Stochastic prediction of wire coupling interference

Many EMC analyses of complex systems frequently result in a statement that insufficient knowledge is available to describe accurately the internal relationships of the system's components. This lack of information precludes any rigorous deterministic prediction and, in principle, requires that we express the uncertainties within the model. This paper shows the practical feasibility of stochastic prediction, as an alternative to deterministic simulation, applied to a class of EMC problems intrinsically affected by randomness. The evaluation of the crosstalk in standard cable bundles, in which several wires are tightly and randomly wrapped together, is the concrete problem that we investigate in this context. We developed a technique based on solving the nonuniform multiconductor transmission lines (MTL) for many randomly generated wires' geometries to obtain many crosstalk samples for a single frequency. Finally we validated the method, setting up a case study with published experimental result

A new antenna concept for satellite communications

A novel antenna configuration of two reflecting surfaces and a phased array is examined for application to satellite communications and shown to be superior in every respect to earlier designs for service to the continental United States from synchronous orbit. The vignetting that afflicts other two reflector optical systems is eliminated by use of a reflecting field element. The remaining aberrations, predominantly coma, are isolated in the time delay distribution at the surface of the array and can be compensated by ordinary array techniques. The optics exhibits infinite bandwidth and the frequency range is limited only by the design of the array

The latin american metropolis revisited beyond globalization

Las transformaciones metropolitanas de las últimas décadas en América latina han sido considerables. Ello genera la necesidad de una revitalizada discusión sobre la nueva naturaleza de la ciudad latinoamericana, intentando identificar rasgos comunes y singularidades en las grandes metrópolis de la región. Particularmente, este trabajo intenta discutir acerca de las nuevas tensiones que en esos nuevos escenarios metropolitanos están evidenciándose, tales como las dificultades del estado local para entender y metabolizar dichos cambios y desarrollar formas eficaces de intervención sobre el espacio urbano; el avance de un proyecto urbano hegemónico corporizado principalmente por el capital financiero e inmobiliario; y el agravamiento de una estructura socio-económica territorial históricamente desigual. Como trasfondo de estas tensiones, aparecen interrogantes significativos: ¿Es posible pensar en una ciudad latinoamericana competitiva, productiva y a su vez socialmente justa y territorialmente integradora? ¿Qué imágenes, qué modelos de ciudad van apareciendo como consecuencia de los acelerados cambios sufridos por las metrópolis, y, paralelamente, qué imaginarios, qué utopías urbanas están surgiendo?ENG: The Metropolitan transformations in Latin America have been considerable during the last decades. This creates the need for a revitalized discussion on the new nature of the Latin American city, trying to identify common features and singularities in the great metropolis of the region. In particular, this paper tries to discuss about the new tensions that these new Metropolitan scenarios are showing, such as the difficulties of local State to understand and metabolize these changes and develop effective forms of intervention on urban space; the advance of a hegemonic urban project represented mainly by financial and real estate capital; and the worsening of an historically unequal territorial socio-economic structure. As a background to these tensions, significant questions appear: Is it possible to think in a competitive, productive and in turn socially fair and territorially integrated Latin American city? What images, what city models are emerging as a result of the accelerated changes suffered by the metropolis, and, at the same time, what imaginary, what urban utopias are emerging?Peer Reviewe

“An almost necessary good”: sugar consumption, politics and industry in the Kingdom of Naples during the revolutionary and Napoleonic age

During the late modern age, sugar moved from being a luxury to a necessary good. The Napoleonic era is an excellent point of view to examine this process. Indeed, the Napoleonic Wars interrupted the supply of cane sugar in Europe, determining reactions on the part of consumers but even from politicians and savants interested in promoting and finding out an alternative source of sugar, finally identified in the beet. The article explores the subject with special regard to the Kingdom of Naples. It describes the trend in sugar consumption during the eighteenth century, the effects of the Continental Blockade on consumers’ behaviour and the enterprises (public, academic and industrial) taken in those years to produce an indigenous sugar.zucchero; blocco continentale; Regno di Napoli; innovazione; imprenditorialità

Dynamics, morphologies and singularities in the metropolitan restructuring of Buenos Aires

