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A Levenberg–Marquardt Method for Solving the Tensor Split Feasibility Problem

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Journal of the Operations Research Society of China 2021年第4期9卷 797-817页

作者： Yu-Xuan jin jin-Ling zhao School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

This paper considers the tensor split feasibility *** C and Q be non-empty closed convex set and A be a semi-symmetric *** tensor split feasibility problem is to find x∈C such that Axm−1∈*** we simply take this problem as a special case of the nonlinear split feasibility problem,then we can directly get a projection method to solve ***,applying this kind of projection method to solve the tensor split feasibility problem is not so *** we propose a Levenberg–Marquardt method to achieve higher *** analyses are conducted,and some preliminary numerical results show that the Levenberg–Marquardt method has advantage over the common projection method.

关键词： Tensor Split feasibility problem Semi-symmetric Projection Levenberg-Marquardt method

A multicolor photometric study of the neglected eclipsing binary FT Ursae Majoris

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Research in Astronomy and Astrophysics 2011年第10期11卷 1158-1162页

作者： jin-zhao Yuan Department of Physics Shanxi Normal University Linfen 041004 China

The multicolor photometric observations of the neglected eclipsing binary FT Ursae Majoris （FT UMa） were obtained in 2010. The 2003 version of the Wilson- Devinney code was used to analyze the light curves in the B, V and R bands simultaneously. Based on the spectroscopic mass ratio q = 0.984 published by Pribulla et al., it is found that FT UMa is an evolved contact binary with a contact degree of 15.3%. The low amplitude of light variations, N 0.15 mag, arises mainly from a moderately low inclination angle of i = 62.80° and almost identical components in size rather than the light dilution of a third component, which contributes light of only - 10%.

关键词： stars binaries close -- stars binaries clipsing -- stars individual FTUrsae Majoris

Average Amount and Stability of Available Agro-Climate Resources in the Main Maize Cropping Regions in China during 1981–2010

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Journal of Meteorological Research 2018年第1期32卷 146-156页

作者： jin zhao Xiaoguang YANG College of Resources and Environmental Sciences China Agricultural University

The available agro-climate resources that can be absorbed and converted into dry matter could directly affect crop growth and yield under climate change. Knowledge of the average amount and stability of available agro-climate resources for maize in the main cropping regions of China under climate change is essential for farmers and advisors to optimize cropping choices and develop adaptation strategies under limited resources. In this study, the three main maize cropping regions in China—the North China spring maize region（NCS）, the Huanghuaihai summer maize region（HS）, and the Southwest China mountain maize region（SCM）—were selected as study regions. Based on observed solar radiation, temperature, and precipitation data, we analyzed the spatial distributions and temporal trends in the available agro-climate resources for maize during 1981-2010. During this period, significantly prolonged climatological growing seasons for maize [3.3, 2.0, and 4.7 day（10 yr）^-1 in NCS, HS, and SCM] were found in all three regions. However, the spatiotemporal patterns of the available agro-climate resources differed among the three regions. The available heating resources for maize increased significantly in the three regions, and the rates of increase were higher in NCS [95.5℃ day（10 yr）^-1] and SCM [93.5℃ day（10 yr）^-1] than that in HS [57.7℃ day（10 yr）^-1].Meanwhile, decreasing trends in the available water resources were found in NCS [–5.3 mm（10 yr）^-1] and SCM[–5.8 mm（10 yr）^-1], whereas an increasing trend was observed in HS [3.0 mm（10 yr）^-1]. Increasing trends in the available radiation resources were found in NCS [20.9 MJ m^-2（10 yr）^-1] and SCM [25.2 MJ m^-2（10 yr）^-1], whereas a decreasing trend was found in HS [11.6 MJ m^-2（10 yr）^-1]. Compared with 1981–90, the stability of all three resource types decreased during 1991–2000 and 2001–10 in the three regions. More consideration should be placed on the extreme events caused by more intense climate fluctuations. The results

关键词： maize available agro-climate resources stability variability

Estimation of Vehicle Pose and Position with Monocular Camera at Urban Road Intersections

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Journal of Computer Science & Technology 2017年第6期32卷 1150-1161页

作者： jin-zhao Yuan Hui Chen Bin zhao Yanyan Xu School of Information Science and Engineering Shandong University Jinan 250100 China Beijing Xuanlongding-xun Technology Co. Ltd. Beijing 100041 China Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge 02139 U.S.A.

