Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

160524 Full-Text Articles 190380 Authors 34362062 Downloads 342 Institutions

All Articles in Physical Sciences and Mathematics

Faceted Search

160524 full-text articles. Page 3895 of 4026.

Classical Phases And Quantum Angles In The Description Of Interfering Bose-Einstein Condensates, WJ Mullin, F Laloe 2010 University of Massachusetts - Amherst

Classical Phases And Quantum Angles In The Description Of Interfering Bose-Einstein Condensates, Wj Mullin, F Laloe

Physics Department Faculty Publication Series

The interference of two Bose-Einstein condensates, initially in Fock states, can be described in terms of their relative phase, treated as a random unknown variable. This phase can be understood either as emerging from the measurements or pre-existing to them; in the latter case, the originating states could be phase states with unknown phases, so an average over all their possible values is taken. Both points of view lead to a description of probabilities of results of experiments in terms of a phase angle, which plays the role of a classical variable. Nevertheless, in some situations, this description is not ...


Improving Farmers’ Perception And Use Of Climate Predictions In Farming Decisions: A Transition Model, Lisa M. PytlikZillig, Qi Hu, Kenneth G. Hubbard, Gary D. Lynne, Roger H. Bruning 2010 University of Nebraska-Lincoln

Improving Farmers’ Perception And Use Of Climate Predictions In Farming Decisions: A Transition Model, Lisa M. Pytlikzillig, Qi Hu, Kenneth G. Hubbard, Gary D. Lynne, Roger H. Bruning

Papers in Natural Resources

Despite tremendous efforts to improve weather and climate predictions and to inform farmers about the use of such weather products, farmers’ attitudes toward forecast use remain poor and farmer use of forecasts has not increased. This paper describes features of a new conceptual model for facilitating farmers’ use of weather products and offers preliminary evidence for its effectiveness based on a test-of-concept prototype. The prototype system provides farmers with contextualized information, the opportunity to use that information in relevant farming contexts, and collaborative interaction with other users. In addition, scaffolding and feedback are incorporated in the model to enhance learning ...


Semiclassical Complex-Time Method For Tunneling Ionization: Molecular Suppression And Orientational Dependence, Gordon A. Gallup, Ilya I. Fabrikant 2010 University of Nebraska-Lincoln

Semiclassical Complex-Time Method For Tunneling Ionization: Molecular Suppression And Orientational Dependence, Gordon A. Gallup, Ilya I. Fabrikant

Gordon Gallup Publications

We apply a previously developed semiclassical complex time method to the calculation of tunneling ionization of several diatomic molecules and CO2.We investigate the presence or absence of the molecular suppression effect by calculating ionization rates of N2 versus Ar, O2 versus Xe, F2 versus Ar, and CO versus Kr. Comparisons with other theories, including the molecular-orbital-Ammosov-Delone-Krainov (MO-ADK) model and the strong-field approximation, are given. We also analyze the dependence of the ionization rate on the angle θF between the molecular axis and the field direction. The theoretical results agree quite well with experiment for ...


Some Implications Of Chu's 10Ψ10 Generalization Of Bailey's 6Ψ6 Summation Formula, James McLaughlin, Andrew Sills 2010 West Chester University of Pennsylvania

Some Implications Of Chu's 10Ψ10 Generalization Of Bailey's 6Ψ6 Summation Formula, James Mclaughlin, Andrew Sills

Mathematics

Lucy Slater used Bailey's 6Ã6 summation formula to derive the Bailey pairs she used to construct her famous list of 130 identities of the Rogers-Ramanujan type.

In the present paper we apply the same techniques to Chu's 10Ã10 generalization of Bailey's formula to produce quite general Bailey pairs. Slater's Bailey pairs are then recovered as special limiting cases of these more general pairs.

In re-examining Slater's work, we find that her Bailey pairs are, for the most part, special cases of more general Bailey pairs containing one or more free parameters ...


A Novel Method For Solving Multiscale Elliptic Problems With Randomly Perturbed Data, Victor Ginting, A. Malqvist, M. Presho 2010 University of Wyoming

A Novel Method For Solving Multiscale Elliptic Problems With Randomly Perturbed Data, Victor Ginting, A. Malqvist, M. Presho

Mathematics Faculty Publications

We propose a method for efficient solution of elliptic problems with multiscale features and randomly perturbed coefficients. We use the multiscale finite element method (MsFEM) as a starting point and derive an algorithm for solving a large number of multiscale problems in parallel. The method is intended to be used within a Monte Carlo framework where solutions corresponding to samples of the randomly perturbed data need to be computed. We show that the proposed method converges to the MsFEM solution in the limit for each individual sample of the data. We also show that the complexity of the method is ...


Spatiotemporal Distributions Of Migratory Birds: Patchy Models With Delay, S. A. Gourley, Rongsong Liu, J. H. Wu 2010 University of Wyoming

Spatiotemporal Distributions Of Migratory Birds: Patchy Models With Delay, S. A. Gourley, Rongsong Liu, J. H. Wu

Mathematics Faculty Publications

We derive and analyze a mathematical model for the spatiotemporal distribution of a migratory bird species. The birds have specific sites for breeding and winter feeding, and usually several stopover sites along the migration route, and therefore a patch model is the natural choice. However, we also model the journeys of the birds along the flyways, and this is achieved using a continuous space model of reaction-advection type. In this way proper account is taken of flight times and in-flight mortalities which may vary from sector to sector, and this information is featured in the ordinary differential equations for the ...


