| 1. |
- Bulten, W, et al.
(författare)
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Artificial intelligence for diagnosis and Gleason grading of prostate cancer: the PANDA challenge
- 2022
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Ingår i: Nature medicine. - : Springer Science and Business Media LLC. - 1546-170X .- 1078-8956. ; 28:21, s. 154-
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Tidskriftsartikel (refereegranskat)abstract
- Artificial intelligence (AI) has shown promise for diagnosing prostate cancer in biopsies. However, results have been limited to individual studies, lacking validation in multinational settings. Competitions have been shown to be accelerators for medical imaging innovations, but their impact is hindered by lack of reproducibility and independent validation. With this in mind, we organized the PANDA challenge—the largest histopathology competition to date, joined by 1,290 developers—to catalyze development of reproducible AI algorithms for Gleason grading using 10,616 digitized prostate biopsies. We validated that a diverse set of submitted algorithms reached pathologist-level performance on independent cross-continental cohorts, fully blinded to the algorithm developers. On United States and European external validation sets, the algorithms achieved agreements of 0.862 (quadratically weighted κ, 95% confidence interval (CI), 0.840–0.884) and 0.868 (95% CI, 0.835–0.900) with expert uropathologists. Successful generalization across different patient populations, laboratories and reference standards, achieved by a variety of algorithmic approaches, warrants evaluating AI-based Gleason grading in prospective clinical trials.
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| 2. |
- Brändström, B. U. E., et al.
(författare)
-
Results from the intercalibration of optical low-light calibration sources 2011
- 2012
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Ingår i: Geoscientific Instrumentation, Methods and Data Systems. - : European Geosciences Union (EGU). - 2193-0856 .- 2193-0864. ; 1, s. 43-51
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Tidskriftsartikel (refereegranskat)abstract
- Following the 38th Annual European Meeting on Atmospheric Studies by Optical Methods in Siuntio in Finland, an intercalibration workshop for optical low light calibration sources was held in Sodankylä, Finland. The main purpose of this workshop was to provide a comparable scale for absolute measurements of aurora and airglow. All sources brought to the intercalibration workshop were compared to the Fritz Peak reference source using the Lindau Calibration Photometer built by Wilhelm Barke and Hans Lauche in 1984. The results were compared to several earlier intercalibration workshops. It was found that most sources were fairly stable over time, with errors in the range of 5–25%. To further validate the results, two sources were also intercalibrated at UNIS, Longyearbyen, Svalbard. Preliminary analysis indicates agreement with the intercalibration in Sodankylä within about 15–25%.
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| 3. |
- Chen, Hao, 1988, et al.
(författare)
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Comparative Study and Design Optimization of a Dual-Mechanical-Port Electric Machine for Hybrid Electric Vehicle Applications
- 2022
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Ingår i: IEEE Transactions on Vehicular Technology. - 0018-9545 .- 1939-9359. ; 71:8, s. 8341-8353
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Tidskriftsartikel (refereegranskat)abstract
- A new dual-mechanical-port (DMP) electric machine for hybrid electric vehicle applications, particularly in the power-split continuously variable transmission systems, is proposed in this paper. In order to comprehensively and quantitatively evaluate the pros and cons of the proposed machine, a comparative study of four DMP electric machines with different topologies is conducted. These four investigated DMP electric machines include a conventional DMP machine, a DMP machine with spoke-type permanent magnets, a DMP machine with reluctance rotor, and a DMP machine with open slots which is the proposed machine in this paper. Even though these four machines have similar topologies, they have different operating principles, which are demonstrated in detail. The comparison results indicate that the DMP machine with open slots outperforms the others in terms of torque/power density, efficiency, magnet utilization, etc. Accordingly, the DMP machine with open slots is selected for further investigation and optimization. A large-scale multi-objective optimization is carried out for this machine, where the differential evolution algorithm serves as a global search engine to target optimal performance. Finally, an optimal design is prototyped, and the experimental results are performed to verify the effectiveness of the analysis and simulation results in this paper.
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| 4. |
- Chen, Hao, 1988, et al.
(författare)
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Design and Analysis of a Variable-Speed Constant-Amplitude Wind Generator for Stand-Alone DC Power Applications
- 2023
-
Ingår i: IEEE Transactions on Industrial Electronics. - 0278-0046 .- 1557-9948. ; 70:8, s. 7731-7742
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Tidskriftsartikel (refereegranskat)abstract
- This article presents the design and analysis of a permanent magnet (PM) wind generator, which consists of two sets of windings, and two rotors. The proposed PM wind generator is designed for variable-speed constant-amplitude voltage operation in dc power applications, in order to maximize the utilization of wind energy and make the electricity more accessible to stand-alone situations, e.g., remote areas and offshore islands. The operating principle of the variable-speed constant-amplitude voltage operation of the proposed PM wind generator is demonstrated in detail. A comparative study is carried out among the proposed generator, a conventional surface-mounted PM synchronous generator, and an existing counterpart generator used for the same application. The results show that compared to the conventional PM synchronous generator and the existing counterpart, the proposed PM wind generator exhibits the advantages of high induced voltage, high torque/power density, high efficiency, etc. Finally, the proposed PM wind generator is prototyped and manufactured. The validity of the variable-speed constant-amplitude operation of the proposed generator under both steady-state and dynamic conditions, is verified by experimental results.
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| 5. |
- Cai, D. Q., et al.
(författare)
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A study of control chart for adjusted processes
- 1999
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Ingår i: The 26th International Conference on Computers & Industrial Engineering (the 26th C & IE) : December 15-17, 1999, Melbourne, Australia. ; , s. 443-447, s. 443-447
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Konferensbidrag (refereegranskat)
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| 6. |
- Yan, Yuming, et al.
(författare)
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Hybrid-Magnet Variable Flux Memory Machine With Improved Field Regulation Capability for Electric Vehicle Applications
- 2023
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Ingår i: IEEE Transactions on Transportation Electrification. - 2332-7782. ; 9:1, s. 586-597
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Tidskriftsartikel (refereegranskat)abstract
- This article aims to investigate a novel hybrid-magnet variable flux memory machine (VFMM) with improved field regulation capability for electric vehicle applications. Two sets of permanent magnets (PMs), i.e., high-energy-density neodymium-iron-boron PM and low coercive force (LCF) PM, are arranged in a delta array to improve field regulation capability and torque density. The machine topology, key features, and operating principle of the presented machine are demonstrated. Based on the simplified magnetic circuit model, the underlying design tradeoffs of the presented machine are revealed qualitatively. The nonlinear magnetic circuit model of the presented machine taking saturation and hybrid-magnet leakage flux into consideration is built for machine analysis. Electromagnetic performance comparisons are carried out by finite element analysis between the presented VFMM and the existing VFMM. The results show that the presented machine can achieve significantly improved flux regulation capability while maintaining the high output torque due to the improved arrangement of hybrid magnetic branches and enhanced flux concentration effect. Finally, the investigated VFMM is prototyped. The operating principle and predicted results are verified by experimental results.
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| 7. |
- Cao, H. W., et al.
(författare)
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First-principles study on electronic and magnetic properties of (Mn,Fe)-codoped ZnO
- 2014
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Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853. ; 352:1, s. 66-71
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Tidskriftsartikel (refereegranskat)abstract
- First-principle calculations have been performed to investigate the electronic and magnetic properties of (Mn,Fe)-codoped ZnO within the generalized gradient approximation (GGA) and GGA+U schemes. The formation energy of five different configurations is investigated and the ground state is demonstrated to be ferromagnetic ordering. By applying the U correction, the band gap energy of pure ZnO is close to the experimental values, while the ferromagnetic ordering of the ground state remains unchanged. The ferromagnetic stabilization is mediated by double exchange mechanism. In addition, defects corresponding to Zn-vacancy and O-vacancy cannot enhance the ferromagnetism obviously. These results indicate that (Mn,Fe)-codoped ZnO are promising magneto-electronic and spintronic materials. (C) 2013 Elsevier B.V. All rights reserved
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| 8. |
- Cao, H. W., et al.
(författare)
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Magnetic properties in (Mn,Fe)-codoped ZnO nanowire
- 2013
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090. ; 548, s. 480-484
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Tidskriftsartikel (refereegranskat)abstract
- Using the first-principles density functional theory, we have studied the electronic structures and magnetic properties of Mn/Fe codoped ZnO nanowires systematically. The calculated results of formation energy indicate that the configuration of the lowest energy where Mn and Fe atoms form nearest neighbors on the outer cylindrical surface layer along the [0001] direction, will be determined. The magnetic coupling of 8 types of Mn/Fe codoped ZnO nanowires was investigated and ferromagnetic state was found in certain configurations. The mechanism is from the fierce hybridization between 3d of Mn and Fe with O 2p near the Fermi level. The relative energy difference for configuration VIII is 0.221 eV, which indicates that room temperature ferromagnetism could be obtained in such a system and Mn/Fe codoped ZnO nanowires are a promising nanoscale spintronic material. (C) 2013 Elsevier B. V. All rights reserved.
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| 9. |
- Chen, Hao, 1988, et al.
(författare)
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A Permanent Magnet Brushless Doubly-Fed Electric Machine for Variable-Speed Constant-Frequency Wind Turbines
- 2023
-
Ingår i: IEEE Transactions on Industrial Electronics. - 0278-0046 .- 1557-9948. ; 70:7, s. 6663-6674
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Tidskriftsartikel (refereegranskat)abstract
- A permanent magnet brushless doubly-fed electric machine is presented in this paper. This machine is developed for variable-speed constant-frequency wind energy generation applications. Differing from conventional doubly-fed electric machines based on induction machines, a permanent magnet rotor provides the magnetic field excitations for both the control winding and the power winding in the presented machine. The operating principle of the presented machine for the variable-speed constant-frequency operation is revealed in detail. Compared to a counterpart machine, the presented machine exhibits significantly improved back- electromotive force, torque/power density, torque per magnet volume, efficiency, etc. Finally, a proof-of-concept prototype of the presented machine is fabricated, and the corresponding experimental results are provided to verify the fact that the presented machine is capable of achieving the variable-speed constant-frequency function.
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| 10. |
- Kittelmann, T., et al.
(författare)
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Using Backscattering to Enhance Efficiency in Neutron Detectors
- 2017
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Ingår i: IEEE Transactions on Nuclear Science. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9499 .- 1558-1578. ; 64:6, s. 1562-1573
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Tidskriftsartikel (refereegranskat)abstract
- The principle of using strongly scattering materials to recover efficiency in detectors for neutron instruments, via backscattering of unconverted thermal neutrons, is discussed in general. The feasibility of the method is illustrated through Geant4-based simulations involving thermal neutrons impinging on a specific setup with a layer of polyethylene placed behind a single-layered boron-10 thin-film gaseous detector. The results show that detection efficiencies can be as much as doubled in the most ideal scenario, but with associated adverse contributions to spatial and timing resolutions of, respectively, centimeters and tens of microseconds. Potential mitigation techniques to contain the impact on resolution are investigated and are found to alleviate the issues to some degree, at a cost of reduced gain in efficiency.
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