Physical Sciences and Mathematics | Open Access Articles

Review Of Flicker Objectives For Lv, Mv And Hv Systems, Detmar Arlt, Herivelto Bronzeado, Rong Cai, Emmanuel De Jaeger, Zia Emin, David Guillot, Mark Halpin, Naoki Kobayashi, Matti Lahtinen, Igor Papic, Francisco Pazos, Sarath Perera, Jeremy Price, Herwig Renner, Xavier Yang, Francisc Zavoda

Associate Professor Sarath Perera

No abstract provided.

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Power Quality: Recommendations For The Application Of As/Nzs 61000.3.6 And As/Nzs 6100.3.7, Victor Gosbell, Sarath Perera, Victor Smith, D Robinson, Graeme Sanders

Associate Professor Sarath Perera

No abstract provided.

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Hydrogen Energy Storage For A Permanent Magnet Wind Turbine Generator Based Autonomous Hybrid Power System, Nishad Mendis, Saad Sayeef, Kashem Muttaqi, Sarath Perera

Associate Professor Sarath Perera

The Performance of a novel hybrid Remote Area Power Supply (RAPS) system consisting of a Permanent Magnet Synchronous Generator (PMSG), fuel cell system, electrolyser and synchronous condenser is investigated in this paper. The fuel cell system is used to provide power during under-generation scenarios whereas the electrolyser absorbs excess power during over-generation conditions. A synchronous condenser is incorporated into the RAPS system to provide better reactive power and inertial support. Individual controllers for each system module have been developed and implemented. A control coordination methodology is established with a view to regulate the active and reactive power balance of the …

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Harmonics And Flicker Levels At A Sub-Transmission Substation: A Measurement Experience, D Robinson, Victor Gosbell, Sarath Perera, N Browne

Associate Professor Sarath Perera

Proactive monitoring of power quality disturbance levels by electricity utilities is vital to allow cost-effective mitigation when disturbances are perceived to be approaching planning levels and also to protect the security of customer installations. Ensuring that disturbance levels are within limits at the HV and EHV points of supply of the network is essential if satisfactory levels downstream are to be maintained. This paper presents discussion on a power quality monitoring campaign performed at the sub-transmission point of supply of a distribution network with the objective of benchmarking background disturbance levels prior to modifications to the substation and to ensure …

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Conditions For The Assessment Of The Harmonic Compliance Of An Installation, Timothy J. Browne, Sarath Perera, Victor J. Gosbell

Associate Professor Sarath Perera

Methods of allocating harmonic emission limits to customer installations have evolved considerably, as evidenced by the development of harmonic guides such as IEEE-519 and IEC/TR 61000-3-6. However, there is only limited consensus on appropriate techniques validating compliance of installations with those limits. Existing techniques are reviewed and related problems are examined. Conditions which acceptable tests of compliance should meet are proposed.

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Harmonic Survey Of An Mv Distribution System, Victor J. Gosbell, Damian Mannix, D A. Robinson, Sarath Perera

Associate Professor Sarath Perera

The harmonic survey of a medium voltage distribution system involves three major aspects: (i) the choice of harmonic monitor, (ii) the choice of monitoring site, (iii) processing and presentation of results. As well as a discussion of the methodology for these aspects, the paper will discuss the harmonic levels measured, the minimum survey requirements for finding useful data and the harmonic parameters of residential, commercial and industrial loads.

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U.S. Drought Monitor, November 27, 2012, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for November 27, 2012 (11/27/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.

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Hygroscopic Growth And Ccn Activity Of Hulis From Different Environments, Thomas B. Kristensen, Heike Wex, Bettina Nekat, Jacob K. Nøjgaard, Dominik Van Pinxteren, Douglas H. Lowenthal, Lynn Mazzoleni, Katrin Dieckmann, Christian Bender Koch, Thomas F. Mentel, Hartmut Herrmann, A. Gannet Hallar

Department of Chemistry Publications

[1] Humic-like substances (HULIS) constitute a significant fraction of aerosol particles in different environments. Studies of the role of HULIS in hygroscopic growth and cloud condensation nuclei (CCN) activity of aerosol particles are scarce, and results differ significantly. In this work the hygroscopic growth and CCN activity of water extracts (WE) and HULIS extracted from particulate matter (PM) collected at a polluted urban site (Copenhagen, Denmark), a rural site (Melpitz, Germany) and the remote site Storm Peak Laboratory (Colorado, USA) were investigated. Measurements of inorganic ions, elemental carbon, organic carbon and water soluble organic carbon (WSOC) within the PM confirmed …

