Engineering Commons^™

Voice Activated Display Of American Sign Language For Airport Security, Glenn Lancaster, Karen Alkoby, Jeff Campen, Roymieco Carter, Mary Jo Davidson, Dan Ethridge, Jacob Furst, Damien Hinkle, Bret Kroll, Ryan Layesa, Barbara Loeding, John Mcdonald, Nedjla Ougouag, Jerry Schnepp, Lori Smallwood, Prabhakar Srinivasan, Jorge Toro, Rosalee Wolfe

Visual Communications and Technology Education Faculty Publications

Conference proceedings from the Technology and Persons with Disabilities Conference-2003.

California State University at Northridge, Los Angeles, CA March 17-22, 2003.

Sem/Eds Observations Of Impurities In Polar Ice: Artifacts Or Not?, Ian Baker, Daniel Cullen

Dartmouth Scholarship

A series of experiments was undertaken to determine the origin of filaments found in grain boundaries and impurity spots found in grain interiors of polar ice during observation in the scanning electron microscope. It is shown that although the filaments are artifacts, they demonstrate the presence of impurities segregated to the grain boundary planes. It is also demonstrated that the impurities observed in the grain interior reside there and were not transported from the grain boundaries during specimen preparation or observation.

An Iterative Loop Matching Approach To The Prediction Of Rna Secondary Structures With Pseudoknots, Jianhua Ruan, Weixiong Zhang

All Computer Science and Engineering Research

Motivation: Pseudoknots have generally been excluded from the prediction of RNA secondary structures due to the difficulty in modeling and complexity in computing. Although several dynamic programming algorithms exist for the prediction of pseudoknots using thermodynamic approaches, they are neither reliable nor efficient. On the other hand, comparative methods are more reliable, but are often done in an ad hoc manner and require expert intervention. Maximum weighted matching (Tabaska et. al, Bioinformatics, 14:691-9, 1998), an algorithm for pseudoknot prediction with comparative analysis, suffers from low prediction accuracy in many cases. Here we present an algorithm, iterative loop matching, for predict-ing …

Angular Dependence Of Magnetization Reversal Process In Exchange Coupled Ferromagnetic/Antiferromagnetic Bilayers, Z.Y. Liu, Shireen Adenwalla

Materials Research Science and Engineering Center: Faculty Publications

The angular dependence of the magnetization reversal process in the exchange biased ferromagnetic/antiferromagnetic bilayers has been investigated carefully using the Stoner–Wohlfarth rotation model. Depending strongly on the orientation of the applied field and the competition between the unidirectional and uniaxial anisotropic energies, the magnetization rotation can occur at either the same side or the different sides of the field direction for the decreasing and increasing field branches of the hysteresis loop. The calculated results and the magneto-optical Kerr effect have been used to understand the magnetization reversal process in the NiFe/NiO bilayers, which is caused mainly by the magnetization rotation.

Dynamics Of Asymmetric Nonlinear Vibration Absorber, Chiou-Fong Chung, Chiang-Nan Chang

Journal of Marine Science and Technology–Taiwan

A dynamics of stability and bifurcation analysis of an asymmetrically nonlinear absorber system that contains a main part and a nonlinear spring is proposed. For this study, the analytical works on this nonlinear vibration absorber were performed by the harmonic balance method and the Floquet theory. Dynamic phenomena due to changing of periodic excitation are analyzed. The investigation fulfils that the bifurcation sequences illustrate completely the complex phenomena of system dynamics. Furthermore, this study show that the primary bifurcation orbit coexist with orbit of the secondary responses via a saddle-node bifurcation in a specific period excitation range. The results demonstrate …

Mathematical Modeling And Applications For Concrete Carbonation, Ming-Te Liang, Shieng-Min Lin

