Engineering Commons^™

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 …

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 …

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 …

Analysis And Synthesis Of Primary Side Cycle By Cycle Control Of Isolated Flyback Converters, Radoslaw Nalepa

Theses

This work presents the analysis and design of an isolated flyback converter, without feedback from the load side. The converter is controlled from the primary side using the switch voltage and innovative control circuit topologies.

A detail study of the flyback circuit is undertaken including all known parasitics. Besides the standard parasitics, for example the capacitor resistive effect, other more subtle effects are included in the model development such as inter coil couplingj source capacitance etc. Development of these models has provided information about circuit simplifications without losing accuracy of the model. As a consequence of this model development, it …

To Research, Analyse And Install An Optimised Maintenance Management System For A Medium Sized Manufacturing Company: A Textile Company Case Study, Christopher O'Donoghue

Theses

Modern manufacturing is continually striving to ensure that products are made to higher levels of quality with faster lead times and at the lowest possible costs. Manufacturing production has never been more reliant on machines and automated processes than it is today. This thesis investigates the management philosophies that are in existence, which cater specifically for maintenance and maintenance related issues. Management philosophies such as Reliability Centred Maintenance (RCM), Total Productive Maintenance (TPM), Profit Centred Maintenance (PCM), asset management (AM), Predictive Maintenance (PdM), Condition Based Maintenance (CBM) and World Class Maintenance (WCM) have increased company profits by drastically reducing maintenance …

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 …

Dynamics Of Pancake Vortices In A Finite Stack Of Superconducting Copper Oxide Layers, Mariam Mustafa Ahmad Al Marzoqi

Theses

The high temperature superconductors are very promising materials in a wide range of applications, starting from the electricity power supply. They play a lifesaving function through imaging systems. Even major internet and communication advances depend on these materials.

Superconductivity in these materials occurs particularly in the copper-oxide planes. However, since these materials are type-II superconductors, magnetic fields can penetrate these materials in quantized amounts of flux called vortices without destroying completely superconductivity, but producing some resistance, due to vortex motion. In order to overcome the resistance problem, vortices must be pinned to prevent their motion and hence eliminate the resistance. …

Dynamic Performance Of Isolated Power Converters, David Badia

Theses

Isolated power converters are primarily used in applications where electrical galvanic isolation is required for safety purposes. They are also used in applications, which require various output voltages level. They have been studied from many different aspects, but in this thesis the fundamental circuits of the flyback, the forward and the half-bridge converters are studied and compared extensively, with regard to their dynamic performance.

This analysis will lead us to a better understanding of their behaviour, that is a crucial point in the selection of each topology for a particular application. Moreover, the dynamic response of each converter is different; …

Nanofiltration-Based Diafiltration Process For Solvent Exchange In Pharmaceutical Manufacturing, Jignesh P. Sheth

Theses

Commercially available solvent stable polymeric nanofiltration membranes were used to study the nanofiltration and diafiltration operations in the context of the pharmaceutical industry. Experimental results are presented for a two-step operation involving the preconcentration of a feed solution via nanofiltration followed by the replacement of the first stage solvent with a second solvent via diafiltration in two stages. Membranes MPF-50 and MPF-60, having molecular weight cut-offs of 700 and 400 respectively, were used in the present study. A solution of erythromycin (MW 734) in ethyl acetate was preconcentrated via nanofiltration followed by replacement of ethyl acetate with methanol via batch …

Autonomic Activity In Gulf War Veterans Using Heart Rate And Systolic Blood Pressure Variability, Maryann S. Fam

Theses

Heart rate variability (HRV) describes variations of heart rate and is attributed to cyclic fluctuations in autonomic tone. The different methods of heart rate variability analysis allow for a non-invasive assessment of autonomic activity. This study analyzes the heart rate variability through both frequency domain methods and joint time-frequency domain methods which were executed through the LabVJEW graphical programming language. These algorithms were utilized to assess autonomic nervous system activity in Gulf War veterans with no health complaints versus Gulf War veterans with chronic fatigue syndrome. The heart rate variability analysis was obtained from acquired measurements of heart rate and …

Reduction Of Peak To Average Power Ratio In Ofdm And Ofdm-Cdma System, Jie Cheng

Theses

High Peak to Average Power Ratio is a main problem in Orthogonal Frequency Division Multiplexing(OFDM) system and Orthogonal Frequency Division Multiplexing -Code Division Multiple Access (OFDM-CDMA) system. Considering a compensated High Power Amplifier(HPA), in order to keep linearity for amplification, Input Back-Off(IBO) of the HP-A, has to be increased for handling a high PAPR. Higher 1130 will make HPA less efficient. Additionally, a signal with high PAPR will suffer clipping when PAPR is larger than 1130 of the HPA. Clipping can cause the distortion of the signal and deteriorate the performance of the system. Reduction of PAPR is a main …

Phase Tunability In A Conductor Backed Coplanar Waveguide Patch Antenna, Idan Mandelbaum

