Experiences in porting mini-applications to OpenACC and OpenMP on heterogeneous systems

This article studies mini-applications—Minisweep, GenASiS, GPP, and FF—that use computational methods commonly encountered in HPC. We have ported these applications to develop OpenACC and OpenMP versions, and evaluated their performance on Titan (Cray XK7 with K20x GPUs), Cori (Cray XC40 with Intel KNL), Summit (IBM AC922 with Volta GPUs), and Cori-GPU (Cray CS-Storm 500NX with Intel Skylake and Volta GPUs). Our goals are for these new ports to be useful to both application and compiler developers, to document and describe the lessons learned and the methodology to create optimized OpenMP and OpenACC versions, and to provide a description of possible migration paths between the two specifications. Cases where specific directives or code patterns result in improved performance for a given architecture are highlighted. We also include discussions of the functionality and maturity of the latest compilers available on the above platforms with respect to OpenACC or OpenMP implementations

THE ECONOMIC FACTORS INFLUENCING PRODUCERS' DEMAND FOR FARM MANAGERS

Results from a Tobit model showed a complementary relationship between marketing inputs and the decision to hire farm managers. According to the results, as farmers increase expenditure on marketing consultants and information systems, their expenditure on farm managers increase as well.Farm Management,

Target Markets for Grain and Cotton Marketing Consultants and Market Information Systems

This paper examines the use of market consultants and market information systems by grain and cotton producers. A model of producer demand for marketing information and consultants is proposed that decomposes price received into exogenous and endogenous components. The analysis is based on a survey of over 1,600 producers. The results suggest that expenditures on market information systems and market consultants are not independent and, more specifically, expenditures on marketing consultants substitute for expenditures on market information systems.expected utility, market information, marketing, risk, Tobit, Marketing,

EXTENSION EDUCATORS' SUPPLY OF RISK MANAGEMENT TRAINING TO FARMERS

A univariate Tobit model of extension educators' provision of risk management educational training was conducted in Mississippi, Texas, Indiana, and Nebraska. A complementary relationship exists between percent of time devoted to agricultural responsibilities and the provision of risk management training courses. The results indicate that, as extension educators perceive farmers to be more knowledgeable of risk management tools, their provision of risk management education decreases. On the other hand, the provision of risk management courses increase as extension educators perceive themselves as being more knowledgeable on the use of risk management tools.Teaching/Communication/Extension/Profession,

Empirismo y derechos humanos. Unas reflexiones a partir de la Filosofía del Derecho de K. Olivecrona

Tomado en serio, el empirismo parece abocar a la negación de los derechos humanos; al menos entendidos como expresión de la naturaleza humana. Bajo esta óptica, K. Olivecrona rechaza explícitamente todo Derecho natural, por considerarlo una noción metafísica. En cambio, cuando describe el Derecho positivo, se encuentra con que éste parece asegurar un determinado orden de valores. Olivecrona, además de describir este dato, en diversos escritos asume dichos valores e incluso los defiende. Esta última postura no es muy coherente con una metodología que niega el conocimiento moral. Seguramente por ello, con el paso del tiempo, Olivecrona va abandonando la defensa de dichos valores e, incluso, marginando su interés por constatarlos empíricamente. El Derecho queda reducido a mera fuerza organizada y monopolizada por el Estado. Pero esta renuncia escamotea otro hecho empírico: la opción general y radical a partir de la segunda Guerra mundial de los modernos sistemas constitucionales por separar ley y derechos, constituyendo a los más básicos como fundamento del orden político y jurídico. A la vista de este fenómeno, pensamos que no sólo es posible explicarlo, sino que incluso se puede justificar, en la medida en que la institucionalización de estos derechos fundamentales no es sólo moralmente debida, sino, de un modo más específico, jurídicamente debida.Seriously taken, empiricism seems to lead to the denial of human rights; at least if they are understood as the expression of human nature. In this optic, K. Olivecrona explicitly rejects any natural law, for being a metaphysical notion. However, when he describes positive law, he finds that it apparently assures a specific set of values. Olivecrona, besides describing this datum, accepts and defends these values in various writings. This last choice is not very coherent with a methodology which denies moral understanding. Probably this is the reason why he gradually abandons the defence of those values and progressively drops his interest in validate them empirically. Law is reduced to a mere organized force monopolized by the State. But this renunciation overlooks another empirical fact: after the Second World War modern constitutional systems have generally and radically opted to separate Law and rights and moreover some of these have been set up as the basis of the political and legal order. In view of this phenomenon, we strongly believe that it is possible to explain it, but even to justify it, considering that the institutionalization of these fundamental rights is based on a specific demand of justice

