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2003

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Articles 931 - 960 of 3876

Full-Text Articles in Physical Sciences and Mathematics

Direct Multielemental Analysis Of Solid Samples Using Laser Ablation Inductively Coupled Plasma Mass Spectometry And Pulsed Radio Frequency Glow Discharge Mass Spectrometry, Joseph Miller Aug 2003

Direct Multielemental Analysis Of Solid Samples Using Laser Ablation Inductively Coupled Plasma Mass Spectometry And Pulsed Radio Frequency Glow Discharge Mass Spectrometry, Joseph Miller

Masters Theses & Specialist Projects

Direct solid sampling is an area of analytical research that has generated a large amount of interest in recent years. Two analysis systems offering fast and nondestructive methods of determining the elemental composition of substances, without requiring complicated sample preparation procedures, are laser ablation inductively coupled plasma mass spectroscopy (LA-ICPMS) and radio frequency glow discharge mass spectroscopy (rf-GDMS). A Cetac LSX-200 laser system coupled to a LECO Renaissance ICPMS was utilized to analyze coal and ash samples prepared by incorporation into a lithium borate matrix to form a disk. In addition, a VG 9000 Glow Discharge Mass Spectrometer (GDMS) with …


Analysis Of Soil Lead Levels In An Historic District Of A South Central Kentucky City, Robert Cummins Aug 2003

Analysis Of Soil Lead Levels In An Historic District Of A South Central Kentucky City, Robert Cummins

Masters Theses & Specialist Projects

Lead in soil has been shown to be a significant pathway of lead exposure in children. Several factors including age of housing units, exterior composition, and paint loading may affect the amount of lead present in the soil. The purpose of this study was to analyze soil lead levels on properties located in an historic district and relate those levels to the variables previously mentioned. A total of 30 soil samples were collected from housing units in a nationally recognized historic district. Concentrations of lead in the soil were analyzed using a NITON X-ray Fluorescence Spectrum Analyzer, following EPA Method …


Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis Aug 2003

Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis

Masters Theses

Volatile organic compounds (VOCs) are detected in two groundwater monitoring wells (MW-60 and MW-62S) located along the northern, downgradient property line of the McGill Road Landfill (MRL) in Jackson, Michigan. Potential on-site sources for groundwater impact are two distinct landfill units at the MRL. Leachate chemistry suggested that landfill leachate was not the source of VOCs detected in groundwater. A potential source for VOCs was landfill gas. Sources of landfill gas in the vicinity of the impacted wells included the distinct MRL landfill units as well as the old Jackson County Landfill (JCL), located hydraulically downgradient from the impacted wells. …


Performance Sensitivity And Fairness Of Ecn-Aware 'Modified Tcp', Archan Misra, Teunis Ott Aug 2003

Performance Sensitivity And Fairness Of Ecn-Aware 'Modified Tcp', Archan Misra, Teunis Ott

Research Collection School Of Computing and Information Systems

The paper discusses how Explicit Congestion Notification (ECN) can be used to devise a congestion control mechanism for the Internet, which is more rapidly reactive and allows best-effort flows to rapidly adjust to fluctuations in available capacity. Our ECN-mod protocol involves simple modifications to TCP behavior and leverages more aggressive marking-based router feedback.Simulations show that ECN-mod is better than TCP NewReno even for Web-style intermittent traffic sources, and makes the link utilization significantly less sensitive to the variation in the number of active flows. Simulations also show that, while ECN-mod flows obtain a larger portion of the available capacity than …


Revisiting The Fresnel Coefficients For Uniform Plane Wave Propagation Across A Nonchiral, Reciprocal And Chiral, Nonreciprocal Interface, Monish Ranjan Chatterjee, Sumit Nema Aug 2003

Revisiting The Fresnel Coefficients For Uniform Plane Wave Propagation Across A Nonchiral, Reciprocal And Chiral, Nonreciprocal Interface, Monish Ranjan Chatterjee, Sumit Nema

Electrical and Computer Engineering Faculty Publications

The problem of EM wave propagation in non-reciprocal chiral media has been studied by several investigators. In a recent approach, a dual-transform technique has been developed to study the problem of such propagation under paraxial and slow-envelope variation conditions.

