107 research outputs found

    Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

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    The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

    Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

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    A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

    The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

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    Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

    Overview of the JET results in support to ITER

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    Agricultural environments : characterization, classification and mapping; proceedings of the Rome Workshop on Agro-ecological Characterization and Mapping, 14-18 Apr. 1986

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    Meeting: Workshop on Agro-ecological Characterization, Classification and Mapping, 14-18 Apr. 1986, Roma, ITContains maps in front and back pocket

    Caracterização morfológica de acessos de amendoim: avaliação da sensibilidade de alguns descritores Morphological characterization of peanut genotypes: evaluation of the sensibility of some descriptors

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    Este trabalho teve por objetivo avaliar a sensibilidade de doze descritores morfológicos, utilizados na caracterização dos acessos de amendoim (Arachis hypogaea L.) do banco ativo de germoplasma (BAG) do Instituto Agronômico (IAC), quando aplicados a acessos com pouca variabilidade morfológica, a fim de verificar sua eficácia na descrição em alguns cultivares comercializados no País. Para o germoplasma estudado, adotaram-se os seguintes descritores: dimensões dos folíolos, frutos e sementes; coloração das folhas; hábito de crescimento; pigmentação do ramo e "peg"; profundidade inter-reticular, bico e constrição do fruto; coloração da semente; número de sementes por fruto e pilosidade dos ramos e folhas. Estimando-se a média (Y) com o desvio-padrão de 10% (0,10 Y), observa-se que determinados descritores necessitam ser revistos, para uso descritivo de cultivares, e que mudanças no tamanho das amostras e no número de avaliadores devem ser também levados em consideração. Os descritores mais eficientes foram: hábito de crescimento e dimensão das sementes.<br>The objective of this paper is to evaluate the sensibility of twelve morphological descriptors, used for characterization of peanut access (Arachis hypogaea L.) of the active germplasm bank (BAG) at Instituto Agronômico de Campinas (IAC), State of São Paulo, Brazil, when used for Brazilians cultivars. The results showed that some descriptors need to be modified, in order to be applied as usually done in the "BAG", and changes in the size of plots and the number of valuators must be considered. Changes should be made on the sample size used to estimate leaflet proportions, pilosity, leaf, branch and peg color, pod constriction, reticulation and beak and the seed number. Concerning the same methodology used in that "BAG", the branch habit and seed dimensions were the most efficient descriptors, among those compared in the present paper
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