The tensor Goldstone multiplet for partially broken supersymmetry

We show that the tensor gauge multiplet of N=1 supersymmetry can serve as the Goldstone multiplet for partially broken rigid N=2 supersymmetry. We exploit a remarkable analogy with the Goldstone-Maxwell multiplet of hep-th/9608177 to find its nonlinear transformation law and its invariant Goldstone action. We demonstrate that the tensor multiplet has two dualities. The first transforms it into the chiral Goldstone multiplet; the other leaves it invariant.Comment: 7 pages, Latex. Expanded discussion of duality symmetrie

Reduced density of calbindin immunoreactive GABAergic neurons in major depressive disorder: relevance to neuroimaging studies and future directions

Background: Several lines of evidence suggest dysfunction of the γ-aminobutyric acid (GABA)ergic system in major depressive disorder. Neuroimaging studies report reduced levels of GABA in the dorsolateral prefrontal and occipital cortex of depressed patients. Our previous postmortem study re-vealed a reduction in the density and size of calbindin-immunoreactive (CB-IR) GABAergic neurons in the prefrontal cortex in major depressive disorder. The goal of this study was to test whether the changes in CB-IR neurons can also be detected in the occipital cortex, where neuroimaging studies report a prominent GABA decrease. Methods: A three-dimensional cell counting probe was used to assess the cell-packing density and size of CB-IR neurons in layer II of the occipital cortex in 10 major depressive disorder subjects and 10 psychiatrically healthy control subjects. Results: The density of CB-IR neurons was significantly decreased by 28% in major depressive dis-order subjects compared with the control group. The size of CB-IR neurons was unchanged in major depressive disorder subjects when compared with control subjects. Conclusions: The reduction in the density of CB-IR GABAergic neurons in the occipital cortex in depression is similar to that observed previously in the prefrontal cortex. Deficits in cortical GA-BAergic interneurons may contribute to the low GABA levels detected in neuroimaging studies in major depressive disorder patients. Future Directions: Experiments are proposed to determine whether or not decreases in calbindin-immunoreactivity are due to decreases in calbindin expression. Further experiments will be designed to investigate potential involvement of calbindin interactors in MDD

An auditory classifier employing a wavelet neural network implemented in a digital design

This thesis addresses the problem of classifying audio as either voice or music. The goal was to solve this problem by means of digital logic circuit, capable of performing the classification in real time. Since digital audio is essentially a discrete non-periodic timeseries, it was necessary to extract features from the audio which are suitable for classification. The discrete wavelet transform combined with a feature extraction method was found to produce such features. The task of classifying these features was found to be best performed by an artificial neural network. Collectively known as a wavelet neural network, the digital logic design implementation of this architecture was effective in correctly identifying the test data sets. The wavelet neural network was first implemented as a software model, to develop the network architecture and parameters, and to determine ideal results. The unconstrained software simulation was capable of correctly classifying test data sets with greater than 90% accuracy. This model was not feasible as a digital logic design however, as the size of the implementation would have been prohibitive. The size of the resulting hardware model was constrained by reducing the widths of the data paths and storage registers. The hardware implementation of the wavelet processor consisted of a novel pipelined design with a novel data-flow control structure. The neural network training was performed entirely in software by way of a novel training algorithm, and the resulting weights were made to be available to be uploaded to the hardware model. The digital design of the wavelet neural network was modeled in VHDL and was synthesized with Synplicity Synplify, using Actel ProASICPlus APA600 synthesized library cells with a target clock frequency of 11.025 KHz, to match the sampling rate of the digital audio. The results of the synthesis indicated that the design could operate at 15.6 MHz, and required 96,265 logic cells. The resulting constrained wavelet neural network processor was capable of correctly classifying test data sets with greater than 70% accuracy. Additional modeling showed that with a reasonable increase in hardware size, greater than 86% accuracy is attainable. This thesis focused on classifying audio as either voice or music, and future research could readily extend this work to the problem of speaker recognition and multimedia indexing