In this paper, we first outline some of the results obtained using the dual transform technique for arbitrary boundary conditions within the left boundary of a semi-infinite, non-reciprocal chiral medium for a uniform plane wave, and a fundamental Gaussian-profiled beam. Next, we explore the problem of a uniform EM wave incident at an oblique angle at an interface between a reciprocal, …


Receptor Activation Regulates Cortical, But Not Vesicular Localization Of Ndp Kinase, Betty C. Gallagher, Kimberly A.P. Mitchell, Gabor Szabo, Angela De S. Otero Aug 2003

Receptor Activation Regulates Cortical, But Not Vesicular Localization Of Ndp Kinase, Betty C. Gallagher, Kimberly A.P. Mitchell, Gabor Szabo, Angela De S. Otero

Faculty Publications and Presentations

We used immunofluorescence techniques to determine the localization of nucleoside diphosphate (NDP) kinase in NIH-3T3 fibroblasts. We found that cytoplasmic NDP kinase can be separated into two populations according to subcellular localization and response to extracellular stimuli. Specifically, within minutes of stimulation of resting fibroblasts with serum, growth factors or bombesin, a portion of NDP kinase becomes associated with membrane ruffles and lamellipodia. Another pool of NDP kinase accumulates independently of stimulation around intracellular vesicles. Transfection of cells with activated Rac mimics, whereas expression of dominant negative Rac inhibits, the effects of extracellular stimulation on the translocation of NDP kinase …


Eigenvalue Dependence On Problem Parameters For Stieltjes Sturm-Liouville Problems, Laurie Elizabeth Battle Aug 2003

Eigenvalue Dependence On Problem Parameters For Stieltjes Sturm-Liouville Problems, Laurie Elizabeth Battle

Doctoral Dissertations

This work examines generalized Stieltjes Sturm-Liouville boundary value problems with particular consideration of self-adjoint problems. Of central importance is determining conditions under which the eigenvalues depend continuously and differentiably on the problem data. These results can be applied to various physical problems, such as constructing beams to maximize the fundamental frequency of vibration, or constructing columns to maximize the height without buckling. These problems involve maximizing the smallest eigenvalues of Sturm-Liouville equations, and the continuous dependence of the eigenvalues on the problem parameters can be used to accomplish this.

We first consider the generalized 2n-dimensional initial value problem dy …


Computational Models For Diusion Of Second Messengers In Visual Transduction, Harihar Khanal Aug 2003

Computational Models For Diusion Of Second Messengers In Visual Transduction, Harihar Khanal

Doctoral Dissertations

The process of phototransduction, whereby light is converted into an electrical response in retinal rod and cone photoreceptors, involves, as a crucial step, the diffusion of cytoplasmic signaling molecules, termed second messengers. A barrier to mathematical and computational modeling is the complex geometry of the rod outer segment which contains about 1000 thin discs. Most current investigations on the subject assume a well stirred bulk aqueous environment thereby avoiding such geometrical complexity. We present theoretical and computational spatio-temporal models for phototransduction in vertebrate rod photoreceptors, which are pointwise in nature and thus take into account the complex geometry of the …


Building A Vision For Our Weir River Estuary: An Inventory Of Open Space And Public Access Around The Weir River Area Of Critical Environmental Concern And Summary Of The Weir River Estuary Visioning Workshop, Chantal Lefebvre Aug 2003

Building A Vision For Our Weir River Estuary: An Inventory Of Open Space And Public Access Around The Weir River Area Of Critical Environmental Concern And Summary Of The Weir River Estuary Visioning Workshop, Chantal Lefebvre

Urban Harbors Institute Publications

The Weir River Estuary Park Open Space and Public Access Inventory is a planning document designed to provide collective information on public open space and water access opportunities around the Weir River Area of Critical Environmental Concern (ACEC). It catalogs what is known about all undeveloped lands and accessways around the estuary and draws from existing reports and plans, interviews with government officials, and comments conveyed during a day-long public visioning workshop in May 2003. The inventory is intended as a support document to augment existing open space plans, master plans, and harbor management plans in Hingham, Hull, and Cohasset …


Spearman Rank Regression, Jason C. Parcon Aug 2003

Spearman Rank Regression, Jason C. Parcon

Dissertations

The main purpose of this dissertation is to obtain an estimate of the slope parameter in a regression model that is robust to outlying values in both the x - and Y-spaces. The least squares method, though known to be optimal for normal errors, can yield estimates with infinitely large MSE's if the error distribution is thick-tailed. Regular rank-based methods like the Wilcoxon method are known to be robust to outlying values in the Y -space, but it is still grossly affected by outlying values in x -space.

