Physical Sciences and Mathematics Commons^™

Is The World Evolving Discretely?, Saber Elaydi

Mathematics Faculty Research

No abstract provided.

Multidentate Sulfur-Containing Ligands, David A. Atwood, Brock S. Howerton, Matthew Matlock

Chemistry Faculty Patents

Novel sulfur-containing ligands for binding of heavy metals are disclosed.

To read the remainder of this abstract, please download this patent.

Santa Clara Magazine, Volume 45 Number 1, Summer 2003, Santa Clara University

Santa Clara Magazine

8 - MASS APPEAL By Erin Ryan. Each week hundreds of students close their books for the night and crowd into Mission Santa Clara for an informal 10 p.m. Mass. The service has drawn students and the community to church for more than 30 years.

10 - BREAKING THROUGH By Francisco Jimenez. An excerpt from the autobiography of Jimenez, who faced many challenges since he and his family entered the United States from Mexico when he was 4. Through work in the fields, to deportation, to struggles in English class, he persevered. And now he's a professor at SCU.

16 …

On The Stability Of The Positive Radial Steady States For A Semilinear Cauchy Problem, Yinbin Deng, Yi Li, Yi Liu

Mathematics and Statistics Faculty Publications

No abstract provided.

On Adaptive Estimation In Orthogonal Saturated Designs, Weizhen Wang, Daniel T. Voss

Mathematics and Statistics Faculty Publications

A simple method is provided to construct a general class of individual and simultaneous confidence intervals for the effects in orthogonal saturated designs. These intervals use the data adaptively, maintain the confidence levels sharply at 1 - α at the least favorable parameter configuration, work effectively under effect sparsity, and include the intervals by Wang and Voss (2001) as a special case.

Rotational Velocities Of B, A, And Early‐F Narrow‐Lined Stars, Francis C. Fekel

Information Systems and Engineering Management Research Publications

Projected rotational velocities for 58 B, A, and early‐F stars have been determined from high‐resolution spectroscopic observations made at Kitt Peak National Observatory with the coudé feed telescope. All the stars are slowly rotating with vsin i<60 km s−1. Because of their low rotational velocities, 15 of the stars have been observed as prospective, early‐type, radial velocity standards.

Pks 0736+017: A Striking Optical Flare And Intriguing Microvariability, Sandra D. Clements, A Jenks, Y Torres

Aerospace, Physics, and Space Science Faculty Publications

The compact, flat-spectrum radio quasar PKS 0736+017 was monitored for microvariability on 10 nights in early 2002 using the 0.9 m SARA telescope on Kitt Peak in Arizona. On January 14, PKS 0736+017 flared dramatically, brightening by 1.3 R mag in 2 hours. Prior to the flare, PKS 0736+017 exhibited quasi-periodic variations. During and after the flare, more complex oscillations occurred. Impressive variability was displayed on two additional nights in January, while observations during the following 3 months found PKS 0736+017 to be fairly quiescent. PKS 0736+017 was somewhat redder while brighter and fading than when dimmer but flaring. During …

The Positive Model For Offshore Team Teaching, Penelope Mcfarlane, A. Fuller, K. Lam

Faculty of Informatics - Papers (Archive)

Like many western universities, the University of Wollongong is offering degrees to an increasing number of offshore students. Our usual offshore teaching model involves intensive delivery of course material. Disadvantages of this model include the brevity of student contact with the UOW academic and delays in response to student questions and concerns regarding the subject. We discuss some results of an experiment using inexpensive and readily available Internet technologies to overcome those disadvantages.

Improved Antenna Selection Technique To Enhance The Performance Of Wireless Communications Channels, Le Chung Tran, Tadeusz A. Wysocki, Alfred Mertins

Faculty of Informatics - Papers (Archive)

The combination of space-time codes and a closed loop transmission diversity technique is currently receiving a lot of attention since it allows one to improve the performance of wireless communications channels. This paper proposes a simple closed loop transmission diversity technique to improve further the performance of the channels through proposing a structure of feedback information in order to reduce the time required for processing the feedback information at the transmitter. Calculations and simulations show that our technique performs especially well when it is combined with the Alamouti code.

