1,330 results on '"Hakola, A."'
Search Results
2. Intake of B vitamins and the risk of developing islet autoimmunity and type 1 diabetes in the TEDDY study
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Hakola, Leena, Mramba, Lazarus K., Uusitalo, Ulla, Andrén Aronsson, Carin, Hummel, Sandra, Niinistö, Sari, Erlund, Iris, Yang, Jimin, Rewers, Marian J., Akolkar, Beena, McIndoe, Richard A., Rich, Stephen S., Hagopian, William A., Ziegler, Anette, Lernmark, Åke, Toppari, Jorma, Krischer, Jeffrey P., Norris, Jill M., and Virtanen, Suvi M.
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- 2024
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3. Firefront Forecasting in Boreal Forests: Machine Learning Approach to Predict Wildfire Propagation
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A.-M. Raita-Hakola and I. Pölönen
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Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Applied optics. Photonics ,TA1501-1820 - Abstract
Wildfires have become increasingly prevalent worldwide due to climate change, posing significant threats to human lives, property, and natural ecosystems. The rapid progression of wildfires necessitates predictive computational models to assist firefighters in effectively developing strategies to control firefronts. However, existing models often face challenges in computational complexity as the firefront expands. This study aims to develop a faster, more computationally efficient, deep-learning-based model for predicting wildfire spread. We hypothesise that firefront propagation can be modelled using stochastic cellular automata and that a deep-learning model can mimic this approach. With this in mind, we will first introduce our in-house stochastic cellular automata model, which is being validated with data from a known Finnish wildfire. After that, we propose a novel deep-learning model which uses the data generated by our cellular automata. The deep-learning-based model was based on Unet architecture, and it is capable of predicting firefront progression accurately and efficiently one time-step at a time. The model provided realistic simulations of firefronts with high computational efficiency, leaving future development needs to longer time series. One potential application of the developed model is in UAV-based real-time wildfire management systems.
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- 2024
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4. Social-, Health Care and Rehabilitation Educators' Competence: A Cross-Sectional Study
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K. Mikkonen, P. L. Sorvari, H. Kuivila, T. Sjögren, H. Korpi, C. Koskinen, M. Koskinen, M. Koivula, M. Koskimäki, M. L. Lähteenmäki, T. Saaranen, M. Sormunen, L. Salminen, H. Mäki-Hakola, O. Wallin, A. M. Tuomikoski, A. Holopainen, and M. Kääriäinen
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An educator's competence influences the implementation of evidence-based education and the overall quality of social and health care. This study aimed to identify distinct competence profiles from Finnish social, health and rehabilitative care educators, as well as describe which personal and professional characteristics influenced belonging to a certain profile. Data were collected from 28 educational organizations located throughout Finland using the Health and Social Care Educators' Competence instrument. The survey was answered by 422 educators. The performed K-means cluster analysis identified three distinct educator competence profiles, which differed in terms of self-assessed expertise in various competence areas and certain background characteristics. The results highlight that educational institutions should concentrate on refining the digital competence of educators, which requires networking, collaboration, and work-related pedagogical competence. The differences in evaluation identified for the three profiles demonstrates that more experienced educators should mentor their less experienced counterparts to ensure a high quality of education.
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- 2024
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5. Detecting potential outliers in longitudinal data with time-dependent covariates
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Mramba, Lazarus K., Liu, Xiang, Lynch, Kristian F., Yang, Jimin, Aronsson, Carin Andrén, Hummel, Sandra, Norris, Jill M., Virtanen, Suvi M., Hakola, Leena, Uusitalo, Ulla M., and Krischer, Jeffrey P.
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- 2024
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6. Development of a Qualitative Tool for Sustainability Assessment and Application of the Tool to Benchmark Electronic Smart Labels
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Hakola, Liisa, Smolander, Maria, Orko, Inka, Sokka, Laura, and Välimäki, Marja
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- 2024
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7. 5 WAYS: to Improve the Sustainability of Electronics
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Hakola, Liisa and Smolander, Maria
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Finland. VTT Technical Research Centre of Finland ,Business ,Computers and office automation industries ,Electronics and electrical industries - Abstract
New initiatives focused on electronics circularity are putting the pressure on manufacturers to create more sustainable flexible products. This article outlines five plans of attack. BY 2030, GLOBAL electronic waste [...]
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- 2024
8. Maternal gluten, cereal, and dietary fiber intake during pregnancy and lactation and the risk of islet autoimmunity and type 1 diabetes in the child
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Anna, Eurén, Heikki, Hyöty, Kalle, Kurppa, Jutta, Laiho, Olli, Laitinen, Jussi, Lehtonen, Katri, Lindfors, Maria, Lönnrot, Johannes, Malkamäki, Noora, Nurminen, Matti, Nykter, Sami, Oikarinen, Leena, Puustinen, Amirbabak, Sioofy-Khojine, Keijo, Viiri, Daniel, Agardh, Andrén, Aronsson Carin, Markus, Lundgren, Iida, Mäkelä, Martin, Romantschuk, Laura, Soininen, Nicolai A, Lund-Blix, Maria, Magnus, Aino-Kaisa, Rantala, Lars, Stene, Ketil, Størdal, German, Tapia, Laura, Elo, Sini, Junttila, Riitta, Lahesmaa, Johanna, Lempainen, Robert, Moulder, Omid, Rasool, Tomi, Suomi, Jorma, Toppari, Ubaid, Ullah, Riitta, Veijola, Aleksandr, Peet, Kärt, Simre, Vallo, Tillmann, Elena, Bargagli, Francesco, Dotta, Laura, Nigi, Guido, Sebastiani, Leena, Hakola, Hannu, Kiviranta, Panu, Rantakokko, Suvi M, Virtanen, Ondrej, Cinek, Eva, Fronkova, Jaroslav, Havlik, Matthieu, Molinier, Juha, Pajula, Eija, Parmes, Juha, Pärkkä, Petri, Saviranta, Peter, Ylén, Alar, Aints, Anu, Bärenson, Anne, Kirss, Ivo, Laidmäe, Astrid, Oras, Aili, Tagoma, Raivo, Uibo, Tamara, Vorobjova, Loïc, Burr, Stefano, Cattaneo, Hui, Chai-Gao, Peter, Cristofollini, Silvia, Generelli, Samantha, Paoletti, Edith, Ruth, Gabriele, Berg, Wisnu, Wicaksono, Joseph, Petrosino, Rainer, Thiel, Schmidtmann, Daniel, Rosanna, Salo, Lauri, Häme, Alexander, Berler, Korina, Papadopoulou, Hans, Bisgaard, Klaus, Bonnelykke, Sarah, Brandt, Astrid, Sevelsted, Jakob, Stokholm, Jonathan, Thorsen, Mikael, Knip, Aki, Sinkkonen, Marja, Roslund, Hakola, Leena, Lund-Blix, Nicolai A., Takkinen, Hanna-Mari, Tapanainen, Heli, Niinistö, Sari, Korhonen, Tuuli E., Stene, Lars C., Hyöty, Heikki, Toppari, Jorma, Ilonen, Jorma, Knip, Mikael, Veijola, Riitta, and Virtanen, Suvi M.
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- 2024
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9. Shipping and algae emissions have a major impact on ambient air mixing ratios of non-methane hydrocarbons (NMHCs) and methanethiol on Utö Island in the Baltic Sea
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H. Hellén, R. Kouznetsov, K. Kraft, J. Seppälä, M. Vestenius, J.-P. Jalkanen, L. Laakso, and H. Hakola
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Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The mixing ratios of highly volatile organic compounds (VOCs) were studied on Utö Island in the Baltic Sea. Measurements of non-methane hydrocarbons (NMHCs) and methanethiol (unexpectedly found during the experiment) were conducted using an in situ thermal desorption–gas chromatography–flame ionization detector/mass spectrometer (TD-GC-FID/MS) from March 2018 until March 2019. The mean mixing ratios of NMHCs (alkanes, alkenes, alkynes, and aromatic hydrocarbons) were at the typical levels for rural/remote sites in Europe, and, as expected, the highest mixing ratios were measured in winter, while in the summertime, the mixing ratios remained close to or below detection limits for most of the studied compounds. Sources of NMHCs during wintertime were studied using positive matrix factorization (PMF) together with wind direction analyses and source area estimates. Shipping was found to be a major local anthropogenic source of NMHCs with a 21 % contribution. It especially contributed to ethene, propene, and ethyne mixing ratios. Other identified sources were petrol fuel (15 %), traffic exhaust (14 %), local solvents (6 %), and long-range-transported background (42 %). Contrary to NMHCs, high mixing ratios of methanethiol were detected in summertime (July mean of 1000 pptv). The mixing ratios followed the variations in seawater temperatures and sea level height and were highest during the daytime. Biogenic phytoplankton or macroalgae emissions were expected to be the main source of methanethiol.
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- 2024
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10. Divertor erosion at ASDEX Upgrade during helium plasma operations
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Tomi Vuoriheimo, Antti Hakola, Jari Likonen, Karl Krieger, Martin Balden, Iva Bogdanović Radović, Georgios Provatas, Zdravko Siketić, Karla Ivanković Nizić, Marcin Rasinski, and Sebastijan Brezinsek
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Erosion ,Material migration ,ASDEX Upgrade ,Marker samples ,Helium plasma ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
The effect of helium plasma operation on the erosion of plasma-facing components at the low-field side divertor of ASDEX Upgrade was investigated during the 2022 helium experimental campaign. A set of tungsten-covered graphite samples with small platinum marker spots was exposed to both L-mode and H-mode plasma discharges. The highest net erosion of over 1.1 nm/s was observed around the H-mode strike point similar to the case in deuterium plasma. Significant helium inventories of about 6 × 1016 He/cm2 were measured in the scrape-off layer region of the divertor. Impurity deposition including boron and deuterium showed a distinct peak up to 2.4 × 1017 B/cm2 and 1.0 × 1016 D/cm2 between the strike points, and significant boron inventories up to 5.9 × 1016 B/cm2 were also measured on the scrape-off layer side of the H-mode strike point. Platinum re-deposition was not detected between the marker spots, suggesting that it occurs only very locally within the markers. Overall erosion was, as expected, higher than in deuterium discharges, and it also remained comparatively high towards the scrape-off layer, unlike with deuterium.
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- 2024
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11. Laser-induced breakdown spectroscopy for helium detection in beryllium coatings
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Indrek Jõgi, Peeter Paris, Jasper Ristkok, Alicia Marin Roldán, Pavitra Ganapati Bhat, Pavel Veis, Juuso Karhunen, Salvatore Almaviva, Wojciech Gromelski, Paul Dinca, Corneliu Porosnicu, Iva Bogdanović Radović, Zdravko Siketić, Paweł Gąsior, Jari Likonen, and Antti Hakola
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LIBS ,He retention ,Be coatings ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Laser Induced Breakdown Spectroscopy (LIBS) method is considered to be a promising tool for analyzing the retention of hydrogen isotopes (D and T) and helium (He) on the first walls and divertor regions of future fusion reactors. Helium will be produced in DT reactions but could also be used in the initial non-nuclear phases of DEMO concepts. The present study investigates the He detection by LIBS method in the Be coatings simulating the deposits on the divertor plasma-facing components of JET while the results are also relevant for He detection in the deposits of other wall materials. The study was carried out in a vacuum vessel filled with 2–40 mbar argon background gas. It was shown that 2.8 at. % of He was confidently detectable by LIBS at optimized measurement conditions and the estimated limit of detection at used experimental conditions is approximately 0.7 at. %. The intensity of the He emission line at 587.56 nm was the strongest at the center of the laser-induced plasma plume. The He line intensity increased with the pressure of Ar gas but the broadening of the He line and the increase of the background emission and noise set an upper limit to the Ar background pressure usable for He detection. The application of the calibration-free LIBS procedure resulted in the overestimation of the He/Be ratio by several orders of magnitude. The overestimation can be explained by the deviation of LIBS plasma from the local thermodynamic equilibrium, which is caused by the very high excitation energy of He atoms.
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- 2024
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12. Food Consumption and Risk of Islet Autoimmunity and Type 1 Diabetes in Children at Increased Genetic Susceptibility for Type 1 Diabetes
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Virtanen, Suvi M, Peltonen, Essi J, Hakola, Leena, Niinistö, Sari, Takkinen, Hanna-Mari, Ahonen, Suvi, Åkerlund, Mari, Uusitalo, Ulla, Mattila, Markus, Salo, Tuuli EI, Ilonen, Jorma, Toppari, Jorma, Veijola, Riitta, Knip, Mikael, and Nevalainen, Jaakko
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- 2024
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13. Deuterium loading of redeposited-like W coatings present in tokamaks by ion implantation
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Mateus, R., Dellasega, D., Passoni, M., Siketić, Z., Bogdanović Radović, I., Likonen, J., Hakola, A., and Alves, E.
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- 2024
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14. Prenatal and Postnatal Exposure to Antibiotics and the Risk of Type 1 Diabetes in Finnish Children: A Registry-based Study
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Hakola, Leena, Lundqvist, Annamari, Gissler, Mika, Virta, Lauri J., Virtanen, Suvi M., and Metsälä, Johanna
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- 2025
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15. COMBINING YOLO V5 AND TRANSFER LEARNING FOR SMOKE-BASED WILDFIRE DETECTION IN BOREAL FORESTS
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A.-M. Raita-Hakola, S. Rahkonen, J. Suomalainen, L. Markelin, R. Oliveira, T. Hakala, N. Koivumäki, E. Honkavaara, and I. Pölönen
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Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Applied optics. Photonics ,TA1501-1820 - Abstract
Wildfires present severe threats to various aspects of ecosystems, human settlements, and the environment. Early detection plays a critical role in minimizing the destructive consequences of wildfires. This study introduces an innovative approach for smoke-based wildfire detection in Boreal forests by combining the YOLO V5 algorithm and transfer learning. YOLO V5 is renowned for its real-time performance and accuracy in object detection. Given the scarcity of labelled smoke images specific to wildfire scenes, transfer learning techniques are employed to address this limitation. Initially, the generalisability of smoke as an object is examined by utilising wildfire data collected from diverse environments for fine-tuning and testing purposes in Boreal forest scenarios. Subsequently, Boreal forest fire data is employed for training and fine-tuning to achieve high detection accuracy and explore benchmarks for effective local training data. This approach minimises extensive manual labelling efforts while enhancing the accuracy of smoke-based wildfire detection in Boreal forest environments. Experimental results validate the efficacy of the proposed approach. The combined YOLO V5 and transfer learning framework demonstrates a high detection accuracy, making it a promising solution for automated wildfire detection systems. Implementing this methodology can potentially enhance early detection and response to wildfires in Boreal forest regions, thereby contributing to improved disaster management and mitigation strategies.
