Physical Sciences and Mathematics Commons^™

Three-Body Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Ahmad Hasan, Michael Schulz, Aaron C. Laforge, Jason S. Alexander, M. F. Ciappina, M. A. Khakoo, Kisra Nayomal Egodapitiya

Physics Faculty Research & Creative Works

Doubly differential cross sections for single ionization of atomic hydrogen by 75 keV proton impact have been measured and calculated as a function of the projectile scattering angle and energy loss. This pure three-body collision system represents a fundamental test case for the study of the reaction dynamics in few-body systems. A comparison between theory and experiment reveals that three-body dynamics is important at all scattering angles and that an accurate description of the role of the projectile-target-nucleus interaction remains a major challenge to theory.

Estimating Relative Abundance Of Young Of Year American Eel, Anguilla Rostrata, In The Virginia Tributaries Of Chesapeake Bay (Spring 2008), Troy D. Tuckey, Mary C. Fabrizio

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American eel in November 1999. The FMP focuses on increasing coastal states’ efforts to collect American eel data through both fishery-dependent and fishery-independent studies. Consequently, member jurisdictions agreed to implement an annual survey for young-of-year (YOY) American eels. The survey is intended to “…characterize trends in annual recruitment of the YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” (ASMFC 2000). The development of these surveys began in 2000 with full implementation …

Variational Theory Of Balance Systems, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

In this work we apply the Poincare-Cartan formalism of the Classical Field Theory to study the systems of balance equations (balance systems). We introduce the partial k-jet bundles of the configurational bundle and study their basic properties: partial Cartan structure, prolongation of vector fields, etc. A constitutive relation C of a balance system is realized as a mapping between a (partial) k-jet bundle and the extended dual bundle similar to the Legendre mapping of the Lagrangian Field Theory. Invariant (variational) form of the balance system corresponding to a constitutive relation C is studied. Special cases of balance systems -Lagrangian systems …

Fisheries Research Report No. 186 - A Preliminary Investigation Of The Potential Impacts Of The Proposed Kwinana Quay Development On The Commercially And Recreationally Important Fish And Crab Species In Cockburn Sound, C. Wakefield, Danielle Johnston, D C. Harris, Paul Lewis

Fisheries research reports

Prepared for Fremantle Ports

Cockburn Sound is the largest of the very few protected marine embayments along the lower west coast of Western Australia. It has been recognised as playing an integral role in the life history strategies of many marine species, including the highly valued snapper Pagrus auratus and blue swimmer crab Portunus pelagicus. Currently, the adult stocks of snapper in the West Coast Bioregion and blue swimmer crabs in Cockburn Sound are at depleted levels, most likely a result of high fishing pressure and below average recruitment in recent years for both species.

Due to increasing shipping operations …

Period-Doubling Bifurcation In An Array Of Coupled Stochastically-Excitable Elements Subjected To Global Periodic Forcing, Xiaohua Cui, Robert J. Rovetti, Ling Yang, Alan Garfinkel, James N. Weiss, Zhilin Qu

Mathematics, Statistics and Data Science Faculty Works

The collective behaviors of coupled, stochastically-excitable elements subjected to global periodic forcing are investigated numerically and analytically. We show that the whole system undergoes a period-doubling bifurcation as the driving period decreases, while the individual elements still exhibit random excitations. Using a mean-field representation, we show that this macroscopic bifurcation behavior is caused by interactions between the random excitation, the refractory period, and recruitment (spatial cooperativity) of the excitable elements.

Section Abstracts: Chemistry

Virginia Journal of Science

Abstracts of the Chemistry Section for the 87th Annual Meeting of the Virginia Academy of Science, May 27-29, 2009, Virginia Commonwealth University, Richmond Virginia.

Atomistic Modeling Of Amorphous Silicon Carbide: An Approximate First-Principles Study In Constrained Solution Space, Raymond Atta-Fynn, Parthapratim Biswas

Faculty Publications

Localized basis ab initio molecular dynamics simulation within the density functional framework has been used to generate realistic configurations of amorphous silicon carbide (a-SiC). Our approach consists of constructing a set of smart initial configurations that conform to essential geometrical and structural aspects of the materials obtained from experimental data, which is subsequently driven via a first-principles force field to obtain the best solution in a reduced solution space. A combination of a priori information (primarily structural and topological) along with the ab initio optimization of the total energy makes it possible to model a large system size (1000 atoms) …

Correlated Response In A Driven Flow Of Self-Organizing Particles Around A Slit In Porous Media By Interacting Lattice Gas, Ras B. Pandey, J.F. Gettrust

Faculty Publications

The flow of immiscible particles (A, B) through a porous medium with a vertical slit is studied by an interacting lattice-gas computer simulation on a discrete lattice. The source of the particles is connected to the bottom and particles are driven upward by concentration gradient and a pressure bias against gravity. Distribution of flowing particles around the slit is examined as a function of the slit width and bias at high and low porosity at a steady state. At the low bias, a sharp change in the densities (high in slit to low in adjacent porous media) of both constituents …

Fall 2009 Nova Southeastern University Undergraduate Student Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.

