91,741 research outputs found
Model Predictive Current Control With Model-Aid Extended State Observer Compensation for PMSM Drive
Get PDFModel predictive current controller is a popular and effective technique to provide fast dynamic response in the field of motor control. However, conventional predictive controllers are susceptible to deteriorating control performance when model mismatch exists, such as changes in motor parameters due to the temperature variations. Therefore, this article proposes a precise model-aid extended state observer (MAESO) compensation-based real-time model predictive current controller with enhanced parameter robustness performance and high bandwidth. The predictive controller is converted into the form of multiparameter quadratic programming for online solution using numerical computational method and the constraints are linearized. In addition, the disturbances estimated by MAESO are fed back to the controller in the form of parameters for cycle-by-cycle compensation without extra controller design. Comparative simulations and experiments under different operating conditions are carried out to verify the effectiveness and superiority of the proposed method.Model predictive current controller is a popular and effective technique to provide fast dynamic response in the field of motor control. However, conventional predictive controllers are susceptible to deteriorating control performance when model mismatch exists, such as changes in motor parameters due to the temperature variations. Therefore, this article proposes a precise model-aid extended state observer (MAESO) compensation-based real-time model predictive current controller with enhanced parameter robustness performance and high bandwidth. The predictive controller is converted into the form of multiparameter quadratic programming for online solution using numerical computational method and the constraints are linearized. In addition, the disturbances estimated by MAESO are fed back to the controller in the form of parameters for cycle-by-cycle compensation without extra controller design. Comparative simulations and experiments under different operating conditions are carried out to verify the effectiveness and superiority of the proposed method
Z(c)(4025) as the hadronic molecule with hidden charm
No full textWe have studied the loosely bound D*(D) over bar* system. Our results indicate that the recently observed charged charmonium-like structure Z(c)(4025) can be an ideal D*(D) over bar* molecular state. We have also investigated its pionic, dipionic, and radiative decays. We stress that both the scalar isovector molecular partner Z(c0) and three isoscalar partners (Z) over tilde (c0,c1,c2) should also exist if Z(c)(4025) is a D*(D) over bar* molecular state in the framework of the one-pion-exchange model. Z(c0) can be searched for in the channel e(+)e(-) -> Y -> Z(c0)(4025)(pi pi)(P-wave) where Y can be Y(4260) or any other excited 1(--) charmonium or charmonium-like states such as Y(4360), Y(4660), etc. The isoscalar D*(D) over bar* molecular states (Z) over tilde (c0,c2) with 0(+)(0(++)) and 0(+)(2(++)) can be searched for in the three pion decay channel e(+)e(-) -> Y -> (Z) over tilde (c0,c2)(3 pi)(P-wave)(I=0). The isoscalar molecular state (Z) over tilde (c1) with 0(-)(1(+-)) can be searched for in the channel (Z) over tilde (c1)eta. Experimental discovery of these partner states will firmly establish the molecular picture.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000327092600003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, Particles & FieldsSCI(E)19ARTICLE11null7
Unveiling the Therapeutic Potential of Berberine in Rheumatoid Arthritis: A Comprehensive Study of Network Pharmacology, Metabolomics, and Intestinal Flora [Erratum]
Get PDFLi B, Liu J, He C, Deng Z, Zhou X, Peng R. J Inflamm Res. 2024;17:10849—10869.
The authors have advised the second listed corresponding author, Zhou Deng, is incorrect. The correct corresponding author is Xiaohong Zhou. The remaining details are correct.
This error was introduced by the Editorial staff during the publication process
Irpex subulatus Z. B. Liu & Y. C. Dai, comb. nov.
