Improved equilibrium reconstructions by advanced statistical weighting of the internal magnetic measurements.

Rev Sci Instrum

Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, EURATOM Association, Wendelsteinstr.1, 17491 Greifswald, Germany.

Published: December 2014

In a Tokamak the configuration of the magnetic fields remains the key element to improve performance and to maximise the scientific exploitation of the device. On the other hand, the quality of the reconstructed fields depends crucially on the measurements available. Traditionally in the least square minimisation phase of the algorithms, used to obtain the magnetic field topology, all the diagnostics are given the same weights, a part from a corrective factor taking into account the error bars. This assumption unduly penalises complex diagnostics, such as polarimetry, which have a limited number of highly significant measurements. A completely new method to choose the weights, to be given to the internal measurements of the magnetic fields for improved equilibrium reconstructions, is presented in this paper. The approach is based on various statistical indicators applied to the residuals, the difference between the actual measurements and their estimates from the reconstructed equilibrium. The potential of the method is exemplified using the measurements of the Faraday rotation derived from JET polarimeter. The results indicate quite clearly that the weights have to be determined carefully, since the inappropriate choice can have significant repercussions on the quality of the magnetic reconstruction both in the edge and in the core. These results confirm the limitations of the assumption that all the diagnostics have to be given the same weight, irrespective of the number of measurements they provide and the region of the plasma they probe.

Download full-text PDF

Source
http://dx.doi.org/10.1063/1.4904450DOI Listing

Publication Analysis

Top Keywords

improved equilibrium
8
equilibrium reconstructions
8
magnetic fields
8
measurements
7
magnetic
5
reconstructions advanced
4
advanced statistical
4
statistical weighting
4
weighting internal
4
internal magnetic
4

Similar Publications

Background: The growth of telehealth care delivery during the COVID-19 pandemic highlighted its potential to enhance access to care and improve patient outcomes. As the healthcare landscape moves toward a new equilibrium in care delivery, few studies have examined physician usage of specific telehealth modalities.

Objective: To understand telehealth usage differences among modalities and across subgroups of physicians.

View Article and Find Full Text PDF

Cell-free systems are powerful synthetic biology technologies that can recapitulate gene expression and sensing without the complications of living cells. Cell-free systems can perform more advanced functions when genetic circuits are incorporated. Here we expand cell-free biosensing by engineering a highly specific isothermal amplification circuit called polymerase strand recycling (PSR), which leverages T7 RNA polymerase off-target transcription to recycle nucleic acid inputs within DNA strand displacement circuits.

View Article and Find Full Text PDF

RNA recognition motifs (RRMs) are a key class of proteins that primarily bind single-stranded RNAs. In this study, we applied standard atomistic molecular dynamics simulations to obtain insights into the intricate binding dynamics between uridine-rich RNAs and TbRGG2 RRM using the recently developed OL3-Stafix AMBER force field, which improves the description of single-stranded RNA molecules. Complementing structural experiments that unveil a primary binding mode with a single uridine bound, our simulations uncover two supplementary binding modes in which adjacent nucleotides encroach upon the binding pocket.

View Article and Find Full Text PDF

Introduction:  Research on the association between blood groups and cardiovascular diseases (CVDs) in Africa, including Algeria, is notably limited, with a primary focus on blood donors. This narrow scope hinders a comprehensive understanding of the genetic diversity of blood groups and their potential links to CVD risk within the African context. To bridge this knowledge gap, this study proposes to investigate the distribution of blood group genotypes and their association with CVD prevalence, aiming to enhance knowledge within the African context and contribute to global insights into the relationship between blood groups and CVD.

View Article and Find Full Text PDF

Tenofovir alafenamide (TAF) is currently administered orally to patients for treatment of chronic hepatitis B virus infection and as a part of a combination therapy for human immunodeficiency virus (HIV) infection. A long-acting delivery system could provide several advantages as a formulation strategy for this drug including improved patient adherence, convenience, more consistent drug levels and potentially fewer side effects. To date, the vast majority of polymer-based long-acting delivery systems have been prepared from poly(lactide--glycolide) [1].

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!