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- 2023
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16. Divertor erosion at ASDEX Upgrade during helium plasma operations
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Vuoriheimo, Tomi, Hakola, Antti, Likonen, Jari, Krieger, Karl, Balden, Martin, Bogdanović Radović, Iva, Provatas, Georgios, Siketić, Zdravko, Ivanković Nizić, Karla, Rasinski, Marcin, and Brezinsek, Sebastijan
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- 2024
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17. Wall conditions in WEST during operations with a new ITER grade, actively cooled divertor
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Gallo, A., Moreau, Ph., Douai, D., Alarcon, T., Afonin, K., Anzallo, V., Bisson, R., Bucalossi, J., Caprin, E., Corre, Y., De Combarieu, M., Desgranges, C., Devynck, P., Ekedahl, A., Fedorczak, N., Gaspar, J., Grosjean, A., Guillemaut, C., Guirlet, R., Gunn, J.P., Hillairet, J., Loarer, T., Maget, P., Manas, P., Morales, J., Pellissier, F.P., Tsitrone, E., Krieger, K., Hakola, A., and Widdowson, A.
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- 2024
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18. High Concentrations of Immunoglobulin G Against Cow Milk Proteins and Frequency of Cow Milk Consumption Are Associated With the Development of Islet Autoimmunity and Type 1 Diabetes—The Trial to Reduce Insulin-dependent Diabetes Mellitus (IDDM) in the Genetically at Risk (TRIGR) Study
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Niinistö, Sari, Cuthbertson, David, Miettinen, Maija E, Hakola, Leena, Nucci, Anita, Korhonen, Tuuli E, Hyöty, Heikki, Krischer, Jeffrey P, Vaarala, Outi, Knip, Mikael, Savilahti, Erkki, and Virtanen, Suvi M
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- 2024
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19. Gut Inflammation Markers, Diet, and Risk of Islet Autoimmunity in Finnish Children – A Nested Case-Control Study
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Salo, Tuuli EI, Hakola, Leena, Niinistö, Sari, Takkinen, Hanna-Mari, Ahonen, Suvi, Puustinen, Leena, Ilonen, Jorma, Toppari, Jorma, Veijola, Riitta, Hyöty, Heikki, Knip, Mikael, and Virtanen, Suvi M
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- 2024
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20. Laser-induced breakdown spectroscopy for helium detection in beryllium coatings
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Jõgi, Indrek, Paris, Peeter, Ristkok, Jasper, Roldán, Alicia Marin, Bhat, Pavitra Ganapati, Veis, Pavel, Karhunen, Juuso, Almaviva, Salvatore, Gromelski, Wojciech, Dinca, Paul, Porosnicu, Corneliu, Radović, Iva Bogdanović, Siketić, Zdravko, Gąsior, Paweł, Likonen, Jari, and Hakola, Antti
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- 2024
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21. Changeover between helium and hydrogen fueled plasmas in JET and WEST
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T. Wauters, R. Bisson, E. Delabie, D. Douai, A. Gallo, J. Gaspar, I. Jepu, Y. Kovtun, E. Pawelec, D. Matveev, A. Meigs, S. Brezinsek, I. Coffey, T. Dittmar, N. Fedorczak, J. Gunn, A. Hakola, P. Jacquet, K. Kirov, E. Lerche, J. Likonen, E. Litherland-Smith, T. Loarer, P. Lomas, C. Lowry, M. Maslov, I. Monakhov, J. Morales, C. Noble, R. Nouailletas, B. Pégourié, C. Perez von Thun, R.A. Pitts, C. Reux, F. Rimini, H. Sheikh, S. Silburn, H. Sun, D. Taylor, E. Tsitrone, S. Vartanian, E. Wang, and A. Widdowson
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JET ,WEST ,Changeover ,Helium ,Hydrogen ,ICWC ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
The pre-fusion power operation (PFPO) phase of ITER, as described in the ITER research plan with Staged Approach,22 ITER Organization, “ITER Research Plan within the Staged Approach,” ITR-18–003, Aug. 2018. includes both hydrogen (H) and helium (He) plasma operations. In preparation for PFPO, both WEST and JET ran He plasma campaigns to study plasma-wall interactions in a tungsten environment. The campaigns included a back-and-forth transition between H or deuterium (D) and He plasma operation allowing the assessment of the achievable plasma content as well as the accessible wall reservoirs for respective species. The WEST changeovers included tokamak pulses with a fixed divertor configuration. The JET changeovers applied ion cyclotron wall conditioning (ICWC) and tokamak pulses including limiter phases and four different divertor configurations. Glow discharge conditioning (GDC) was applied to complete the changeovers. The results are characterized by subdivertor optical and mass spectrometric gas analyzers and spatially resolved optical emission spectroscopy. A He content of 96–97 % after H operations is achieved by tens of ICWC pulses (JET) and several dedicated diverted plasmas (WEST and JET), while a fivefold is estimated to be required for the back transition. Effective pumping of the wall released species is a key parameter for a fast changeover. Upon applying higher heating power, the relative content of the fueled plasma species decreases. The JET gas balance analysis indicates that He operation may increase H retention. WEST divertor spectroscopy indicates a larger He inventory near the inner divertor strike line. He GDC has a clear effect on the He recycling light at the WEST divertor while D GDC did not reduce the long lasting He content observed in D pulses after the JET He campaign.
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- 2024
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22. Changeover between helium and hydrogen fueled plasmas in JET and WEST
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Wauters, T., Bisson, R., Delabie, E., Douai, D., Gallo, A., Gaspar, J., Jepu, I., Kovtun, Y., Pawelec, E., Matveev, D., Meigs, A., Brezinsek, S., Coffey, I., Dittmar, T., Fedorczak, N., Gunn, J., Hakola, A., Jacquet, P., Kirov, K., Lerche, E., Likonen, J., Litherland-Smith, E., Loarer, T., Lomas, P., Lowry, C., Maslov, M., Monakhov, I., Morales, J., Noble, C., Nouailletas, R., Pégourié, B., Perez von Thun, C., Pitts, R.A., Reux, C., Rimini, F., Sheikh, H., Silburn, S., Sun, H., Taylor, D., Tsitrone, E., Vartanian, S., Wang, E., and Widdowson, A.
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- 2024
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23. Fruit, berry, and vegetable consumption and the risk of islet autoimmunity and type 1 diabetes in children—the Type 1 Diabetes Prediction and Prevention birth cohort study
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Mattila, Markus, Takkinen, Hanna-Mari, Peltonen, Essi J, Vuorinen, Anna-Leena, Niinistö, Sari, Metsälä, Johanna, Ahonen, Suvi, Åkerlund, Mari, Hakola, Leena, Toppari, Jorma, Ilonen, Jorma, Veijola, Riitta, Haahtela, Tari, Knip, Mikael, and Virtanen, Suvi M
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- 2024
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24. Patterns and Determinants of Micronutrient Dietary Biomarkers and Their Associations with Dietary Intakes in Young Children
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Clasen, Joanna L, Yang, Jimin, Hakola, Leena, Arohonka, Petra, Lynch, Kristian, Parikh, Hemang M, Andrén Aronsson, Carin, Uusitalo, Ulla, Norris, Jill M, Virtanen, Suvi M, and Erlund, Iris
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- 2024
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25. Dietary fatty acid intake in childhood and the risk of islet autoimmunity and type 1 diabetes: the DIPP birth cohort study
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Hakola, Leena, Vuorinen, Anna-Leena, Takkinen, Hanna-Mari, Niinistö, Sari, Ahonen, Suvi, Rautanen, Jenna, Peltonen, Essi J., Nevalainen, Jaakko, Ilonen, Jorma, Toppari, Jorma, Veijola, Riitta, Knip, Mikael, and Virtanen, Suvi M.
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- 2023
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26. LIBS depth profiling of Be-containing samples with different gaseous impurity concentrations
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P.G. Bhat, P. Veis, A. Marín Roldán, J. Karhunen, P. Paris, I. Jõgi, A. Hakola, J. Likonen, S. Almaviva, W. Gromelski, M. Ladygina, P. Gasior, J. Ristkok, I. Bogdanović Radović, Z. Siketić, O. Romanenko, C. Porosnicu, and C. Lungu
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LIBS depth profiles ,Be-containing samples ,Deuterium ,Seeding gases ,Neon detectability ,Ablation rates ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Understanding the interaction between the fusion plasma and the plasma-facing materials (PFMs) is crucial for achieving the optimal performance, safety, and lifetime of the fusion devices. Relevant materials have been intensely studied to determine fuel retention and the composition of the co-deposited layers on the PFMs by depth profile analysis using Laser-Induced Breakdown Spectroscopy (LIBS) and Calibration-Free (CF)-LIBS. However, the comparison between the layers containing a mixture of different (seeding) gases using LIBS, has not been studied systematically. Consequently, the aim of this work is the LIBS depth profile analysis of Be-based samples containing the fuel (D) and one of the seeding gases (N, Ne, He) with variable concentrations to study the potential impact on fuel retention in the PFMs. The LIBS measurements were performed using Nd:YAG laser (1064 nm) under Ar atmosphere (at 2 and 100 mbar). In LIBS the ablation rate was evaluated, spectral lines of all relevant elements except N and Ne were detected and compared with the SIMS depth profiles. The reasons for the non-detectability of Ne are discussed in detail.
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- 2023
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27. FIB line marking as a tool for local erosion/deposition/fuzz formation measurements in ASDEX Upgrade during the He campaign
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M. Rasiński, S. Brezinsek, A. Kreter, T. Dittmar, K. Krieger, M. Balden, P. de Marne, R. Dux, M. Faitsch, A. Hakola, J. Likonen, E. Tsitrone, and V. Rohde
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FIB line marking ,W fuzz He plasma ,ASDEX Upgrade ,Microstructure ,Erosion and re-deposition ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Tungsten (W) is the prime candidate for the plasma facing material in present and future fusion devices. When exposed to a plasma containing He ions, W can exhibit creation of sub-surface nano-bubbles leading to formation of nano-tendrils called fuzz. Formation of W fuzz was confirmed by many laboratory experiments including He loading in linear plasma devices. There is, however, limited experience related to the parameter space for fuzz formation and re-erosion in a tokamak environment. For this reason, a dedicated experiment was carried out in ASDEX Upgrade (AUG) during its 2022 He campaign to study the evolution of fuzz-like W structures.Twelve tungsten samples were mechanically polished to a mirror-like surface finish. Six of them were subsequently exposed to a He plasma in the PSI-2 linear device in order to establish a fuzz layer with a thickness of 600 – 800 nm. Before exposure in AUG, all samples were pre-characterized by Focused Ion Beam (FIB) cross-sectioning. In total 48 FIB cross-sections with line markings for quantification of local erosion, deposition and fuzz formation were prepared – 4 on each sample. The samples were placed in two parallel poloidal rows spanning a range of 20 cm around the outer strike line position (OSP). They were subsequently exposed in AUG to a series of 14 consecutive discharges, 8 in H-mode and 6 in L-mode.Detailed analysis by means of electron microscopy revealed on the samples regions of erosion, deposition and fuzz formation. Below the H-mode OSP, homogeneous co-deposits containing W and O, with a thickness up to 400 nm, were found. In the close vicinity of the H-mode OSP, significant erosion of pre-exposure PSI-2 fuzz was observed. The erosion reached up to 100 – 250 nm, depending on the location. In addition, the initially polished samples did not show any newly formed fuzz in that zone. Above the H-mode OSP, new fuzz was formed with a thickness of up to 1 μm. There was no Mo found in the newly formed fuzz. Pre-exposure PSI-2 fuzz was either removed or modified.
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- 2023
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28. Comparison of ion cyclotron wall conditioning discharges in hydrogen and helium in JET
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Y. Kovtun, T. Wauters, D. Matveev, R. Bisson, I. Jepu, S. Brezinsek, I. Coffey, E. Delabie, A. Boboc, T. Dittmar, A. Hakola, P. Jacquet, K. Kirov, E. Lerche, J. Likonen, E. Litherland-Smith, T. Loarer, P. Lomas, C. Lowry, E. Pawelec, C. Perez von Thun, A. Meigs, M. Maslov, I. Monakhov, C. Noble, S. Silburn, H. Sun, D. Taylor, E. Tsitrone, A. Widdowson, H. Sheikh, and D. Douai
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Wall conditioning ,Radio-frequency discharge ,Tokamak ,Plasma production ,Ion cyclotron ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
This paper explores the plasma parameters of helium and hydrogen Ion Cyclotron Wall Conditioning (ICWC) discharges performed in JET as part of a He/H fuelling changeover experiment. The conducted study shows that plasma with a higher density is formed in helium than in hydrogen. A distinct glow in the ion cyclotron resonance zone is observed throughout the discharge in He. In H-ICWC discharges, a lower radio-frequency coupling efficiency and coupled power was observed than in He-ICWC discharges. While the helium concentration decreased with the number of H-ICWC pulses and the same for hydrogen in He-ICWC, which is the intended result of the plasma wall interaction in the ICWC changeover procedure, the main features of hydrogen as well as the helium IC discharge do not change dramatically.
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- 2023
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29. Comparison of ion cyclotron wall conditioning discharges in hydrogen and helium in JET
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Kovtun, Y., Wauters, T., Matveev, D., Bisson, R., Jepu, I., Brezinsek, S., Coffey, I., Delabie, E., Boboc, A., Dittmar, T., Hakola, A., Jacquet, P., Kirov, K., Lerche, E., Likonen, J., Litherland-Smith, E., Loarer, T., Lomas, P., Lowry, C., Pawelec, E., Perez von Thun, C., Meigs, A., Maslov, M., Monakhov, I., Noble, C., Silburn, S., Sun, H., Taylor, D., Tsitrone, E., Widdowson, A., Sheikh, H., and Douai, D.
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- 2023
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30. LIBS depth profiling of Be-containing samples with different gaseous impurity concentrations
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Bhat, P.G., Veis, P., Marín Roldán, A., Karhunen, J., Paris, P., Jõgi, I., Hakola, A., Likonen, J., Almaviva, S., Gromelski, W., Ladygina, M., Gasior, P., Ristkok, J., Bogdanović Radović, I., Siketić, Z., Romanenko, O., Porosnicu, C., and Lungu, C.
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- 2023
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31. FIB line marking as a tool for local erosion/deposition/fuzz formation measurements in ASDEX Upgrade during the He campaign
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Rasiński, M., Brezinsek, S., Kreter, A., Dittmar, T., Krieger, K., Balden, M., de Marne, P., Dux, R., Faitsch, M., Hakola, A., Likonen, J., Tsitrone, E., and Rohde, V.
