Engineering Commons^™

Observation Of Heat Flow At Transition Temperature In La1–Xcaxmno3 + Delta Oxides, Y. B. Zhang, S. Li, C. Q. Sun, W. Gao, S. X. Dou, P. Hing

Faculty of Engineering - Papers (Archive)

Heat-flow changes of La1–xCaxMnO3 + delta (x=0.25, 0.33, and 0.375) magnetoresistive oxides at their Curie temperatures have been detected using differential scanning calorimetry in the temperature range from 173 to 293 K. However, the transition does not occur in the samples of x=0.125 and 0.5. It was found that the heat flow reflected the transition behavior and the enthalpy change of the transition decreased as the transition temperature increased. These results indicate that the La1–xCaxMnO3 + delta oxides (x=0.25, 0.33, and 0.375) undergo an endothermic phase transition from a low-temperature ferromagnetic metal to a high-temperature paramagnetic insulator. It is assumed …

Development Of A High Power Microwave Plasma Beam Applicator, S. A. Gower

Faculty of Engineering - Papers (Archive)

An efficient plasma beam applicator has been developed that utilizes countercurrent cooling techniques to operate at atmospheric pressure and at microwave powers in excess of 5 kW. The device has been operated continuously for tens of hours and shows no signs of degradation. Argon is used as the discharge gas and once initiated, the plasma is self-sustaining. The beam or jet of plasma is highly collimated with a beam diameter of 3 mm, is in excess of 250 mm in length, and has high heat capacity. It could potentially be used to melt industrial ceramics such as silica and alumina, …

A Hierarchical Classifier For Multispectral Satellite Imagery, Abdesselam Bouzerdoum

Faculty of Engineering and Information Sciences - Papers: Part A

In this article, a hierarchical classifier is proposed for classification of ground-cover types of a satellite image of Kangaroo Island, South Australia. The image contains seven ground-cover types, which are categorized into three groups using principal component analysis. The first group contains clouds only, the second consists of sea and cloud shadow over land, and the third contains land and three types of forest. The sea and shadow over land classes are classified with 99% accuracy using a network of threshold logic units. The land and forest classes are classified by multilayer perceptrons (MLPs) using texture features and intensity values. …

Does The Model Matter For Greg Estimation? A Business Survey Example, Dan Hedlin, Hannah Falvey, Raymond Chambers, Phillip Kokic

Faculty of Engineering and Information Sciences - Papers: Part A

Although asymptotically design-unbiased, GREG estimators may produce bad estimates. The article examines the behaviour of GREG estimators when the underlying models are misspecified. It shows how an efficient GREG estimator was found for a business survey that posed some problems. The work involved data exploration in several steps, combined with analyses of g-weights, residuals and standard regression diagnostics. We discuss two diagnostics for whether a GREG estimate is reasonable or not. A common justification for the use of GREG estimators is that, being asymptotically design unbiased, they are relatively robust to model choice. However, we show that the property of …

Wiener Model Identification And Predictive Control For Dual Composition Control Of A Distillation Column, H H J Bloemen, C T. Chou, T J J Van Den Boom, V Verdult, M Verhaegen, T C. Backx

Faculty of Engineering and Information Sciences - Papers: Part A

The benefits of using the Wiener model based identification and control methodology presented in this paper, compared to linear techniques, are demonstrated for dual composition control of a moderate-high purity distillation column simulation model. An identification experiment design is presented which enables one to identify both the low and high gain directions of the distillation column, properties which are important for control and hard to identify in a conventional identification experiment setup as is demonstrated in the paper. Data from the proposed experiment design is used for indirect closed-loop identification of both a linear and a Wiener model, which shows …

Mat: A Mobile Agent System For Supporting Autonomous Mobile Agents, Wei Li, Minjie Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

Mobile Agent Template (MAT) is a mobile agent system that is under study and development at the Institute of Computing Technology, Chinese Academy of Sciences and sponsored by the University of Wollongong, Australia. MAT is not an alternative to other mobile agent systems, but is an agent system that can provide the autonomy to mobile agents. MAT tries to support new Web applications, such as the mobile computation, by autonomous and mobile agents. Mobile Thread Programming Model (MTPM), Distributed Task Plan (DTP) and Active State Space (ASS) are integral components on which MAT is constructed. Integration of these three components …

Existence Of Positive Solutions Of Some Semilinear Elliptic Equations With Singular Coefficients, Nirmalendu Chaudhuri, Mythily Ramaswamy

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.