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Lack Of P53 Affects The Expression Of Several Brain Mitochondrial Proteins: Insights From Proteomics Into Important Pathways Regulated By P53, Ada Fiorini, Rukhsana Sultana, Eugenio Barone, Giovanna Cenini, Marzia Perluigi, Cesare Mancuso, Jian Cai, Jon B. Klein, Daret K. St. Clair, D. Allan Butterfield

Chemistry Faculty Publications

The tumor suppressor protein p53 has been described "as the guardian of the genome" for its crucial role in regulating the transcription of numerous genes responsible for cells cycle arrest, senescence, or apoptosis in response to various stress signals. Although p53 promotes longevity by decreasing the risk of cancer through activation of apoptosis or cellular senescence, several findings suggest that an increase of its activity may have deleterious effects leading to selected aspects of the aging phenotype and neurodegenerative diseases. There is the link between p53 and oxidative stress, the latter a crucial factor that contributes to neurodegenerative processes like …

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Using The Taylor Center To Teach Odes, Alexander Gofen

CODEE Journal

This article introduces a powerful ODE solver called the Taylor Center for PCs (http://taylorcenter.org/Gofen/) as a tool for teaching and performing numeric experiments with ODEs. The Taylor Center is an All-in-One GUI-style application for integrating ODEs by applying the modern Taylor Method (Automatic Differentiation). The Taylor Center also offers dynamic graphics (including 3D stereo vision). After a brief review of the features of the Taylor Center, we consider instructive examples of ODEs in various applications and also several particular examples illustrating intricacies of numeric integration. The article therefore continues the thesis of Borrelli and Coleman (CODEE Journal, http://www.codee.org/ref/CJ09-0157) that awareness …

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An Intense Traveling Airglow Front In The Upper Mesosphere–Lower Thermosphere With Characteristics Of A Bore Observed Over Alice Springs, Australia, During A Strong 2 Day Wave Episode, R. L. Walterscheid, J. H. Hecht, L. J. Galinas, Michael P. Hickey Ph.D., I. M. Reid

Publications

The Aerospace Corporation’s Nightglow Imager observed a large step function change in airglow in the form of a traveling front in the OH Meinel (OHM) and O2 atmospheric (O2A) airglow emissions over Alice Springs, Australia, on 2 February 2003. The front exhibited nearly a factor of 2 stepwise increase in the OHM brightness and a stepwise decrease in the O2A brightness. There was significant (~25 K) cooling behind the airglow fronts. The OHM airglow brightness behind the front was among the brightest for Alice Springs that we have measured in 7 years of observations. The event was associated with a …

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Strategies For Visco-Acoustic Waveform Inversion In The Laplace-Fourier Domain, With Application To The Nankai Subduction Zone, Rie Kamei

Electronic Thesis and Dissertation Repository

Waveform inversion is a non-linear and ill-posed inverse problem, with the objective of utilizing the full information content of recorded seismic waveforms. A Laplace-Fourier domain implementation allows a natural `multiscale' approach that mitigates the non-linearity and ill-posedness by inverting low-frequency, early arrival data in the initial stages of inversion. High-frequency components, and late arrivals are incorporated at a later stage. This allows the development of robust inversion strategies capable of handling large wide-angle crustal surveys, leading to reliable, high-resolution velocity and attenuation models of crustal structures. I apply waveform inversion to extract a P-wave velocity model of the active megasplay …

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Data Acquisition From Cemetery Headstones, Cameron Smith Christiansen

Theses and Dissertations

Data extraction from engraved text is discussed rarely, and nothing in the open literature discusses data extraction from cemetery headstones. Headstone images present unique challenges such as engraved or embossed characters (causing inner-character shadows), low contrast with the background, and significant noise due to inconsistent stone texture and weathering. Current systems for extracting text from outdoor environments (billboards, signs, etc.) make assumptions (i.e. clean and/or consistently-textured background and text) that fail when applied to the domain of engraved text. Additionally, the ability to extract the data found on headstones is of great historical value. This thesis describes a novel and …

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A Cause Of Chaos, R. Nillsen

Professor Rodney Nillsen

An abstract dynamical system consists of a collection S of points together with a transformation, or function, f which maps points of S into points of S. The points in S stand for all possible states of the system. The transformation is a “process of change” over one time unit, that changes each state x in S into another state f(x). Then we can interpret the equation f(x)=y as meaning that if the system is in state x, over the next time unit it will change into the state y. Alternatively, x is a “cause” of y, or x is …

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Don't Do What Australia Has Done, R. Nillsen

Professor Rodney Nillsen

The paper describes and analyses the environment in Australian universities since the changes initiated under the Labor government in 1988 by John Dawkins. It looks at the role and interplay of ideas in the changing intellectual culture in universities, in particular the common effect of the ideas of both liberal economics and postmodernism, and the tensions between corporate values and open enquiry. It raises the issues of the extent to which universities should have a distinct set of values from wider society, and the basis upon which universities should exist as distinctive institutions.