Scalable Speech Coding Spanning The 4 Kbps Divide, J Lukasiak, I. Burnett

Faculty of Informatics - Papers (Archive)

This paper examines a scalable method for coding the LP residual. The scalable method is capable of increasing the accuracy of the reconstructed speech from a parametric representation at low rates to a more accurate waveform matched representation at higher rates. The method entails pitch length segmentation, decomposition into pulsed and noise components and modeling of the pulsed components using a fixed shape pulse model in a closed-loop, Analysis by Synthesis system. Subjective testing is presented that indicates that in addition to the AbyS modeling, the pulse parameter evolution must be constrained in synthesis. Results indicate that this proposed method …

Low Bit Rate Wideband Wi Speech Coding, C. H. Ritz, I. Burnett, Jason Lukasiak

Faculty of Informatics - Papers (Archive)

This paper investigates waveform interpolation (WI) applied low bit rate wideband speech coding. An analysis of the evolutionary behaviour of wideband characteristic waveforms (CWs) shows that direct application of the classical WI algorithm may not be appropriate for wideband speech. We propose a modification whereby CW quantisation is performed using classical WI decomposition for the low frequency region and noise modelling for the high frequency region. Wideband WI coders incorporating this modification and operating at 4 kbps and 6 kbps are described. Subjective testing of these coders shows that WI is a promising approach to low bit rate wideband speech …

Multi-Rate And Multi-Resolution Scalable To Lossless Audio Compression Using Pspiht, M. Raad, I. Burnett, Alfred Mertins

Faculty of Informatics - Papers (Archive)

This paper presents a scalable to lossless compression scheme that allows scalability in terms of sampling rate as well as quantization resolution. The scheme presented is perceptually scalable and it also allows lossless compression. The scheme produces smooth objective scalability, in terms of SNR, until lossless compression is achieved. The scheme is built around the perceptual SPIHT algorithm, which is a modification of the SPIHT algorithm. Objective and subjective results are given that show perceptual as well as objective scalability. The subjective results given also show that the proposed scheme performs comparably with the MPEG-4 AAC coder at 16, 32 …

An Extended Acdc Algorithm For The Blind Estimation Of Convolutive Mixing Systems, Alfred Mertins, I. Russell

Faculty of Informatics - Papers (Archive)

This paper presents an extension of the ACDC algorithm introduced by Yeredor for the instantaneous mixing problem to the more general convolutive mixing problem with non-white sources. Further assumptions made on the source signals are their mutual statistical independence, nonstationarity and smoothness of their power spectra. The algorithm iterates the estimation of the mixing system (AC step) and the source statistics (DC step) until convergence is achieved. The proposed algorithm operates in the frequency domain, but unlike most frequency domain algorithms, it carries out some of the operations jointly for all frequencies. This allows us to overcome frequency dependent permutation …

The Maximal Determinant And Subdeterminants Of ±1 Matrices, Jennifer Seberry, Tianbing Xia, C. Koukouvinos, M. Mitrouli

Faculty of Informatics - Papers (Archive)

In this paper we study the maximal absolute values of determinants and subdeterminants of ±1 matrices, especially Hadamard matrices. It is conjectured that the determinants of ±1 matrices of order n can have only the values k • p, where p is specified from an appropriate procedure. This conjecture is verified for small values of n. The question of what principal minors can occur in a completely pivoted ±1 matrix is also studied. An algorithm to compute the (n — j) x (n — j), j = 1, 2, ... minors of Hadamard matrices of order n is presented, and …

Some Results On Self-Orthogonal And Self-Dual Codes, S. Georgiou, C. Koukouvinos, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

We use generator matrices G satisfying GGT = aI+bJ over Zk to obtain linear self-orthogonal and self-dual codes. We give a new family of linear self-orthogonal codes over GF(3) and Z4 and a new family of linear self-dual codes over GF(3).

