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基于改进的TF-IDF标签权重算法的电商用户画像构建

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信息技术与信息化 2024年第8期 48-51页

作者：白雨珂卢胜男西安石油大学陕西西安710065

在电商环境中,用户画像构建是为了更好地理解和满足用户需求而进行的重要任务。传统的TF-IDF标签权重计算方法无法很好地对标签权重进行调整,为了解决这一问题,提出基于TF-IDF算法的改进方法,旨在提高用户画像的准确性和个性化程度。融... 详细信息

在电商环境中,用户画像构建是为了更好地理解和满足用户需求而进行的重要任务。传统的TF-IDF标签权重计算方法无法很好地对标签权重进行调整,为了解决这一问题,提出基于TF-IDF算法的改进方法,旨在提高用户画像的准确性和个性化程度。融合相关系数矩阵,对相关性强的标签进行适当降权操作。不同类型的行为对标签信息产生不同的权重,并且标签的权重可能会随着时间的推移而衰减。因此,采用拟合记忆遗忘曲线模拟得到的兴趣遗忘曲线,对用户画像权重进行调优操作。实验结果表明,使用所提出的改进的TF-IDF算法构建用户画像的效果得到显著的提升。

关键词：电商相关系数标签权重用户画像 TF-IDF算法

骨科病人对健康类手机应用程序应用及其需求情况调查

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护理研究（中旬版） 2016年第10期30卷 3688-3692页

作者：白雨可穆红肖倩北京首都国际机场医院首都医科大学宣武医院首都医科大学护理学院

[目的]了解骨科病人对健康类手机应用程序(App)应用及其需求情况,为开发适合骨科病人的健康类手机App,更好地实现延续性护理提供依据。[方法]采用自行设计的调查问卷对首都医科大学宣武医院骨科病房及门诊的171例病人进行调查。[结果]97... 详细信息

[目的]了解骨科病人对健康类手机应用程序(App)应用及其需求情况,为开发适合骨科病人的健康类手机App,更好地实现延续性护理提供依据。[方法]采用自行设计的调查问卷对首都医科大学宣武医院骨科病房及门诊的171例病人进行调查。[结果]97.1%的骨科病人使用的是智能手机,76.6%的病人每天使用手机,病人的手机使用经验处于中等水平(46.0分±12.8分),具有良好的手机使用经验基础;86.0%的病人在手机上安装并使用过健康类App,使用较多的软件类别包括骨科康复类App(61.9%)、健康饮食类App(58.5%)、健康运动类App(57.8%)和求医咨询类App(39.5%)等;使用健康相关App的主要原因为:预防疾病与自身保健(81.6%),监测疾病及身体状况(66.7%),康复锻炼(57.1%),求医问药(40.1%)等;如果医院开发一种适合骨科病人的App,88.9%的病人表示愿意安装软件,并具有较好的使用信心;病人期望该类App具有的主要功能为:能够根据病人的情况进行及时的反馈和指导(89.5%),能够推荐医生、帮助挂号(84.8%),能提供实用的方法有图或视频(83.6%),能够记录和监测健康变化(79.5%),能够提供疾病知识(74.9%)等;希望此类软件的界面特点为:简单且好操作(63.7%),实用、具体、有指导性(56.1%),不要有广告植入(53.2%)等。[结论]绝大多数骨科病人具有使用骨科健康App的硬件基础和经验基础,应针对病人的需求开发具有针对性的骨科健康软件,实现延续性护理服务,促进病人康复。

关键词：骨科病人智能手机健康教育应用程序

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砷化镓晶片表面损伤层分析

稀有金属 1999年第4期23卷 241-244页

作者：郑红军卜俊鹏曹福年白玉柯吴让元惠峰何宏家中国科学院半导体研究所

采用ＴＥＭ观测与Ｘ射线双晶回摆曲线检测化学腐蚀逐层剥离深度相结合的方法，分析了ＳＩＧａＡｓ晶片由切、磨、抛加工所引入的损伤层深度。比较两种方法测量结果上的差异，得出了ＴＥＭ观测到的只是晶片损伤层厚度。

关键词：砷化镓切片磨片抛光片表面损伤层晶片

The influencing mechanism of O_(2),H_(2)O,and CO_(2)on the H_(2)S removal of food waste digestate-derived biochar with abundant minerals

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Biochar 2022年第1期4卷 7-24页

作者： Dandan Huang Ning Wang Xinyue bai yuke Chen Qiyong Xu Shenzhen Campus of Sun Yat-Sen University No.66Gongchang RoadGuangming DistrictShenzhen 518107China. Shenzhen Engineering Laboratory for Eco-Efficient Recycled Materials School of Environment and EnergyPeking University Shenzhen Graduate SchoolUniversity TownXiliNanshan DistrictShenzhen 518055China. Ministry of Education Key Laboratory for Ecology of Tropical Islands College of Life and SciencesHainan Normal UniversityHaikou 571158China

