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2010

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A Project-Based Learning Approach To Applied Craft Calculations Within Apprenticeship Education: An Action Research Study, Kevin Furlong Jan 2010

A Project-Based Learning Approach To Applied Craft Calculations Within Apprenticeship Education: An Action Research Study, Kevin Furlong

Theses

Using an Action Research methodology, this study was based in Technologicl University Dublin and conducted with the cooperation of three groups of Phase Six Plumbing apprentices over a ten-month period (three cycles). The main aim of the research project was to establish if a deeper understanding and application of Building Services Applied Calculations could be achieved through the implementation of Project-Based Learning within Apprenticeship Education? Research literature shows that not only in Ireland but also abroad, third level education is experiencing what is described as a ‘maths problem’. With applied calculations and mathematics being a fundamental and essential part of …


Electrochemical Characterisation Of Poly Arylene Vinylenes, Jonathan Moghal, Patrick Lynch, Mary Mcnamara, Hugh Byrne, Gordon Chambers Jan 2010

Electrochemical Characterisation Of Poly Arylene Vinylenes, Jonathan Moghal, Patrick Lynch, Mary Mcnamara, Hugh Byrne, Gordon Chambers

Articles

The electrochemical properties of a newly synthesised set of PPV derivatives were measured by cyclic voltammetry. A new octyloxy substituted PPV derivative was first synthesised (POPV). The structure of the POPV is varied systematically by the replacement of the phenyl units by naphthyl and anthryl units and the effect of these variations on the electrochemical properties is explored. The HOMO–LOMO levels of the polymers were determined from the onset potentials for the p-doping and n-doping scans. From this the electrochemical bandgap for each of the polymers was calculated. The systematic change in the structure of the POPV results in a …


The Extent Of Clientelism In Irish Politics: Evidence From Classifying Dáil Questions On A Local-National Dimension, Sarah Jane Delany, Richard Sinnott, Niall O'Reilly Jan 2010

The Extent Of Clientelism In Irish Politics: Evidence From Classifying Dáil Questions On A Local-National Dimension, Sarah Jane Delany, Richard Sinnott, Niall O'Reilly

Conference papers

The availability of the full text of Irish parliamentary questions offers opportunities for using machine learning techniques to examine the currently much discussed role of elected representatives (TDs) in the Irish parliamentary system. Bluntly, are TDs mainly national legislators or “constituency messenger boys”? This paper presents an initial investigation into the use of automated text classification techniques to categorise parliamentary questions from 1922 up to 2008 as national or local. The approach uses a bag of words representation, standard feature reduction methods and an SVM classifier. Initial results show there is very little evidence in the corpus of parliamentary questions …


Quantitative Modelling Approaches For Ascorbic Acid Degradation And Non-Enzymatic Browning Of Orange Juice During Ultrasound Processing, Vasilis Valdramidis, Patrick J. Cullen, Brijesh Tiwari, Colm O’Donnell Jan 2010

Quantitative Modelling Approaches For Ascorbic Acid Degradation And Non-Enzymatic Browning Of Orange Juice During Ultrasound Processing, Vasilis Valdramidis, Patrick J. Cullen, Brijesh Tiwari, Colm O’Donnell

Articles

The objective of this study was to develop a deterministic modelling approach for non-enzymatic browning (NEB) and ascorbic acid (AA) degradation in orange juice during ultrasound processing. Freshly squeezed orange juice was sonicated using a 1,500 W ultrasonic processor at a constant frequency of 20 kHz and processing variables of amplitude level (24.4 – 61.0 μm), temperature (5 – 30 oC) and time (0 – 10 min). The rate constants of the NEB and AA were estimated by a primary model (zero and first order) while their relationship with respect to the processing factors was tested for a number of …


Growth And Kinetics Of Lactobacillus Plantarum In The Fermentation Of Edible Irish Brown Seaweeds, Shilpi Gupta, Nissreen Abu-Ghannam, Amalia G.M. Scannell Jan 2010

Growth And Kinetics Of Lactobacillus Plantarum In The Fermentation Of Edible Irish Brown Seaweeds, Shilpi Gupta, Nissreen Abu-Ghannam, Amalia G.M. Scannell

