3,302 research outputs found

    Belmont Criminal Law Journal Symposium 2017: Judicial Panel

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    Transcript of the Judicial Panel given during the 2017 Symposium featuring Chief Justice Jeffrey S. Bivins, Judge Joseph A. Woodruff, Judge Timothy L. Easter, and Judge Angelita B. Dalton

    Optimal Principal Component Analysis in Distributed and Streaming Models

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    We study the Principal Component Analysis (PCA) problem in the distributed and streaming models of computation. Given a matrix A∈Rm×n,A \in R^{m \times n}, a rank parameter k<rank(A)k < rank(A), and an accuracy parameter 0<ϵ<10 < \epsilon < 1, we want to output an m×km \times k orthonormal matrix UU for which ∣∣A−UUTA∣∣F2≤(1+ϵ)⋅∣∣A−Ak∣∣F2, || A - U U^T A ||_F^2 \le \left(1 + \epsilon \right) \cdot || A - A_k||_F^2, where Ak∈Rm×nA_k \in R^{m \times n} is the best rank-kk approximation to AA. This paper provides improved algorithms for distributed PCA and streaming PCA.Comment: STOC2016 full versio

    Why Compact Tori For Fusion?

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    A compact torus (CT) has a toroidal magnetic and plasma geometry, but is contained within a simply-connected vacuum vessel such as a cylinder. Spheromaks and field-reversed configurations fall into this category. Compact tori are translatable and have a high engineering beta. The primary benefit of CTs for fusion is the absence of toroidal field and Ohmic Heating coils and the many problems brought on by them. Studying fusion-relevant plasma in simply-connected geometries affords the world fusion program both physics and technology opportunities not found in other configurations. This paper outlines the technology and physics opportunities of compact tori, and presents a cost model based on geometry for comparison with less compact configurations

    Renormalisation-theoretic analysis of non-equilibrium phase transitions II: The effect of perturbations on rate coefficients in the Becker-Doring equations

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    We study in detail the application of renormalisation theory to models of cluster aggregation and fragmentation of relevance to nucleation and growth processes. In particular, we investigate the Becker-Doring (BD) equations, originally formulated to describe and analyse non-equilibrium phase transitions, but more recently generalised to describe a wide range of physicochemical problems. We consider here rate coefficients which depend on the cluster size in a power-law fashion, but now perturbed by small amplitude random noise. Power-law rate coefficients arise naturally in the theory of surface-controlled nucleation and growth processes. The noisy perturbations on these rates reflect the effect of microscopic variations in such mean-field coefficients, thermal fluctuations and/or experimental uncertainties. In the present paper we generalise our earlier work that identified the nine classes into which all dynamical behaviour must fall by investigating how random perturbations of the rate coefficients influence the steady-state and kinetic behaviour of the coarse-grained, renormalised system. We are hence able to confirm the existence of a set of up to nine universality classes for such BD systems.Comment: 30 pages, to appear in J Phys A Math Ge

