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Adaptive Coordinated Control for Hot Strip Finishing Mills

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Journal of Iron and Steel Research International 2011年第4期18卷 36-43页

作者： JIAO Xiao-hong shao Li-ping PENG yan Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 Hebei China Institute of Mechanical Engineering Yanshan University Qinhuangclao 066004 Hebei China

To further improve the control accuracy for strip dimension of hot strip mills,an adaptive control scheme is investigated for a hot strip finishing mill based on the decentralization and coordination among the controllers of gauge,tension and ***,the adaptive controller designed can regulate simultaneously the strip exit thickness,the strip tension and the looper angle to ensure better performance of the strip quality of finishing ***,the control scheme is proposed in consideration of the essential nonlinearity and the unavoidable friction phenomena in the mechanical system,so the controller can be efficient in a wider range of working *** simulation results of a model obtained from a real hot strip finishing mill show the effectiveness of the proposed control scheme in comparison with the conventional control method.

关键词： hot strip finishing mills exist gauge tension looper angle adaptive control

Impact Analysis of Solar Irradiance Change on Precision Orbit Determination of Navigation Satellites

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第6期36卷 889-901页

作者： ZHANG yan WANG Xiaoya XI Kewei shao Fan Astro-Geodynamics Research Center Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030P.R.China

Solar radiation pressure is the main driving force and error source for precision orbit determination of navigation *** is proportional to the solar irradiance,which is the"sun constant".In regular calculation,the"solar constant"is regard as a ***,due to the existence of sunspots,flares,etc.,the solar constant is not fixed,the change in the year is about 1%.To investigate the variation of solar irradiance,we use interpolation and average segment modeling of total solar irradiance data of SORCE,establishing variance solar radiation pressure(VARSRP)model and average solar radiation pressure(AVESRP)model based on the built solar pressure model(SRPM)(constant model).According to observation data of global positioning system(GPS)and Beidou system(BDS)in 2015 and comparing the solar pressure acceleration of VARSRP,AVESRP and SRPM,the magnitude of change can reach 10-10 m/s^*** addition,according to the satellite precise orbit determination,for GPS satellites,the results of VARSRP and AVESRP are slightly smaller than those of the SRPM model,and the improvement is between 0.1 to 0.5 *** geosynchronous orbit(GEO)satellites of BDS,The AVESRP and VARSRP have an improvement of 3.5 mm and 4.0 mm,respectively,based on overlapping arc,and SLR check results show the AVESRP model and the VARSRP model is improved by 2.3 mm and 3.5 mm,***,the change of inclined geosynchronous orbit(IGSO)satellites and medium earth orbit(MEO)satellites is relatively small,and the improvement is smaller than 0.5 mm.

关键词： solar pressure acceleration total solar irradiance precise orbit determination global positioning system(GPS) Beidou system(BDS)

Modeling ε Eri and Asteroseismic Tests of Element Diffusion

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 591-602页

作者： Ning Gai shao-Lan Bi yan-Ke Tang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Department of Astronomy Beijing Normal University Beijing 100875 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Taking into account the helium and metal diffusion, we explore the possible evolutionary status with a seismic analysis, of the MOST （Microvariability and Oscillations of STars） target： the star e Eri. We adopt different input parameters to construct models to fit the available observational constraints in, e.g., Teff, L, R and [Fe/H]. From the computation we obtain the average large spacings of e Eri to be about 194 ± 1μHz. The age of the diffused models was found to be about 1 Gyr, which is younger than the age determined previously by models without diffusion. We found that the effect of pure helium diffusion on the internal structure of the young low-mass star is slight, but that of metal diffusion is obvious. The metal diffusion leads the models to have much higher temperature in the radiative interior, and, correspondingly a higher sound speed there, hence a larger frequency and spacings.

关键词： stars evolution - stars interiors -stars individual ∈ Eridani

The current application of thermal ablation in colorectal liver metastasis

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Hepatobiliary Surgery and Nutrition 2021年第6期10卷 872-874页

作者： Zhongyi Zhang kun yan Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of UltrasonographyPeking University Cancer Hospital&InstituteBeijingChina

Colorectal liver metastases(CRLM)are one of the most frequent clinical *** the last 20 years,the clinical outcome for patients with CRLM has improved *** resection is the gold standard treatment for resectable CRLM,achieving a 5-year overall survival(OS)rate of 42%(1).However,the majority of patients with CRLM are not candidates for *** the development of thermal ablation,this technique provides an alternative treatment modality by either ablation alone or combined with resection.A recent review by Takahashi et *** the current role of thermal ablation in the management of CRLM(2).

关键词： clinical metastasis Liver

Temporal and spatial changes in nutrients and chlorophyll-a in a shallow lake,Lake Chaohu, China: An 11-year investigation

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Journal of Environmental Sciences 2013年第6期25卷 1117-1123页

作者： Libiao yang kun Lei Wei Meng Guo Fu Weijin yan River and Coastal Environment Research Center Chinese Research Academy of Environmental Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Temporal and spatial changes of total nitrogen （TN）, total phosphorus （TP） and chlorophyll-a （Chl-a） in a shallow lake, Lake Chaohu, China, were investigated using monthly monitoring data from 2001 through 2011. The results showed that the annual mean concentration ranges of TN, TP, and Chl-a were 0.08-14.60 mg/L, 0.02-1.08 mg/L, and 0.10-465.90 ~tg/L, respectively. Our data showed that Lake Chaohu was highly eutrophic and that water quality showed no substantial improvement during 2001 through 2011. The mean concentrations of TP, TN and Chl-a in the western lake were significantly higher than in the eastern lake, which indicates a spatial distribution of the three water parameters. The annual mean ratio of TN：TP by weight ranged from 10 to 20, indicating that phosphorus was the limiting nutrient in this lake. A similar seasonality variation for TP and Chl-a was observed. Riverine TP and NH4＋ loading from eight major tributaries were in the range of 1.56× 10^4-5.47 × 10^4 and 0.19 × 104-0.51 × 10^4 tons/yr over 2002-2011, respectively, and exceeded the water environmental capability of the two nutrients in the lake by a factor of 3-6. Thus reduction of nutrient loading in the sub-watershed and tributaries would be essential for the restoration of Lake Chaohu.

