Engineering Commons^™

A Study Of The Security Implications Involved With The Use Of Executable World Wide Web Content, Christopher Hu

Theses: Doctorates and Masters

Malicious executable code is nothing new. While many consider that the concept of malicious code began in the 1980s when the first PC viruses began to emerge, the concept does in fact date back even earlier. Throughout the history of malicious code, methods of hostile code delivery have mirrored prevailing patterns of code distribution. In the 1980s, file infecting and boot sector viruses were common, mirroring the fact that during this time, executable code was commonly transferred via floppy disks. Since the 1990s email has been a major vector for malicious code attacks. Again, this mirrors the fact that during …

Finite Element Analysis And Testing Of An Inkjet Cartridge Die, Dylan Ryan

Theses

This project investigates the application of finite element and experimental analysis in the design and testing of silicon based semiconductor components. In a thermal inkjet printer the ink cartridge contains a print head (or die), the head fires numerous droplets simultaneously to form pixels and letters. The inkjet cartridge die consists of a thin film layer, containing the integrated circuits that make up the thennal inkjets, mounted on a polysilicon substrate structure.

A number of incremental changes to the design and manufacturing processes related to the manufacture of these inkjet cartridge dies is made. In past instances when changes were …

Dynamically Biased Radio Frequency Power Amplifier, Tom Twomey

Theses

With the current trend in mobile communications towards more complex modulation schemes to enhance spectral efficiency, the design of RF power amplifiers is the subject of considerable interest and research. The newer more spectrally efficient modulation schemes require a much higher level of linearity due to the non-constant level of their signal envelope. A variable envelope signal would in non-linear amplifiers lead to unacceptable levels of distortion. Linear amplifiers solve this problem at the cost of significant loss of efficiency. With the evolution towards more spectrally efficient modulation schemes, the trade off between linearity and power efficiency has become more …

Analysis Of Cooling And Heating Of Water With Flat-Plate Solar Radiators, Igor Balen, Vladimir Soldo, David Kennedy

Conference Papers

Extensive analysis of flat-plate radiative panels operation using average hourly weather data for a maritime climate region was performed. The panels are integrated in the space ventilation system with air-cooling by means of a cold-water coil. Their primary function is to prepare sufficient quantity of cold water, integrating radiative and convective cooling, that is collected in the cold-water tank during the nighttime operation. That cold water is used for cooling of the air during daytime. By small modification during daytime, solar panels could be turned into collectors and used to produce the hot water that is collected in a separate …

Solution Of The Navier-Stokes Equations For Transonic Propeller Flows, Fergal Boyle

Conference Papers

The three-dimensional, compressible, viscous flow field around a general propeller geometry with the inflow at zero angles of incidence and yaw is computed using a Reynolds-Averaged Navier-Stokes equations solver. Results from validation test cases in which the laminar and turbulent incompressible flow over a flat plate are calculated demonstrate the flow solver is capable of accurately capturing boundary-layer behaviour. Euler solutions from flow field calculations around two very different propeller geometries show a high level of accuracy and efficiency. Preliminary results from a viscous flow field calculation around a two-bladed propeller are very encouraging.

Development Of A Training Program In Lean Manufacturing, Alok K. Verma, James Hughes

Engineering Technology Faculty Publications

Lean Manufacturing is quickly becoming a philosophy adopted by manufacturer's through out the world to cut out waste and improve productivity. Lean is a people-centric philosophy, which focuses on changing the work-culture within an organization and across the supply chain. Thus, training the work force in lean principles is a major part of any lean implementation. This paper presents the development of a lean training program for the Apprentice School at Northrop Grumman Newport News. The instructional pedagogy relies on both classroom instruction and hands-on simulation activity to relay lean concepts to students. The training program is being incorporated into …

Compact Supercell Method Based On Opposite Parity For Bragg Fibers, Wang Zhi, Ren Guobin, Lou Shuquin, Liang Weijun, Shangping Guo