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Differentiate And Make Waves, R. Nillsen

Professor Rodney Nillsen

In 1972 Gary Meisters and Wolfgang Schmidt showed that if the Fourier coefficient of a function is zero at the origin, then the function is a sum of three first order differences. They deduced from this that every translation invariant linear form on the space of square integrable functions on the circle group is automatically continuous. Their results were subsequently developed by the author for the case of n-dimensional Euclidean space (Lectures Notes in Mathematics, vol. 1586, Springer-Verlag,1994). The present paper gives an exposition of some of the ideas in this work, with the aim of minimising the technicalities. In …

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An Application Of Elementary Functions To A Resource Allocation Problem, R. Nillsen

Professor Rodney Nillsen

This paper looks at a problem of resource allocation and analyses the changes and their implications when a particular method of resource allocation is changed, by altering the relative importance of two criteria. The situation considered in the paper arose specifically in the West Report on higher education in Australia (1998), where the possibility of altering the relative importance of research and teaching in allocating university funds in Australia was raised. This possibility was the subject of an article in The Australian newspaper by David Phillips, a former Head of the Higher Education Division in the Department of Employment, Education, …

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An Application Of Quadratic Functions To Australian Government Policy On Funding Schools, R. Nillsen

Professor Rodney Nillsen

In the Sydney Morning Herald newspaper of 23rd March 2005 the economics writer Ross Gittins argued that the funding arrangements for private schools in Australia positively encourage parents to move their children from the state system to the private system. The Federal minister, Dr Brendan Nelson, responded by saying that the policy of subsidising pupils who go to a private school results in taxpayer savings of $4 billion. However, the minister's response did not address the extent to which more funds could possibly be saved by having a different subsidy from the one currently offered by the government. Now, there …

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Function Spaces And Multiplier Operators, R. Nillsen, S. Okada

Professor Rodney Nillsen

Let G denote a locally compact Hausdorff abelian group. Then a bounded linear operator T from L^2(G) into L^2(G) is a bounded multiplier operator if, under the Fourier transform on L^2(G ), for each function f in L^2(G), T(f) changes into a bounded function U times the Fourier transform of f. Then U is called the multiplier of T. An unbounded multiplier operator has a similar definition, but its domain is a dense subspace of L^2(G) and the multiplier function need not be bounded. For example, differentiation on the first order Sobolev subspace of L^2(R) is an unbounded multiplier operator …

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Sharp Results Concerning The Expression Of Functions As Sums Of Finite Differences, R. Nillsen, S. Okada

Professor Rodney Nillsen

A square integrable function on the real line can be written as a finite sum of differences of order s if and only if the Fourier transform of the function vanishes at the origin at a rate comparable with |x|^{-s}. This enables us to see that the space of all such functions becomes a Hilbert space D^s(R) and that this space is the range of the derivative of order s on the Sobolev space of order s. It was proved by the author (Journal of Functional Analysis 110 (1992), 73-95) that each function in D^s(R) is a sum of 2s+1 …

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Normal Numbers Without Measure Theory, R. Nillsen

Professor Rodney Nillsen

Any number can be expanded to the base 10, leading to a sequence of digits between 0 and 9 corresponding to the number. Also, any number can be expanded to the base 2, leading to a sequence of digits, each one being either 0 or 1, corresponding to the number. It is result due to Émile Borel in 1904 that “almost all” numbers have the property that, when expanded to the base 2, each of the digits 0 and 1 appears with an asymptotic frequency of 1/2. That is, if we regard the sequence of digits in the expansion to …

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Can The Love Of Learning Be Taught?, R. Nillsen

Professor Rodney Nillsen

This paper is an expanded version of a talk given at a Generic Skills Workshop at the University of Wollongong, and was originally intended for academic staff from any discipline and general staff with an interest in teaching. The issues considered in the paper include the capacity of all to learn, the distinction between learning as understanding and learning as information, the interaction between the communication and the content of ideas, the tension between perception and content in communication between persons, and the human functions of a love of learning. In teaching, the creation of a fear-free environment is emphasised, …

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Irrational Rotations Motivate Measurable Sets, R. Nillsen