Multifibre Spectroscopy Of The Supernova Remnant Candidate Rcw 114, Andrew Walker, William Zealey

Faculty of Engineering and Information Sciences - Papers: Part A

RCW 114 is a filamentary nebula of about 250 arcmin diameter. Based on its large diameter-to-filament-width ratio, the expansion velocity, distance and size of the shell, it has been suggested that RCW 114 is a supernova remnant in its momentum-conserving phase. Confirmation of this identification is important, as the large angular size and extensive optical emission of this object will allow for detailed study to improve our knowledge of supernova remnants and their interaction with the interstellar medium.

We have used the FLAIR instrument on the UK Schmidt Telescope to obtain optical spectra of several filaments in RCW 114. These …

Chandra X-Ray Observations Of The 3c 295 Cluster Core, S W. Allen, G B. Taylor, Paul E J Nulsen, R M. Johnstone, L P. David, S Ettori, A C. Fabian, W R. Forman, C Jones, B Mcnamara

Faculty of Engineering and Information Sciences - Papers: Part A

We examine the properties of the X-ray gas in the central regions of the distant (z=0.46), X-ray luminous cluster of galaxies surrounding the powerful radio source 3C 295, using observations made with the Chandra Observatory. Between radii of 50 and 500 kpc, the cluster gas is approximately isothermal with an emission-weighted temperature, kT∼5 keV. Within the central 50-kpc radius this value drops to kT∼3.7 keV. The spectral and imaging Chandra data indicate the presence of a cooling flow within the central 50-kpc radius of the cluster, with a mass deposition rate of approximately 280 M_{⊙ …}

The Soft X-Ray Background: Evidence For Widespread Disruption Of The Gas Haloes Of Galaxy Groups, K K S Wu, A C. Fabian, Paul E. J Nulsen

Faculty of Engineering and Information Sciences - Papers: Part A

Almost all of the extragalactic X-ray background (XRB) at 0.25 keV can be accounted for by radio-quiet quasars, allowing us to derive an upper limit of 4 keV cm⁻² s⁻¹ sr⁻¹ keV⁻¹ for the remaining background at 0.25 keV. However, the XRB from the gas haloes of groups of galaxies, with gas removal resulting from cooling accounted for, exceeds this upper limit by an order of magnitude if non-gravitational heating is not included. We calculate this using simulations of halo merger trees and realistic gas density profiles, which we require to reproduce the observed gas fractions …

Values Of Minors Of An Infinite Family Of D-Optimal Designs And Their Application To The Growth Problem, C Koukouvinos, M Mitrouli, Jennifer Seberry

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.

Estimation Of Reference Crop Evapotranspiration Using Fuzzy State Models, Lameck O. Odhiambo, R. E. Yoder, D. C. Yoder

Biological Systems Engineering: Papers and Publications

Daily evapotranspiration (ET) rates are needed for irrigation scheduling. Owing to the difficulty of obtaining accurate field measurements, ET rates are commonly estimated from weather parameters. A few empirical or semi–empirical methods have been developed for assessing daily reference crop ET, which is converted to actual crop ET using crop coefficients. The FAO Penman–Monteith method, which is now accepted as the standard method for the computation of daily reference ET, is sophisticated. It requires several input parameters, some of which have no actual measurements but are estimated from measured weather parameters. In this study, we examined the suitability of fuzzy …

