Autor: Xu, L. - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Global convergence analysis of impulsive fractional order difference systems
Autorzy:: He, D.
Xu, L.
Tematy:: impulsive fractional difference systems
discrete Mittag-Leffler function
Z-transform
convergence
konwergencja
funkcja Mittag-Lefflera
transformacja Z; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/200405.pdf Link otwiera się w nowym oknie
Opis:: This paper is designed to deal with the convergence and stability analysis of impulsive Caputo fractional order difference systems. Using the Lyapunov functions, the Z-transforms of Caputo difference operators, and the properties of discrete Mittag-Leffler functions, some effective criteria are derived to guarantee the global convergence and the exponential stability of the addressed systems.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Integrated system of health management-oriented reliability prediction for a spacecraft software system with an adaptive genetic algorithm support vector machine
Zorientowane na zintegrowane zarządzanie kondycją systemu prognozowanie niezawodności systemów oprogramowania statków kosmicznych z wykorzystaniem opartej na adaptacyjnym algorytmie genetycznym maszyny wektorów nośnych
Autorzy:: Xu, J.
Meng, Z
Xu, L.
Tematy:: spacecraft software system
reliability
integrated system health management
adaptive genetic algorithms support vector machine
system oprogramowania statku kosmicznego
niezawodność
zintegrowane zarządzanie kondycją systemu
adaptacyjne algorytmy genetyczne
maszyna wektorów nośnych; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Powiązania:: https://bibliotekanauki.pl/articles/300804.pdf Link otwiera się w nowym oknie
Opis:: Software reliability prediction is very important to minimize cost and improve software development effectiveness, especially in a spacecraft’s software system. In this paper, a new spacecraft software system reliability definition is given and a new reliability prognostics-oriented life cycle integrated system health management for a spacecraft software system is focused on. Adaptive genetic algorithms are then combined with a support vector machine to build an adaptive genetic algorithm support vector machine reliability prediction model. This model attempts to overcome the genetic algorithm weaknesses, such as the local minima and premature convergence problems, and solves the parameter selection difficulties often encountered in a support vector machine. After construction, the proposed adaptive genetic algorithm support vector machine model is employed to predict the reliability of a spacecraft software system. Finally, a numerical example is given to show how the proposed approach has a superior prediction performance compared to a standard support vector machine and artificial neural network.
Przewidywanie niezawodności oprogramowania odgrywa ważną rolę w minimalizowaniu kosztów i poprawie efektywności tworzenia oprogramowania, zwłaszcza w odniesieniu do systemów oprogramowania statków kosmicznych. W niniejszej pracy, podano nową definicję niezawodności systemu oprogramowania statku kosmicznego koncentrując uwagę na opartym na prognozowaniu niezawodności oraz cyklu życia modelu zintegrowanego zarządzania kondycją systemu opracowanego dla systemu oprogramowania statku kosmicznego. Skonstruowano następnie model przewidywania niezawodności oparty na połączeniu adaptacyjnych algorytmów genetycznych oraz maszyny wektorów nośnych. Model ten stanowi próbę przezwyciężenia słabości algorytmów genetycznych, takich jak problem minimów lokalnych czy problem przedwczesnej zbieżności, a także rozwiązania trudności związanych z doborem parametrów, jakie często występują przy zastosowaniu maszyny wektorów nośnych. Skonstruowany model opartej na adaptacyjnym algorytmie genetycznym maszyny wektorów nośnych zastosowano do przewidywania niezawodności systemu oprogramowania statku kosmicznego. Wreszcie, przedstawiono przykład liczbowy, który pokazuje że opracowany model charakteryzuje się wyższą dokładnością prognozowania w porównaniu do standardowej maszyny wektorów nośnych oraz sztucznej sieci neuronowej.
Dostawca treści:: Biblioteka Nauki

Artykuł

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Skocz do pozycji: 3.

