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• Unique 0.1 mm/pixel IR thermography diagnostic for plasma-wall interaction studies. • Improved accuracy and reliability on field of view positioning. • Operational on WEST tokamak since 2020. • Diagnostic is accurate to the monoblock. The Very High spatial Resolution (VHR) infrared thermography diagnostic developed by CEA-IRFM is installed in the WEST tokamak to measure surface temperature of the actively cooled W-monoblocks (MB) of the Plasma Facing Units (PFUs), which are similar to the International Thermonuclear Experimental Reactor (ITER) ones. It is a major diagnostic to investigate the behavior of PFU during experimentation thanks to its very high spatial resolution (0.1 mm / pixel), movable field of view (FoV) and the wide-range temperature measurement. In particular, it can study the evolution of monoblocks mounted in the tokamak, the influence of the shaping of these components submitted to high heat load and the behavior of the leading edges regarding the assembling tolerances between adjacent monoblocks. Finally, such diagnostic directly contributes to the specification assessment of the ITER divertor units. This diagnostic was operational during the 2019 WEST experimentation and its enhanced design for the 2020 WEST experimentation campaign. In order to monitor 30 × 12 mm monoblocks temperature, the VHR IR diagnostic is able to move its narrow FoV (64 × 51 mm) to specific targets on the observable divertor area (360 × 420 mm). Position and focus steering are achieved through motor-controlled mirrors and lenses operated by a dedicated Labview application on a remote unit. Mirror positioning occurs between pulses under normal WEST operation conditions, and can withstand thermal radiation and disruptions during pulses. Repeatability, hysteresis, mechanical components reliability are critical parameters to provide accurate positioning (<1 mm) of the FoV. The tuning and calibration of these actuators in accordance with WEST environment is crucial to guarantee the best position of the FoV and optical performances. This paper gives the FoV positioning implementation details and performance of the VHR in WEST. [ABSTRACT FROM AUTHOR]

Objective: To retrospectively compare semi-automated and manual volume measurements of malignant liver tumours and inter- and intra-observer variability using commercially available software.Methods: This study was performed on 60 consecutive patients with untreated liver metastases (30) and HCCs (30), i.e. 92 lesions (49 metastases, 43 HCCs) using hepatic MDCT. Lesion volumes were manually measured independently by two radiologists and semi-automatically by the same two radiologists and a technician. Those measurements were repeated on 20 patients (10 metastases and 10 HCCs) a week later. An independent operator timed all the measurements. Using the Spearman correlation coefficient and Bland-Altman plots, statistical analyses were performed.Results: Liver lesion volumes obtained with semi-automated and manual methods were well correlated (Spearman, r = 0.98 and 0.91). Their agreement was high for intra-observer measurements with the semi-automated method (Spearman, r = 0.91 and 0.94). The agreement was lower for inter-observer measurements with both methods (Spearman, r = 0.87 for semi-automated and 0.91 for manual). The semi-automated method significantly reduced the post-processing duration (23s ± 19s vs. 33s ± 11s, p value <0.0001).Conclusion: In our study, semi-automated volume analysis of malignant liver tumours correlated well with the manual method. Furthermore, the semi-automated volume analysis was significantly quicker. [ABSTRACT FROM AUTHOR]

The observed and simulated low-frequency winter variability of the North Atlantic and European region is investigated based on the climate regimes paradigm. Empirical orthogonal functions and cluster analyses are used to describe the variability of monthly mean sea level pressure over the 1958–2001 period, both in the European Centre for Medium-Range Weather Forecasts (ECMWF) 40-yr reanalysis (ERA40) data set and the multi-model ensemble hindcasts from the DEMETER seasonal forecasting system.The clustering partition of ERA40 fields yields four climate regimes. The first two clusters capture the negative and positive phases of the North Atlantic Oscillation (NAO), respectively. The third and fourth clusters, respectively, display a strong anticyclonic ridge off western Europe almost covering the entire basin and a zonal pressure dipole between Greenland and Scandinavia, with a clear south-eastward extension of the low-pressure anomalies towards the Iberian peninsula.DEMETER seasonal forecasting models are able to reproduce the multimodal variability of the winter atmosphere with the same number of modes. For the ECMWF model, the pressure patterns of the regimes are very similar to those obtained for ERA40. For the six other models, the two NAO modes are well reproduced but the two other regimes are more different. In terms of forecasts, different scoring methods are used to evaluate the ability of the models to predict the correct regimes for a given date, but scores appear to be quite low.Then, the link between the pressure regimes and the corresponding temperature fields is investigated using different composite methods. All the ERA40 regimes are characterized by specific patterns of temperature. DEMETER models are also able to reproduce the temperature impacts of the different regimes. Thus, some predictability could arise from reliable seasonal predictions. Indeed, if models are able to forecast pressure fields at a monthly time-scale, it should allow us to forecast which regime will be excited and then to deduce the corresponding large-scale pattern of temperature anomalies. [ABSTRACT FROM AUTHOR]

