Deconvolução de perfis de poços através do ajuste de energia

As medidas de resistividade são de fundamental importância para o cálculo da saturação de óleo em reservatórios potencialmente produtores. A combinação das medidas de resistividade rasa e profunda permite a obtenção dos parâmetros R_t, R_xo e d_i. Mas, em reservatórios complexos existem dificuldades em se obter leituras confiáveis de R_t, devido à baixa resolução vertical das ferramentas de investigação profunda. Em reservatórios laminados, por exemplo, as leituras obtidas pela ferramenta de indução profunda (ILD) podem levar a uma interpretação errônea das mesmas, levando a acreditar que as medidas obtidas do perfil referem-se a uma única camada. Este problema pode ser em parte resolvido através de uma metodologia que melhore a resolução vertical dos perfis de investigação profunda, valendo-se do uso de informações obtidas de um perfil de alta resolução vertical, i.e; a curva de resistividade rasa. Uma abordagem neste sentido seria usar um perfil de alta resolução que apresente uma boa correlação com o perfil de investigação profunda. Esta correlação pode ser melhor avaliada se aplicarmos um filtro no perfil de alta resolução, de tal forma que o perfil resultante tenha teoricamente a mesma resolução vertical do perfil de baixa resolução. A obtenção deste filtro, porém, recai na premissa de que as funções respostas verticais para as ferramentas de alta e baixa resolução são disponíveis, o que não ocorre na prática. Este trabalho se propõe mostrar uma nova abordagem onde o filtro pode ser obtido a partir de um tratamento no domínio da freqüência. Tal tratamento visa igualar a energia espectral do perfil de alta resolução à energia espectral do perfil de baixa resolução tendo como base o Teorema de Parseval. Será mostrado que a resolução vertical depende fundamentalmente da energia espectral do perfil em questão. A seguir, uma regressão linear é aplicada sobre os perfis de alta resolução filtrado e de baixa resolução. Para cada ponto amostrado dos perfis, uma rotina de minimização é aplicada visando escolher o melhor intervalo de correlação entre os perfis. Finalmente, um fator de correção é aplicado sobre cada ponto do perfil de baixa resolução. Os resultados obtidos com os perfis de indução são promissores, demonstrando a eficácia da abordagem e mesmo quando aplicada em perfis com diferentes propriedades petrofísicas, a metodologia funcionou satisfatoriamente, sem danificar os perfis originais.

Registro de lectura : Dispositivo pedagógico que acompaña trayectorias formativas universitarias

El siguiente trabajo se enmarca en la línea de investigación sobre formación docente en Educación Física, desarrollada en el Centro Regional Universitario Bariloche de la Universidad Nacional del Comahue (CRUB-UNCo). Los proyectos que la integran, a partir del incremento sostenido del número de estudiantes que abandonan la carrera durante los dos primeros años, procuran interrogar las prácticas pedagógicas universitarias en ese campo, desentrañar sus modos particulares de producción y analizar su impacto en la constitución de los trayectos formativos de los y las estudiantes. En las indagaciones hallamos indicios de un trabajo docente sistemático para mejorar las condiciones de la enseñanza y del aprendizaje e identificamos dispositivos pedagógicos institucionales y áulicos a modo de andamiaje de las trayectorias estudiantiles y modos de recepción a los y las ingresantes. En esta oportunidad describimos y analizamos uno de estos dispositivos, denominado "registro de lectura", generado en la cátedra Pedagogía del 1º año del Profesorado en Educación Física del mencionado centro universitario. Dicho instrumento forma parte de una serie de prácticas pedagógicas deliberadamente planificadas en relación con el ingreso, la permanencia y el egreso del nivel superior, que pretende habilitar mejores escenarios para el desarrollo de los procesos educativos. El dispositivo, construido a modo de andamiaje de las prácticas lectoras de los y las estudiantes, pretende contribuir a la promoción de trayectorias formativas democráticas y procura dar lugar a nuevas explicaciones en tanto anclajes para la transformación y para la construcción de nuevos conocimientos así como lograr mejores intervenciones pedagógicas

Registro de lectura : Dispositivo pedagógico que acompaña trayectorias formativas universitarias