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- 2023
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32. Nanostructure formation and D retention in redeposited-like W exposed to linear plasmas
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Dellasega, D., Alberti, G., Fortuna-Zalesna, E., Zielinski, W., Pezzoli, A., Möller, S., Unterberg, B., Passoni, M., and Hakola, A.
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- 2023
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33. The Use of Patient-Oriented Mobile Phone Apps in Oral Health: Scoping Review
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Elina Väyrynen, Sanna Hakola, Anniina Keski-Salmi, Hannaleena Jämsä, Raija Vainionpää, and Saujanya Karki
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Information technology ,T58.5-58.64 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundOral health is a significant part of general health. Poor oral health can influence an individual’s appearance, self-esteem, eating, and speaking. The use of mobile phone apps has been growing in the field of medicine, including dentistry. However, to date, there is no evidence related to the availability of mobile apps focusing on various branches of dentistry. ObjectiveThe aim of this study was to review the scientific literature on the use of patient-oriented mobile phone apps in oral health and summarize the key findings. MethodsA scoping review of published scientific literature on the use of patient-oriented mobile phone apps in oral health was conducted in accordance with the Joanna Briggs Institute. A search was performed in PubMed and Scopus for studies published between January 2000 and June 2021 that were written in English. All study types except for those reporting developmental protocols were included in this review. In total, 2 reviewers independently screened the studies using the eligibility criteria. The study protocol was registered in the Open Science Framework registries in June 2021. ResultsThe initial search yielded a total of 977 studies, 45 (4.6%) of which met the inclusion criteria. All the studies (45/45, 100%) were published after 2009. Most studies (31/45, 69%) concerned oral health promotion using mobile phone apps, followed by behavior management (5/45, 11%). More than half (23/45, 51%) of the included studies were conducted in Asian countries. Overall, 31% (14/45) of the studies focused on adolescents. A total of 51% (23/45) of the studies were randomized controlled trials (RCTs). Approximately 39% (9/23) of the included RCT studies reported a substantial reduction in dental plaque, and 26% (6/23) of the studies reported significant improvement in gingival health. Regarding dental anxiety management, 13% (3/23) of the RCT studies reported a significant decrease in mean heart rate and lower Facial Image Scale scores. ConclusionsAccording to the literature, the use of mobile apps in oral health is increasing among patients, mainly children and adolescents. Many studies that have used mobile apps have focused on promoting oral health. However, other areas such as diagnostic and remote consultations (teledentistry) have until recently been neglected despite their great potential.
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- 2023
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34. Nanostructure formation and D retention in redeposited-like W exposed to linear plasmas
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D. Dellasega, G. Alberti, E. Fortuna-Zalesna, W. Zielinski, A. Pezzoli, S. Möller, B. Unterberg, M. Passoni, and A. Hakola
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Redeposited W ,Nanostructure formation ,Linear machine ,D retention ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Different kinds of W layers resembling the ones found after campaigns in tokamak were produced by Pulsed Laser Deposition: namely nanocrystalline, amorphous and porous W layers. Films were exposed to divertor relevant D plasma, in PSI-2; D retention as well as nanostructure formation were investigated. For nanocrystalline W films we found lamellar structures that coalesce with increasing D fluence. Instead, on amorphous W no lamellas were formed but a new random string-like shape. A higher oxygen content in the W layer results in an evolution of the shape of the nanostructures in straight parallel lines with acute angles. The presence of a porous structure morphology hinders the formation of surface nanostructures. Reviewing results from different linear devices including also bulk W, we observe that, when formed, nanostructures appear in general with a fluence threshold of 3–5 × 1025 D/m2 regardless the impinging D flux. D retention shows an unusual trend increasing fluence and is enhanced by the presence of amorphous structure and open morphology. Amorphous W films exhibit higher D retention (3 orders of magnitude) compared to crystalline W. When the amorphous W is annealed, retention returns to the standard values of bulk W regardless the presence of a layered structure parallel to the substrate. Porous W, thanks to the high surface to volume ratio and the presence of void distribution along the growth direction, favors higher recycling and thus limits the D uptake during exposure. The presence of O, in the investigated coatings, seems to have little effect on D retention.
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- 2023
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35. Ex Situ LIBS Analysis of WEST Divertor Wall Tiles after C3 Campaign
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Indrek Jõgi, Peeter Paris, Elodie Bernard, Mathilde Diez, Emmanuelle Tsitrone, Antti Hakola, Jari Likonen, Tomi Vuoriheimo, Eduard Grigore, the WEST Team, and EUROfusion WP PFC/PWIE Contributors
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WEST tokamak ,LIBS ,composition analysis ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Fuel retention monitoring in tokamak walls requires the development of remote composition analysis methods such as laser-induced breakdown spectroscopy (LIBS). The present study investigates the feasibility of the LIBS method to analyse the composition and fuel retention in three samples from WEST divertor erosion marker tiles after the experimental campaign C3. The investigated samples originated from tile regions outside of strong erosion and deposition regions, where the variation of thin deposit layers is relatively small and facilitates cross-comparison between different analysis methods. The depth profiles of main constituents W, Mo and C were consistent with depth profiles determined by other composition analysis methods, such as glow-discharge optical emission spectroscopy (GDOES) and secondary ion mass spectrometry (SIMS). The average LIBS depth resolution determined from depth profiles was 100 nm/shot. The averaging of the spectra collected from multiple spots of a same sample allowed us to improve the signal-to-noise ratio, investigate the presence of fuel D and trace impurities such as O and B. In the investigated tile regions with negligible erosion and deposition, these impurities were clearly detectable during the first laser shot, while the signal decreased to noise level after a few subsequent laser shots at the same spot. LIBS investigation of samples originating from the deposition regions of tiles may further clarify LIBS’ ability to investigate trace impurities.
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- 2023
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36. Filming Death : End-of-Life Documentary Cinema
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Hakola, Outi and Hakola, Outi
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- 2024
37. Deuterium and helium retention in W and W-Ta coatings irradiated with energetic ion beams
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Mateus, R., Catarino, N., Dias, M., Alves, L.C., Romanenko, O., Siketić, Z., Radović, I. Bogdanović, Hakola, A., Grigore, E., and Alves, E.
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- 2023
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38. WEST full tungsten operation with an ITER grade divertor
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J. Bucalossi, A. Ekedahl, and the WEST Team, J. Achard, K. Afonin, O. Agullo, T. Alarcon, L. Allegretti, F. Almuhisen, H. Ancher, G. Antar, Y. Anquetin, S. Antusch, V. Anzallo, C. Arnas, J.F. Artaud, M.H. Aumeunier, S.G. Baek, X.Y. Bai, M. Balden, C. Balorin, T. Barbui, A. Barbuti, J. Barlerin, J. Barra, V. Basiuk, T. Batal, O. Baulaigue, A. Bec, M. Becoulet, E. Benoit, E. Bernard, J.M. Bernard, M. Bernert, N. Bertelli, E. Bertrand, P. Beyer, J. Bielecki, P. Bienvenu, R. Bisson, B. Bliewert, G. Bodner, S. Bose, C. Bottereau, C. Bouchand, Y. Boumendjel, F. Bouquey, C. Bourdelle, J. Bourg, S. Brezinsek, F. Brochard, C. Brun, V. Bruno, H. Bufferand, A. Bureau, S. Burles, Y. Camenen, B. Cantone, E. Caprin, M. Carole, S. Carpentier-Chouchana, G. Caulier, F. Causa, N. Cazanave, N. Chanet, O. Chellai, Y. Chen, M. Chernyshova, P. Chmielewski, W. Choe, A. Chomiczewska, G. Ciraolo, F. Clairet, J. Coenen, L. Colas, G. Colledani, J. Colnel, P. Coquillat, E. Corbel, Y. Corre, X. Courtois, T. Czarski, A. Da Ros, R. Daniel, J. Daumas, M. De Combarieu, P. De Vries, C. Dechelle, F. Deguara, R. Dejarnac, J.M. Delaplanche, L.F. Delgado-Aparicio, E. Delmas, L. Delpech, C. Desgranges, P. Devynck, J. Denis, S. Di Genova, R. Diab, A. Diallo, M. Diez, G. Dif-Pradalier, M. Dimitrova, R. Ding, T. Dittmar, L. Doceul, M. Domenes, D. Donovan, D. Douai, L. Dubus, N. Dumas, R. Dumont, F. Durand, A. Durif, F. Durodié, D. Elbeze, S. Ertmer, A. Escarguel, F. Escourbiac, B. Esposito, K. Ezato, F. Faisse, J.L. Farjon, N. Faure, N. Fedorczak, P. Fejoz, F. Felici, C. Fenzi-Bonizec, F. Ferlay, L. Ferrand, L. Fevre, M. Firdaouss, L. Fleury, D. Flouquet, T. Fonghetti, A. Gallo, X. Garbet, J. Garcia, J.L. Gardarein, L. Gargiulo, P. Garibaldi, S. Garitta, J. Gaspar, E. Gauthier, S. Gazzotti, F. Gely, J. Gerardin, G. Gervasini, E. Geulin, M. Geynet, P. Ghendrih, I. Giacalone, C. Gil, S. Ginoux, S. Girard, E. Giroux, G. Giruzzi, M. Goniche, V. Gorse, T. Gray, E. Grelier, C. Grisolia, A. Grosjean, A. Grosman, O. Grover, D. Guibert, D. Guilhem, C. Guillemaut, B. Guillermin, R. Guirlet, J.P. Gunn, Y. Gunsu, T. Gyergyek, S. Hacquin, A. Hakola, J. Harris, J.C. Hatchressian, W. Helou, P. Hennequin, C. Hernandez, L. Hijazi, J. Hillairet, T. Hirai, G.T. Hoang, C. Honoré, M. Houry, A. Huart, G. Huijsmans, P. Huynh, M. Iafrati, F. Imbeaux, N. Imbert, I. Ivanova-Stanik, P. Ivanova, R. Jalageas, A. Jamann, C. Jammes, A. Jardin, L. Jaubert, G. Jiolat, E. Joffrin, C. Johnson, A. Jonas, A. Kirschner, C.C. Klepper, M. Komm, M. Koubiti, S. Kosslow, J. Kovacic, M. Kozeiha, K. Krieger, K. Krol, I. Kudashev, B. Lacroix, L. Laguardia, V. Lamaison, V. Lapleigne, H. Laqua, C. Lau, Y. Lausenaz, R. Lé, M. Le Bohec, N. Lefevre, N. Lemoine, E. Lerche, Y. Lesourd, L. Letellier, M. Lewerentz, Y. Li, A. Liang, P. Linczuk, C. Linsmeier, M. Lipa, X. Litaudon, X. Liu, J. Llorens, T. Loarer, A. Loarte, T. Loewenhoff, G. Lombard, J. Lore, P. Lorenzetto, B. Lu, A. Lumsdaine, R. Lunsford, T. Lunt, G. Luo, P. Magaud, P. Maget, J.F. Mahieu, P. Maini, P. Malard, K. Malinowski, P. Manas, L. Manenc, V. Maquet, Y. Marandet, C. Martin, E.J. Martin, P. Martino, M. Mayer, D. Mazon, S. Mazzi, P. Messina, L. Meunier, D. Midou, G. Miglionico, Y. Mineo, M. Missirlian, R. Mitteau, B. Mitu, D. Moiraf, P. Mollard, G. Momparler, V. Moncada, T. Mondiere, C. Monti, J. Morales, M. Moreau, Ph. Moreau, Y. Moudden, G. Moureau, D. Mouyon, M. Muraglia, T. Nakano, E. Nardon, A. Neff, F. Nespoli, J. Nichols, L. Nicolas, S. Nicollet, R. Nouailletas, M. Ono, V. Ostuni, O. Paillat, C. Parish, H. Park, H. Parrat, J.Y. Pascal, B. Pegourie, F.P. Pellissier, Y. Peneliau, M. Peret, E. Pignoly, G. Pintsuk, R. Pitts, C. Pocheau, A. Podolnik, C. Portafaix, M. Poulos, P. Prochet, A. Puig Sitjes, R. Ragona, M. Rasinski, S. Ratynskaia, G. Raup, X. Regal-Mezin, C. Reux, J. Rice, M. Richou, F. Rigollet, N. Rivals, H. Roche, S. Rodrigues, J. Romazanov, G. Ronchi, C. Ruset, R. Sabot, A. Saille, R. Sakamoto, B. Salamon, F. Samaille, A. Santagiustina, B. Santraine, Y. Sarazin, O. Sauter, Y. Savoie-Peysson, L. Schiesko, M. Scholz, J.L. Schwob, E. Serre, H. Shin, S. Shiraiwa, Ja. Signoret, O. Skalli-Fettachi, P. Sogorb, Y. Song, A. Spring, P. Spuig, S. Sridhar, B. Stratton, C. Talatizi, P. Tamain, R. Tatali, Q. Tichit, A. Torre, L. Toulouse, W. Treutterer, E. Tsitrone, E.A. Unterberg, G. Urbanczyk, G. Van Rooij, N. Varadarajan, S. Vartanian, E. Velly, J.M. Verger, L. Vermare, D. Vezinet, N. Vignal, B. Vincent, S. Vives, D. Volpe, G. Wallace, E. Wang, L. Wang, Y. Wang, Y.S. Wang, T. Wauters, D. Weldon, B. Wirth, M. Wirtz, A. Wojenski, M. Xu, Q.X. Yang, H. Yang, B. Zago, R. Zagorski, B. Zhang, X.J. Zhang, X.L. Zou, and the EUROfusion Tokamak Exploitation Team
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nuclear fusion ,magnetic confinement ,tokamak ,divertor ,WEST ,ITER ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
The mission of WEST (tungsten-W Environment in Steady-state Tokamak) is to explore long pulse operation in a full tungsten (W) environment for preparing next-step fusion devices (ITER and DEMO) with a focus on testing the ITER actively cooled W divertor in tokamak conditions. Following the successful completion of phase 1 (2016-2021), phase 2 started in December 2022 with the lower divertor made entirely of actively cooled ITER-grade tungsten mono-blocks. A boronization prior the first plasma attempt allowed for a smooth startup with the new divertor. Despite the reduced operating window due to tungsten, rapid progress has been made in long pulse operation, resulting in discharges with a pulse length of 100 s and an injected energy of around 300 MJ per discharge. Plasma startup studies were carried out with equatorial boron nitride limiters to compare them with tungsten limiters, while Ion Cyclotron Resonance Heating assisted startup was attempted. High fluence operation in attached regime, which was the main thrust of the first campaigns, already showed the progressive build up of deposits and appearance of dust, impacting the plasma operation as the plasma fluence increased. In total, the cumulated injected energy during the first campaigns reached 43 GJ and the cumulated plasma time exceeded 5 h. Demonstration of controlled X-Point Radiator regime is also reported, opening a promising route for investigating plasma exhaust and plasma-wall interaction issues in more detached regime. This paper summarises the lessons learned from the manufacturing and the first operation of the ITER-grade divertor, describing the progress achieved in optimising operation in a full W environment with a focus on long pulse operation and plasma wall interaction.