Strain Rate Patterns From Dense Gps Networks, Matthias Hackl, Rocco Malservisi, Shimon Wdowinski

School of Geosciences Faculty and Staff Publications

The knowledge of the crustal strain rate tensor provides a description of geodynamic processes such as fault strain accumulation, which is an important parameter for seismic hazard assessment, as well as anthropogenic deformation. In the past two decades, the number of observations and the accuracy of satellite based geodetic measurements like GPS greatly increased, providing measured values of displacements and velocities of points. Here we present a method to obtain the full continuous strain rate tensor from dense GPS networks. The tensorial analysis provides different aspects of deformation, such as the maximum shear strain rate, including its direction, and the …

Options For Achieving And Maintaining Low Salinity In Agricultural Dams, Tilwin Westrup

Resource management technical reports

No abstract provided.

Holism And Human History, Martin Zwick

Systems Science Faculty Publications and Presentations

We want and need the ‘whole story,’ but the whole story is difficult to tell. We can reduce the magnitude of the task by taking a cue from the title of the meeting, namely “Cosmos, Nature, Culture: A Transdisciplinary Conference.” The ‘whole story’ can be divided into three stories: the story of the unfolding of the universe (‘cosmos’), the story of the evolution of life (‘nature’), and the story of human history (‘culture’). This paper focuses on the third of these. Of course, human history is rooted in nature which is a manifestation of cosmos on our planet, but its …

Verification Of Population Ring Protocols In Pat, Yang Liu, Jun Pang, Jun Sun, Jianhua Zhao

Research Collection School Of Computing and Information Systems

The population protocol model has emerged as an elegant paradigm for describing mobile ad hoc networks, consisting of a number of nodes that interact with each other to carry out a computation. One essential property of self-stabilizing population protocols is that all nodes must eventually converge to the correct output value, with respect to all possible initial configurations. It has been shown that fairness constraints play a crucial role in designing population protocols. The Process Analysis Toolkit (PAT) has been developed to perform verifications under different fairness constraints efficiently. In particular, it can handle global fairness, which is required for …

Leak-Free Mediated Group Signatures, Xuhua Ding, Gene Tsudik, Shouhuai Xu

Research Collection School Of Computing and Information Systems

Group signatures are a useful cryptographic construct for privacy-preserving non-repudiable authentication, and there have been many group signature schemes. In this paper, we introduce a variant of group signatures that offers two new security properties called leak-freedom and immediate-revocation. Intuitively, the former ensures that an insider (i.e., an authorized but malicious signer) be unable to convince an outsider (e.g., a signature receiver) that she indeed signed a certain message; whereas the latter ensures that the authorization for a user to issue group signatures can be immediately revoked whenever the need arises (temporarily or permanently). These properties are not offered in …

Identifying Bug Signatures Using Discriminative Graph Mining, Hong Cheng, David Lo, Yang Zhou, Xiaoyin Wang, Xifeng Yan

Research Collection School Of Computing and Information Systems

Bug localization has attracted a lot of attention recently. Most existing methods focus on pinpointing a single statement or function call which is very likely to contain bugs. Although such methods could be very accurate, it is usually very hard for developers to understand the context of the bug, given each bug location in isolation. In this study, we propose to model software executions with graphs at two levels of granularity: methods and basic blocks. An individual node represents a method or basic block and an edge represents a method call, method return or transition (at the method or basic …

Continuous Obstructed Nearest Neighbor Queries In Spatial Databases, Yunjun Gao, Baihua Zheng

Research Collection School Of Computing and Information Systems

In this paper, we study a novel form of continuous nearest neighbor queries in the presence of obstacles, namely continuous obstructed nearest neighbor (CONN) search. It considers the impact of obstacles on the distance between objects, which is ignored by most of spatial queries. Given a data set P, an obstacle set O, and a query line segment q in a two-dimensional space, a CONN query retrieves the nearest neighbor of each point on q according to the obstructed distance, i.e., the shortest path between them without crossing any obstacle. We formulate CONN search, analyze its unique properties, and develop …

Compositemap: A Novel Framework For Music Similarity Measure, Bingjun Zhang, Jialie Shen, Qiaoliang Xiang, Ye Wang

Research Collection School Of Computing and Information Systems

With the continuing advances in data storage and communication technology, there has been an explosive growth of music information from different application domains. As an effective technique for organizing, browsing, and searching large data collections, music information retrieval is attracting more and more attention. How to measure and model the similarity between different music items is one of the most fundamental yet challenging research problems. In this paper, we introduce a novel framework based on a multimodal and adaptive similarity measure for various applications. Distinguished from previous approaches, our system can effectively combine music properties from different aspects into a …

