Physical Sciences and Mathematics Commons^™

The Crest, Fall 2003, Virginia Institute Of Marine Science

Reports

Table of Contents:

• VIMS hires new Dean and Director
• Hurricane Isabel hinders research
• VIMS acquires unique new vessel
• Pair pursue promise of proteomics
• Research questions environmental safety of flame retardant
• VIMS scientists quantify Isabel's impact on Bay
• Schaffner Elected ERF President
• ABC continues oyster work with Academy validation
• Newman wins SETAC Founders Award
• Faculty help bring minorities to marine science
• Sea Grant sponsors seafood education programs
• VIMS hosts international sediment conference
• Students chosen as Knauss Fellows
• Aquanauts visit inner space
• Study highlights link between biodiversity and ecosystem function
• CCRM kicks off trans-Atlantic collaboration

Waterfront Development And Potential Impacts To Aquatic Habitat A Planning Tool For Evaluating Resource Sensitivity, Marcia Berman, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.

Wind-Induced Exchange In Semi-Enclosed Basins, Rosario Sanay

OES Theses and Dissertations

The wind-induced circulation over laterally varying bathymetry was investigated in homogeneous and in stratified systems using the three-dimensional Regional Ocean Model (ROMS). For homogeneous systems, the focus was to describe the influence of the earth's rotation on the lateral distribution of the flow with particular emphasis on the transverse circulation. Along-basin wind-stress with no rotation caused a circulation dominated by an axially symmetric transverse structure consisting of downwind flow over the shoals and upwind flow in the channel along the whole domain. Transverse circulation was important only at the head of the system where the water sank and reversed direction …

Dissolved Humic Substances: Characterization Of Their Sorption Onto Iron Hydroxide Aluminum Hydroxide Kaolinite And Smectite, Sarah E. Diebel

OES Theses and Dissertations

Humic (HA) and fulvic (FA) acids participate in many geochemical processes and the mechanisms of their sorption to colloidal surfaces are numerous, indicating these substances are complex and heterogeneous. The current study focuses on the interactions of the Fe hydroxide (FE), Al hydroxide, Kaolinite (KA) and Smectite (SM) and these naturally occurring organic acids using Fourier Transform Infrared Spectroscopy (FTIR) and DOC analysis at pH 4. FTIR was used for the initial functional group characterization, as well as the comparison of before and after adsorption spectra of the HA and FA. DOC examined the amounts of HA and FA adsorbed …

Targeting The Transcriptional Machinery With Unique Artificial Transcriptional Activators, Brian Brennan, Zhiqian Wu, Garrette Belanger, Jenifer Lum, Aaron Minter, Steven Rowe, Annette Plachetka, Chinmay Majmudar, Anna Mapp

Brian B. Brennan

The link between a growing number of human diseases and misregulation of gene expression has spurred intense interest in artificial transcriptional activators that could be used to restore controlled expression of affected genes. To expand the repertoire of activation domains available for the construction of artificial transcriptional regulators, a selection strategy was used to identify two unique activation domain motifs. These activation domains bear little sequence homology to endogenous counterparts and bind to unique sites within the transcriptional machinery. A comparison with two well-characterized activation domains, VP2 and P201, demonstrated for the first time that functional potency is not solely …

Removal Of Organic Droplets From Metal Surfaces Using An Applied Electric Potential, Samuel Morton, R. Counce, D. Keffer, D. Depaoli, M. Hu

Samuel A Morton

No abstract provided.

Case-Based Reasoning In Fixture Design, David Brown, Iain Boyle, Kevin Rong

David C. Brown

Fixtures are designed to accurately locate and secure a part during machining operations such that the part can be manufactured to design specifications. To reduce the design costs associated with fixturing, various computer-aided fixture design (CAFD) methods have been developed through the years to assist the fixture designer. One approach is to use a case-based reasoning (CBR) approach where relevant design experience is retrieved from a design library, and adapted to provide a new fixture design solution. Indexing design cases is a critical issue in any CBR approach, and CBR systems can suffer from an inability to distinguish between cases …

Spectral Representation Of The Electrical Properties Of Layered Materials., Anthony Day, A. Mcgurn, D. Bergman, M. Thorpe

Anthony Roy Day

We present a spectral representation for the effective conductivity of two homogeneous layers joined at a rough interface. This spectral representation is closely related to the Bergman-Milton spectral representation for bulk composites, and is easily extended to multilayered materials. By comparing the layered system to a reference layered system that has a flat interface, we form a surface spectral density that captures all the effects of surface structure on the effective conductivity of the layered sample, and is independent of the conductivities of the two layers. Because of the anisotropy of the layered system there are two surface spectral densities, …

Enhanced Removal Of Oils From Surfaces: The Effect Of Ionic Strength On Cleaning, A. Davis, Samuel Morton, R. Counce, D. Depaoli, M. Hu

Samuel A Morton

No abstract provided.