Articles

The aim of the present study was to see the applicability of using brown edible seaweeds as a sole source of nutrition for the growth of lactic acid bacteria. Growth kinetics of lactic acid bacteria (LAB; Lactobacillus plantarum) was studied using three species of edible Irish brown seaweeds Himanthalia elongata, Laminaria digitata and Laminaria saccharina. As part of the screening process, growth of the LAB was carried out on raw and heat treated forms of seaweeds. The seaweed species in their raw state could not support the growth of L. plantarum. Heat treatment resulted in almost 4 times increase in …


Modelling The Growth Inhibition Of Common Food Spoilage And Pathogenic Micro-Organisms In Presence Of Solvent Extract From Irish York Cabbage, Shilpi Gupta, Amit Jaiswal, Nissreen Abu-Ghannam Jan 2010

Modelling The Growth Inhibition Of Common Food Spoilage And Pathogenic Micro-Organisms In Presence Of Solvent Extract From Irish York Cabbage, Shilpi Gupta, Amit Jaiswal, Nissreen Abu-Ghannam

Articles

Preservatives are required to maintain the quality, extend shelf life, and ensure safety of fresh and processed food products. Although chemical preservatives form an essential part in food preservation, legislation has restricted their use in different foods. Vegetables in the Brassica family (Cabbage, Broccoli, Brussels sprouts) are a rich source of a number of bioactive compounds such as flavonoids, glucosinolates and their breakdown products which may have antimicrobial, antioxidant and anticancer properties. The present study investigates the antimicrobial activities of solvent extract from Irish York cabbage, Brocolli and Brussels Sprouts on the growth inhibition of common food spoilage (Listeria monocytogenes …


Pk/Pd Modelling Of Comb-Shaped Pegylated Salmon Calcitonin Conjugates Of Differing Molecular Weights, Sinead Ryan, Jesus Maria Frias, David H. Haddleton, David J. Brayden Jan 2010

Pk/Pd Modelling Of Comb-Shaped Pegylated Salmon Calcitonin Conjugates Of Differing Molecular Weights, Sinead Ryan, Jesus Maria Frias, David H. Haddleton, David J. Brayden

Articles

Salmon calcitonin (sCT) was conjugated via cysteine-1 to novel combed-shaped end-functionalised poly(PEG) methyl ether methacrylate) (sCT-P) comb-shaped polymers, to yield conjugates of total molecular weights (MW) inclusive of sCT: 6.5, 9.5, 23 and 40 kDa. The conjugates were characterised by HPLC and their in vitro and in vivo bioactivity was measured by cAMP assay on human T47D cells and following intravenous (i.v.) injection to rats, respectively. Stability against endopeptidases, rat serum and liver homogenates was assessed. There were linear and exponential relationships between conjugate MW with potency and efficacy respectively, however the largest MW conjugate still retained 70% of E …


Postharvest Hardness And Color Evolution Of White Button Mushrooms (Agaricus Bisporus)., Debabandya Mohapatra, Zuberi M. Bira, Joseph Kerry, Jesus Maria Frias, Fernanda A.R. Oliveira Jan 2010

Postharvest Hardness And Color Evolution Of White Button Mushrooms (Agaricus Bisporus)., Debabandya Mohapatra, Zuberi M. Bira, Joseph Kerry, Jesus Maria Frias, Fernanda A.R. Oliveira

Articles

The quality evaluation of mushrooms was studied by storing fresh white button mushroom (Agaricus bisporus) for 6-8 days, at various controlled temperature conditions (3.5 -15°C) and measuring the instrumental textural hardness and color of the mushroom cap for different product batches. A non linear mixed effect weibull model was used to describe mushroom cap texture and color kinetics during storage considering the batch variability into account. Storage temperature was found to play a significant role in controlling texture and colour degradation. On lowering storage temperature i) the extent of the final browning extent in the mushroom after storage …


Cognitive Effort For Multi Agent Systems, Luca Longo Jan 2010

Cognitive Effort For Multi Agent Systems, Luca Longo

Conference papers

Cognitive Effort is a multi-faceted phenomenon that has suffered from an imperfect understanding, an informal use in everyday life and numerous definitions. This paper attempts to clarify the concept, along with some of the main influencing factors, by presenting a possible heuristic formalism intended to be implemented as a computational concept, and therefore be embedded in an artificial agent capable of cognitive effort-based decision support. Its applicability in the domain of Artificial Intelligence and Multi-Agent Systems is discussed. The technical challenge of this contribution is to start an active discussion towards the formalisation of Cognitive Effort and its application in …


Rapid Microwave Synthesis Of Mesoporous Tio2 For Electrochromic Displays, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, Nigel Leyland, David Corr, John Colreavy Jan 2010

Rapid Microwave Synthesis Of Mesoporous Tio2 For Electrochromic Displays, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, Nigel Leyland, David Corr, John Colreavy

Articles

No abstract provided.


