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GA-BASED PID NEURAL NETWORK CONTROL FOR MAGNETIC BEARING SYSTEMS

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Chinese Journal of Mechanical Engineering 2007年第2期20卷 56-59页

作者： LI Guodong zhang qingchun LIANG Yingchun School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

In order to overcome the system non-linearity and uncertainty inherent in magnetic bearing systems, a GA（genetic algnrithm）-based PID neural network controller is designed and trained tO emulate the operation of a complete system （magnetic bearing, controller, and power amplifiers）. The feasibility of using a neural network to control nonlinear magnetic bearing systems with unknown dynamics is demonstrated. The key concept of the control scheme is to use GA to evaluate the candidate solutions （chromosomes）, increase the generalization ability of PID neural network and avoid suffering from the local minima problem in network learning due to the use of gradient descent learning method. The simulation results show that the proposed architecture provides well robust performance and better reinforcement learning capability in controlling magnetic bearing systems.

关键词： Magnetic bearing Non-linearity PID neural network Genetic algorithm Local minima Robust performance

A DAMAGE MECHANICS MODEL FOR FATIGUE LIFE PREDICTION OF FIBER REINFORCED POLYMER COMPOSITE LAMINA

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Acta Mechanica Solida Sinica 2011年第5期24卷 399-410页

作者： Wenjing Shi Weiping Hu Miao zhang qingchun Meng Institute of Solid Mechanics School of Aeronautics Science and Engineering BeiHang University Beijing 100191 China

A damage mechanics fatigue life prediction model for the fiber reinforced polymer lamina is established. The stiffness matrix of the lamina is derived by elastic constants of fiber and matrix. Two independent damage degrees of fiber and matrix are introduced to establish constitutive relations with damage. The damage driving forces and damage evolution equations for fiber and matrix are derived respectively. Fatigue tests on 0° and 90° unidirectional laminates are conducted respectively to identify parameters in damage evolution equations of fiber and matrix. The failure criterion of the lamina is presented. Finally, the life prediction model for lamina is proposed.

关键词： fiber reinforced polymer composite lamina continuum damage mechanics fatigue life prediction fiber breakage matrix cracking

Variations in nano-and pico-eukaryotic phytoplankton assemblages in the Qinhuangdao green-tide area

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Journal of Oceanology and Limnology 2022年第6期40卷 2446-2461页

作者： Weiqian zhang Hongbin HAN Limei QIU Chao LIU qingchun zhang Guizhong ZHOU Qingdao University of Science and Technology Qingdao 266071China CAS and Shandong Province Key Laboratory of Experimental Marine Biology Institute of OceanologyCAS Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China University of Chinese Academy of Sciences Beijing 100049China Center of Ocean Mega Science Chinese Academy of SciencesQingdao 266071China

Qinhuangdao coastal waters have been frequently hitting by nano-and pico-eukaryotic phytoplankton(NPEP)blooms and green tides(macroalgal blooms)in the recent ***,understanding about the impacts of environmental factors and the green tides on the NPEP assemblages in this area is *** this study,the composition of NPEP assemblages and their variations were analyzed via amplicon sequence variants(ASVs)assay based on amplicon high-throughput sequencing data with the 18S V4 region as a targeted gene in the Qinhuangdao green-tide area during the green ***,average NPEP effective sequences and ASVs of 178000 and 200 were obtained from each sample,*** there were 25 classes,110 genera,and 97 species of NPEP were identified and annotated,the proportions of annotated ASVs at genus and species levels were only 44.7%and 17.8%,*** NPEP communities had a seasonal succession from diatom-dominated to *** the three investigations,Skeletonema,Karlodinium,and Gonyaulax were the most dominant genera in May,August,and September,*** diversity and the abundance of NPEP communities could be increased by a high content of dissolved organic nitrogen(DON)and dissolved organic phosphorus(DOP)but inhibited by low dissolved inorganic phosphorus *** outbreak of green tides could alter the composition and content of nutrients and accelerate the succession of the NPEP communities from diatom-dominated to dinoflagellate-dominated under the background of a seasonal increase in seawater *** results preliminarily revealed the impacts of the recurrent occurrences of green tides on the NPEP assemblages in the Qinhuangdao green-tide area exhibiting high DON content and dissolved inorganic nitrogen/phosphorus ratio.

