Scholar Press

ScholarPress is a suite of tools that will enable humanities scholars far more control of how they teach and present their research. We will develop three tools: Courseware, Researcher, and Vitaware. Courseware will allow instructors to easily publish course websites that incorporate digital resources and encourage critical analysis that is central to the humanities. Researcher will help humanities scholars collaborate by making it easy to aggregate and cite resources from various online collection services. Vitaware will provide scholars with a "live" feed of their traditional and digital scholarship. These tools will help manage digital identities-scholarly production that is visible online through course websites, blogs, and CVs-that are becoming more central to work in the humanities. In short, ScholarPress will lower the intimidating technical barrier for humanists to thoughtfully engage with new media and to facilitate digital discourse in the humanities

A pseudo-matched filter for chaos

A matched filter maximizes the signal-to-noise ratio of a signal. In the recent work of Corron et al. [Chaos 20, 023123 (2010)], a matched filter is derived for the chaotic waveforms produced by a piecewise-linear system. Motivated by these results, we describe a pseudo-matched filter, which removes noise from the same chaotic signal. It consists of a notch filter followed by a first-order, low-pass filter. We compare quantitatively the matched filter's performance to that of our pseudo-matched filter using correlation functions in a simulated radar application. On average, the pseudo-matched filter performs with a correlation signal-to-noise ratio that is 2.0 dB below that of the matched filter. Our pseudo-matched filter, though somewhat inferior in comparison to the matched filter, is easily realizable at high speed (> 1 GHz) for potential radar applications

On the Correlation Between the Spin-Independent and Spin-Dependent Direct Detection of Dark Matter

We study the correlation between spin-independent and spin-dependent scattering in the context of MSSM neutralino dark matter for both thermal and non-thermal histories. We explore the generality of this relationship with reference to other models. We discuss why either fine-tuning or numerical coincidences are necessary for the correlation to break down. We derive upper bounds on spin-dependent scattering mediated by a Z boson.Comment: 31 pages, 6 figures, 3 appendices; v2: refs added, minor typos corrected, journal versio

Dueling For Their Votes: A Study on the Impact of Presidential Debate Rhetoric on Public Opinion

The debates are key events for presidential candidates to influence public support for their policies. This study examines the impact of rhetorical strategies during presidential debates on public perceptions of unpopular issue stances. Using generic criticism, I examined the first two 2012 debates between Barack Obama and Mitt Romney and uncovered four rhetorical strategies used by the candidates: issue framing, appeals to authority, use of rebuttals, and appealing to liberal and conservative presumptions. I then tested an example of issue framing from each candidate to determine its effectiveness in persuading public opinion on unpopular issue stances. My results showed that Obama’s use of the strategy lowered the favorability of Romney’s proposed economic policies, while Romney’s use of it showed no significant relationship. Overall, the study provides a clearer picture of how politicians use rhetorical strategies during presidential debates in order to gain public support in areas where they are weak

Ultra-high-frequency piecewise-linear chaos using delayed feedback loops

We report on an ultra-high-frequency (> 1 GHz), piecewise-linear chaotic system designed from low-cost, commercially available electronic components. The system is composed of two electronic time-delayed feedback loops: A primary analog loop with a variable gain that produces multi-mode oscillations centered around 2 GHz and a secondary loop that switches the variable gain between two different values by means of a digital-like signal. We demonstrate experimentally and numerically that such an approach allows for the simultaneous generation of analog and digital chaos, where the digital chaos can be used to partition the system's attractor, forming the foundation for a symbolic dynamics with potential applications in noise-resilient communications and radar

Subwavelength position sensing using nonlinear feedback and wave chaos

We demonstrate a position-sensing technique that relies on the inherent sensitivity of chaos, where we illuminate a subwavelength object with a complex structured radio-frequency field generated using wave chaos and a nonlinear feedback loop. We operate the system in a quasi-periodic state and analyze changes in the frequency content of the scalar voltage signal in the feedback loop. This allows us to extract the object's position with a one-dimensional resolution of ~\lambda/10,000 and a two-dimensional resolution of ~\lambda/300, where \lambda\ is the shortest wavelength of the illuminating source.Comment: 4 pages, 4 figure

Asymmetric Dark Matter from a GeV Hidden Sector

Asymmetric Dark Matter (ADM) models relate the dark matter density to the baryon asymmetry, so that a natural mass scale for ADM is around a few GeV. In existing models of ADM, this mass scale is unexplained; here we generate this GeV scale for dark matter (DM) from the weak scale via gauge kinetic mixing with a new Abelian dark force. In addition, this dark sector provides an efficient mechanism for suppressing the symmetric abundance of DM through annihilations to the dark photon. We augment this sector with a higher dimensional operator responsible for communicating the baryon asymmetry to the dark sector. Our framework also provides DM candidate for gauge mediation models. It results in a direct detection cross section of interest for current experiments: sigma less than or similar to 10^{-42} cm^2 for DM masses in the range 1 - 15 GeV.Comment: 21 pages, 4 figure