3,947 research outputs found
An Analysis of The Dynamic Properties of The American Depositary Receipt Cross Market Premium
The American Depositary Receipt (ADR) cross-market premium is studied over a 20 year period. The dynamic properties of the cross-market premium are studied for the first time in a nonlinear smooth error correction framework using a smooth transition error correction model (STECM) and compared against a linear model and two other nonlinear model specifications. The results indicate the ADR cross-market premium is more appropriately estimated when the nonlinearity, smooth transition, and cointegration properties present in the premium are estimated simultaneously with a STECM. The estimates of the STECM indicate arbitrage opportunities in the ADR market are rare and dissipate quickly. The forecasting properties of the STECM are found to be superior to that of the linear model using the squared error prediction error as the criterion. The impact of the 2007 – 2009 financial crisis over the ADR cross-market premium is analyzed by constructing a cross-market premium index. It is found that the financial crisis increased the volatility of the cross-market premium during the crisis and receded after the crisis passed
Laboratorio Virtual de Física Cuántica
El laboratorio virtual de física cuántica simula algunas de las experiencias que los estudiantes deben realizar en la asignatura Laboratorio de Física Cuántica del tercer curso del Grado en Física. Inicialmente, comenzó con la simulación del efecto fotoeléctrico y difracción de electrones. Ahora dispone de algunas simulaciones más. Este laboratorio virtual está diseñado como una herramienta para hacer más accesibles y comprensibles las experiencias del mundo cuántico y para familiarizar al estudiante con los procedimientos de medida y principios básicos de las experiencias de física cuántica.The Quantum Physics Virtual Lab simulates some of the experiences that the students must face at the Quantum Physics Laboratory in the third year of studies in Physics. Initially, the project was making the simulation of the electron diffraction and photoelectric effect experiences. Now it has some other simulations. The Virtual Lab is thought as a training tool to make accessible and comprehensive the experience and to get the student familiar with the measurement procedure and basic principles of the experience that afterwards he will have to do at the real Lab
Las élites partidarias. Notas para estudio de las minorías incidentes en las organizaciones políticas
This paper explores the phenomenon of incidencial minorities in political parties. From a review of sociological literature, it discusses the possibility that the classical notion of elites should be bounded to the concept of incidencial minorities and specify their relationship to the political conduction problem as an expression of the political power, common in political sociology. It’s proposed that relevant aspects to describe the phenomenon are the organized character of these minorities; their function of providing resources of operation to political conduction; their position regarding this incidence; their tendency to stabilize the incidencial position by institutionalizing their functions and members; the possibility of holding a political project of conduction and the willingness to compete for the execution of this project.Este artículo explora conceptualmente el fenómeno de las minorías incidentes en los partidos políticos. A partir de la revisión de la literatura sociológica asociada al tema se discute la posibilidad de que la noción clásica de élites debe ser acotada a la de minorías incidentes y especificar su relación con el problema de la conducción como expresión del problema del poder, habitual en la sociología política. Se propone que aspectos relevantes para la descripción del fenómeno son el carácter organizado de esas minorías; su función de proveer recursos de operación a la conducción; su posición incidente respecto de esta; su tendencia a estabilizarse en la posición incidente mediante la institucionalización de sus funciones y miembros; la posibilidad de contener un proyecto de conducción y la disposición a competir por la ejecución de ese proyecto
Interoperable Digital Proximity Tracing protocol (IDPT)
Draft Version 2, 19/05/2020, 25/05/2020This document introduces the Interoperable Digital Proximity Tracing (IDPT) protocol, that can be run by applications that also run the DP3T digital proximity tracking protocol to enable interoperability with the ROBERT digital proximity tracking protocol . We believe that the same mechanism can be adapted to allow interoperability between other decentralized and centralized digital proximity tracing protocols, but analysis of this is kept out of the scope of the document.
The IDPT protocol avoids the reidentification attack of positive-tested users of the centralised system that was claimed to be an inherent property of interoperability systems , as in IDPT the system does not publish the list of decentralised ephemeral identifier that were at risk of exposure of users of app R. Moreover, it avoids the possibility of creation of proximity graphs for users of IDPT who were in contact with users of ROBERT.
As is well known, the current iOS and Android Exposure Notification API only supports protocols of the distributed class. Due to this lack of support for centralized approaches, the implementation of the IDPT protocol has the same known difficulties as ROBERT, which appear mainly when applications are running in the background. Additionally, since devices must transmit more BLE beacons per second, we expect that devices running IDPT will have higher power consumption compared to implementing a pure DP3T mechanism.
