The Bernstein Center of a p-adic Unipotent Group

Francois Rodier proved that it is possible to view smooth representations of certain totally disconnected abelian groups (the underlying additive group of a finite-dimensional p-adic vector space, for example) as sheaves on the Pontryagin dual group. For nonabelian totally disconnected groups, the appropriate dual space necessarily includes representations which are not one-dimensional, and does not carry a group structure. The general definition of the topology on the dual space is technically unwieldy, so we provide three different characterizations of this topology for a large class of totally disconnected groups (which includes, for example, p-adic unipotent groups), each with a somewhat different flavor. We then use these results to demonstrate some formal similarities between smooth representations and sheaves on the dual space, including a concrete description of the Bernstein center of the category of smooth representations

The effect of dynamic range compression on the psychoacoustic quality and loudness of commercial music

It is common practice for music productions to be mastered with the aim of increasing the perceived loudness for the listener, allowing one record to stand out from another by delivering an immediate impact and intensity. Since the advent of the Compact Disc in 1980, music has increased in RMS level by up to 20dB. This results in many commercial releases being compressed to a dynamic range of 2–3 dB. Initial findings of this study have determined that amplitude compression adversely affects the audio signal with the introduction of audible artifacts such as sudden gain changes, modulation of the noise floor and signal distortion, all of which appear to be related to the onset of listener fatigue. In this paper, the history and changes in trends with respect to dynamic range are discussed and findings will be presented and evaluated. Initial experimentation, and both the roadmap and challenges for further and wider research are also described and discussed. The key aim of this research is to quantify the effects (both positive and negative) of dynamic range manipulation on the audio signal and subsequent listener experience. A future goal of this study is to ultimately define recommended standards for the dynamic range levels of mastered music in a similar manner to those associated with the film industry

A resolution of singularities for Drinfeld's compactification by stable maps

Drinfeld's relative compactification plays a basic role in the theory of automorphic sheaves, and its singularities encode representation-theoretic information in the form of intersection cohomology. We introduce a resolution of singularities consisting of stable maps from nodal deformations of the curve into twisted flag varieties. As an application, we prove that the twisted intersection cohomology sheaf on Drinfeld's compactification is universally locally acyclic over the moduli stack of G-bundles at points sufficiently antidominant relative to their defect

Remote Vibration Estimation Using Displaced Phase Center Antenna SAR in a Strong Clutter Environment

Synthetic aperture radar (SAR) is a ubiquitous remote sensing platform that is used for numerous applications. In its most common con\ufb01guration, SAR produces a high resolution, two-dimensional image of a scene of interest. An underlying assumption when creating this high resolution image is that all targets in the ground scene are stationary throughout the duration of the image collection. If a target is not static, but instead vibrating, it introduces a modulation on the returned radar signal termed the micro-Doppler e\ufb00ect. The ability to estimate the targets vibration frequency and vibration amplitude by exploiting the micro-Doppler e\ufb00ect, all while in a high clutter environment can provide strategic information for target identi\ufb01cation and target condition/status. This thesis discusses one method that processes the non-stationary signal of interest generated by the vibrating target in displaced phase center antenna (DPCA)-SAR in high clutter. The method is based on the extended Kalman \ufb01lter (EKF) \ufb01rst proposed by Dr. Wang in his PhD dissertation titled Time-frequency Methods for Vibration Estimation Using Synthetic Aperture Radar [24]. Previously, EKF method could accurately estimate the target\u27s vibration frequency for single component sinusoidal vibrations. In addition, the target\u27s vibration amplitude and position could be tracked throughout the duration of the aperture for single component sinusoidal vibrations. This thesis presents a modi\ufb01cation to the EKF method, which improves the EKF method\u27s overall performance. This modi\ufb01cation improves the tracking capability of single component vibrations and provides reliable position tracking for several other di\ufb00erent types of vibration dynamics. In addition, the EKF method is more reliable at higher noise levels. More speci\ufb01cally, for a single component vibration, the mean square error (MSE) of the original method is .2279, while the MSE of the method presented in this paper is .1503. Therefore, the method presented in this paper improves the position estimate of the vibrating target by 34% when SNR = 15 dB. For the multicomponent vibrations, the mean square error of the estimated target position is reduced b 76% when SNR = 15 dB. The original EKF method and the modi\ufb01ed EKF method as well as simulations for various target vibration dynamics are provided in this thesis.\u2

You Think, Therefore I Am: Crowdsourcing Consciousness

Where would I go if I wanted to step into your mind? This question has long puzzled both scientists and philosophers alike. Intuitively, we may point to our heads, viewing the brain as a mysterious black box from which experience somehow emerges. Suppose we could really step-in to someone\u27s brain and see firsthand the firing of the neurons and networks that underlie our behaviors, would we expect to stumble across a single place where everything magically comes together? Unsurprisingly, no such place appears to exist. Does this mean that the contents of your mind are inaccessible to others? The purpose of this talk is to turn the mind inside-out, exploring the ways in which the mental experiences we see think are privy only to ourselves, are actually much more of a shared, social phenomenon. Though consciousness may be a sort of island inhabited only by you, the island does not exist in isolation. Rather, it is shaped by, and depends on, the presence of other minds. In this sense, it is perhaps better to see consciousness as an archipelago: a group of islands, each independent, though defined by their relationship to others

A Growing Concern: Modern Slavery and Agricultural Production in Brazil and South Asia

The modern use of slave labor in the production of agriculture takes many forms. In Brazil, the ability of powerful landowners to repress poor workers is an important element of large-scale agricultural production. In South Asia, cultural norms and traditions are used to exploit the most vulnerable communities. In both examples, inequity and poverty are implicit, and debt is a tool used to legitimize bondage

The Phenomenology of it All

Who is consumed when we read? Does the reader consume the text or does it consume us? This essay explores the complex and possibly parasitic relationship between reader and text. This unique exchange of knowledge and ideas between reader and texts during this relationship is the phenomenology of reading. During this, the text is transformed via the consciousness of the reader from a passive, inanimate object to an active living breathing immortal entity that transcends both space and time. In doing so, the unhuman text becomes an active consumer of the human reader in the same way the reader believes they are consuming the text. This mutual consumption by the text and the reader has a profound effect. It allows the reader to converse with a text in a wholly unique way that no other person will experience. It also transforms a text from paper and ink into a God-like figure whose ideas can torment and touch the souls of man for centuries after its initial creation. The question that haunts this paper is who is left standing after the interaction between reader and text? Is it the reader with a newfound wealth of knowledge after having engaged with and consumed the text or is it the text who stands before us having found a new host to spread its gospel

Crowdsourcing Consciousness: You Think, Therefore I Am

The challenge to understand consciousness is a centuries-old interdisciplinary research program. The search entails fundamental questions about our nature - the desire to understand who we are has been around for nearly as long as experience itself. It is also one of the most important questions we can ask; meaning itself is predicated on having some sort of conscious experiencer for whom something can matter. Given the magnitude and intractability of explaining the paradox of how consciousness can be at once the most obvious thing in the universe, and also the most inaccessible, the endeavor is a tremendous undertaking. Until somewhat recently, there has been little cross-talk between these disciplines; and in the absence of collaboration, a territorial dispute has emerged. The purpose of this thesis is two-fold: first, to trace a narrative thread across the history of thought by exploring philosophical theories dating back to ancient Greece, through the authoritatively scientific thought of the modem day. The second aim of this project is one of consilience, wherein by starting a dialogue between two approaches, that of science and philosophy, sincere progress can be made. In conclusion, the thesis ends with a provocation: much of our intimate experience is crowdsourced, and we are inescapably social