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Active Disturbance Rejection Position Servo Control of PMSLM Based on Reduced-order Extended State Observer

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Chinese Journal of Electrical Engineering 2020年第2期6卷 30-41页

作者： Ming Li Jiwen Zhao Yuepeng hu Zhen Wang School of Electrical Engineering and Automation Anhui UniversityHefei 230601China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

To enhance the control accuracy of permanent magnet synchronous linear motor(PMSLM)servo systems affected by disturbances,such as time-varying parameters and abrupt load changes,an active disturbance rejection control(ADRC)algorithm based on a reduced-order extended state observer(ESO)is adopted to suppress the disturbances on the control ***,the system’s ability to estimate disturbances is enhanced by linearizing the ***,the pole placement method is used for the construction of a reduced-order ESO that can reduce the influence of the number of adjustment parameters and the phase *** parameters of the reduced-order ADRC are adjusted,the optimal control parameters are selected,and the stability of controller is ***,practical experiments prove that the proposed method can improve control accuracy under multiple working conditions and features strong anti-interference *** is a smaller steady-state error,and no overshoot is observed.

关键词： PMSLM ADRC reduced-order ESO anti-interface

The nature of the γ-ray flare associated with blazar 3C 454.3

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Research in Astronomy and Astrophysics 2015年第9期15卷 1455-1466页

作者： Wen hu Zhong-hui Fan Ben-Zhong Da Department of Astronomy Yunnan University Key Laboratory of Astroparticle Physics Yunnan Province

We have studied the simultaneous spectral energy distributions （SEDs） of the 2009 December flare and those of the quiescent state of blazar 3C 454.3 by con- structing a multi-component model We find that all six SEDs can be explained by a one-zone leptonic model involving synchrotron self-Compton （SSC） plus external Compton emission from an accretion disk （ECD） and that from a broad-line region （ECC）. X-ray emission is dominated by the SSC mechanism, and the γ-ray spectrum is well represented by a combination of ECD and ECC processes. Our results indicate that the energy density of the magnetic field and electrons decrease with distance from the central engine, and the Doppler factor increases with the blob moving outward in the development of the 2009 December flare. The increase in the observed flux density is possibly due to the increase in the Doppler factor of the blob. The relation between the Doppler factor σb and the distance from the central black hole suggests the magnetically driven jets span a sub-pc scale, and the relation between the magnetic field Bt and the dimension of the emission region R＇b is in good agreement with what is required by conservation of magnetic flux. The weak ＂harder-when-brighter＂ behavior of the γ-ray spectrum could be a result of the increase in Doppler factor during the outward motion of the blob. The parameters during the quiescent state obviously deviate from those during the flare state. We propose that the flare was likely caused by the ejection of a new blob. The gamma-ray emissions in different states are associated with the evolution of the blob.

关键词： radiation mechanisms: non-thermal -- methods: numerical -- galaxies:active -- quasars: individual (3C 454.3)

Characterization of a collection of Chinese fir elite genotypes using *** amplified polymorphism markers

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Journal of Forestry Research 2016年第5期27卷 1105-1110页

作者： Hongjing Duan Dehuo hu Yun Li huiquan Zheng National Engineering Laboratory for Tree Breeding Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of Education College of Biological Sciences and Technology Beijing Forestry University Beijing 100083 People's Republic of China Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest Guangdong Academy of ForestryGuangzhou 510520 People's Republic of China

Chinese fir [Cunninghamia lanceolata （Lamb.） Hook] is a major timber tree species in China. In the pre- sent study, sequence-related amplified polymorphism （SRAP） markers were used to evaluate the polymorphisms, diversity, and relationships in a collection of Chinese fir elite genotypes （n = 103） from the Lechang provenance, an endangered provenance. Thirty-five SRAP primer combinations produced 620 bands among the tested 103 Lechang provenance genotypes and 17 nonSLechang provenance genotypes; 577 （93.1%） of these were polymorphic, yielding an average of 16.5 polymorphic bands per primer combination. Of the SRAP primer combinations （n = 35）, I4 ones identified 〉70.0 % of the 120 genotypes. The Mel2-Eml9 combination had the strongest discriminatory ability with 93.3 % of the genotypes iden- tified. An UPGMA dendrogram further showed that most of the Lechang provenance genotypes （87.4 %） grouped together （Cluster A）. The Lechang genotypes had a con- siderable amount of genetic variation with genetic simi- larity from 0.40 to 0.81. The current work may facilitate the management of the endangered Lechang Chinese fir provenance.

