Search results for "Limiter"
showing 5 items of 25 documents
Optimization of the first wall for the DEMO water cooled lithium lead blanket
2015
The maximum heat load capacity of a DEMO First Wall (FW) of reasonable cost may impact the decision of the implementation of limiters in DEMO. An estimate of the engineering limit of the FW heat load capacity is an essential input for this decision. This paper describes the work performed to optimize the FW of the Water Cooled Lithium-Lead (WCLL) blanket concept for DEMO fusion reactor in order to increase its maximum heat load capacity. The optimization is based on the use of water at typical Pressurised Water Reactors conditions as coolant. The present WCLL FW with a waved plasma-faced surface and with circular channels was studied and the heat load limit has been predicted with FEM analy…
FAST EDGE-FILTERED IMAGE UPSAMPLING.
2011
We present a novel edge preserved interpolation scheme for fast upsampling of natural images. The proposed piecewise hyperbolic operator uses a slope-limiter function that conveniently lends itself to higher-order approximations and is responsible for restricting spatial oscillations arising due to the edges and sharp details in the image. As a consequence the upsampled image not only exhibits enhanced edges, and discontinuities across boundaries, but also preserves smoothly varying features in images. Experimental results show an improvement in the PSNR compared to typical cubic, and spline-based interpolation approaches.
Web crawling dla celów lingwistycznych. Wybrane aspekty gromadzenia i analizy danych tekstowych na przykładzie rosyjskojęzycznych newsów internetowych
2021
Autor niniejszego artykułu zgromadził ok. 2,7 mln rosyjskojęzycznych newsów internetowych. Zasadnicze cele tego tekstu stanowią: omówienie pojęcia web crawlingu w odniesieniu do pozyskiwania internetowych danych tekstowych, omówienie kwestii strukturyzacji takich danych w nieanotowanych korpusach tekstowych, a także przedstawienie wybranych aspektów analizy danych strukturyzowanych w ten sposób. Autor rozpatruje newsy internetowe jako połączenie tekstu zasadniczego oraz identyfikujących i charakteryzujących go metadanych (wyróżnionych podczas automatycznej ich ekscerpcji ze stron internetowych). Rozdział newsów na tekst zasadniczy i metadane stwarza możliwość przeprowadzenia ich analizy z d…
Performance Improvement of Grid-Integrated Doubly Fed Induction Generator under Asymmetrical and Symmetrical Faults
2023
The doubly fed induction generator (DFIG)-based wind energy conversion system (WECS) suffers from voltage and frequency fluctuations due to the stochastic nature of wind speed as well as nonlinear loads. Moreover, the high penetration of wind energy into the power grid is a challenge for its smooth operation. Hence, symmetrical faults are most intense, inflicting the stator winding to low voltage, disturbing the low-voltage ride-through (LVRT) functionality of a DFIG. The vector control strategy with proportional–integral (PI) controllers was used to control rotor-side converter (RSC) and grid-side converter (GSC) parameters. During a symmetrical fault, however, a series grid-side converter…
Optical limiters relying on VO2 phase transition in thin multilayer films
2022
We propose a self-activating optical limiter device based on phase transition of vanadium dioxide in thin multilayer films. The optimal geometry reduces the transmitted power by ~ 70% and shows a recovery time of 10 ns.