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In this paper we postulate different scenarios based on two copula models under the format C(u, v)= uv + f (u)g(v) for suitable functions f and g, see Rodríguez-Lallena & Úbeda Flores (2004) [4] and Nelsen et al. (1997) [3]. We used these copulas to model the dependence between two currencies quoted relative to the U.S. Dollar, the Canadian Dollar and the South Korean Won. We assume a Bayesian approach to estimate the copulas parameters, then we estimate the impact of losses on the South Korean Won on the Canadian Dollar. [ABSTRACT FROM AUTHOR]

The use of copulas to model the dependence between indicators leads us to observe the different methods of estimation and its applicability, given practical circumstances, such as having small databases. For this reason, Bayesian methods under the scope of copulas come to show immense utility. In this paper, we investigate how the responses of the Asymmetric Cubic Sections copula model are affected when we vary the prior distributions display over the model parameters. We use as a reference setting a non-informative prior distribution and we observe the effect of the other prior distributions in relation to it. We used this diversity of scenarios to map the possible degrees of dependence between two educational scores obtained by students of the undergraduate course of statistics at the University of Campinas in 2014. [ABSTRACT FROM AUTHOR]

In this paper we investigate the behavior of the conditional probability Prob(U > u|V > v) of two records coming from students of an undergraduate course, where U is the score of calculus I, scaled in [0,1] and V is the score of physics scaled in [0,1], the physics subject is part of the admission test of the university. For purposes of comparison, we consider two different undergraduate courses, electrical engineering and mechanical engineering, during nine years, from 2003 to 2011. Through a Bayesian perspective we estimate Prob(U > u|V > v) year by year and course by course. We conclude that U is right tail increasing in V, in both courses and for all the years. Moreover, over these nine years, we observe different ranges of variability for the estimated probabilities of electrical engineering when compared to the estimated probabilities of mechanical engineering. [ABSTRACT FROM AUTHOR]

In this paper we investigate the performance of a copula type Gumbel-Barnett, for prediction of the dependence between two variables, X and Y. We fit a copula, using a sample of observations collected at time t and we define predictive areas, at different levels, to detect specific changes in a sample at time t +1, both samples are governed by the same law (copula). The study addresses the more general problem of detecting dependence changes during different periods of time. This work is developed under a Bayesian perspective, a procedure that allows working with small sample sizes and under different assumptions introduced in the model through the prior distribution. [ABSTRACT FROM AUTHOR]

We introduce the concept of cumulative conditional expectation function. This is a quantity that provides statistical support for making decisions in applied problems. The goal of this paper is to find an analytical expression for upper and lower bounds of this function, assuming stochastic dependence types as being the underlying random structure. [ABSTRACT FROM AUTHOR]

The Asymmetric Cubic Sections copula family is used to describe the dependence between language and mathematics scores of admission test. The parameters of the copula are annually estimated by means of a non-informative Bayesian method. The application focus on measuring the impact of conditioning language result to a mathematics minimum grade and vice-versa, this paper shows some initial results in that line. In addition, the analytical expression for each conditional expectation is shown together with a description of its monotonic behavior. [ABSTRACT FROM AUTHOR]

In this paper we address the problem of simultaneously modeling two financial series of the daily returns' direction (up/down variation) of an asset. We describe jointly both series by using a new family of Markov models called Partition Markov Models. This family has the characteristic of finding a Markov model with a minimal number of parameters. However, sometimes the sample size does not allow to extract enough information about the model. Then, we develop a copula based methodology to correct the joint probabilities by using the marginal models obtained by the Partition Markov Models. [ABSTRACT FROM AUTHOR]

In this paper it was applied a new Bayesian approach to model the dependence between two variables of interest in public policy: "Gonorrhea Rates per 100,000 Population" and "400% Federal Poverty Level and over" with a small number of paired observations (one pair for each U.S. state). We use a mixture of Gumbel-Barnett copulas suitable to represent situations with weak and negative dependence, which is the case treated here. The methodology allows even making a prediction of the dependence between the variables from one year to another, showing whether there was any alteration in the dependence. [ABSTRACT FROM AUTHOR]

Solving suitable evolution equations, we construct a 1-parameter family of balanced Hermitian structures starting with a 5-dimensional nilmanifold endowed with a balanced SU (2)-structure and we show that the holonomy of the Bismut connection of the associated balanced metrics is equal to SU (3). [ABSTRACT FROM AUTHOR]

