# Physical Sciences and Mathematics Commons™

215,087 Full-Text Articles 270,776 Authors 47,230,550 Downloads 417 Institutions

## All Articles in Physical Sciences and Mathematics

215,087 full-text articles. Page 6040 of 6050.

Deriving An X-Ray Luminosity Function Of Dwarf Novae Based On Parallax Measurements, 2010 University of Leicester

#### Deriving An X-Ray Luminosity Function Of Dwarf Novae Based On Parallax Measurements, K. Byckling, K. Mukai, J. R. Thorstensen, J. P. Osborne

##### Open Dartmouth: Published works by Dartmouth faculty

We have derived an X-ray luminosity function using parallax-based distance measurements of a set of 12 dwarf novae, consisting of Suzaku, XMM-Newton and ASCA observations. The shape of the X-ray luminosity function obtained is the most accurate to date, and the luminosities of our sample are concentrated between ~10^{30}-10^{31} erg s^{-1}, lower than previous measurements of X-ray luminosity functions of dwarf novae. Based on the integrated X-ray luminosity function, the sample becomes more incomplete below ~3 x 10^{30} erg s^{-1} than it is above this luminosity limit, and the sample is dominated by X-ray ...

On The Reliability Of Wireless Fingerprinting Using Clock Skews, 2010 Dartmouth College

#### On The Reliability Of Wireless Fingerprinting Using Clock Skews, Chrisil Arackaparambil, Sergey Bratus, Anna Shubina, David Kotz

##### Open Dartmouth: Published works by Dartmouth faculty

Determining whether a client station should trust an access point is a known problem in wireless security. Traditional approaches to solving this problem resort to cryptography. But cryptographic exchange protocols are complex and therefore induce potential vulnerabilities in themselves. We show that measurement of clock skews of access points in an 802.11 network can be useful in this regard, since it provides fingerprints of the devices. Such fingerprints can be used to establish the first point of trust for client stations wishing to connect to an access point. Fingerprinting can also be used in the detection of fake access ...

A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, 2010 Claremont McKenna College; Pitzer College; Scripps College

#### A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, Donald A. Mcfarlane, Joyce Lundberg, Warren Roberts

##### WM Keck Science Faculty Papers

The oldest known spatially-explicit archaeological excavation, conducted in Brixham cave, Devon, in 1858, is reconstructed using geographic information systems technology. Two dimensional plots of individual fossil taxa and flint artefacts demonstrate the utility of the technique for elucidating taphonomy and palaeobiology. The cave served as a den for hibernating brown bears, as a den for hyena and cave lion, and as a reliquary for their prey.

An Amazing Mathematical Card Trick, 2010 Harvey Mudd College

#### An Amazing Mathematical Card Trick, Arthur T. Benjamin

##### All HMC Faculty Publications and Research

A magician gives a member of the audience 20 cards to shuffle. After the cards are thoroughly mixed, the magician goes through the deck two cards at a time, sometimes putting the two cards face to face, sometimes back to back, and sometimes in the same direction. Before dealing each pair of cards into a pile, he asks random members of the audience if the pair should be flipped over or not. He goes through the pile again four cards at a time and before each group of four is dealt to a pile, the audience gets to decide whether ...

Stability And Dynamics Of Self-Similarity In Evolution Equations, 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 ...

Voting In Agreeable Societies, 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

Two-Player Envy-Free Multi-Cake Division, 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 ...

A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, 2010 University of Maine

#### A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski

##### Open Dartmouth: Published works by Dartmouth faculty

Firn microstructure is accurately characterized using images obtained from scanning electron microscopy (SEM). Visibly etched grain boundaries within images are used to create a skeleton outline of the microstructure. A pixel-counting utility is applied to the outline to determine grain area. Firn grain sizes calculated using the technique described here are compared to those calculated using the techniques of Gow (1969) and Gay and Weiss (1999) on samples of the same material, and are found to be substantially smaller. The differences in grain size between the techniques are attributed to sampling deficiencies (e.g. the inclusion of pore filler in ...

Direct Measurements Of Island Growth And Step-Edge Barriers In Colloidal Epitaxy, 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, 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.

The Norm Of A Truncated Toeplitz Operator, 2010 Pomona College

#### The Norm Of A Truncated Toeplitz Operator, Stephan Ramon Garcia, William T. Ross

##### Pomona Faculty Publications and Research

We prove several lower bounds for the norm of a truncated Toeplitz operator and obtain a curious relationship between the H2 and Hnorms of functions in model spaces.