Electrical & Computer Engineering Faculty Publications

The supercell- based orthonormal basis method is proposed to investigate the modal properties of the Bragg fibers. A square lattice is constructed by the whole Bragg fiber which is considered a supercell, and the periodical dielectric structure of the square lattice is decomposed using periodic functions (cosine). The modal electric field is expanded as the sum of the orthonormal set of Hermite-Gaussian basis functions based on the opposite parity of the transverse electric field. The propagation characteristics of Bragg fibers can be obtained after recasting the wave equation into an eigenvalue system. This method is implemented with very high efficiency …

Numerical Techniques For Excitation And Analysis Of Defect Modes In Photonic Crystals, Shangping Guo, Sacharia Albin

Electrical & Computer Engineering Faculty Publications

Two numerical techniques for analysis of defect modes in photonic crystals are presented. Based on the finite-difference time-domain method (FDTD), we use plane wave incidences and point sources for excitation and analysis. Using a total-field/scattered-field scheme, an ideal plane wave incident at different angles is implemented; defect modes are selectively excited and mode symmetries are probed. All modes can be excited by an incident plane wave along a non-symmetric direction of the crystal. Degenerate modes can also be differentiated using this method. A proper arrangement of point sources with positive and negative amplitudes in the cavity flexibly excites any chosen …

Micro Molding Of 3 D Ceramic Parts, Dinakar Palaparti

LSU Master's Theses

The objective of this research was to manufacture and evaluate three-dimensional (3D) ceramic parts with microstructures, characterize the ceramic injection molding process used for it along with fabrication and evaluation of various mold insert formats, electroplated patterns and X-ray masks used in the process. The patterns were electroplated in nickel on two formats of mold insert substrates. The first format was a modified 1” diameter stainless/tool steel plug suitable for test structures and for complete penetration by melt during injection. The molding was done by CoorsTekâ (Golden CO) as they possessed the required wherewithal and the mold base. The second …

Modeling And Evaluating Evacuation Contraflow Termination Point Designs, Yu Yik Lim

LSU Master's Theses

Prior studies showed that most evacuation contraflow designs have never been implemented. As a result, the effectiveness of these contraflow termination point designs remains unknown. To address this problem, a microscopic traffic simulation tool, CORSIM 5.0, was used. Ten simulation models were conducted and determined the factors that affect traffic operations in the vicinity of the various planned contraflow termination point with median crossover designs. The performance of various models was ranked by statistical test in terms of the total number of vehicles processed, traffic flow, speed, density and delay. The results that were based on theoretical simulations and assumptions …

Design Of Optimal Equalizers And Precoders For Mimo Channels, Lijuan Li

LSU Doctoral Dissertations

Channel equalization has been extensively studied as a method of combating ISI and ICI for high speed MIMO data communication systems. This dissertation focuses on optimal channel equalization in the presence of non-white observation noises with unknown PSD but bounded power-norm. A worst-case approach to optimal design of channel equalizers leads to an equivalent optimal H-infinity filtering problem for the MIMO communication systems. An explicit design algorithm is derived which not only achieves the zero-forcing (ZF) condition, but also minimizes the RMS error between the transmitted symbols and the received symbols. The second part of this dissertation investigates the design …

Treatment Of Mixtures Of Methyl Ethyl Ketone (Mek) And Toluene Using Continuous And Sequencing Batch Operated Biofilters, Jorge C. Atoche

LSU Master's Theses

During the past decade, biofiltration has increasingly been applied as an air pollution control technology to minimize or eliminate emissions of volatile organic compounds from industrial sources. Although of the ability of this technology to maintain high removal efficiency during relatively steady conditions has been well established for many waste streams, a limitation of this technology has been its inability to maintain high removal efficiency during transient loading conditions typical of industrial operations. In the research described herein, a conventional continuous-flow biofilter (CFB) and a sequencing batch biofilter (SBB) were operated for more than 295 days to treat a model …

Minimization Of Power Losses In Active Magnetic Bearing Control, Nader Motee

LSU Master's Theses

A solution to the problem of AMB control with reduced electrical power losses will be presented in this thesis. The proposed control solution will be founded on the integrator backstepping technique, which decouples the rotor stabilization problem from the bias flux design problem. It further allows for the easy redesign of the control law to compensate for uncertainties in the AMB system. A class of nonlinear controllers will be developed that reduces the AMB power losses in comparison to standard fixed-bias controllers, while containing no control singularity. Control laws will be presented for the standard AMB operating mode where both …