A long term project, devoted to the photometric (CCD) study of the stellar variability in young (1–100 Myr) clusters and associations, has motivated us to gather all the tools that we use for the data reduction and analysis. Special effort is made on the code developed for the differential photometry, in particular, on the computation of an artificial comparison star. One goal of this poster is to contact other groups who are working (or have worked) on pipelines for the reduction and analysis of photometric time-series. [ABSTRACT FROM AUTHOR]

We present numerical results related to the direct and the inverse problems in electrocardiography. The electrical activity of the heart is described by the bidomain equations. The electrocardiograms (ECGs) recorded in different points on the body surface are obtained by coupling the bidomain equation to a Laplace equation in the torso. The simulated ECGs are quite satisfactory. As regards the inverse problem, our goal is to estimate the parameters of the bidomain-torso model. Here we present some preliminary results of a parameter estimation for the torso model. [ABSTRACT FROM AUTHOR]

This study is addressed to obtain a design methodology for integrated security sub-modules (constituting the suspension and steering modules) in the car manufacturing industry. The sub-modules are made up of a steel structure and anchorage elements (rubber-metal or plastic-metal), which undergo separate surface treatments to prevent corrosion. Afterwards, the elements are traditionally joined by means of adhesives and screws. This process involves a great number of stages, low quality union methods and generation of corrosion areas that shorten its useful life. This methodology provides automotive suppliers an additional added value and cost reduction, allowing them to increase its competitiveness in a sector that faces the transition from the traditional supply chain to a strategic value chain. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work we propose the construction of confidence bands for Kendall plots, based on asymptotic confidence intervals for quantiles of Kendall's distributions. The main application explored here is from the linguistic field. We analyze specifically the relationship between values of the acoustical correlate 'fundamental frequency' (F0) of pretonic syllables perceived as bearing secondary stresses and values of other pretonic syllables adjacent to those, in Brazilian Portuguese (EP) and European Portuguese (EP) data. Our hypothesis is this relationship can be a cue to the secondary stress perception by BP and EP speakers. From the statistical point of view, we obtained that for the two varieties of Portuguese the dependence is modeled by Gumbel's copulas. [ABSTRACT FROM AUTHOR]

Different Love-wave sensors have been developed in order to detect low-levels of chemical warfare agents for security applications. The different types of sensors have been realized using quartz and LiTaO3, as piezoelectric substrates, and SiO2 and Novolac, as guiding layers. Excellent results have been achieved with the sensors fabricated, measuring up to 200 ppb of DMMP. [ABSTRACT FROM AUTHOR]

The Diamond Beamline I13L is dedicated to imaging on the micron- and nano-lengthscale, operating in the energy range between 6 and 30 keV. For this purpose two independent stations have been built. The imaging branch is fully operational for micro-tomography and in-line phase contrast imaging with micrometer resolution. Currently a full-field microscope providing 50nm spatial resolution over a field of view of 100µm is being tested. On the coherence branch, coherent diffraction imaging techniques such as ptychography and coherent X-ray Bragg diffraction are currently developed. The beamline contains a number of unique features. The machine layout has been modified to the so-called mini-beta scheme, providing significantly increased flux from the two canted undulators. New instrumental designs such as a robot arm for the detector in diffraction experiments have been employed. The imaging branch is operated in collaboration with Manchester University, called therefore the Diamond-Manchester Branchline. [ABSTRACT FROM AUTHOR]

The Diamond Imaging and Coherence beamline I13 consists of two independent branchlines for imaging in real and reciprocal space. Different microscopies are available providing a range of spatial resolution from 5µm to potentially 5nm. The beamline operates in the energy range of 6-35keV covering different scientific areas such as biomedicine, materials science and geophysics. Several original devices have been developed at the beamline, such as the EXCALIBUR photon counting detector and the combined robot arms for coherent X-ray diffraction. [ABSTRACT FROM AUTHOR]

The "Neutrino Experiment with a Xenon TPC" (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too. [ABSTRACT FROM AUTHOR]

The 'Neutrino Experiment with a Xenon TPC' (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too. [ABSTRACT FROM AUTHOR]

We present an overview of our ongoing systematic search for wide (sub)stellar companions around the stars known to host rad-vel planets. By using a relatively large field of view and going very deep, our survey can find all directly detectable stellar and massive brown dwarf companions (m>40 MJup) within a 1000 AU orbit. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]