• C++ framework for offline/real-time visualization and processing of multi-sensor data. • Thermavip is used for firm real-time machine control and offline physical studies. • Thermavip provides a SDK and a plugin mechanism for porting to any fusion devices. • Widely used on WEST and EAST tokamaks, W7-X stellarator and HADES facility. • Strong emphasis on video data (IR/VIS), provides a full-featured video annotation tool. In current tokamaks, imaging diagnostics (visible/infrared) have become increasingly used for real-time control of the temperature of the Plasma Facing Components (PFC) and for off-line physical analysis. Developing a full acquisition and control system based on a network of multiple cameras is a complex task requiring advanced software tools. Furthermore, such systems produce a large quantity of data encouraging end users to share tools and codes for data access and analysis. In this paper, we introduce a software platform, named Thermavip, dedicated to these tasks. The main contribution of this software is to gather under the same framework different functionalities for (1) firm real-time video acquisition and PFC monitoring, (2) offline data access and display, (3) signal and video processing applied to plasma physics, (4) video annotation and thermal events database management. This software platform is widely used on the WEST (W Environment in S teady-state Tokamak) tokamak (France) for offline study of infrared (IR) and almost all WEST diagnostics data, and online display of IR videos and temperature time traces for critical components. Thermavip platform is also used on the HADES (H igh he A t Loa D tESt) facility (France) and the EAST (Experimental Advanced Superconducting Tokamak) tokamak (China) for offline signal analysis, and on the Wendelstein 7-X (W7-X) stellarator (Germany) for the IR diagnostic acquisition, PFC real-time (RT) monitoring, online display and offline video analysis. In addition, Thermavip provides a full featured video annotation tool used on both WEST and W7-X to build and manage thermal events datasets. These annotations are used as input dataset to train deep-learning models, like Region Based Convolutional Neural Networks, for automatic detection and classification of thermal events based on IR movies. The Thermavip framework is composed of a unique C++ Software Development Kit (SDK) providing high-level classes for offline multi-sensor data analysis, firm real-time processing and online visualization of these sensor data. Its strength comes from its unique component block architecture, allowing to build multicore and distributed processing pipelines for both offline and firm real-time applications. Thermavip architecture relies on a versatile plugin mechanism to extend its functionalities using C++ code or Python scripts, facilitating the integration on new machines. [ABSTRACT FROM AUTHOR]

This paper presents the method toward quantifying the global uncertainty on the blackbody temperature measurement from the infrared (IR) diagnostics of WEST. To address this goal, the main functional elements of the IR diagnostics are identified. Then the temperature calibration and calculation principles are presented and analysed to extract the main potential uncertainty contributors, such as the optical transmission coefficients and their stray lights, or the accuracy of temperature references used for calibration. These contributors are individually estimated, or experimentally measured when a supposed effect on the overall uncertainty is identified, like environmental conditions or parasitic radiations. In particular, effects of environmental temperature on the transmission lines and camera is thoroughly studied. All contributions are then aggregated in the uncertainty propagation calculation and results in an overall temperature uncertainty versus the temperature estimation. The uncertainty is in the range of 5–10% for blackbody temperatures above 200 °C, and progressively worsens when temperature decreases. [ABSTRACT FROM AUTHOR]