Tytuł:: Quartz enhanced photoacoustic spectroscopy based on an external cavity quantum cascade laser
Autorzy:: Xu, L.
Zhou, S.
He, T.
Li, J.
Tematy:: external cavity quantum cascade laser
ECQCL
quartz enhanced photoacoustic spectroscopy
QEPAS
volatile organic compound
VOC
ethanol; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/173669.pdf Link otwiera się w nowym oknie
Opis:: Mid-infrared laser spectroscopy is a powerful analytical tool for trace gases detection. In this study, a spectroscopic system based on an external cavity quantum cascade laser (ECQCL) and quartz enhanced photoacoustic spectroscopy (QEPAS) was developed for volatile organic compounds (VOCs) measurements. Primary laboratory test on ethanol spectroscopy was investigated and compared with traditional direct absorption spectroscopy (DAS). Experimental results show that the proposed QEPAS is more sensitive than the conventional DAS method. In addition, the significant linear dependence of photoacoustic signal on sample pressures and laser operating parameters was observed.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: The Jiyuan tetrapod fauna of the Upper Permian of China: new pareiasaur material and the reestablishment of Honania complicidentata
Autorzy:: Xu, L.
Li, X.-W.
Jia, S.-H.
Liu, J.
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/22012.pdf Link otwiera się w nowym oknie
Opis:: Honania complicidentata and Tsiyuania simplicidentata are pareiasaur taxa based on material from the Shangshihezi Formation of Jiyuan, Henan Province, China that were earlier designated as nomina vana. Based on the study of new material, and the reexamination of old specimens, we determine that the pareiasaur material from Jiyuan represents a single species that differs from all known species from other localities. Thus, we resurrect the name H. complicidentata for the material from Jiyuan. H. complicidentata is characterized by maxillary teeth with high crowns, dentary teeth slightly posteriorly inclined compared to the dentary dorsal margin, nearly all preserved marginal teeth have a cusped cingulum on the lingual surface, and humerus without an ectepicondylar foramen. Phylogenetic analysis shows Honania is more basal than Shansisaurus and Shihtienfenia from the Sunjiagou Formation of China.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Mirror surface finishing of hardened die steel by high-Power ultrasonic elliptical vibration cutting
Autorzy:: Jung, H.
Shamoto, E.
Ueyama, T.
Hamada, S.
Xu, L.
Tematy:: elliptical vibration cutting
mirror surface finishing
hardened steel; Pokaż więcej
Wydawca:: Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Powiązania:: https://bibliotekanauki.pl/articles/100101.pdf Link otwiera się w nowym oknie
Opis:: Ultrasonic elliptical vibration cutting has recently been utilized in industry for finishing of various precision parts such as mirror surface finishing and precision micro machining of dies and molds. However, its application has been limited to high-cost ultra-precision machining, where depth of cut is typically in a range from a few micrometers to several tens of micrometers due to power limitation of the vibration device. To expand its application to low-cost mirror surface finishing with ordinary machining facilities, a high-power elliptical vibration device was developed in this research. The elliptical vibration cutting of hardened die steel was examined by applying the developed high-power elliptical vibration device with single crystalline diamond tools. Pick feed was kept to be 0.02 mm to obtain mirror quality surfaces, while depth of cut was increased up to 0.4 mm to verify performance of the high-power elliptical vibration cutting. By analyzing the experimental results, it was clarified that mirror surface finishing of the hardened die steel can be achieved at the large depth of cut with practically acceptable tool life.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: A practical application of kernel-based fuzzy discriminant analysis
Autorzy:: Gao, J. Q.
Fan, L. Y.
Li, L.
Xu, L. Z.
Tematy:: analiza dyskryminacyjna
algorytm najbliższego sąsiada
SVD
kernel fuzzy discriminant analysis
fuzzy k-nearest neighbor
QR decomposition
singular value decomposition (SVD)
fuzzy membership matrix
t-test; Pokaż więcej
Wydawca:: Uniwersytet Zielonogórski. Oficyna Wydawnicza
Powiązania:: https://bibliotekanauki.pl/articles/908344.pdf Link otwiera się w nowym oknie
Opis:: A novel method for feature extraction and recognition called Kernel Fuzzy Discriminant Analysis (KFDA) is proposed in this paper to deal with recognition problems, e.g., for images. The KFDA method is obtained by combining the advantages of fuzzy methods and a kernel trick. Based on the orthogonal-triangular decomposition of a matrix and Singular Value Decomposition (SVD), two different variants, KFDA/QR and KFDA/SVD, of KFDA are obtained. In the proposed method, the membership degree is incorporated into the definition of between-class and within-class scatter matrices to get fuzzy between-class and within-class scatter matrices. The membership degree is obtained by combining the measures of features of samples data. In addition, the effects of employing different measures is investigated from a pure mathematical point of view, and the t-test statistical method is used for comparing the robustness of the learning algorithm. Experimental results on ORL and FERET face databases show that KFDA/QR and KFDA/SVD are more effective and feasible than Fuzzy Discriminant Analysis (FDA) and Kernel Discriminant Analysis (KDA) in terms of the mean correct recognition rate.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: An efficient connected dominating set algorithm in WSNs based on the induced tree of the crossed cube
Autorzy:: Zhang, J.
Xu, L.
Zhou, S. M.
Wu, W.
Ye, X.
Tematy:: wireless sensor networks
connected dominating set
induced tree
approximation algorithm
crossed cube
bezprzewodowa sieć sensorowa
podgrafy indukowane
algorytm aproksymacyjny; Pokaż więcej
Wydawca:: Uniwersytet Zielonogórski. Oficyna Wydawnicza
Powiązania:: https://bibliotekanauki.pl/articles/330830.pdf Link otwiera się w nowym oknie
Opis:: The connected dominating set (CDS) has become a well-known approach for constructing a virtual backbone in wireless sensor networks. Then traffic can forwarded by the virtual backbone and other nodes turn off their radios to save energy. Furthermore, a smaller CDS incurs fewer interference problems. However, constructing a minimum CDS is an NP-hard problem, and thus most researchers concentrate on how to derive approximate algorithms. In this paper, a novel algorithm based on the induced tree of the crossed cube (ITCC) is presented. The ITCC is to find a maximal independent set (MIS), which is based on building an induced tree of the crossed cube network, and then to connect the MIS nodes to form a CDS. The priority of an induced tree is determined according to a new parameter, the degree of the node in the square of a graph. This paper presents the proof that the ITCC generates a CDS with a lower approximation ratio. Furthermore, it is proved that the cardinality of the induced trees is a Fibonacci sequence, and an upper bound to the number of the dominating set is established. The simulations show that the algorithm provides the smallest CDS size compared with some other traditional algorithms.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Flotation separation of cervantite from quartz
Autorzy:: Wang, J.
Hua, Y.
Yu, S.
Xiao, J.
Xu, L.
Wang, Z.
Tematy:: cervantite
quartz
dodecylamine
flotation
density functional theory; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/110941.pdf Link otwiera się w nowym oknie
Opis:: Flotation separation of cervantite (Sb2O4) from quartz was investigated using dodecylamine (DDA) as a collector. Experiments were conducted on single minerals and on a synthetic mixture of quartz and cervantite. Flotation separation mechanisms were investigated using the zeta potential technique, solution chemistry principles, density functional calculations and Fourier Transform Infrared (FT-IR) spectroscopy. The results indicated that DDA, primarily in the form of molecules, exhibited excellent performance in flotation of cervantite and quartz at pH 10.5. The adsorption energy of the DDA molecules on the cervantite surface was greater than the adsorption energy of water molecules, while the adsorption energy of DDA on the quartz surface was less than the adsorption energy of water molecules. DDA molecules can be adsorbed on the quartz surface to a certain extent, but it was difficult for the same molecule to be adsorbed on the cervantite surface in the pulp. This resulted in flotation of quartz. DDA molecules were adsorbed on quartz not only through physical adsorption but also by hydrogen bonding. However, cervantite could not be floated at pH 10.5 since adsorption of DDA molecules occurred through weak physical bonds on cervantite.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