With the rapid development of urban, the scale of the city is expanding day by day. The road environment is becoming more and more complicated. The vehicle ego-localization in complex road environment puts forward imperative requirements for intelligent driving technology. The reliable vehicle ego-localization, including the lane recognition and the vehicle position and attitude estimation, at the complex traffic intersection is significant for the intelligent driving of the vehicle. In this article, we focus on the complex road environment of the city, and propose a pose and position estimation method based on the road sign using only a monocular camera and a common GPS （global positioning system）. Associated with the multi-sensor cascade system, this method can be a stable and reliable alternative when the precision of multi-sensor cascade system decreases. The experimental results show that, within 100 meters distance to the road signs, the pose error is less than 2 degrees, and the position error is less than one meter, which can reach the lane-level positioning accuracy. Through the comparison with the Beidou high-precision positioning system L202, our method is more accurate for detecting which lane the vehicle is driving on.

关键词： vehicle pose and position estimation road sign detection homograph matrix road intersection urban envi-ronment

PSG： a two-layer graph model for document summarization

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Frontiers of Computer Science 2014年第1期8卷 119-130页

作者： Heng CHEN Hai jin Feng zhao Service Computing Technology and System Lab & Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Graph model has been widely applied in docu- ment summarization by using sentence as the graph node, and the similarity between sentences as the edge. In this paper, a novel graph model for document summarization is presented, that not only sentences relevance but also phrases relevance information included in sentences are utilized. In a word, we construct a phrase-sentence two-layer graph structure model （PSG） to summarize document（s） . We use this model for generic document summarization and query-focused sum- marization. The experimental results show that our model greatly outperforms existing work.

关键词： relationship graph Markov random walk doc-ument summarization

BLOCK BASED NEWTON-LIKE BLENDING INTERPOLATION

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Journal of Computational Mathematics 2006年第4期24卷 515-526页

作者： Qian-jin zhao Jie-qing Tan School of Computer and Information Hefei University of Technology Hefei 230009 China Department of Mathematics and Physics Anhui University of Science and Technology Huainan 232001 China Institute of Applied Mathematics Hefei University of Technology Hefei 230009 China

Newton＇s polynomial interpolation may be the favourite linear interpolation in the sense that it is built up by means of the divided differences which can be calculated recursively and produce useful intermediate results. However Newton interpolation is in fact point based interpolation since a new interpolating polynomial with one more degree is obtained by adding a new support point into the current set of support points once at a time. In this paper we extend the point based interpolation to the block based interpolation. Inspired by the idea of the modern architectural design, we first divide the original set of support points into some subsets （blocks）, then construct each block by using whatever interpolation means, linear or rational and finally assemble these blocks by Newton＇s method to shape the whole interpolation scheme. Clearly our method offers many flexible interpolation schemes for choices which include the classical Newton＇s polynomial interpolation as its special case. A bivariate analogy is also discussed and numerical examples are given to show the effectiveness of our method.

关键词： Interpolation Block based divided differences Blending method.

Pore-scale simulation of water/oil displacement in a water-wet channel

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 803-814页

作者： jin zhao Guice Yao Dongsheng Wen School of Chemical and Process Engineering University of LeedsLeeds LS29JTUK School of Aeronautic Science and Engineering Bcihang UniversityBeijing 100191China

Water/oil flow characteristics in a water-wet capillary were simulated at the pore scale to increase our understanding on immiscible flow and enhanced oil *** of fluid method was used to capture the interface between oil and water and a pore-throat connecting structure was established to investigate the effects of viscosity,interfacial tension(IFT)and capillary number(Ca).The results show that during a water displacement process,an initial continuous oil phase can be snapped off in the water-wet pore due to the capillary *** altering the viscosity of the displacing fluid and the IFT between the wetting and non-wetting phases,the snapped-off phenomenon can be eliminated or reduced during the displacement.A stable displacement can be obtained under high Ca number *** displacement effects can be obtained at the same Ca number due to its significant influence on the flow state,i.e.,snapped-off flow,transient flow and stable flow,and ultralow IFT alone would not ensure a very high recovery rate due to the fingering flow occurrence.A flow chart relating flow states and the corresponding oil recovery factor is established.

