Physical Sciences and Mathematics Commons^™

Online Bayesian Tree-Structured Transformation Of Hmms With Optimal Model Selection For Speaker Adaptation, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents a new recursive Bayesian learning approach for transformation parameter estimation in speaker adaptation. Our goal is to incrementally transform or adapt a set of hidden Markov model (HMM) parameters for a new speaker and gain large performance improvement from a small amount of adaptation data. By constructing a clustering tree of HMM Gaussian mixture components, the linear regression (LR) or affine transformation parameters for HMM Gaussian mixture components are dynamically searched. An online Bayesian learning technique is proposed for recursive maximum a posteriori (MAP) estimation of LR and affine transformation parameters. This technique has the advantages of …

Dirt Road Corrugations, Temple H. Fay, Keith A. Hardie, Stephan V. Joubert

Faculty Publications

WE CONSIDER FACTORS INFLUENCING the build-up of corrugations on dirt roads and the reactions of vehicles to them. We suggest that corrugations are (at least in part) a consequence of a natural tangential oscillation of the tread surface of the car lure that occurs when the vehicle is being driven or braked. Secondly, we suggest that the unpleasant vibration experienced by a vehicle passing over a corrugated road is the result of a beat produced by the difference of the frequency of oscillation of its own tyres and the frequency of the stimulation received by the vehicle due to passage …

The Blazhko Effect Of The Rr Lyrae Star Dr Andromedae, Kevin M. Lee, Edward G. Schmidt

Edward Schmidt Publications

We have obtained 551 new V and R observations of the RR Lyrae star DR Andromedae. Our data set is consistent with a primary period of 0.563118 days; however, the light curve of DR And cannot be well described by a single period. We conclude that DR And demonstrates the Blazhko effect with a Blazhko period of approximately 57.5 days.

Progressive Transmission Of Spatial Data Over The Www: Challenges, James Carswell

Conference papers

Progressive transmission of raster images over the WWW has been successfully applied to provide users with coarser versions of the data before downloading a complete image. In the vector domain, progressive transmission remains a challenging topic. Increasing the level of detail of a vector dataset is a complex process that does not simply imply adding pixels to it. In this paper we present a survey of existing models for progressive transmission of spatial data and discuss open problems and challenges related to the progressive transmission of geographic maps in vector format. Finally, we propose a model based on a client-server …

Analysis And Numerical Solution Of An Integral Equation Method For Electromagnetic Scattering From A Cavity In A Ground Plane, Eric T. Howe

Theses and Dissertations

In this research the electromagnetic scattering of a plane wave from a two-dimensional cavity embedded in an infinite, perfectly conducting ground plane is investigated. The plane wave is assumed to be under transverse electric (TE) polarization with respect to the x-axis. The cavity may be empty or filled with an arbitrary homogeneous, lossy material. A coupled set of scalar integral equations that govern the electromagnetic scattering is implemented. An approximate solution to the scalar integral equations is found via a Method of Moments (MoM) algorithm. The algorithm is implemented in a computer code, and approximations to the total magnetic field …

Composition Operators And A Pull-Back Measure Formula, Valentin Matache

Mathematics Faculty Publications

A pull-back measure formula obtained in some particular cases by E. A. Nordgren and this author is generalized in the framework of boundary measures for zero-free Nevanlinna class fuctions on the unit polydisk. The formula is used to characterize the zero-free Nevanlinna class functions which are solutions of Schröder's equation induced by a polydisk automorphism ϕ (i.e. to determine the zero-free functionsf belonging to the Nevanlinna class which are solutions of the functional equationf ° π=λf, for some constant λ), thus generalizing earlier results obtained by R. Mortini and this author.

Mev Magnetosheath Ions Energized At The Bow Shock, S. Chang, J. D. Scudder, K. Kudela, Harlan E. Spence, J. F. Fennell, R. P. Lepping, R. P. Lin, C. T. Russell

Physics & Astronomy

A causal relationship between midlatitude magnetosheath energetic ions and bow shock magnetic geometry was previously established for ion energy up to 200 keV e−1 for the May 4, 1998, storm event. This study demonstrates that magnetosheath ions with energies above 200 keV up to 1 MeV simply extend the ion spectrum to form a power law tail. Results of cross-correlation analysis suggest that these ions also come directly from the quasi-parallel bow shock, not the magnetosphere. This is confirmed by a comparison of energetic ion fluxes simultaneously measured in the magnetosheath and at the quasi-parallel bow shock when both regions …

Dynamical Relativistic Effects In Photoionization: Spin-Orbit-Resolved Angular Distributions Of Xenon 4d Photoelectrons Near The Cooper Minimum, H. Wang, G. Snell, Oliver Hemmers, M. M. Sant'anna, I. A. Sellin, N. Berrah, Dennis W. Lindle, P. C. Deshmukh, N. Haque, S. T. Manson

Environmental Studies Faculty Publications

Two decades ago, it was predicted [Y. S. Kim et al., Phys. Rev. Lett. 46, 1326 (1981)] that relativistic effects should alter the dynamics of the photoionization process in the vicinity of Cooper minima. The present experimental and theoretical study of the angular distributions of Xe 4d_3/2 and 4d_5/2 photoelectrons demonstrates this effect for the first time. The results clearly imply that relativistic effects are likely to be important for intermediate- Z atoms at most energies.