关键词： nano-and pico-eukaryotic phytoplankton high-throughput sequencing green tide eutrophication Qinhuangdao

Mapping the resting cysts of dinoflagellate Alexandrium catenella along the coast of Qinhuangdao,China

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Journal of Oceanology and Limnology 2022年第6期40卷 2312-2321页

作者： Wenjiao TANG Huixia GENG Yanjuan XI qingchun zhang Xuexi TANG Rencheng YU College of Marine Life Science Ocean University of ChinaQingdao 266003China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Hebei Academy of Ocean and Fishery Science Qinhuangdao 066200China

Dinoflagellate Alexandrium catenella is a cosmopolitan bloom-forming species with complex life cycle,the formation and germination of resting cysts are critical for its bloom *** the coastal waters of Qinhuangdao,*** has been identified as the major causative agent for paralytic shellfish poisoning,but there is little knowledge concerning its resting cysts in this *** this study,three surveys were carried out along the coast of Qinhuangdao from 2020 to 2021 to map the distribution of *** resting cysts,using a quantitative PCR(qPCR)assay specific for *** resting cysts were detected in surface sediments during all the three surveys,and their distribution patterns were *** abundance of resting cysts(maximum 1300 cysts/g sediment(wet weight))were found in a region(119.62°E-119.99°E,39.67°N-39.98°N)northeast to the coastal waters of Qinhuangdao,where surface sediments were mainly composed of clay and silt(percentage above 50%).Prior to the formation of the *** bloom in March 2021,the abundance of *** vegetative cells in seawater had extremely significant positive correlation with the abundance of resting cysts in surface sediments,reflecting the important role of resting cysts in the initiation of *** *** far as we know,this is the first report on the distribution of *** cysts along the coast of *** results will of fer a sound basis for the future monitoring and mitigation of toxic *** blooms and paralytic shellfish poisoning events in this region.

关键词： harmful algal bloom(HAB) Alexandrium catenella resting cyst paralytic shellfish toxin(PST) Qinhuangdao

Molecular Scrippsiella phylogenetic analysis of dinoflagellate trochoidea isolated from the East Asianwaters

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Chinese Journal of Oceanology and Limnology 2010年第2期28卷 323-328页

作者： TANG Xianghai YURencheng zhang qingchun WANG Yunfeng YAN Tian ZHOU Mingjiang Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Previous studies found intraspecific diversity in Scrippsiella trochoidea A. R. Loeblich Ill, a widely distributed calcareous cyst-producing dinoflagellate. In this study, three strains （ST-I, ST-D6 and ST-K） of S. trochoidea isolated from the East Asian waters were studied, together with other geographical strains, to resolve their phylogenetic relationships. For the three East Asian isolates, two highly diverse regions of nuclear-encoded ribosomal DNA （rDNA）, the 5.8S rDNA and its flanking internal transcribed spacers 1 and 2, and the 5＇ portion of the large-subunit rDNA （encompassing the ＂DI＂ and ＂D2＂ domains） were sequenced. Homologous sequences from other geographical isolates were selected from the GenBank database and the phylogenetic relationships were inferred from the molecular data of these strains. Strains of S. trochoidea were found to cluster into three major clades （STR1, STR2 and STR3）, as reported in previous studies. Two of the three strains ST-1 and ST-K, were grouped in clade STR2, the other strain, ST-D6, belonged to clade STR3. The intraspecific diversity ofS. trochoidea in East Asian waters makes it necessary to carry out phylogenetic investigations in combination with data of biogeography, population dynamics, and life cycle on the ecophysiology of a region.