    CLIWOC multilingual meteorological dictionary

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    This dictionary is the first attempt to express the wealth of archaic logbook wind force terms in a form that is comprehensible to the modern-day reader. Oliver and Kington (1970) and Lamb (1982) have drawn attention to the importance of logbooks in climatic studies, and Lamb (1991) offered a conversion scale for early eighteenth century English wind force terms, but no studies have thus far pursued the matter to any greater depth. This text attempts to make good this deficiency, and is derived from the research undertaken by the CLIWOC project1 in which British, Dutch, French and Spanish naval and merchant logbooks from the period 1750 to 1850 were used to derive a global database of climatic information. At an early stage in the project it was apparent that many of the logbook weather terms, whilst conforming to a conventional vocabulary, possessed meanings that were unclear to twenty-first century readers or had changed over time. This was particularly the case for the important element of wind force; but no special plea is entered for the evolution in nautical vocabulary, which often reflected more wide-ranging changes in the respective native languages.The key objective was to translate the archaic vocabulary of the late eighteenth and early nineteenth century mariner into expressions directly comparable with the Beaufort Scale (see Appendix I). Only then could the projects scientific programme be embarked upon. This dictionary is the result of the largest undertaking into logbook studies that has yet been carried out. Several thousand logbooks from British, Dutch, French and Spanish archives were examined, and the exercise offered a unique opportunity to explore the vocabulary of the one hundred year period beginning in 1750. The logbooks from which the raw data have been abstracted range widely across the North and South Atlantic and the Indian Oceans. Only the Pacific, largely in consequence of the paucity of regular naval activity in that area, is not well represented. The range of climates encountered in this otherwise wide geographic domain gives ample opportunity for the full range of the mariners nautical weather vocabulary to be assessed, from the calms of the Equatorial regions, through the gales of the mid-latitude systems to the fearsome storms of the tropical latitudes. The Trade Winds belts, the Doldrums, the unsettled mid-latitudes, even the icy wastes of the high latitudes, are all embraced in this study. It is not here intended to pass any judgements on the climatological record of the logbooks, and this text seeks only to provide a means of understanding archaic wind force terms and, other than to indicate those items that were not commonly used, no information is given on the frequency with which different terms appeared in the logbooks. Attention is, furthermore, confined to Dutch, English, French and Spanish because these once great imperial powers were the only nations able to support wide-ranging ocean-going fleets with their attendant collections of logbooks and documents over this long period of time. The work is offered to the wider academic community in the hope that they will prove to be of as much value as it has been to the CLIWOC team

    Pre-maximum spectro-imaging of the Mira star T Lep with AMBER/VLTI

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    Diffuse envelopes around Mira variables are among the most important sources influencing the chemical evolution of galaxies. However they represent an observational challenge because of their complex spectral features and their rapid temporal variability. We constrained the exact brightness distribution of the Mira star TLep with a model-independent analysis. We obtained single-epoch interferometric observations with a dataset continuous in the spectral domain (1.5-2.4mum) and in the spatial domain (baselines ranging from 11 to 96m). We performed a model independent image reconstruction for each spectral bin using the MIRA software. We completed the analysis by modeling the data with a simple star+layer model inspired from the images. Reconstructed images confirm the general picture of a central star partially obscured by the surrounding molecular shell of changing opacity. At 1.7mum, the shell becomes optically thin, with corresponding emission appearing as a ring circling the star. This is the first direct evidence of the spherical morphology of the molecular shell. Model fitting confirmed a spherical layer of constant size and changing opacity over the wavelengths. Rough modeling points to a continuum opacity within the shell, in addition to the CO and H2O features. Accordingly, it appeared impossible to model the data by a photosphere alone in any of the spectral bins.Comment: Accepted in A&

    A Mixed-Method Multiple Case Study of Three Business Models for Local Healthy Food Delivery Systems in Underprivileged Urban Areas

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    Define a USDA food desert Analyze the three business models for benefits and deficiencies Identify methods for starting a sustainable mobile farmers market program. Over 40% of Berrien County Michigan land use is agricultural. Many products are fruits and vegetables. Yet, the county has six identified USDA defined Food Deserts. Past research, based on a mobile farmers market, confirmed local trends and deficits. The purpose for this research is to define a sustainable business model that delivers healthy local food options to USDA Food Deserts combating food inequity. A mixed method multiple case study was created to test three business models in one of the local Food Deserts. Results identify a sustainable model that provides local healthy food options. Model One developed lunchtime stops serving robust local businesses and community epicenters, with a goal of creating lunchtime profit, focusing evenings on service stops at a potential loss. Model Two required local farmers to provide produce at no cost to the market. Market locations were service stops embedded inside the residential community and stops increased to 15 per week. Model Three purchased local produce and focused stops on work and shopping locals, targeting the ALICE poverty segment. Models were tested for two weeks each with data collected for correlational comparison. Results show a high demand for lunch hour food options. Labor at such stops was increased over service stops. Model Two proved willingness from local farmers to support neighboring Food Deserts, yet sales didn’t equal market costs. Model Three demonstrated increased demand from ALICE segments. Conclusions indicate that sustainability could be reached with a hybrid model with limited volunteer intern positions. A three to five-year plan should be built with funding support ebbing with market growth
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