Workspace Comparisons Of Setup Configurations For Human-Robot Interaction, Franziska Zacharias, Ian S. Howard, Thomas Hulin, Gerd Hirzinger Jan 2010

Workspace Comparisons Of Setup Configurations For Human-Robot Interaction, Franziska Zacharias, Ian S. Howard, Thomas Hulin, Gerd Hirzinger

School of Engineering, Computing and Mathematics

No abstract provided.


Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy Jan 2010

Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy

Articles

Organic-inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, such as organically modified silanes (Ormosils) have found applications as electronic, optical and protective coatings. Such coatings possess important characteristics such as chemical stability, physical strength and scratch resistance. Further performance improvement is achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through the sol-gel process. However due to the inherent difference in the reactivity of the precursors, the hydrolysis of each precursor must be carried out separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acid or acetyl acetonate prior to hydrolysis, …


A Review Of Bast Fibres And Their Composites. Part 2 - Composites, John Summerscales, Nilmini Dissanayake, Amandeep Virk, Wayne Hall Jan 2010

A Review Of Bast Fibres And Their Composites. Part 2 - Composites, John Summerscales, Nilmini Dissanayake, Amandeep Virk, Wayne Hall

School of Engineering, Computing and Mathematics

Bast fibres are defined as those obtained from the outer cell layers of the stems of various plants. The fibres find use in textile applications and are increasingly being considered as reinforcements for polymer matrix composites as they are perceived to be "sustainable". The fibres are composed primarily of cellulose which potentially has a Young's modulus of similar to 140 GPa (being a value comparable with man-made aramid [Kevlar/Twaron] fibres). The plants which are currently attracting most interest are flax and hemp (in temperate climates) or jute and kenaf (in tropical climates). Part 2 of this review will consider the …


Single Step Morphology-Controlled Synthesis Of Silver Nanoparticles, Vinodkumar Etacheri, Reenamole Georgekutty, Michael Seery, Suresh Pillai Jan 2010

Single Step Morphology-Controlled Synthesis Of Silver Nanoparticles, Vinodkumar Etacheri, Reenamole Georgekutty, Michael Seery, Suresh Pillai

Articles

Silver nanoparticles having different size and plasmon resonances were synthesized through a single step aqueous based method. The current procedure was based on the reduction of silver ions by ascorbic acid in the presence of sodiumborohydride and trisodium citrate. Triangular colloidal nanoparticles having different plasmon resonances (and hence different size and colours) were synthesized by varying only the concentration of ascorbic acid. These nanoparticles were found to be stable without using any surfactants or polymers. This study revealed a strong correlation between particle growth and concentration of constituent chemicals. Crystallinity and phase purity of the silver samples were investigated through …


Context-Dependent Partitioning Of Motor Learning In Bimanual Movements, Ian S. Howard, James N. Ingram, Daniel M. Wolpert Jan 2010

Context-Dependent Partitioning Of Motor Learning In Bimanual Movements, Ian S. Howard, James N. Ingram, Daniel M. Wolpert

School of Engineering, Computing and Mathematics

No abstract provided.