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- 2024
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39. Overview of ASDEX upgrade results in view of ITER and DEMO
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H. Zohm, E. Alessi, C. Angioni, N. Arden, V. Artigues, M. Astrain, O. Asunta, M. Balden, V. Bandaru, A. Banon Navarro, M. Bauer, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, L. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megías, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, A. Castillo Castillo, A. Cathey, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, A. Chomiczewska, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, I. Cziegler, O. D’Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, P. Denner, A. Di Siena, M. Dibon, J.J. Dominguez-Palacios Durán, D. Dunai, M. Dreval, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, B. Esposito, E. Fable, M. Faitsch, D. Fajardo Jimenez, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo, Y. Gao, S. Garavaglia, M. Garcia Muñoz, B. Geiger, L. Giannone, S. Gibson, L. Gil, E. Giovannozzi, I. Girka, O. Girka, T. Gleiter, S. Glöggler, M. Gobbin, J.C. Gonzalez, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, G. Grenfell, H. Greuner, M. Griener, M. Groth, O. Grover, A. Gude, L. Guimarais, S. Günter, D. Hachmeister, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, P. Heinrich, T. Hellsten, S. Henderson, P. Hennequin, M. Herschel, S. Heuraux, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, S. Hörmann, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, J. Illerhaus, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, S. Jachmich, W. Jacob, N. Jaksic, A. Jansen van Vuuren, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, J. Kalis, A. Kappatou, J. Karhunen, C.-P. Käsemann, S. Kasilov, Y. Kazakov, A. Kendl, W. Kernbichler, E. Khilkevitch, M. Kircher, A. Kirk, S. Kjer Hansen, V. Klevarova, F. Klossek, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, M. Krause, I. Krebs, A. Kreuzeder, K. Krieger, O. Kudlacek, D. Kulla, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P. Lainer, P.T. Lang, P. Lauber, M. Lehnen, L. Leppin, E. Lerche, N. Leuthold, L. Li, J. Likonen, O. Linder, H. Lindl, B. Lipschultz, Y. Liu, Z. Lu, T. Luda Di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, V. Maquet, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, M. Markl, L. Marrelli, P. Martin, F. Matos, M. Mayer, P.J. McCarthy, R. McDermott, G. Meng, R. Merkel, A. Merle, H. Meyer, M. Michelini, D. Milanesio, V. Mitterauer, P. Molina Cabrera, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, I. Novikau, S. Nowak, R. Ochoukov, J. Olsen, P. Oyola, O. Pan, G. Papp, A. Pau, G. Pautasso, C. Paz-Soldan, M. Peglau, E. Peluso, P. Petersson, C. Piron, U. Plank, B. Plaum, B. Plöckl, V. Plyusnin, G. Pokol, E. Poli, A. Popa, L. Porte, J. Puchmayr, T. Pütterich, L. Radovanovic, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, A. Redl, D. Réfy, M. Reich, F. Reimold, D. Reiser, M. Reisner, D. Reiter, B. Rettino, T. Ribeiro, D. Ricci, R. Riedl, J. Riesch, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, V. Rohde, G. Ronchi, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, A. Schlüter, J. Scholte, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, N. Schwarz, T. Schwarz-Selinger, J. Schweinzer, F. Sciortino, O. Seibold-Benjak, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, M. Spacek, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, D. Stieglitz, J. Stober, U. Stroth, E. Strumberger, G. Suarez Lopez, W. Suttrop, T. Szepesi, B. Tál, T. Tala, W. Tang, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, M. Tripský, P. Ulbl, G. Urbanczyk, M. Usoltseva, M. Valisa, M. Valovic, S. van Mulders, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, T. Verdier, G. Verdoolaege, N. Vianello, J. Vicente, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, D. Wendler, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, C. Yoo, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, A. Zibrov, M. Zilker, C.F.B. Zimmermann, A. Zito, S. Zoletnik, the EUROfusion Tokamak Exploitation Team, and the ASDEX Upgrade Team
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tokamak ,MHD stability ,transport modelling ,radiative exhaust ,disruption physics ,ELM free scenarios ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Experiments on ASDEX Upgrade (AUG) in 2021 and 2022 have addressed a number of critical issues for ITER and EU DEMO. A major objective of the AUG programme is to shed light on the underlying physics of confinement, stability, and plasma exhaust in order to allow reliable extrapolation of results obtained on present day machines to these reactor-grade devices. Concerning pedestal physics, the mitigation of edge localised modes (ELMs) using resonant magnetic perturbations (RMPs) was found to be consistent with a reduction of the linear peeling-ballooning stability threshold due to the helical deformation of the plasma. Conversely, ELM suppression by RMPs is ascribed to an increased pedestal transport that keeps the plasma away from this boundary. Candidates for this increased transport are locally enhanced turbulence and a locked magnetic island in the pedestal. The enhanced D-alpha (EDA) and quasi-continuous exhaust (QCE) regimes have been established as promising ELM-free scenarios. Here, the pressure gradient at the foot of the H-mode pedestal is reduced by a quasi-coherent mode, consistent with violation of the high-n ballooning mode stability limit there. This is suggestive that the EDA and QCE regimes have a common underlying physics origin. In the area of transport physics, full radius models for both L- and H-modes have been developed. These models predict energy confinement in AUG better than the commonly used global scaling laws, representing a large step towards the goal of predictive capability. A new momentum transport analysis framework has been developed that provides access to the intrinsic torque in the plasma core. In the field of exhaust, the X-Point Radiator (XPR), a cold and dense plasma region on closed flux surfaces close to the X-point, was described by an analytical model that provides an understanding of its formation as well as its stability, i.e., the conditions under which it transitions into a deleterious MARFE with the potential to result in a disruptive termination. With the XPR close to the divertor target, a new detached divertor concept, the compact radiative divertor, was developed. Here, the exhaust power is radiated before reaching the target, allowing close proximity of the X-point to the target. No limitations by the shallow field line angle due to the large flux expansion were observed, and sufficient compression of neutral density was demonstrated. With respect to the pumping of non-recycling impurities, the divertor enrichment was found to mainly depend on the ionisation energy of the impurity under consideration. In the area of MHD physics, analysis of the hot plasma core motion in sawtooth crashes showed good agreement with nonlinear 2-fluid simulations. This indicates that the fast reconnection observed in these events is adequately described including the pressure gradient and the electron inertia in the parallel Ohm’s law. Concerning disruption physics, a shattered pellet injection system was installed in collaboration with the ITER International Organisation. Thanks to the ability to vary the shard size distribution independently of the injection velocity, as well as its impurity admixture, it was possible to tailor the current quench rate, which is an important requirement for future large devices such as ITER. Progress was also made modelling the force reduction of VDEs induced by massive gas injection on AUG. The H-mode density limit was characterised in terms of safe operational space with a newly developed active feedback control method that allowed the stability boundary to be probed several times within a single discharge without inducing a disruptive termination. Regarding integrated operation scenarios, the role of density peaking in the confinement of the ITER baseline scenario (high plasma current) was clarified. The usual energy confinement scaling ITER98( p,y ) does not capture this effect, but the more recent H20 scaling does, highlighting again the importance of developing adequate physics based models. Advanced tokamak scenarios, aiming at large non-inductive current fraction due to non-standard profiles of the safety factor in combination with high normalised plasma pressure were studied with a focus on their access conditions. A method to guide the approach of the targeted safety factor profiles was developed, and the conditions for achieving good confinement were clarified. Based on this, two types of advanced scenarios (‘hybrid’ and ‘elevated’ q -profile) were established on AUG and characterised concerning their plasma performance.
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- 2024
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40. Overview of the EUROfusion Tokamak Exploitation programme in support of ITER and DEMO
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E. Joffrin, M. Wischmeier, M. Baruzzo, A. Hakola, A. Kappatou, D. Keeling, B. Labit, E. Tsitrone, N. Vianello, the ASDEX Upgrade Team, JET Contributors, the MAST-U Team, the TCV Team, the WEST Team, the EUROfusion Tokamak Exploitation Team:, D. Abate, J. Adamek, M. Agostini, C. Albert, F.C.P. Albert Devasagayam, S. Aleiferis, E. Alessi, J. Alhage, S. Allan, J. Allcock, M. Alonzo, G. Anastasiou, E. Andersson Sunden, C. Angioni, Y. Anquetin, L. Appel, G.M. Apruzzese, M. Ariola, C. Arnas, J.F. Artaud, W. Arter, O. Asztalos, L. Aucone, M.H. Aumeunier, F. Auriemma, J. Ayllon, E. Aymerich, A. Baciero, F. Bagnato, L. Bähner, F. Bairaktaris, P. Balázs, L. Balbinot, I. Balboa, M. Balden, A. Balestri, M. Baquero Ruiz, T. Barberis, C. Barcellona, O. Bardsley, S. Benkadda, T. Bensadon, E. Bernard, M. Bernert, H. Betar, R. Bianchetti Morales, J. Bielecki, R. Bilato, P. Bilkova, W. Bin, G. Birkenmeier, R. Bisson, P. Blanchard, A. Bleasdale, V. Bobkov, A. Boboc, A. Bock, K. Bogar, P. Bohm, T. Bolzonella, F. Bombarda, N. Bonanomi, L. Boncagni, D. Bonfiglio, R. Bonifetto, M. Bonotto, D. Borodin, I. Borodkina, T.O.S.J. Bosman, C. Bourdelle, C. Bowman, S. Brezinsek, D. Brida, F. Brochard, R. Brunet, D. Brunetti, V. Bruno, R. Buchholz, J. Buermans, H. Bufferand, P. Buratti, A. Burckhart, J. Cai, R. Calado, J. Caloud, S. Cancelli, F. Cani, B. Cannas, M. Cappelli, S. Carcangiu, A. Cardinali, S. Carli, D. Carnevale, M. Carole, M. Carpita, D. Carralero, F. Caruggi, I.S. Carvalho, I. Casiraghi, A. Casolari, F.J. Casson, C. Castaldo, A. Cathey, F. Causa, J. Cavalier, M. Cavedon, J. Cazabonne, M. Cecconello, L. Ceelen, A. Celora, J. Cerovsky, C.D. Challis, R. Chandra, A. Chankin, B. Chapman, H. Chen, M. Chernyshova, A.G. Chiariello, P. Chmielewski, A. Chomiczewska, C. Cianfarani, G. Ciraolo, J. Citrin, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, I.H. Coffey, C. Colandrea, L. Colas, S. Conroy, C. Contre, N.J. Conway, L. Cordaro, Y. Corre, D. Costa, S. Costea, D. Coster, X. Courtois, C. Cowley, T. Craciunescu, G. Croci, A.M. Croitoru, K. Crombe, D.J. Cruz Zabala, G. Cseh, T. Czarski, A. Da Ros, A. Dal Molin, M. Dalla Rosa, Y. Damizia, O. D’Arcangelo, P. David, M. De Angeli, E. De la Cal, E. De La Luna, G. De Tommasi, J. Decker, R. Dejarnac, D. Del Sarto, G. Derks, C. Desgranges, P. Devynck, S. Di Genova, L.E. di Grazia, A. Di Siena, M. Dicorato, M. Diez, M. Dimitrova, T. Dittmar, L. Dittrich, J.J. Domínguez Palacios Durán, P. Donnel, D. Douai, S. Dowson, S. Doyle, M. Dreval, P. Drews, L. Dubus, R. Dumont, D. Dunai, M. Dunne, A. Durif, F. Durodie, G. Durr Legoupil Nicoud, B. Duval, R. Dux, T. Eich, A. Ekedahl, S. Elmore, G. Ericsson, J. Eriksson, B. Eriksson, F. Eriksson, S. Ertmer, A. Escarguel, B. Esposito, T. Estrada, E. Fable, M. Faitsch, N. Fakhrayi