Development And Construction Of A White Light Profiler For Industrial Applications, Martin Somers

Masters

With the ever decreasing tolerances in modern manufacturing processes it has become more important to define surface topography measurements quickly and accurately. Though contact methods, using the stylus probe, have been used for a long time more optical techniques are being brought into the market place. The advantages in using optical methods is obvious; no contact with the surface eliminates damage due to a probing tip and also the surface may be scanned in a matter of seconds. Optical techniques also have the advantage that a full field of view may be acquired, unlike point measurement where the surface must …

Development Of A Large-Scale Laboratory Facility For Sediment Transport Research, David G. Hamilton, Bruce A. Ebersole, Ernest R. Smith, Ping Wang

Geology Faculty Publications

No abstract provided.

Improving Cluster Utilization Through Set Based Allocation Policies, Quinn O. Snell, Julio C. Facelli, Brian D. Haymore, David B. Jackson

Faculty Publications

While clusters have already proven themselves in the world of high performance computing, some clusters are beginning to exhibit resource inefficiencies due to increasing hardware diversity. Much of the success of clusters lies in the use of commodity components built to meet various hardware standards. These standards have allowed a great level of hardware backwards compatibility that is now resulting in a condition referred to as hardware 'drift' or heterogeneity. The hardware heterogeneity introduces problems when diverse compute nodes are allocated to a parallel job, as most parallel jobs are not self-balancing. This paper presents a new method that allows …

Measurement Of The W Boson Mass With The Collider Detector At Fermilab, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We present a measurement of the W boson mass using data collected with the CDF detector during the 1994–1995 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 30115 W→eν events recorded in an integrated luminosity of 84 pb^-1 gives a mass M_w=80.473±0.065(stat) ±0.092(syst) GeVc². A fit to the transverse mass spectrum of a sample of 14740 W→μν events from 80 pb^-1 gives a mass M_w=80.465±0.100(stat) ±0.103(syst) GeV/c². The dominant contributions to the systematic uncertainties are the …

Thermal Activation Between Landau Levels In The Organic Superconductor Β″-(Bedt-Ttf)2sf5ch2cf2so3, Gary L. Gard, M. S. Nam, A. Ardavan, J. A. Symington, J. Singleton, N. Harrison, C. H. Mielke, J. A. Schlueter, Rolf Walter Winter

Chemistry Faculty Publications and Presentations

We show that Shubnikov–de Haas oscillations in the interlayer resistivity of the organic superconductor β″-(BEDT-TTF)₂SF₅CH₂CF₂SO₃ become very pronounced in magnetic fields ~60T. The conductivity minima exhibit thermally activated behavior that can be explained simply by the presence of a Landau gap, with the quasi-one-dimensional Fermi surface sheets contributing negligibly to the conductivity. This observation, together with complete suppression of chemical potential oscillations, is consistent with an incommensurate nesting instability of the quasi-one-dimensional sheets.

Evaluation Of Comparative Watercraft Personal Property Taxation In Middle Peninsula Localities, Thomas J. Murray

Reports

The Marine Business and Coastal Development Program, Sea Grant Marine Advisory Services at the Virginia Institute of Marine Science, (VIMS) has completed a characterization of the personal property taxing methodologies currently used by Middle Peninsula localities. In conjunction with the Middle Peninsula Planning District Commission's (MPPDC) Coastal Technical Assistance Program, the investigation details the following information:

1. Documentation of the watercraft taxing methodology currently used in the MPPDC counties of Gloucester, Mathews, Middlesex, King and Queen, King William, and Essex County.

2. A comparison of resulting taxes assessed by each of the MPPDC localities on some "standardized" boats.

3. A …

Nature Of Charge Carriers In Disordered Molecular Solids: Are Polarons Compatible With Observations?, Paul Ernest Parris, Vasudev M. Kenkre, David H. Dunlap

Physics Faculty Research & Creative Works

Polaronic theories for charge transport in disordered organic solids, particularly molecularly doped polymers, have been plagued by issues of internal consistency related to the magnitude of physical parameters. We present a natural resolution of the problem by showing that, in the presence of correlated disorder, polaronic carriers with binding energies Δ ~ 50 - 500 meV and transfer integrals J ~ 1 - 20 meV are completely consistent with the magnitudes of field and temperature dependent mobilities observed.

