Physical Sciences and Mathematics | Open Access Articles

Little Venice Water Quality Monitoring Annual Report, Ronald Jones, Joseph N. Boyer

SERC Research Reports

No abstract provided.

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Studies Of The Relationship Between The Structure And Properties Of Interfacial Thin Films, Mark Anderson

Mark R. Anderson

No abstract is available at this time.

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Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Ii. The Minor Axis Dataset, G. Wegner, E. M. Corsini, R. P. Saglia, R. Bender

Dartmouth Scholarship

We present minor axis, offset major axis and one diagonal long slit spectra for 10 E and S0 galaxies of the Coma cluster drawn from a magnitude-limited sample studied before. We derive rotation curves, velocity dispersion profiles and the H3 and H4 coefficients of the Hermite decomposition of the line of sight velocity distribution. Moreover, we derive the line index profiles of Mg, Fe and Hβ line indices and assess their errors. The data will be used to construct dynamical models of the galaxies and study their stellar populations.

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Examination Of The 500,000-Year Climate Record In Ice At Mt. Moulton, West Antarctica, Gregory A. Zielinski, Paul Andrew Mayewski

University of Maine Office of Research Administration: Grant Reports

This project was a pilot project to determine if the ice on Mt. Moulton provides a reliable record of past climatic conditions. The area of study is a several hundred-meter section of blue ice (Trench A) that spans the time period from approximately the early Holocene to over 492k years ago. Dating control is obtained through radiometrically-dated tephra layers (i.e., air fall deposits) within the section (Figure 1) originating from the adjacent Mt. Berlin. Fieldwork during the 1999-2000 field season included the trenching of the complete section with electric chain saws mounted on a wheeled frame. Blocks were extracted and …

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Oxidation Of Metals At The Chromium Oxide Interface, Ruihua Cheng, C.N. Borca, N. Pilet, Bo Xu, Lu Yuan, Bernard Doudin, Sy_Hwang Liou, Peter A. Dowben

Peter Dowben Publications

Metal thin-film deposition, over the Cr₂O₃ surface of CrO₂ thin-film substrates, exhibits a redox reaction at the interface. The transition metal forms an oxide in combination with the reduction of the near-surface chromium oxide to Cr₂O₃ . The insulating barrier layer Cr₂O₃ increases with the formation of Pb₃ O₄ in Pb/Cr₂O₃ /CrO₂ and CoO in Co/Cr₂O₃ /CrO₂ junctions, respectively.

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Imaging And Engineering The Nanoscale-Domain Structure Of A Sr0.61Ba0.39Nb2O6 Crystal Using A Scanning Force Microscope, K. Terabe, S. Takekawa, M. Nakamura, K. Kitamura, Alexei Gruverman

Alexei Gruverman Publications

We have investigated the ferroelectric domain structure formed in a Sr_0.61Ba_0.39Nb₂O₆ single crystal by cooling the crystal through the Curie point. Imaging the etched surface structure using a scanning force microscope (SFM) in both the topographic mode and the piezoresponse mode revealed that a multidomain structure of nanoscale island-like domains was formed. The island-like domains could be inverted by applying an appropriate voltage using a conductive SFM tip. Furthermore, a nanoscale periodically inverted-domain structure was artificially fabricated using the crystal which underwent poling treatment.

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Prairie Dogs And The Prairie Ecosystem, Scott E. Hygnstrom, Dallas R. Virchow

School of Natural Resources: Faculty Publications

Prairie dogs play an important role in the prairie ecosystem by creating unique patches of habitat in the expansive prairies of the American West. Their daily activities change the physical characteristics of the community, which leads to increased plant and animal diversity. Prairie dogs are a source of food for several predators, and their burrows provide homes for a variety of species, including the burrowing owl and endangered black-footed ferret. They also provide recreational opportunities for nature observers, photographers, and the sporting public. The presence of large, healthy prairie dog towns, however, is not always compatible with agriculture and other …

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Why Prefer Double Robust Estimates? Illustration With Causal Point Treatment Studies, Romain Neugebauer, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

In point treatment marginal structural models with treatment A, outcome Y and covariates W, causal parameters can be estimated under the assumption of no unobserved confounders. Three estimates can be used: the G-computation, Inverse Probability of Treatment Weighted (IPTW) or Double Robust (DR) estimates. The properties of the IPTW and DR estimates are known under an assumption on the treatment mechanism that we name "Experimental Treatment Assignment" (ETA) assumption. We show that the DR estimating function is unbiased when the ETA assumption is violated if the model used to regress Y on A and W is correctly specified. The practical …

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An Extension Of Elton's L(1)(N) Theorem To Complex Banach Spaces, S J. Dilworth, Joseph P. Patterson

Faculty Publications

No abstract provided.