Dengue una enfermedad emergente y re-emergente en América

El Dengue es una enfermedad infecciosa, producida por un arbovirus cuyo único reservorio es el hombre. El virusutiliza como vector biológico al mosquito Aedes aegypti o al mosquito Aedes albopictus. La sintomatología se presentahabitualmente como un cuadro febril denominado dengue clásico, que se caracteriza por fiebre alta de presentaciónaguda, de duración limitada (2 a 7 días), con intenso malestar general, acompañado de erupción cutánea. Puedepresentar síntomas hemorrágicos de escasa intensidad, como petequias y sangramiento gingival. El tratamiento essintomático y el paciente mejora completamente en aproximadamente 7 días. Esta forma de dengue no producemortalidad. Sin embargo, existen otras presentaciones de la enfermedad que pueden llegar a manifestaciones graves deltipo hemorrágicas con muerte, lo que se presenta en el 5% de los enfermos. El dengue es un problema creciente desalud pública, que afecta a más de 100 países en el mundo, con más de 50 millones de casos informados cada año. Loscuatro tipos de dengue, están circulando en América, donde los casos aumentaron en los últimos años en formaexplosiva. Si bien, en Chile continental no se ha documentado la existencia del mosquito vector del dengue de formaendémica, si se ha hecho en Chile Insular, más específicamente en Isla de Pascua, donde desde el año 1999, seincorporó a la lista de enfermedades de declaración obligatoria (D.S. Nº 158) estableciendo su vigilancia. Los factoresque han llevado a la emergencia de esta enfermedad son principalmente el cambio climático, que ha modificado elnicho ecológico de los mosquitos de la familia Aedes. También la urbanización, la falta de control del vector, las fallasen infraestructura básica y el pobre saneamiento ambiental. La intervención primaria de salud pública ha ido por la líneadel uso de insecticidas para el control del vector y la detección temprana de casos. No existe aún una vacuna efectiva,sin embargo, actualmente se están realizando esfuerzos en esta materia

Análisis cepstral y la transformada de Hilbert-Huang para la detección automática de la enfermedad de Parkinson

Most patients with Parkinson’s Disease (PD) develop speech deficits, including reduced sonority, altered articulation, and abnormal prosody. This article presents a methodology to automatically classify patients with PD and Healthy Control (HC) subjects. In this study, the Hilbert-Huang Transform (HHT) and Mel-Frequency Cepstral Coefficients (MFCCs) were considered to model modulated phonations (changing the tone from low to high and vice versa) of the vowels /a/, /i/, and /u/. The HHT was used to extract the first two formants from audio signals with the aim of modeling the stability of the tongue while the speakers were producing modulated vowels. Kruskal-Wallis statistical tests were used to eliminate redundant and non-relevant features in order to improve classification accuracy. PD patients and HC subjects were automatically classified using a Radial Basis Support Vector Machine (RBF-SVM). The results show that the proposed approach allows an automatic discrimination between PD and HC subjects with accuracies of up to 75 % for women and 73 % for men.La mayoría de las personas con la enfermedad de Parkinson (EP) desarrollan varios déficits del habla, incluyendo sonoridad reducida, alteración de la articulación y prosodia anormal. Este artículo presenta una metodología que permite la clasificación automática de pacientes con EP y sujetos de control sanos (CS). Se considera que la transformada de Hilbert-Huang (THH) y los Coeficientes Cepstrales en las frecuencias de Mel modelan las fonaciones moduladas (cambiando el tono de bajo a alto y de alto a bajo) de las vocales /a/, /i/, y /u/. La THH se utiliza para extraer los dos primeros formantes de las señales de audio, con el objetivo de modelar la estabilidad de la lengua mientras los hablantes producen vocales moduladas. Pruebas estadísticas de Kruskal-Wallis se utilizan para eliminar características redundantes y no relevantes, con el fin de mejorar la precisión de la clasificación. La clasificación automática de sujetos con EP vs. CS se realiza mediante una máquina de soporte vectorial de base radial. De acuerdo con los resultados, el enfoque propuesto permite la discriminación automática de sujetos con EP vs. CS con precisiones de hasta el 75 % para los hombres y 73 % para las mujeres

A forced thermal ratchet in a memory heat bath

The present work studies a non-Markovian forced thermal ratchet model on an asymmetric periodic potential. The Brownian dynamics is described by a generalized Langevin equation with an Ornstein-Uhlenbeck-type friction memory kernel. We show that for the case of a time-dependent driving force, also in the form of an Ornstein-Uhlenbeck-like process, an exact expression of the probability current can be derived. We also obtain the behavior of the particle's average rate of flow as a function of the external amplitude force and of the bath temperature when the driving force behaves as a square wave modulation. All our results are compared with those obtained in the Markovian case and we find, fairly remarkably, that in some cases a friction memory kernel results in an enhancement of the curren

Carnot, Stirling, Ericsson stochastic heat engines: Efficiency at maximum power

This work obtains the efficiency at maximum power for a stochastic heat engine performing Carnot-like, Stirling-like and Ericsson-like cycles. For the mesoscopic engine a Brownian particle trapped by an optical tweezers is considered. The dynamics of this stochastic engine is described as an overdamped Langevin equation with a harmonic potential, whereas is in contact with two thermal baths at different temperatures, namely, hot ($T_h$) and cold ($T_c$). The harmonic oscillator Langevin equation is transformed into a macroscopic equation associated with the mean value $\langle x^2(t)\rangle$ using the original Langevin approach. At equilibrium stationary state this quantity satisfies a state-like equation from which the thermodynamic properties are calculated. To obtained the efficiency at maximum power it is considered the finite-time cycle processes under the framework of low dissipation approach.Comment: 2 3pages, 5 figure