Comparison Between Analytical Probabilistic And Computer Simulation Models, Using Current Design Examples, Barry A. Palynchuk Phd

Barry A. Palynchuk PhD

Closed form analytical expressions have been developed to solve several basic problems related to the hydrologic design of storm water management facilities. The collection of these analytical expressions is referred to as the Analytical Probabilistic Storm Water Models (APSWM). APSWM can be used as an alternative to the design storm simulation models in the design and analysis of storm water management facilities. In this paper, a comparison is made between APSWM and design storm simulation models as applied to an actual design case. Conventional outputs such as runoff volume, peak discharge, and peak discharge from detention ponds are reviewed and …

Effect Of Parallel Velocity Shear On The Electrostatic Ion-Cyclotron Instability In Flamentary Current Channels, Erick Agrimson, Su-Hyun Kim, Nicola D'Angelo, Robert L. Merlino

Erick Agrimson

No abstract provided.

Curvature-Induced Defect Unbinding In Toroidal Geometries, Mark Bowick, David R. Nelson, Alex Travesset

Physics - All Scholarship

Toroidal templates such as vesicles with hexatic bond orientational order are discussed. The total energy including disclination charges is explicitly computed for hexatic order embedded in a toroidal geometry. Related results apply for tilt or nematic order on the torus in the one Frank constant approximation. Although there is no topological necessity for defects in the ground state, we find that excess disclination defects are nevertheless energetically favored for fat torii or moderate vesicle sizes. Some experimental consequences are discussed.

Estuarine Water Quality Monitoring Network Quarterly Report (C-15397), Joseph N. Boyer

SERC Research Reports

No abstract provided.

Ua66/1/5 Applied Research & Technology Program Newsletter, Issue 1, Wku Applied Research & Technology Program

WKU Archives Records

Newsletter created by and about the Applied Research & Technology Program.

Invertibility Of Current Density From Near-Field Electromagnetic Data, Evangelos A. Coutsias, Daniel Sheltraw

Branch Mathematics and Statistics Faculty and Staff Publications

The problem of determining a current density confined to a volume from measurements of the magnetic and electric fields it produces exterior to that volume is known to have nonunique solutions. Despite the nonuniqueness of the inversion we show that one may nevertheless uniquely determine certain moments of the vector spherical harmonic expansion of the current. It is demonstrated that the determination of these moments allows for the unique inversion of a current density confined to a spherical shell. Although unique the inversion may be ill conditioned and require a regularization of the inversion as demonstrated in an example numerical …

Organic Coatings On Sedimentary Mineral Grains, Lawrence M. Mayer

University of Maine Office of Research Administration: Grant Reports

A pore protection hypothesis will be tested, provide a mechanistic basis for the observed patterns of organic carbon. Relationships between organic matter and mineral surfaces will be developed by: (1) Assessing the extent of organic matter coverage on mineral grains. Is organic carbon localized in small areas or is it widely dispersed? Wide dispersal implies that major fraction must reside in small pores. This question will be tested by completing development of a promising new method based on the of gas adsorption onto mineral surfaces. Completion work will focus on the nature of naked mineral surfaces, identifying variations that derive …

Equivalent Kernels Of Smoothing Splines In Nonparametric Regression For Clustered/Longitudinal Data, Xihong Lin, Naisyin Wang, Alan H. Welsh, Raymond J. Carroll

The University of Michigan Department of Biostatistics Working Paper Series

We compare spline and kernel methods for clustered/longitudinal data. For independent data, it is well known that kernel methods and spline methods are essentially asymptotically equivalent (Silverman, 1984). However, the recent work of Welsh, et al. (2002) shows that the same is not true for clustered/longitudinal data. First, conventional kernel methods fail to account for the within- cluster correlation, while spline methods are able to account for this correlation. Second, kernel methods and spline methods were found to have different local behavior, with conventional kernels being local and splines being non-local. To resolve these differences, we show that a smoothing …