关键词： Chinese fir SRAP Germplasm Geneticvariation - Dendrogram

QoE based power control scheme for interference mitigation in high-density WLANs

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The Journal of China Universities of Posts and Telecommunications 2016年第2期23卷 24-30页

作者： Wang Yiqing Wen Xiangming hu Zhiqun Lu Zhaoming School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Mobile data traffic is going through an explosive growth recently as mobile smart devices become more and more ubiquitous, causing huge pressure on cellular network. Taking advantage of its low cost and easy-to-deploy feature, wireless local-area networks（WLAN） becomes increasingly popular to offload data streams from cellular network, followed by higher and higher density of its deployment. However, the high density of WLAN will cause more interference, which results in degradation of its performance. Therefore, in order to enhance the performance of the network, we aim to minimize the interference caused by high density of WLAN. In this paper, we propose a novel power control scheme to achieve the above aim. We use the quality of experience（QoE） evaluation to coordinate the power of each access point（AP） and finally realize the optimization of the entire network. According to the simulation results, our scheme improves the performance of the network significantly in many aspects, including throughput and QoE.

关键词： power control high-density WLAN interference mitigation QoE

A Prediction-Based Multi-Objective VM Consolidation Approach for Cloud Data Centers

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Computers, Materials & Continua 2024年第7期80卷 1601-1631页

作者： Xialin Liu Junsheng Wu Lijun Chen Jiyuan hu School of Computer Science Northwestern Polytechnical UniversityXi’an710005China School of Computer Science and Technology Xi’an University of Posts and TelecommunicationsXi’an710021China Shaanxi Key Laboratory of Network Data Analysis and Intelligent Processing Xi’an University of Posts and TelecommunicationsXi’an710021China School of Software and Microelectronics Northwestern Polytechnical UniversityXi’an710005China School of Automation Xi’an University of Posts and TelecommunicationsXi’an710021China

Virtual machine(VM)consolidation aims to run VMs on the least number of physical machines(PMs).The optimal consolidation significantly reduces energy consumption(EC),quality of service(QoS)in applications,and resource *** paper proposes a prediction-basedmulti-objective VMconsolidation approach to search for the best mapping between VMs and PMs with good timeliness and practical *** use a hybrid model based on Auto-Regressive Integrated Moving Average(ARIMA)and Support Vector Regression(SVR)(HPAS)as a prediction model and consolidate VMs to PMs based on prediction results by HPAS,aiming at minimizing the total EC,performance degradation(PD),migration cost(MC)and resource wastage(RW)*** results usingMicrosoft Azure trace show the proposed approach has better prediction accuracy and overcomes the multi-objective consolidation approach without prediction(i.e.,Non-dominated sorting genetic algorithm 2,Nsga2)and the renowned Overload Host Detection(OHD)approaches without prediction,such as Linear Regression(LR),Median Absolute Deviation(MAD)and Inter-Quartile Range(IQR).

关键词： VM consolidation prediction multi-objective optimization machine learning

Complete convergence for arrays of rowwise negatively superadditive-dependent random variables and its applications

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Applied Mathematics(A Journal of Chinese Universities) 2016年第4期31卷 439-457页

作者： WU Yi WANG Xue-jun hu Shu-he School of Mathematical Sciences Anhui University

In this paper, an exponential inequality for the maximal partial sums of negatively superadditive-dependent （NSD, in short） random variables is established. By uSing the exponen- tial inequality, we present some general results on the complete convergence for arrays of rowwise NSD random variables, which improve or generalize the corresponding ones of Wang et al. [28] and Chen et al. [2]. In addition, some sufficient conditions to prove the complete convergence are provided. As an application of the complete convergence that we established, we further investigate the complete consistency and convergence rate of the estimator in a nonparametric regression model based on NSD errors.