Mofrad, A. Fanni, T. Farley, M. Farník, N. Fedorczak, F. Felici, X. Feng, J. Ferreira, D. Ferreira, N. Ferron, O. Fevrier, O. Ficker, A.R. Field, A. Figueiredo, N. Fil, D. Fiorucci, M. Firdaouss, R. Fischer, M. Fitzgerald, M. Flebbe, M. Fontana, J. Fontdecaba Climent, A. Frank, E. Fransson, L. Frassinetti, D. Frigione, S. Futatani, R. Futtersack, S. Gabriellini, D. Gadariya, D. Galassi, K. Galazka, J. Galdon, S. Galeani, D. Gallart, A. Gallo, C. Galperti, M. Gambrioli, S. Garavaglia, J. Garcia, M. Garcia Munoz, J. Gardarein, L. Garzotti, J. Gaspar, R. Gatto, P. Gaudio, M. Gelfusa, J. Gerardin, S.N. Gerasimov, R. Gerru Miguelanez, G. Gervasini, Z. Ghani, F.M. Ghezzi, G. Ghillardi, L. Giannone, S. Gibson, L. Gil, A. Gillgren, E. Giovannozzi, C. Giroud, G. Giruzzi, T. Gleiter, M. Gobbin, V. Goloborodko, A. González Ganzábal, T. Goodman, V. Gopakumar, G. Gorini, T. Görler, S. Gorno, G. Granucci, D. Greenhouse, G. Grenfell, M. Griener, W. Gromelski, M. Groth, O. Grover, M. Gruca, A. Gude, C. Guillemaut, R. Guirlet, J. Gunn, T. Gyergyek, L. Hagg, J. Hall, C.J. Ham, M. Hamed, T. Happel, G. Harrer, J. Harrison, D. Harting, N.C. Hawkes, P. Heinrich, S. Henderson, P. Hennequin, R. Henriques, S. Heuraux, J. Hidalgo Salaverri, J. Hillairet, J.C. Hillesheim, A. Hjalmarsson, A. Ho, J. Hobirk, E. Hodille, M. Hölzl, M. Hoppe, J. Horacek, N. Horsten, L. Horvath, M. Houry, K. Hromasova, J. Huang, Z. Huang, A. Huber, E. Huett, P. Huynh, A. Iantchenko, M. Imrisek, P. Innocente, C. Ionita Schrittwieser, H. Isliker, P. Ivanova, I. Ivanova Stanik, M. Jablczynska, S. Jachmich, A.S. Jacobsen, P. Jacquet, A. Jansen van Vuuren, A. Jardin, H. Järleblad, A. Järvinen, F. Jaulmes, T. Jensen, I. Jepu, S. Jessica, T. Johnson, A. Juven, J. Kalis, J. Karhunen, R. Karimov, A.N. Karpushov, S. Kasilov, Y. Kazakov, P.V. Kazantzidis, W. Kernbichler, HT. Kim, D.B. King, V.G. Kiptily, A. Kirjasuo, K.K. Kirov, A. Kirschner, A. Kit, T. Kiviniemi, F. Kjær, E. Klinkby, A. Knieps, U. Knoche, M. Kochan, F. Köchl, G. Kocsis, J.T.W. Koenders, L. Kogan, Y. Kolesnichenko, Y. Kominis, M. Komm, M. Kong, B. Kool, S.B. Korsholm, D. Kos, M. Koubiti, J. Kovacic, Y. Kovtun, E. Kowalska Strzeciwilk, K. Koziol, M. Kozulia, A. Krämer Flecken, A. Kreter, K. Krieger, U. Kruezi, O. Krutkin, O. Kudlacek, U. Kumar, H. Kumpulainen, M.H. Kushoro, R. Kwiatkowski, M. La Matina, M. Lacquaniti, L. Laguardia, P. Lainer, P. Lang, M. Larsen, E. Laszynska, K.D. Lawson, A. Lazaros, E. Lazzaro, M.Y.K. Lee, S. Leerink, M. Lehnen, M. Lennholm, E. Lerche, Y. Liang, A. Lier, J. Likonen, O. Linder, B. Lipschultz, A. Listopad, X. Litaudon, E. Litherland Smith, D. Liuzza, T. Loarer, P.J. Lomas, J. Lombardo, N. Lonigro, R. Lorenzini, C. Lowry, T. Luda di Cortemiglia, A. Ludvig Osipov, T. Lunt, V. Lutsenko, E. Macusova, R. Mäenpää, P. Maget, C.F. Maggi, J. Mailloux, S. Makarov, K. Malinowski, P. Manas, A. Mancini, D. Mancini, P. Mantica, M. Mantsinen, J. Manyer, M. Maraschek, G. Marceca, G. Marcer, C. Marchetto, S. Marchioni, A. Mariani, M. Marin, M. Markl, T. Markovic, D. Marocco, S. Marsden, L. Martellucci, P. Martin, C. Martin, F. Martinelli, L. Martinelli, J.R. Martin Solis, R. Martone, M. Maslov, R. Masocco, M. Mattei, G.F. Matthews, D. Matveev, E. Matveeva, M.L. Mayoral, D. Mazon, S. Mazzi, C. Mazzotta, G. McArdle, R. McDermott, K. McKay, A.G. Meigs, C. Meineri, A. Mele, V. Menkovski, S. Menmuir, A. Merle, H. Meyer, K. Mikszuta Michalik, D. Milanesio, F. Militello, A. Milocco, I.G. Miron, J. Mitchell, R. Mitteau, V. Mitterauer, J. Mlynar, V. Moiseenko, P. Molna, F. Mombelli, C. Monti, A. Montisci, J. Morales, P. Moreau, J.M. Moret, A. Moro, D. Moulton, P. Mulholland, M. Muraglia, A. Murari, A. Muraro, P. Muscente, D. Mykytchuk, F. Nabais, Y. Nakeva, F. Napoli, E. Nardon, M.F. Nave, R.D. Nem, A. Nielsen, S.K. Nielsen, M. Nocente, R. Nouailletas, S. Nowak, H. Nyström, R. Ochoukov, N. Offeddu, S. Olasz, C. Olde, F. Oliva, D. Oliveira, H.J.C. Oliver, P. Ollus, J. Ongena, F.P. Orsitto, N. Osborne, R. Otin, P. Oyola Dominguez, D.I. Palade, S. Palomba, O. Pan, N. Panadero, E. Panontin, A. Papadopoulos, P. Papagiannis, G. Papp, V.V. Parail, C. Pardanaud, J. Parisi, A. Parrott, K. Paschalidis, M. Passoni, F. Pastore, A. Patel, B. Patel, A. Pau, G. Pautasso, R. Pavlichenko, E. Pawelec, B. Pegourie, G. Pelka, E. Peluso, A. Perek, E. Perelli Cippo, C. Perez Von Thun, P. Petersson, G. Petravich, Y. Peysson, V. Piergotti, L. Pigatto, C. Piron, L. Piron, A. Pironti, F. Pisano, U. Plank, B. Ploeckl, V. Plyusnin, A. Podolnik, Y. Poels, G. Pokol, J. Poley, G. Por, M. Poradzinski, F. Porcelli, L. Porte, C. Possieri, A. Poulsen, I. Predebon, G. Pucella, M. Pueschel, P. Puglia, O. Putignano, T. Pütterich, V. Quadri, A. Quercia, M. Rabinski, L. Radovanovic, R. Ragona, H. Raj, M. Rasinski, J. Rasmussen, G. Ratta, S. Ratynskaia, R. Rayaprolu, M. Rebai, A. Redl, D. Rees, D. Refy, M. Reich, H. Reimerdes, B.C.G. Reman, O. Renders, C. Reux, D. Ricci, M. Richou, S. Rienacker, D. Rigamonti, F. Rigollet, F.G. Rimini, D. Ripamonti, N. Rispoli, N. Rivals, J.F. Rivero Rodriguez, C. Roach, G. Rocchi, S. Rode, P. Rodrigues, J. Romazanov, C.F. Romero Madrid, J. Rosato, R. Rossi, G. Rubino, J. Rueda Rueda, J. Ruiz Ruiz, P. Ryan, D. Ryan, S. Saarelma, R. Sabot, M. Salewski, A. Salmi, L. Sanchis, A. Sand, J. Santos, K. Särkimäki, M. Sassano, O. Sauter, G. Schettini, S. Schmuck, P. Schneider, N. Schoonheere, R. Schramm, R. Schrittwieser, C. Schuster, N. Schwarz, F. Sciortino, M. Scotto D’Abusco, S. Scully, A. Selce, L. Senni, M. Senstius, G. Sergienko, S.E. Sharapov, R. Sharma, A. Shaw, U. Sheikh, G. Sias, B. Sieglin, S.A. Silburn, C. Silva, A. Silva, D. Silvagni, B. Simmendefeldt Schmidt, L. Simons, J. Simpson, L. Singh, S. Sipilä, Y. Siusko, S. Smith, A. Snicker, E.R. Solano, V. Solokha, M. Sos, C. Sozzi, F. Spineanu, G. Spizzo, M. Spolaore, L. Spolladore, C. Srinivasan, A. Stagni, Z. Stancar, G. Stankunas, J. Stober, P. Strand, C.I. Stuart, F. Subba, G.Y. Sun, H.J. Sun, W. Suttrop, J. Svoboda, T. Szepesi, G. Szepesi, B. Tal, T. Tala, P. Tamain, G. Tardini, M. Tardocchi, D. Taylor, G. Telesca, A. Tenaglia, A. Terra, D. Terranova, D. Testa, C. Theiler, E. Tholerus, B. Thomas, E. Thoren, A. Thornton, A. Thrysoe, Q. TICHIT, W. Tierens, A. Titarenko, P. Tolias, E. Tomasina, M. Tomes, E. Tonello, A. Tookey, M. Toscano Jiménez, C. Tsironis, C. Tsui, A. Tykhyy, M. Ugoletti, M. Usoltseva, D.F. Valcarcel, A. Valentini, M. Valisa, M. Vallar, M. Valovic, SI. Valvis, M. van Berkel, D. Van Eester, S. Van Mulders, M. van Rossem, R. Vann, B. Vanovac, J. Varela Rodriguez, J. Varje, S. Vartanian, M. Vecsei, L. Velarde Gallardo, M. Veranda, T. Verdier, G. Verdoolaege, K. Verhaegh, L. Vermare, G. Verona Rinati, J. Vicente, E. Viezzer, L. Vignitchouk, F. Villone, B. Vincent, P. Vincenzi, M.O. Vlad, G. Vogel, I. Voitsekhovitch, I. Voldiner, P. Vondracek, N.M.T. VU, T. Vuoriheimo, C. Wade, E. Wang, T. Wauters, M. Weiland, H. Weisen, N. Wendler, D. Weston, A. Widdowson, S. Wiesen, M. Wiesenberger, T. Wijkamp, M. Willensdorfer, T. Wilson, A. Wojenski, C. Wuethrich, I. Wyss, L. Xiang, S. Xu, D. Yadykin, Y. Yakovenko, H. Yang, V. Yanovskiy, R. Yi, B. Zaar, G. Zadvitskiy, L. Zakharov, P. Zanca, D. Zarzoso, Y. Zayachuk, J. Zebrowski, M. Zerbini, P. Zestanakis, C. F. B. Zimmermann, M. Zlobinski, A. Zohar, V.K. Zotta, X. Zou, M. Zuin, M. Zurita, and I. Zychor
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JET ,ASDEX Upgrade ,MAST-U ,TCV ,WEST ,Tokamak Exploitation Task Force ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under the auspices of a single Task Force called ‘Tokamak Exploitation’. The goal is to benefit from the complementary capabilities of each machine in a coordinated way and help in developing a scientific output scalable to future largre machines. The programme of this Task Force ensures that ASDEX Upgrade, MAST-U, TCV, WEST and JET (since 2022) work together to achieve the objectives of Missions 1 and 2 of the EUROfusion Roadmap: i) demonstrate plasma scenarios that increase the success margin of ITER and satisfy the requirements of DEMO and, ii) demonstrate an integrated approach that can handle the large power leaving ITER and DEMO plasmas. The Tokamak Exploitation task force has therefore organized experiments on these two missions with the goal to strengthen the physics and operational basis for the ITER baseline scenario and for exploiting the recent plasma exhaust enhancements in all four devices (PEX: Plasma EXhaust) for exploring the solution for handling heat and particle exhaust in ITER and develop the conceptual solutions for DEMO. The ITER Baseline scenario has been developed in a similar way in ASDEX Upgrade, TCV and JET. Key risks for ITER such as disruptions and run-aways have been also investigated in TCV, ASDEX Upgrade and JET. Experiments have explored successfully different divertor configurations (standard, super-X, snowflakes) in MAST-U and TCV and studied tungsten melting in WEST and ASDEX Upgrade. The input from the smaller devices to JET has also been proven successful to set-up novel control schemes on disruption avoidance and detachment.
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- 2024
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41. Overview of T and D–T results in JET with ITER-like wall
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C.F. Maggi, D. Abate, N. Abid, P. Abreu, O. Adabonyan, M. Afzal, I. Ahmad, M. Akhtar, R. Albanese, S. Aleiferis, E. Alessi, P. Aleynikov, J. Alguacil, J. Alhage, M. Ali, H. Allen, M. Allinson, M. Alonzo, E. Alves, R. Ambrosino, E. Andersson Sundén, P. Andrew, M. Angelone, C. Angioni, I. Antoniou, L. Appel, C. Appelbee, C. Aramunde, M. Ariola, G. Arnoux, G. Artaserse, J.-F. Artaud, W. Arter, V. Artigues, F.J. Artola, A. Ash, O. Asztalos, D. Auld, F. Auriemma, Y. Austin, L. Avotina, J. Ayllón, E. Aymerich, A. Baciero, L. Bähner, F. Bairaktaris, I. Balboa, M. Balden, N. Balshaw, V.K. Bandaru, J. Banks, A. Banon Navarro, C. Barcellona, O. Bardsley, M. Barnes, R. Barnsley, M. Baruzzo, M. Bassan, A. Batista, P. Batistoni, L. Baumane, B. Bauvir, L. Baylor, C. Bearcroft, P. Beaumont, D. Beckett, A. Begolli, M. Beidler, N. Bekris, M. Beldishevski, E. Belli, F. Belli, S. Benkadda, J. Bentley, E. Bernard, J. Bernardo, M. Bernert, M. Berry, L. Bertalot, H. Betar, M. Beurskens, P.G. Bhat, S. Bickerton, J. Bielecki, T. Biewer, R. Bilato, P. Bílková, G. Birkenmeier, R. Bisson, J.P.S. Bizarro, P. Blatchford, A. Bleasdale, V. Bobkov, A. Boboc, A. Bock, G. Bodnar, P. Bohm, L. Bonalumi, N. Bonanomi, D. Bonfiglio, X. Bonnin, P. Bonofiglo, J. Booth, D. Borba, D. Borodin, I. Borodkina, T.O.S.J. Bosman, C. Bourdelle, M. Bowden, I. Božičević Mihalić, S.C. Bradnam, B. Breizman, S. Brezinsek, D. Brida, M. Brix, P. Brown, D. Brunetti, M. Buckley, J. Buermans, H. Bufferand, P. Buratti, A. Burckhart, A. Burgess, A. Buscarino, A. Busse, D. Butcher, G. Calabrò, L. Calacci, R. Calado, R. Canavan, B. Cannas, M. Cannon, M. Cappelli, S. Carcangiu, P. Card, A. Cardinali, S. Carli, P. Carman, D. Carnevale, B. Carvalho, I.S. Carvalho, P. Carvalho, I. Casiraghi, F.J. Casson, C. Castaldo, J.P. Catalan, N. Catarino, F. Causa, M. Cavedon, M. Cecconello, L. Ceelen, C.D. Challis, B. Chamberlain, R. Chandra, C.S. Chang, A. Chankin, B. Chapman, P. Chauhan, M. Chernyshova, A. Chiariello, G.