A Screening Assessment Of Solidification/Stabilization For Storm Water Residuals, Erin Ezell Krielow

LSU Master's Theses

Metal species infused particulate matter associated with urban rainfall-runoff is a unique and profuse source of pollution. Generated from urban activities, such as traffic activity and vehicular/infrastructure abrasion, contaminated residual material is deposited to roadways during dry weather and transported to surrounding environments and/or best management practice (BMP) treatment facilities during wet-weather events. These particulates range in size from 1 ƒÝm to 10000 ƒÝm and are contaminated with metal species that originate from such sources as vehicular body wear (Cu), tire wear (Zn), and brake dust (Pb). Depending on the efficiencies of the BMP treatment facilities, these containment systems have …

Biomechanical Effects Of Cyclic Loading On The Lower Back, Lakiesha Claude

LSU Master's Theses

More than 30 million people in the United States may have low back pain at any time, and 10 million of them have chronic symptoms. Epidemiological studies indicate that along with axial compressive loads, other factors including repetitive twisting or lateral bending and lifting are significant risk factors for low-back disorders. Literature repeatedly confirms that cyclic occupational functions expose workers to a 10-fold increase in episodes of low back injury and pain. This study examined the biomechanical effects of cyclical loading on the lower back. Twenty in vivo feline preparations were subjected to passive cyclic loading at 20 N (n=6), …

The Rapid Template Fabrication Process For Producing A Liga Heat Exchanger Bonded To A Mechanical Seal, Jason Patrick Tuma

LSU Master's Theses

Mechanical seals are widely used in the chemical processing, aerospace, and automotive, industries. When a mechanical seal fails, considerable cost is typically involved in replacing the seal. Most seal failures are a result of high temperatures generated by frictional heating. Effectively removing the heat generated would significantly increase the mechanical seal’s work life and lead to significant monetary savings. One method of removing the heat generated is bonding an effective LIGA micro heat exchanger to the mechanical seal and forcing coolant through the heat exchanger. Previous work on this subject revealed promising results, especially for micro heat exchangers with microstructures …

A Methodology For Deriving Performance Measures From Spatio-Temporal Traffic Contour Maps Using Digital Image Analysis Procedures, Prashanth Kotha

LSU Master's Theses

The main focus of this study is to improve the data analysis tools used in performance monitoring and level of service assessment of freeway systems. The proposed study presents a methodology to develop new second-order statistical measures that are derived from texture characterization techniques in the field of digital image analysis. The new measures are capable of extracting properties such as smoothness, homogeneity, regularity, and randomness in traffic behavior from the spatio-temporal traffic contour maps. To study the new performance measures a total of 14270, 15-min traffic contour maps were generated for a section of 3.4 miles of I-4 in …

On Implementing Dynamically Reconfigurable Architectures, Hatem Mahmoud El-Sayed El-Boghdadi

LSU Doctoral Dissertations

Dynamically reconfigurable architectures have the ability to change their structure at each step of a computation. This dissertation studies various aspects of implementing dynamic reconfiguration, ranging from hardware building blocks and low-level architectures to modeling issues and high-level algorithm design. First we derive conditions under which classes of communication sets can be optimally scheduled on the circuit-switched tree (CST). Then we present a method to configure the CST to perform in constant time all communications scheduled for a step. This results in a constant time implementation of a step of a segmentable bus, a fundamental dynamically reconfigurable structure. We introduce …

Modeling A Mississippi River Diversion Into A Louisiana Wetland, Stephan Alexander Capps

LSU Master's Theses

Wetland loss has significant impacts. Numerous loss mechanisms have been hypothesized, and a greater number of solutions have been proposed. One proposed solution is to divert river water into a degraded area with the intent of increasing sedimentation, introducing nutrients, and/or decreasing salinity within the wetland. However, wetland hydraulics and hydrology are complex processes and any hydrologic modification may result in unintended consequences. Predicting these consequences can be problematic due to the complexity and difficulty associated with proper modeling of the hydraulics and topography. The primary objective of this study is to evaluate the suitability of established one- and two-dimensional …