The Role Of Stereotype Threat In The Underrepresentation Of Minority Students In Gifted Education, M. Erin Potter Jan 2010

The Role Of Stereotype Threat In The Underrepresentation Of Minority Students In Gifted Education, M. Erin Potter

Dissertations and Theses @ UNI

Stereotype threat is a social psychological phenomenon that has been demonstrated to negatively affect performance of individuals who are members of non-Asian ethnic minority groups in terms of academic achievement. Although these effects have been documented in adults, very few studies have examined stereotype threat in K-12 students. Further, it is not clear whether stereotype threat could negatively impact students' performance on standardized tests, such as those used for screening for gifted programs. The purpose of this study was to examine whether stereotype threat could be reduced in a sample of Caucasian and African-American middle-school students who were taking a …


Improving The Instruction And Learning Of Topographic Maps Through The Use Of Geospatial Technologies, Troy Dean Schwemm Jan 2010

Improving The Instruction And Learning Of Topographic Maps Through The Use Of Geospatial Technologies, Troy Dean Schwemm

Dissertations and Theses @ UNI

Geographic information technologies (GIT) are spatially based technologies that include geographic information systems (GIS), remote sensing, and global positioning systems (GPS). Though GIT has been used in society for decades, and has grown tremendously in the last 10 years as advancements in technology have become available, its inclusion into the K-12 curriculum has not kept pace. As the educational reform movement places an ever increasing amount of pressure on schools to produce technologically literate, workforce ready graduates, school districts are scrambling to find creative, innovative ways to accomplish this task. Rather than learning passively, GIT allows students to construct their …


Regional Differences In Jurors’ Attitudes And Knowledge, Heather M. Caspers Jan 2010

Regional Differences In Jurors’ Attitudes And Knowledge, Heather M. Caspers

Dissertations and Theses @ UNI

Dynamic social impact theory (DSIT; Latane, 1996) suggests that social influence leads to four phenomena: clustering (regional differences in attitudes), correlation (emergent relationships between attitudes), consolidation (reduction in attitude variance), and continuing diversity (whereby minority opinions persist). These phenomena have been shown in a variety of settings (Harton & Bourgeois, 2004; Harton & Bullock, 2007), but geographic clustering in attitudes about crime have not been examined. These attitudes have the potential to affect a verdict in a trial if a defendant has a change of venue to a different area of the state or the country. Two datasets, the National …


I-Kinetic And Mechanistic Investigations Of Amino Acid Substrates Reactivities With Ferryl Species, Ahmed Ibrahim Youssef Abouelatta Jan 2010

I-Kinetic And Mechanistic Investigations Of Amino Acid Substrates Reactivities With Ferryl Species, Ahmed Ibrahim Youssef Abouelatta

Wayne State University Dissertations

ABSTRACT

I-KINETIC AND MECHANISTIC INVESTIGATIONS OF AMINO ACID SUBSTRATES REACTIVITIES WITH FERRYL SPECIES

II-SYNTHESIS AND CHARACTERIZATION OF DERIVATIVES OF THE BN-TPEN LIGAND AND THEIR METAL COMPLEXES

by

AHMED IBRAHIM YOUSSEF ABOUELATTA

MAY 2011

Advisor: Dr. Jeremy Jacob Kodanko

Major: Chemistry (Organic)

Degree: Doctor of philosophy

The reactivity of tryptophan, methionine, aspartic acid, glutamic acid, histidine and hydrochloride salt of lysine amino acid substrates with the N4Py ferryl species was studied by UV-vis spectroscopy and product characterization. Based on kinetic isotope effect studies and product analysis, an ET-PT mechanism was proposed for the reaction of tryptophan substrate with N4Py ferryl and …


Asymptotic Properties Of Markov Modulated Sequences With Fast And Slow Time Scales, Son Luu Nguyen Jan 2010

Asymptotic Properties Of Markov Modulated Sequences With Fast And Slow Time Scales, Son Luu Nguyen

Wayne State University Dissertations

In this dissertation we investigate asymptotic properties of Markov modulated random processes having two-time scales. The model contains a number of mixing sequences modulated by a switching process that is a discrete-time Markov chain. The motivation of our study stems from applications in manufacturing systems, communication networks, and economic systems, in which regime-switching models are used.

This thesis focuses on asymptotic properties of the Markov modulated processes under suitable scaling. Our main effort focuses on obtaining weak convergence and strong approximation results.


