Engineering Commons^™

A Comparative Study Of Monoclonal Antibodies (Mabs) Purified From Cell Culture Supernatant On Edtpa-Modified Zirconia Beads And Protein A-Hyper D Support, Anuradha Subramanian, Blanca Martinez, Jill Holm, Peter W. Carr, Clayton V. Mcneff

Papers in Biotechnology

Colloidal zirconia was spray dried to yield zirconia particles, which were further modified with N, N, N0, N0- Ethylenediamine tetra methylenephosphonic acid (EDTPA) to yield a sup-port for use in bioseparations. EDTPA modified zirconia particles will be further referred to as, r_PEZ. Cell culture supernatants rich in monoclonal antibody (Mab) subtypes IgG1, IgG2a, IgG2b, and IgG3 were chromatographed on a r_PEZ column, and on a protein A-hyper D col-umn that was purchased commercially. All Mab subtypes bound to r_PEZ and process yields in the range of 88 to 99% were obtained. The purity of the Mab products were ascertained by …

Improving Steering Module Efficiency For Incremental Loading Finite Element Numeric Models, Ryan L. Kitchen

Theses and Dissertations

Engineers frequently use computerized numeric models to calculate and predict water levels and current patterns for rivers, bays, and other bodies of water. This computation often involves an iterative process known as incremental loading that can cause frustration and consume a lot of time. Although the steering module in the Surface-water Modeling System (SMS) automates incremental loading to minimize user interaction, it can still be very time consuming. This thesis examines the steering module and the incremental loading process to improve its efficiency. Specifically, the RMA2 and FESWMS models are utilized. Two methods of improving efficiency are examined. The first …

Solid-State Impact-Ionization Multiplier, Hong-Wei Lee

Theses and Dissertations

This dissertation presents an innovative solid-state current amplifier based on impact-ionization. Unlike avalanche photodetectors which use the same amplification principle, this device can be integrated with any external current source. A discrete amplifier was built on a silicon surface using standard CMOS fabrication processes including lithography, oxidation, ion implantation, diffusion, chemical wet etching, metal deposition, annealing, and rapid thermal processing. Testing was performed by connecting the device to a silicon photodiode, indium-gallium-arsenide photodiodes, and a function generator to demonstrate its compatibility with arbitrary current sources. Current gains above 100 along with pre-amplified leakage currents of less than 10 nA were …

Analysis Of Surface Permanent Magnet Machines With Fractional-Slot Concentrated Windings, Ayman M. El-Refaie, Thomas M. Jahns, Donald W. Novotny

Electrical and Computer Engineering Faculty Research and Publications

This paper presents a closed-form analytical technique for analyzing surface PM machines equipped with fractional-slot concentrated windings. Since this class of winding configuration deviates significantly from conventional sinusoidal distributions, classical steady-state phasor or analytical techniques cannot be used to provide accurate results. The presented analytical model provides a fast and reliable method to analyze and compare candidate machine designs. Stator slotting effects are taken into consideration and a wide range of concentrated winding configurations can be analyzed. This technique is capable of analyzing the machine both below (constant-torque) and above (flux-weakening) base speed. Average torque, cogging torque, and ripple torque …

Improved Tool For Fingerspelling Recognition, Rosalee Wolfe, Nora Alba, Stacey Billups, Mary Jo Davidson, Cindy Dwyer, Diana Gorman Jamrozik, Lori Smallwood, Karen Alkoby, Lesley Carhart, Damien Hinkle, Amy Hitt, Brian Kirchman, Glenn Lancaster, John Mcdonald, Lindsay Semler, Jerry Schnepp, Brent Shiver, Anna Suh, Jeffrey Young

Visual Communications and Technology Education Faculty Publications

Conference proceedings from the Technology and Persons with Disabilities Conference-2006. California State University at Northridge, Los Angeles, CA March 20-25, 2006.