An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. McFarlane, Charles Brewer-Carias 2010 Carleton University

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation ...


Local Versus Global Search In Channel Graphs, A.H. Hunter, Nicholas Pippenger 2010 University of Washington - Seattle Campus

Local Versus Global Search In Channel Graphs, A.H. Hunter, Nicholas Pippenger

All HMC Faculty Publications and Research

Previous studies of search in channel graphs has assumed that the search is global; that is, that the status of any link can be probed by the search algorithm at any time. We consider for the first time local search, for which only links to which an idle path from the source has already been established may be probed. We show that some well known channel graphs may require exponentially more probes, on the average, when search must be local than when it may be global.


Voting In Agreeable Societies, Deborah E. Berg '06, Serguei Norine, Francis E. Su, Robin Thomas, Paul Wollan 2010 Harvey Mudd College

Voting In Agreeable Societies, Deborah E. Berg '06, Serguei Norine, Francis E. Su, Robin Thomas, Paul Wollan

All HMC Faculty Publications and Research

No abstract provided in this article.


Two-Player Envy-Free Multi-Cake Division, John Cloutier '03, Kathryn L. Nyman, Francis E. Su 2010 Harvey Mudd College

Two-Player Envy-Free Multi-Cake Division, John Cloutier '03, Kathryn L. Nyman, Francis E. Su

All HMC Faculty Publications and Research

We introduce a generalized cake-cutting problem in which we seek to divide multiple cakes so that two players may get their most-preferred piece selections: a choice of one piece from each cake, allowing for the possibility of linked preferences over the cakes. For two players, we show that disjoint envy-free piece selections may not exist for two cakes cut into two pieces each, and they may not exist for three cakes cut into three pieces each. However, there do exist such divisions for two cakes cut into three pieces each, and for three cakes cut into four pieces each. The ...


Jane: A New Tool For The Cophylogeny Reconstruction Problem, Chris Conow, Daniel Fielder '11, Yaniv J. Ovadia '10, Ran Libeskind-Hadas 2010 California State Polytechnic University - Pomona

Jane: A New Tool For The Cophylogeny Reconstruction Problem, Chris Conow, Daniel Fielder '11, Yaniv J. Ovadia '10, Ran Libeskind-Hadas

All HMC Faculty Publications and Research

Background

This paper describes the theory and implementation of a new software tool, called Jane, for the study of historical associations. This problem arises in parasitology (associations of hosts and parasites), molecular systematics (associations of orderings and genes), and biogeography (associations of regions and orderings). The underlying problem is that of reconciling pairs of trees subject to biologically plausible events and costs associated with these events. Existing software tools for this problem have strengths and limitations, and the new Jane tool described here provides functionality that complements existing tools.

Results

The Jane software tool uses a polynomial time dynamic programming ...


Mathematical Biology At An Undergraduate Liberal Arts College, Stephen C. Adolph, Lisette G. de Pillis 2010 Harvey Mudd College

Mathematical Biology At An Undergraduate Liberal Arts College, Stephen C. Adolph, Lisette G. De Pillis

All HMC Faculty Publications and Research

Since 2002 we have offered an undergraduate major in Mathematical Biology at Harvey Mudd College. The major was developed and is administered jointly by the mathematics and biology faculty. In this paper we describe the major, courses, and faculty and student research and discuss some of the challenges and opportunities we have experienced.


Stability And Dynamics Of Self-Similarity In Evolution Equations, Andrew J. Bernoff, Thomas P. Witelski 2010 Harvey Mudd College

Stability And Dynamics Of Self-Similarity In Evolution Equations, Andrew J. Bernoff, Thomas P. Witelski

All HMC Faculty Publications and Research

A methodology for studying the linear stability of self-similar solutions is discussed. These fundamental ideas are illustrated on three prototype problems: a simple ODE with finite-time blow-up, a second-order semi-linear heat equation with infinite-time spreading solutions, and the fourth-order Sivashinsky equation with finite-time self-similar blow-up. These examples are used to show that self-similar dynamics can be studied using many of the ideas arising in the study of dynamical systems. In particular, the use of dimensional analysis to derive scaling invariant similarity variables is discussed, as well as the role of symmetries in the context of stability of self-similar dynamics. The ...


