Physical Sciences and Mathematics Commons^™

The Management Of Recreational Fisheries, Daryl Mcphee

Daryl McPhee

Coastal fisheries are complex ecological and social systems. In many countries, including Australia, they have evolved over time with a shift in focus from the commercial to the recreational sector. Recreational fishing can be defined as any fishing for which the primary motivation is leisure rather than profit, and for which harvested animals do not constitute an individual’s primary resource for nutritional needs. It is an ubiquitous activity in marine and freshwater regions of Australia, with most recreational fishing activity occurring in estuarine, coastal and shallow reef areas. The dominant form of recreational fishing is line fishing (angling), although it …

Momentum Returns To S&P/Asx 100 Constituents, Bruce Vanstone, Tobias Hahn, Gavin Finnie

Bruce Vanstone

No abstract provided.

Storm-Induced Inner-Continental Shelf Circulation And Sediment Transport: Long Bay, South Carolina, John Warner, Charlene Silvester, Brandy Armstrong, George Voulgaris, Timothy Nelson, William Schwab, Jane Denny

George Voulgaris

Long Bay is a sediment-starved, arcuate embayment located along the US East Coast connecting both South and North Carolina. In this region the rates and pathways of sediment transport are important because they determine the availability of sediments for beach nourishment, seafloor habitat, and navigation. The impact of storms on sediment transport magnitude and direction were investigated during the period October 2003–April 2004 using bottom mounted flow meters, acoustic backscatter sensors and rotary sonars deployed at eight sites offshore of Myrtle Beach, SC, to measure currents, water levels, surface waves, salinity, temperature, suspended sediment concentrations, and bedform morphology. Measurements identify …

Book Review Of Hacking: The Next Generation (Written By Nitesh Dhanjani, Billy Rios & Brett Hardin), Katina Michael

Professor Katina Michael

Hacking: The Next Generation demonstrates just how hackers continue to exploit “back doors”. New ways of working and new ways of communicating have meant that the number of attack vectors continue to rise rapidly. This provides hackers with a greater number of opportunities to penetrate systems using blended approaches while organizations struggle to come up to speed with the latest technology developments and commensurate security capabilities. Dealing with anticipated threats is a lot harder than dealing with known threats.

Self-Assembly Of Helical Ribbons, Yevgeniya V. Zastavker, Neer Asherie, Aleksey Lomakin, Jayanti Pande, Joanne M. Donovan, Joel M. Schnur, George B. Benedek

Yevgeniya V. Zastavker

The self-assembly of helical ribbons is examined in a variety of multicomponent enantiomerically pure systems that contain a bile salt or a nonionic detergent, a phosphatidylcholine or a fatty acid, and a steroid analog of cholesterol. In almost all systems, two different pitch types of helical ribbons are observed: high pitch, with a pitch angle of 54 ± 2°, and low pitch, with a pitch angle of 11 ± 2°. Although the majority of these helices are right-handed, a small proportion of left-handed helices is observed. Additionally, a third type of helical ribbon, with a pitch angle in the range …

Analysis Of Segmentation Algorithms For Pavement Distress Images, Allen Downey, Haris N. Koutsopoulos, Ibrahim El Sanhouri

Allen B. Downey

Collection and analysis of pavement distress data is an important component of any pavement‐management system. Various systems are currently under development that automate this process. They consist of appropriate hardware for the acquisition of pavement distress images and, in some cases, software for the analysis of the collected data. An important step in the automatic interpretation of images is segmentation, the process of extracting the objects of interest (distresses) from the background. We examine algorithms for segmenting pavement images and evaluate their effectiveness in separating the distresses from the background. The methods examined include the Otsu method, Kittler's method, a …

Primitive-Based Classification Of Pavement Cracking Images, Allen Downey

Allen B. Downey

Collection and analysis of pavement distress data are receiving attention for their potential to improve the quality of information on pavement condition. We present an approach for the automated classificaton of asphalt pavement distresses recorded on video or photographic film. Based on a model that describes the statistical properties of pavement images, we develop algorithms for image enhancement, segmentation, and distress classification. Image enhancement is based on subtraction of an “average” background: segmentation assigns one of four possible values to pixels based on their likelihood of belonging to the object. The classification approach proceeds in two steps: in the first …

Converging And Coexisting Systems Towards Smart Surveillance, Katina Michael, Mg Michael

Professor Katina Michael

Tracking and monitoring people as they operate within their personal networks benefits service providers and their constituents but involves hidden risks and costs.