Human Interfaces For Cooperative Control Of Multiple Vehicle Systems, Jisang Sun

Theses and Dissertations

This thesis presents a human interface which helps users efficiently allocate multiple unmanned ground vehicles (UGVs) cooperating to accomplish timing-sensitive missions in an urban environment. The urban environment consists of obstacles and a hazardous region. The obstacles represent a "no-go zone" while the hazardous region represents a high-risk area. The main object of this problem is to minimize the team operational cost while satisfying timing constraints. Operational costs for individual vehicles are based on risk and power consumption, and are calculated using path length and vehicle velocity. In this thesis, three types of timing constraints are considered: simultaneous arrival, tight …

Encryption Of Computer Peripheral Devices, Kelly Robert Norman

Theses and Dissertations

Computer peripherals, such as keyboards, scanners, printers, cameras, and Personal Data Assistants (PDAs) typically communicate with a host PC via an unencrypted protocol, leaving them vulnerable to eavesdropping techniques, such as keyloggers. An encryption system was developed that is simple enough to be used in peripherals that do not have large amounts of processing power and memory. A software driver loaded in the operating system of the host computer communicates with a simple 8-bit microcontroller in the peripheral device. The driver handles key generation, key exchange, and provides decrypted data to the operating system. A key exchange protocol allows the …

Cracking And Roughness Of Asphalt Pavements Constructed Using Cement-Treated Base Materials, Jonathan Russell Hanson

Theses and Dissertations

While cement treatment is a proven method for improving the strength and durability of soils and aggregates, cement hydration causes shrinkage strains in the cement-treated base (CTB) that can lead to reflection cracking in asphalt surfaces. Cracking may then cause increased pavement roughness and lead to poor ride quality. The overall purpose of this research was to utilize data collected through the Long-Term Pavement Performance (LTPP) program to investigate the use and classification of CTB layers and evaluate the relative impact of cement content on the development of roughness and cracking in asphalt concrete (AC) pavements constructed using CTB layers. …

Risk-Based Decision Model For Determining The Applicability Of An Earned Value Management System In Construction, Mark D. Workman

Theses and Dissertations

New policy mandated by the Undersecretary of Defense for Acquisition, Technology and Logistics has lowered the dollar thresholds of contracts requiring earned value management (EVM). This policy directed that a "risk-based decision" be made to determine if EVM should be used on firm-fixed price contracts under $20 million. Although not previously applicable to Military Construction (MILCON) building projects or other Air Force Civil Engineer (CE) managed contracts, the new threshold requires that CE projects be evaluated for risk. Therefore, the focus of this research was to analyze the risk factors associated with construction contracts in an attempt to build a …

Technology Transition: Guidance Versus Practice, Walter E. Espy

Theses and Dissertations

The transition of technologies ensures that U.S. warfighters have the necessary capabilities to fight ever increasing and changing global threats. The purpose of this study is to discover to what extent the Air Force Research Laboratory (AFRL) is implementing known technology transition best practices. The research will look at the current guidance on technology transition and determine if it is being used by program managers within AFRL. The study will consider the technology transition process or processes expressly exercised within AFRL by surveying the perspectives and knowledge of program managers. An understanding of this process from the science and technology …

Risk Of Colon Cancer In Hereditary Non-Polyposis Colorectal Cancer Patients As Predicted By Fuzzy Modeling: Influence Of Smoking, Rhonda M. Brand, David D. Jones, Henry T. Lynch, Randall E. Brand, Patrice Watson, Ramesh Ashwathnayaran, Hemant K. Roy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

AIM: To investigate whether a fuzzy logic model could predict colorectal cancer (CRC) risk engendered by smoking in hereditary non-polyposis colorectal cancer (HNPCC) patients.

METHODS: Three hundred and forty HNPCC mismatch repair (MMR) mutation carriers from the Creighton University Hereditary Cancer Institute Registry were selected for modeling. Age-dependent curves were generated to elucidate the joint effects between gene mutation (hMLH1 or hMSH2), gender, and smoking status on the probability of developing CRC.

RESULTS: Smoking significantly increased CRC risk in male hMSH2 mutation carriers (P < 0.05). hMLH1 mutations augmented CRC risk relative to hMSH2 mutation carriers for males (P < 0.05). Males had a significantly higher risk of CRC than females for hMLH1 non smokers (P < 0.05), hMLH1 smokers (P < 0.1) and hMSH2 smokers (P < 0.1). Smoking promoted CRC in a dose-dependent manner in hMSH2 in males (P < 0.05). Females with hMSH2 mutations and both sexes with the hMLH1 groups only demonstrated a smoking effect after an extensive smoking history (P < 0.05).