This dissertation derives an estimate of the slope from an estimating …


Fractal Images Generated By Newton's Method.", Jennifer Corte Aug 2003

Fractal Images Generated By Newton's Method.", Jennifer Corte

Masters Theses

We investigate the behavior of Newton's Method for finding roots applied to complex-valued functions of complex variables. This re- quires an analysis of iteration of rational functions. The fractal nature of Newton's Method in the complex plane gives us intricate and beautiful images. By investigating select functions we attempt to generalize a pattern of behavior.


Trochoidal Electron Impact Time-Of-Flight Mass Spectrometry Of Chlorodifluoromethane, Wesley Daniel Robertson Aug 2003

Trochoidal Electron Impact Time-Of-Flight Mass Spectrometry Of Chlorodifluoromethane, Wesley Daniel Robertson

Masters Theses

A Time-of-Fight mass spectrometer (TOF-MS) equipped with both a standard electron gun and a trochoidal electron monochromator was constructed and made operational and used to study ionization processes of the molecule Chlorodifluoromethane (CHF2Cl). The appearance energies of both the parent ion (CHF2Cl+) and the most intense fragment ion (CHF2+) were carefully analyzed and it was observed that the energy for formation of the parent ion, (CHF2Cl+) at 12.50 eV, was at a higher energy than the fragment ion, (CHF2+) at 12.25 eV. This phenomenon …


Integrated Visualization Of Diffusion Tensor And Functional Mri, Nathaniel Richard Fout Aug 2003

Integrated Visualization Of Diffusion Tensor And Functional Mri, Nathaniel Richard Fout

Masters Theses

To understand the morphology, structure, and function of the human brain and the underlying relationships therein has long been a goal of mankind. Technologies are constantly emerging and evolving in an effort to realize this goal, with each new development potentially providing another piece of the puzzle. Among those technologies are advanced imaging modalities such as Diffusion Tensor MRI (DT-MRI) [2] and Functional MRI (fMRI) [8], whose purpose is to provide deeper insight into the neural network connecting functional units of the cerebral cortex. More specifically, DT-MRI captures a description of the fibrous structures (such as nerve fibers) in the …


Structural And Stratigraphic Investigations At The Southwest End Of The Tellico-Sevier Syncline, Southeast Tennessee, Milan A. Heath Ii Aug 2003

Structural And Stratigraphic Investigations At The Southwest End Of The Tellico-Sevier Syncline, Southeast Tennessee, Milan A. Heath Ii

Masters Theses

The southern Appalachian Valley and Ridge is composed of a wedge of Cambrian through Pennsylvanian siliciclastic and carbonate rocks, deformed during latest Paleozoic by the collision of Laurentia and Gondwana. This collision caused the southern Appalachian foreland fold-thrust belt to deform as a critically tapered wedge. This study utilized structural and stratigraphic data to examine the mechanical behavior and timing of emplacement of the southwest end of the Tellico-Sevier syncline within this wedge. The study area is located in southeast Tennessee at the southwest end of the Tellico-Sevier syncline, which is in the first Valley and Ridge thrust sheet west …


An Engineering, Economic, And Political Approach To Beach Erosion Mitigation And Harbor Development: A Review Of The Beach Communities Of Camp Ellis, Maine, Wells, Maine, And Cape May, New Jersey, Edmund Cervone Aug 2003

An Engineering, Economic, And Political Approach To Beach Erosion Mitigation And Harbor Development: A Review Of The Beach Communities Of Camp Ellis, Maine, Wells, Maine, And Cape May, New Jersey, Edmund Cervone

Electronic Theses and Dissertations

The history of coastal engineering projects is fraught with problems. In this thesis I examine the federal navigation project at Wells, Maine. In Wells, an incomplete understanding of the coastal setting led to a faulty engineering design responsible for a poorly functioning inlet and harbor and damage to neighboring beaches and wildlife habitat. Project planners and designers did not account for all unforeseen problems that arose. Reviewing the history of Wells Harbor demonstrates how proper attention to the natural setting, economics, and the political environment is essential to a successful project and enables agencies and stakeholders better to address contingencies …