Direct Measurements Of Island Growth And Step-Edge Barriers In Colloidal Epitaxy, Rajesh Ganapathy, Mark R. Buckley, Sharon J. Gerbode, Itai Cohen 2010 Cornell University

Direct Measurements Of Island Growth And Step-Edge Barriers In Colloidal Epitaxy, Rajesh Ganapathy, Mark R. Buckley, Sharon J. Gerbode, Itai Cohen

All HMC Faculty Publications and Research

Epitaxial growth, a bottom-up self-assembly process for creating surface nano- and microstructures, has been extensively studied in the context of atoms. This process, however, is also a promising route to self-assembly of nanometer- and micrometer-scale particles into microstructures that have numerous technological applications. To determine whether atomic epitaxial growth laws are applicable to the epitaxy of larger particles with attractive interactions, we investigated the nucleation and growth dynamics of colloidal crystal films with single-particle resolution. We show quantitatively that colloidal epitaxy obeys the same two-dimensional island nucleation and growth laws that govern atomic epitaxy. However, we found that in colloidal ...


Recognizing Graph Theoretic Properties With Polynomial Ideals, Jesus A. De Loera, Christopher J. HIllar, Peter N. Malkin, Mohamed Omar 2010 University of California - Davis

Recognizing Graph Theoretic Properties With Polynomial Ideals, Jesus A. De Loera, Christopher J. Hillar, Peter N. Malkin, Mohamed Omar

All HMC Faculty Publications and Research

Many hard combinatorial problems can be modeled by a system of polynomial equations. N. Alon coined the term polynomial method to describe the use of nonlinear polynomials when solving combinatorial problems. We continue the exploration of the polynomial method and show how the algorithmic theory of polynomial ideals can be used to detect k-colorability, unique Hamiltonicity, and automorphism rigidity of graphs. Our techniques are diverse and involve Nullstellensatz certificates, linear algebra over finite fields, Gröbner bases, toric algebra, convex programming, and real algebraic geometry.


Judges' Awareness, Understanding, And Application Of Digital Evidence, Gary Craig Kessler 2010 Nova Southeastern University

Judges' Awareness, Understanding, And Application Of Digital Evidence, Gary Craig Kessler

CEC Theses and Dissertations

As digital evidence grows in both volume and importance in criminal and civil courts, judges need to fairly and justly evaluate the merits of the offered evidence. To do so, judges need a general understanding of the underlying technologies and applications from which digital evidence is derived. Due to the relative newness of the computer forensics field, there have been few studies on the use of digital forensic evidence and none about judges' relationship with digital evidence.

This study addressed judges' awareness, knowledge, and perceptions of digital evidence, using grounded theory methods. The interaction of judges with digital evidence has ...


The Topology Of Incidence Pseudographs, Thomas R. James, Reinhard Klette 2010 Otterbein University

The Topology Of Incidence Pseudographs, Thomas R. James, Reinhard Klette

Mathematics Faculty Scholarship

Incidence pseudographs model a (re°exive and symmetric) inci- dence relation between sets of various dimensions, contained in a count- able family. Work by Klaus Voss in 1993 suggested that this general discrete model allows to introduce a topology, and some authors have done some studies into this direction in the past (also using alternative discrete models such as, for example, abstract complexes or orders on sets of cells). This paper provides a comprehensive overview about the topology of incidence pseudographs. This topology has various appli- cations, such as in modeling basic data in 2D or 3D digital picture analysis ...


Expression, Purification, And Analysis Of Unknown Translation Factors From Escherichia Coli: A Synthesis Approach, Justin D. Walter, Peter Littlefield, Scott Delbecq, Gerry Prody, P. Clint Spiegel 2010 Western Washington University

Expression, Purification, And Analysis Of Unknown Translation Factors From Escherichia Coli: A Synthesis Approach, Justin D. Walter, Peter Littlefield, Scott Delbecq, Gerry Prody, P. Clint Spiegel

Chemistry

New approaches are currently being developed to expose biochemistry and molecular biology undergraduates to a more interactive learning environment. Here, we propose a unique project-based laboratory module, which incorporates exposure to biophysical chemistry approaches to address problems in protein chemistry. Each of the experiments described herein contributes to the stepwise process of isolating, identifying, and analyzing a protein involved in a central biological process, prokaryotic translation. Students are provided with expression plasmids that harbor an unknown translation factor, and it is their charge to complete a series of experiments that will allow them to develop hypotheses for discovering the identity ...


Rademacher-Type Formulas For Partitions And Overpartitions, Andrew Sills 2010 Georgia Southern University

Rademacher-Type Formulas For Partitions And Overpartitions, Andrew Sills

Mathematical Sciences Faculty Publications

A Rademacher-type convergent series formula which generalizes the Hardy-Ramanujan-Rademacher formula for the number of partitions of n and the Zuckerman formula for the Fourier coefficients of ϑ4_0 | τ_−1 is presented.


Quantum Algorithm Animator, Lori Eileen Nicholson 2010 Nova Southeastern University

Quantum Algorithm Animator, Lori Eileen Nicholson

CEC Theses and Dissertations

The design and development of quantum algorithms present a challenge, especially for inexperienced computer science students. Despite the numerous common concepts with classical computer science, quantum computation is still considered a branch of theoretical physics not commonly used by computer scientists. Experimental research into the development of a quantum computer makes the use of quantum mechanics in organizing computation more attractive, however the physical realization of a working quantum computer may still be decades away.

This study introduces quantum computing to computer science students using a quantum algorithm animator called QuAL. QuAL's design uses features common to classical algorithm ...


Digital Commons powered by bepress