CONCLUSION: CRC promotion by smoking in HNPCC patients is dependent on gene mutation, gender and age. …

The Art And Science Of Discontinuous Innovation: A Case Study In Product Reinvention, Daniel C. Smoot

Theses and Dissertations

Divergence of new and old technologies is a source of tremendous innovation potential. As the dizzying pace of technological innovation accelerates indefinitely into tomorrow, not only do new paths diverge exponentially; doors already opened are increasingly abandoned for the allure of things undiscovered. Mature, late-stage life-cycle products left behind in today's fast-paced world open the floodgates to reinvention. This paper tests the hypothesis that innovativeness can be encouraged through the learning and application of universal innovation principles and processes. The implications of this research area are far-reaching. If innovation can be encouraged, then it can likely be taught. If it …

Effect Of Co On No And N2o Conversions In Nonthermal Argon Plasma, Morris D. Argyle, Gui-Bing Zhao, Maciej Radosz

Faculty Publications

200-600 ppm of CO inhibit NO conversion in nonthermal Ar plasma, but do not produce N2O. However, 1.01% of CO has no effect on NO conversion, but produces N2O. In general, N2O conversion in Ar plasma decreases with increasing CO concentration. These experimental results cannot be explained by charge transfer reactions of Ar+. Selectivity analysis of all excited states of Ar possibly contributing to NOX conversion without and with CO suggests that only AR(3P2) contributes to NOX conversion and CO dissociation. A kinetic model of 43 reactions is required to model NO Conversion or N2O conversion in Ar without CO, …

The Role Of The Architect: Changes Of The Past, Practices Of The Present, And Indications Of The Future, Chad B. Jones

Theses and Dissertations

For centuries the architect was the master builder; the one who was responsible for both the design and the construction of a project with sufficient construction expertise to oversee the project from inception to completion. Eventually, complexity of projects required a higher level of specialization leading to the separation of the designer and the builder. Since that separation, the role of the designer, or architect, has continued to shift and evolve. In recent history, the architect has been the one selected by a building owner, at the inception of the project, as the professional who is able to assist and …

Automated Manipulation For The Lotus Filament Winding Process, Jeffrey V. Anderson

Theses and Dissertations

The filament-winding process produces quality consistent composite parts for many industries. Filament winding allows for consistent quality parts by automating the winding process. A recent development of filament winding is the Lotus process. The Lotus process reverses conventional filament winding by leaving the mandrel stationary and winding composite fiber around the mandrel. The automated Lotus filament-winding machine is controlled by four-axis control manipulating the Lotus ring around a fixed mandrel. This allows Lotus filament winding to wind parts that do not have a linear axis. Lotus filament winding is in its early stages of development. As a second step in …

Flight Testing Small, Electric Powered Unmanned Aerial Vehicles, Jon N. Ostler

Theses and Dissertations

Flight testing methods are developed to find the drag polar for small UAVs powered by electric motors with fixed-pitch propellers. Wind tunnel testing was used to characterize the propeller-motor efficiency. The drag polar was constructed using data from flight tests. The proposed methods were implemented for a small UAV. A drag polar was found for this aircraft with CDo equal to 0.021, K1 equal to 0.229, and K2 equal to -0.056. This drag polar was then used to find the following performance parameters; maximum velocity, minimum velocity, velocity for maximum range, velocity for maximum endurance, maximum rate of climb, maximum …

Analysis Of Viscous Drag Reduction And Thermal Transport Effects For Microengineered Ultrahydrophobic Surfaces, Jason W. Davies

Theses and Dissertations

One approach recently proposed for reducing the frictional resistance to liquid flow in microchannels is the patterning of micro-ribs and cavities on the channel walls. When treated with a hydrophobic coating, the liquid flowing in the microchannel wets only the top surfaces of the ribs, and does not penetrate into the cavities, provided the pressure is not too high. The net result is a reduction in the surface contact area between channel walls and the flowing liquid. For micro-ribs and cavities that are aligned normal to the channel axis (principal flow direction), these micropatterns form a repeating, periodic structure. This …

Optical Characterization Of Thick Growth Orientation-Patterned Gallium Arsenide, Joshua W. Meyer