Theses

Traditionally beam steering in phase array antenna systems is achieved using tunable phase shifters or switched feed networks. Here, a tunable patch antenna element is suggested as a novel alternative to a combination of a radiating element and a phase shifter. A conductor backed coplanar waveguide patch antenna is chosen due to its suitability to mounted external tuning elements, using varactor diodes. Limited types of lumped tuning circuits, using varactor diodes, have been tested, though a lumped as well as distributed tuning is feasible in the chosen antenna configuration. Approximate analytical models for coplanar waveguide patch antennas with finite ground …

Drowsy Driver Data Acquisition System, Rafael Norat

Theses

This thesis focuses on detecting the drowsiness of a driver based on differentiation of the EEG signal activity between the eyes open and eyes closed states. Here, it is observed that there is a significant increase 'in a 10 Hz component of the alpha rhythm activity when the subject under test closes his / her eyes. This phenomenon was observed when electrodes were attached to the occipital region. A more desirable approach is to develop a non-intrusive measurement based on a multiturn differential coil combination utilizing a low noise high gain amplifier. The system developed here used an 80,000 turn …

Nanoporous Sio2/Vycor Membranes For Air Separation, Mihir Tungare

Theses

Porous Vycor tubes with 40Å initial pore diameter were modified using low pressure chemical vapor deposition (LPCVD) of silicon dioxide N0₂). Diethylsilane (DES) in conjunction with nitrous oxide (N₂O) was used as a precursor to synthesize these SiO₂ films. The aim of this study was to obtain a considerable selectivity between species of comparable size and hence N₂O was used. The use of N₂O was believed to make the process self-limiting. DES was allowed to flow through the tube and N₂O on the outside in the chamber at 550°C …

Preparation And Properties Of Tantalum Silicide Films On Silicon Substrates, Lei Jin

Theses

Tantalum silicide (TaSi₂) thin films were sputter deposited on p- type and n- type silicon substrates using VARIAN 3125 magnetron DC sputtering system with TaSi₂ target. The thicknesses of TaSi₂ thin films considered in this study are 200Å, 600Å and 1000Å, respectively. The TaSi₂/Si wafers were annealed at temperatures in the range of 400 to 900°T. The sheet resistances of TaSi₂ thin films with various thicknesses were measured by four-point probe before and after annealing. The sheet resistance decreases with increase in annealing temperature and decreases with the increase in thickness of TaSi …

Feasibility Study Of Rotating Fluidized Bed As A Dry Coater And Granulater, Manish Sawhney

Theses

This study is directed at enhancing our understanding of the mechanism of dry coating and granulation in a rotating fluidized bed (RFB). The main objective was to study the feasibility of the coating and granulation processes using an REB, both quantitatively and qualitatively.

A force balance and kinetic model is applied to explain the coating phenomenon and also to investigate why coating takes place in certain particle material systems and not in others. An equation for the resultant velocity with which one particle collides with another has been suggested for the rotating fluidized bed coater. A condition, which predicts whether …

Numerical Studies Of Deep Bed Filtration, Chan-Gyun Shin

Theses

Deep bed filtration is a process used to separate small solid particles suspended in a fluid by using granular solids as the collecting medium. The filter efficiency depends on many parameters such as the Reynolds number, particle drag coefficient, the ratio of the diameter of injected, and filter particles, etc.

In the present work we model the porous media flow (solution of the Navier-Stokes equations) by using a computer code developed by Dr. P. Singh and we restrict our analysis to the case of two dimensional periodic porous media. The computational domain is discretized using the finite element method. In …

A Study Of The Parameters And Stipulations Involved In The Design Of Prosthetic Limb Socket Liners, Sally F. Shady

Theses

The objective of this thesis is to illustrate the parameters that define and characterize the elements necessary for an optimal prosthetic socket interface design. Previous studies have revealed that the industry is manufacturing materials that are causing irregularities in gait patterns and causing major discomfort for transtibial amputees. As a result, chances for recovery and rehabilitation of many patients have been greatly reduced.

This study has indicated that the success of a socket liner depends on quantitative and qualitative factors that assess the overall efficacy of an artificial limb. Quantitative analysis is observed through calculations and deviations in gait cycles, …

Biomechanical Evaluation Of Patient Transfers, Charles Costa

Theses

The purpose of this study is to identify the problem encountered when a patient with limited strength and mobility needs assistance in transferring from a wheelchair to another location.

This study took advantage of ergonomic techniques to isolate the source of stress, and limited these stresses according to the standards of the National Institute of Safety and Health Administration.