关键词： eutrophication Lake Chaohu nitrogen phosphorus

SN 1054: A pulsar-powered supernova?

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Research in Astronomy and Astrophysics 2015年第11期15卷 1823-1831页

作者： shao-Ze Li Yun-Wei Yu yan Huang Institute of Astrophysics Central China Normal University

The famous ancient supernova SN 1054 could have been too bright to be explained in the “standard” radioactive-powered supernova scenario. As an alternative attempt, we demonstrate that the spin-down of the newly born Crab pulsar could provide a sufficient energy supply to make SN 1054 visible at daytime for 23 days and at night for 653 days, where a one-zone semi-analytical model is employed. Our results indicate that SN 1054 could be a “normal” cousin of magnetar-powered superluminous supernovae. Therefore, SN 1054-like supernovae could be a probe to uncover the properties of newly born neutron stars, which provide initial conditions for studies on neutron star evolutions.

关键词： scenario powered neutron gamma bright ancient luminosity attempt radioactive stars

Atmospheric-pressure pulsed discharges and plasmas:mechanism,characteristics and applications

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High Voltage 2018年第1期3卷 14-20页

作者： Tao shao Ruixue Wang Cheng Zhang Ping yan Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190People's Republic of China Key Laboratory of Power Electronics and Electric Drive Chinese Academy of SciencesBeijing 100190People's Republic of China

Pulsed discharge plasma and its application is one of the promising directions in civilian areas of pulsed power *** order to promote the research and development of the theory and application technology for pulsed discharge plasma,in this paper,recent progress on the mechanism of nanosecond-pulse gas discharge and the characteristics and applications of typical pulsed plasma at the Institute of Electrical Engineering,Chinese Academy of Sciences is ***,progress on mechanism of nanosecond-pulse discharge based on runaway electrons and measurement technology of runaway electrons is ***,the characteristics of three typical discharges,including direct-driven pulsed discharge,pulsed dielectric barrier discharge and pulsed plasma jet,are ***,typical plasma applications of pulsed plasma on surface modification and methane conversion are presented.

关键词： mechanism pulsed directions

Genetic dissection of hexanol content in soybean seed through genome-wide association analysis

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Journal of Integrative Agriculture 2019年第6期18卷 1222-1229页

作者： XIA Ning yan Wen-bing WANG Xiao-qi shao Yu-peng yanG Ming-ming WANG Zhi-kun ZHAN Yu-hang TENG Wei-li HAN Ying-peng SHI yan-guo Key Laboratory of Soybean Biology Ministry of Education/Key Laboratory of Soybean Biology and Breeding/GeneticsMinistry of Agriculture and Rural Affairs/Agricultural CollegeNortheast Agricultural UniversityHarbin 150030P.R.China School of Food Engineering Harbin University of CommerceHarbin 150030P.R.China

Hexanol is a major compound contributing to the off-flavors(the bean-like odor)of soybean derived *** most effective way to reduce the off-flavors of soymilk is the screening and utilization of soybean cultivars with improved hexanol ***,no genome-wide genetic analysis for this particular trait has been conducted to *** objective of the present study was to dissect the genetic basis of hexanol content in soybean seed through genome-wide association analysis(GWAS).A total of 105 soybean accessions were analyzed for hexanol content in a three-year experiments and genotyped by sequencing using the specific locus amplified fragment sequencing(SLAF-seq)approach.A total of 25 724 single nucleotide polymorphisms(SNPs)were obtained with minor allele frequencies(MAF)>5%.GWAS showed that 25 quantitative trait nucleotides(QTNs)were significantly associated with the hexanol concentration in soybean *** identified QTNs distributed on different genomic regions of the 15 chromosomes.A total of 91 genes were predicted as candidate genes underlying the seed hexanol level and six candidates were predicted possibly underlying the seed hexanol by gene based *** this study,GWAS has been proven to be an effective way to dissect the genetic basis of the hexanol concentration in multiple genetic *** identified beneficial alleles and candidate genes might be valuable for the improvement of marker-assisted breeding efficiency for low hexanol level and help to explore possible molecular mechanisms underlying hexanol content in soybean seed.

关键词： genome-wide association mapping soybean hexanol concentration candidate genes

Accessibility and Homology Bounded Strong Unstable Foliation for Anosov Diffeomorphisms on 3-torus

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Acta Mathematica Sinica,English Series 2017年第1期33卷 71-76页

作者： yan REN shao Bo GAN Peng Fei ZHANG School of Mathematical Sciences Peking University Department of Mathematics and Statistics Universityof Massachusetts

We give three equivalent conditions for non-accessibility of an Anosov diffeomorphism on the 3-torus with a partially hyperbolic splitting. Since accessibility is an open property, this gives a negative answer to Hammerlindl＇s question about homology boundedness of strong unstable foliation. Keywords Partially hyperbolic, accessible, homology bounded

关键词： Partially hyperbolic accessible homology bounded