Climate simulations consistently show an increase in European near-surface air temperature by the late 21st century, although projections for near-surface wind speeds and irradiance differ between models, and are accompanied by large natural variability. These factors make it difficult to estimate the effects of physical climate change on power system planning. Here, the impact of climate change on future European power systems is estimated. We show for the first time how a set of divergent future power system scenarios lead to marked differences in Europe's total energy balance (demand-net-renewable supply) by 2050, which dominate over the uncertainty associated with climate change (∼50% and ∼5% respectively). However, within any given power system scenario, national power systems may be subject to considerable impacts from climate change, particularly for seasonal differences between renewable resources (e.g., wind power may be impacted by ∼20% or more). There is little agreement between climate models in terms of the spatio-temporal pattern of these impacts, and even in the direction of change for wind and solar. More thorough consideration of climate uncertainty is therefore needed, as it is likely to be of great importance for robust future power system planning and design. • Future climate affects European power systems simulated with EURO-CORDEX models. • Significant climate uncertainty in key power system properties (demand, renewables). • Climate uncertainty exacerbated in renewable-intensive power system scenarios. • Spatio-temporal and multi-model aggregation masks complex patterns of change. • Better understanding of climate uncertainty in power system design is needed. [ABSTRACT FROM AUTHOR]

Twelve ITER-like plasma-facing units made of tungsten were exposed in the WEST tokamak divertor, with three plasma-facing units (PFUs) significantly overexposed to plasma heat flux: one sharp-edged PFU (vertical misalignment h = 0.8 mm) and two chamfered PFUs (h =0.6 mm and 0.3 mm, respectively). This paper describes the first temperature analysis obtained with a very high spatial resolution infrared camera (pixel size ∼ 0.1 mm) on the misaligned PFU edges and shows the consistency obtained on the parallel heat flux derived from these measurements. The analysis is focused on the hottest areas of the PFU misaligned leading edges, since the temperature detection threshold of the VHR camera is high (Tthreshold,BB ≈ 370 °C). The heat flux parallel to the magnetic field lines is assessed by matching the toroidal temperature profile in the vicinity of the leading edge with 3D finite element modelling. The tungsten emissivity assumed in this study is 0.6, which is consistent with laboratory measurements for damaged PFUs. For the three PFUs studied (with different vertical misalignments, incident angles, geometries), the derived parallel heat flux is similar, and consistent with independent measurements by a Fiber Bragg grating embedded in a graphite PFU at another toroidal location, giving confidence in future experiments using the same settings. [ABSTRACT FROM AUTHOR]

A tangential infrared thermography system is installed in the WEST tokamak to observe the thermal scene of the first wall and the divertor components through a wide-angle tangential view. The goal is to provide and monitor the heat load deposition on the plasma facing components. About one-sixth of the chamber is observed, including sectors of the baffle, the lower and upper divertors, one inner bumper, vertical displacement event (VDE) protections, one ICRH antenna, and other parts of the wall. It is used for real time machine protection by monitoring temperature thresholds in delimited region of interest, and for analysis of normal or specific heat load events during operation such as VDE, ELM, disruption or runaways. This wide-angle view uses one aspherical and one on-axis plane mirrors, a sapphire window and three lenses for the objective of the camera. The optical line is optimized for two wavelengths 1.7 and 4 µm. The field of view is 60° on a 512×640 pixels Focal Plane Array. The endoscope is fully actively cooled. The thermal scene is complex to interpret given the fully metallic and radiative environment and the uncertainties on the emissivity which is angular-dependent and changes with the surface properties. This involves significant inaccuracy on the recovery of the real temperature. In this context, an interpretation by modeling approach is better suited, based on ray-tracing simulations taking into account the optical properties of materials. For instance, this allowed discriminating reflections patterns from real thermal events in the wide-angle view. A description of the wide-angle infrared diagnostic and its performances is presented as well as experimental measurements obtained in the WEST Tokamak. [ABSTRACT FROM AUTHOR]

The emotional content of health care professionals-cancer patient communication is often considered as poor and has to be improved by an enhancement of health care professionals empathy. One hundred and fifteen oncology nurses participating in a communication skills training workshop were assessed at three different periods. Nurses randomly allocated to a control group arm (waiting list) were assessed a first time and then 3 and 6 months later. Nurses allocated to the training group were assessed before training workshop, just after and 3 months later. Each nurse completed a 20-min clinical and simulated interview. Each interview was analysed by three content analysis systems: two computer-supported content analysis of emotional words, the Harvard Third Psychosocial Dictionary and the Martindale Regressive Imagery Dictionary and an observer rating system of utterances emotional depth level, the Cancer Research Campaign Workshop Evaluation Manual. The results show that in clinical interviews there is an increased use of emotional words by health care professionals right after having been trained (P=0.056): training group subjects use 4.3 (std: 3.7) emotional words per 1000 used before training workshop, and 7.0 (std: 5.8) right after training workshop and 5.9 (std: 4.3) 3 months later compared to control group subjects which use 4.5 (std: 4.8) emotional words at the first assessment point, 4.3 (std: 4.1) at the second and 4.4 (std: 3.3) at the third. The same trend is noticeable for emotional words used by health care professionals in simulated interviews (P=0.000). The emotional words registry used by health care professionals however remains stable over time in clinical interviews (P=0.141) and is enlarged in simulated interviews (P=0.041). This increased use of emotional words by trained health care professionals facilitates cancer patient emotion words expressions compared to untrained health care professionals especially 3 months after training (P=0.005). This study shows that health care professionals empathy may be improved by communication skills training workshop and that this improvement facilitates cancer patients emotions expression. [ABSTRACT FROM AUTHOR]