Professor Rodney Nillsen

In 1914 Constantin Carathéodory gave his definition of a measurable set, a definition that is crucial in the general theory of integration. This is because a “primitive” notion of area or measure, on a smaller family of sets, can be extended to the larger family of measurable sets, and it is this larger family that has the necessary properties for a natural and complete theory of integration. This more general theory of integration is of enormous practical importance, for it leads to quite broad conditions under which basic operations on integrals are valid. However, Carathéodory’s definition itself remains mysterious, and …

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The Character Of Free Topological Groups I, Peter R. Nickolas, Mikhail Tkachenko

Associate Professor Peter Nickolas

A systematic analysis is made of the character of the free and free abelian topological groups on uniform spaces and on topological spaces. In the case of the free abelian topological group on a uniform space, expressions are given for the character in terms of simple cardinal invariants of the family of uniformly continuous pseudometrics of the given uniform space and of the uniformity itself. From these results, others follow on the basis of various topological assumptions. Amongst these: (i) if X is a compact Hausdorff space, then the character of the free abelian topological group on X lies between …

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Automatic Detection Of Microcalcifications In Mammorgams Using A Fuzzy Classifier, Fazel Naghdy, Golshah Naghdy, Agustinus Drijarkara

Associate Professor Golshah Naghdy

No abstract provided.

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Cervical Cancer Classification Using Gabor Filters, - Rahmadwati, Golshah Naghdy, Montserrat Ros, Catherine Todd, Eviana Norahmawati

Associate Professor Golshah Naghdy

No abstract provided.

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Signature-Based Document Retrieval, A. Chalechale, G. Naghdy, Alfred Mertins

Associate Professor Golshah Naghdy

This paper presents a new approach for document image decomposition and retrieval based on connected component analysis and geometric properties of the labeled regions. The database contains document images with Arabic/Persian text combined with English text, headlines, ruling lines, trademark and signature. In particular, Arabic/Persian signature extraction is investigated using special characteristics of the signature that is fairly different from English signatures. A set of efficient, invariant and compact features is extracted for validation purposes using angular-radial partitioning of the signature region. Experimental results show the robustness of the proposed method.

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Edge Image Description Using Angular Radial Partitioning, A. Chalechale, Alfred Mertins, G. Naghdy

Associate Professor Golshah Naghdy

The authors present a novel approach for image representation based on geometric distribution of edge pixels. Object segmentation is not needed, therefore the input image may consist of several complex objects. For an efficient description of an arbitrary edge image, the edge map is divided into M/spl times/N angular radial partitions and local features are extracted for these partitions. The entire image is then described as a set of spatially distributed invariant feature descriptors using the magnitude of the Fourier transform. The approach is scale- and rotation-invariant and tolerates small translations and erosions. The extracted features are characterised by their …

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Objective Functional Capacity Assessment Using Inertial Sensor, David Stirling, Fazel Naghdy, Golshah Naghdy, M. Field, R. Arunglabi, D. Kilpatrick

Associate Professor Golshah Naghdy

Functional capacity assessment is carried out to measure the functional limitations of a subject. While the clinical assessment can be validated against various standards, quantifying the assessment and achieving an objective, repeatable, and reliable score in the clinical assessment is a challenge. Current methods are subjective. The Progressive Iso inertial Lifting Evaluation (PILE) is a lifting test developed for functional capacity assessment. The primary aim of this study is to improve reliability and repeatability of PILE through objective measurement of patient's performance. This is achieved by recording and analysing the movement of a patient by a motion capture system based …

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Chain-Based Extraction Of Line Segments To Describe Images, A. Chalechale, G. Naghdy, Prashan Premaratne, H. Moghaddasi

Associate Professor Golshah Naghdy

This work presents a novel fast method for line segment extraction, based on a chain code representation of edge maps. It has a parallel nature and can be employed on parallel machines. In the first phase it breaks the macro chains into several micro chains after applying shifting, smoothing and differentiating. The micro chains are then approximated by straight line segments. In the second phase, based on the length and the error criteria, the line segments are grouped into much longer lines. The experimental results show a significant improvement in the number of line segments extracted while their accumulative length …

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Full-Text Articles in Physical Sciences and Mathematics

Review Of Flicker Objectives For Lv, Mv And Hv Systems, Detmar Arlt, Herivelto Bronzeado, Rong Cai, Emmanuel De Jaeger, Zia Emin, David Guillot, Mark Halpin, Naoki Kobayashi, Matti Lahtinen, Igor Papic, Francisco Pazos, Sarath Perera, Jeremy Price, Herwig Renner, Xavier Yang, Francisc Zavoda