Effects Of Fiberimatiux Interactions On The Interfacial Deformation Micromechanics Of Cellulose-Fiberipolymer Composites, William Tai-Yin Tze Aug 2003

Effects Of Fiberimatiux Interactions On The Interfacial Deformation Micromechanics Of Cellulose-Fiberipolymer Composites, William Tai-Yin Tze

Electronic Theses and Dissertations

The overall objective of this dissertation was to gain an understanding of the relationship between interfacial chemistry and the micromechanics of the cellulose-fiber/polymer composites. Regenerated cellulose (lyocell) fibers were treated with amine-, phenylamine-, phenyl-, and octadecyl-silanes, and also styrene-maleic anhydride copolymer. Inverse gas chromatography was conducted to evaluate the modified surfaces and to examine the adsorption behavior of ethylbenzene, a model compound for polystyrene, onto the fibers. Micro-composites were formed by depositing micro-droplets of polystyrene onto single fibers. The fiber was subjected to a tensile strain, and Raman spectroscopy was employed to determine the point-to-point variation of the strain- and …


Network Security Risk Assessment Modeling Tools For Critical Infrastructure Assessment, George H. Baker, Samuel Redwine, Joseph Blandino Jul 2003

Network Security Risk Assessment Modeling Tools For Critical Infrastructure Assessment, George H. Baker, Samuel Redwine, Joseph Blandino

George H Baker

The James Madison University (JMU) CIPP research team is developing Network Security Risk Assessment Modeling (NSRAM) tools that will enable the assessment of both cyber and physical infrastructure security risks. The effort is driven by the need to predict and compute the probability of adverse effects stemming from system attacks and malfunctions, to understand their consequences, and to improve existing systems to minimize these consequences.

The tools are targeted at systems supporting critical infrastructures varying from individual systems to organization-wide systems, to systems covering entire geographical regions. Early work emphasizes computing systems, but systems sharing the network nature of computing …


Solubility And Freezing Effects Of Fe2+ And Mg2+ In H2so4 Solutions Representative Of Upper Tropospheric And Lower Stratospheric Sulfate Particles, Matthew E. Wise, Sarah D. Brooks, Rebecca M. Garland, Daniel J. Cziczo, Scot T. Martin, Margaret A. Tolbert Jul 2003

Solubility And Freezing Effects Of Fe2+ And Mg2+ In H2so4 Solutions Representative Of Upper Tropospheric And Lower Stratospheric Sulfate Particles, Matthew E. Wise, Sarah D. Brooks, Rebecca M. Garland, Daniel J. Cziczo, Scot T. Martin, Margaret A. Tolbert

CUP Faculty Research

Chemical elements characteristic of earth minerals and meteorites are present within background tropospheric and stratospheric sulfate aerosol particles. However, it is unknown if these elements are present predominantly as solids, including possible sulfates, carbonates, and oxides, or rather as soluble aqueous metal ions or complexes. Further, it is unclear how these impurities could affect particle freezing. To address these questions, we have determined the total equilibrium metal solubility ([Fe2+]T and [Mg2+]T) in 20–90 wt % sulfuric acid solutions over the temperature range 200–300 K. We have measured solubilities using samples of MgSO4 …


Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (May. 01 – July 31, 2003), Yingtao Jiang, Bingmei Fu, Woosoon Yim Jul 2003

Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (May. 01 – July 31, 2003), Yingtao Jiang, Bingmei Fu, Woosoon Yim

Transmutation Sciences Materials (TRP)

The report for Y01 has been prepared and submitted. The final part of our apparatus, the N3Si4 stirrer, was received by the end of May. The assembly of the apparatus has almost been completed. The control plan for our apparatus has been revised. To run FLUENT, a high-end Unix-based Sun workstation has been acquired. Plan has been made to ship our apparatus to LANL.