El siguiente trabajo se enmarca en la línea de investigación sobre formación docente en Educación Física, desarrollada en el Centro Regional Universitario Bariloche de la Universidad Nacional del Comahue (CRUB-UNCo). Los proyectos que la integran, a partir del incremento sostenido del número de estudiantes que abandonan la carrera durante los dos primeros años, procuran interrogar las prácticas pedagógicas universitarias en ese campo, desentrañar sus modos particulares de producción y analizar su impacto en la constitución de los trayectos formativos de los y las estudiantes. En las indagaciones hallamos indicios de un trabajo docente sistemático para mejorar las condiciones de la enseñanza y del aprendizaje e identificamos dispositivos pedagógicos institucionales y áulicos a modo de andamiaje de las trayectorias estudiantiles y modos de recepción a los y las ingresantes. En esta oportunidad describimos y analizamos uno de estos dispositivos, denominado "registro de lectura", generado en la cátedra Pedagogía del 1º año del Profesorado en Educación Física del mencionado centro universitario. Dicho instrumento forma parte de una serie de prácticas pedagógicas deliberadamente planificadas en relación con el ingreso, la permanencia y el egreso del nivel superior, que pretende habilitar mejores escenarios para el desarrollo de los procesos educativos. El dispositivo, construido a modo de andamiaje de las prácticas lectoras de los y las estudiantes, pretende contribuir a la promoción de trayectorias formativas democráticas y procura dar lugar a nuevas explicaciones en tanto anclajes para la transformación y para la construcción de nuevos conocimientos así como lograr mejores intervenciones pedagógicas

Registro de lectura : Dispositivo pedagógico que acompaña trayectorias formativas universitarias

El siguiente trabajo se enmarca en la línea de investigación sobre formación docente en Educación Física, desarrollada en el Centro Regional Universitario Bariloche de la Universidad Nacional del Comahue (CRUB-UNCo). Los proyectos que la integran, a partir del incremento sostenido del número de estudiantes que abandonan la carrera durante los dos primeros años, procuran interrogar las prácticas pedagógicas universitarias en ese campo, desentrañar sus modos particulares de producción y analizar su impacto en la constitución de los trayectos formativos de los y las estudiantes. En las indagaciones hallamos indicios de un trabajo docente sistemático para mejorar las condiciones de la enseñanza y del aprendizaje e identificamos dispositivos pedagógicos institucionales y áulicos a modo de andamiaje de las trayectorias estudiantiles y modos de recepción a los y las ingresantes. En esta oportunidad describimos y analizamos uno de estos dispositivos, denominado "registro de lectura", generado en la cátedra Pedagogía del 1º año del Profesorado en Educación Física del mencionado centro universitario. Dicho instrumento forma parte de una serie de prácticas pedagógicas deliberadamente planificadas en relación con el ingreso, la permanencia y el egreso del nivel superior, que pretende habilitar mejores escenarios para el desarrollo de los procesos educativos. El dispositivo, construido a modo de andamiaje de las prácticas lectoras de los y las estudiantes, pretende contribuir a la promoción de trayectorias formativas democráticas y procura dar lugar a nuevas explicaciones en tanto anclajes para la transformación y para la construcción de nuevos conocimientos así como lograr mejores intervenciones pedagógicas

Invariance levels across language versions of the PISA 2009 reading comprehension tests in Spain

Resumen tomado de la publicaci??n

Prediction leaching of potassium using the convective-dispersive and the convective log-normal transfer function models

There is increasing concern about soil enrichment with K+ and subsequent potential losses following long-term application of poor quality water to agricultural land. Different models are increasingly being used for predicting or analyzing water flow and chemical transport in soils and groundwater. The convective-dispersive equation (CDE) and the convective log-normal transfer function (CLT) models were fitted to the potassium (K+) leaching data. The CDE and CLT models produced equivalent goodness of fit. Simulated breakthrough curves for a range of CaCl2 concentration based on parameters of 15 mmol l(-1) CaCl2 were characterised by an early peak position associated with higher K+ concentration as the CaCl2 concentration used in leaching experiments decreased. In another method, the parameters estimated from 15 mmol l(-1) CaCl2 solution were used for all other CaCl2 concentrations, and the best value of retardation factor (R) was optimised for each data set. A better prediction was found. With decreasing CaCl2 concentration the value of R is required to be more than that measured (except for 10 mmol l(-1) CaCl2), if the estimated parameters of 15 mmol l(-1) CaCl2 are used. The two models suffer from the fact that they need to be calibrated against a data set, and some of their parameters are not measurable and cannot be determined independently.

Linkage disequilibrium assessment via log-linear modeling of SNP haplotype frequencies

Analyses of high-density single-nucleotide polymorphism (SNP) data, such as genetic mapping and linkage disequilibrium (LD) studies, require phase-known haplotypes to allow for the correlation between tightly linked loci. However, current SNP genotyping technology cannot determine phase, which must be inferred statistically. In this paper, we present a new Bayesian Markov chain Monte Carlo (MCMC) algorithm for population haplotype frequency estimation, particulary in the context of LD assessment. The novel feature of the method is the incorporation of a log-linear prior model for population haplotype frequencies. We present simulations to suggest that 1) the log-linear prior model is more appropriate than the standard coalescent process in the presence of recombination (>0.02cM between adjacent loci), and 2) there is substantial inflation in measures of LD obtained by a "two-stage" approach to the analysis by treating the "best" haplotype configuration as correct, without regard to uncertainty in the recombination process. Genet Epidemiol 25:106-114, 2003. (C) 2003 Wiley-Liss, Inc.