Theses and Dissertations

Tunable laser sources in the mid-infrared (MIR) spectral range are required for several Air Force applications. Existing lasers with output in the near-infrared can be converted to more desirable MIR by using nonlinear effects. Orientation patterned gallium arsenide (OPGaAs) is a promising nonlinear conversion material because it has broad transparency and can be engineered for specific pump laser and output wavelengths using quasi-phase matching techniques. This research examines the optical quality of seven OPGaAs crystal samples and explores the design of an optical parametric oscillator (OPO) device. The Air Force Research Laboratory Electro-Optical Countermeasures Technology Branch obtained the samples from …

Investigation Of Copper Contamination And Corrosion Scale Mineralogy In Aging Drink Water Distributions Systems, Nadja F. Turek

Theses and Dissertations

Research has shown higher levels of copper appear in drinking water conveyed through relatively new copper piping systems; older piping systems typically deliver lower copper levels in their drinking water. This research contributes field data from a real drinking water distribution system, providing a better understanding of this phenomenon, as it relates to treatment considerations and compliance with the Lead and Copper Rule. Copper pipes and copper levels were sampled from drinking water taps of 16 buildings with pipes ranging in age from less than 1 to 48 years. Water samples from each building were collected before and following a …

Performance Analysis Of Mc-Cdma Communication Systems Over Nakagami-M Environments, Joy Iong-Zong Chen

Journal of Marine Science and Technology–Taiwan

The performance for a MC-CDMA (multi-carrier coded-division multiple-access) system working in uncorrelated and correlated fading channels with Nakagami distribution is investigated in this paper. We adopt the BPSK modulation scheme with an alternative expression for Q-function to evaluate the BER (bit error rate) performance of the MC-CDMA system. The sum of Gamma variates is adopted for deriving a closed-form solution for arbitrarily correlated channel in order to avoid the difficulty of explicitly obtaining the pdf (probability density function) for the SNR (signal-to-noise ratio) at the MRC (maximum ratio combining) output. The results with simple expression obviously show that the BER …

Two Dimensional Friction Stir Welding Model With Experimental Validation, Charles Blake Owen

Theses and Dissertations

The performance of a coupled viscoplastic model of FSW has been evaluated over a variety of tool RPMs and feed rates. Initial results suggested that further optimization of the material parameters and an additional ability to model the thermal recovery of the material would improve the overall performance of the model. Therefore, an experimental/numeric approach was taken to improve and quantitatively compare the performance of the model based upon the thermal profile of the workpiece. First, an experimental method for obtaining real-time temperature measurements during Friction Stir Processing (FSP) of 304L Stainless Steel was developed. The focus of the method …

Bearing Capacity Of Foundations On Sand Using The Method Of Slip Line, Meen-Wah Gui, Muhunthan

Journal of Marine Science and Technology–Taiwan

The accurate prediction of the bearing capacity of shallow foundations on granular soils has been complicated by their stress dependent strength behavior and the surface roughness of the foundationsoil interface. These are accounted for using empirical relations in the current state of practice. In this study, the stress dependent behavior of soils is accounted for using a strength dilatancy relationship. The method of slip line has been extended to incorporate this relationship and the effects of surface roughness to derive the depth dependent bearing capacity factor Nq. The results are presented in terms of angle of friction, depth/diameter ratio, and …

Experimental Study On The Performance Of Ship Fire Protection Materials, Jen-Chieh Lee, Shi-Jie Liu

Journal of Marine Science and Technology–Taiwan

The performance of heat insulation, sound absorption and insulation of ship fire protection materials is experimentally investigated in this paper. The fire protection materials of rock wool 60 k (60 kg/m3 ) and ceramic fiber 80k (80 kg/m3 ) are tested to show the requisite minimum thickness for the regulation of IMO heat insulation A class. The results show that the heat insulation performance of ceramic fiber (25 mm) and rock wool (50 mm) meets the requirement of A-30 class bulkhead. However, the composition of ceramic fiber (25 mm) and rock wool (25 mm) with the ceramic fiber exposed to …

State Variance Constrained Fuzzy Control Via Observer-Based Fuzzy Controllers, Wen-Jer Chang, Balasingam Yeh, Yu-Teh Meng

Journal of Marine Science and Technology–Taiwan

In this paper, a state variance constrained design method is developed to deal with the observer-based fuzzy control problem for continuous Takagi-Sugeno (T-S) fuzzy stochastic models. The stability problem considered in this paper is a standard feasibility problem with several Linear Matrix Inequalities (LMIs), which can be solved numerically using the interior-point method. The purpose of this paper aims at finding observer-based fuzzy controllers such that the closed-loop system is asymptotically stable and the state variance performance constraints are satisfied. Finally, a numerical example is included to demonstrate the effectiveness of the proposed controller design method.