Deciding The Nature Of The Coarse Equation Through Microscopic Simulations: The Baby-Bathwater Scheme, J Li, Pg Kevrekidis, Cw Gear, Pg Kevrekidis Jul 2003

Deciding The Nature Of The Coarse Equation Through Microscopic Simulations: The Baby-Bathwater Scheme, J Li, Pg Kevrekidis, Cw Gear, Pg Kevrekidis

Panos Kevrekidis

Recent developments in multiscale computation allow the solution of coarse equations for the expected macroscopic behavior of microscopically evolving particles without ever obtaining these coarse equations in closed form. The closure is obtained on demand through appropriately initialized bursts ofmicroscopic simulation. The effective coupling of microscopic simulators with macrosocopic behavior requires certain decisions about the nature of the unavailable coarse equation. Such decisions include (a) the highest spatial derivative active in the coarse equation, (b) whether the equation satisfies certain conservation laws, and (c) whether the coarse dynamics is Hamiltonian. These decisions affect the number and type of boundary conditions …


Isolation And Characterization Of Thermophilic, Calcium-Precipitating Bacteria Form Calcite Deposits At Yucca Mountain, Terry Ann Else, Curtis R. Pantle, Penny S. Amy, Mark P. Buttner, Amy J. Smiecinski Jul 2003

Isolation And Characterization Of Thermophilic, Calcium-Precipitating Bacteria Form Calcite Deposits At Yucca Mountain, Terry Ann Else, Curtis R. Pantle, Penny S. Amy, Mark P. Buttner, Amy J. Smiecinski

Publications (YM)

Calcite deposits, composed of a mixture of calcium carbonate and silicon dioxide, were found in fractures and small cavities within the welded tuff of Yucca Mountain. This research investigation involves determining the presence of thermophilic, calciumprecipitating bacteria within these deposits. The possible existence of thermophilic bacteria may help to resolve the issue of whether these calcite deposits formed from precipitation of dissolved calcium carbonate in rain water transported from the overlying soil environment or as a result of upwelling of geothermally-heated waters transported from below the mountain. Evidence for microbially-influenced calcite precipitation in these deposits is indicated by the presence …


A Multicentered Approach To Integrated Qm/Qm Calculations. Applications To Multiply Hydrogen Bonded Systems, Brian W. Hopkins, Gregory S. Tschumper Jul 2003

A Multicentered Approach To Integrated Qm/Qm Calculations. Applications To Multiply Hydrogen Bonded Systems, Brian W. Hopkins, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

A multicentered integrated QM/QM technique has been developed. By separating high-level calculations in distinct regions of molecules, the multicentered approach supplants a single large high-level calculation with several smaller calculations. Due to the step polynomial scaling of traditional ab initio quantum chemical methods, this separation significantly enhances the computational efficiency of QM/QM methods. The straightforward implementation of this multicentered approach is illustrated with several large poly-alcohols that form hydrogen bonds with water. The largest alcohol-water complex contains 81 atoms. For properly selected model systems, this multicentered approach introduces essentially no error in the dissociation energies of these complexes relative to …


The Emerging Knowledge Management Paradigm: Some Organizational And Technical Issues, Jens G. Pohl Jul 2003

The Emerging Knowledge Management Paradigm: Some Organizational And Technical Issues, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper addresses the expectations, organizational implications, and information processing requirements, of the emerging knowledge management paradigm. A brief discussion of the enablement of the individual through the wide-spread availability of computer and communication facilities, is followed by a description of the structural evolution of organizations, and the architecture of a computer-based knowledge management system. The author discusses two trends that are driven by the treatment of information and knowledge as a commodity: increased concern for the management and exploitation of knowledge within organizations; and, the creation of an organizational environment that facilitates the acquisition, sharing and application of knowledge. …


Pre-Conference Proceedings Of The Focus Symposium On Collaborative Decision-Support Systems, Collaborative Agent Design Research Center Jul 2003

Pre-Conference Proceedings Of The Focus Symposium On Collaborative Decision-Support Systems, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

The papers included in these pre-conference proceedings reflect the increasing focus on the utilization of computers as collaborating, decision-assistance partners in complex and often time-critical problem situations. There are high expectations that intelligent software agents will solve many of our current information system woes, such as lack of interoperability, multiple failure points, vulnerability to intrusion, making the right information available to the right person at the right time, and proposing solutions under time-critical conditions. Software agents do not have magical human-like capabilities. It is not possible to simply develop a piece of software code that is capable of reasoning about …


The Knowledge Level Approach To Intelligent Information System Design, Michael A. Zang, Jens G. Pohl Jul 2003

The Knowledge Level Approach To Intelligent Information System Design, Michael A. Zang, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Traditional approaches to building intelligent information systems employ an ontology to define a representational structure for the data and information of interest within the target domain of the system. At runtime, the ontology provides a constrained template for the creation of the individual objects and relationships that together define the state of the system at a given point in time. The ontology also provides a vocabulary for expressing domain knowledge typically in the form of rules (declarative knowledge) or methods (procedural knowledge). The system utilizes the encoded knowledge, often in conjunction user input, to progress the state of the system …


