Search results for "correction [final-state interaction]"
showing 7 items of 57 documents
Brachytherapy heterogeneity correction algorithm
2011
El objetivo de este trabajo de investigación es el estudio de la influencia de heterogeneidades de los tejidos en la dosimetría de braquiterapia. En concreto, hemos desarrollado un algoritmo que tiene en cuenta las calcificaciones localizadas dentro de la próstata y corrige la dosis de referencia en agua. Este algoritmo está basado en un modelo analítico y es aplicable a Sistemas de Planificación del Tratamiento (TPS) comerciales. El modelo analítico tiene un fundamento teórico consistente, y se basa en los valores de referencia (caso homogéneo) y en la definición de una longitud efectiva, que transforma el recorrido dentro de la calcificación en distancias mayores. La energía depositada en…
Assessing dye-tracer technique for rill flow velocity measurements
2018
Abstract Rill erosion is considered one of the most important processes affecting soil because of the large amount of soil loss. The rill network acts as sediment source and is able to transport both rill flow-detached particles and those delivered from the interrill areas. Small flow depth in a rill and steep slope values of its bed affect significantly flow hydraulics. When rill flow velocity is measured using a dye-tracing method, the mean velocity is calculated by multiplying the measured surface velocity of the leading edge of the tracer plume by a correction factor. The main uncertainty of the dye-tracing technique stands in the relationship between mean and surface flow velocity. In …
Dangerous relationships : biases in freshwater bioassessment based on observed to expected ratios
2018
Copyright by the Ecological Society of America The ecological assessment of freshwaters is currently primarily based on biological communities and the reference condition approach (RCA). In the RCA, the communities in streams and lakes disturbed by humans are compared with communities in reference conditions with no or minimal anthropogenic influence. The currently favored rationale is using selected community metrics for which the expected values (E) for each site are typically estimated from environmental variables using a predictive model based on the reference data. The proportional differences between the observed values (O) and E are then derived, and the decision rules for status ass…
A Bayesian spatio‐temporal analysis of markets during the Finnish 1860s famine
2022
We develop a Bayesian spatio-temporal model to study pre-industrial grain market integration during the Finnish famine of the 1860s. Our model takes into account several problematic features often present when analysing multiple spatially interdependent time series. For example, compared with the error correction methodology commonly applied in econometrics, our approach allows simultaneous modelling of multiple interdependent time series avoiding cumbersome statistical testing needed to predetermine the market leader as a point of reference. Furthermore, introducing a flexible spatio-temporal structure enables analysing detailed regional and temporal dynamics of the market mechanisms. Appl…
Corrected whole blood biomarkers - the equation of Dill and Costill revisited.
2018
Abstract An exercise bout or a dehydration often causes a reduction in plasma volume, which should be acknowledged when considering the change in biomarkers before and after the plasma changing event. The classic equation from Dill and Costill (1974, J. Appl. Physiol., 37, 247–248) for plasma volume shift is usually utilized in such a case. Although this works well with plasma and serum biomarkers, we argue in this note that this traditional approach gives misleading results in the context of whole blood biomarkers, such as lactate, white cells, and thrombocytes. In this study, we demonstrate that to calculate the change in the total amount of circulating whole blood biomarker, one should u…
Accéder au sens et en donner à la parole : de l'importance des constituants prosodiques dans l'enseignement de l'oral en FLE
2018
Learning a foreign language means being in contact with a new environment of sounds compared to that of the mother tongue. The foreign language teacher must help learners to access these sounds both from a perception and a production point of view. The verbo-tonal method of phonetic correction designed in the 1960s-1970s by Professor Petar Guberina (University of Zagreb) provides teachers with tools to correct learners’ pronunciation. The aim of this article is to present some of the advantages of the VTM for phonetic correction, in particular with regard to prosody by showing how important this is for effective communication. This comes in response to difficulties noted by Polish-speaking …
La non stationnarité dans les séries saisonnières. Application au tourisme tunisien
1998
The purpose of the paper is to specify the nature of the seasonal behaviors of tourist stay demand in Tunisia by using recent tools of monthly time series analysis. The available series (tourist expenditures, prices, guest nights, reception capacities,...) are analyzed with the classical theory of demand and the theory of supply induced demand. Empirical results show that these series are generated by non stationary processes which seasonality is stochastic and deterministic. The extent of the maximum likelihood method proposed by Lee (1992) for monthly data emphasizes unit roots and cointegration relationships at some seasonal frequencies. Error correction models are derived for endogenous…