-C. Chira, P. Chmielewski, A. Chomiczewska, L. Chone, J. Cieslik, G. Ciraolo, D. Ciric, J. Citrin, Ł. Ciupinski, R. Clarkson, M. Cleverly, P. Coates, V. Coccorese, R. Coelho, J.W. Coenen, I.H. Coffey, A. Colangeli, L. Colas, J. Collins, S. Conroy, C. Contré, N.J. Conway, D. Coombs, P. Cooper, S. Cooper, L. Cordaro, C. Corradino, Y. Corre, G. Corrigan, D. Coster, T. Craciunescu, S. Cramp, D. Craven, R. Craven, G. Croci, D. Croft, K. Crombé, T. Cronin, N. Cruz, A. Cufar, A. Cullen, A. Dal Molin, S. Dalley, P. David, A. Davies, J. Davies, S. Davies, G. Davis, K. Dawson, S. Dawson, I. Day, G. De Tommasi, J. Deane, M. Dearing, M. De Bock, J. Decker, R. Dejarnac, E. Delabie, E. de la Cal, E. de la Luna, D. Del Sarto, A. Dempsey, W. Deng, A. Dennett, G.L. Derks, G. De Temmerman, F. Devasagayam, P. de Vries, P. Devynck, A. di Siena, D. Dickinson, T. Dickson, M. Diez, P. Dinca, T. Dittmar, L. Dittrich, J. Dobrashian, T. Dochnal, A.J.H. Donné, W. Dorland, S. Dorling, S. Dormido-Canto, R. Dotse, D. Douai, S. Dowson, R. Doyle, M. Dreval, P. Drews, G. Drummond, Ph. Duckworth, H.G. Dudding, R. Dumont, P. Dumortier, D. Dunai, T. Dunatov, M. Dunne, I. Ďuran, F. Durodié, R. Dux, T. Eade, E. Eardley, J. Edwards, T. Eich, A. Eksaeva, H. El-Haroun, R.D. Ellis, G. Ellwood, C. Elsmore, S. Emery, G. Ericsson, B. Eriksson, F. Eriksson, J. Eriksson, L.G. Eriksson, S. Ertmer, G. Evans, S. Evans, E. Fable, D. Fagan, M. Faitsch, D. Fajardo Jimenez, M. Falessi, A. Fanni, T. Farmer, I. Farquhar, B. Faugeras, S. Fazinić, N. Fedorczak, K. Felker, R. Felton, H. Fernandes, D.R. Ferreira, J. Ferreira, G. Ferrò, J. Fessey, O. Février, O. Ficker, A.R. Field, A. Figueiredo, J. Figueiredo, A. Fil, N. Fil, P. Finburg, U. Fischer, G. Fishpool, L. Fittill, M. Fitzgerald, D. Flammini, J. Flanagan, S. Foley, N. Fonnesu, M. Fontana, J.M. Fontdecaba, L. Fortuna, E. Fortuna-Zalesna, M. Fortune, C. Fowler, P. Fox, O. Franklin, E. Fransson, L. Frassinetti, R. Fresa, D. Frigione, T. Fülöp, M. Furseman, S. Gabriellini, D. Gadariya, S. Gadgil, K. Gál, S. Galeani, A. Galkowski, D. Gallart, M. Gambrioli, T. Gans, J. Garcia, M. García-Muñoz, L. Garzotti, J. Gaspar, R. Gatto, P. Gaudio, D. Gear, T. Gebhart, S. Gee, M. Gelfusa, R. George, S.N. Gerasimov, R. Gerru, G. Gervasini, M. Gethins, Z. Ghani, M. Gherendi, P.-I. Gherghina, F. Ghezzi, L. Giacomelli, C. Gibson, L. Gil, M.R. Gilbert, A. Gillgren, E. Giovannozzi, C. Giroud, G. Giruzzi, J. Goff, V. Goloborodko, R. Gomes, J.-F. Gomez, B. Gonçalves, M. Goniche, J. Gonzalez-Martin, A. Goodyear, S. Gore, G. Gorini, T. Görler, N. Gotts, E. Gow, J.P. Graves, J. Green, H. Greuner, E. Grigore, F. Griph, W. Gromelski, M. Groth, C. Grove, R. Grove, N. Gupta, S. Hacquin, L. Hägg, A. Hakola, M. Halitovs, J. Hall, C.J. Ham, M. Hamed, M.R. Hardman, Y. Haresawa, G. Harrer, J.R. Harrison, D. Harting, D.R. Hatch, T. Haupt, J. Hawes, N.C. Hawkes, J. Hawkins, S. Hazael, J. Hearmon, P. Heesterman, P. Heinrich, M. Held, W. Helou, O. Hemming, S.S. Henderson, R. Henriques, R.B. Henriques, D. Hepple, J. Herfindal, G. Hermon, J.C. Hillesheim, K. Hizanidis, A. Hjalmarsson, A. Ho, J. Hobirk, O. Hoenen, C. Hogben, A. Hollingsworth, S. Hollis, E. Hollmann, M. Hölzl, M. Hook, M. Hoppe, J. Horáček, N. Horsten, A. Horton, L.D. Horton, L. Horvath, S. Hotchin, Z. Hu, Z. Huang, E. Hubenov, A. Huber, V. Huber, T. Huddleston, G.T.A. Huijsmans, Y. Husain, P. Huynh, A. Hynes, D. Iglesias, M.V. Iliasova, M. Imríšek, J. Ingleby, P. Innocente, V. Ioannou-Sougleridis, N. Isernia, I. Ivanova-Stanik, E. Ivings, S. Jachmich, T. Jackson, A.S. Jacobsen, P. Jacquet, H. Järleblad, A. Järvinen, F. Jaulmes, N. Jayasekera, F. Jenko, I. Jepu, E. Joffrin, T. Johnson, J. Johnston, C. Jones, E. Jones, G. Jones, L. Jones, T.T.C. Jones, A. Joyce, M. Juvonen, A. Kallenbach, P. Kalnina, D. Kalupin, P. Kanth, A. Kantor, A. Kappatou, O. Kardaun, J. Karhunen, E. Karsakos, Ye.O. Kazakov, V. Kazantzidis, D.L. Keeling, W. Kelly, M. Kempenaars, D. Kennedy, K. Khan, E. Khilkevich, C. Kiefer, H.-T. Kim, J. Kim, S.H. Kim, D.B. King, D.J. Kinna, V.G. Kiptily, A. Kirjasuo, K.K. Kirov, A. Kirschner, T. Kiviniemi, G. Kizane, C. Klepper, A. Klix, G. Kneale, M. Knight, P. Knight, R. Knights, S. Knipe, U. Knoche, M. Knolker, M. Kocan, F. Köchl, G. Kocsis, J.T.W. Koenders, Y. Kolesnichenko, Y. Kominis, M. Kong, B. Kool, V. Korovin, S.B. Korsholm, B. Kos, D. Kos, M. Koubiti, Y. Kovtun, E. Kowalska-Strzęciwilk, K. Koziol, Y. Krasikov, A. Krasilnikov, V. Krasilnikov, M. Kresina, A. Kreter, K. Krieger, A. Krivska, U. Kruezi, I. Książek, H. Kumpulainen, B. Kurzan, S. Kwak, O.J. Kwon, B. Labit, M. Lacquaniti, A. Lagoyannis, L. Laguardia, A. Laing, V. Laksharam, N. Lam, H.T. Lambertz, B. Lane, M. Langley, E. Lascas Neto, E. Łaszyńska, K.D. Lawson, A. Lazaros, E. Lazzaro, G. Learoyd, C. Lee, K. Lee, S. Leerink, T. Leeson, X. Lefebvre, H.J. Leggate, J. Lehmann, M. Lehnen, D. Leichtle, F. Leipold, I. Lengar, M. Lennholm, E. Leon Gutierrez, L.A. Leppin, E. Lerche, A. Lescinskis, S. Lesnoj, L. Lewin, J. Lewis, J. Likonen, Ch. Linsmeier, X. Litaudon, E. Litherland-Smith, F. Liu, T. Loarer, A. Loarte, R. Lobel, B. Lomanowski, P.J. Lomas, J. Lombardo, R. Lorenzini, S. Loreti, V.P. Loschiavo, M. Loughlin, T. Lowe, C. Lowry, T. Luce, R. Lucock, T. Luda Di Cortemiglia, M. Lungaroni, C.P. Lungu, T. Lunt, V. Lutsenko, B. Lyons, J. Macdonald, E. Macusova, R. Mäenpää, H. Maier, J. Mailloux, S. Makarov, P. Manas, A. Manning, P. Mantica, M.J. Mantsinen, J. Manyer, A. Manzanares, Ph. Maquet, M. Maraschek, G. Marceca, G. Marcer, C. Marchetto, O. Marchuk, A. Mariani, G. Mariano, M. Marin, A. Marin Roldan, M. Marinelli, T. Markovič, L. Marot, C. Marren, S. Marsden, S. Marsen, J. Marsh, R. Marshall, L. Martellucci, A.J. Martin, C. Martin, R. Martone, S. Maruyama, M. Maslov, M. Mattei, G.F. Matthews, D. Matveev, E. Matveeva, A. Mauriya, F. Maviglia, M. Mayer, M.-L. Mayoral, S. Mazzi, C. Mazzotta, R. McAdams, P.J. McCarthy, P. McCullen, R. McDermott, D.C. McDonald, D. McGuckin, V. McKay, L. McNamee, A. McShee, D. Mederick, M. Medland, S. Medley, K. Meghani, A.G. Meigs, S. Meitner, S. Menmuir, K. Mergia, S. Mianowski, P. Middleton, J. Mietelski, K. Mikszuta-Michalik, D. Milanesio, E. Milani, E. Militello-Asp, F. Militello, J. Milnes, A. Milocco, S. Minucci, I. Miron, J. Mitchell, J. Mlynář, V. Moiseenko, P. Monaghan, I. Monakhov, A. Montisci, S. Moon, R. Mooney, S. Moradi, R.B. Morales, L. Morgan, F. Moro, J. Morris, T. Mrowetz, L. Msero, S. Munot, A. Muñoz-Perez, M. Muraglia, A. Murari, A. Muraro, B. N’Konga, Y.S. Na, F. Nabais, R. Naish, F. Napoli, E. Nardon, V. Naulin, M.F.F. Nave, R. Neu, S. Ng, M. Nicassio, D. Nicolai, A.H. Nielsen, S.K. Nielsen, D. Nina, C. Noble, C.R. Nobs, M. Nocente, H. Nordman, S. Nowak, H. Nyström, J. O’Callaghan, M. O’Mullane, C. O’Neill, C. Olde, H.J.C. Oliver, R. Olney, J. Ongena, G.P. Orsitto, A. Osipov, R. Otin, N. Pace, L.W. Packer, E. Pajuste, D. Palade, J. Palgrave, O. Pan, N. Panadero, T. Pandya, E. Panontin, A. Papadopoulos, G. Papadopoulos, G. Papp, V.V. Parail, A. Parsloe, K. Paschalidis, M. Passeri, A. Patel, A. Pau, G. Pautasso, R. Pavlichenko, A. Pavone, E. Pawelec, C. Paz-Soldan, A. Peacock, M. Pearce, I.J. Pearson, E. Peluso, C. Penot, K. Pepperell, A. Perdas, T. Pereira, E. Perelli Cippo, C. Perez von Thun, D. Perry, P. Petersson, G. Petravich, N. Petrella, M. Peyman, L. Pigatto, M. Pillon, S. Pinches, G. Pintsuk, C. Piron, A. Pironti, F. Pisano, R. Pitts, U. Planck, N. Platt, V. Plyusnin, M. Podesta, G. Pokol, F.M. Poli, O.G. Pompilian, M. Poradzinski, M. Porkolab, C. Porosnicu, G. Poulipoulis, A.S. Poulsen, I. Predebon, A. Previti, D. Primetzhofer, G. Provatas, G. Pucella, P. Puglia, K. Purahoo, O. Putignano, T. Pütterich, A. Quercia, G. Radulescu, V. Radulovic, R. Ragona, M. Rainford, P. Raj, M. Rasinski, D. Rasmussen, J. Rasmussen, J.J. Rasmussen, A. Raso, G. Rattá, S. Ratynskaia, R. Rayaprolu, M. Rebai, A. Redl, D. Rees, D. Réfy, R. Reichle, H. Reimerdes, B.C.G. Reman, C. Reux, S. Reynolds, D. Rigamonti, E. Righi, F.G. Rimini, J. Risner, J.F. Rivero-Rodriguez, C.M. Roach, J. Roberts, R. Robins, S. Robinson, D. Robson, S. Rode, P. Rodrigues, P. Rodriguez-Fernandez, S. Romanelli, J. Romazanov, E. Rose, C. Rose-Innes, R. Rossi, S. Rowe, D. Rowlands, C. Rowley, M. Rubel, G. Rubinacci, G. Rubino, M. Rud, J. Ruiz Ruiz, F. Ryter, S. Saarelma, A. Sahlberg, M. Salewski, A. Salmi, R. Salmon, F. Salzedas, F. Sanchez, I. Sanders, D. Sandiford, F. Sanni, O. Sauter, P. Sauvan, G. Schettini, A. Shevelev, A.A. Schekochihin, K. Schmid, B.S. Schmidt, S. Schmuck, M. Schneider, P.A. Schneider, N. Schoonheere, R. Schramm, D. Scoon, S. Scully, M. Segato, J. Seidl, L. Senni, J. Seo, G. Sergienko, M. Sertoli, S.E. Sharapov, R. Sharma, A. Shaw, R. Shaw, H. Sheikh, U. Sheikh, N. Shi, P. Shigin, D. Shiraki, G. Sias, M. Siccinio, B. Sieglin, S.A. Silburn, A. Silva, C. Silva, J. Silva, D. Silvagni, D. Simfukwe, J. Simpson, P. Sirén, A. Sirinelli, H. Sjöstrand, N. Skinner, J. Slater, T. Smart, R.D. Smirnov, N. Smith, P. Smith, T. Smith, J. Snell, L. Snoj, E.R. Solano, V. Solokha, C. Sommariva, K. Soni, M. Sos, J. Sousa, C. Sozzi, T. Spelzini, F. Spineanu, L. Spolladore, D. Spong, C. Srinivasan, G. Staebler, A. Stagni, I. Stamatelatos, M.F. Stamp, Ž. Štancar, P.A. Staniec, G. Stankūnas, M. Stead, B. Stein-Lubrano, A. Stephen, J. Stephens, P. Stevenson, C. Steventon, M. Stojanov, D.A. St-Onge, P. Strand, S. Strikwerda, C.I. Stuart, S. Sturgeon, H.J. Sun, S. Surendran, W. Suttrop, J. Svensson, J. Svoboda, R. Sweeney, G. Szepesi, M. Szoke, T. Tadić, B. Tal, T. Tala, P. Tamain, K. Tanaka, W. Tang, G. Tardini, M. Tardocchi, D. Taylor, A.S. Teimane, G. Telesca, A. Teplukhina, A. Terra, D. Terranova, N. Terranova, D. Testa, B. Thomas, V.K. Thompson, A. Thorman, A.S. Thrysoe, W. Tierens, R.A. Tinguely, A. Tipton, H. Todd, M. Tomeš, A. Tookey, P. Tsavalas, D. Tskhakaya, L.-P. Turică, A. Turner, I. Turner, M. Turner, M.M. Turner, G. Tvalashvili, A. Tykhyy, S. Tyrrell, A. Uccello, V. Udintsev, A. Vadgama, D.F. Valcarcel, A. Valentini, M. Valisa, M. Vallar, M. Valovic, M. Van Berkel, K.L. van de Plassche, M. van Rossem, D. Van Eester, J. Varela, J. Varje, T. Vasilopoulou, G. Vayakis, M. Vecsei, J. Vega, M. Veis, P. Veis, S. Ventre, M. Veranda, G. Verdoolaege, C. Verona, G. Verona Rinati, E. Veshchev, N. Vianello, E. Viezzer, L. Vignitchouk, R. Vila, R. Villari, F. Villone, P. Vincenzi, A. Vitins, Z. Vizvary, M. Vlad, I. Voldiner, U. Von Toussaint, P. Vondráček, B. Wakeling, M. Walker, R. Walker, M. Walsh, R. Walton, E. Wang, F. Warren, R. Warren, J. Waterhouse, C. Watts, T. Webster, M. Weiland, H. Weisen, M. Weiszflog, N. Wendler, A. West, M. Wheatley, S. Whetham, A. Whitehead, D. Whittaker, A. Widdowson, S. Wiesen, M. Willensdorfer, J. Williams, I. Wilson, T. Wilson, M. Wischmeier, A. Withycombe, D. Witts, A. Wojcik-Gargula, E. Wolfrum, R. Wood, R. Woodley, R. Worrall, I. Wyss, T. Xu, D. Yadykin, Y. Yakovenko, Y. Yang, V. Yanovskiy, R. Yi, I. Young, R. Young, B. Zaar, R.J. Zabolockis, L. Zakharov, P. Zanca, A. Zarins, D. Zarzoso Fernandez, K.-D. Zastrow, Y. Zayachuk, M. Zerbini, W. Zhang, B. Zimmermann, M. Zlobinski, A. Zocco, V.K. Zotta, M. Zuin, W. Zwingmann, and I. Zychor
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magnetic fusion ,JET-ILW ,D–T ,tritium ,alpha particles ,fusion prediction ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
In 2021 JET exploited its unique capabilities to operate with T and D–T fuel with an ITER-like Be/W wall (JET-ILW). This second major JET D–T campaign (DTE2), after DTE1 in 1997, represented the culmination of a series of JET enhancements—new fusion diagnostics, new T injection capabilities, refurbishment of the T plant, increased auxiliary heating, in-vessel calibration of 14 MeV neutron yield monitors—as well as significant advances in plasma theory and modelling in the fusion community. DTE2 was complemented by a sequence of isotope physics campaigns encompassing operation in pure tritium at high T-NBI power. Carefully conducted for safe operation with tritium, the new T and D–T experiments used 1 kg of T (vs 100 g in DTE1), yielding the most fusion reactor relevant D–T plasmas to date and expanding our understanding of isotopes and D–T mixture physics. Furthermore, since the JET T and DTE2 campaigns occurred almost 25 years after the last major D–T tokamak experiment, it was also a strategic goal of the European fusion programme to refresh operational experience of a nuclear tokamak to prepare staff for ITER operation. The key physics results of the JET T and DTE2 experiments, carried out within the EUROfusion JET1 work package, are reported in this paper. Progress in the technological exploitation of JET D–T operations, development and validation of nuclear codes, neutronic tools and techniques for ITER operations carried out by EUROfusion (started within the Horizon 2020 Framework Programme and continuing under the Horizon Europe FP) are reported in (Litaudon et al Nucl. Fusion accepted), while JET experience on T and D–T operations is presented in (King et al Nucl. Fusion submitted).