Co2-Selective Membranes Containing Amino Groups, W.S. Winston Ho

Chemical and Materials Engineering Faculty Patents

Novel compositions suitable for fabrication of CO₂-selective membranes are disclosed. In one aspect, the present invention is directed to compositions comprising polyimide/polyamine blends and copolymers, and to compositions comprising interfacially polymerized polyamides. In another aspect this invention is directed to novel CO₂-selective membranes comprising such polyimide/polyamine blends and copolymers, and to novel CO₂-selective membranes comprising interfacially polymerized polyamides. In yet another aspect, the present invention is directed to a novel water-gas-shift (WGS) reactor comprising the novel CO₂-selective membranes. Advantageously, the use of the novel CO₂-selective membrane allows alteration of the …

Packet-Switching Network With Symmetrical Topology And Method Of Routing Packets, Nader F. Mir

Electrical and Computer Engineering Faculty Patents

A mesh network for routing a plurality of data segments therethrough, each of the data segments containing address information. The network includes: a first, second, and third switch element each having a respective external input for routing data segments into the network and a respective external output for routing data segments out of the network; a bi-directional coupling between each of the switch elements; and a first controller for interrogating the address information of each of the data segments inbound into the first switch element. The exit pathway for any inbound data segment received by a switch element is selected …

Assessing The Potential For Improved Scramjet Performance Through Application Of Electromagnetic Flow Control, Martin F. Lindsey

Theses and Dissertations

Hypersonic flight using scramjet propulsion bridges the gap between turbojets and rockets. Recent efforts focus on magnetogasdynamic (MGD) flow control to mitigate the problems of high thermomechanical loads and low efficiencies associated with scramjets. This research is the first flight-scale, three-dimensional computational analysis of a realistic scramjet to assess how MGD flow control improves scramjet performance. Developing a quasi-one dimensional design tool culminated in the first open source scramjet geometry. This geometry was tested with the Air Force Research Laboratory's electromagnetic computational code. To increase fidelity, an algorithm was developed to incorporate thermochemistry, resulting in the only open-source model of …

Modeling Study To Quantify The Benefits Of Groundwater Contaminant Source Remediation, David E. Wagner

Theses and Dissertations

The purpose of this research was to quantify the benefits of groundwater contaminant source remediation by using a model to simulate how reduction of source mass was related to reduction of contaminant concentration at a receptor. This thesis sought to answer three research questions: (1) how are contaminant source mass reduction and reduction of mass flux leaving the source-zone related; (2) how can we quantify the effect of the important natural attenuation processes that act upon the dissolved contaminant as it travels from the source zone to downgradient receptors, and (3) under specified site conditions, what is the maximum contaminant …

Analysis And Simulation Of Hypervelocity Gouging Impacts, John D. Cinnamon

Theses and Dissertations

In this work, a summary of past and present research efforts, as well as the theoretical foundation, of hypervelocity gouging is presented. As the Holloman AFB High Speed Test Track (HHSTT) sled's speed has increased to Mach 8.5, material interactions develops which causes "gouging" - this can result in catastrophic failure. A characterization of gouging, including a thermodynamic history, is developed from an examination of a gouged rail. An extensive study is performed that determines the specific material flow models for VascoMax 300 and 1080 steel. The models are validated utilizing several experimental tests which are successfully simulated using CTH …

Characterization Of Stress In Gan-On-Sapphire Microelectromechanical Systems (Mems) Structures Using Micro-Raman Spectroscopy, Francisco E. Parada

Theses and Dissertations

Micro-Raman (µRaman) spectroscopy is an efficient, non-destructive technique widely used to determine the quality of semiconductor materials and microelectromechanical systems. This work characterizes the stress distribution in wurtzite gallium nitride grown on c-plane sapphire substrates by molecular beam epitaxy. This wide bandgap semiconductor material is being considered by the Air Force Research Laboratory for the fabrication of shock-hardened MEMS accelerometers. µRaman spectroscopy is particularly useful for stress characterization because of its ability to measure the spectral shifts in Raman peaks in a material, and correlate those shifts to stress and strain. The spectral peak shift as a function of stress, …