Optimization Of Fuzzy Evapotranspiration Model Through Neural Training With Input–Output Examples, Lameck O. Odhiambo, R. E. Yoder, D. C. Yoder, J. W. Hines

Biological Systems Engineering: Papers and Publications

In a previous study, we demonstrated that fuzzy evapotranspiration (ET) models can achieve accurate estimation of daily ET comparable to the FAO Penman–Monteith equation, and showed the advantages of the fuzzy approach over other methods. The estimation accuracy of the fuzzy models, however, depended on the shape of the membership functions and the control rules built by trial–and–error methods. This paper shows how the trial and error drawback is eliminated with the application of a fuzzy–neural system, which combines the advantages of fuzzy logic (FL) and artificial neural networks (ANN). The strategy consisted of fusing the FL and ANN on …

Effects Of Compression Processing Parameters And Antioxidants On Molecular Degradation Of Biodegradable Poly-L-Lactide (Plla), Thomas J. Hannan Jr.

Masters Theses

The purpose of this research was to find a combination of poly (L-lactic acid), also known as poly-L-lactide or (PLLA) and antioxidants that would, together, produce a product whose degradation rate would be advantageous for use in biodegradable medical implants. Intrinsic viscosity tests were conducted on compression molded samples of PLLA that were molded at various processing parameters in order to find optimal parameters. The optimal processing parameters were found to be time 10 minutes, temperature 220°C, and pressure 1000 psi.

The molecular weight of PLLA sample was taken while pressure, time, and temperature were varied. As pressure increased, no …

System Security In An Open Lab Environment, Erik Quist

Masters Theses

This thesis presents a system security process for computer workstations in a university open lab environment, which was developed and implemented for the Lumpkin Hall Computer Labs at Eastern Illinois University (EIU). The system security includes the use of policies and NTFS permissions, registry hacks and script files. These techniques were applied to a mixture of Windows NT 4.0 service pack 6a and Windows 2000 Professional workstations in the Lumpkin Hall Computer Labs. They were then tested for appropriate security setup using a Network Security Checksheet and a survey. The Network Security Checksheet ensured that all of the workstations were …

Arc - An Oai Service Provider For Digital Library Federation, Xiaoming Liu, Kurt Maly, Mohammad Zubair, Michael L. Nelson

Computer Science Faculty Publications

The usefulness of the many on-line journals and scientific digital libraries that exist today is limited by the inability to federate these resources through a unified interface. The Open Archive Initiative (OAI) is one major effort to address technical interoperability among distributed archives. The objective of OAI is to develop a framework to facilitate the discovery of content in distributed archives. In this paper, we describe our experience and lessons learned in building Arc, the first federated searching service based on the OAI protocol. Arc harvests metadata from several OAI compliant archives, normalizes them, and stores them in a search …

Smart Objects And Open Archives, Michael L. Nelson, Kurt Maly

Computer Science Faculty Publications

Within the context of digital libraries (DLs), we are making information objects "first-class citizens". We decouple information objects from the systems used for their storage and retrieval, allowing the technology for both DLs and information content to progress independently. We believe dismantling the stovepipe of "DL-archive-content" is the first step in building richer DL experiences for users and insuring the long-term survivability of digital information. To demonstrate this partitioning between DLs, archives and information content, we introduce "buckets": aggregative, intelligent, object-oriented constructs for publishing in digital libraries. Buckets exist within the "Smart Object, Dumb Archive" (SODA) DL model, which promotes …

Buckets: Smart Objects For Digital Libraries, Michael L. Nelson

Computer Science Faculty Publications

Current discussion of digital libraries (DLs) is often dominated by the merits of the respective storage, search and retrieval functionality of archives, repositories, search engines, search interfaces and database systems. While these technologies are necessary for information management, the information content is more important than the systems used for its storage and retrieval. Digital information should have the same long-term survivability prospects as traditional hardcopy information and should be protected to the extent possible from evolving search engine technologies and vendor vagaries in database management systems. Information content and information retrieval systems should progress on independent paths and make limited …