Generalized Bhaskar Rao Designs With Block Size 4 Signed Over Elementary Abelian Groups , G. Ge, M. Greig, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

de Launey and Seberry have looked at the existence of Generalized Bhaskar Rao designs with block size 4 signed over elementary Abelian groups and shown that the necessary conditions for the existence of a (v, 4, λ; EA(g)) GBRD are sufficient for λ > g with 70 possible exceptions. This article extends that work by reducing those possible exceptions to just a (9,4,18h; EA(9h)) GBRD, where gcd(6, h) = 1, and shows that for λ = g the necessary conditions are sufficient for v > 46.

Distributed Clustering For Scalable, Long-Lived Sensor Networks, Ossama Younis, Sonia Fahmy

Department of Computer Science Technical Reports

No abstract provided.

Record Linkage: A Machine Learning Approach, A Toolbox, And A Digital Government Web Service, Mohamed G. Elfeky, Vassilios S. Verykios, Ahmed K. Elmagarmid, Thanaa M. Ghanem, Ahmed R. Huwait

Department of Computer Science Technical Reports

No abstract provided.

Level Compressed Dags For Lookup Tables, Ioannis Ioannidis, Ananth Y. Grama

Department of Computer Science Technical Reports

No abstract provided.

On Monitoring And Controlling Qos Network Domains, Ahsan Habib, Sonia Fahmy, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.

Robust Regression With High Coverage, David J. Olive, Douglas M. Hawkins

Articles and Preprints

An important parameter for several high breakdown regression algorithm estimators is the number of cases given weight one, called the coverage of the estimator. Increasing the coverage is believed to result in a more stable estimator, but the price paid for this stability is greatly decreased resistance to outliers. A simple modification of the algorithm can greatly increase the coverage and hence its statistical performance while maintaining high outlier resistance.

Scwds Briefs: Volume 19, Number 2 (July 2003)

Southeastern Cooperative Wildlife Disease Study: Publications

• CWD Surveillance in the Southeast: The discovery of chronic wasting disease (CWD) in wild deer remote from the historic endemic area in Colorado and Wyoming has fueled concerns among wildlife agencies over the distribution of the disease.
• Monkeypox Introduced with Exotic Pets: During June and July 2003, 72 suspected human cases of monkeypox were reported in Illinois, Indiana, Kansas, Missouri, Ohio, and Wisconsin (37 confirmed).
• SARS: In February 2003, a new coronaviral disease known as Severe Acute Respiratory Syndrome (SARS) gained international attention as it spread to 32 countries around the world.
• Florida Fish and Wildlife …

Frequency Scanned Interferometer Demonstration System, Tim Blass, Jason A. Deibel, Sven Nyberg, Keith Riles, Haijun Yang

Physics Faculty Publications

No abstract provided.

A Rapid Assessment Of Coral Reefs Near Hopetown, Abaco Islands, Bahamas (Stony Corals And Algae), Joshua Feingold, Susan L. Thornton, Kenneth W. Banks, Nancy J. Gasman, David S. Gilliam, Pamela Fletcher, Christian L. Avila

Marine & Environmental Sciences Faculty Articles

Coral reefs at 13 sites ranging in depth from 1-16 m near Hopetown, Abaco Islands, Bahamas were surveyed utilizing the Atlantic and Gulf Rapid Reef Assessment (AGRRA) benthos protocol. A total of 35 species of scleractinian corals and 2 species of calcareous hydrocorals were observed. The overall coral cover averaged just over 14%. Among corals that were at least 10 cm in diameter, small colonies (< 40 cm diameter) predominated in all sites except for the Fowl Cay pinnacles where 68% were larger than 60 cm in diameter. Large colonies (> 40 cm diameter) were also found in the Lynyard Cay spur-and-groove formations and the Sandy Cay fore reef. Zero-4% of the colonies were affected by disease. Total (recent + old) partial-colony mortality ranged from …

