Informacja

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

Wyszukujesz frazę "Lü, X." wg kryterium: Autor


Wyświetlanie 1-4 z 4
Tytuł:
Transient stability analysis and control of power systems with considering flux decay by energy function approach
Autorzy:
Lu, D.
Zhang, X.
Powiązania:
https://bibliotekanauki.pl/articles/201016.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
transient stability
dynamic performance
flux decay
structure preserving models
energy function
Opis:
In this paper, transient stability of power systems with structure preserving models is considered. A Hamiltonian function which can be regarded as a Lyapunov function for the system is proposed. Based on this, the influence of flux decay dynamics, especially during a fault, on transient stability is analyzed. With the increase of load power, the variation of stability boundary in the rotor angle/Eq plane is shown. The Energy-based excitation control, aiming at injecting additional damping into the post-fault system may reduce the critical clearing time (CCT). This can be demonstrated by the comparison of different flux decay dynamics in the fault-on condition, and the reason is illustrated by the relationship between rotor angle/Eq and the stability boundary. An improved control strategy is proposed and applied to increase the CCT. Simulation results verify that improvement is obtained both in transient stability and dynamic performance.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 1; 3-8
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fast near-infrared palmprint recognition using nonnegative matrix factorization extreme learning machine
Autorzy:
Xu, X.
Zhang, X.
Lu, L.
Deng, W.
Zuo, K
Powiązania:
https://bibliotekanauki.pl/articles/173572.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
extreme learning machine
palmprint recognition
superior speed
support vector machine (SVM)
Opis:
Support vector machine and artificial neural network are widely used in classification applications. Extreme learning machine (ELM) is a novel and efficient learning algorithm based on the generalized single hidden layer feed forward networks, which performs well in classification applications. The research results have shown the superiority of ELM with the existing classical algorithms: support vector machine (SVM) and back propagation neural network. In this study, we firstly propose a novel nonnegative matrix factorization extreme learning machine (NMFELM) to improve the performance of standard ELM method. Then we propose a novel near-infrared palmprint recognition approach based on NMFELM classifier. As the test data, we use the near-infrared palmprint database provided by Hong Kong Polytechnic University. The experimental results demonstrate that the proposed NMFELM method outperforms the standard ELM- and SVM-based methods.
Źródło:
Optica Applicata; 2014, 44, 2; 285-298
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimum design of fiber angle and hole orientation of an orthotropic plate
Autorzy:
Zhang, X.
Lu, A.
Wang, S.
Zhang, N.
Powiązania:
https://bibliotekanauki.pl/articles/280011.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
orthotropic plate
fiber orientation angle
hole orientation angle
conformal transformation method
differential evolution algorithm
Opis:
With the goal of decreasing the stress concentration along the hole boundary in an orthotropic plate under inequi-biaxial loadings, an optimum design of the fiber angle and hole orientation is presented. The maximum absolute tangential stress along the hole boundary is taken as the objective function, and the fiber orientation angle and the hole orientation angle are considered as design variables. The conformal transformation method of a complex function and the Differential Evolution (DE) algorithm are used. Two non-circular shapes, ellipse and hexagon are taken as examples to analyze the problem. Based on the results, we can conclude that the major axis of elliptical holes should be designed in the direction of the maximum external loading for a perforated structure in an orthotropic plate. However, the principal direction that has the larger Young’s modulus should be inclined to the direction of the minimum loading, especially for a significantly orthotropic plate.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 1; 297-311
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new troodontid theropod from the Late Cretaceous of central China, and the radiation of Asian troodontids
Autorzy:
Lu, J
Xu, L.
Liu, Y.
Zhang, X.
Jia, S.
Ji, Q.
Powiązania:
https://bibliotekanauki.pl/articles/20912.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new theropod
Late Cretaceous
Central China
Asian troodontid
troodontid
Theropoda
Troodontidae
Xixiasaurus
Cretaceous
Henan province
China
paleontology
Opis:
A new troodontid dinosaur, Xixiasaurus henanensis gen. et sp. nov., from the Upper Cretaceous Majiacun Formation of the Xixia Basin, Henan Province, is erected, based on a partial skull. It is characterized by bearing 22 maxillary teeth, a distinct opening on the lateral surface of the base of nasal process of the premaxilla, the rostral end of the upper jaw forming a tapered U−shape, and the mandibular symphyseal region slightly inflected medially. Xixiasaurus is most closely related to the Mongolian Byronosaurus among troodontids. Byronosaurus, Urbacodon, and Xixiasaurus may form a new clade, suggesting an endemic radiation of troodontids across Asia, including multiple taxa without dental serrations. The discovery of Xixiasaurus in the Xixia Basin may imply that the Xixiasaurus−bearing Majiacun Formation is Campanian in age.
Źródło:
Acta Palaeontologica Polonica; 2010, 55, 3; 381-388
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    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