| 1. |
-
Overview of the JET results
- 2015
-
Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 55:10
-
Tidskriftsartikel (refereegranskat)
|
|
| 2. |
- Fenstermacher, M.E., et al.
(författare)
-
DIII-D research advancing the physics basis for optimizing the tokamak approach to fusion energy
- 2022
-
Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 62:4
-
Tidskriftsartikel (refereegranskat)abstract
- DIII-D physics research addresses critical challenges for the operation of ITER and the next generation of fusion energy devices. This is done through a focus on innovations to provide solutions for high performance long pulse operation, coupled with fundamental plasma physics understanding and model validation, to drive scenario development by integrating high performance core and boundary plasmas. Substantial increases in off-axis current drive efficiency from an innovative top launch system for EC power, and in pressure broadening for Alfven eigenmode control from a co-/counter-I p steerable off-axis neutral beam, all improve the prospects for optimization of future long pulse/steady state high performance tokamak operation. Fundamental studies into the modes that drive the evolution of the pedestal pressure profile and electron vs ion heat flux validate predictive models of pedestal recovery after ELMs. Understanding the physics mechanisms of ELM control and density pumpout by 3D magnetic perturbation fields leads to confident predictions for ITER and future devices. Validated modeling of high-Z shattered pellet injection for disruption mitigation, runaway electron dissipation, and techniques for disruption prediction and avoidance including machine learning, give confidence in handling disruptivity for future devices. For the non-nuclear phase of ITER, two actuators are identified to lower the L-H threshold power in hydrogen plasmas. With this physics understanding and suite of capabilities, a high poloidal beta optimized-core scenario with an internal transport barrier that projects nearly to Q = 10 in ITER at ∼8 MA was coupled to a detached divertor, and a near super H-mode optimized-pedestal scenario with co-I p beam injection was coupled to a radiative divertor. The hybrid core scenario was achieved directly, without the need for anomalous current diffusion, using off-axis current drive actuators. Also, a controller to assess proximity to stability limits and regulate β N in the ITER baseline scenario, based on plasma response to probing 3D fields, was demonstrated. Finally, innovative tokamak operation using a negative triangularity shape showed many attractive features for future pilot plant operation.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Menkveld, Albert J., et al.
(författare)
-
Nonstandard Errors
- 2024
-
Ingår i: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
-
Tidskriftsartikel (refereegranskat)abstract
- In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
|
|
| 7. |
- Tjora, E., et al.
(författare)
-
Patient reported exposure to smoking and alcohol abuse are associated with pain and other complications in patients with chronic pancreatitis
- 2020
-
Ingår i: Pancreatology. - : Elsevier BV. - 1424-3903. ; 20:5, s. 844-851
-
Tidskriftsartikel (refereegranskat)abstract
- Background/objectives: Smoking and alcohol abuse are established risk factors for chronic pancreatitis (CP). Few studies have examined how exposure to smoking and alcohol abuse act as risk factors for complications in CP. Our aim was to examine associations between patient reported exposure to smoking and alcohol abuse and complications in CP in a large cohort of patients from the Scandinavian and Baltic countries. Methods: We retrieved data on demographics, CP related complications and patients' histories of exposure to smoking and alcohol abuse from the Scandinavian Baltic Pancreatic Club database. Associations were investigated by univariate and multivariate logistic regression analyses. Results are presented as odds ratios (OR) with 95% confidence intervals. Results: A complete history of smoking and alcohol exposure was available for 932 patients. In multivariate regression analyses, the presence of pain and exocrine pancreatic insufficiency were both significantly associated with history of smoking (OR 1.94 (1.40-2.68), p < 0.001 and OR 1.89 (1.36-2.62), p < 0.001, respectively) and alcohol abuse (OR 1.66 (1.21-2.26), p = 0.001 and 1.55 (1.14-2.11), p = 0.005, respectively). Smoking was associated with calcifications (OR 2.89 (2.09-3.96), p < 0.001), moderate to severe ductal changes (OR 1.42 (1.05-1.92), p = 0.02), and underweight (OR 4.73 (2.23-10.02), p < 0.001). History of alcohol abuse was associated with pseudocysts (OR 1.38 (1.00-1.90) p = 0.05) and diabetes mellitus (OR 1.44 (1.03-2.01), p = 0.03). There were significantly increased odds-ratios for several complications with increasing exposure to smoking and alcohol abuse. Conclusion: Smoking and alcohol abuse are both independently associated with development of complications in patients with CP. There seems to be a dose-dependent relationship between smoking and alcohol abuse and complications in CP. (c) 2020 IAP and EPC. Published by Elsevier B.V. All rights reserved.
|
|
| 8. |
|
|
| 9. |
- Kang, JS, et al.
(författare)
-
Risk prediction for malignant intraductal papillary mucinous neoplasm of the pancreas: logistic regression versus machine learning
- 2020
-
Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1, s. 20140-
-
Tidskriftsartikel (refereegranskat)abstract
- Most models for predicting malignant pancreatic intraductal papillary mucinous neoplasms were developed based on logistic regression (LR) analysis. Our study aimed to develop risk prediction models using machine learning (ML) and LR techniques and compare their performances. This was a multinational, multi-institutional, retrospective study. Clinical variables including age, sex, main duct diameter, cyst size, mural nodule, and tumour location were factors considered for model development (MD). After the division into a MD set and a test set (2:1), the best ML and LR models were developed by training with the MD set using a tenfold cross validation. The test area under the receiver operating curves (AUCs) of the two models were calculated using an independent test set. A total of 3,708 patients were included. The stacked ensemble algorithm in the ML model and variable combinations containing all variables in the LR model were the most chosen during 200 repetitions. After 200 repetitions, the mean AUCs of the ML and LR models were comparable (0.725 vs. 0.725). The performances of the ML and LR models were comparable. The LR model was more practical than ML counterpart, because of its convenience in clinical use and simple interpretability.
|
|
| 10. |
|
|
