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Corpus-based research on English word recognition rates in primary school and word selection strategy

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Frontiers of Information Technology & Electronic Engineering 2017年第3期18卷 362-372页

作者： Wen-yan XIAO Ming-wen WANG Zhen WENG Li-lin ZHANG Jia-li ZUO School of Computer Information Engineering Jiangxi Normal UniversityNanchang 330022China Jiangxi University of Science and Technology Nanchang 330003China

Acquiring vocabulary is important when studying English, as it assists in listening, speaking, reading, and writing. In this paper, we develop an English webpage corpus(EWC) and create a word frequency list using web crawler technology. By comparing EWC word lists with the British National Corpus(BNC), we find that the BNC word frequency list possesses the feature of timeliness. We also explore primary school students' English word recognition rates by comparing the word frequency lists of several corpora, including EWC, BNC, SUBTLEX-US, and Subtitle Corpus of Children's BBC(CBBC). The results show that the word recognition rates for primary school children are relatively low in both general language and specific language register. Motivated by the experiment results, we finally propose some word-selection strategies for compiling English textbooks for Chinese primary school students.

关键词： Corpus Primary English Recognition rate Word frequency coverage rate

EMPIRICAL LIKELIHOOD CONFIDENCE REGION FOR PARAMETERS IN LINEAR ERRORS-IN-VARIABLES MODELS WITH MISSING DATA

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Journal of Systems Science & Complexity 2011年第3期24卷 540-553页

作者： Juan ZHANG Hengjian CUI Department of Statistics Capital University of Economics and Business Beijing 100070 China. Department of Statistics and Financial MatheTnatics School of Mathematical Sciences Beijing Normal University Beijing 100875 China School of Mathematical Sciences Capital Normal University Beijing 100048 China

The multivariate linear errors-in-variables model when the regressors are missing at random in the sense of Rubin （1976） is considered in this paper. A constrained empirical likelihood confidence region for a parameter β0 in this model is proposed, which is constructed by combining the score function corresponding to the weighted squared orthogonal distance based on inverse probability with a constrained region of β0. It is shown that the empirical log-likelihood ratio at the true parameter converges to the standard chi-square distribution. Simulations show that the coverage rate of the proposed confidence region is closer to the nominal level and the length of confidence interval is narrower than those of the normal approximation of inverse probability weighted adjusted least square estimator in most cases. A real example is studied and the result supports the theory and simulation＇s conclusion.

关键词： Confidence region coverage rate empirical likelihood ratio multivariate linear errors-in- variables model weighted adjusted LS estimation.

Future changes in coverage of 1.5℃ and 2℃warming thresholds

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Science Bulletin 2017年第21期62卷 1455-1463页

作者： di tian wenjie dong han zhang yan guo shili yang tanlong dai State Key Laboratory of Stllite Ocean Environment Dynamics Second Instiute of OceanographyHangzhou 310012China School of Atmospheric Sciences Sun Yat-Sen UniversityGuangzhou 510275China Zhuhai Joint Innovative Center for Climate-Environment-Ecosystem Future Earth Research InstituteBeijing Normal UniversityZhuhai 519087China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

The areas covered by 1.5 ℃ and 2.0 ℃ warming thresholds under RCP2.6, RCP4.5, and RCP8.5 were analyzed based on 22 CMIP5 models. More than 90% of the model runs are in agreement that by the end of the 21 st century, near-surface air temperature changes over ~5%(~2%), ~40%(~18%), and ~92%(~86%)of the globe will cross the 1.5 ℃(2.0 ℃) threshold under RCP2.6, RCP4.5, and RCP8.5, respectively. Under RCP8.5, nearly the whole of North America, Europe + Russia, Africa, and Asia–Russia will cross the 1.5 ℃(2.0 ℃) threshold in ~2050(~2060), while the coverage rates over South America and Oceania are ~80%(~75%) and ~50%(~30%), respectively. The threshold-onset time(TOT) for 2 ℃ warming is earliest over Europe + Russia and North America, followed by Africa, Asia–Russia, South America, and finally Oceania under the RCP4.5 and RCP8.5 scenarios. The TOT for 1.5 ℃ is ~10–30 years ahead of that for 2.0 ℃.