关键词： VOF pore scale immiscible displacement EOR snap-off Ca

Yb^(3+)-and Er^(3+)-doped Y_(2)O_(3) microcrystals for upconversion photoluminescence and energy transfer with enhancements of near-ultraviolet emission

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Rare Metals 2021年第1期40卷 123-127页

作者： jin-Bo zhao Li-Li Wu School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Key Laboratory for Liquid-Solid Structural Evolution and Process of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China

Yb^(3+)and Er^(3+)were doped into Y_(2)O_(3) to form Y_(2)O_(3):Yb^(3+),Er^(3+)*** effect of doping concentration of Yb^(3+)was *** near-ultraviolet(UV)upconversion(UC)emission spectra of Y_(2)O_(3):Yb^(3+),Er^(3+)were studied under 1.55-μm *** near-UV UC emissions centered at 391 and 418 nm were enhanced by Yb^(3+)under 1.55-μm laser ***^(3+)generally acts as activator and is not used as sensitizer in the reference Er^(3+)-doped *** the present upconversion process under the 1.55-μm laser excitation,the energy transfer from Er^(3+)to Yb^(3+)and then Yb^(3+)to Er^(3+)was *** Er^(3+)acted as not only activator but also *** energy transfer between Er^(3+)and Yb^(3+)enhanced the near-UV UC emission of our materials.

关键词： Upconversion Photoluminescence Y_(2)O_(3):Yb^(3+)/Er^(3+) 1.55-μm excitation Optical materials and properties

Consuming fermented distillers＇ dried grains with solubles (DDGS) feed reveals a shift in the faecal microbiota of growing and fattening pigs using 454 pyrosequencing

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Journal of Integrative Agriculture 2017年第4期16卷 900-910页

作者： WANG jin HAN Ye zhao jin-zhao ZHOU Zhi-jiang FAN Huan School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P.R.China Tianjin Kuntai Environment & Energy Science and Technology Development Co. Ltd. Tianjin 300191 P.R. China Tianjin Animal Science and Veterinary Research Institute Tianjin 300381 P.R.China Key Laboratory of Systems Bioengineering Ministry of Education Tianjin 300072 P.R China

The objective of this study was to investigate pig fed by Bacillus coagulans-fermented distillers＇ dried grains with solubles （DDGS） on the faecal microbial composition and diversity using 454 pyrosequencing. Healthy crossbred （Durocx Yorkshirex Landrace） growing and fattening pigs （n=48）, with an average initial body weight of 65 kg, were divided into two groups （24 replicates per group; four pens per group; six pigs per pen）, and given either DDGS feed as the control, or B. coagulans-fermented DDGS feed as the treatment. Faecal samples were collected on day 0, 7, 14, 21, and 28. DNA was extracted, and the V3-V6 region of the 16S rRNA gene was amplified. The fermented DDGS feed affected the relative abundance of bacteria populations at the phylum, genus, and species levels. At the genus level, the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella, Lactobacillus, Clostridium, Bifidobacterium, Roseburia, and Bacillus, and lower relative abundances of faecal Escherichia, Ruminococcus, Dialister, unclassified Lachnospiraceae, unclassified Ruminococcaceae, and unclassified Enterobacteriaceae than in the control. At the species level, the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella sp., Lactobacillus johnsonii, Lactobacillus fermentum, Lactobacillus mucosae, Lactobacillus reuteri, Clostridium butyricum, Bifidobacterium sp., and Roseburia sp., and lower relative abundances of faecal Prevotella copri, Escherichia coil, Ruminococcus gnavus, Ruminococcus flavefaciens, and Dialister sp. than in the control. Principal coordinates analysis indicated a distinct separation in the faecal microbial communities of pigs that were fed the fermented and unfermented DDGS feed. Fermented DDGS feed significantly increased the average daily gain （ADG） of pigs, and significantly decreased the average daily feed intake （ADFI） of feed and feed/gain （F/G）. Thus, our results demonstrate a beneficial shift in t

关键词： faecal microbiota growing and fattening pigs pyrosequencing fermented DDGS feed