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Wyszukujesz frazę "Qian, D." wg kryterium: Autor


Wyświetlanie 1-13 z 13
Tytuł:
Wave Propagation in a LRPC Composite Double Panel Structure with Periodically Attached Pillars and Etched Holes
Autorzy:
Qian, D.
Powiązania:
https://bibliotekanauki.pl/articles/176620.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
locally resonant phononic crystal
composite double panel structure
band structure
displacement field
transmission power spectrum
“base-spring-mass” simplified model
Opis:
The locally resonant phononic crystal (LRPC) composite double panel structure (DPS) made of a twodimensional periodic array of a two-component cylindrical LR pillar connected between the upper and lower composite plates is proposed. The plates are composed of two kinds of materials and periodically etched holes. In order to reveal the bandgap properties of structure theoretically, the band structures, displacement fields of eigenmodes and transmission power spectrums of corresponding 8 × 8 finite structure are calculated and displayed by using finite element method (FEM). Numerical results and further analysis demonstrate that if the excitation and response points are picked on different sides of the structure, a wide band gap with low starting frequency is opened, which can be treated as the coupling between dominant vibrations of pillars and plate modes. In addition, the influences of filled-in rubber, etched hole and viscidity of soft material on band gap are studied and understood with the help of “base-spring-mass” simplified model.
Źródło:
Archives of Acoustics; 2018, 43, 4; 717-725
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bandgap properties in locally resonant phononic crystal double panel structures with periodically attached pillars
Autorzy:
Qian, D.
Shi, Z.
Powiązania:
https://bibliotekanauki.pl/articles/280927.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
bandgap property
phononic crystal double panel
band structure
displacement field
transmission power spectrum
Opis:
The locally resonant (LR) phononic crystal double panel structure made of a two-dimensional periodic array of a two-component cylindrical LR pillar connected between the upper and lower plates is proposed, and the bandgap properties of the structure are investigated theoretically in this paper. The band structures, displacement fields of eigenmodes and transmission power spectrums of the corresponding 8×8 finite structure are calculated by the finite element method. Numerical results and further analysis demonstrate that a band gap with a low starting frequency and a wide band width is opened by the coupling between dominant vibrations of the pillars and plate modes of the upper and lower plates when the vibration source and the receiver are considered on different sides of the structure. By comparing the band structures and displacement fields of the double panel and those of the single plate with the same parameters, many common characteristics are displayed. Then, the influence of geometrical parameters on the band gap are studied and understood with the help of a simple ‘spring-mass’ model.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 4; 1167-1179
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using PWE/FE Method to Calculate the Band Structures of the Semi-Infinite PCs : Periodic in x-y Plane and Finite in z–direction
Autorzy:
Qian, D.
Shi, Z.
Powiązania:
https://bibliotekanauki.pl/articles/176974.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
semi-infinite phononic crystal
coupled plane wave expansion
finite element method
band structure
Opis:
This paper introduces the concept of semi-infinite phononic crystal (PC) on account of the Infinite periodicity in x-y plane and finiteness in z-direction. The plane wave expansion and finite element methods are coupled and formulized to calculate the band structures of the proposed periodic elastic composite structures based on the typical geometric properties. First, the coupled plane wave expansion and finite element (PWE/FE) method is applied to calculate the band structures of the Pb/rubber, steel/epoxy and steel/aluminum semi-infinite PCs with cylindrical scatters. Then, it is used to calculate the band structure of the Pb/rubber semi-infinite PC with cubic scatter. Last, the band structure of the rubbercoated Pb/epoxy three-component semi-infinite PC is calculated by the proposed method. Besides, all the results are compared with those calculated by the finite element (FE) method implemented by adopting COMSOL Multiphysics. Numerical results and further analysis demonstrate that the proposed PWE/FE method has strong applicability and high accuracy.
Źródło:
Archives of Acoustics; 2017, 42, 4; 735-742
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hierarchical sliding mode control for a class of SIMO under-actuated systems
Autorzy:
Qian, D.
Yi, J.
Zhao, D.