No full textIrpex subulatus (Ryvarden) Z.B. Liu & Y.C. Dai, comb. nov. (Fig. 4) MycoBank no.— MB 841368 Basionym: Oxyporus subulatus Ryvarden, Nordic Journal of Botany 2(3): 280 (1982). ≡ Flavodon subulatus (Ryvarden) F. Wu, Jia J. Chen & Y.C. Dai, Mycologia 109(5): 761 (2017). = Flavodon ambrosius D.R. Simmons, You Li, C.C. Bateman & J. Hulcr, Mycotaxon 131(2): 279 (2016). Holotype:— Thailand. Cangwat Lamphum, Doi Inthanond, 20 February 1979, Ryvarden 17843 Description: See Hjortstam & Ryvarden (1982, as Oxyporus subulatus). Specimens examined: CHINA. Henan Province, Xiuwu County, Yuntaishan, on fallen angiosperm trunk, 4 September 2009, B. K. Cui, Cui 7275 (BJFC 005762); Hubei Province, Shennongjia, Muyu, on fallen trunk of Celtis, 25 September 2004, Y. C. Dai, Dai 5929 (BJFC 010379, IFP 003711); Shanxi Province, Zhouzhi County, Taibaishan Nature Reserve, on fallen angiosperm trunk, 25 October 2006, H. S. Yuan, Yuan 2733 (BJFC 001406, IFP 003703); THAILAND. Chiang Mai, on fallen angiosperm trunk, 24 July 2016, Y. C. Dai, Dai 16719 (BJFC 022826). Notes: Simmons et al. (2016) described Flavodon ambrosius as a new species. In fact, we found that its description fits Oxyporus subulatus well, and its holotype (Hulcr 6853) sequences of ITS and LSU (ITS: KR 119072; LSU: KR 119075) are almost the same as those from Oxyporus subulatus. Wu et al. (2017) transferred Oxyporus subulatus to Flavodon based on the results of the phylogenetic analyses. Herein, we place this species in Irpex based on morphological and phylogenetic evidence (Fig. 1).Published as part of Tian, Xue-Mei, Man, Xiao-Wu & Liu, Zhan-Bo, 2022, Irpex jinshaensis sp. nov. and I. subulatus comb. nov. (Irpicaceae, Polyporales), evidenced by morphological characters and phylogenetic analysis, pp. 73-82 in Phytotaxa 533 (1) on pages 79-80, DOI: 10.11646/phytotaxa.533.1.4, http://zenodo.org/record/597413
Influence of ac ageing on space charge dynamics in LDPE
No full textPolymeric materials have been widely used as insulation in power industry due to their excellent electrical properties. However, these properties deteriorate in time irreversibly when the material is subjected to electric stress. Although space charge is believed to play an important role in ac ageing, exact mechanisms are poorly understood due to very limited experimental data. In the present work efforts have been made to investigate the influence of ac ageing on space charge dynamics in low-density polyethylene (LDPE). LDPE films with 200mm were aged at 50 kV/mm at 50 Hz for various times at ambient temperature. Space charge dynamics in the samples prior to and after ageing were monitored using the pulsed electroacoustic (PEA) technique under dc electric stress. The results indicate that there is a significant amount of homocharge accumulation in the unaged sample due to charge injection. These injected charges are the captured by the deep traps originated from the interface between crystalline and amorphous regions in LDPE. Ageing under ac condition does not necessarily lead to an increase in amount of charge in the bulk but leads to an increase in mobility of charge carriers. Chemical analysis by infrared spectroscope (FTIR) reveals there are chemical changes taken place in the bulk of the material after ac ageing. It is believed that the chemical changes introduce shallow traps which promote the movement of charge carriers in the bulk. Consequently, the injected charges spread across the sample
Cancellation of drift kinetic effects between thermal and energetic particles on the resistive wall mode stabilization
No full textDrift kinetic stabilization of the resistive wall mode (RWM) is computationally investigated using MHD-kinetic hybrid code MARS-K following the non-perturbative approach (Liu et al 2008 Phys. Plasmas 15 112503), for both reversed field pinch (RFP) and tokamak plasmas. Toroidal precessional drift resonance effects from trapped energetic ions (EIs) and various kinetic resonances between the mode and the guiding center drift motions of thermal particles are included into the self-consistent toroidal computations. The results show cancellation effects of the drift kinetic damping on the RWM between the thermal particles and EIs contributions, in both RFP and tokamak plasmas, even though each species alone can provide damping and stabilize RWM instability by respective kinetic resonances. The degree of cancellation generally depends on the EIs equilibrium distribution, the particle birth energy, as well as the toroidal flow speed of the plasma
The 2019 International Bamboo Construction Competition
No full textIn 2019, the International Bamboo and Rattan Organisation (INBAR) launched the International Bamboo Construction Competition 2019 (IBCC 2019). IBCC 2019 is an international contest aimed at university students of architecture, civil engineering, landscape, and other construction-related courses. The objective of the competition is to invite students to explore the potential construction applications for both bamboo poles and engineered bamboo products. IBCC 2019 was sponsored by several important companies working in the development of innovative bamboo products for the construction and design industries. The competition was organized on three different stages: pre-selection and qualification; selection of the three projects to be realized; and realization and award of the best project. This chapter opens with a discussion on the nature of the competition and then summarizes the key steps of the IBCC 2019 from the ideation to the award ceremony. The key design goals are widely discussed together with a deep analysis of the potentiality of bamboo for the construction industry
Dodecatwistarene Imides with Zigzag-Twisted Conformation for Organic Electronics
Get PDF1D nonplanar graphene nanoribbons generally have three possible conformers: helical, zigzag, and mixed conformations. Now, a kind of 1D nonplanar graphene nanoribbon, namely dodecatwistarene imides featuring twelve linearly fused benzene rings, was obtained by bottom-up synthesis of palladium-catalyzed Stille coupling and C−H activation. Single-crystal X-ray diffraction analyses revealed that it displays a zigzag-twisted conformation caused by steric hindrance between imide groups and neighboring annulated benzene rings with the pendulum angle of 53°. This conformation is very stable and could not convert into other conformations even when heated up to 250 °C for 6 h. Despite of the highly twisted topology, organic field-effect transistor based on it exhibits electron mobility up to 1.5 cm2 V−1 s−1 after annealing
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