Journal of Marine Science and Technology–Taiwan

A new concept, carbon dioxide (CO2) transport in concrete, is proposed in this paper to describe solute-transport processes. Using this concept, a new one-dimensional mathematical model was developed to describe the transport phenomena of carbon dioxide in concrete structures. By treating transport phenomena as a concrete carbonation process, a one-dimensional linear partial differential equation was derived based on the principle of mass balance and convective-dispersive equation and was found the analytical solution by the separation of variables and the Laplace transform methods combined with some substitution approaches. The concrete carbonation numerical results were determined using parameters, such as the diffusion …

Study On Vortex-Excited Nonlinear Vibration Of Casing Pipes In Wave-Current, You-Gang Tang, Jian-Qin Min, Hong-Yu Zheng, Jia-Yang Gu

Journal of Marine Science and Technology–Taiwan

The vortex-induced nonlinear vibration of casing pipes in the deep water is studied considering the loads of current and combined wave-current. The vortex-induced vibration equation of a casing pipe is set up with considering the beam mode and Morison's nonlinear fluid damp as well as the vortex-excited loads. The approach of calculating vortex-excited nonlinear vibration by Galerkin's method is proposed. The natural vibration characteristics and the vortexexcited vibration response of 170m long casing pipe in the 160m depth of water are investigated, the resonance induced by wave and the resonance under combined wave-current were investigated, which is shown that the …

Data Compression Applied To Electric Power Quality Tracking Of Arc Furnace Load, Chi-Jui Wu, Tsu-Hsun Fu

Journal of Marine Science and Technology–Taiwan

The data compression techniques are used to enhance the storage capability of electric power quality instruments in monitoring distorted waveforms of electric arc furnaces. Both voltage flicker in voltage waveforms and harmonic components in current waveforms are major disturbances. The compression approaches by multiresolution analysis developed from the discrete wavelet transform with threshold coding and vector quantization coding are compared. The results from spectrum analysis show high compression ratios while keep low information loss. The error levels between original and reconstructed waveforms are discussed. Field measured waveforms from arc furnace loads are used to show the goodness of the data …

Study On The Vibration Reduction Of The Double Pistons Hydraulic Engine Mount, You-Gang Tang, Hong-Yu Zheng, Jia-Yang Gu, Da-Ning Jiang

Journal of Marine Science and Technology–Taiwan

A novelty style metal hydraulic engine mount (HEM) is developed. The HEM designed in this paper consists of hydraulic cylinder, bar, two pistons and the spring on the bottom. The mechanical model and the dynamic equations are set up by considering kinematics and continuous of fluid, and the analytical method for dynamic behavior including dynamic stiffness and transfer function of HEM are suggested herein. The dynamic characteristics of HEM are investigated. It is shown that the HEM proposed herein can be employed in the practical engineering for vibration reduction.

Port Competitiveness Evaluation By Fuzzy Multicriteria Grade Classification Model, Wen-Chih Huang, Junn-Yuan Teng, Miin-Jye Huang, Ming-Shin Kou

Journal of Marine Science and Technology–Taiwan

Competitiveness measurement of ports should be different from business/enterprises of the private sector. It needs to consider operational efficiency and overall effectiveness. Therefore, this paper attempts to establish a multi-criteria evaluation model. We develop Fuzzy Multi-criteria Grade Classification (FMGC) model to serve the purpose. This model is primarily for qualitative analysis, but this study invites quantitative indicators. It concurrently takes efficiency and effectiveness indicators into consideration. FMGC evaluates port competitiveness classification by partial order based on five grades. Partial order is sufficient to present superiority of port competitiveness. This paper takes eight East Asian container seaports for empirical study, also …

Political Authority And Social Cognitions On The War On Terrorism With Global Reach: Airport Security, Terrorism Contingent On A United States-Led Attack On Iraq, Smallpox Vaccinations, Ibpp Editor

International Bulletin of Political Psychology

This article presents analyses of three common social cognitions embraced by many representatives of political authority concerning aspects of the war on terrorism with global reach.