El artículo se propone analizar las principales transformaciones territoriales en la Región Metropolitana de Buenos Aires durante las dos últimas décadas (1990-2010), resaltando las semejanzas y diferencias entre ellas, y tomando como referencia la experiencia de otras grandes metrópolis latinoamericanas. Se tratan de interpretar las tendencias hacia los procesos y formas de la "globalización", al mismo tiempo que se ponen en valor algunas singularidades en los patrones de localización, comportamientos y morfologías propias o específicas de esta región. Así, el trabajo se centra en el análisis de la reconfiguración de la centralidad metropolitana (consolidación de antiguos centros y subcentros, y surgimiento de nuevas centralidades complejas); la relocalización de la actividad productiva y la difusión de parques industriales; y la reestructuración sociohabitacional (suburbanización residencial, "verticalización" de tejidos consolidados y expansión de asentamientos informales). Este recorrido se considera fundamental a fin de aportar argumentos a la discusión sobre el modelo territorial deseable, la problemática de la gobernabilidad metropolitana y los lineamientos e instrumentos de ordenación urbanística necesarios a efectos de compensar las distorsiones que la acción del capital tiende a generar sobre el territorio metropolitano.ENG: The article intends to analyze the major territorial transformations in the metropolitan region of Buenos Aires over the past two decades (1990-2010), highlighting the similarities and differences between them, and in reference to the experience of other large Latin American metropolis. It is tried to interpret trends toward processes and forms of "globalization", at the same time that some singularities in localization patterns, specific behaviors and morphologies of this region are assessed. Thus the work focuses on the analysis of metropolitan centrality reconfiguration (consolidation of existing centers and subcenters, and emergence of new complex centralities); productive activities relocation and industrial parks diffusion; and housing restructuring (residential suburbanization, "verticalization" of consolidated urban fabric and slums expansion). This path is considered essential in order to provide arguments to the discussion on the desirable territorial model, the problem of metropolitan governance and necessary guidelines and urban planning tools to compensate the distortions that market action tends to generate in metropolitan areas.Peer Reviewe

New territories of leisure and commerce in the metropolitan region of Buenos Aires : (1990-2008)

El presente artículo se centra en el análisis del surgimiento y difusión de los grandes nodos del consumo y el ocio en la Región Metropolitana de Buenos Aires (RMBA) y su contribución a las nuevas formas del crecimiento metropolitano y a la definición de nuevas espacialidades urbanas. Desde ese encuadre, se inscriben aportes más específicos como la definición de tipologías de grandes superficies y concentraciones comerciales, basadas en sus modalidades de implantación territorial y destino funcional. En este sentido, el análisis de casos seleccionados y de sus combinaciones de uso, formas de accesibilidad viaria y relación con el tejido urbano existente, pretende adicionalmente adentrarnos en la discusión sobre los procesos de fragmentación y segregación que los nuevos artefactos urbanos parecen inducir o fortalecer; así como también indagar acerca de las posibilidades de integración y complementariedad que un adecuado planeamiento territorial puede ofrecer a las nuevas centralidades y subcentralidades comerciales.This article focuses on the analysis of emergence and spread of major nodes of consumption and leisure in the metropolitan region of Buenos Aires (RMBA), and their contribution to a new kind of metropolitan growth and the definition of new urban spatialities. From that point of view, more specific inputs are included such as the definition of typologies of large retail establishments and commercial concentrations, based on their territorial settlement and functional modalities. In this regard, the analysis of selected cases and their uses combinations, kinds of road accessibility and relationship with the existing urban fabric, intends, in addition, diving in the discussion of fragmentation and segregation processes that new urban artifacts seem to induce or strengthen; and also to examine the possibilities of integration and complementarity that an appropriate territorial planning could offer to new commercial centralities and subcentralities.Fil: Vecslir, Lorena. Universidad de Buenos AiresFil: Ciccolella, Pablo. Universidad de Buenos Aire

Cloud-based highly parallel execution of t-SNE and SPADE with metaclustering for analysis and visualization of large single-cell datasets