Performance Of Mpeg-7 Low Level Audio Descriptors With Compressed Data, Jason Lukasiak, David A. Stirling, N. Harders, S. Perrow

Faculty of Informatics - Papers (Archive)

This paper presents a detailed analysis of lossy compression effects on a set of the MPEG-7 low-level audio descriptors. The analysis results show that lossy compression has a detrimental effect on the integrity of practical search and retrieval schemes that utilize the low level audio descriptors. Methods are then proposed to reduce the detrimental effects of compression in searching schemes. These proposed methods include multi-frame searching and machine learning derived prediction. The proposed mechanisms greatly reduce the effect of compression on the set of MPEG-7 descriptors; however, future scope is identified to develop new audio descriptors that account for compression …

Scalable To Lossless Audio Compression Based On Perceptual Set Partitioning In Hierarchical Trees (Pspiht), M. Raad, Alfred Mertins, I. Burnett

Faculty of Informatics - Papers (Archive)

This paper proposes a technique for scalable and also provides for lossless compression. It reduces smooth objective scalability, in terms of SegSNR, from lossy to lossless compression. The proposal is built around the perceptual SPIHT algorithm, which is a modification of the SPIHT algorithm and is introduced in this paper. Both objective and subjective results are reported and demonstrate that the proposed method performs comparably with the MPEG-4 AAC coder at 16, 32 and 64 kbps, yet also achieves a scalable-to-lossless architecture.

Violin: Virtual Internetworking On Overlay Infrastructure, Xuxian Jiang, Dongyan Xu

Department of Computer Science Technical Reports

No abstract provided.

Bulk And Interfacial Properties Of A Dipolar-Quadrupolar Fluid In A Uniform Electric Field: A Density-Functional Approach, V.B. Warshavsky, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

We have studied the bulk and interfacial properties of a dipolar-quadrupolar fluid based on an extended modified mean-field density-functional theory. Effects of a uniform electric field on the bulk and interfacial properties are also studied. Results of the coexisting vapor-liquid densities, interfacial profiles of the density and orientation order parameters, the surface tension, and their dependence on the temperature, magnitude of molecule dipole and quadrupole moment, and the applied field are obtained. In general, we find that the applied field increases the critical temperature, broadens the vapor-liquid coexistence curves, and reduces the surface tension. We also find that if the …

Extrapolation Of The Zα-Expansion And Two-Loop Bound-State Energy Shifts, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Quantum electrodynamic (QED) effects that shift the binding energies of hydrogenic energy levels have been expressed in terms of a semi-analytic expansion in powers of Zα and ln[(Zα)^-2], where Z is the nuclear charge number and α is the fine-structure constant. For many QED effects, numerical data are available in the domain of high Z where the Zα expansion fails. In this Letter, we demonstrate that it is possible, within certain limits of accuracy, to extrapolate the Zα-expansion from the low-Z to the high-Z domain. We also review two-loop self-energy effects and provide an estimate for the problematic …

Comment On: 'Depolarization Corrections To The Coercive Field In Thin-Film Ferroelectrics', Stephen Ducharme, Vladimir Fridkin

Stephen Ducharme Publications

The Letter by Dawber et al. [J. Phys.: Condens. Matter 15 L393 (2003)] notes that incomplete screening in the electrodes of a ferroelectric capacitor can result in an underestimate for the true coercive field in films of nanometer thickness. We show that their estimate of the magnitude of this correction it too large in the case of ferroelectric copolymer Langmuir- Blodgett films and, as a result, invalidates the claim that finite-size scaling of the ferroelectric coercive field is evident in films thinner than 15 nm.