Histospline Method In Nonparametric Regression Models With Application To Clustered/Longitudinal Data, Raymond J. Carroll, Peter Hall, Tatiyana V. Apanasovich, Xihong Lin

The University of Michigan Department of Biostatistics Working Paper Series

Kernel and smoothing methods for nonparametric function and curve estimation have been particularly successful in "standard" settings, where function values are observed subject to independent errors. However, when aspects of the function are known parametrically, or where the sampling scheme has significant structure, it can be quite difficult to adapt standard methods in such a way that they retain good statistical performance and continue to enjoy easy computability and good numerical properties. In particular, when using local linear modeling it is often awkward to both respect the sampling scheme and produce an estimator with good variance properties, without resorting to …

Stochastic Models Based On Molecular Hybridization Theory For Short Oligonucleotide Microarrays, Zhijin Wu, Richard Leblanc, Rafael A. Irizarry

Johns Hopkins University, Dept. of Biostatistics Working Papers

High density oligonucleotide expression arrays are a widely used tool for the measurement of gene expression on a large scale. Affymetrix GeneChip arrays appear to dominate this market. These arrays use short oligonucleotides to probe for genes in an RNA sample. Due to optical noise, non-specific hybridization, probe-specific effects, and measurement error, ad-hoc measures of expression, that summarize probe intensities, can lead to imprecise and inaccurate results. Various researchers have demonstrated that expression measures based on simple statistical models can provide great improvements over the ad-hoc procedure offered by Affymetrix. Recently, physical models based on molecular hybridization theory, have been …

Efficient Semiparametric Marginal Estimation For Longitudinal/Clustered Data, Naisyin Wang, Raymond J. Carroll, Xihong Lin

The University of Michigan Department of Biostatistics Working Paper Series

We consider marginal generalized semiparametric partially linear models for clustered data. Lin and Carroll (2001a) derived the semiparametric efficinet score funtion for this problem in the mulitvariate Gaussian case, but they were unable to contruct a semiparametric efficient estimator that actually achieved the semiparametric information bound. We propose such an estimator here and generalize the work to marginal generalized partially liner models. Asymptotic relative efficincies of the estimation or throughout are investigated. The finite sample performance of these estimators is evaluated through simulations and illustrated using a longtiudinal CD4 count data set. Both theoretical and numerical results indicate that properly …

Web Filtering Using Text Classification, R. Du, R. Safavi-Naini, Willy Susilo

Faculty of Informatics - Papers (Archive)

No abstract provided.

Resource Aware Information Dissemination In Ad Hoc Networks, Justin Lipman, P. Boustead, Joe F. Chicharo, J. Judge

Faculty of Informatics - Papers (Archive)

Information dissemination (flooding) forms an integral part of routing protocols, network management, service discovery and information collection (sensing). Given the broadcast nature of ad hoc network communications, information dissemination provides a challenging problem. This paper introduces Utility Based Flooding (UBF). UBF is a distributed optimised flooding mechanism for ad hoc networks that unlike existing optimised flooding algorithms is fully resource aware. Resource awareness is achieved by assigning a forwarding utility to neighouring nodes to determining the desirability of a neighbouring node in continuing a flood. UBF is particularly applicable to ad hoc network environments composed of heterogeneous nodes that may …

Provisioning Content Distribution Networks Over Shared Infrastructure, T. V. Nguyen, Chuntung Chou, P. Boustead

Faculty of Informatics - Papers (Archive)

The current paradigm of content distribution networks (CDN) deployment requires heavy infrastructure investment since a large number of servers have to be deployed over a wide area. To overcome this difficulty, we propose a new paradigm where future CDNs are to be deployed over a leased server infrastructure. This paradigm shift changes the object placement problem in current CDNs to a combined object placement and resource provisioning problem. In this paper, we present a formulation of this problem, which is a combinatorial optimization, and prove its NP-hardness. We also present a heuristic solution to this problem based on Lagrangian relaxation …

A Novel Dynamic Key Management Scheme For Secure Multicasting, J. Zhang, V. Varadharajan, Y. Mu

Faculty of Informatics - Papers (Archive)

We propose a new secure multicast scheme based on a novel hybrid key distribution scheme. This scheme meets the requirements described in the Internet Engineering Task Force (IETF) for multicast security architecture. It exhibits certain unique advantages in security services over existing schemes in the area of dynamic group key management. Our scheme allows efficient mechanisms for group members to join and leave a group frequently.