The role of the log transformation in forecasting economic variables

For forecasting and economic analysis many variables are used in logarithms (logs). In time series analysis, this transformation is often considered to stabilize the variance of a series. We investigate under which conditions taking logs is beneficial for forecasting. Forecasts based on the original series are compared to forecasts based on logs. For a range of economic variables, substantial forecasting improvements from taking logs are found if the log transformation actually stabilizes the variance of the underlying series. Using logs can be damaging for the forecast precision if a stable variance is not achieved.

Linear vs. log-linear unit-root specification: an application of mis-specification encompassing

The objective of this paper is to apply the mis-specification (M-S) encompassing perspective to the problem of choosing between linear and log-linear unit-root models. A simple M-S encompassing test, based on an auxiliary regression stemming from the conditional second moment, is proposed and its empirical size and power are investigated using Monte Carlo simulations. It is shown that by focusing on the conditional process the sampling distributions of the relevant statistics are well behaved under both the null and alternative hypotheses. The proposed M-S encompassing test is illustrated using US total disposable income quarterly data.

Effects of yellow filters on visual acuity, contrast sensitivity and reading under conditions of forward light scatter

Background Yellow filters are sometimes recommended to people with low vision. Our aim was investigate the effects of three commercial yellow filters on visual acuity and contrast sensitivity (with and without glare) and reading (without glare) under conditions of forward light scatter (FLS). Method Fifty-five healthy subjects were assessed with Corning Photochromic Filters (CPFs) 450, 511 and 527 and a filter producing FLS. The effects on log MAR visual acuity, Pelli–Robson contrast sensitivity with and without glare, and reading (measured with MNRead charts) without glare were determined. Results Statistically significant differences were found between the overall effect of glare and between CPFs for visual acuity and contrast sensitivity. A gradual decline in visual acuity, contrast sensitivity and reading with increasing CPF absorption was noted. Conclusion Effects of CPF450, 511, 527 on visual acuity, contrast sensitivity and reading under conditions of FLS were negative but not clinically significant.

The ILC's Articles on Responsibility of States for Internationally Wrongful Acts: Completion of the Second Reading

In 2001 the International Law Commission finally adopted on second reading the Draft Articles on Responsibility of States for Internationally Wrongful Acts with commentaries, bringing to an end nearly 50 years of ILC work on the subject. This article reviews the final group of changes to the text, focusing on the definitions of ‘injury’ and ‘damage’, assurances of non‐repetition in the light of the LaGrand case, procedural aspects of countermeasures and the controversy over measures taken in response to a breach by states which are not individually injured. The focus of debate now turns to the UNGA Sixth Committee, which will have to decide what to make of the Draft Articles. The ILC itself recommended an initial resolution taking note of the Articles, with subsequent consideration (after a period of years) of a possible diplomatic conference with a view to concluding a convention. This modest proposal allows for further reflection on the text and may help to avoid possibly divisive and inconclusive debate in the Sixth Committee. At the same time it allows time for better understanding of the many changes made as compared with the first reading text (1996).

Encounters and content sharing in an urban village : reading texts through an archaeological lens

Archaeology provides a framework of analysis and interpretation that is useful for disentangling the textual layers of a contemporary lived-in urban space. The producers and readers of texts may include those who planned and developed the site and those who now live, visit and work there. Some of the social encounters and content sharing between these people may be artificially produced or manufactured in the hope that certain social situations will occur. Others may be serendipitous. With archaeology’s original focus on places that are no longer inhabited it is often only the remaining artefacts and features of the built environment that form the basis for interpreting the social relationships of past people. Our analysis however, is framed within a contemporary notion of archaeological artefacts in an urban setting. Unlike an excavation, where the past is revealed through digging into the landscape, the application of landscape archaeology within a present day urban context is necessarily more experiential, visual and based on recording and analysing the physical traces of social encounters and relationships between residents and visitors. These physical traces are present within the creative content, and the built and natural elements of the environment. This chapter explores notions of social encounters and content sharing in an urban village by analysing three different types of texts: the design of the built environment; content produced by residents through a geospatial web application; and, print and online media produced in digital storytelling workshops.