Análisis y diseño de un procesador RISC simple para adquisición y proceso de datos

Aquest projecte té com a objectiu l'anàlisi de prestacions de processadors RISC de baix cost i el disseny d'un processador RISC simple per a aplicacions de propòsit general relacionades amb l'adquisició i el procés simple de dades. Com a resultat es presenta el processador SR3C de 32 bits i arquitectura RISC. Aquest processador s'ha descrit i simulat mitjançant el llenguatge de descripció de hardware VHDL i s'ha sintetitzat en una FPGA. El processador està preparat per poder utilitzar-se en SoCs reals gràcies al compliment de l'estàndard de busos Wishbone. A més també es pot utilitzar com plataforma educativa gràcies a l'essamblador i simulador desenvolupats.

A simple model of aggregate pension expenditure

This paper develops a simple model that can be used to analyze the long-term sustainability of the contributive pension system and the steady-state response of pension expenditure to changes in some key demographic and economic variables, in the characteristics of the average pensioner and in the parameters that describe how pensions are calculated in Spain as a function of workers' Social Security contribution histories.

Macroeconomics of extensive margins: a simple model

How do monopolistically competitive industries react to shocks in the context of a New Keynesian macro model? I bridge macroeconomics and trade theory by considering market dynamics. I use an analytically tractable closed-economy model with endogenous entry of firms and show the implications of markets structure for the transmission of real shocks on aggregate variables and welfare. Shock sources become crucial for the results: traditional productivity shocks cause an extensive effect on production; shocks on innovation cause an intensive impact. More patient populations bring the economy to a richer market, although it cushions the extensive effect after an innovation shock.

TDA-H más que un simple trastorno

El TDA-H es un trastorno que no solo afecta y dificulta al niño su aprendizaje, sino que sus relaciones sociales, su entorno se ven trastornados. Lo que provoca al niño con TDA-H un sentimiento de soledad y de inseguridad que afecta negativa y directamente a su autoestima, lo que acrecienta aun más su problemática. Por ello es importante que familia y escuela se alíen a la hora de luchar contra este trastorno, haciendo partícipe al niño en esta lucha, donde el trió familia-escuela-niñoTDA-H han de trabajar de manera simbiótica, para que el niño pueda superar todas las dificultades que este trastorno arrastra con él. El diagnostico temprano es imprescindible, pero se debe empezar a trabajar a partir de las primeras alarmas que se despierten y que suelen despertarse en la escuela. Esto aliviará e incluso esquivará algunos de los golpes que este niño TDA-H tendrá que ir superando, hasta iniciar su correcto tratamiento.

Hardy-Weinberg Equilibrium and the Ternary Plot

The Hardy-Weinberg law, formulated about 100 years ago, states that under certainassumptions, the three genotypes AA, AB and BB at a bi-allelic locus are expected to occur inthe proportions p2, 2pq, and q2 respectively, where p is the allele frequency of A, and q = 1-p.There are many statistical tests being used to check whether empirical marker data obeys theHardy-Weinberg principle. Among these are the classical xi-square test (with or withoutcontinuity correction), the likelihood ratio test, Fisher's Exact test, and exact tests in combinationwith Monte Carlo and Markov Chain algorithms. Tests for Hardy-Weinberg equilibrium (HWE)are numerical in nature, requiring the computation of a test statistic and a p-value.There is however, ample space for the use of graphics in HWE tests, in particular for the ternaryplot. Nowadays, many genetical studies are using genetical markers known as SingleNucleotide Polymorphisms (SNPs). SNP data comes in the form of counts, but from the countsone typically computes genotype frequencies and allele frequencies. These frequencies satisfythe unit-sum constraint, and their analysis therefore falls within the realm of compositional dataanalysis (Aitchison, 1986). SNPs are usually bi-allelic, which implies that the genotypefrequencies can be adequately represented in a ternary plot. Compositions that are in exactHWE describe a parabola in the ternary plot. Compositions for which HWE cannot be rejected ina statistical test are typically “close" to the parabola, whereas compositions that differsignificantly from HWE are “far". By rewriting the statistics used to test for HWE in terms ofheterozygote frequencies, acceptance regions for HWE can be obtained that can be depicted inthe ternary plot. This way, compositions can be tested for HWE purely on the basis of theirposition in the ternary plot (Graffelman & Morales, 2008). This leads to nice graphicalrepresentations where large numbers of SNPs can be tested for HWE in a single graph. Severalexamples of graphical tests for HWE (implemented in R software), will be shown, using SNPdata from different human populations

Moderating effects of management control systems and innovation on performance. Simple methods for correcting the effects of measurement error for interaction effects in small samples

In the accounting literature, interaction or moderating effects are usually assessed by means of OLS regression and summated rating scales are constructed to reduce measurement error bias. Structural equation models and two-stage least squares regression could be used to completely eliminate this bias, but large samples are needed. Partial Least Squares are appropriate for small samples but do not correct measurement error bias. In this article, disattenuated regression is discussed as a small sample alternative and is illustrated on data of Bisbe and Otley (in press) that examine the interaction effect of innovation and style of use of budgets on performance. Sizeable differences emerge between OLS and disattenuated regression

Relación de la susceptibilidad genética y de las características anatomopatológicas del cáncer de próstata con los polimorfismos de nucleótido simple

Actualmente no se disponen de marcadores biológicos específicos para la cáncer de próstata produciéndose en muchas ocasiones biopsias prostáticas innecesarias o un sobretratamientos para cánceres indolentes. Existen cada vez más un número mayor de publicaciones sobre cómo los polimorfismos de nucleótido simple (SNP) se relacionan con la susceptibilidad al cáncer de próstata o predecir con mayor precisión qué grado de agresividad adquiere la enfermedad. Se presenta una revisión bibliográfica de las investigaciones publicadas en PubMed desde el año 2000 hasta el 2012 que ponen de manifiesto la relación de los SNP con el riesgo a padecer cáncer de próstata y con sus características anatomopatológicas.