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- 2024
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42. First results of laser-induced desorption - quadrupole mass spectrometry (LID-QMS) at JET
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M. Zlobinski, G. Sergienko, I. Jepu, C. Rowley, A. Widdowson, R. Ellis, D. Kos, I. Coffey, M. Fortune, D. Kinna, M. Beldishevski, A. Krimmer, H.T. Lambertz, A. Terra, A. Huber, S. Brezinsek, T. Dittmar, M. Flebbe, R. Yi, R. Rayaprolu, J. Figueiredo, P. Blatchford, S. Silburn, E. Tsitrone, E. Joffrin, K. Krieger, Y. Corre, A. Hakola, J. Likonen, the Eurofusion Tokamak Exploitation Team, and JET Contributors
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fuel retention ,laser ,tritium ,deuterium ,desorption ,JET ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
The paper reports the first demonstration of in situ laser-induced desorption — quadrupole mass spectrometry (LID-QMS) application on a large scale fusion device performed in summer 2023. LID-QMS allows direct measurements of the fuel inventory of plasma facing components without retrieving them from the fusion device. The diagnostic desorbs the retained gases by heating a 3 mm diameter spot on the wall using a 1 ms long laser pulse and detects them by QMS. Thus, it can measure the gas content at any wall position accessible to the laser. The successful LID-QMS application in laboratory scale and on medium size fusion devices has now been demonstrated on the larger scale and it is already foreseen as tritium monitor diagnostic in ITER. This in situ diagnostic gives direct access to retention physics on a short timescale instead of campaign-integrated measurements and can assess the space-resolvedefficacy of detritation methods. LID-QMS can be applied on many materials: on Be deposits like in JET, B deposits like in TEXTOR, C based materials or on bulk-W.
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- 2024
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43. Investigations of atomic and molecular processes of NBI-heated discharges in the MAST Upgrade Super-X divertor with implications for reactors
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Kevin Verhaegh, James Harrison, Bruce Lipschultz, Nicola Lonigro, Stijn Kobussen, David Moulton, Nick Osborne, Peter Ryan, Christian Theiler, Tijs Wijkamp, Dominik Brida, Gijs Derks, Rhys Doyle, Fabio Federici, Antti Hakola, Stuart Henderson, Bob Kool, Sarah Newton, Ryoko Osawa, Xander Pope, Holger Reimerdes, Nicola Vianello, Marco Wischmeier, the EUROfusion Tokamak Exploitation Team, and the MAST-U Team
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MAST Upgrade ,Super-X divertor ,exhaust modelling ,divertor detachment ,plasma-molecular interactions ,collisional-radiative modelling ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
This experimental study presents an in-depth investigation of the performance of the MAST-U Super-X divertor during NBI-heated operation (up to 2.5 MW) focussing on volumetric ion sources and sinks as well as power losses during detachment. The particle balance and power loss analysis revealed the crucial role of Molecular Activated Recombination and Dissociation (MAR and MAD) ion sinks in divertor particle and power balance, which remain pronounced in the change from ohmic to higher power (NBI heated) L-mode conditions. The importance of MAR and MAD remains with double the absorbed NBI heating. MAD results in significant power dissipation (up to ${\sim} 20\%$ of $P_\textrm{SOL}$ ), mostly in the cold ( $T_e \lt 5$ eV) detached region. Theoretical and experimental evidence is found for the potential contribution of $D^-$ to MAR and MAD, which warrants further study. These results suggest that MAR and MAD can be relevant in higher power conditions than the ohmic conditions studied previously. Post-processing reactor-scale simulations suggests that MAR and MAD can play a significant role in divertor physics and synthetic diagnostic signals of reactor-scale devices, which are currently underestimated in exhaust simulations. This raises implications for the accuracy of reactor-scale divertor simulations of particularly tightly baffled (alternative) divertor configurations.
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- 2024
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44. Helium plasma operations on ASDEX Upgrade and JET in support of the non-nuclear phases of ITER
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A. Hakola, M. Balden, M. Baruzzo, R. Bisson, S. Brezinsek, T. Dittmar, D. Douai, M. Dunne, L. Garzotti, M. Groth, R. Henriques, L. Horvath, I. Jepu, E. Joffrin, A. Kappatou, D. Keeling, K. Krieger, B. Labit, M. Lennholm, J. Likonen, A. Loarte, P. Lomas, C. Lowry, M. Maslov, D. Matveev, R.A. Pitts, U. Plank, M. Rasinski, D. Ryan, S. Saarelma, S. Silburn, E.R. Solano, W. Suttrop, T. Tala, E. Tsitrone, N. Vianello, T. Wauters, A. Widdowson, M. Wischmeier, the EUROfusion Tokamak Exploitation Team, the ASDEX Upgrade Team, and JET Contributors
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helium plasma ,H-mode ,tungsten fuzz ,erosion ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
For its initial operational phase, ITER has until recently considered using non-nuclear hydrogen (H) or helium (He) plasmas to keep nuclear activation at low levels. To this end, the Tokamak Exploitation Task Force of the EUROfusion Consortium carried out dedicated experimental campaigns in He on the ASDEX Upgrade (AUG) and JET tokamaks in 2022, with particular emphasis put on the ELMy H-mode operation and plasma-wall interaction processes as well as comparison to H or deuterium (D) plasmas. Both in pure He and mixed He + H plasmas, H-mode operation could be reached but more effort was needed to obtain a stable plasma scenario than in H or D. Even if the power threshold for the LH transition was lower in He, entering the type-I ELMy regime appeared to require equally much or even more heating power than in H. Suppression of ELMs by resonant magnetic perturbations was studied on AUG but was only possible in plasmas with a He content below 19%; the reason for this unexpected behaviour remains still unclear and various theoretical approaches are being pursued to properly understand the physics behind ELM suppression. The erosion rates of tungsten (W) plasma-facing components were an order of magnitude larger than what has been reported in hydrogenic plasmas, which can be attributed to the prominent role of He ^2+ ions in the plasma. For the first time, the formation of nanoscale structures (W fuzz) was unambiguously demonstrated in H-mode He plasmas on AUG. However, no direct evidence of fuzz creation on JET was obtained despite the main conditions for its occurrence being met. The reason could be a delicate balance between W erosion by ELMs, competition between the growth and annealing of the fuzz, and coverage of the surface with co-deposits.
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- 2024
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45. JET machine operations in T&D-T
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The JET Operations Team (presented by D.B. King), E. Abdelrahman, A. Abdul Hamid, N. Abid, K. Abraham, O. Adabonyan, C. Adlam, M. Afzal, M. Akhtar, V. Aldred, S. Aldworth, S. Aleiferis, M. Ali, R. Alie, R. Allan, H. Allen, E. Alli, M. Allinson, P. Almond, J. Angus, K. Antcliffe, I. Antoniou, L. Appel, C. Appelbee, C. Aramunde, N. Archer, S. Aria, H. Arkuszynski, M. Arshad, G. Artaserse, A. Ash, C. Ashe, T. Aue, D. Auld, B. Austin, Y. Austin, C. Ayres, R.B. Morales, S. Baker, S. Bakes, I. Balboa, C. Balshaw, N. Balshaw, J. Banks, J. Banner, A. Barnard, M. Barnard, M. Baruzzo, C. Basagiannis, S. Bathe Hariyanandan, P. Batistoni, R. Baughan, P. Beaumont, D. Beckett, A. Begolli, M. Beldishevski, K. Bell, E. Belonohy, J. Bentley, J. Bernardo, M. Berry, J. Bhatt, S. Bickerton, J. Bielecki, W. Bird, D. Blackett, K. Blackman, S. Blake, P. Blatchford, A. Bleasdale, A. Boboc, J. Booth, P. Boulting, M. Bowden, C. Boyd, K. Boyd, R. Bracey, D. Brennan, A. Brett, M. Bright, M. Brix, I. Brooks, B. Brown, P. Brown, M. Brown, P. Brummitt, B. Viola, A. Buckingham, M. Buckley, J. Bumpass, M. Burford, A. Burgess, J. Burton-Sweeten, A. Busse, D. Butcher, P. Cahill, P. Camp, I. Campbell, R. Canavan, J. Cane, M. Cannon, N. Canterbury, A. Carberry, P. Card, M. Carlick, M. Carlo, P. Carman, A. Carruthers, S. Carter, I.S. Carvalho, P. Carvalho, F. Casson, D. Chalk, B. Chamberlain, P. Chauhan, A. Chow, A. Churchman, D. Ciric, M. Clark, J. Clarkson, R. Clarkson, T. Clayton, M. Cleverly, P. Coates, I. Coffey, J. Collins, S. Conroy, N.J. Conway, R. Conway, J. Cook, M. Cooke, D. Coombs, P. Cooper, S. Cooper, G. Corrigan, R. Cotterell, A. Coulson, M. Cox, S. Cox, S. Cramp, D. Craven, R. Craven, M. Crick, D. Croft, T. Cronin, Z. Cui, A. Cullen, R. Cumming, C. Cummings, A. Dal Molin, P. Dalgliesh, S. Dalley, A. Danquah, S. Davies, G. Davis, H. Dawson, K. Dawson, S. Dawson, I. Day, L. de Caires, E. de la Luna, K. Deakin, J. Deane, M. Dearing, A. Dennett, T. Dickson, J. Dobrashian, T. Dochnal, S. Dorling, D. Douai, S. Dowson, J. Drewitt, G. Drummond, P. Dumortier, R. Eade, R. Eastham, K. Eden, J. Edmond, J. Edwards, P. Edwards, H. Elamin, S. Elford, H. El-Haroun, P. Ellis, C. Elsmore, S. Emery, G. Evans, S. Evans, D. Fagan, T. Farmer, I. Farquhar, R. Felton, F. Ferner, J. Fessey, P. Finburg, G. Fishpool, L. Fittill, J. Flanagan, K. Flinders, S. Foley, M. Fontana, M. Fortune, J. Foster, C. Fowler, P. Fox, O. Franklin, R. Franklin, R. Fraser, S. French, M. Furseman, A. Gabbidon, L. Garcia, J. Garcia, M. Gardener, D. Gear, T. Gedling, S. Gee, P. Gell, R. George, S. Gerasimov, M. Gethins, Z. Ghani, L. Giacomelli, C. Gibson, V. Gilsenan, C. Giroud, R. Glen, J. Goff, C. Goodman, A. Goodyear, A. Gordon, S. Gore, S. Gosden, N. Gotts, E. Gow, W. Graham, G. Graham, M. Green, R. Gregory, R. Griffiths, T. Griffiths, F. Griph, C. Grundy, T. Grundy, D. Guard, D. Guest, C. Gurl, S. Hacquin, A. Hakola, K. Hammond, H. Harmer, P. Harper, S. Harris, D. Hart, D. Hattan, A. Haupt, J. Hawes, N. Hawkes, J. Hawkins, P. Hawkins, S. Hayes, S. Hazael, D. Heads, P. Heesterman, O. Hemming, R.B. Henriques, G. Hermon, G. Hewson, T. Hibberd, M. Hill, J. Hillesheim, I. Hirb, K. Ho, C. Hogben, A. Hollingsworth, S. Hollis, M. Hook, D. Hopley, N. Horsten, A. Horton, L.D. Horton, L. Horvath, S. Hotchin, Z. Huang, E. Hubenov, V. Huber, A. Huber, C. Huddart, T. Huddleston, T. Hunter, Y. Husain, A. Hynes, J. Ingleby, S. Ives, E. Ivings, S. Jackson, T. Jackson, P. Jacquet, N. Jayasekera, I. Jepu, D. Jezzard, E. Joffrin, R. Johnson, J. Johnston, C. Jones, E. Jones, G. Jones, L. Jones, S. Jones, T. Jones, M. Jones, A. Joyce, M. Juvonen, A. Kantor, A. Kappatou, G. Karajgikar, J. Karhunen, I. Karnowska-Paterski, E. Karsakos, G. Kaveney, G. Kay, D. Keeling, T. Keenan, R. Kelly, W. Kelly, D. Kennedy, R. Kennedy, O. Kent, K. Khan, D. King, D. Kinna, V. Kiptily, K. Kirov, G. Kneale, M. Knight, P. Knight, J. Knipe, R. Knipe, S. Knipe, P. Kochanski, D. Kos, M. Kovari, E. Kowalska-Strzęciwilk, N. Kraus, M. Kresina, B. Labit, A. Laing, V. Laksharam, N. Lam, B. Lane, C. Lane, T. Lavender, A. Lawson, K. Lawson, G. Learoyd, T. Leeson, X. Lefebvre, J. Lehmann, M. Lennholm, K. Lennon, E. Lerche, S. Lesnoj, E. Letellier, L. Lewin, J. Lewis, J. Li, G. Liddiard, E. Litherland-Smith, F. Liu, R. Lobel, J. Logan, P. Lomas, C. Long, U. Losada, C. Loveridge, T. Lowe, C. Lowry, R. Lucock, G. Lyons, J. Macdonald, P. Macheta, T. Madden, J. Maddock, C.F. Maggi, J. Mailloux, A. Manning, C. Manning, N. Mantel, A. Manzanares, S. Marsden, J. Marsh, R. Marshall, A. Martin, M. Maslov, G. Matthews, N. Mayfield, M. Mayoral, R. McAdams, L. McCafferty, P. McCullen, D. McDonald, A. McDonnell, D. McGuckin, T. McIver, V. McKay, R. McKean, L. McNamee, A. McShee, R. Meadows, D. Mederick, M. Medland, K. Meghani, A. Meigs, S. Menmuir, I. Merrigan, S. Mianowski, P. Middleton, C. Miles, J. Milnes, A. Milocco, J. Mitchell, P. Mitchell, P. Monaghan, I. Monakhov, P. Moody, R. Mooney, C. Moore, N. Mooring, L. Morgan, R. Morgan, J. Morris, O. Morton, S. Morton, P. Mulvana, S. Munot, R. Munro-Smith, K. Musgrave, R. Naish, N. Neethiraj, J. Neilson, A. Newman, S. Ng, M. Nicassio, K. Nicholls, M. Nightingale, C. Noble, R. Normington, C. Nygaard, J. O’Callaghan, R. Olney, B. O’Meara, M. O’Mullane, C. O’Neill, C. Opara, K. O’Rourke, J. Ottley, K. Otu, A. Owen, N. Pace, K. Palamartchouk, D. Paley, J. Palgrave, G. Papadopoulos, V. Parail, A. Parrott, A. Parsloe, L. Parsons, R. Parsons, A. Patel, J. Patel, A. Peacock, M. Pearce, T. Pearce, I. Pearson, J. Penzo, A. Perdas, T. Pereira, C. Perez