Powiązania:
https://bibliotekanauki.pl/articles/971008.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
control approaches
control applications
sliding mode control
underactuated systems
Opis:
A hierarchical sliding mode control approach is proposed for a class of SIMO under-actuated systems. This class of under-actuated systems is made up of several subsystems. Based on this physical structure, the hierarchical structure of the sliding surfaces is designed as follows. At first, the sliding surface of every subsystem is defined. Then the sliding surface of one subsystem is defined as the first layer sliding surface. The first layer sliding surface is used to construct the second layer sliding surface with the sliding surface of another subsystem. This process continues till the sliding surfaces of the entire subsystems are included. According to the hierarchical structure, the total control law is deduced by the Lyapunov theorem. In theory, the asymptotic stability of the entire system of sliding surfaces is proven and the parameter boundaries of the subsystem sliding surfaces are given. Simulation results show the feasibility of this control method through two typical SIMO under-actuated systems.
Źródło:
Control and Cybernetics; 2008, 37, 1; 159-175
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of simultaneous input-shaping-based SIRMs fuzzy control for double-pendulum-type overhead cranes
Autorzy:
Qian, D.
Tong, S.
Yang, B.
Lee, S.
Powiązania:
https://bibliotekanauki.pl/articles/953059.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
SIRMs fuzzy control
double-pendulum-type overhead cranes
sterowanie rozmyte
SIRM
suwnica wahadłowa
Opis:
Overhead cranes are extensively employed but their performance suffers from the natural sway of payloads. Sometime, the sway exhibits double-pendulum motions. To suppress the motions, this paper investigates the design of simultaneous input-shaping-based fuzzy control for double-pendulum-type overhead cranes. The fuzzy control method is based on the single input-rule modules (SIRMs). Provided the all the system variables are measurable, the SIRMs fuzzy controller is designed at first. To improve the performance of the fuzzy controller, the simultaneous input shaper is adopted to shape the control command generated by the fuzzy controller. Compared with other two control methods, i.e., the SIRMs fuzzy control and the convolved input-shaping-based SIRMs fuzzy control, simulation results illustrate the feasibility, validity and robustness of the presented control method for the anti-swing control problem of double-pendulum-type overhead cranes.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2015, 63, 4; 887-896
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Observer-based leader-following formation control of uncertain multiple agents by integral sliding mode
Autorzy:
Qian, D. W.
Tong, S. W.
Li, C. D.
Powiązania:
https://bibliotekanauki.pl/articles/201511.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
multi-agent system
formation control
integral sliding mode control
uncertainty
nonlinear disturbance observer
stability
system wieloagentowy
kontrola formacji
integralne sterowanie ślizgowe
niepewność
nieliniowy obserwator zakłóceń
stabilność
Opis:
This paper investigates the formation control problem of multiple agents. The formation control is founded on leader-following approaches. The method of integral sliding mode control is adopted to achieve formation maneuvers of the agents based on the concept of graph theory. Since the agents are subject to uncertainties, the uncertainties also challenge the formation-control design. Under a mild assumption that the uncertainties have an unknown bound, the technique of nonlinear disturbance observer is utilized to tackle the issue. According to a given communication topology, formation stability conditions are investigated by the observer-based integral sliding mode formation control. From the perspective of Lyapunov, not only is the formation stability guaranteed, but the desired formation of the agents is also realized. Finally, some simulation results are presented to show the feasibility and validity of the proposed control scheme through a multi-agent platform.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2017, 65, 1; 35-44
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chaos synchronization of uncertain coronary artery systems through sliding mode
Autorzy:
Qian, D. W.
Xi, Y. F.
Tong, S. W.
Powiązania:
https://bibliotekanauki.pl/articles/201501.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
chaos synchronization
coronary artery systems
sliding mode control
nonlinear dynamics
synchronizacja chaosu
system tętnic wieńcowych
kontroler trybu przesuwnego
dynamika nieliniowa
Opis:
The chaotic phenomena of coronary artery systems are hazardous to health and may induce illness development. From the perspective of engineering, the potential harm can be eliminated by synchronizing chaotic coronary artery systems with a normal one. This paper investigates the chaos synchronization problem in light of the methodology of sliding mode control (SMC). Firstly, the nonlinear dynamics of coronary artery systems are presented. Since the coronary artery systems suffer from uncertainties, the technique of derivative-integral terminal SMC is employed to achieve the chaos synchronization task. The stability of such a control system is proven in the sense of Lyapunov. To verify the feasibility and effectiveness of the proposed method, some simulation results are illustrated in comparison with a benchmark.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 3; 455-462
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the Rasch model in categorical pedigree analysis using MCEM: I binary data
Autorzy:
Qian, G.