Time-Domain Field Responses Of The Thin, High-Contrast, Finely Layered Structure In Ic Packagings, Adrianus T. De Hoop, Lijun Jiang Jan 2010

Time-Domain Field Responses Of The Thin, High-Contrast, Finely Layered Structure In Ic Packagings, Adrianus T. De Hoop, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The thin, high-contrast, fine layers with dielectric and conductive properties, such as ground planes, are feature structures in IC packagings. Their responses to the pulsed electromagnetic field is important both theoretically and practically. In this paper, a new semi-analytical method is proposed to model the interaction of the layer with an incident electromagnetic field via a boundary condition that expresses the in-plane conduction and contrast electric polarization currents in terms of the exciting incident field by relating the jump in the tangential component of the magnetic field strength across the layer in terms of the (continuous) tangential component of the …


Optimal Control Of Affine Nonlinear Continuous-Time Systems Using An Online Hamilton-Jacobi-Isaacs Formulation, T. Dierks, Sarangapani Jagannathan Jan 2010

Optimal Control Of Affine Nonlinear Continuous-Time Systems Using An Online Hamilton-Jacobi-Isaacs Formulation, T. Dierks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Solving the Hamilton-Jacobi-Isaacs (HJI) equation, commonly used in ℋ∞ optimal control, is often referred to as a two-player differential game where one player tries to minimize the cost function while the other tries to maximize it. in this paper, the HJI equation is formulated online and forward-in-time using a novel single online approximator (SOLA)-Based scheme to achieve optimal regulation and tracking control of affine nonlinear continuous-time systems. the SOLA-Based adaptive approach is designed to learn the infinite horizon HJI equation, the corresponding optimal control input, and the worst-case disturbance. a novel parameter tuning algorithm is derived which not only achieves …


Optimal Control Of Affine Nonlinear Continuous-Time Systems, T. Dierks, Sarangapani Jagannathan Jan 2010

Optimal Control Of Affine Nonlinear Continuous-Time Systems, T. Dierks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the optimal regulation and tracking control of affine nonlinear continuous-time systems with known dynamics is undertaken using a novel single online approximator (SOL)-Based scheme. the SOLA-Based adaptive approach is designed to learn the infinite horizon continuous time Hamilton-Jacobi-Bellman (HJB) equation and its corresponding optimal control input. a novel parameter tuning algorithm is derived which not only ensures the optimal cost (HJB) function and control input are achieved, but also ensures the system states remain bounded during the online learning process. Lyapunov techniques show that all signals are uniformly ultimately bounded (UUB) and the approximated control signal approaches …


Output Feedback Control Of A Quadrotor Uav Using Neural Networks, Travis Dierks, Sarangapani Jagannathan Jan 2010

Output Feedback Control Of A Quadrotor Uav Using Neural Networks, Travis Dierks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new nonlinear controller for a quadrotor unmanned aerial vehicle (UAV) is proposed using neural networks (NNs) and output feedback. the assumption on the availability of UAV dynamics is not always practical, especially in an outdoor environment. Therefore, in this work, an NN is introduced to learn the complete dynamics of the UAV online, including uncertain nonlinear terms like aerodynamic friction and blade flapping. Although a quadrotor UAV is underactuated, a novel NN virtual control input scheme is proposed which allows all six degrees of freedom (DOF) of the UAV to be controlled using only four control …


Mahalanobis Taguchi System (Mts) As A Prognostics Tool For Rolling Element Bearing Failures, Ahmet Soylemezoglu, Sarangapani Jagannathan, Can Saygin Jan 2010

Mahalanobis Taguchi System (Mts) As A Prognostics Tool For Rolling Element Bearing Failures, Ahmet Soylemezoglu, Sarangapani Jagannathan, Can Saygin

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel Mahalanobis-Taguchi system (MTS)-Based fault detection, isolation, and prognostics scheme is presented. the proposed data-driven scheme utilizes the Mahalanobis distance (MD)-Based fault clustering and the progression of MD values over time. MD thresholds derived from the clustering analysis are used for fault detection and isolation. When a fault is detected, the prognostics scheme, which monitors the progression of the MD values, is initiated. Then, using a linear approximation, time to failure is estimated. the performance of the scheme has been validated via experiments performed on rolling element bearings inside the spindle headstock of a microcomputer numerical …


Dynamic System Eigenvalue Extraction Using A Linear Echo State Network For Small-Signal Stability Analysis - A Novel Application, Jiaqi Liang, Jing Dai, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2010

Dynamic System Eigenvalue Extraction Using A Linear Echo State Network For Small-Signal Stability Analysis - A Novel Application, Jiaqi Liang, Jing Dai, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