Von Thun, D. Perry, N. Petrella, M. Peyman, N. Platt, M. Poradzinski, M. Porter, M. Porton, C. Powell, J. Pozzi, M. Price, L. Price, P. Puglia, D. Pulley, K. Purahoo, M. Rainford, A. Raj, S. Randhawa, S. Rapa, K. Ravisankar, C. Rayner, A. Read, C. Reux, S. Reynolds, V. Riccardo, L. Richiusa, D. Rigamonti, F. Rimini, J. Roberts, R. Robins, S. Robinson, T. Robinson, D. Robson, S. Romanelli, F. Rose, C. Rose-Innes, D. Rouse, S. Rowe, N. Rowland, D. Rowlands, M. Rubel, K. Sabin, R. Salmon, H. Salter, A. Sanders, E. Sanders, I. Sanders, D. Sandiford, F. Sanni, R. Sarwar, R. Sayles, C. Scaysbrook, G. Scott, D. Scraggs, S. Scully, R. Sealey, E. Searle, M. Segato, M. Sertoli, C. Shanks, R. Sharma, A. Shaw, K. Sheahan, H. Sheikh, D. Shrestha, R. Siddiqui, S. Silburn, J. Silva, D. Simfukwe, J. Simpson, M. Sinclair, A. Sips, P. Sirén, S. Skeats, N. Skinner, B. Slade, J. Slater, T. Smart, G. Smith, J. Smith, N. Smith, P. Smith, T. Smith, F. P. Smith, J. Snell, K. Snelling, K. Soare, E. Solano, A. Spelzini, C. Srinivasan, Z. Stancar, P.A. Staniec, M. Stead, R. Steadman, L. Steel, D. Steele, A. Stephen, J. Stephens, L. Stevenson, P. Stevenson, C. Steventon, L. Sticklen, M. Stojanov, S. Strikwerda, C. Stuart, G. Stubbs, N. Studd, W. Studholme, H. Sun, S. Surendran, G. Szepesi, M. Szoke, H. Tan, A. Taylor, D. Taylor, K. Taylor, A. Thingore, B. Thomas, J. Thomas, A. Thorman, A. Tilley, A. Tipton, N. Tipton, H. Todd, P. Tonner, A. Tookey, M. Towndrow, M. Tsang, E. Tsitrone, I. Turner, M. Turner, G. Tvalashvili, S. Tyrrell, A. Vadgama, D. Valcarcel, Q. Van Der Westhuizen, J. Verdon, N. Vianello, A. Vittal, Z. Vizvary, B. Wakeling, M. Walker, R. Walker, T. Wall, M. Walsh, T. Walsh, J. Walters, J. Walton, R. Walton, S. Warder, F. Warren, R. Warren, J. Waterhouse, T. Webster, G. Wells, C. Wellstood, A. West, M. Wheatley, S. Whiffin, A. Whitehead, C. Whitehead, D. Whittaker, A. Widdowson, J. Wilcox, D. Wilkins, R. Wilkins, J. Williams, M. Williams, D. Willoughby, A. Wilson, I. Wilson, T. Wilson, M. Wischmeier, P. Wise, G. Withenshaw, A. Withycombe, D. Witts, J. Witts, R. Wood, L. Woodham, C. Woodley, J. Woodley, R. Woodley, B. Woods, S. Wray, T. Xu, I. Young, R. Young, K-D. Zastrow, Y. Zayachuk, and M. Zerbini
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JET ,tritium ,operations ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
JET, the world’s largest operating tokamak with unique Be/W wall and tritium handling capability, completed a Deuterium-Tritium (D-T) campaign in 2021 (Maggi et al 29th Fusion Energy Conf. ) following a decade of preparatory experiments, dedicated enhancements, technical rehearsals and training (Horton et al 2016 Fusion Eng. Des. 109–111 925). Operation with tritium raises significant technical, safety and scientific challenges not encountered in standard protium or deuterium operation. This contribution describes the tritium operational requirements, pulses and technical preparations, new operating procedures, lessons learned and details on the achieved operational availability and performance. The preparation and execution of the recent JET tritium experiments benefitted from the previous experience in 1991 (Preliminary Tritium Experiment), 1997 (DTE1 campaign) and 2003 (Trace Tritium Campaigns) and consisted of the following five phases: technical rehearsals and scenario preparation, tritium commissioning, 100% tritium campaign, D-T campaign (DTE2), tritium clean-up. Following the clean-up JET resumed normal operation and is currently undertaking a further D-T campaign (DTE3).
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- 2024
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46. Towards truly sustainable IoT systems: the SUPERIOT project
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Marcos Katz, Tuomas Paso, Konstantin Mikhaylov, Luis Pessoa, Helder Fontes, Liisa Hakola, Jaakko Leppäniemi, Emanuel Carlos, Guido Dolmans, Julio Rufo, Marcin Drzewiecki, Hazem Sallouha, Bruce Napier, André Branquinho, and Kerstin Eder
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sustainable wireless communications systems ,hybrid optical-radio communications ,localization ,energy transfer ,printed electronics technologies ,energy modeling and analysis ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
This paper provides an overview of the SUPERIOT project, an EU SNS JU (Smart Networks and Services Joint Undertaking) initiative focused on developing truly sustainable IoT systems. The SUPERIOT concept is based on a unique holistic approach to sustainability, proactively developing sustainable solutions considering the design, implementation, usage and disposal/reuse stages. The concept exploits radio and optical technologies to provide dual-mode wireless connectivity and dual-mode energy harvesting as well as dual-mode IoT node positioning. The implementation of the IoT nodes or devices will maximize the use of sustainable printed electronics technologies, including printed components, conductive inks and substrates. The paper describes the SUPERIOT concept, covering the key technical approaches to be used, promising scenarios and applications, project goals and demonstrators which will be developed to the proof-of-concept stage. In addition, the paper briefly discusses some important visions on how this technology may be further developed in the future.
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- 2024
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47. Hospital physicians´ working hour characteristics and sleep quality: a cross-sectional analysis of realized working hour and survey data
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Kati Karhula, Aki Koskinen, Jenni Ervasti, Tarja Hakola, Veli-Matti Isoviita, Ilkka Kivimäki, Sampsa Puttonen, Tuula Oksanen, and Mikko Härmä
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On-call work ,Payroll data ,Working time ,Sleep quality ,Sleep difficulties ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Hospital physicians’ work includes on-call duties to provide 24/7 health care. Previous studies using self-reported survey data have associated long working hours and on-call work with sleep difficulties. To reduce recall bias, we complemented survey data with payroll-based objective data to study whether hospital physicians’ realized working hours are associated with sleep. Methods The study was nested within the Finnish Public Sector study. We used survey data on 728 hospital physicians (mean age 43.4 years, 62% females) from 2015 linked to realized daily working hour data from 3 months preceding the survey. The associations of working hour characteristics with sleep quantity and quality were studied with multinomial logistic regression analysis adjusted for demographics, overall stressfulness of life situation, control over scheduling of shifts, and hospital district. Results One fourth (26%) of the participants reported short (≤6.5 h) average sleep duration. Frequent night work (> 6 shifts/91 days) was associated with short sleep (OR 1.87 95%CI 1.23–2.83) compared to no night work. Approximately one third (32%) of the physicians reported insufficient sleep. Physicians with long weekly working hours (> 48 hours) had higher odds for insufficient sleep (OR 1.78 95%CI 1.15–2.76) than physicians with short weekly working hours ( 12 shifts/3 months OR 2.00 95%CI 1.08–3.72), frequent night work (OR 1.60 95%CI 1.09–2.37), and frequent short shift intervals (≤11 hours; > 12 times/3 months OR 1.65 95%CI 1.01–2.69) compared to not having these working hour characteristics. Nearly half of the physicians (48%) reported at least one sleep difficulty at least two times a week and frequent night work increased odds for difficulties in initiating sleep (OR 2.43 95%CI 1.04–5.69). Otherwise sleep difficulties were not associated with the studied working hour characteristics. Conclusion We used realized working hour data to strengthen the evidence on on-call work and sleep quality and our results advice to limit the frequency of night work, on-call shifts, short shift intervals and long weekly working hours to promote hospital physicians’ sufficient sleep.
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- 2022
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48. Influence of surface morphology on erosion of plasma-facing components in H-mode plasmas of ASDEX Upgrade
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Lahtinen, A., Hakola, A., Likonen, J., Balden, M., Krieger, K., Gouasmia, S., Bogdanovic Radovic, I., Provatas, G., Kelemen, M., Markelj, S., Pedroni, M., Uccello, A., Vassallo, E., Dellasega, D., and Passoni, M.
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- 2022
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49. Emissions of volatile organic compounds from Norway spruce and potential atmospheric impacts
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Hannele Hakola, Ditte Taipale, Arnaud Praplan, Simon Schallhart, Steven Thomas, Toni Tykkä, Aku Helin, Jaana Bäck, and Heidi Hellén
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biogenic volatile organic compound emissions ,monoterpene ,sesquiterpene ,isoprene ,Norway spruce emissions ,SOA formation ,Forestry ,SD1-669.5 ,Environmental sciences ,GE1-350 - Abstract
Published biogenic volatile organic compound (BVOC) emission rates of Norway spruces vary a lot. In this study we combined published Norway spruce emission rates measured in boreal forests and added our new, unpublished emission data from Southern (SF) and Northern Finland (NF). Standardized summer monthly mean emission potentials of isoprene vary from below the detection limit to 7 μg g–1(dw) h–1, and monoterpene (MT) and sesquiterpene (SQT) emission potentials 0.01–3 μg g–1(dw) h–1 and 0.03–2.7 μg g–1(dw) h–1, respectively. In this study, we found much higher SQT emissions from Norway spruces than previously measured, and on average SQTs had higher emission potentials than isoprene or MTs. The highest monthly mean SQT emission potential of 13.6 μg g–1(dw) h–1 was observed in September in Southern Finland. We found that none of the younger (33–40 years) trees in Hyytiälä, Southern Finland, emitted isoprene, while one 50-year-old tree was a strong isoprene emitter. The difference due to age could not be confirmed, since all measured small trees were growing in Hyytiälä, so this could also be due to the same genetic origin. On average, older trees (>80 years) emitted about ten times more isoprene and MTs than younger ones (
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- 2023
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50. Overview of plasma-tungsten surfaces interactions on the divertor test sector in WEST during the C3 and C4 campaigns
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M. Diez, M. Balden, S. Brezinsek, Y. Corre, N. Fedorczak, M. Firdaouss, E. Fortuna, J. Gaspar, J.P. Gunn, A. Hakola, T. Loarer, C. Martin, M. Mayer, P. Reilhac, M. Richou, E. Tsitrone, and T. Vuoriheimo
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WEST ,Tungsten ,Erosion and deposition ,Plasma-wall interactions ,Monoblocks ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Studying the ageing of tungsten monoblocks, their erosion and their fuel inventory is the priority of the WEST post-mortem analyses programme. Actively-cooled ITER-like plasma-facing units (PFUs) and special W-coated marker lower divertor tiles were retrieved from the WEST divertor after the C3 and C4 experimental campaigns to perform ex-situ analyses. The erosion/deposition pattern on the divertor was determined. The deposition is found mainly on the inner side which is covered by layered deposits that increase in thickness in the radial direction from a few hundreds of nm to a maximum of >10 µm. The deposits are mainly composed of W, O, C, B and D coming from transport of W in the vacuum chamber, oxidized layers and boronizations. Traces of Cu, Fe, Mo, Cr, Ag were also detected. A maximum deposition rate of about 1.4 nm/s was estimated while a minimum campaign-averaged net erosion rate of 0.1 nm/s was measured for the erosion markers at the strike line areas. No assessment of the erosion could be done for the W monoblocks due to a lack of diagnostics. However, the W monoblock edges clearly show traces of damage (melting, cracks) when exposed to the parallel heat flux due to relative misalignment of ITER-like PFUs during assembly. Optical hot spots were also evidenced, confirming the numerical simulations, although their impact on the operation and the lifetime of the components was limited.
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- 2023
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