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Bivariate Current Status Data, Mark J. Van Der Laan, Nicholas P. Jewell

U.C. Berkeley Division of Biostatistics Working Paper Series

In many applications, it is often of interest to estimate a bivariate distribution of two survival random variables. Complete observation of such random variables is often incomplete. If one only observes whether or not each of the individual survival times exceeds a common observed monitoring time C, then the data structure is referred to as bivariate current status data (Wang and Ding, 2000). For such data, we show that the identifiable part of the joint distribution is represented by three univariate cumulative distribution functions, namely the two marginal cumulative distribution functions, and the bivariate cumulative distribution function evaluated on the …

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Current Status Data: Review, Recent Developments And Open Problems, Nicholas P. Jewell, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Researchers working with survival data are by now adept at handling issues associated with incomplete data, particular those associated with various forms of censoring. An extreme form of interval censoring, known as current status observation, refers to situations where the only available information on a survival random variable T is whether or not T exceeds a random independent monitoring time C. This article contains a brief review of the extensive literature on the analysis of current status data, discussing the implications of response-based sampling on these methods. The majority of the paper introduces some recent extensions of these ideas to …

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Creating Nanocavities Of Tunable Sizes: Hollow Helices, Bing Gong, Huaqiang Zeng, Jin Zhu, Lihua Yuan, Yaohua Han, Shizhi Cheng, Mako Furukawa, Ruben D. Parra, Audrey Y. Kovalevsky, Jeffrey L. Mills, Ewa Skrzypczak-Jankun, Suzana Martinovic, Richard D. Smith, Chong Zheng, Thomas Szyperski, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A general strategy for creating nanocavities with tunable sizes based on the folding of unnatural oligomers is presented. The backbones of these oligomers are rigidified by localized, threecenter intramolecular hydrogen bonds, which lead to well-defined hollow helical conformations. Changing the curvature of the oligomer backbone leads to the adjustment of the interior cavity size. Helices with interior cavities of 10 Å to >30 Å across, the largest thus far formed by the folding of unnatural foldamers, are generated. Cavities of these sizes are usually seen at the tertiary and quaternary structural levels of proteins. The ability to tune molecular dimensions …

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A Posteriori Error Estimates Based On Polynomial Preserving Recovery, Zhimin Zhang, Ahmed Naga

Mathematics Research Reports

Superconvergence of order O(h^1+rho), for some rho is greater than 0, is established for gradients recovered using Polynomial Preserving Recovery technique when the mesh is mildly structured. Consequently this technique can be used in building a posteriori error estimator that is asymptotically exact.

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A Mechanical System For Soil Reconstruction, John Patrick Fulton, Larry G. Wells, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

One of the most perplexing problems associated with reclaiming surface–mined lands is excessive compaction of soil due to the heavy earthmoving equipment used during the reclamation process. Over the years, some innovative material handling schemes have been devised to limit vehicle traffic during reclamation on reconstructed soil. However, final grading operations can often create root–limiting bulk densities, which affect plant growth and yield. The purpose of this article is to describe a mechanism designed at the University of Kentucky whereby mine soil can be reconstructed without introducing compaction caused by surface traffic in order for the soil to sustain desirable …

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Using Composition Techniques To Improve Classroom Instruction And Students’ Understanding Of Proof, Christopher D. Goff

College of the Pacific Faculty Articles

This paper describes an effort to incorporate standard composition exercises into a sophomore-level discrete mathematics class. It provides an example of how peer review can be integrated with a mathematical curriculum through the writing of proofs.

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The Meowplex: A New Dna Test Using Tetranucleotide Str Markers For The Domestic Cat, John M. Butler, Victor A. David, Stephen J. O'Brien, Marilyn Menotti-Raymond

Biology Faculty Articles

No abstract provided.