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.
Tematy:: new theropod
Late Cretaceous
Central China
Asian troodontid
troodontid
Theropoda
Troodontidae
Xixiasaurus
Cretaceous
Henan province
China
paleontology; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/20912.pdf Link otwiera się w nowym oknie
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.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Intelligent decision system based on the evidential reasoning approach and its applications
Autorzy:: Xu, D. L.
Yang, J. B.
Tematy:: multicriteria decision support systems
knowledge management
intelligent decision system
evidential reasoning approach; Pokaż więcej
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Powiązania:: https://bibliotekanauki.pl/articles/308996.pdf Link otwiera się w nowym oknie
Opis:: Intelligent decision system (IDS) is a window-based software package that has been developed on the basis of the evidential reasoning (ER) approach, a recent development in handling hybrid multiple criteria decision analysis (MCDA) problems with uncertainties. In this paper, the evidential reasoning approach will be briefly described first, and its major differences from and the relationships with conventional MCDA methods will also be discussed. Then the main features, advantages and benefits of IDS will be demonstrated and explained using two application examples: supplier pre-qualification assessment and customer satisfaction survey analysis, which have been investigated as part of the research projects led by the authors and funded by the UK government and the EC. It is concluded in the paper that the ER approach can be used not only to deal with problems that traditional methods can solve, but also to model and analyse more complicated decision problems that traditional methods are incapable of handling.
Dostawca treści:: Biblioteka Nauki

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