A large nonlinear dynamic system usually has complex dynamic modes corresponding to the system's eigenvalues. These eigenvalues govern the system's local behavior and thus are critical information for designing system operation and control strategies. Without the availability of the system's analytical model, which is often the case for large nonlinear systems, the system's eigenvalues need to be estimated. a linear echo state network (ESN) based method for extracting observable eigenvalues of a dynamic system together with the participation factors of these eigenvalues in the accessible system states is presented in this paper. a linear ESN is first trained to track …


Wikipedia2onto: Building Concept Ontology Automatically, Experimenting With Web Image Retrieval, Huan Wang, Xing Jiang, Liang-Tien Chia, Ah-Hwee Tan Jan 2010

Wikipedia2onto: Building Concept Ontology Automatically, Experimenting With Web Image Retrieval, Huan Wang, Xing Jiang, Liang-Tien Chia, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Given its effectiveness to better understand data, ontology has been used in various domains including artificial intelligence, biomedical informatics and library science. What we have tried to promote is the use of ontology to better understand media (in particular, images) on the World Wide Web. This paper describes our preliminary attempt to construct a large-scale multi-modality ontology, called AutoMMOnto, for web image classification. Particularly, to enable the automation of text ontology construction, we take advantage of both structural and content features of Wikipedia and formalize real world objects in terms of concepts and relationships. For visual part, we train classifiers …


Accelerated Lattice Boltzmann Method For Colloidal Suspensions Rheology And Interface Morphology, Hassan Farhat Jan 2010

Accelerated Lattice Boltzmann Method For Colloidal Suspensions Rheology And Interface Morphology, Hassan Farhat

Wayne State University Dissertations

ABSTRACT

ACCELERATED LATTICE BOLTZMANN MODEL FOR COLLOIDAL SUSPENSIONS RHEOLOGY AND INTERFACE MORPHOLOGY

by

HASSAN FARHAT

July 2010

Advisor: Dr. Singh Trilochan

Co-Advisor: Dr. Joon Sang Lee

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Colloids are ubiquitous in the food, medical, cosmetic, polymer, water purification and pharmaceutical industries. Colloids thermal, mechanical and storage properties are highly dependent on their interface morphology and their rheological behavior.

Numerical methods provide a cheap and reliable virtual laboratory for the study of colloids. However efficiency is a major concern to address when using numerical methods for practical applications.

This work introduces the main building-blocks for …


Innovative Acoustic Reflection Imaging Techniques And Application To Clinical Breast Tomography, Steve Phillip Schmidt Jan 2010

Innovative Acoustic Reflection Imaging Techniques And Application To Clinical Breast Tomography, Steve Phillip Schmidt

Wayne State University Dissertations

Conventional ultrasound techniques use beam-formed, constant sound speed ray models for fast image reconstruction. However, these techniques are inadequate for the emerging new field of ultrasound tomography (UST). We present a new technique for reconstruction of reflection images from UST data. We have extended the planar Kirchhoff migration method used in geophysics, and combined it with sound speed and attenuation data obtained from the transmission signals to create reflection ultrasound images that are corrected for refractive and attenuative effects.

The resulting techniques were applied to simulated numerical phantom data, physical phantom data and in-vivo breast data obtained with an experimental …


Impedance Spectroscopy Of Batio₃ Cubes Suspended In Lossy Liquids As A Physical Model Of Two-Phase System, Piotr Z. Jasinski, Vladimir Petrovsky, Fatih Dogan Jan 2010

Impedance Spectroscopy Of Batio₃ Cubes Suspended In Lossy Liquids As A Physical Model Of Two-Phase System, Piotr Z. Jasinski, Vladimir Petrovsky, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Impedance spectroscopy techniques were used for analysis of the physical model in a two-phase system toward determining of dielectric constant of dielectric particles suspended in liquids at various solids loading (volume fraction) levels. Model experimental studies were conducted using BaTiO3 as a dielectric material that was prepared as small cubes of uniform size (2×2×1 mm). Barium titanate (BT) cubes having a dielectric constant of 3850 were immersed in liquids of low dielectric constant and moderate electrical conductivity. Measured impedance spectra consisted of two semicircles, which were fitted for (R∥C)(R∥C) equivalent circuit. The parameters obtained from fitting were compared with the …