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Nanoscale Observation Of Photo-Induced Domain Pinning And Investigation Of Imprint Behavior In Ferroelectric Thin Films, Alexei Gruverman, B. J. Rodriguez, R. J. Nemanich, A. I. Kingon

Alexei Gruverman Publications

Piezoresponse force microscopy has been used to investigate the nanoscale mechanism of imprint behavior of ferroelectric PbTiO₃ thin films by studying the photoinduced changes in the hysteresis loops of individual grains. Illumination of the film with UV light resulted in a voltage shift opposite to that observed in ferroelectric thin film capacitors. This effect is attributed to the generation of an electric field within the surface dielectric layer as a result of the interaction between photo-induced charges and polarization charges. Application of a small non-switching bias to the film with simultaneous UV illumination resulted in domain pinning in …

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Globally Distributed Content Delivery, John Dilley, Bruce Maggs, Jay Parikh, Harald Prokop, Ramesh Sitaraman, Bill Weihl

Ramesh Sitaraman

No abstract provided.

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A Bayesian Analysis Involving Colonic Crypt Structure And Coordinated Response To Carcinogens Incorporating Missing Crypts, Jeffrey S. Morris, Naisyin Wang, Joanne R. Lupton, Robert S. Chapkin, Nancy D. Turner, Mee-Young Hong, Raymond J. Carroll

Jeffrey S. Morris

This paper is concerned with modeling the architecture of colonic crypts and the implications of this modeling for understanding possible coordinated response of carcinogen–induced DNA damage between various regions of the colon. The methods we develop to address these two issues are applied to a particular important example in colon carcinogenesis. We cast the problem as an unusual and not previously studied hierarchical mixed-effects model characterized by completely missing covariates in units at a structurally base level, except for some randomly selected units. Information concerning the missing covariates is available through certain known ordering constraints and surrogate measures. Our methods …

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Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville

Ted K. Raab

The plant genes required for the growth and reproduction of plant pathogens are largely unknown. In an effort to identify these genes, we isolated Arabidopsis mutants that do not support the normal growth of the powdery mildew pathogen Erysiphe cichoracearum. Here, we report on the cloning and characterization of one of these genes, PMR6. PMR6 encodes a pectate lyase-like protein with a novel C-terminal domain. Consistent with its predicted gene function, mutations in PMR6 alter the composition of the plant cell wall, as shown by Fourier transform infrared spectroscopy. pmr6-mediated resistance requires neither salicylic acid nor the ability to perceive …

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3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder

Otto Vogl

No abstract provided.

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Digital Image Similarity For Geo-Spatial Knowledge Management, James Carswell

Conference papers

The amount and availability of high-quality geo-spatial image data, such as digital satellite and aerial photographs, is increasing dramatically. Task-based management of such visual information and associated knowledge is a central concern for organisations that rely on digital imagery. We are developing geo-spatial knowledge management techniques that employ case-based reasoning as the core methodology. In order to provide effective retrieval of task-based experiences that center around geo-spatial imagery, we need to forward novel similarity metrics for directly comparing the image components of experience cases. Based on work in geo-spatial image database retrieval, we are building an effective similarity metric for …

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Manejo De La Cotorra En Instalaciones Eléctricas En El Sur De Florida, Michael L. Avery, Ellis C. Greiner, James R. Lindsay, James R. Newman, Stephen Pruett-Jones

Vertebrate Pest Conference: Spanish-Language Materials

La cotorra común (Myiopsitta monachus) es un ave originaria de América del Sur pero se ha establecido en varios sitios a lo largo de los Estados Unidos mediante liberaciones premeditadas y también accidentales. La especie es única entre los loros pues no construye sus nidos en cavidades sino que construye una estructura de nidificación voluminosa con palos. A menudo, tanto en regiones donde es nativa y en los Estados Unidos, la cotorra selecciona las estructuras eléctricas como sitio de nidificación. El material del nido puede causar corto-circuitos que producen daños a la estructura y cortes de luz subsiguientes. En el …

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Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien

Computer Science Technical Reports

Understanding usage patterns in wireless local-area networks (WLANs) is critical for those who develop, deploy, and manage WLAN technology, as well as those who develop systems and application software for wireless networks. This paper presents results from the largest and most comprehensive trace of network activity in a large, production wireless LAN. For eleven weeks we traced the activity of nearly two thousand users drawn from a general campus population, using a campus-wide network of 476 access points spread over 161 buildings. Our study expands on those done by Tang and Baker, with a significantly larger and broader population. We …