Associate Professor Sarath Perera

Power Quality: Recommendations For The Application Of As/Nzs 61000.3.6 And As/Nzs 6100.3.7, Victor Gosbell, Sarath Perera, Victor Smith, D Robinson, Graeme Sanders

Associate Professor Sarath Perera

Hydrogen Energy Storage For A Permanent Magnet Wind Turbine Generator Based Autonomous Hybrid Power System, Nishad Mendis, Saad Sayeef, Kashem Muttaqi, Sarath Perera

Associate Professor Sarath Perera

Harmonics And Flicker Levels At A Sub-Transmission Substation: A Measurement Experience, D Robinson, Victor Gosbell, Sarath Perera, N Browne

Associate Professor Sarath Perera

Conditions For The Assessment Of The Harmonic Compliance Of An Installation, Timothy J. Browne, Sarath Perera, Victor J. Gosbell

Associate Professor Sarath Perera

Harmonic Survey Of An Mv Distribution System, Victor J. Gosbell, Damian Mannix, D A. Robinson, Sarath Perera

Associate Professor Sarath Perera

U.S. Drought Monitor, November 27, 2012, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Hygroscopic Growth And Ccn Activity Of Hulis From Different Environments, Thomas B. Kristensen, Heike Wex, Bettina Nekat, Jacob K. Nøjgaard, Dominik Van Pinxteren, Douglas H. Lowenthal, Lynn Mazzoleni, Katrin Dieckmann, Christian Bender Koch, Thomas F. Mentel, Hartmut Herrmann, A. Gannet Hallar

Department of Chemistry Publications

Chemistry Faculty Publications

Using The Taylor Center To Teach Odes, Alexander Gofen

CODEE Journal

An Intense Traveling Airglow Front In The Upper Mesosphere–Lower Thermosphere With Characteristics Of A Bore Observed Over Alice Springs, Australia, During A Strong 2 Day Wave Episode, R. L. Walterscheid, J. H. Hecht, L. J. Galinas, Michael P. Hickey Ph.D., I. M. Reid

Publications

Strategies For Visco-Acoustic Waveform Inversion In The Laplace-Fourier Domain, With Application To The Nankai Subduction Zone, Rie Kamei

Electronic Thesis and Dissertation Repository

Data Acquisition From Cemetery Headstones, Cameron Smith Christiansen

Theses and Dissertations

A Cause Of Chaos, R. Nillsen

Professor Rodney Nillsen

Don't Do What Australia Has Done, R. Nillsen

Professor Rodney Nillsen

Differentiate And Make Waves, R. Nillsen

Professor Rodney Nillsen

An Application Of Elementary Functions To A Resource Allocation Problem, R. Nillsen

Professor Rodney Nillsen

An Application Of Quadratic Functions To Australian Government Policy On Funding Schools, R. Nillsen

Professor Rodney Nillsen

Function Spaces And Multiplier Operators, R. Nillsen, S. Okada

Professor Rodney Nillsen

Sharp Results Concerning The Expression Of Functions As Sums Of Finite Differences, R. Nillsen, S. Okada

Professor Rodney Nillsen

Normal Numbers Without Measure Theory, R. Nillsen

Professor Rodney Nillsen

Can The Love Of Learning Be Taught?, R. Nillsen

Professor Rodney Nillsen

Irrational Rotations Motivate Measurable Sets, R. Nillsen

Professor Rodney Nillsen

The Character Of Free Topological Groups I, Peter R. Nickolas, Mikhail Tkachenko

Associate Professor Peter Nickolas

Automatic Detection Of Microcalcifications In Mammorgams Using A Fuzzy Classifier, Fazel Naghdy, Golshah Naghdy, Agustinus Drijarkara

Associate Professor Golshah Naghdy

Cervical Cancer Classification Using Gabor Filters, - Rahmadwati, Golshah Naghdy, Montserrat Ros, Catherine Todd, Eviana Norahmawati

Associate Professor Golshah Naghdy

Signature-Based Document Retrieval, A. Chalechale, G. Naghdy, Alfred Mertins

Associate Professor Golshah Naghdy

Edge Image Description Using Angular Radial Partitioning, A. Chalechale, Alfred Mertins, G. Naghdy

Associate Professor Golshah Naghdy

Objective Functional Capacity Assessment Using Inertial Sensor, David Stirling, Fazel Naghdy, Golshah Naghdy, M. Field, R. Arunglabi, D. Kilpatrick

Associate Professor Golshah Naghdy

Chain-Based Extraction Of Line Segments To Describe Images, A. Chalechale, G. Naghdy, Prashan Premaratne, H. Moghaddasi

Associate Professor Golshah Naghdy