The Fate Of Nitrogen In The Marshland Upwelling System, Jeremy Fontenot

LSU Master's Theses

The Marshland Upwelling System (MUS) is an alternative method for coastal dwellers to treat their wastewater. Past studies have dealt with the removal of fecal pathogens from wastewater. However the objectives of this research were to: 1) evaluate the treatment capability of the MUS under high hydraulic loadings and cool temperatures with respect to CBOD₅, TKN, TAN, NO₂^--N, NO₃^--N, TP, and PO₄-P, and 2) determine the ideal flowrate and injection frequency to achieve satisfactory nitrogen removal without hydraulic failure. The artificial wastewater study was performed to evaluate the treatment of …

Generalized D-Sequences And Their Applications To Cdma Systems, Radhika Vaddiraja

LSU Master's Theses

Code Division Multiple Access (CDMA), a form of spread spectrum communications is used widely in cellular telephony. CDMA systems employ Walsh-Hadamard orthogonal codes, jointly with Pseudo-Noise (PN) sequences, Gold sequences and Kasami sequences to achieve spreading. This thesis investigates properties of generalized d-sequences and their applications as spreading sequences in CDMA systems. The correlation properties of these sequences are studied. The autocorrelation function of these sequences is not exactly two-valued but the cross correlation values are zero for certain class of these sequences. The zero cross correlation property can be useful in solving the near-far problem in CDMA communication systems, …

Optimal Batch Quantity Models For A Lean Production System With Rework And Scrap, Pablo Biswas

LSU Master's Theses

In an imperfect manufacturing process, the defective items are produced with finished goods. Rework process is necessary to convert those defectives into finished goods. As the system is not perfect, some scrap is produced during this process of rework. In this research, inventory models for a single-stage production process are developed where defective items are produced and reworked, where scrap is produced, detected and discarded during the rework. Two policies of rework processes are considered (a) First policy: rework is done within the cycle, and (b) Second policy: rework is done after N cycles of normal production. Also, three types …

Advanced Turbulence Modeling For Industrial Flows, Raymond Michael Jones

LSU Doctoral Dissertations

This dissertation deals with the development of an improved two-equation turbulence model and its application to various flows. Six different conventional turbulence models were initially tested for predicting the flow inside of an unbaffled stirred tank reactor (STR), and the results are compared with experimental LDV data. Each of the models use low Reynolds number corrections. Results indicate that the radial velocity component in the impeller discharge region is overpredicted by each of the models. The tangential velocity component in the impeller discharge region is predicted well by the models, but is underpredicted near the shaft. The low Reynolds number …

Removal Of Sustained Casing Pressure Utilizing A Workover Rig, Kevin Soter

LSU Master's Theses

This thesis will analyze the techniques used during the 1989 and 1990 workover programs as well as subsequent operations in 1991/1992. It will also present the techniques and results of the most recent 1999 workover program undertaken to alleviate the most persistent sustained casing pressure (SCP) in a mature Gulf of Mexico field. An extensive literature review is included to better illustrate the complexity of the issues involved and possible SCP mechanisms. The field was drilled during the 1980’s and SCP has been prevalent in some cases previous to initial completion operations. Previous remedial programs resulted in limited success in …

Contraflow Evacuation On The Westbound I-10 Out Of The City Of New Orleans, Gregoris Theodoulou

LSU Master's Theses

In this study, CORSIM 5.0 simulation model results were used to evaluate the effectiveness of the contraflow segment on westbound I-10 out of the City of New Orleans. The Louisiana State Police plan for the contraflow segment was used to construct the CORSIM network. Alternative plans were also developed in this study to compare the effectiveness of the contraflow operation. With the use of CORSIM, traffic flow on the contraflow segment was determined based on the amount of evacuating vehicles leaving the exit nodes. In addition the time and speed to travel the contraflow segment was estimated. The results showed …

Design, Development, And Analysis Of A Twin-Fluid Fire Suppression Atomizer And Characterization Of Electrostatically Charged Droplet Sprays, Chad Everett Moore