Electrical Activation Studies Of Silicon Implanted Alx Gal-X N And Coimplanted Gan, Elizabeth A. Chitwood

Theses and Dissertations

A comprehensive study of the electrical activation of silicon implanted Al_xGa_1-xN was performed as a function ion dose, anneal temperature, and aluminum mole fraction, Also, GaN coimplanted with silicon and nitrogen was investigated. Room temperature Hall effect measurements were used to determine carrier concentration and mobility. All the samples had a 500 Å encapsulant of AlN, and were implanted at room temperature with 200 keV silicon ions at doses ranging from 1x10¹³ to 1x10¹⁵ /sq cm. The GaN was also implanted with nitrogen under the same conditions in doses of 9x10¹² to 9x10 …

Channel Probing For An Indoor Wireless Communications Channel, Brandon Hunter

Theses and Dissertations

The statistics of the amplitude, time and angle of arrival of multipaths in an indoor environment are all necessary components of multipath models used to simulate the performance of spatial diversity in receive antenna configurations. The model presented by Saleh and Valenzuela, was added to by Spencer et. al., and included all three of these parameters for a 7 GHz channel. A system was built to measure these multipath parameters at 2.4 GHz for multiple locations in an indoor environment. Another system was built to measure the angle of transmission for a 6 GHz channel. The addition of this parameter …

Stability Of Order In Solvent-Annealed Block Copolymer Thin Films, Sanjun Niu, Ravi F. Saraf

Papers in Nanotechnology

ABSTRACT: One way to produce high order in a block copolymer thin film is by solution casting a thin film and slowly evaporating the solvent in a sealed vessel. Such a solvent-annealing process is a versatile method to produce a highly ordered thin film of a block copolymer. However, the ordered structure of the film degrades over time when stored under ambient conditions. Remarkably, this aging process occurs in mesoscale thin films of polystyrene-polyisoprene triblock copolymer where the monolayer of vitrified 15 nm diameter polystyrene cylinders sink in a 20 nm thick film at 22 °C. The transformation is studied …

Luminescence Studies Of Ion-Implanted Gallium Nitride And Aluminum Gallium Nitride, Erin N. Claunch

Theses and Dissertations

Recently, research on the wide bandgap semiconductors such as GaN and Al(x)Ga(1-x)N became very popular for their applications on various devices. Therefore comprehensive and systematic luminescence studies of Si implanted Al_xGa_1-xN, Mg doped GaN, and Si+N implanted GaN grown on sapphire substrates by molecular beam epitaxial method have been made as a function of ion dose and anneal temperature.

Stress Corrosion Cracking Of Type 422 Stainless Steel For Applications In Spallation-Neutron-Target Systems, Ramprashad Prabhakaran

Transmutation Sciences Materials (TRP)

Introduction

• This research program is aimed at evaluating different types of environment-induced degradation of candidate target materials for applications in transmutation of spent nuclear fuels (SNF).

• Transmutation refers to the elimination of long-lived actinides and fission products from SNF.

Objectives

• Evaluate susceptibility of candidate target materials to stress corrosion cracking (SCC) and localized corrosion (pitting and crevice) in neutral and acidic aqueous environments at ambient and elevated temperatures

• Determine the extent and morphology of cracking in tested materials as functions of experimental and environmental variables including pH, temperature, loading conditions and specimen geometry

• Develop mechanistic …

On-Chip Actuation Of Compliant Bistable Micro-Mechanisms, Michael S. Baker

Theses and Dissertations

Two compliant bistable micro-mechanisms have been developed which can be switched in either direction using on-chip thermal actuation. The energy storage and bistable behavior of the mechanisms are achieved through the elastic deflection of compliant segments. The pseudo-rigid-body model was used for the compliant mechanism design, and for analysis of the large-deflection flexible segments. To achieve on-chip actuation, the mechanism designs were optimized to reduce their required rotation, allow them to be switched using linear-motion thermal actuators. The modeling theory and analysis are presented for several design iterations. Each iteration was successfully fabricated and tested using either the MUMPs or …