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Monte Carlo Simulation On The Indirect Exchange Interactions Of Co-Doped Zno Film, Scott Whittenburg

Chemistry Faculty Publications

Monte Carlo simulations using a three-dimensional lattice model studied the Ruderman–Kittel–Kasuya–Yosida (RKKY) indirect exchange interaction of doped magnetic Co ions in ZnO films. The results of the calculations show that the RKKY interaction in Co-doped ZnO is long ranged and its magnitude is proportional to R⁻¹ (inverse of the distance R from a central Co²⁺ ion). The sign oscillates with a frequency that depends on the concentration of the carrier. The long-distance sum of the RKKY indirect exchange energies is positive indicating that these materials are ferromagnetic, in direct correlation with previously reported results

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Writing Mathematics-A Nut And A Bolt Of Style, Frank A. Farris

Mathematics and Computer Science

As editor of Mathematics Magazine, I see a lot of manuscripts. Some of them are written with a charming sense of style, but many of them leave me thinking that the author's only concern was to set out the mathematics clearly. This is a fine place to start, but the tradition of the Magazine is to offer things that people will enjoy reading, and this requires more than clarity. Let me explain an important step authors can take in order to make their work more attractive.

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Matroid Duality From Topological Duality In Surfaces Of Nonnegative Euler Characteristic, Dan Slilaty

Mathematics and Statistics Faculty Publications

Let G be a connected graph that is 2-cell embedded in a surface S, and let G* be its topological dual graph. We will define and discuss several matroids whose element set is E(G), for S homeomorphic to the plane, projective plane, or torus. We will also state and prove old and new results of the type that the dual matroid of G is the matroid of the topological dual G*.

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Six New Γ Doradus Stars, Gregory W. Henry, Francis C. Fekel

Information Systems and Engineering Management Research Publications

We present high‐resolution spectroscopy and precision photometry of six new γ Doradus stars, one of which was independently discovered by another group. This brings the total number of confirmed γ Doradus variables to 30. All six of these variables fall in the spectral class range F0–F2; all but one are subgiants. The six stars have between one and five photometric periods in the range 0.3–1.2 days. We find no evidence for higher frequency δ Scuti pulsations in any of these six stars. Our spectroscopic observations reveal HD 108100 to be the first confirmed γ Doradus variable with composite broad and …

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Seafloor Video Mapping: Modeling, Algorithms, Apparatus, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.

Center for Coastal and Ocean Mapping

This paper discusses a technique used for construction of high-resolution image mosaic from a videosequence and the synchronously logged camera attitude information. It allows one to infer geometric characteristics of the imaged terrain and hence improve the mosaic quality and reduce the computational burden. The technique is demonstrated using numerical modeling and is applied to videodata collected on Rainsford Island, Mass. Calculation of the transformation relating consecutive image frames is an essential operation affecting reliability of the whole mosaicing process. Improvements to the algorithm are suggested, which significantly decrease the possibility of convergence to an inappropriate solution.

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Highly Scalable Image Compression Based On Spiht For Network Applications, H. Danyali, Alfred Mertins

Faculty of Informatics - Papers (Archive)

We propose a highly scalable image compression scheme based on the set partitioning in hierarchical trees (SPIHT) algorithm. Our algorithm, called highly scalable SPIHT (HS-SPIHT), supports spatial and SNR scalability and provides a bitstream that can be easily adapted (reordered) to given bandwidth and resolution requirements by a simple transcoder (parser). The HS-SPIHT algorithm adds the spatial scalability feature without sacrificing the SNR embeddedness property as found in the original SPIHT bitstream. HS-SPIHT finds applications in progressive Web browsing, flexible image storage and retrieval, and image transmission over heterogeneous networks.