Securing Mobile Ip Enabled Laptop, Rungrat Wiangsripanawan, R. Safavi-Naini, Willy Susilo

Faculty of Informatics - Papers (Archive)

Mobile IP Onternet Protocol) enables access to the Internet anywhere with one IP address, hence, providing the flexibility that is required by today’s growing mobile work force. Deploying Mobile IP introduces new security h a t s that if not carefully addressed can have severe consequences for home organizations. IPSec is a commonly used protection mechanism that is employed in this context. IPSec requires a flexible key management scheme to provide cryptographic keys to communicating entities. A commonly used public key based key management system is SKIP (Simple Key-Management for Internet Protocols). In this paper we consider the scenario where …

Tcmca: A Source-Based Distributed Topology Control Algorithm For Mission Critical Applications In Mobile Ad-Hoc Networks, G. Srivastava, P. Boustead, Joe F. Chicharo, C. Ware

Faculty of Informatics - Papers (Archive)

Topology control in a wireless ad-hoc network allows better spatial reuse of the wireless channel and network resources. The existing topology control algorithms tend to optimise network power usage by keeping the topology connected but do not take the network application requirements into account. Mission critical applications which require explicit end-to-end bandwidth and delay guarantees may not find enough resources in the network with the existing network topology. We have devised a topology control algorithm for mission critical applications (TCMCA) in wireless ad-hoc networks, which adapts the network topology to improve the available resources for a set of mission critical …

Climatic Warming And Accompanying Changes In The Ecological Regime Of The Black Sea During 1990s, T Oguz, T Cokacar, P Malanotte-Rizzoli, Hw Ducklow

VIMS Articles

The Black Sea ecosystem is shown to experience abrupt shifts in its all trophic levels from primary producers to apex predators in 1995 - 1996. It arises as a manifestation of concurrent changes in its physical climate introduced by intensive warming of its surface waters as well as abrupt increases in the mean sea level and the net annual mean fresh water flux. The warming is evident in the annual-mean sea surface temperature (SST) data by a continuous rise at a rate of similar to 0.25 degreesC per year, following a strong cooling phase in 1991 - 1993. The most …

Mri: Acquisition Of A Modern Electron Microprobe At The University Of Maine, Charles V. Guidotti

University of Maine Office of Research Administration: Grant Reports

This award, made through the Major Research Instrumentation (MRI) Program, provides support for the acquisition of a state-of-the-art electron microprobe (EMP) for the microchemical characterization of geological materials. A new EMP will replace an aging (vintage 1981) ARL SEMQ in the Department of Geological Sciences at the University of Maine. The instrument will facilitate research on a range of topics in metamorphic petrology including, the speciation of Fe and distribution of OH- in metapelites, and light element (i.e. Li, B, Be) partitioning in granulite facies rocks. Research in paleoclimatology will also be enhanced by this instrument. The probe will be …

Task 32 Delayed Hydride Cracking Of Spent Fuel Cladding Under Repository Conditions, Ajit K. Roy, Anthony Hechanova, Amy J. Smiecinski

Publications (YM)

The objective of this quality-affecting task is to evaluate the susceptibility of spent nuclear fuel cladding materials (zirconium alloys) to stress corrosion cracking (SCC), delayed hydride cracking (DHC) and localized corrosion (pitting/crevice) in simulated repository environments. During the first year of this project, major efforts were focused on developing the infrastructure for performing the desired testing involving two highly corrosion-resistant alloys namely, zircaloy-2 (Zr-2) and zircaloy-4 (Zr-4) in simulated concentrated acidic water (SAW) and modified SAW (SAWM). Modification of the SAW chemistry was done by adding hydrochloric acid (HC1) to achieve lower pH. The construction of the "Materials Performance Laboratory …

Semantic Web In Action: Ontology-Driven Information Search, Integration And Analysis, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.