Automatic identification technologies, CCTV cameras, pervasive and mobile networks, wearable computing, location-based services and social networks have traditionally served distinct purposes. However, we have observed patterns of integration, convergence and coexistence among all these innovations within the information and communication technology industry.1For example, ‘location-based social networking’ can draw on a smart phone's capacity to identify a user uniquely, locate him within 1–2m and share this information across his social network in real time. The resulting ability to …

Biodiversity Is A Whitefella Word: Changing Relationships Between Aboriginal People And The Nsw National Parks And Wildlife Service, Michael Adams, Anthony English

Michael Adams

No abstract provided.

Mitigation Of Co2 From A Coal-Fired Power Plant Using Microalgae: Development And Demonstration, Samuel Morton, R. Andrews, M. Crocker, C. Crofcheck, J. Groppo, A. Placido, A. Shea, M. Wilson

Samuel A Morton

No abstract provided.

Ultrashort Pulse Propagation And Multi-Chromatic Ionization In Dielectrics, Jeremy Gulley

Jeremy R. Gulley

No abstract is currently available.

Acting As If Tomorrow Matters: Accelerating The Transition To Sustainability, John Dernbach

John C. Dernbach

No abstract provided.

Editorial: The Idio-Technopolis, Katina Michael

Professor Katina Michael

The rapid rise of social media has brought with it an emphasis on the distinct dimensions of the whole person. Social media recognises that the individual has a personal network of extensions- a home life, a work life, a social life, a study life, a hobbyist life, and much more- some of these identities even hidden from full view. Each of these online value networks are now accessible by big business, where opinion leaders and early adopters are easily distinguishable, and where brand commentary between consumers matters manifold more than any form of targeted advertising.

Why Match In Individually And Cluster Randomized Trials?, Laura Balzer, Maya Petersen, Mark Van Der Laan

Laura B. Balzer

The decision to match individuals or clusters in randomized trials is motivated by both practical and statistical concerns. Matching protects against chance imbalances in baseline covariate distributions and is thereby thought to improve study credibility. Matching is also implemented to increase study power. Analogue to Rose and van der Laan (2009), this article investigates the asymptotic efficiency of pair-matching individuals or clusters relative to not matching in randomized trials. We focus on estimating the average treatment effect. We use the efficient influence curve to understand the information provided by each design for estimation of the target causal parameter. Our approach …

Viscosity Measurements On Colloidal Dispersions (Nanofluids) For Heat Transfer Applications, Jessica Townsend, Rebecca J. Christianson, D Venerus, J Buongiorno, M A. Kedzierski, Et Al.

Rebecca J. Christianson

This article reports viscosity data on a series of colloidal dispersions collected as part of the International Nanofluid Property Benchmark Exercise (INPBE). Data are reported for seven different fluids that include dispersions of metal-oxide nanoparticles in water, and in synthetic oil. These fluids, which are also referred to as nanofluids, are currently being researched for their potential to function as heat transfer fluids. In a recently published paper from the INPBE study, thermal conductivity data from more than 30 laboratories around the world were reported and analyzed. Here, we examine the influence of particle shape and concentration on the viscosity …

Viscosity Measurements On Colloidal Dispersions (Nanofluids) For Heat Transfer Applications, Jessica Townsend, Rebecca J. Christianson, D Venerus, J Buongiorno, M A. Kedzierski, Et Al.