关键词： 2℃ threshold 1.5℃ threshold CMIP5 coverage rate

Blend with the Sea Surface Temperature from Different Satellites and Their Comparison in the Southeast Pacific Ocean

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Journal of Ocean University of China 2023年第2期22卷 452-458页

作者： WU Yumei TANG Fenghua DAI Yang WANG Fei SHI Yongchuang ZHANG Shengmao Key and Open Laboratory of Remote Sensing Information Technology in Fishing Resource East China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesShanghai 200090China Key Laboratory of Fisheries Remote Sensing Ministry of Agriculture and Rural Affairs Shanghai 200090China

The daily sea surface temperature(SST)data from three kinds of different satellites of GMI,GOES and MODIS were applied to do the blend in the Southeast Pacific Ocean throughout the whole year of *** coverage rates of the SST of the blend result were improved highly and more stable throughout the whole year,compared with the result of the single satellite of GMI,GOES,and *** yearly average coverage rates of GMI,GOES,MODIS,and blend were 43%,48%,30%,and 76%,and their corresponding yearly average standard deviation(SD)were 4%,6%,7%,and 4%,*** the coverage rates of these three satellites were low from April to *** valid observation days calculated in the whole year over every grid were used to represent the spatial distribution patterns of the coverage *** spatial distribution patterns of coverage rates from GOES and MODIS were similar that their valid observation days were higher in the northwest area and lower in the south area,and those of GMI was contrary to the former *** ranges of valid observation day was from GOES,GMI,and MODIS were 0-364,6-254,and 9-231 d,*** the blend,all the observation day of every grid in the research region was enhanced(103-366 d).Especially the near shore and south area,and the minimum valid observation day increased largely from the single digits to hundreds digit.

关键词： sea surface temperature blend coverage rate observation day

Quantifying muskmelon fruit attributes with A-TEP-based model and machine vision measurement

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Journal of Integrative Agriculture 2018年第6期17卷 1369-1379页

作者： CHANG Li-ying HE San-peng LIU Qian XIANG Jia-lin HUANG Dan-feng School of Agriculture and Biology Shanghai Jiaotong University

In this study, we established a dynamic morphological model using the accumulated thermal effectiveness and photosynthetic active radiation （PAR）（A-TEP）, aiming to explore the relationship between muskmelon （Cucumis melo L.） fruit attributes and environmental factors. Muskmelon surface color was described by parameters of red, green, blue, hue, saturation and brightness （HSI）. Three characteristic parameters, gray level co-occurrence matrix （GLCM）, angular second moment （ASM）, entropy, contrast, and the coverage rate were used to describe the process of muskmelon fruit netting formation. ASM was not significant difference during muskmelon fruit growth. The number and deep of netting stripes gradually increased with fruit growth. coverage rate increased rapidly for 15-30 d after pollination. The vertical and horizontal diameters of muskmelon fruit were followed a logistic curve. And root mean squared errors （RMSE） between the simulated and measured vertical and horizontal diameters were 3.527 and 4.696 mm, respectively. RMSE of red, green, blue, saturation and brightness were 0.999, 2.690, 2.992, 0.033 and 5.51, respectively, and the RMSE for entropy, contrast and coverage rates were 0.077, 0.063 and 0.015, respectively, indicating a well consistent between measured and simulated values.

关键词： machine vision technology fruit attributes A-TEP skin netting coverage rate

Hydration mechanisms of smithsonite from DFT-D calculations and MD simulations

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International Journal of Mining Science and Technology 2022年第3期32卷 605-613页

作者： Yuanjia Luo Leming Ou Jianhua Chen Guofan Zhang Yuqin Xia Bohan Zhu Hanyu Zhou School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China College of Resources and Metallurgy Guangxi UniversityNanning 530004China

Investigation on the mineralwater interactions is crucial for understanding the subsequent interfacial ***,the hydration mechanisms of smithsonite are still *** this paper,the adsorption of H_(2)O at different coverage rates on smithsonite(101)surface was innovatively investigated using density-functional theory(DFT)calculations and molecular dynamics(MD)simulations by analyzing adsorption model,interaction energy,atomic distance,density of state,electron density difference,concentration profile,radial distribution function and self-diffusion *** found that single H_(2)O preferred to be dissociated on smithsonite(101)surface via the interaction of surface Zn with the Ow of H_(2)O and H-bond between Hw of H_(2)O and surface ***,dissociation adsorption and molecular adsorption coexisted on the smithsonite surface at a high coverage rate of H_(2)O,and dissociation adsorption remained the main adsorption ***,we found the interaction between smithsonite surface and H_(2)O was weakened as a function of H_(2)O coverage,which was because the presence of interlayer H_(2)O and different layers of H_(2)O decreased the reactivity of the smithsonite *** H_(2)O is mainly adsorbed on the smithsonite surface by forming three layers of H_(2)O(about 10–15Å),with the ordering degree gradually decreasing.

