Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Kraft, A." wg kryterium: Autor


Tytuł:
On augmenting the visual slam with direct orientation measurement using the 5-point algorithm
Autorzy:
Schmidt, A.
Kraft, A.
Fularz, M.
Domagała, Z.
Tematy:
visual SLAM
visual odometry
Pokaż więcej
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Powiązania:
https://bibliotekanauki.pl/articles/384310.pdf  Link otwiera się w nowym oknie
Opis:
This paper presents the attempt to merge two paradigms of the visual robot navigation: Visual Simultaneous Localization and Mapping (VSLAM) and Visual Odometry (VO). The VSLAM was augmented with the direct, visual measurement of the robot orientation change using the 5-point algorithm. The extended movement model of the robot was proposed and additional measurements were introduced to the SLAM system. The efficiency of the 5-point and 8-point algorithms was compared. The augmented system was compared with the state of the art VSLAM solution and the proposed modification allowed to reduce the tracking error by over 30%.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative assessment of point feature detectors in the context of robot navigation
Autorzy:
Schmidt, A.
Kraft, M.
Fularz, M.
Domagała, Z.
Tematy:
point features
detectors
descriptors
Pokaż więcej
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Powiązania:
https://bibliotekanauki.pl/articles/950804.pdf  Link otwiera się w nowym oknie
Opis:
This paper presents evaluation of various contemporary interest point detector and descriptor pairs in the context of robot navigation. The robustness of the detectors and descriptors is assessed using publicly available datasets: the first gathered from the camera mounted on the industrial robot [17] and the second gathered from the mobile robot [20]. The most efficient detectors and descriptors for the visual robot navigation are selected.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The registration system for the evaluation of indoor visual slam and odometry algorithms
Autorzy:
Schmidt, A.
Kraft, M.
Fularz, M.
Domagała, Z.
Tematy:
SLAM
visual odometry
benchmark
Pokaż więcej
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Powiązania:
https://bibliotekanauki.pl/articles/384854.pdf  Link otwiera się w nowym oknie
Opis:
This paper presents the new benchmark data registra- tion system aimed at facilitating the development and evaluation of the visual odometry and SLAM algorithms. The WiFiBOT LAB V3 wheeled robot equipped with three cameras, XSENS MTi atitude and heading reference system (AHRS) and Hall encoders can be used to gather data in indoor exploration scenarios. The ground truth trajectory of the robot is obtained using the visual motion tracking system. Additional static cameras simulating the surveillance network, as well as artificial markers augmen ting the navigation are incorporated in the system. The datasets registered with the presented system will be freely available for research purposes.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sprzętowy układ do estymacji siły oraz zmęczenia mięśni na podstawie sygnału elektromiograficznego
A hardware system for muscle force and tiredness estimation from electromyo-graphic signal
Autorzy:
Kraft, M.
Fularz, M.
Kaczmarek, P.
Schmidt, A.
Tematy:
FPGA
elektromiografia
EMG
force and fatigue estimation
Pokaż więcej
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Powiązania:
https://bibliotekanauki.pl/articles/156364.pdf  Link otwiera się w nowym oknie
Opis:
W pracy przedstawiono implementację układu służącego do estymacji siły oraz zmęczenia mięśni na podstawie sygnału elektromiograficznego (EMG), rejestrowanego za pomocą dwukanałowego wzmacniacza, oraz położenia stawu mierzonego za pomocą enkodera kwadraturowego. W matrycy FPGA zaimplementowano struktury obliczające aktualną wartość średniej częstotliwości (MNF) oraz wartości średniokwadratowej (RMS) sygnału i kąta, co umożliwia estymację aktualnej siły oraz zmęczenia. Opracowane rozwiązanie jest skalowalne i umożliwia równoległą obsługę liczby kanałów ograniczonej wyłącznie zasobami matrycy FPGA.
This paper presents an FPGA implementation of the muscle force and fatigue estimation unit based on the analysis of an electromyography (EMG) signal measured with a two-channel amplifier and the joint position measured with a quadratic encoder. The contemporary systems use the root mean square (RMS) of the EMG signal and muscle length to estimate the contraction force and decrease in the median frequency of the EMG signal to detect the muscle fatigue [2]. The proposed system consists of (Fig. 1): an infinite impulse response (IIR) high-pass filter with the cut-off frequency of 10 Hz, a dedicated RMS calculation block for the 512 samples window (Fig. 2.), the Fast Fourier Transform (FFT) block and a MicroBlaze processor. The muscle length is estimated using measurements from the encoder placed on the joint. The mean value of the EMG signal frequencies is used as the approximation of the median-frequency. The system was tested using the Xilinx SP605 evaluation kit and the obtained results were verified. The resources usage is presented in Table 1. Due to the FPGA inherent ability to parallelize computation, additional measurement channels can be easily added without increase in the processing time. The presented system is portable and can be used as a part of any mobile solution requiring feedback from the muscles-state (e.g. exoskeleton). Due to its scalability, it can be easily extended into a larger muscle-analysis system. Moreover, it can be modified to facilitate analysis of other biomedical signals.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficient RGB-D data processing for feature-based self-localization of mobile robots
Autorzy:
Kraft, M.