Jessica Townsend

This article reports viscosity data on a series of colloidal dispersions collected as part of the International Nanofluid Property Benchmark Exercise (INPBE). Data are reported for seven different fluids that include dispersions of metal-oxide nanoparticles in water, and in synthetic oil. These fluids, which are also referred to as nanofluids, are currently being researched for their potential to function as heat transfer fluids. In a recently published paper from the INPBE study, thermal conductivity data from more than 30 laboratories around the world were reported and analyzed. Here, we examine the influence of particle shape and concentration on the viscosity …

Mathematics Colloquium: Inverse Problems And Uncertainty Quantification, Jodi Mead

Jodi Mead

Combining physical or mathematical models with observational data often results in an ill-posed inverse problem. Regularization is typically used to solve ill-posed problems, and it can be viewed as adding statistical or probability information to the problem in the form of uncertainties. These uncertainties occur in the model, parameters or measurements and quantifying them is a challenge. The Bayesian interpretation of uncertainties formalizes the process of updating prior beliefs with observational data, however, it can be computationally demanding. Alternatively, we develop one of the simplest forms of regularization, least squares, to estimate prior uncertainty and call it the chi-squared method. …

Variances For Maximum Penalized Likelihood Estimates Obtained Via The Em Algorithm, Mark Segal, Peter Bacchetti, Nicholas Jewell

Mark R Segal

We address the problem of providing variances for parameter estimates obtained under a penalized likelihood formulation through use of the EM algorithm. The proposed solution represents a synthesis of two existent techniques. Firstly, we exploit the supplemented EM algorithm developed in Meng and Rubin (1991) that provides variance estimates for maximum likelihood estimates obtained via the EM algorithm. Their procedure relies on evaluating the Jacobian of the mapping induced by the EM algorithm. Secondly, we utilize a result from Green (1990) that provides an expression for the Jacobian of the mapping induced by the EM algorithm applied to a penalized …

Backcalculation Of Hiv Infection Rates, Peter Bacchetti, Mark Segal, Nicholas Jewell

Mark R Segal

Backcalculation is an important method of reconstructing past rates of human immunodeficiency virus (HIV) infection and for estimating current prevalence of HIV infection and future incidence of acquired immunodeficiency syndrome (AIDS). This paper reviews the backcalculation techniques, focusing on the key assumptions of the method, including the necessary information regarding incubation, reporting delay, and models for the infection curve. A summary is given of the extent to which the appropriate external information is available and whether checks of the relevant assumptions are possible through use of data on AIDS incidence from surveillance systems. A likelihood approach to backcalculation is described …

An Annotated Bibliography Of Methods For Analyzing Correlated Categorical Data, Mark Ashby, John Neuhaus, Walter Hauck, Peter Bacchetti, David Heilbron, Nicholas Jewell, Mark Segal, Robert Fusaro

Mark R Segal

This paper provides an annotated bibliography of over 100 articles concerning methods for analyzing correlated categorical response data. Most of the papers listed here concern categorical regression models and estimation, with particular emphasis on binary responses. The papers are classified by several characteristics which group them according to common themes. The bibliography serves as a reference of methods for analysts of correlated categorical data, as well as for persons interested in methodologic work in this active area of statistical research.

Managing Knowledge For The Development Of The Mekong Delta., Hans-Dieter Evers, Solvay Gerke

Solvay Gerke

No abstract provided.

Nonlinear Ultrashort Pulse Propagation And Multi-Chromatic Ionization In Bulk Dielectrics, Jeremy Gulley

Jeremy R. Gulley

No abstract is currently available.