关键词： H_(2)O Smithsonite surface DFT MD coverage rate

Method for UAV spraying pattern measurement with PLS model based spectrum analysis

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 22-28页

作者： Ruirui Zhang Yao Wen Longlong Li Liping Chen Gang Xu Yanbo Huang Qing Tang Tongchuan Yi National Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China Beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China National Center for International Research on Agricultural Aerial Application Technology Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China Beijing Key laboratory of Intelligent Equipment Technology for Agriculture Beijing Academy of Agricultural And Forestry SciencesBeijing 100097China United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStoneville MS 38776USA

Unmanned aerial vehicle(UAV)chemical application is widely used for crop protection,and spraying pattern is one of the most important factors that influence the chemical control efficacy.A method for UAV spraying pattern measurement with partial least squares(PLS)model based spectrum analysis was proposed in this study to measure the UAV spraying pattern more *** method involved the steps of fluorescent tracer solution spray and its droplets collection,the spectrum on paper strip acquiring,spectrum processing and analysis,PLS *** order to verify the applicability of the method and obtain the parameters of the PLS model,UAV spraying experiments were performed in the *** Fluorescent tracer solution was sprayed and its droplets are collected by paper strip,and the original spectrum on paper strip obtained by a spectrometer was processed by the Savitzky-Golay and standard normalized variable(SNV)*** prediction model of coverage rate selected as the droplet deposition parameter to measure the UAV spraying pattern,was established by using PLS *** verify the superiority of the PLS model,a traditional linear regression(LR)model of coverage rate was established *** results demonstrate that the method with PLS model based spectrum analysis can measure the UAV spraying pattern effectively,and PLS model has a better performance of RV2=0.94 and RMSEP=0.9446 than that of the LR model.

关键词： pattern measurement UAV spraying spectrum model coverage rate partial least squares method

Factors associated with coverage of praziquantel for schistosomiasis control in the communitydirect intervention (CDI) approach in Mali (West Africa)

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Infectious Diseases of Poverty 2013年第1期2卷 82-92页

作者： Abdoulaye Dabo Boubacar Bary Bourema Kouriba Oumar Sankaré Ogobara Doumbo Department of Epidemiology of Infectious Diseases Faculty of MedicinePharmacy and DentistryUMI 3189University of SciencesTechniques and Technologies of BamakoBox 1805BamakoMali High Institute for Training and Applied Research Box 475EBamakoMali

Background:Despite the progress made in the control of Neglected Tropical Diseases(NTD),schistosome and soil-transmitted helminth infections are far from being effectively managed in many parts of the ***,the key element of all control strategies,is faced with some difficulties in terms of access to *** study aims to describe the factors involved in the success or failure of the community-directed intervention(CDI)approach through control programmes,which aims to achieve consistent high coverage at affordable and sustainable costs in endemic ***:The CDI approach was carried out from December 2007 to October 2008 in ten villages of the district of Diéma,*** inclusion,each child part of the study’s sample was interviewed and submitted for a physical *** study focused on:data collection,treatment of the eligible population,evaluation of the treatment coverage,performance of community drug distributors(CDDs),and the involvement and perception of ***:A total of 8,022 eligible people were studied with a mean coverage rate of 76.7%.Using multiple regression,it was determined that receiving praziquantel as treatment was associated with five factors:belonging to the Fulani or Moorish ethnic minority versus the Bambara/Soninke,use of the central versus the house-to-house drug distribution mode,the ratio of the population to the number of CDDs,the lack of supervision and belonging to the age group of 15 years or above(p<0.05).As well as that,it was found that the presence of parallel community-based programmes(HIV,tuberculosis)that provide financial incentives for community members discouraged many CDDs(who in most cases are volunteers)to participate in the CDI approach due to a lack of ***:The findings indicate that the success of the CDI approach depends on,amongst other things,the personal characteristics of the respondents,as well as on community factors.

关键词： Schistosomiasis Praziquantel Community-directed intervention coverage rate Diéma Mali

农民工养老保险的覆盖率：传统保障还起作用吗？

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