Thermal Microactuators For Microelectromechanical Systems (Mems), Rebecca Cragun

Theses and Dissertations

Microactuators are needed to convert energy into mechanical work at the microscale. Thermal microactuators can be used to produce this needed mechanical work. The purpose of this research was to design, fabricate, and test thermal microactuators for use at the microscale in microelectromechanical systems (MEMS). The microactuators developed were tested to determine the magnitude of their deflection and estimate their force. Five groups of thermal microactuators were designed and tested. All of the groups used the geometrically constrained expansion of various segments to produce their deflection. The first group, Thermal Expansion Devices (TEDs), produced a rotational displacement and had deflections …

An Investigation Of Compliant Over-Running Ratchet And Pawl Clutches, Gregory Mark Roach

Theses and Dissertations

This thesis proposes that compliant mechanism theory can be used to design over-running ratchet and pawl clutches with reduced part count, lower assembly and manufacturing time while maintaining functionality. An extension of the theory to the micro regime is also briefly addressed. The results of the research show that the ratchet and pawl type of over-running clutch is a good choice for the use of compliance, and the clutch pawls should be loaded in compression to get the largest amount of output torque. It was found that com-pliant mechanism theory can be used to design ratchet and pawl clutches with …

Learning States And Rules For Time Series Anomaly Detection, Stan Salvador, Philip K. Chan, John Brodie

Electrical Engineering and Computer Science Faculty Publications

In this paper, we investigate machine learning techniques for discovering knowledge that can be used to monitor the operation of devices or systems. Specifically, we study methods for generating models that can detect anomalies in time series data. The normal operation of a device can usually be characterized in different temporal states. To identify these states, we introduce a clustering algorithm called Gecko that can automatically determine a reasonable number of clusters using our proposed "L" method. We then use the RIPPER classification algorithm to describe these states in logical rules. Finally, transitional logic between the states is added to …

Designing, Debugging, And Deploying Configurable Computing Machine-Based Applications Using Reconfigurable Computing Application Frameworks, Anthony Lynn Slade

Theses and Dissertations

Configurable computing machines (CCMs) offer high-performance application acceleration with custom hardware. They are also dynamically reconfigurable and give significant internal visibility. Such features are useful throughout the design, debug, and deploy stages of CCM-based application development. However traditional, monolithic design tools do not offer adequate support for all of these development stages. This thesis describes a specification for a reconfigurable computing application framework (RCAF) which is more suitable for CCM application development. It also describes an implementation of such an RCAF. This RCAF improves the efficiency of application design and debugging. It also establishes an application architecture framework which helps …

Trends. Terrorism, Behavioral Profiling, And Aviation Security, Ibpp Editor

International Bulletin of Political Psychology

This Trends article discusses the quest to improve aviation security by identifying behavioral indicators for terrorism.

A New Approach To Scalable Lindasystems Based On Swarms, Ronaldo Menezes, Robert Tolksdorf

Electrical Engineering and Computer Science Faculty Publications

Natural forming multi-agent systems (aka Swarms) have the ability to grow to enormous sizes without requiring any of the agents to oversee the entire system. The success of these systems comes from the fact that agents are simple and the interaction with the environment and neighboring agents is local in nature. In this paper we look at abstractions in the field of swarms and study their applicability in the context of coordination systems. In particular, we focus on the problematic issue of scalability of Linda systems. The purpose of this work is to look at abstractions yielded from observations of …

Optomechanical Properties Of Stretched Polymer Dispersed Liquid Crystal Films For Scattering Polarizer Applications, Iciro Amimori, Nikolai V. Priezjev, Robert A. Pelcovits, Gregory P. Crawford

Mechanical and Materials Engineering Faculty Publications

A scattering polarizer is created by subjecting a polymer dispersed liquid crystal (PDLC) film to tensile strain. The optomechanical properties of the film are investigated by simultaneously measuring the stress-strain and polarization dependent optical transmission characteristics. The correlation between transmittances of two orthogonal polarizations and the stress-strain curve reveals that the polymer orientation as well as the droplet shape anisotropy influences the liquid crystal alignment within the droplets. A Monte-Carlo simulation based on the Lebwohl-Lasher model is used to explain the subtle influence of polymer orientation on liquid crystal alignment.