During the 2019 experimental campaign, the WEST tokamak was partially equipped with ITER-like plasma facing units (PFUs) made of discrete monoblocks (MBs) in one of the twelve lower divertor sectors. The magnetic field lines can enter the gaps between two MBs and strike their leading edges (LEs) with near normal incidence, leading to high localized heat flux, temperature and thermomechanical stress during both stead-state operation and transients. Exposed leading edges are a particular matter of concern because of potential crack formation, recrystallization or even melting of tungsten. During the 2019 experimental campaign in WEST, five of them were misaligned (vertical misalignment h = 0.30 ± 0.1 mm) with their poloidal leading edges exposed to the plasma heat flux. A medium wavelength IR filter (MWIR: 3.9 ± 0.1 μm) was installed in the very high resolution infrared system, featuring a submillimeter spatial resolution (∼0.1 mm/pixel). This system has a temperature detection threshold of T threshold, BB ≈ 250 °C. In this paper, thermal analysis will be presented with a specific focus on overheating of poloidal and toroidal edges using post-mortem measured emissivity maps. The study reveals an unexpected hot spot in the top LE corner of misaligned PFUs at the outer strike point (OSP). Photonic calculations were performed with different emissivity on top and lateral surfaces, in order to consider the complex reflectance characteristics in the toroidal gaps. During this experiment, the Larmor radius (0.35 mm) is comparable to the gap size. Thus, the helical trajectory of the particles may significantly affect the heat load distribution in the edges vicinity. Heat load simulations were performed with ion orbit modeling that consider the Larmor radius, to study its impact on the thermal distribution of the MB. The photonic simulations showed that it was possible to observe a false hot spot at the top LE corner, with both optical approximation (OA) and ion orbit (IO) modeling, due to reflections and different emissivity values. [ABSTRACT FROM AUTHOR]

Measuring the temperature in plasma-facing components (PFCs) provides information both on plasma parameters in the divertor region and on the thermal stress experienced by PFCs. Fiber Bragg gratings (FBGs) are interesting candidates for this application because they are immune to electromagnetic interferences and their ability to be multiplexed allows an extended spatial coverage. Four fibers, each of them including eleven regenerated Bragg gratings, have been embedded in tungsten-coated graphite components and operated up to their signal-collapsing limit at 800 °C. Extending the measurement range towards higher temperatures increases the sensitivity to plasma parameters and allows withstanding higher energy experiments. To overcome thermal limitations, the system is up-graded using femtosecond laser inscribed fibers. In addition to their outstanding thermal stability, femtosecond FBGs benefit from higher signal-to-noise ratios than regenerated FBGs. The paper addresses femtosecond FBGs design and issues relative to their integration inside the actively cooled ITER-like PFCs of the WEST tokamak. The period and length of the gratings are designed to increase the number of measurement spots to fourteen gratings per fiber, regularly distributed over 17 cm, while ensuring robust detection even with strong thermal gradients (no overlapping or deformation of Bragg peaks). The system operates up to 1200 °C with gradients reaching 200 °C/mm perpendicularly and 40 °C/mm in parallel to the fiber. FBGs are inserted in actively cooled ITER-like PFCs through a 2.5 mm deep lateral groove localized at 5 mm beneath the top of bulk tungsten monoblocks. A PFC mock-up machined with a groove has been tested under HHF facility to assess the effect of the groove on monoblocks thermal behavior. The test demonstrates that machined monoblocks behave as expected from simulation and can withstand 20 MW/m2 heat flux (i.e. 1200 °C in the fiber) with 20 % overheating as compared to intact monoblocks. [ABSTRACT FROM AUTHOR]