Automatic Steering Of Behavioral Model Inference, David Lo, Leonardo Mariani, Mauro Pezze

Research Collection School Of Computing and Information Systems

Many testing and analysis techniques use finite state models to validate and verify the quality of software systems. Since the specification of such models is complex and time-consuming, researchers defined several techniques to extract finite state models from code and traces. Automatically generating models requires much less effort than designing them, and thus eases the verification and validation of large software systems. However, when models are inferred automatically, the precision of the mining process is critical. Behavioral models mined with imprecise processes can include many spurious behaviors, and can thus compromise the results of testing and analysis techniques that use …

Ktr: An Efficient Key Management Scheme For Secure Data Access Control In Wireless Broadcast Services Recovery, Qijun Gu, Peng Liu, Wang-Chien Lee, Chao-Hsien Chu

Research Collection School Of Computing and Information Systems

Wireless broadcast is an effective approach for disseminating data to a number of users. To provide secure access to data in wireless broadcast services, symmetric-key-based encryption is used to ensure that only users who own the valid keys can decrypt the data. With regard to various subscriptions, an efficient key management for distributing and changing keys is in great demand for access control in broadcast services. In this paper, we propose an efficient key management scheme, namely, key tree reuse (KTR), to handle key distribution with regard to complex subscription options and user activities. KTR has the following advantages. First, …

An Agent-Based Commodity Trading Simulation, Shih-Fen Cheng, Yee Pin Lim

Research Collection School Of Computing and Information Systems

In this paper, an event-centric commodity trading simulation powered by the multiagent framework is presented. The purpose of this simulation platform is for training novice traders. The simulation is progressed by announcing news events that affect various aspects of the commodity supply chain. Upon receiving these events, market agents that play the roles of producers, consumers, and speculators would adjust their views on the market and act accordingly. Their actions would be based on their roles and also their private information, and collectively they shape the market dynamics. This simulation has been effectively deployed for several training sessions. We will …

On The Effectiveness Of Software Diversity: A Systematic Study On Real-World Vulnerabilities, Jin Han, Debin Gao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Many systems have been introduced to detect software intrusions by comparing the outputs and behavior of diverse replicas when they are processing the same, potentially malicious, input. When these replicas are constructed using off-the-shelf software products, it is assumed that they are diverse and not compromised simultaneously under the same attack. In this paper, we analyze vulnerabilities published in 2007 to evaluate the extent to which this assumption is valid. We focus on vulnerabilities in application software, and show that the majority of these software products --- including those providing the same service (and therefore multiple software substitutes can be …

Bonus Plans Of Mice And Men, M. Thulasidas

Research Collection School Of Computing and Information Systems

Our best-laid plans often go awry. We see it all the time at a personal level -- accidents (both good and bad), deaths (both of loved ones and rich uncles), births, and lotteries all conspire to reshuffle our priorities and render our plans null and void. In fact, there is nothing like a solid misfortune to get us to put things in perspective. This opportunity may be the proverbial silver lining we are constantly advised to see. What is true at a personal level holds true also at a larger scale. The industry-wide financial meltdown has imparted a philosophical clarity …

Large-Scale Near-Duplicate Web Video Search: Challenge And Opportunity, Wan-Lei Zhao, Song Tan, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

The massive amount of near-duplicate and duplicate web videos has presented both challenge and opportunity to multimedia computing. On one hand, browsing videos on Internet becomes highly inefficient for the need to repeatedly fast-forward videos of similar content. On the other hand, the tremendous amount of somewhat duplicate content also makes some traditionally difficult vision tasks become simple and easy. For example, annotating pictures can be as simple as recycling the tags of Internet images retrieved from image search engines. Such tasks, of either to eliminate or to recycle near-duplicates, can usually be achieved by the nearest neighbor search of …

Characterization And Quantification Of Ground Heat Flux For Late Season Shallow Snow, Aurele Lamontagne

Boise State University Theses and Dissertations

Increasing populations, rapid land use changes, and climate change in mountainous areas have stressed water resources and reduced available water from snowpacks. In anticipation of warmer temperatures, receding snowlines, and increasing water demands, water managers will need detailed snowmelt energy and water balance information from the margin as transitional snow replaces deeper snowpacks. Patchy shallow snow, found at transitional snow elevations, has a distinct energy balance that includes local advection and short wave radiation penetration of snow less than 10 cm deep. Solar penetration to the soil surface provides a heat source that can be absorbed by the soil and …

Internal Structure And Geochronology Of The Gerrei Unit In The Flumendosa Area, Variscan External Nappe Zone, Sardinia, Italy, Ashley V. Dack

Boise State University Theses and Dissertations

To investigate the stratigraphy and structural evolution of the Variscan Orogen of the External Nappe Zone, Sardinia, Italy, field work and geochronologic analyses were combined to assess both regional and orogen scale issues. Geologic mapping, structural analysis, and sampling in the Flumendosa area coupled with high-precision U-Pb zircon geochronology were used to determine the duration of Ordovician magmatic activity and the structural evolution of the Variscan Orogen.