关键词： Serippsiella trochoidea phylogeny rDNA molecular systematics

Insight into coupled Ni-Co dual-metal atom catalysts for efficient synergistic electrochemical CO_(2)reduction

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Journal of Energy Chemistry 2023年第12期87卷 509-517,I0013页

作者： qingchun zhang Di Liu Yaping zhang Zhiliang Guo Minpeng Chen Yuyun Chen Bo Jin Yingze Song Hui Pan State Key Laboratory of Environment-Friendly Energy Materials School of Materials and ChemistryTianfu Institute of Research and InnovationSouthwest University of Science and TechnologyMianyang 621010SichuanChina Institute of Applied Physics and Materials Engineering University of MacaoMacao 999078China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189JiangsuChina

The development of highly active,selective,and stable electrocatalysts can facilitate the effective implementation of electrocatalytic CO_(2)conversion into fuels or chemicals for mitigating the energy crisis and climate ***,it is necessary to achieve the goal through reasonable material design based on the actuality of the operational active site at the molecular *** by the stimulating synergistic effect of coupled heteronuclear metal atoms,a novel Ni-Co atomic pairs configuration(denoted as NiN_(3)?CoN_(3)-NC)active site was theoretically screened out for improving electrochemical CO_(2)reduction reaction(CO_(2)RR).The structure of NiN_(3)?CoN_(3)-NC was finely regulated by adjusting Zn content in the precursors Zn/Co/Ni-zeolite imidazolate frameworks(Zn/Co/Ni-ZIFs)and pyrolysis *** structural features of NiN_(3)?CoN_(3)-NC were systematically confirmed by aberration-corrected HAADF-STEM coupled with 3D atom-overlapping Gaussian-function fitting mapping,XAFS,and *** results of theoretical calculations reveal that the synergistic effect of Ni-Co atomic pairs can effectively promote the*COOH intermediate formation and thus the overall CO_(2)RR kinetic was improved,and also restrained the competitive hydrogen evolution *** to the attributes of Ni-Co atomic pairs configuration,the developed NiN_(3)?CoN_(3)-NC with superior catalytic activity,selectivity,and durability,with a high turnover frequency of 2265 h^(-1)at-1.1 V(***)and maximum Faradaic efficiency of 97.7%for CO *** work demonstrates the great potential of DACs as highly efficient catalysts for CO_(2)RR,provides a useful strategy to design heteronuclear DACs,exploits the synergistic effect of multiple metal sites to facilitate complex CO_(2)RR catalytic reactions,and inspires more efforts to develop the potential of DACs in various fields.

关键词： Coupled dual-metal atom catalysts CO_(2)reduction reaction Electrocatalysts Density functional theory

Tracing the settlement region of massive floating green algae in the Yellow Sea

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Journal of Oceanology and Limnology 2019年第5期37卷 1555-1565页

作者： GENG Huixia YU Rencheng zhang qingchun YAN Tian KONG Fanzhou ZHOU Mingjiang Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology (Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Outbreaks of large-scale green tides formed by Ulva prolifera in the Yellow Sea (YS) cause heavy ecological damages and huge economic losses. However, the ecological consequences of green tides remain poorly understood due to the lack of knowledge on the settlement region of massive green algae floating in the YS. In this study, we established a method to trace the settlement region of floating green algae, using 28-isofucosterol preserved in sediment as the specific biomarker for green algae. Sterols including 28-isofucosterol in surface sediment samples collected during an investigation in the YS and the Bohai Sea (BS) in August 2015 were analyzed using gas chromatography coupled with a mass spectrometer (GC-MS). Based on the content of 28-isofucosterol in sediment samples, the potential settlement region of fl oating green algae was identifi ed in the sea area southeast to the Shandong Peninsula around the sampling site H06 (122.66°E, 36.00°N). This paper presents a first result on the settlement region of floating green algae in the YS for providing a solid basis to elucidate the ecological consequences of green tides in the area.