关键词： exponential inequality, complete convergence, negatively superadditive-dependent random vari-ables nonparametric regression model, complete consistency.

Chromosomal Localization of the 5S and 45S rDNA Sites and 5S rDNA Sequence Analysis in Nelumbo Species

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Agricultural Sciences in China 2011年第5期10卷 679-685页

作者： DIAO Ying ZHOU Ming-quan hu Zhong-li College of Life Science and Technology Chongqing University of Arts and Sciences Yongchuan 402168 P.R. China Key Lab of Plant Developmental Biology Ministry of Education/Wuhan University Wuhan 430072 P.R.China

The physical location of 45S and 5S rDNA sites by double-target fluorescence in situ hybridization （FISH） and 5S rDNA non-transcribed spacer （NTS） sequences was studied in five accessions of Nelumbo nucifera *** one accession of *** *** （Willd.）.The chromosome number of all tested materials was 2n=*** loci of 5S rDNA were close to the centromere regions of chromosome 3,and the loci of 45S rDNA were found on chromosomes 7 and 8 in all the six tested accessions,***,45S rDNAs were also located on chromosome 4 in four tested *** 5S rRNA gene sequences were conserved and the NTS sequences were variable among the *** *** was the longest branch in the phylogenetic tree and clustered with *** *** *** and *** *** showed a close relationship with each *** *** Lian was closer to *** *** Lian than to other tested *** of the molecular karyotype and the 5S rRNA gene spacer sequence suggested the genetic diversity was limited within Nelumbo species and it seems suitable that American lotus was considered as the subspecies of ***.

关键词： Nelumbo chromosome 45S rDNA 5S rDNA NTS

A capability matching and ontology reasoning method for high precision OGC web service discovery

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International Journal of Digital Earth 2011年第6期4卷 449-470页

作者： Nengcheng Chen Zeqiang Chen Chuli hu Liping Di State Key Lab for Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China Center for Spatial Information Science and Systems George Mason UniversityFairfaxVA 22032USA

Finding the right spatially aware web service in a heterogeneous distributed environment using criteria such as service type,version,time,space,and scale has become a challenge in the integration of geospatial information services.A new method for retrieving Open Geospatial Consortium(OGC)Web Service(OWS)that deals with this challenge using page crawling,link detection,service capability matching,and ontology reasoning,is described in this *** major components are distributed OWS,the OWS search engine,the OWS ontology generator,the ontology-based OWS catalog service,and the ontology-based multi-protocol OWS *** results show that the execution time of this proposed method equals only 0.26 of that of Nutch’s *** addition,the precision is much ***,this proposed method can carry out complex OWS reasoning-based *** is being used successfully for the Antarctica multi-protocol OWS portal of the Geo-Information Web Service Portal of the Polar.

关键词： geospatial information service link detection capability matching OWL-S ontology reasoning

Risk measures with comonotonic subadditivity or convexity on product spaces

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 407-417页

作者： WEI Lin-xiao MA Yue hu Yi-jun College of Science Wuhan University of Technology School of Mathematics and Information Sciences North China University of Water Resources and Electric Power School of Mathematics and Statistics Wuhan University

In this paper, by an axiomatic approach, we propose the concepts of comonotonic subadditivity and comonotonic convex risk measures for portfolios, which are extensions of the ones introduced by Song and Yan （2006）. Representation results for these new introduced risk measures for portfolios are given in terms of Choquet integrals. Links of these newly introduced risk measures to multi-period comonotonic risk measures are represented. Finally, applications of the newly introduced comonotonic coherent risk measures to capital allocations are provided.

关键词： Choquet integral comonotonic subadditivity risk measure comonotonic convex risk measure,multi-period risk measure capital allocation product space.