Carbon Dynamics In Peat Bogs: Insights From Substrate Macromolecular Chemistry, Kuder Tomasz, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The macromolecular compositions of subfossil plants from boreal Sphagnum bogs and restiad bogs (New Zealand) have been studied by pyrolysis-gas chromatography/mass spectrometry to evaluate the extent of degradation in the anoxic zone (catotelm) of a peat bog. Degradation of vascular plant polysaccharides was apparent only into the upper catotelm. Sphagnum was degraded more slowly than vascular plants, but no cessation of degradation was observed. The inferred rate of degradation varied depending on type of plant, extent of aerobic, precatotelmic degradation, and mode of litter deposition (rooting versus at the surface). Environmental forcing on anaerobic carbon dynamics would potentially be largest …

C-Band Sar Backscatter Characteristics Of Arctic Sea And Land Ice During Winter, Konrad Steffen, John Heinrichs

Geosciences Faculty Publications

Synthetic Aperture Radar (SAR) data has become an important tool for studies of polar regions, due to high spatial resolution even during the polar night and under cloudy skies. We have studied the temporal variation of sea and land ice backscatter of twenty-four SAR images from the European Remote Sensing satellite (ERS-1) covering an area in Lady Ann Strait and Jones Sound, Nunavut, from January to March 1992. The presence of fast ice in Jones Sound and glaciers and ice caps on the surrounding islands provides an ideal setting for temporal backscatter studies of ice surfaces. Sample regions for eight …

Exploiting Image Indexing Techniques In Dct Domain, Chong-Wah Ngo, Ting-Chuen Pong, Ronald T. Chin

Research Collection School Of Computing and Information Systems

This paper is concerned with the indexing and retrieval of images based on features extracted directly from the JPEG discrete cosine transform (DCT) domain. We examine possible ways of manipulating DCT coefficients by standard image analysis approaches to describe image shape, texture, and color. Through the Mandala transformation, our approach groups a subset of DCT coefficients to form ten blocks. Each block represents a particular frequency content of the original image. Two blocks are used to model rough object shape; nine blocks to describe subband properties; and one block to compute color distribution. As a result, the amount of data …

Vide: A Visual Data Extraction Environment For The Web, Yi Li, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the rapid growth of information on the Web, a means to combat information overload is critical. In this paper, we present ViDE (Visual Data Extraction), an interactive web data extraction environment that supports efficient hierarchical data wrapping of multiple web pages. ViDE has two unique features that differentiate it from other extraction mechanisms. First, data extraction rules can be easily specified in a graphical user interface that is seamlessly integrated with a web browser. Second, ViDE introduces the concept of grouping which unites the extraction rules for a set of documents with the navigational patterns that exist among them. …

Tunable Local Polariton Modes In Semiconductors, Michael G. Foygel, Alexey Yamilov, Lev I. Deych, Alexander A. Lisyansky

Physics Faculty Research & Creative Works

We study the local states within the polariton band gap that arise due to deep defect centers with strong electron-phonon coupling. Electron transitions involving deep levels may result in alteration of local elastic constants. In this case, substantial reversible transformations of the impurity polariton density of states occur, which include the appearance/disappearance of the polariton impurity band, and its shift and/or the modification of its shape. These changes can be induced by thermo- and photoexcitation of the localized electron states or by trapping of injected charge carriers. We develop a simple model, which is applied to the O_p center …

A Transaction Model To Improve Data Availability In Mobile Computing, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

We incorporate a prewrite operation before a write operation in a mobile transaction to improve data availability. A prewrite operation does not update the state of a data object but only makes visible the future value that the data object will have after the final commit of the transaction. Once a transaction reads all the values and declares all the prewrites, it can pre-commit at mobile host (MH) (computer connected to unreliable mobile communication network). The remaining transaction's execution (writes on database) is shifted to the mobile service station (MSS) (computer connected to the reliable fixed network). Writes on database …

Comment On “Photodetachment In Combined Static And Dynamic Electric Fields”`, Ilya I. Fabrikant, M.V. Frolov, N. L. Manakov, Anthony F. Starace

Anthony F. Starace Publications

The theoretical analysis of C. Rangan and A. R. P. Rau [Phys. Rev. A 61, 033405 (2000)] on the process of photodetachment of H^- in a strong static electric field, which calls into question the predictions of B. Gao and A. F. Starace [Phys. Rev. A 42, 5580 (1990)] and also of M. Q. Bao et al. [Phys. Rev. A 58, 411 (1998)], is shown in this Comment to be incorrect. First, we point out that a number of assumptions of Rangan and Rau’s analysis rest on tenuous theoretical grounds. Second, we adduce two completely independent and different …