Simple finite field nuclear relaxation method for calculating vibrational contribution to degenerate four-wave mixing

A simple extended finite field nuclear relaxation procedure for calculating vibrational contributions to degenerate four-wave mixing (also known as the intensity-dependent refractive index) is presented. As a by-product one also obtains the static vibrationally averaged linear polarizability, as well as the first and second hyperpolarizability. The methodology is validated by illustrative calculations on the water molecule. Further possible extensions are suggested

Simple finite field method for calculation of static and dynamic vibrational hyperpolarizabilities: curvature contributions

In the static field limit, the vibrational hyperpolarizability consists of two contributions due to: (1) the shift in the equilibrium geometry (known as nuclear relaxation), and (2) the change in the shape of the potential energy surface (known as curvature). Simple finite field methods have previously been developed for evaluating these static field contributions and also for determining the effect of nuclear relaxation on dynamic vibrational hyperpolarizabilities in the infinite frequency approximation. In this paper the finite field approach is extended to include, within the infinite frequency approximation, the effect of curvature on the major dynamic nonlinear optical processes

ILS-ESP An efficient, simple, and parameter-free algorithm for solving the permutation flow-shop problem

From a managerial point of view, the more effcient, simple, and parameter-free (ESP) an algorithm is, the more likely it will be used in practice for solving real-life problems. Following this principle, an ESP algorithm for solving the Permutation Flowshop Sequencing Problem (PFSP) is proposed in this article. Using an Iterated Local Search (ILS) framework, the so-called ILS-ESP algorithm is able to compete in performance with other well-known ILS-based approaches, which are considered among the most effcient algorithms for the PFSP. However, while other similar approaches still employ several parameters that can affect their performance if not properly chosen, our algorithm does not require any particular fine-tuning process since it uses basic "common sense" rules for the local search, perturbation, and acceptance criterion stages of the ILS metaheuristic. Our approach defines a new operator for the ILS perturbation process, a new acceptance criterion based on extremely simple and transparent rules, and a biased randomization process of the initial solution to randomly generate different alternative initial solutions of similar quality -which is attained by applying a biased randomization to a classical PFSP heuristic. This diversification of the initial solution aims at avoiding poorly designed starting points and, thus, allows the methodology to take advantage of current trends in parallel and distributed computing. A set of extensive tests, based on literature benchmarks, has been carried out in order to validate our algorithm and compare it against other approaches. These tests show that our parameter-free algorithm is able to compete with state-of-the-art metaheuristics for the PFSP. Also, the experiments show that, when using parallel computing, it is possible to improve the top ILS-based metaheuristic by just incorporating to it our biased randomization process with a high-quality pseudo-random number generator.

A Simple Access Pricing Rule to Achieve the Ramsey Outcome in Two-Way Access

In this paper, I consider a general and informationally effcient approach to determine the optimal access rule and show that there exists a simple rule that achieves the Ramsey outcome as the unique equilibrium when networks compete in linear prices without network-based price discrimination. My approach is informationally effcient in the sense that the regulator is required to know only the marginal cost structure, i.e. the marginal cost of making and terminating a call. The approach is general in that access prices can depend not only on the marginal costs but also on the retail prices, which can be observed by consumers and therefore by the regulator as well. In particular, I consider the set of linear access pricing rules which includes any fixed access price, the Efficient Component Pricing Rule (ECPR) and the Modified ECPR as special cases. I show that in this set, there is a unique access rule that achieves the Ramsey outcome as the unique equilibrium as long as there exists at least a mild degree of substitutability among networks' services.

The Simple Economics of Conglomeration with Bankruptcy Costs: Separate or Joint Financing?

Which projects should be financed through separate non-recourse loans (or limited- liability companies) and which should be bundled into a single loan? In the pres- ence of bankruptcy costs, this conglomeration decision trades off the benefit of co- insurance with the cost of risk contamination. This paper characterize this tradeoff for projects with binary returns, depending on the mean, variability, and skewness of returns, the bankruptcy recovery rate, the correlation across projects, the number of projects, and their heterogeneous characteristics. In some cases, separate financing dominates joint financing, even though it increases the interest rate or the probability of bankruptcy.

A simple permutation test for clusteredness

Hierarchical clustering is a popular method for finding structure in multivariate data,resulting in a binary tree constructed on the particular objects of the study, usually samplingunits. The user faces the decision where to cut the binary tree in order to determine the numberof clusters to interpret and there are various ad hoc rules for arriving at a decision. A simplepermutation test is presented that diagnoses whether non-random levels of clustering are presentin the set of objects and, if so, indicates the specific level at which the tree can be cut. The test isvalidated against random matrices to verify the type I error probability and a power study isperformed on data sets with known clusteredness to study the type II error.

Simple models for multi-attribute choice with many alternatives: When it does and does not pay to face tradeoffs with binary attributes

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A simple adaptive procedure leading to correlated equilibrium

We propose a simple adaptive procedure for playing a game. In thisprocedure, players depart from their current play with probabilities thatare proportional to measures of regret for not having used other strategies(these measures are updated every period). It is shown that our adaptiveprocedure guaranties that with probability one, the sample distributionsof play converge to the set of correlated equilibria of the game. Tocompute these regret measures, a player needs to know his payoff functionand the history of play. We also offer a variation where every playerknows only his own realized payoff history (but not his payoff function).