Nowicki, M.
Penne, R.
Schmidt, A.
Skrzypczyński, P.
Tematy:
visual odometry
simultaneous localization
simultaneous mapping
RGB-D
tracking
point features
odometria wizyjna
lokalizacja jednoczesna
śledzenie
Pokaż więcej
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Powiązania:
https://bibliotekanauki.pl/articles/330295.pdf  Link otwiera się w nowym oknie
Opis:
The problem of position and orientation estimation for an active vision sensor that moves with respect to the full six degrees of freedom is considered. The proposed approach is based on point features extracted from RGB-D data. This work focuses on efficient point feature extraction algorithms and on methods for the management of a set of features in a single RGB-D data frame. While the fast, RGB-D-based visual odometry system described in this paper builds upon our previous results as to the general architecture, the important novel elements introduced here are aimed at improving the precision and robustness of the motion estimate computed from the matching point features of two RGB-D frames. Moreover, we demonstrate that the visual odometry system can serve as the front-end for a pose-based simultaneous localization and mapping solution. The proposed solutions are tested on publicly available data sets to ensure that the results are scientifically verifiable. The experimental results demonstrate gains due to the improved feature extraction and management mechanisms, whereas the performance of the whole navigation system compares favorably to results known from the literature.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Suboptimal codon pairs trigger ribosome collisions and cellular quality control responses in tRNA modification mutants
Autorzy:
Sin, Olga
Koziej, Łukasz
Drexler, Hannes C A
Mollet, Fabienne
Ranff, Tristan
Schöler, Hans R
Bruder, Jan M
Eggers, Cristian
Kraft, Claudine
Leidel, Sebastian A
Fufezan, Christian
Wu, Jie
Mancilla, Hector
Glatt, Sebastian
Opis:
Transfer RNA (tRNA) modifications tune translation rates and codon optimality, thereby optimizing co-translational protein folding. However, the mechanisms by which tRNA modifications modulate codon optimality and trigger phenotypes remain unclear. Here, we show that ribosomes stall at specific modification-dependent codon pairs in wobble uridine modification (U34) mutants. This triggers ribosome collisions and a coordinated hierarchical response of cellular quality control pathways. High-resolution ribosome profiling reveals an unexpected functional diversity of U34 modifications during decoding. For instance, 5-carbamoylmethyluridine (ncm5U) exhibits distinct effects at the A and P sites. Importantly, ribosomes only slow down at a fraction of codons decoded by hypomodified tRNA, and the decoding speed of most codons remains unaffected. However, the translation speed of a codon largely depends on the identity of A- and P-site codons. Stalling at modification-dependent codon pairs induces ribosome collisions, triggering ribosome-associated quality control (RQC) and preventing protein aggregation by degrading aberrant nascent peptides and messenger RNAs. Inactivation of RQC stimulates the expression of molecular chaperones that remove protein aggregates. Our results demonstrate that loss of tRNA modifications primarily disrupts translation rates of suboptimal codon pairs, showing the coordinated regulation and adaptability of cellular surveillance systems. These systems ensure efficient and accurate protein synthesis and maintain protein homeostasis.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
LOFAR Facet Calibration
Autorzy:
Best, P. N.
Bonafede, A.
Croston, J. H.
Orrú, E.
Miley, G. K.
Jarvis, M. J.
Rafferty, D. A.
Heald, G.
Ogrean, G. A.
Sridhar, S. S.
White, G. J.
Bîrzan, L.
Dijkema, T. J.
Murray, S. S.
Andrade-Santos, F.
Jones, C.
Brüggen, M.
van der Tol, S.
Sarazin, C. L.
Forman, W. R.
Chyży, Krzysztof
Sabater, J.
Intema, H. T.
Brunetti, G.
Dawson, W. A.
Ensslin, T.
Röttgering, H. J. A.
Simionescu, A.
van Weeren, R. J.
Rudnick, L.
Williams, W. L.
Ferrari, C.
de Gasperin, F.
Horellou, C.
Shimwell, T. W.
Hoeft, M.
Hardcastle, M. J.
Mevius, M.
Pizzo, R.
Kraft, R. P.
Cassano, R.
Stroe, A.
Opis:
LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short baseline coverage to map diffuse extended emission. However, producing high-quality deep images is challenging due to the presence of direction-dependent calibration errors, caused by imperfect knowledge of the station beam shapes and the ionosphere. Furthermore, the large data volume and presence of station clock errors present additional difficulties. In this paper we present a new calibration scheme, which we name facet calibration, to obtain deep high-resolution LOFAR High Band Antenna images using the Dutch part of the array. This scheme solves and corrects the direction-dependent errors in a number of facets that cover the observed field of view. Facet calibration provides close to thermal noise limited images for a typical 8 hr observing run at ∼ 5'' resolution, meeting the specifications of the LOFAR Tier-1 northern survey.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies