| 1. |
|
|
| 2. |
- Joffrin, E., et al.
(författare)
-
Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
- 2019
-
Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
-
Forskningsöversikt (refereegranskat)abstract
- For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D-T campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the D-T preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling, and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, high confinement mode (H-mode) access, Be and W erosion, fuel recovery, etc). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and a mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating schemes (such as the three-ions scheme), new diagnostics (neutron camera and spectrometer, active Alfven eigenmode antennas, neutral gauges, radiation hard imaging systems...) and the calibration of the JET neutron diagnostics at 14 MeV for accurate fusion power measurement. The active preparation of JET for the 2020 D-T campaign provides an incomparable source of information and a basis for the future D-T operation of ITER, and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.
|
|
| 3. |
- Murari, A., et al.
(författare)
-
A control oriented strategy of disruption prediction to avoid the configuration collapse of tokamak reactors
- 2024
-
Ingår i: Nature Communications. - 2041-1723 .- 2041-1723. ; 15:1
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of thermonuclear fusion consists of producing electricity from the coalescence of light nuclei in high temperature plasmas. The most promising route to fusion envisages the confinement of such plasmas with magnetic fields, whose most studied configuration is the tokamak. Disruptions are catastrophic collapses affecting all tokamak devices and one of the main potential showstoppers on the route to a commercial reactor. In this work we report how, deploying innovative analysis methods on thousands of JET experiments covering the isotopic compositions from hydrogen to full tritium and including the major D-T campaign, the nature of the various forms of collapse is investigated in all phases of the discharges. An original approach to proximity detection has been developed, which allows determining both the probability of and the time interval remaining before an incoming disruption, with adaptive, from scratch, real time compatible techniques. The results indicate that physics based prediction and control tools can be developed, to deploy realistic strategies of disruption avoidance and prevention, meeting the requirements of the next generation of devices.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Meyer, E., et al.
(författare)
-
The state of the art in beyond 5G distributed massive multiple-input multiple-output communication system solutions
- 2022
-
Ingår i: Open Research Europe. - : F1000 Research Ltd. - 2732-5121. ; 2
-
Forskningsöversikt (refereegranskat)abstract
- Beyond fifth generation (5G) communication systems aim towards data rates in the tera bits per second range, with improved and flexible coverage options, introducing many new technological challenges in the fields of network architecture, signal pro- cessing, and radio frequency front-ends. One option is to move towards cell-free, or distributed massive Multiple-Input Multiple-Output (MIMO) network architectures and highly integrated front-end solutions. This paper presents an outlook on be- yond 5G distributed massive MIMO communication systems, the signal processing, characterisation and simulation challenges, and an overview of the state of the art in millimetre wave antennas and electronics.
|
|
| 7. |
- Carlsson, Emelie, et al.
(författare)
-
A real-estate price index for Stockholm, 1726–1875
- 2022
-
Ingår i: Banking, Bonds, National Wealth, and Stockholm House Prices, 1420–2020. - Stockholm : Ekerlids förlag. - 9789189323605 ; , s. 297-334
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter presents new, nominal and real price indices for real estate in Stockholm from 1726 up to 1875. The new series presented here can be linked to already existing price indices for real estate in Stockholm: from 1875 up to 1957; from 1957 to1975 3 and; from 1975 up to 2020.For this, a new database is used that covers registered real estate transactions in the present inner city of Stockholm for the period and the method of repeated sales is applied. The indices are based on information from 22,169 unique transactions. To control for qualitative changes inthe housing stock, a database of 7,915 issued building permits has been used.
|
|
| 8. |
- Enjin, Anders, et al.
(författare)
-
Developmental disruption of recurrent inhibitory feedback results in compensatory adaptation in the Renshaw cell-motor neuron circuit
- 2017
-
Ingår i: Journal of Neuroscience. - 0270-6474 .- 1529-2401. ; 37:23, s. 5634-5647
-
Tidskriftsartikel (refereegranskat)abstract
- When activating muscles, motor neurons in the spinal cord also activate Renshaw cells, which provide recurrent inhibitory feedback to the motor neurons. The tight coupling with motor neurons suggests that Renshaw cells have an integral role in movement, a role that is yet to be elucidated. Here we used the selective expression of the nicotinic cholinergic receptor α2 (Chrna2) in mice to genetically target the vesicular inhibitory amino acid transporter (VIAAT) in Renshaw cells. Loss of VIAAT from Chrna2Cre-expressing Renshaw cells did not impact any aspect of drug-induced fictive locomotion in the neonatal mouse or change gait, motor coordination, or grip strength in adult mice of both sexes. However, motor neurons from neonatal mice lacking VIAAT in Renshaw cells received spontaneous inhibitory synaptic input with a reduced frequency, showed lower input resistance, and had an increased number of proprioceptive glutamatergic and calbindin-labeled putative Renshaw cell synapses on their soma and proximal dendrites. Concomitantly, Renshaw cells developed with increased excitability and a normal number of cholinergic motor neuron synapses, indicating a compensatory mechanism within the recurrent inhibitory feedback circuit. Our data suggest an integral role for Renshaw cell signaling in shaping the excitability and synaptic input to motor neurons.
|
|
| 9. |
- Eriksson, Klas A. M., 1983-
(författare)
-
How the City was Owned : Property Markets, Property Rights, and Entrepreneurship in Stockholm, Sweden 1726-2018
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this dissertation three central themes concerning the ownership and allocation in the city of Stockholm over long periods are examined.The first theme property markets involves constructions of real estate price indexes spanning from 1726 to 2018. The second theme property rights concerns the regulation of private and public ownership of real estate from 1874 to 2010. The third theme entrepreneurship in urban environments is an examination of the efforts to influence property markets and property rights through entrepreneurship in difference sectors from the 1920s to the 2010s.With an extensive amount of empirical material, this dissertation examines and relates the three themes to each other and shed new light on urban dynamics from an historical perspective. This dissertation is particularly important today when ownership and prices of real estate in cities are burning issues, and entrepreneurship is of central importance for development. The dissertation is a compilation thesis consisting of six articles.
|
|
| 10. |
- Eriksson, Klas, 1983, et al.
(författare)
-
Design and Characterization of H-Band (220-325 GHz) Amplifiers in a 250-nm InP DHBT Technology
- 2014
-
Ingår i: IEEE Transactions on Terahertz Science and Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 2156-342X .- 2156-3446. ; 4:1, s. 56-64
-
Tidskriftsartikel (refereegranskat)abstract
- Design and characterization of InP DHBT amplifiers in common-emitter and common-base topologies are presented. Both one-stage and multistage circuits are demonstrated. For one of the amplifiers, a peak gain of 24 dB at 255 GHz is measured, which is among the highest reported gains for HBT amplifiers above 200 GHz, and more than 10 dB gain at 210-315 GHz. The noise figure of this amplifier is measured on-wafer at 240-295 GHz, and it demonstrates a minimum noise figure of 10.4 dB at 265 GHz, which is the lowest reported noise figure for HBT amplifiers above 200 GHz.
|
|