On Baryon Number Non-Conservation In Two-Dimensional O(2n+1) Qcd, 2010 Massachusetts Institute of Technology

#### On Baryon Number Non-Conservation In Two-Dimensional O(2n+1) Qcd, Tamar Friedmann

##### Mathematics and Statistics: Faculty Publications

We construct a classical dynamical system whose phase space is a certain infinite dimensional Grassmannian manifold, and propose that it is equivalent to the large N limit of two-dimensional QCD with an O(2N + 1) gauge group. In this theory, we find that baryon number is a topological quantity that is conserved only modulo 2. We also relate this theory to the master field approach to matrix models.

Some New Classes Of Complex Symmetric Operators, 2010 Pomona College

#### Some New Classes Of Complex Symmetric Operators, Stephan Ramon Garcia, Warren R. Wogen

##### Pomona Faculty Publications and Research

We say that an operator $T \in B(H)$ is complex symmetric if there exists a conjugate-linear, isometric involution $C:H\to H$ so that $T = CT^*C$. We prove that binormal operators, operators that are algebraic of degree two (including all idempotents), and large classes of rank-one perturbations of normal operators are complex symmetric. From an abstract viewpoint, these results explain why the compressed shift and Volterra integration operator are complex symmetric. Finally, we attempt to describe all complex symmetric partial isometries, obtaining the sharpest possible statement given only the data $(\dim \ker T, \dim \ker T^*)$.

Review: Nontangential Limits In Pt(Μ)-Spaces And The Index Of Invariant Subgroups, 2010 Pomona College

#### Review: Nontangential Limits In Pt(Μ)-Spaces And The Index Of Invariant Subgroups, Stephan Ramon Garcia

##### Pomona Faculty Publications and Research

No abstract provided.

Review: Common Cyclic Vectors For Unitary Operators, 2010 Pomona College

#### Review: Common Cyclic Vectors For Unitary Operators, Stephan Ramon Garcia

##### Pomona Faculty Publications and Research

No abstract provided.

Ditopic Dithiophosphonates And Their Related Rotaxanes, 2010 Eastern Illinois University

#### Ditopic Dithiophosphonates And Their Related Rotaxanes, Robert Ray Baum Jr.

##### Masters Theses

No abstract provided.

Assessing The Welfare Effects Of Us Biofuel Policies, 2010 Iowa State University

#### Assessing The Welfare Effects Of Us Biofuel Policies, Giancarlo Moschini, Harvey Lapan, Jingbo Cui, Joseph Cooper

##### Economics Publications

This article assesses the main welfare implications of US policies to support biofuels, with an emphasis on corn-based ethanol. The analysis relies on an open economy, multimarket equilibrium model that links world and domestic energy and agricultural markets and explicitly accounts for the externalities of carbon emissions. The first-best policy in our context entails a carbon tax (implemented with a tax on fuel and a subsidy for ethanol), an import tariff on oil, and an export tax on corn. Although this policy is likely not feasible, we show that a second- best policy with an optimally chosen fuel tax and ...

2010 Claremont McKenna College

#### Effective Environmental Management Of The National Park Service: A Case Study Of Channel Islands National Park, Daniel T. Olmsted

##### CMC Senior Theses

The topic of protected area management serves as the focal point of my thesis. The fundamental question I seek to answer is; what constitutes effective environmental management and how is it exemplified in the National Park Service (NPS)? How exactly does the NPS continually earn the trust and confidence of the American people when so many other government agencies are viewed in a negative light? How does the Channel Islands National Park, in particular, shape the economic and political framework in which it operates to achieve its goals? How does this agency effectively manage such a complex ecosystem spanning across ...

Sustaining Rural Economies With Wind Development, 2010 Claremont McKenna College

#### Sustaining Rural Economies With Wind Development, Eric J. Van Oss

##### CMC Senior Theses

This paper discusses the effects of wind development in rural areas. Areas of focus include: direct job creation, indirect job creation, tax revenue and government policies. The effects of state and federal renewable energy policies are discussed and well as the impacts to rural economies.

Analytical Chemistry 2.0, 2010 DePauw University

#### Analytical Chemistry 2.0, David Harvey

##### Chemistry & Biochemistry Faculty publications

No abstract provided.