LSU Master's Theses

A twin-fluid water mist fire suppression atomizer is designed, developed, and analyzed. Of primary interest is the development of a twin-fluid atomizer that produces a large droplet diameter and velocity distribution and also produces a mist with sufficient cone angle to be effective in fire suppression applications. Spray characterization experiments are conducted utilizing Phase Doppler Particle Analysis (PDPA). The effect of atomizer nozzle geometry on internal two-phase flow and resulting spray pattern is investigated. National Fire Protection Association (NFPA) Standard 750 characterization experiments are conducted to verify that the sprays produced by the developed atomizer are classified as a water …

Assessing Sample Bias And Establishing Standardized Procedures For Weighting And Expansion Of Travel Survey Data, Fahmida Nilufar

LSU Master's Theses

Recent household travel surveys are encountering problems with non-response, non-coverage, non-reporting, and even incorrect or incomplete reporting of trips. In addition, data from survey samples are affected by the social, and economic conditions of the respondents, as well as the survey instrument used to collect the data. As a result, household travel survey data are invariably associated with some level of bias. These threats to the integrity of the data are often ignored while analyzing the sample survey data. However, considering the importance of information derived from such surveys, it is necessary that the survey must provide an accurate reflection …

A Novel Hydrogen And Oxygen Generation System, Zhiyong Peng

LSU Master's Theses

This study examined the three phases of the sorption-enhanced SMR process for H2 production: production of low-CO hydrogen using the standard Ni-based reforming catalyst and high purity CaO sorbent precursor, evaluation of combined reforming catalyst-sorbent samples supplied by TDA, and an Aspen simulation study of the process for simultaneous production of H2 and O2. The production of low-CO (<20ppmv) hydrogen was studied using the single-step sorption-enhanced steam methane reforming process. The effects of temperature, volumetric feed rate, and feed gas composition on the purity of H2 and the content of CO were investigated. The feasibility of producing 95+% H2 with CO content of less than 20ppmv was experimentally proven in a test at 480¡ãC and 5 atm using a commercial Ni-based catalyst and the calcium-based CO2 sorbent. The feed gas contained 20% CH4 and 80% H2O, while the product gas contained 97.8% H2 and 17 ppmv CO. With this low CO concentration, the product can be used in a proton exchange membrane (PEM) fuel cell without further purification. The catalyst-sorbent samples from TDA Research Inc. were extensively studied and evaluated with respect to their performance in the steam-reforming reaction using both the fixed-bed reactor system and TGA. The activity of the catalyst samples having different compositions was examined and compared at different temperatures and space velocities using a feed gas containing 11.1% CH4 with a steam-to-carbon (S/C) ratio of 3.0. The sorption activity and durability was also examined in the TGA system. The overall hydrogen and oxygen co-production process was studied and evaluated using the Aspen Plus simulator. Material and energy balance calculations showed that this system can produce 99+% purity hydrogen and oxygen simultaneously with efficient energy integration. This process is balanced on power consumption and generation, so no external power is required.

Experimental Evaluation Of Temporal Particle Agglomeration And Metal Partitioning Of Urban Rainfall-Runoff, Aimee Ann Blazier

LSU Master's Theses

Rainfall-runoff quantity and quality control presents unique challenges due to the complexity and variability of hydrology and rainfall-runoff chemistry as well as the variable nature of constituent-producing processes in the environment. This study investigates two fundamental processes in rainfall-runoff: temporal particle agglomeration and metal partitioning between the solid and aqueous phase. A series of rainfall-runoff events were captured at an urban, Portland concrete cement (PCC) paved site in Baton Rouge, Louisiana and characterized with respect to particle gradation and metal phase fractions (dissolved and particulate) over time from a well-mixed, batch experimental system. Results indicate that equilibria and kinetics of …

Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez

LSU Doctoral Dissertations

Maintaining underbalanced conditions from the beginning to the end of the drilling process is necessary to guarantee the success of jointed-pipe underbalanced drilling (UBD) operations by avoiding formation damage and potential hazardous drilling problems such as lost circulation and differential sticking. However, maintaining these conditions is an unmet challenge that continues motivating not only research but also technological developments. This research proposes an UBD flow control procedure, which represents an economical method for maintaining continuous underbalanced conditions and, therefore, to increase well productivity by preventing formation damage. It is applicable to wells that can flow without artificial lift and within …