Finite Element Analysis And Active Control For Nonlinear Flutter Of Composite Panels Under Yawed Supersonic Flow, Khaled Abdel-Motagaly

Mechanical & Aerospace Engineering Theses & Dissertations

A coupled structural-electrical modal finite element formulation for composite panels with integrated piezoelectric sensors and actuators is presented for nonlinear panel flutter suppression under yawed supersonic flow. The first-order shear deformation theory for laminated composite plates, the von Karman nonlinear strain-displacement relations for large deflection response, the linear piezoelectricity constitutive relations, and the first-order piston theory of aerodynamics are employed. Nonlinear equations of motion are derived using the three-node triangular MIN3 plate element. Additional electrical degrees of freedom are introduced to model piezoelectric sensors and actuators. The system equations of motion are transformed and reduced to a set of nonlinear …

Nonlinear Response And Fatigue Estimation Of Surface Panels To White And Non-White Gaussian Random Excitations, Jean-Michel Dhainaut

Mechanical & Aerospace Engineering Theses & Dissertations

In stochastic structural dynamics, the majority of analyses have dealt with linear structures under stationary, Gaussian, and band-limited white noise excitations. Although these simplifying assumptions may be justified, in many processes experimental data have shown quite frequently the non-stationary and non-Gaussian characteristics of the loads. An efficient finite element modal formulation has recently been developed to extend the analysis to nonlinear structural responses. Laminated plate theory and von Karman large displacement relations are used to derive the nonlinear equations of motion for an arbitrarily laminated composite panel subjected to combined acoustic and thermal loads. The nonlinear equations of motion in …

Characterization Of The Biological Activities Of Recombinant Fusion Protein Green Fluorescent Protein/Human Zona Pellucida Protein 3 (Gfp/Hzp3), Zhiyong Lin

Theses and Dissertations in Biomedical Sciences

Despite numerous reports indicating the successful production of bioactive recombinant ZP3, no report has shown the rhZP3 having direct binding activity with human sperm. Recombinant ZP3 generated from our previous study displayed binding activity with human sperm through indirect evidence from hemizona assay (HZA).

This present study focused on the production of recombinant ZP3 with direct binding activity with human sperm. Through the application of a pEGFP expression vector, fusion protein GFP/ZP3 was successfully generated and expressed. The expression of GFP/ZP3 was evidenced by RT-PCR and western blot. The fusion protein was partially purified by Ni-NTA affinity column from cell …

Radiative Interactions In Thermochemical Nonequilibrium Expanding Flows, Srikanth B. Pidugu

Mechanical & Aerospace Engineering Theses & Dissertations

A numerical study is conducted to investigate radiative interactions in flows with thermal and chemical nonequilibrium. The two dimensional spatially elliptic Navier-Stokes equations have been used to numerically investigate different physical processes in the nozzle flow problem. The system of governing equations are solved using explicit, unsplit MacCormack predictor-corrector scheme. The chemistry source term is treated implicitly to alleviate stiffness associated with fast chemical reactions.

Different physical processes considered in this study are investigated in a systematic manner. Finite chemical processes in chemically reacting supersonic nozzle flows are studied. Five hydrogen-air combustion models have been employed to study the influence …

An Integrated Risk Analysis Methodology In A Multidisciplinary Design Environment, Katrina R. Hampton

Engineering Management & Systems Engineering Theses & Dissertations

Design of complex, one-of-a-kind systems, such as space transportation systems, is characterized by high uncertainty and, consequently, high risk. It is necessary to account for these uncertainties in the design process to produce systems that are more reliable. Systems designed by including uncertainties and managing them, as well, are more robust and less prone to poor operations as a result of parameter variability.