Huggins, R.
Loesch, D.
Powiązania:
https://bibliotekanauki.pl/articles/729756.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
pedigree analysis
binary data
MCEM algorithm
Metropolis-Hastings algorithm
Opis:
An extension of the Rasch model with correlated latent variables is proposed to model correlated binary data within families. The latent variables have the classical correlation structure of Fisher (1918) and the model parameters thus have genetic interpretations. The proposed model is fitted to data using a hybrid of the Metropolis-Hastings algorithm and the MCEM modification of the EM-algorithm and is illustrated using genotype-phenotype data on a psychological subtest in families where some members are affected by the genetic disorder fragile X. In addition, hypothesis testing and model selection methods based on the Wald statistic are discussed.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2004, 24, 2; 255-280
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Event-related desynchronization/synchronization-based volitional cursor control in a two-dimensional center-out paradigm
Autorzy:
Huang, D.
Qian, K.
Oxenham, S.
Fei, D. -Y.
Bai, O.
Powiązania:
https://bibliotekanauki.pl/articles/1396737.pdf
Data publikacji:
2012
Wydawca:
Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
Tematy:
brain-computer interface
BCI
two-dimensional
two-dimensional BCI control
event-related synchronization
event-related desynchronization
EEG
Opis:
To achieve a reliable two-dimensional control by noninvasive EEG-based brain-computer interface (BCI), users are typically required to receive long-term training to learn effective regulation of their brain rhythmic activities, and to maintain sustained attention during the operation. We proposed a two-dimensional BCI using event-related desynchronization and event-related synchronization associated with human natural behavior so that users need neither long-term training nor high mental loads to maintain concentration. In this study, we intended to further investigate the performance of the proposed BCI associated with either physical movement or motor imagery with an online two-dimensional centerout cursor control paradigm. Model adaptation method was employed for better decoding of human movement intention from EEG activities. The results demonstrated an effective center-out cursor control: as high as 77.1% during online control with physical movement and 57.3% with motor imagery. It suggests that two-dimensional BCI control can be achieved without long-term training.
Źródło:
Journal of Artificial Intelligence and Soft Computing Research; 2012, 2, 2; 97-108
2083-2567
2449-6499
Pojawia się w:
Journal of Artificial Intelligence and Soft Computing Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxidative stress induced by cobalt in Jatropha curcas seedlings: response of growth and chemical changes
Autorzy:
Hu, Y.
Song, Y.
Yu, D.
Qian, W.
He, M.
Yi, L.
Gao, S.
Powiązania:
https://bibliotekanauki.pl/articles/53687502.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Opis:
Experiments using in vitro embryo germination and culture have been designed to investigate the effects of cobalt levels of 0, 100, 200, 400 and 800 μM on some growth parameters and chemical changes in Jatropha curcas seedlings. The results showed that excess cobalt levels in MS media produced visual symptoms of toxicity in J. curcas seedlings after 7 d with increasing levels of cobalt ion. The fresh weights of cotyledons and radicles were significantly affected except for hypocotyls at the cobalt concentration of 100 μM. The activity of superoxide dismutase (SOD) significantly increased in the radicles when compared to the control, but decreases in the activity of the hypocotyls were found at the tested cobalt levels. Increase of guaiacol peroxidase (GPX) activity in the cotyledons and hypocotyls was observed at the tested cobalt levels, but a decrease of the activity in the radicles except for at cobalt concentration of 100 μM. Increase in the activity of catalase (CAT) of radicles with increasing cobalt concentrations, and a significant decrease in activity in the hypocotyls was also observed. Increase in phenylalanine ammonia-lyase (PAL) activity of cotyledons and radicles with increasing cobalt concentrations in the range 100-800 μM, but a decline in the activity of hypocotyls was also observed when hypocotyls at the cobalt concentrations of 400 and 800 μM. The present results indicated that SOD, GPX, CAT, and PAL may play an important role in the defensive mechanisms of Jatropha curcas seedlings exposed to excessive cobalt. These findings will help to provide useful bioassays to help in assessment of cobalt contamination in agricultural environments.