On a discrete version of Tanaka's theorem for maximal functions

In this paper we prove a discrete version of Tanaka's Theorem \cite{Ta} for the Hardy-Littlewood maximal operator in dimension $n=1$, both in the non-centered and centered cases. For the discrete non-centered maximal operator $\widetilde{M}$ we prove that, given a function $f: \mathbb{Z} \to \mathbb{R}$ of bounded variation, $$\textrm{Var}(\widetilde{M} f) \leq \textrm{Var}(f),$$ where $\textrm{Var}(f)$ represents the total variation of $f$. For the discrete centered maximal operator $M$ we prove that, given a function $f: \mathbb{Z} \to \mathbb{R}$ such that $f \in \ell^1(\mathbb{Z})$, $$\textrm{Var}(Mf) \leq C \|f\|_{\ell^1(\mathbb{Z})}.$$ This provides a positive solution to a question of Haj{\l}asz and Onninen \cite{HO} in the discrete one-dimensional case.Comment: V4 - Proof of Lemma 3 update

Establishing a Multibeam Sonar Evaluation Test Bed near Sidney, British Columbia

The Canadian Hydrographic Service (CHS), Naval Oceanographic Office (NAVOCEANO) and the Ocean Mapping Group of the University of New Brunswick (OMG) collaborated on establishing a multibeam sonar test bed in the vicinity of the Institute of Ocean Sciences in Sidney, British Columbia Canada. This paper describes the purpose of the sonar evaluation test bed, the trials and tribulations of two foreign governments collaborating on projects of mutual interest, the evaluation areas and their characteristics for sonar testing, and sample results of sonar evaluations using this test bed. Some target detection comparisons of several systems over a range of artificial sonar targets will also be given

Seamless Online Distribution of Amundsen Multibeam Data

Since 2003, all underway multibeam and sub-bottom data from the Canadian Coast Guard Ship Amundsen has been posted online within approximately six months of the end of each cruise. A custom interface allowing the user to access 15\u27 latitude by 30\u27 longitude mapsheets was implemented in 2006, allowing the user to download the bathymetric and backscatter data at 10 metre resolution. While this interface matched the underlying data management scheme implemented at the University of New Brunswick, the zoom and pan capability was at a fixed scale with limited contextual data. In the past few years, with the introduction of web-based geographic information systems (GIS) (e.g. Google Maps, Yahoo Maps, Bing Maps), there have been thousands of maps published online. These online GIS programs are a suitable platform to display the seven years of Amundsen coverage within the context of the GIS-served satellite imagery and allow the user to freely browse all data in a familiar interface. The challenge, however, for serving up third party data through these map engines is to efficiently cope with the multiple zoom levels and changing resolutions. Custom tiling software was developed to take all the raw data from the seven years of Amundsen (and others\u27) multibeam coverage and convert it into multiple scale resolution images suitable for interpretation by Google Maps. The images were stored in a pyramid structure utilizing Google\u27s map projection and uniquely named to reflect their georeferencing and resolution. This image pyramid is then accessed by Google Maps according to the user\u27s current zoom level to optimize visualization. This multi-resolution data is served up on demand from the University of New Brunswick for dynamic overlay on Google\u27s satellite data. This web interface allows any interested parties to easily view multibeam and sub-bottom data from the Pacific Ocean through the Canadian Arctic Archipelago and into the Atlantic Ocean. The broad overview helps to understand regional trends and then focus on areas of interest at high resolutions to see particular features. The web interface also provides a link to the 15\u27 by 30\u27 mapsheet model with full source traceability

Evidence of a Shift in the Short-Run Price Elasticity of Gasoline Demand

Understanding the sensitivity of gasoline demand to changes in prices and income has important implications for policies related to climate change, optimal taxation and national security, to name only a few. While the short-run price and income elasticities of gasoline demand in the United States have been studied extensively, the vast majority of these studies focus on consumer behavior in the 1970s and 1980s. There are a number of reasons to believe that current demand elasticities differ from these previous periods, as transportation analysts have hypothesized that behavioral and structural factors over the past several decades have changed the responsiveness of U.S. consumers to changes in gasoline prices. In this paper, we compare the price and income elasticities of gasoline demand in two periods of similarly high prices from 1975 to 1980 and 2001 to 2006. The short-run price elasticities differ considerably: and range from -0.034 to -0.077 during 2001 to 2006, versus -0.21 to -0.34 for 1975 to 1980. The estimated short-run income elasticities range from 0.21 to 0.75 and when estimated with the same models are not significantly different between the two periods.