We believe that, in practice, the use of IDPT in countries where majority of users of DP3T-type applications should be optional, mainly in areas where the presence of R nodes is likely (for example, large cities, tourist areas, airports, etc.). Another situation in which the use of IDPT could be adequate is when a user of the app I visits a country where the majority of the population uses R application. In addition, a country could introduce a DP3T application in a first phase, and only later incorporate IDPT.Preprin
Roaring 20s: A Self-Produced Visual EP
This project aims to develop a visual EP that will position the creator as a writer, musician, music producer, video producer, engineer & programmer. Through the process of pre- production, production, mixing and creating visuals, a project titled Roaring 20s will be developed that will innovate and push the creative boundaries within the creator. The EP will consist of four songs that will carry a theme, and originally were going to have a visual cohesive story, but due to unforeseen circumstances, evolved to accompanying lyric videos that illustrate and evoke the emotions each song is conveying. The author comes from a background of home studio audiovisuals. Therefore, this project aims to elevate the author’s skills with the goal of developing professional audiovisual production. This will be accomplished through the use of studio knowledge and etiquette applying songwriting, production, engineering and video production/editing learned throughout the year at Berklee College of Music.https://remix.berklee.edu/graduate-studies-production-technology/1204/thumbnail.jp
Study of the Influence of Helical Milling Parameters on the Quality of Holes in the UNS R56400 Alloy
Helical milling has been positioned as an alternative to conventional drilling, where the advantages it offers make it very attractive for use on difficult-to-machine alloys such as the titanium alloy UNS R56400. However, the correlation between the indicator of hole quality and the kinematic parameters has rarely been studied. The kinematics are what bring most advantages and that is why it is necessary to know their influence. In this aspect, there are different focuses of problems associated with the complexity of the process kinematics, which makes it necessary to undertake a deeper analysis of the process and to carry out a preliminary study. To address this problem, a DOE (Design of Experiments) is proposed to identify the sensitivity and the main trends of the properties that define the quality holes with respect to the kinematic parameters. At the same time, a nomenclature is proposed to unify and avoid misinterpretations. This study has allowed us to obtain conclusive results that offer very relevant information for future researc
The VirS/VirR two-component system regulates the anaerobic cytotoxicity, intestinal pathogenicity, and enterotoxemic lethality of Clostridium perfringens type C isolate CN3685.
Clostridium perfringens vegetative cells cause both histotoxic infections (e.g., gas gangrene) and diseases originating in the intestines (e.g., hemorrhagic necrotizing enteritis or lethal enterotoxemia). Despite their medical and veterinary importance, the molecular pathogenicity of C. perfringens vegetative cells causing diseases of intestinal origin remains poorly understood. However, C. perfringens beta toxin (CPB) was recently shown to be important when vegetative cells of C. perfringens type C strain CN3685 induce hemorrhagic necrotizing enteritis and lethal enterotoxemia. Additionally, the VirS/VirR two-component regulatory system was found to control CPB production by CN3685 vegetative cells during aerobic infection of cultured enterocyte-like Caco-2 cells. Using an isogenic virR null mutant, the current study now reports that the VirS/VirR system also regulates CN3685 cytotoxicity during infection of Caco-2 cells under anaerobic conditions, as found in the intestines. More importantly, the virR mutant lost the ability to cause hemorrhagic necrotic enteritis in rabbit small intestinal loops. Western blot analyses demonstrated that the VirS/VirR system mediates necrotizing enteritis, at least in part, by controlling in vivo CPB production. In addition, vegetative cells of the isogenic virR null mutant were, relative to wild-type vegetative cells, strongly attenuated in their lethality in a mouse enterotoxemia model. Collectively, these results identify the first regulator of in vivo pathogenicity for C. perfringens vegetative cells causing disease originating in the complex intestinal environment. Since VirS/VirR also mediates histotoxic infections, this two-component regulatory system now assumes a global role in regulating a spectrum of infections caused by C. perfringens vegetative cells
Self-Calibration Methods for Uncontrolled Environments in Sensor Networks: A Reference Survey
Growing progress in sensor technology has constantly expanded the number and
range of low-cost, small, and portable sensors on the market, increasing the
number and type of physical phenomena that can be measured with wirelessly
connected sensors. Large-scale deployments of wireless sensor networks (WSN)
involving hundreds or thousands of devices and limited budgets often constrain
the choice of sensing hardware, which generally has reduced accuracy,
precision, and reliability. Therefore, it is challenging to achieve good data
quality and maintain error-free measurements during the whole system lifetime.
Self-calibration or recalibration in ad hoc sensor networks to preserve data
quality is essential, yet challenging, for several reasons, such as the
existence of random noise and the absence of suitable general models.
Calibration performed in the field, without accurate and controlled
instrumentation, is said to be in an uncontrolled environment. This paper
provides current and fundamental self-calibration approaches and models for
wireless sensor networks in uncontrolled environments
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