Invariant Spinor Representations Of Finite Rotation Matrices, N. L. Manakov, A. V. Meremianin, Anthony F. Starace

Anthony F. Starace Publications

Our recent results [N. L. Manakov et al., Phys. Rev. A 57, 3233 (1998); 61, 022103 (2000)] on the invariant representations of finite rotation matrices (FRM’s) of integer rank j (in terms of tensor products of vectors connected with a space-fixed reference frame) are generalized here for the general case of arbitrary (i.e., integer or half-integer) rank j. This extension is carried out by using new spinor representations of FRM’s in terms of specially introduced spinor-annihilation operators. We demonstrate that all widely used, standard representations of FRM’s follow as special cases of our invariant representation for particular parametrizations …

Revegetation Information And Training Needs Of Western Australia's Extension Intermediaries : A Qualitative And Quantitative Market Research Report, Stephen Lloyd

Agriculture reports

Report on a survey conducted in 2001 for the Department of Agriculture Western Australia's Farm Forestry and Revegetation (FF&R) Project, of 'Intermediaries', that is, those persons who mediate between those with expertise in revegetation and those who require the information. The survey was instigated in order to improve the flow, quality and utility of information as required by intermediaries, and to identify further training needs.

Large-Scale Power Spectrum And Structures From The Enear Galaxy Peculiar Velocity Catalogue, S. Zaroubi, M. Bernardi, L. N. Da Costa, Y. Hoffman, M. V. Alonso, G. Wegner

Dartmouth Scholarship

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiar velocity data of the recently completed redshift—distance survey of early-type galaxies (hereafter ENEAR). Parametric cold dark matter (CDM)-like models for the PS are assumed, and the best-fitting parameters are determined by maximizing the probability of the model given the measured peculiar velocities of the galaxies, their distances and estimated errors. The method has been applied to CDM models with and without COBE normalization. The general results are in agreement with the high-amplitude power spectra found from similar analyses of …

The First Detection Of Coherent Emission From Radio Pulsars, F. A. Jenet, S. B. Anderson, T. A. Prince

Physics and Astronomy Faculty Publications and Presentations

The statistical properties of the radio emission from the pulsars B0823+26, B0950+08, B1133+16, and B1937+21 are studied using high time resolution observations taken at the Arecibo Observatory in Puerto Rico. Temporally coherent non-Gaussian emission has been detected in three of the four observed objects. This is the first time such a phenomenon has been observed. The results have been interpreted using a generalized shot noise model, and various basic physical quantities pertaining to the magnetospheric plasma have been estimated.

Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

This paper addresses breast cancer diagnosis problem as a pattern classification problem. Specifically, the problem is studied using Wisconsin-Madison breast cancer data set. Fuzzy rules are generated from the input-output relationship so that the diagnosis becomes easier and transparent for both patients and physicians. For each class, at least one training pattern is chosen as the prototype, provided (a) the maximum membership of the training pattern is in the given class, and (b) among all the training patterns, the neighborhood of this training pattern has the least fuzzy-rough uncertainty in the given class. Using the fuzzy-rough uncertainty, a cluster is …

Virginia Boating Plan And Access Needs Assessment, Thomas J. Murray

Reports

In an effort to support Virginia's application for federal grant funds under the Department of Interior's "Boating Infrastructure Grant Program" (Grants), the Marina Technical Advisory Program (MT AP) at the Virginia Institute of Marine Science has undertaken assessment of the state's recreational boating infrastructure needs. 1 A total of $32 million has been authorized over four years to fund this new program. It is designed to help states develop and maintain facilities for transient non-trailerable (26' and over) recreational boats. The Virginia Department of Health (VDOH) has provided overall leadership in the Boating Infrastructure Grants process and has been supported …

Theater-Level Stochastic Air-To-Air Engagement Modeling Via Event Occurrence Networks Using Piecewise Polynomial Approximation, David R. Denhard

Theses and Dissertations

This dissertation investigates a stochastic network formulation termed an event occurrence network (EON). EONs are graphical representations of the superposition of several terminating counting processes. An EON arc represents the occurrence of an event from a group of (sequential) events before the occurrence of events from other event groupings. Events between groups occur independently, but events within a group occur sequentially. A set of arcs leaving a node is a set of competing events, which are probabilistically resolved by order relations. An important EON metric is the probability of being at a particular node or set of nodes at time …

Detecting Steganographic Messages In Digital Images, Hany Farid

Computer Science Technical Reports

Techniques and applications for information hiding have become increasingly more sophisticated and widespread. With high-resolution digital images as carriers, detecting the presence of hidden messages has also become considerably more difficult. It is sometimes possible, nevertheless, to detect (but not necessarily decipher) the presence of embedded messages. The basic approach taken here works by finding predictable higher-order statistics of ``natural'' images within a multi-scale decomposition, and then showing that embedded messages alter these statistics.