Źródło:
Journal of Elementology; 2023, 28, 4; 1037-1053
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nutritional components and antioxidant activities of Firmiana platanifolia seeds in response to different germination times
Autorzy:
Zhi, X.M.
Qian, W.Z.
Song, Y.
Mu, C.J.
Yu, D.S.
Lin, X.
Gao, S.
Powiązania:
https://bibliotekanauki.pl/articles/53374817.pdf
Data publikacji:
2024
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Opis:
Germination can be used to enhance nutritional value and health functions of edible seeds. Sprouts are considered healthier than non-germinated seeds because they are richer in the basic nutritional components (protein, amino acid, carbohydrates, and minerals) and also contain more bioactive components. The present study is the first to dynamically analyze the germination properties regarding morphological characteristics, nutrient compounds, bioactive components and antioxidant activities of Firmiana platanifolia (F. platanifolia) seeds. The results showed that the appearance, color and morphology of F. platanifolia seeds and sprouts at different germination times showed considerable differences. With the increasing germination time, the moisture content, sucrose, fructose, total flavonoid content and DPPH significantly increased, and reached the peak at 8 d of germination, almost 2.38, 5.76, 4.02, 7.97 and 8.91 times higher than those of at 0 d, respectively. The soluble protein, total phenolic, ABTS and ferric reducing antioxidant power (FRAP) increased first and then decreased as the germination time increased, and were overall higher than those of at the initial concentration. However, total starch content and mineral elements decreased as germination progressed. Additionally, the total flavonoid content showed a strongly positive correlation with DPPH (p<0.01), whereas the total phenolic and total flavonoid content showed a similar, significant and positive correlation with ABTS and ferrous ion chelating activity (FICA, p<0.05). Therefore, seed germination significantly increased phytochemical contents and antioxidant activity. The current research results will help to reveal the dynamic changes in nutrient content and antioxidant activity of F. platanifolia seeds during the germination process, and provide reference data for further studying the development and utilization of germinated seeds.
Źródło:
Journal of Elementology; 2024, 29, 1; 193-212
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Studies on Charging Operation of a Compact Repetitive Tesla Transformer
Autorzy:
Zhang, Z.
Zhang, J.
Yang, H.
Qian, B.
Meng, Z.
Li, D.
Wang, S.
Cao, Y.
Zhou, W.
Powiązania:
https://bibliotekanauki.pl/articles/1807860.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
84.30.Ng
84.30.Jc
84.30.Qi
84.70.+p
Opis:
Charging operations of a compact Tesla transformer were experimentally investigated, in single-shot and rep-rate (50 pps for 1 s) modes, respectively. The charging limitations were also explored. The experimental results were compared and analyzed. The maximum secondary charging voltages of the Tesla transformer were measured to be 380 kV and 300 kV in single-shot and rep-rate modes, respectively. The RMS pulse-to-pulse instability of the secondary charging voltage is generally less than 10% but increases with the increasing initial voltage across the primary capacitor. Since the secondary capacitor of the Tesla transformer is a pulse forming line (PFL), continued operation is possible if there is breakdown in the PFL. Furthermore, operation can even be continued under occasional breakdown for some pulses, without the effects on the operations of subsequent pulses.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 973-975
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of serum adiponectin and leptin in healthy perinatal dairy cows or cows with ketosis, and their effectson ketosis involved indices
Autorzy:
Shen, L.
Qian, B.
Xiao, J.
Zhu, Y.
Hussain, S.
Deng, J.
Peng, G.
Zuo, Z.
Zou, L.
Yu, S.
Ma, X.
Zhong, Z.
Ren, Z.
Wang, Y.
Liu, H.
Zhou, Z.
Cai, D.
Hu, Y.
Zong, X.
Cao, S.
Powiązania:
https://bibliotekanauki.pl/articles/2087289.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adiponectin
dairy cows
ketosis
leptin
perinatal period
Źródło:
Polish Journal of Veterinary Sciences; 2020, 23, 3; 373-381
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-13 z 13

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