heart attacks, sudden cardiac death and other similar cardiac problems. Measurement of QT interval variability and heart rate variability are two such parameters, which has received much attention of researchers.

An algorithm has been developed to measure and compare the two significant parameters, the QT interval variability and the …

Reactive Media For Chromium Reduction Under Alkaline Conditions For Use In Permeable Reactive Barriers, Sachin V. Apte

Theses

The purpose of this study was to select the appropriate reactive media for chromate reduction to treat groundwater (high pH) with permeable reactive barriers. The study addresses groundwater contamination for three chromium refining sites located in Hudson County, New Jersey. The use of iron (Fe⁰) as a reactive medium was studied and found to be insufficient for use in permeable reactive barriers because of the high pH conditions of groundwater at these sites. Pyrite and iron (Fe⁰)-pyrite mixtures were studied as viable reactive media by considering their passivation kinetics, reductive capacities and solubility properties.

Column experiments …

Design And Implementation Of An Intranet-Solution Especially With Workflow Aspects, Robert Loew

Theses

An Intranet support a new or simply an easier information system for all the workers within a company using internet technology. On the one hand, employees can use Web technology and very simple tools to provide and navigate information. On the other hand, the costly and time-consuming business of installing and maintaining software on local PCs can be avoided by using Browser-based Intranet applications. Ideally, it would be possible to access all forms of information processing using one and the same Web browser. This is the aim of the Intranet Project upon which this thesis is based.

Various technologies for …

Uniform Random Number Generation Using Pseudorandom Binary Sequences, Susan Rea

Theses

Random numbers have conventionally been used in a range of applications such as numerical analysis, lotteries and computer simulation and as cryptographic keys. The algorithms used for the production of random numbers are termed pseudorandom, as the numbers produced are not truly random as they emanate from a deterministic periodic source that is they are predictable if a subset of the sequence is known. However, for most applications these pseudorandom number sources are entirely suitable.

For cryptographic key sources, however, the random number sequences must be statistically good and difficult to predict. Linear feedback shift registers are presented in this …