Boron-Carbide And Boron Rich Rhobohedral Based Transistors And Tunnel Diodes, Peter A. Dowben Jul 2003

Boron-Carbide And Boron Rich Rhobohedral Based Transistors And Tunnel Diodes, Peter A. Dowben

Peter Dowben Publications

The present invention relates to the fabrication of a boron carbide/boron semiconductor devices. The results suggest that with respect to the approximately 2 eV band gap pure boron material, 0.9 eV band gap boron carbide (B5C) acts as a p-type material. Both boron and boron carbide (B5C) thin films were fabricated from single source borane cage molecules using plasma enhanced chemical vapor deposition (PECVD). Epitaxial growth does not appear to be a requirement. We have doped boron carbide grown by plasma enhanced chemical vapor deposition. The source gas close- 1,2-dicarbadecaborane (orthocarborane) was used to grow the …


Using Caching For Browsing Anonymity, Anna M. Shubina, Sean W. Smith Jul 2003

Using Caching For Browsing Anonymity, Anna M. Shubina, Sean W. Smith

Computer Science Technical Reports

Privacy-providing tools, including tools that provide anonymity, are gaining popularity in the modern world. Among the goals of their users is avoiding tracking and profiling. While some businesses are unhappy with the growth of privacy-enhancing technologies, others can use lack of information about their users to avoid unnecessary liability and even possible harassment by parties with contrary business interests, and to gain a competitive market edge. Currently, users interested in anonymous browsing have the choice only between single-hop proxies and the few more complex systems that are available. These still leave the user vulnerable to long-term intersection attacks. In this …


Tegrid: Demonstration Of A Semantic Web Environment, Steven Gollery, Jens G. Pohl Jul 2003

Tegrid: Demonstration Of A Semantic Web Environment, Steven Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Over the past several years there has been an increasing recognition of the shortcomings of message-passing data-processing systems that compute data without understanding, and the vastly superior potential capabilities of information-centric systems that incorporate an internal information model with sufficient context to support a useful level of automatic reasoning.

The key difference between a data-processing and an information-centric environment is the ability to embed in the information-centric software some understanding of the information being processed. The term information-centric refers to the representation of information in the computer, not to the way it is actually stored in a digital machine. This …


Mechanical Stress Effect On Imprint Behavior Of Integrated Ferroelectric Capacitors, Alexei Gruverman, B. J. Rodriguez, A. I. Kingon, R. J. Nemanich, A. K. Tagantsev, J. S. Cross, M. Tsukada Jul 2003

Mechanical Stress Effect On Imprint Behavior Of Integrated Ferroelectric Capacitors, Alexei Gruverman, B. J. Rodriguez, A. I. Kingon, R. J. Nemanich, A. K. Tagantsev, J. S. Cross, M. Tsukada

Alexei Gruverman Publications

Stress-induced changes in the imprint and switching behavior of (111)-oriented Pb(Zr,Ti)O3 (PZT)-based capacitors have been studied using piezoresponse force microscopy. Visualization of polarization distribution and d33-loop measurements in individual 1x1.5-μm2 capacitors before and after stress application, generated by substrate bending, provided direct experimental evidence of stress-induced switching. Mechanical stress caused elastic switching in capacitors with the direction of the resulting polarization determined by the sign of the applied stress. In addition, stress application turned capacitors into a heavily imprinted state characterized by strongly shifted hysteresis loops and almost complete backswitching after application of the poling voltage. …


Secure Computations On Handheld Devices With The Help Of An Untrusted Server, Jianyong Huang, Willy Susilo, Jennifer Seberry Jul 2003

Secure Computations On Handheld Devices With The Help Of An Untrusted Server, Jianyong Huang, Willy Susilo, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

Recently, handheld devices have become one of the most popular computing tools. Although handheld devices are able to perform anything that a PC can do, their lack of computing power makes it next to impossible to perform some heavy calculations. Hence it appears very useful to have a combination of a handheld with a PC, where the PC can perform heavy calculations to assist the handheld. However, we must be assured that the PC will not have learnt anything from the interaction. In this paper, we show two schemes which involve some server-aided computation where the server has not learnt …