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841.
Marcin Morawiec 《Asian journal of control》2015,17(6):2403-2408
The paper describes the voltage control technique of induction machines supplied by a current source inverter. The control system is based on proposed new multi‐scalar variables, which are named “r.” The control system contains the output filter capacitor's model. In the sensorless control system the Z type backstepping speed observer was applied. The mathematical dependences are confirmed by simulation and experimental research. 相似文献
842.
Marcin Sydow Mariusz Pikuła Ralf Schenkel 《Journal of Intelligent Information Systems》2013,41(2):109-149
Given an entity represented by a single node q in semantic knowledge graph D, the Graphical Entity Summarisation problem (GES) consists in selecting out of D a very small surrounding graph S that constitutes a generic summary of the information concerning the entity q with given limit on size of S. This article concerns the role of diversity in this quite novel problem. It gives an overview of the diversity concept in information retrieval, and proposes how to adapt it to GES. A measure of diversity for GES, called ALC, is defined and two algorithms presented, baseline, diversity-oblivious PRECIS and diversity-aware DIVERSUM. A reported experiment shows that DIVERSUM actually achieves higher values of the ALC diversity measure than PRECIS. Next, an objective evaluation experiment demonstrates that diversity-aware algorithm is superior to the diversity-oblivious one in terms of fact selection. More precisely, DIVERSUM clearly achieves higher recall than PRECIS on ground truth reference entity summaries extracted from Wikipedia. We also report another intrinsic experiment, in which the output of diversity-aware algorithm is significantly preferred by human expert evaluators. Importantly, the user feedback clearly indicates that the notion of diversity is the key reason for the preference. In addition, the experiment is repeated twice on an anonymous sample of broad population of Internet users by means of a crowd-sourcing platform, that further confirms the results mentioned above. 相似文献
843.
The paper presents an analysis of cracking and delamination of an elastic plate bonded to a rigid substrate. The plate is subjected to a cyclic temperature loading. The bond between the plate and the substrate is simulated using rigid-frictional and rigid-cohesive-frictional interface models. The states of adaptation or incremental failure are distinguished in the case of the softening interfacial law. The proposed modelling is validated to predict fragmentation of a concrete pavement subjected to temperature loading. The obtained results can serve as reference solutions for numerical calculations of more complex cases. 相似文献
844.
845.
Mohammad Sadegh Shakeri Zaneta Swiatkowska-Warkocka Oliwia Polit Tatiana Itina Alexey Maximenko Joanna Depciuch Jacek Gurgul Marzena Mitura-Nowak Marcin Perzanowski Andrzej Dziedzic Jarosław Nęcki 《Advanced functional materials》2023,33(43):2304359
Phase formation by pulsed laser irradiation of suspended nanoparticles has recently been introduced as a promising synthesis technique for heterostructures. The main challenge still lingers regarding the exact mechanism of particle formation due to the non-equilibrium kinetic by-products resulting from the localized alternative, fast, high-temperature nature of the process. Here, the authors analyze the bond breaking/formation of copper or copper (II) interfaces with ethanol during the absorption of pulses for Cu-CuO-Cu2O formation applicable as an electrocatalyst in ethanol oxidation fuel cells. This study includes but is not limited to, a comprehensive discussion of the interaction between nano-laser pulses and suspension for practical control of the synthesis process. The observed exponential and logarithmic changes in the content of heterostructures for the CuO-ethanol and Cu-ethanol samples irradiated with different fluences are interpreted as the dominant role of physical and chemical reactions, respectively, during the pulsed laser irradiation of suspensions synthesis. It is also shown that the local interface between dissociated ethanol and the molten sphere is responsible for the oxidative/reductive interactions resulting in the formation of catalytic-augmented Cu3+ by-product, thanks to the reactive bond force field molecular dynamics studies confirmed by ab-initio calculations and experimental observations. 相似文献
846.
Paweł Wajer Edyta Woźniak Wlodek Kofman Marcin Rybicki Stanisław Lewiński 《International journal of remote sensing》2018,39(9):2671-2689
This study uses the ray tracing method to simulate synthetic aperture radar (SAR) images of urban areas. The images are constructed for polarisations: horizontal-horizontal (HH) and vertical-vertical (VV), and different types of buildings, vegetation, and streets. Simulated images of a given area are compared with real SAR images of the same area acquired by the TerraSAR-X satellite. The simulations use the measured backscatter coefficient for HH and VV polarisations and for five different classes of terrain: houses, trees, shrubs, grass, and ground. For multiple reflections, we apply the generalized bistatic Lambertian model. The results show that, despite the limits of the ray tracing method and the approximations involved in modelling three-dimensional objects in the simulated scene, the simulated SAR images correspond well with the actual scene. All features present in the real image are reproduced in the simulated image; in particular, the double reflections of buildings and the surrounding ground appear clearly. However, discrepancies exist, and these are also discussed. 相似文献
847.
Marcin Janaszewski Author Vitae Michel Couprie Author Vitae 《Pattern recognition》2010,43(10):3548-2238
The construction of hole filling (or hole segmentation) method for 3D volumetric images is a new challenging issue in computer science. It needs a geometrical approach since from a topological point of view 3D holes (tunnels) are not well-delimited subsets of three dimensional space. In this paper, the authors propose an original, efficient, flexible algorithm of hole filling for volumetric objects. The algorithm has been tested on artificial objects and very complicated crack propagation tomography images. The qualitative results, quantitative results and features of proposed approach are presented in the paper. According to our knowledge it is the first algorithm of hole filling for volumetric objects. 相似文献
848.
Musculus longissimus dorsi (L) originating from 6 genotype groups of pigs was examined. Three among these were parental lines: Pietrain (Pi), Duroc (D), Polish Large White × Polish Landrace (PLW × PL), the other three crossbreeds obtained by crossing the aforementioned parental lines: (PLW × PL) × Pi, (PLW × PL) × (Pi × D) and (PLW × PL) × (D × Pi). It was found that there exists a variety of numbers and sizes of giant fibres and sizes of muscle fibres in the L muscle of the groups of animals, which results in a diversity of quality and susceptibility to massaging. The largest number of giant fibres and the greatest sizes of normal and giant fibres, along with the largest losses after heat treatment, the highest hardness, shear force, the lowest juiciness and attractiveness were found in the L muscle of Pi. Muscle of this breed was characterised by the least change in quality indicators during massaging. The decrease of Pi breed genes in the crossbreed genotype, resulted in reduction in the quantity of giant fibres and fibre sizes in comparison with pure Pi breed, which increased quality of crossbreeds’ muscles and their susceptibility to massaging. 相似文献
849.
850.
The numerical model of a thermoemission ion source was used for source ionization efficiency calculations. The dependency of ionization efficiency on working parameters like ionizer length and extraction voltage was discussed, and a good agreement with theoretical predictions was achieved. It was shown that increasing the ionizer length does not significantly change the obtained ionization efficiency. Extraction voltages up to a few thousand of volts are sufficient to obtain reasonable efficiency. 相似文献