An Analysis Of Microbial Contamination In Military Aviation Fuel Systems, Harold W. Graef

Theses and Dissertations

Military aviation fuel systems can be an ideal environment for microorganisms. Microbial growth in hydrocarbon fuel systems arises because of the impracticality of keeping fuel tanks sterile and the inevitable presence of water from condensation. Microbial contaminants in aviation fuel systems are a concern because of their potential to degrade the fuel, accelerate tank corrosion, and threaten flight safety. This research addresses the concern of using more environmentally friendly Fuel System Icing Inhibitors (FSII), which are also biocidal. Are significant levels of microorganisms growing in military aviation fuel systems, and if so, are there any common variables? Forty aviation fuel …

Characterization Of Chlorinated Solvent Degradation In A Constructed Wetland, Nathan D. Clemmer

Theses and Dissertations

Widespread chlorinated ethene contamination of aquifers coupled with high costs of current treatment technologies demand innovative remediation solutions. Wetlands, maintaining anaerobic and aerobic zones promoting the complete degradation of chlorinated ethenes such as Tetrachloroethylene (PCE), could be the answer. This thesis characterized the chlorinated solvent contamination levels in three strata of an upward flow constructed wetland. Analysis of samples was accomplished by purge-and-trap gas chromatography. Water quality parameters, Dissolved Oxygen (DO), Oxidation Reduction Potential (ORP), pH, Conductivity, and Temperature, were also measured in monitoring wells with a water monitoring sonde. After removing data outliers caused by short-circuiting flow, PCE concentrations …

On The Relation Between Two Approaches To Combining Evidence: Ordered Abelian Groups And Uninorms, Ronald R. Yager, Vladik Kreinovich

Departmental Technical Reports (CS)

In this paper, we develop a relationship between two approaches to combining evidence: the Ordered Abelian Group (OAG) approach and the uninorm approach. We show that while there exist uninorms that are not extended OAG's it turns out that for operations which are continuous (in some reasonable sense), these two approaches coincide.

Dirty Pages Of Logarithm Tables, Lifetime Of The Universe, And (Subjective) Probabilities On Finite And Infinite Intervals, Hung T. Nguyen, Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

To design data processing algorithms with the smallest average processing time, we need to know what this "average" stands for. At first glance, it may seem that real-life data are really "chaotic", and no probabilities are possible at all: today, we may apply our software package to elementary particles, tomorrow -- to distances between the stars, etc. However, contrary to this intuitive feeling, there are stable probabilities in real-life data. This fact was first discovered in 1881 by Simon Newcomb who noticed that the first pages of logarithm tables (that contain numbers starting with 1) are more used than the …

Exact Upper Bound On The Mean Of The Product Of Many Random Variables With Known Expectations, Vladik Kreinovich, Scott Ferson, Lev Ginzburg

Departmental Technical Reports (CS)

In practice, in addition to the intervals [xi] of possible values of inputs x1,...,xn, we sometimes also know their means Ei. For such cases, we provide an explicit exact (= best possible) upper bound for the mean of the product x1*...*xn of positive values xi.

Dimension Compactification -- A Possible Explanation For Superclusters And For Empirical Evidence Usually Interpreted As Dark Matter, Vladik Kreinovich

Departmental Technical Reports (CS)

According to modern quantum physics, at the microlevel, the dimension of space-time is at least 11; we only observe 4 dimensions because the others are compactified: the size along each of the other dimensions is much smaller than the macroscale. There is no universally accepted explanation of why exactly 4 dimensions remain at the microscopic level. A natural suggestion is: maybe there is no fundamental reason why exactly 4 dimensions should remain, maybe when we go to even larger scales, some of the 4 dimensions will be compactified as well? In this paper, we explore the consequences of the compactification …