关键词： green tide biomarker sterol Ulva prolifera

Screening for lipophilic marine toxins and their potential producers in coastal waters of Weihai in autumn,2020

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Journal of Oceanology and Limnology 2022年第6期40卷 2218-2230页

作者： Huixia GENG Hongxiao SUN Chao LIU Fanzhou KONG qingchun zhang Tian YAN Rencheng YU CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Lipophilic marine toxins(LMTs)produced by some microalgae in the sea could accumulate in shellfish and pose potential threats to the health of seafood *** and shellfish samples were collected from coastal waters of Weihai in Shandong Peninsula,China in autumn,2020,and screened for lipophilic marine toxins and their potential producers using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis and high throughput sequencing of partial DNA(V4 region of the 18S rRNA gene)extracted from ***-2(PTX2),trace amounts of azaspiracid(AZA1 or AZA40),and 13-desmethyl spirolide C(13-DesMe-C)were detected in phytoplankton samples,while PTX2 and gymnodimine(GYM)were detected in shellfish *** toxin content in shellfish samples was much lower than the regulatory limit or values reported *** suggest that lipophilic marine toxins should have low risk in coastal waters of Weihai in *** on the data of high throughput sequencing,the OTUs were assigned to 5 identified species of Alexandrium,including *** capable of producing 13-DesMe-C and *** OTUs were found closely related to the toxic species in genus Dinophysis,but it is impossible to assign them to any identified species due to the low resolving power of the V4 region for *** OTUs could not be assigned to any identified species in the genus Azadinium,suggesting the existence of unidentified species in this region.

关键词： harmful algal blooms phytoplankton shellfish lipophilic marine toxins(LMTs) Yellow Sea liquid chromatography-tandem mass spectrometry

Development of high-resolution chloroplast markers for intraspecific phylogeographic studies of Phaeocystis globosa

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Journal of Oceanology and Limnology 2021年第2期39卷 508-524页

作者： qingchun zhang Zhuang NIU Jinxiu WANG Chao LIU Fanzhou KONG Xiaokun HU Jiayu ZHAO Rencheng YU CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Sciences Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center of Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Phaeocystis globosa is an important harmful algal bloom causative species distributing widely in temperate and tropical coastal waters in the *** morphological,physiological,and biochemical characteristics are different among geographic strains,which can not be distinguished with nuclear ribosomal DNA markers at ***,the genetic distance and phylogeographic relationships of nuclear 28S rDNA D1–D2 and ITS regions,and three chloroplast intergenic spacers(petN-trnS1,trnM1-psbA,and rbcS-rpl27)were analyzed and compared among 13 strains of *** isolated from the Pacific Ocean and Atlantic Ocean in this *** addition,the nucleotide polymorphisms of 28S rDNA D1–D2,ITS,and rbcS-rpl27 regions were evaluated in two *** *** various levels of nucleotide polymorphism were in the nuclear 28S rDNA D1–D2 region and ITS region,but no polymorphism was in the chloroplast rbcS-rpl27 intergenic spacer.A reasonable intraspecific phylogeographic relationship was presented by rbcS-rpl27 intergenic spacer,which had the strongest distinction to geographic strains compared to those of 28S rDNA D1–D2 and ITS *** the phylogenetic tree of rbcS-rpl27 intergenic spacer,the two strains from the North Sea of the Atlantic Ocean were divided firstly from the species of ***,and then formed an independent clade,while the other Atlantic strains and all of Pacific strains joined up to build the other *** was implied that at least two genetically distant populations of *** existed in the Atlantic coastal *** study provided a high-resolution chloroplast marker to analyze intraspecific phylogeographic populations of ***,and preliminarily clarified the genetic relationships of the Pacific and Atlantic strains of ***.

关键词： Phaeocystis globosa chloroplast DNA marker phylogeny