The quantification, analysis and mitigation of uncertainties are challenging tasks as many systems lack historical data. In such an environment, risk or uncertainty quantification becomes subjective because input data is based on professional judgment. Additionally, there are …

An Efficient Instruction Cache Scheme For Object-Oriented Languages, Yul Chu, M. R. Ito

Electrical and Computer Engineering Faculty Publications and Presentations

We present an efficient cache scheme, which can considerably reduce instruction cache misses caused by procedure call/returns. This scheme employs N-way banks and XOR mapping functions. The main function of this scheme is to place a group of instructions separated by a call instruction into a bank according to the initial and final bank selection mechanisms. After the initial bank selection mechanism selects a bank on an instruction cache miss, the final bank selection mechanism will determine the final bank for updating a cache line as a correction mechanism. These two mechanisms can guarantee that recent groups of instructions exist …

An Efficient Indirect Branch Predictor, Yul Chu, M. R. Ito

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper, we present a new hybrid branch predictor called the GoStay2, which can effectively reduce indirect misprediction rates. The GoStay2 has two different mechanisms compared to other 2- stage hybrid predictors that use a Branch Target Buffer (BTB) as the first stage predictor: Firstly, to reduce conflict misses in the first stage, a new effective 2-way cache scheme is used instead of a 4-way setassociative. Secondly, to reduce mispredictions caused by an inefficient predict and update rule, a new selection mechanism and update rule are proposed. We have developed a simulation program by using Shade and Spixtools, provided …

Middle-Ear Function With Tympanic-Membrane Perforations. Ii. A Simple Model., Susan E. Voss, John J. Rosowski, Saumil N. Merchant, William T. Peake

Engineering: Faculty Publications

A quantitative model of the human middle ear with a tympanic-membrane ~TM! perforation is developed. The model is constrained by several types of acoustic measurements made on human cadaver ears, which indicate that perforation-induced changes in transmission result primarily from changes in driving pressure across the TM and that perforation-induced change in the structure of the TM and its coupling to the ossicles contributes a substantially smaller component. The model represents the effect of a perforation on the pressure difference across the TM by inclusion of a path for sound coupling through the perforation from the ear canal to the …

Gulfstream Aerospace Aircraft Static Position Utility, Mark Eugene Ray

Legacy ETDs

My research project implements a Java based utility developed for commercial application by Gulfstream Aerospace employees and customers to determine static position data of Gulfstream aircraft. The static position data includes aircraft attitude, nose and main landing gear loads and aircraft ground clearance data.

The previous methods used to obtain this data were a family of spreadsheets. The spreadsheet solution has proven to be awkward and inaccessible for providing the required data. Therefore, Gulfstream Aerospace Management approved the design and implementation of a new aircraft static position utility.

The new utility is identified as the Gulfstream Aircraft Static Position (GASP) …

Assessing The Rate Of Change In The Enterprise Database System Market Over Time Using Dea, Timothy R. Anderson, Keith Hollingsworth, Lane Inman

Engineering and Technology Management Faculty Publications and Presentations

This paper builds upon previous work of using Data Envelopment Analysis (DEA) to measure incremental innovation in technology by applying it to the Online Transaction Processing Market. A variable returns to scale DEA model is utilized to determine an annual rate of change in benchmarks based on data provided by the Transaction Processing Performance Council. This rate of change may then be used to forecast possible future performance trendsetters of the TPC.

Thermodynamic Analysis Of Thermomechanical Coupling In Tangential Couette Flow Of Temperature Dependent Materials, Yasar Demirel

YASAR DEMIREL

Thermodynamic analysis of the thermomechanical coupling in a tangential Couette flow is presented for the Nahme number Na range of 0.5 < Na < 2.5. In the analysis, the temperature and velocity gradients, obtained from the series solutions in the Brinkman number Br, have been used for Newtonian fluids whose viscosity and thermal conductivity are expressed as linear functions of temperature. The entropy generation and the irreversibility distributions due to the thermomechanical coupling are evaluated and displayed graphically across the gap with asymmetric wall temperatures for the Couette flow of ethylene glycol.

Mind At Light Speed: Front Matter, David D. Nolte

David D Nolte