Performance Enhancement In Organic Solar Cells Using A Grating Electrode, Hoi Lam Tam, Qingyi Yang, Gui Xin Li, F.R. Zhu

Professor ZHU, Fu Rong

Light trapping is a promising approach, e.g., by scattering the incident light to oblique angle to increase the dwell time of the light inside the devices, to improve light absorption in the active layer in organic solar cells (OSCs). In this work, the absorption enhancement in OSCs is realized using a poly(methyl methacrylate) (PMMA)/indium-tin-oxide (ITO) grating electrode. Photovoltaic properties such as external quantum efficiency and power conversion efficiency of a set of structural identical OSCs made with a planar ITO anode (control device) and a PMMA/ITO grating electrode were analyzed. The grating incorporated OSCs resulted in a ~10% increase in …

A Workable Moral Strategy For Achieving And Preserving World Peace: A Strategy That Can Create Over 500,000 American Jobs, Raymond Wilson

Raymond Wilson

Nspiring Activities For College Algebra In Context, Lisa Yocco

Lisa S. Yocco

Use the new features of the TI-Nspire to analyze, solve, and interpret real-life problems. Activities such as using background images to model and transform functions in a real-world context, using sliders to investigate functions, and changing the parameters of a linear programming problem will be explored.

Microwave Optics Research, Allen Andersen, Todd Lines

Allen Andersen

The BYU-Idaho Physics Department x-band microwave optics equipment was originally intended for use in classroom demonstrations. I evaluated this equipment for use in research. I designed and built additional equipment needed in order to perform attenuation and other experiments then used it to conduct research on the transmission properties of paper and other substances. The new equipment allowed me to create a standard experimental procedure, take reasonably accurate measurements, and reduce undesired standing wave effects. Mathematical and experimental analysis was done to determine the necessary parameters of the new equipment. The new apparatus is comparable to setups featured in published …

Optimal Upstream Collocation Solution Of The One-Dimensional Steady-State Convection-Diffusion Equation, Stephen Brill

Stephen H. Brill

We give herein analytical formulas for the solution of the Hermite collocation discretization of the unforced steady-state convection-diffusion equation in one spatial dimension and with constant coefficients, defined on a uniform mesh, with Dirichlet boundary conditions. The accuracy of the method is advanced by employing "upstream weighting" of the convective term in an optimal way, avoiding both "smearing" and unwanted oscillations, particularly for large Péclet numbers. Computational examples illustrate the efficacy of using optimal upstream weighting.

Analytical Solution Of Hermite Collocation Discretization Of Self-Adjoint Ordinary Differential Equations, Stephen Brill

Stephen H. Brill

We give herein analytical formulas for the solutions of a class of boundary value problems (BVPs) discretized by Hermite collcation. Specifically, our ordinary differential equations (ODEs) are self-adjoint, homogeneous, and have constant coefficients. Both Dirichlet and Neumann boundary conditions are considered. Analysis is provided which compares the discrete collocation solultion to the continuous solution. Computational examples are given.

Analytical Solution Of Hermite Collocation Discretization Of The Steady-State Convection-Diffusion Equation, Stephen Brill

Stephen H. Brill

We give herein analytical formulas for the Hermite collocation solution of the steady-state convection-diffusion equation with constant coefficients defined on a uniform mesh in one spatial dimension. Both Dirichlet and Neumann boundary conditions are considered. Analysis is provided which compares the discrete collocation solution to the continuous solution. Unlike the solution obtained via the central difference discretization, the collocation solution is proven to be oscillation free, irrespective of the value of the Péclet number. For modest Péclet numbers, the collocation solution is shown to provide an excellent approximation to the solution of the continuous problem.

Optimal Collocation Solution Of The One-Dimensional Steady-State Convection-Diffusion Equation With Variable Coefficients, Stephen Brill

Stephen H. Brill

We study the Hermite collocation solution of the one-dimensional-steady-state convection-diffusion equation with Dirichlet boundary conditions. The diffusion coefficient is constant while the convection coefficient is piecewise contant. A uniform mesh is imposed on each portion of the domain on which the convection coefficient is constant, but each portion may have a different uniform mesh. Formulas are derived for the exact solution of the matrix equation that arises from the collocation discretization. These formulas possess free "upstreaming/downstreaming" parameters, the values of which may be chosen to yield numerical solutions of great accuracy.