A device was developed whereby the stresses of a patient transfer were eliminated. By using a conventional wheelchair and a recliner as a starting point, effectively combining these components into a single multifunctional unit the goal of reducing stress was achieved. …

Design And Fabrication Of Optical Resonators, Pushkar Moholkar

Theses

The design and fabrication of ring optical resonators for high-speed optical communication systems is 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 drop-channel waveguide. The assembly is fabricated using wafer-bonding technique …

Current-Voltage Characteristics Of Tasi2/Si And Mos Devices Using Labview, Prasant Tangirala

Theses

Analyses of current-voltage (LV) characteristics of Schottky Barrier Diodes (Tantalum Suicide) and Metal Oxide Semiconductor (MOS) Devices, using LabVIEW^TM, has been presented here. LabVIEW^TMTM, a graphical program development application, has been used to program a computer-driven Keithley Source Measure Unit (SMU) for device characterization. The SMU, which can be used as a Source Voltage - Measure Current as well as Source Current - Measure Voltage instrument, is used in the Source Voltage -Measure Current mode in this study. A General Purpose Interface Bus (GPIB) IEEE 488.2 has been used to interface the SMU with LabVIEW^{TM …}

Gait Development For Use In Dynamic Gait Optimization Of Qudrupedrobot Walking, Mark Will

Theses

The ability of walking robots to operate in areas that are inaccessible to wheeled robots has lead to significant research in the field of gait development and optimization for these robots. In this particular study, a catalog of gaits for use in a dynamic gait optimization system to optimize the walking speed of the quadruped Arturo robot on flat terrain is developed. This catalog of robot gaits was developed using a genetic algorithm formulation; various combinations of the selection, mutation, and crossover operators were analyzed.

The Arturo robot was modified so that physical verification of the developed gaits could be …

Development Of A Demanufacturing System Modeling And Simulation Tool, Jingjing Hu

Theses

This thesis develops a demanufacturing system modeling and simulation tool as an interface between simulation methods and demanufacturers. This tool can mimic the behavior of demanufacturing facility and obtain penetrable understanding of the system. By this modeling tool, one can intuitively analyze the behavior of a system and improve the operational efficiency. Detailed designs on the simulation tool including user interface, logic, and user view are presented in this thesis. The initial prototype version of the system modeling and simulation tool has been completed with fourteen modules in the developed template. Each object in the template refers to a specific …

Programmable Latching Probe Microstructures For Wafer Testing Applications, Salima Taifa Sadeq

Theses

The objective of this thesis is to design a programmable wafer testing array on a single chip based on micro electromechanical systems (MEMS) and VLSI. The wafer-scale integration in this thesis is a programmable array of test probes that are used for engineering test of VLSI and ULSI silicon integrated circuits at the wafer level. This consists of two subsystems (1) the VLSI address circuits used for addressing and controlling the MEMS on the chip and (2) the latching probe MEMS microstructure array that actuates into position for testing VLSI wafers. Each of the subsystems have been designed, analyzed and …

An Algorithm For Fast Route Lookup And Update, Pinar Altin Yilmaz

Theses

Increase in routing table sizes, number of updates, traffic, speed of links and migration to IPv6 have made IP address lookup, based on longest prefix matching, a major bottleneck for high performance routers. Several schemes are evaluated and compared based on complexity analysis and simulation results. A trie based scheme, called Linked List Cascade Addressable Trie (LLCAT) is presented. The strength of LLCAT comes from the fact that it is easy to be implemented in hardware, and also routing table update operations are performed incrementally requiring very few memory operations guaranteed for worst case to satisfy requirements of dynamic routing …

Development And Integration Of A Decision Support System For Electronic Outsourcing Into Telemanufacturing Service Provider, Vikram Batra

Theses

The use of computers and Information Technology enables manufacturers, especially small and medium size enterprises (SMEs) to improve productivity and increase manufactuning flexibility. Telemanufactuning or manufacturing in virtual environment is one of the infrastructures that facilitate the use of information superhighways and computer technology to attain these goals. Broadly defined, Telemanufactuning is the utilization of services accessed via communication networks and across information superhighways to perform in real time, operations and processes essential to the design and production of items. It can be a key enabler for decentralized manufacturing using global resources and expert design teams. In addition to updating …

Bounded Beam Wave Pulse Propagation And Scattering In Random Media Based On The Radiative Transfer Theory Using 2-D Gauss Quadrature Formula, Sheng-Kai Hu

Theses

The scalar time-dependent equation of radiative transfer is used to develop a theory of bounded beam wave narrow band pulse propagation and scattering in a medium characterized by many random discrete scatters, which scatters 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 scatter (phase) function consisting of a …

A Method Of Tracking Eye Motion For Human-Computer Interface, Martin Maranski

Theses

It would be of value to create another device for interfacing with a computer besides the commonly used handheld devices; one option is to determine where the user is looking on the screen. The major obstacle to overcome in this task is to be able to reliably track the motion of the iris and pupil in the eye. A method to do this is revealed here, using a variation of the Rough transform to detect circular patterns in a close shot of the eye. The algorithm was developed in Matlab and analyzed over a series of 20 sets of 6 …

Late Deflation Study : Hemodynamic Effects Of Iab Timing In Humans, Manal Morcos

Theses

Conventional IABP timing deflates 100% of the balloon volume before the onset of left ventricular ejection and has been well established in the literature as a safe and effective method. Yet, recent studies suggest that deflation of the IAB at or near the onset of systole improve myocardial efficiency (Kern, 1999, 1129). To test whether deflation of the JAB at a later deflation time reduces left ventricular workload and enhances coronary perfusion, four timing methods were evaluated in 20 patients: T₁ (100% JAB volume deflated before onset of ejection), T₂ (60% IAB volume deflated before and 40% volume …