The use of machine learning techniques, in particular unsupervised clustering and dimensionality reduction algorithms, is quickly becoming a standard workflow for identifying and visualizing biological populations from within high-dimensional data. These methods allow researchers to approach data analysis without the bias and subjectivity that has traditionally been standard in the field. Algorithms have context-dependent strengths and weaknesses. Across algorithms, an inability to scale computation to large datasets is a common theme. Most algorithms are designed and distributed to run on individual computers where memory and CPU are quickly exhausted by large datasets. Even when high-performance compute resources are available, algorithms often don't scale to large datasets as a fundamental property of their design. If they do, it might result in an untenable increase in runtime or diminished quality of results. t-SNE and SPADE are two well-published algorithms that suffer problems as discussed above after datasets exceed a number of observations on the order of 1 million. This study introduces an alternative approach to the use of SPADE and t- SNE whereby a dataset is divided and distributed across numerous compute nodes in the cloud to process independently in parallel. The results of each computation are then combined in a metaclustering step for final visualization and analysis. The improvement in execution speed as a function of degree of parallelization is established. The method is validated against a non-parallel analysis of the same dataset to establish concordance of identified populations. The workflow is executed on Cytobank for portability to other researchers

Legal Aspects of Aerobic Capacity: Objective Evidence of the Ability to Work Part I: Age as a Bona Fide Occupational Qualification (BFOQ)

This two part series examines the legal issues relevant to aerobic capacity as objective evidence of the ability to work. Law relevant to two issues will be reviewed: (1) age as a bona fide occupational qualification (BFOQ) for certain occupations where public safety is at stake (police and wildlife officers), and (2) chronic fatigue syndrome as a medically diagnosed condition that causes disability for work. In case law for both issues, aerobic capacity is offered as objective evidence of the physical ability (disability) to perform work related duties that may be strenuous as in the case of a police officer, or light/sedentary as in the case of a disabled individual. The role of the expert in determining and interpreting the relevance of aerobic capacity to the physiological demands of a job is central to court decisions for both issues

Il setificio meridionale tra età rivoluzionaria, decennio francese e restaurazione: dinamiche di mercato e nuovi assetti produttivi

The article describes the structure of sericulture and silk industry in southern Italy before the commercial crisis of the revolutionary and Napoleonic period. Then, traces the different stages of the crisis, which lasted 25 years but had an uneven course. Finally, it describes the consequences of the crisis on raw-silk production levels, on the diffusion of innovations and on the urban silk industry, showing that, if in a context of general decline, the crisis had different and even unexpected, favourable outcomes at a regional level

viSNE fine-tuning enables better resolution of cell populations

t-Distributed Stochastic Neighbor Embedding (t-SNE or viSNE) is a dimensionality reduction algorithm that allows visualization of complex high-dimensional cytometry data as a two-dimensional distribution or " map ". These maps can be interrogated by human-guided or automated techniques to categorize single cell data into relevant biological populations and otherwise visualize important differences between samples. The method has been extensively adopted and reported in the literature to be superior to traditional biaxial gating. The analyst must carefully choose the parameters of a t-SNE computation, as incorrectly chosen parameters might create artifacts that make the resulting map difficult or impossible to interpret. The correct choice of algorithm parameters is complicated by a lack of agreed-upon quantitative framework for assessing the quality of algorithm results. Gauging result quality currently relies on subjective visual evaluation by an experienced t-SNE user. To overcome these limitations, we used Cytobank viSNE engine for all t-SNE analyses and employed 18-parameter flow cytometry data as well as 32-parameter mass cytometry data of varying numbers of events to optimize t-SNE parameters such as total number of iterations and perplexity. We also investigated the utility of Kullback-Liebler (KL) divergence as a metric for map quality as well as SPADE clustering as an indirect measure of multidimensional data integrity when flattened into t-SNE coordinates. We have established the imperative requirement for the number of t-SNE analysis optimization steps ('iteration number') to be scaled with the total number of data points (events) in the set, suggesting that a number of existing software solutions produce unclear t-SNE maps of flow and mass cytometry data due to built-in user control restrictions. We also evaluated lower-level parameters within the t-SNE code that control the 'early exaggeration' stage initially introduced into t-SNE algorithm for better map optimization. These parameters are not available as part of the standard algorithm interface, but we found that they can be tuned to produce high quality results in shorter periods of time, avoiding unnecessary increases of both analysis duration and computation cost. Therefore, our approach allows to fine-tune the t-SNE analysis to ensure both optimal resolution of t-SNE low-dimensional maps and better faithfulness of their presentation of high-parameter cytometry data