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Full-Text Articles in Physical Sciences and Mathematics

Little Venice Water Quality Monitoring Annual Report, Ronald Jones, Joseph N. Boyer

SERC Research Reports

Studies Of The Relationship Between The Structure And Properties Of Interfacial Thin Films, Mark Anderson

Mark R. Anderson

Spatially Resolved Spectroscopy Of Coma Cluster Early-Type Galaxies - Ii. The Minor Axis Dataset, G. Wegner, E. M. Corsini, R. P. Saglia, R. Bender

Dartmouth Scholarship

Examination Of The 500,000-Year Climate Record In Ice At Mt. Moulton, West Antarctica, Gregory A. Zielinski, Paul Andrew Mayewski

University of Maine Office of Research Administration: Grant Reports

Oxidation Of Metals At The Chromium Oxide Interface, Ruihua Cheng, C.N. Borca, N. Pilet, Bo Xu, Lu Yuan, Bernard Doudin, Sy_Hwang Liou, Peter A. Dowben

Peter Dowben Publications

Imaging And Engineering The Nanoscale-Domain Structure Of A Sr0.61Ba0.39Nb2O6 Crystal Using A Scanning Force Microscope, K. Terabe, S. Takekawa, M. Nakamura, K. Kitamura, Alexei Gruverman

Alexei Gruverman Publications

Prairie Dogs And The Prairie Ecosystem, Scott E. Hygnstrom, Dallas R. Virchow

School of Natural Resources: Faculty Publications

Why Prefer Double Robust Estimates? Illustration With Causal Point Treatment Studies, Romain Neugebauer, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

An Extension Of Elton's L(1)(N) Theorem To Complex Banach Spaces, S J. Dilworth, Joseph P. Patterson

Faculty Publications

Bivariate Current Status Data, Mark J. Van Der Laan, Nicholas P. Jewell

U.C. Berkeley Division of Biostatistics Working Paper Series

Current Status Data: Review, Recent Developments And Open Problems, Nicholas P. Jewell, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Xiao Cheng Zeng Publications

A Posteriori Error Estimates Based On Polynomial Preserving Recovery, Zhimin Zhang, Ahmed Naga

Mathematics Research Reports

A Mechanical System For Soil Reconstruction, John Patrick Fulton, Larry G. Wells, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

Using Composition Techniques To Improve Classroom Instruction And Students’ Understanding Of Proof, Christopher D. Goff

College of the Pacific Faculty Articles

The Meowplex: A New Dna Test Using Tetranucleotide Str Markers For The Domestic Cat, John M. Butler, Victor A. David, Stephen J. O'Brien, Marilyn Menotti-Raymond

Biology Faculty Articles

Nanoscale Observation Of Photo-Induced Domain Pinning And Investigation Of Imprint Behavior In Ferroelectric Thin Films, Alexei Gruverman, B. J. Rodriguez, R. J. Nemanich, A. I. Kingon

Alexei Gruverman Publications

Globally Distributed Content Delivery, John Dilley, Bruce Maggs, Jay Parikh, Harald Prokop, Ramesh Sitaraman, Bill Weihl

Ramesh Sitaraman

A Bayesian Analysis Involving Colonic Crypt Structure And Coordinated Response To Carcinogens Incorporating Missing Crypts, Jeffrey S. Morris, Naisyin Wang, Joanne R. Lupton, Robert S. Chapkin, Nancy D. Turner, Mee-Young Hong, Raymond J. Carroll

Jeffrey S. Morris

Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville

Ted K. Raab

3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder

Otto Vogl

Digital Image Similarity For Geo-Spatial Knowledge Management, James Carswell

Conference papers

Manejo De La Cotorra En Instalaciones Eléctricas En El Sur De Florida, Michael L. Avery, Ellis C. Greiner, James R. Lindsay, James R. Newman, Stephen Pruett-Jones

Vertebrate Pest Conference: Spanish-Language Materials

Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien

Computer Science Technical Reports

Monte Carlo Simulation On The Indirect Exchange Interactions Of Co-Doped Zno Film, Scott Whittenburg

Chemistry Faculty Publications

Writing Mathematics-A Nut And A Bolt Of Style, Frank A. Farris

Mathematics and Computer Science

Matroid Duality From Topological Duality In Surfaces Of Nonnegative Euler Characteristic, Dan Slilaty

Mathematics and Statistics Faculty Publications

Six New Γ Doradus Stars, Gregory W. Henry, Francis C. Fekel

Information Systems and Engineering Management Research Publications

Seafloor Video Mapping: Modeling, Algorithms, Apparatus, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.

Center for Coastal and Ocean Mapping

Highly Scalable Image Compression Based On Spiht For Network Applications, H. Danyali, Alfred Mertins

Faculty of Informatics - Papers (Archive)