Wei Zhang^1,2, Qihui Ling^1,2,*, Qiancheng Zhao^1,2, Hushu Wu³

Energy Engineering, Vol.118, No.5, pp. 1515-1535, 2021, DOI:10.32604/EE.2021.014162 - 16 July 2021

Abstract The condition monitoring and fault diagnosis have been identified as the key to achieving higher availabilities of wind turbines. Numerous studies show that the open-circuit fault is a significant contributor to the failures of wind turbine converter. However, the multiple faults combinations and the influence of wind speed changes abruptly, grid voltage sags and noise interference have brought great challenges to fault diagnosis. Accordingly, concerning the open-circuit fault of converters in direct-driven PMSG wind turbine, a diagnostic method for multiple open-circuit faults is proposed in this paper, which is divided into two tasks: The first… More >

Yilin Hu¹, Yan Xie², Bo Li^3,*, Yiqiang Jiang¹, Fu Bao¹

Energy Engineering, Vol.118, No.4, pp. 911-929, 2021, DOI:10.32604/EE.2021.014759 - 31 May 2021

Abstract Wind turbine employs pitch angle control to maintain captured power at its rated value when the wind speed is higher than rated value. This work adopts a perturbation observer based sliding-mode control (POSMC) strategy to realize robust variable-pitch control of permanent magnet synchronous generator (PMSG). POSMC combines system nonlinearities, parametric uncertainties, unmodelled dynamics, and time-varying external disturbances into a perturbation, which aims to estimate the perturbation via a perturbation observer without an accurate system model. Subsequently, sliding mode control (SMC) is designed to completely compensate perturbation estimation in real-time for the sake of achieving a More >

Jin Zhang¹, Youliang Tang¹, Feng Yu^2,*

Energy Engineering, Vol.118, No.4, pp. 1083-1094, 2021, DOI:10.32604/EE.2021.014482 - 31 May 2021

Abstract In this paper, position sensorless control system of permanent magnet synchronous linear motor (PMSLM) based on sliding mode observer (SMO) with an improved phase-locked loop (PLL) is studied. Firstly, according to the mathematical model, a SMO is designed for sensorless control PMSLM drive. Thereafter, an improved PLL is proposed to tackle the imperfection of data overflow existed in the traditional PLL. The designed SMO incorporating with the improved PLL can be effectively suppress the pulsation of the estimated position and hence the chattering of the derived electrical angular velocity. At last, simulated and experimental results More >

Xinglong Wang^1,2, Cheng Wang^1,2, Xin Zhou^1,*, Mingkang Zhang³, Peiyu Zhang¹, Lei Wang²

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.2, pp. 495-508, 2020, DOI:10.32604/cmes.2020.09778 - 01 May 2020

Abstract The new regenerative cooling thermal protection system exhibits the multifunctional characteristics of load-carrying and heat exchange cooling, which are fundamental for the lightweight design and thermal protection of hypersonic vehicles. Triply periodic minimal surface (TPMS) is especially suitable for the structural design of the internal cavity of regenerative cooling structures owing to its excellent structural characteristics. In this study, test pieces were manufactured using Ti6Al4V lightweight material. We designed three types of porous test pieces, and the interior was filled with a TPMS lattice (Gyroid, Primitive, I-WP) with a porosity of 30%. All porous test… More >

Hongbin Wang¹, Lianke Zhou¹, Guodong Zhao^1,*, Nianbin Wang¹, Jianguo Sun¹, Yue Zheng², Lei Chen³

CMC-Computers, Materials & Continua, Vol.59, No.1, pp. 229-237, 2019, DOI:10.32604/cmc.2019.04628

Abstract Borda sorting algorithm is a kind of improvement algorithm based on weighted position sorting algorithm, it is mainly suitable for the high duplication of search results, for the independent search results, the effect is not very good and the computing method of relative score in Borda sorting algorithm is according to the rule of the linear regressive, but position relationship cannot fully represent the correlation changes. aimed at this drawback, the new sorting algorithm is proposed in this paper, named PMS-Sorting algorithm, firstly the position score of the returned results is standardized processing, and the More >

Ting Liu¹, Fang Liu¹, Lei-Wen Peng, Li Chang, Yong-Mei Jiang

Oncology Research, Vol.26, No.5, pp. 817-826, 2018, DOI:10.3727/096504017X15130753659625

Abstract Peritoneal macrophages (PMs) are the major cell type of peritoneal cells that participate in multiple aspects of innate and acquired immunity in the peritoneal cavity. PMs have an ability to release a large amount of proinflammatory and anti-inflammatory cytokines and therefore play a critical role in regulating the differentiation of innate immune cells and inflammatory T cells. Accumulating studies demonstrate that the immunological reactions and inflammatory responses of PMs are strongly related to the pathogenic processes of various inflammatory diseases and abdominal cancers. Consequently, the regulation of PM activation has gradually emerged as a promising More >

M. Dumbser¹, D.S. Balsara²

CMES-Computer Modeling in Engineering & Sciences, Vol.54, No.3, pp. 301-334, 2009, DOI:10.3970/cmes.2009.054.301

Abstract In this article we use the new, unified framework of high order one-step P_NP_M schemes recently proposed for inviscid hyperbolic conservation laws by Dumbser, Balsara, Toro, and Munz (2008) in order to solve the viscous and resistive magnetohydrodynamics (MHD) equations in two and three space dimensions on unstructured triangular and tetrahedral meshes. The P_NP_M framework uses piecewise polynomials of degree N to represent data in each cell and piecewise polynomials of degree M ≥ N to compute the fluxes and source terms. This new general machinery contains usual high order finite volume schemes (N = 0) and discontinuous… More >

ELEONIDAS MOURA LIMA^1,2, MARIANA FERREIRA LEAL³, MARÍLIA DE ARRUDA CARDOSO SMITH³, ROMMEL RODRÍGUEZ BURBANO⁴, PAULO PIMENTEL DE ASSUMPÇÃO⁵, MARIA JOSE BELLO⁶, JUAN ANTONIO REY⁶, FRANCINALDO FERREIRA DE LIMA⁷, CACILDA CASARTELLI²

BIOCELL, Vol.32, No.3, pp. 237-243, 2008, DOI:10.32604/biocell.2008.32.237

Abstract Gastric cancer is one of the most common malignancies. DNA methylation is implicated in DNA mismatch repair genes deficiency. In the present study, we evaluated the methylation status of MLH1, MSH2, MSH6 and PMS2 in 20 diffuse- and 26 intestinal-type gastric cancer samples and 20 normal gastric mucosal of gastric cancer patients from Northern Brazil. We found that none of the nonneoplastic samples showed methylation of any gene promoter and 50% of gastric cancer samples showed at least one methylated gene promoter. Methylation frequencies of MLH1, MSH2, MSH6 and PMS2 promoter were 21.74%, 17.39%, 0% and 28.26% respectively… More >