To constrain the duration of magmatism for the Flumendosa area, U-Pb ID/TIMS zircon analyses were performed on samples from a lower volcanic flow of the Ordovician Volcanic Unit and an upper, syn to …

Synthesis Completed Of Post-Fire Recovery Of Native Perennials In The Mojave, Sonoran Deserts, Scott R. Abella

Public Policy and Leadership Faculty Publications

Literature syntheses to develop status of knowledge reports are important to integrate and summarize the scattered scientific literature on a particular topic. The isolation and fragmentation of scientific literature on a topic is not necessarily a shortcoming of science. Rather, it is simply a consequence of having (1) research published in a diverse array of journals, (2) articles build on each other and therefore articles relevant to a particular topic can be published decades apart, and (3) funding virtually impossible to secure to do these periodic assessments of what we know and don’t know (competitive science grants want researchers to …

Compatibility Determination: Considerations For Siting Coastal And Ocean Uses (Draft), Jack Wiggin, Kristin Uiterwyk, Steve Bliven, Dan Hellin, Fara Courtney, Rich Delaney, Pat Hughes, Tracey Morin Dalton, Stephanie Moura, Nicholas Napoli, Kim Starbuck

Urban Harbors Institute Publications

This draft report is one of several prepared under contract to the Massachusetts Ocean Partnership (MOP) to support the Massachusetts Executive Office of Energy and Environmental Affairs (EEA) in its development of the integrated coastal ocean management plan mandated by the MA Oceans Act of 2008. Among other requirements, the Oceans Act states that the plan shall “identify appropriate locations and performance standards for activities, uses and facilities allowed under sections 15 and 16 of chapter 132A.” To fulfill this requirement, the EOEEA planning team wanted to utilize compatibility determinations as a tool for considering the appropriate locations for activities, …

On The Rigidity Of The Cotangent Complex At The Prime 2, James M. Turner

University Faculty Publications and Creative Works

In [D. Quillen, On the (co)homology of commutative rings, Proc. Symp. Pure Math. 17 (1970) 65-87; L. Avramov, Locally complete intersection homomorphisms and a conjecture of Quillen on the vanishing of cotangent homology, Annals of Math. 2 (150) (1999) 455-487] a conjecture was posed to the effect that if R → A is a homomorphism of Noetherian commutative rings then the flat dimension, as defined in the derived category of A-modules, of the associated cotangent complex LA / R satisfies: fdA LA / R < ∞ {long rightwards double arrow} fdA LA / R ≤ 2. The aim of this paper is to initiate an approach for solving this conjecture when R has characteristic 2 using simplicial algebra techniques. To that end, we obtain two results. First, we prove that the conjecture can be reframed in terms of certain nilpotence properties for the divided square γ2 and the André operation θ{symbol} as it acts on TorR (A, ℓ), ℓ any residue field of A. Second, we prove the conjecture is valid in two cases: when fdR A < ∞ and when R is a Cohen-Macaulay ring.

Freedom Of Choice As A Motivational Factor In Active Learning, Atanas Radenski

Mathematics, Physics, and Computer Science Faculty Articles and Research

Freedom to choose what, when, and how to contribute in a learning process can motivate students to actively engage and achieve more in their studies. However, freedom of choice complicates course management and may deter instructors from allowing such freedom. Our approach is to utilize existing functionality of course management systems such as Moodle to automatically facilitate and coordinate free student choices and provide much needed relief for instructors at the same time. Using Moodle we have developed novel digital study packs that blend freedom of choice with guidance and control. Our survey shows that assisted freedom of choice is …

Distributed Monitoring Of Conditional Entropy For Network Anomaly Detection, Chrisil Arackaparambil, Sergey Bratus, Joshua Brody, Anna Shubina

Computer Science Technical Reports

Monitoring the empirical Shannon entropy of a feature in a network packet stream has previously been shown to be useful in detecting anomalies in the network traffic. Entropy is an information-theoretic statistic that measures the variability of the feature under consideration. Anomalous activity in network traffic can be captured by detecting changes in this variability. There are several challenges, however, in monitoring this statistic. Computing the statistic efficiently is non-trivial. Further, when monitoring multiple features, the streaming algorithms proposed previously would likely fail to keep up with the ever-increasing channel bandwidth of network traffic streams. There is also the concern …