Hydrogen sulfide(H_(2)S)removal has been a significant concern in various *** this study,food waste diges-tate-derived biochar(DFW-BC),a by-product of food waste treatment with abundant minerals,was assessed for removing H_(2)S from different simulated biogas containing oxygen(O_(2))and carbon dioxide(CO_(2))and under differ-ent moisture(H_(2)O)contents(0%and 20%)of *** influencing mechanisms of the gas conditions combined with the moisture contents were also *** results showed an H_(2)S removal of 1.75 mg g^(−1)for dry bio-char under pure H_(2)S,4.29 mg g^(−1)for dry biochar under H_(2)S+O_(2),5.29 mg g^(−1)for humid biochar under H_(2)S,and 12.50 mg g^(−1)for humid biochar under H_(2)S+O_(2).For dry DFW-BC,the high Fe content was responsible for the O_(2)*** contrast,O_(2)+H_(2)O activated the catalytic H_(2)S oxidation of the less reactive minerals(mainly Ca).The inhibition of CO_(2)on H_(2)S adsorption was not obvious for dry DFW-BC;the specific pore structure may have provided a buffer against the physisorption competition of CO_(2).However,when H_(2)O was present on DFW-BC,the changes in critical biochar properties and sulfur speciation as opposed to that without H_(2)O implied an evident occurrence of CO_(2)*** CO_(2)chemisorption partially hindered O_(2)+H_(2)O enhancement,decreasing the H_(2)S removal capacity from 12.50 to 8.88 mg g^(−1).The negative effect was ascribed to mineral carbonation of CO_(2),neutralizing the alkaline surface and immobilizing metal oxides,which thus reduced the acceleration in H_(2)S dissociation and activa-tion in catalytic H_(2)S oxidation by O_(2)+H_(2)O.

关键词： Hydrogen sulfide Carbon Digestate Adsorption Desulfuration Deodorization

BcpLH organizes a specific subset of microRNAs to form a leafy head in Chinese cabbage(Brassica rapa ***)

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Horticulture Research 2020年第1期7卷 2733-2745页

作者： Wenqing Ren Feijie Wu Jinjuan bai Xiaorong Li Xi Yang Wanxin Xue Heng Liu yuke He National Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesFenglin Road 300Shanghai 200032China Graduate School of the Chinese Academy of Sciences Shanghai 200032China South Subtropical Crop Research Institute Chinese Academy of Tropical Agricultural SciencesMinistry of AgricultureZhanjiangGuangdongChina

HYL1(HYPONASTIC LEAVES 1)in Arabidopsis thaliana encodes a double-stranded RNA-binding protein needed for proper miRNA maturation,and its null mutant hyl1 shows a typical leaf-incurvature *** Chinese cabbage,BcpLH(Brassica rapa *** LEAFY HEADS),a close homolog of HYL1,is differentially expressed in juvenile leaves,which are flat,and in adult leaves,which display extreme *** lacks protein–protein interaction domains and is much shorter than *** test whether BcpLH is associated with defects in microRNA(miRNA)biogenesis and leaf flatness,we enhanced and repressed the activity of BcpLH by transgenics and investigated BcpLH-dependent miRNAs and plant *** promoted miRNA biogenesis by the proper processing of primary *** downregulation via antisense decreased a specific subset of miRNAs and increased the activities of their target genes,causing upward curvature of rosette leaves and early leaf incurvature,concurrent with the enlargement,earliness,and round-to-oval shape transition of leafy ***,BcpLH-dependent miRNAs in Chinese cabbage are not the same as HYL1-dependent miRNAs in *** suggest that BcpLH controls a specific subset of miRNAs in Chinese cabbage and coordinates the direction,extent,and timing of leaf curvature during head formation in Brassica rapa.

关键词： curvature subset shorter

Alternatively spliced BobCAL transcripts alter curd morphotypes in a collection of Chinese cauliflower accessions

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Horticulture Research 2020年第1期7卷 649-661页

作者： Wenguang Cao Biting Cao Xuan Wang Jinjuan bai Yong-Zhen Xu Jianjun Zhao Xiaorong Li yuke He Shengwu Hu National Laboratory of Plant Molecular Genetics Center for Excellence in Molecular Plant SciencesShanghai Institutes of Plant Physiology&EcologyChinese Academy of Science300 Fenglin RoadShanghai 200032China State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy Northwest A&F UniversityYanglingShaanxiChina State Key Laboratory of North China Crop Improvement and Regulation Department of HorticultureHebei Agricultural UniversityBaoding 071001China

The curd of cauliflower(Brassica oleracea ***)is a modified inflorescence that is consumed as a *** formation is proposed to be due to a mutation in the BobCAULIFLOWER(BobCAL)gene,but the genetic relationship between BobCAL variation and curd morphotypes remains *** address this question,we collected and classified a collection of 78 cauliflower accessions into four subpopulations according to curd surface features:smooth,coarse,granular,and hairy curd *** the cDNA sequencing of BobCAL alleles,we showed that smooth and coarse accessions characterized by inflorescence meristem arrest presented a strong association with the 451T SNP(BobCAL_T),whereas granular and hairy accessions marked with floral organ arrest presented an association with 451G(BobCAL_G).Interestingly,all BobCAL alleles were alternatively spliced,resulting in a total of four alternative splice(AS)variants due to the retention of the fourth and/or seventh *** accessions with BobCAL_G alleles,the total expression of all these AS variants in granular plants was almost equal to that in hairy plants;however,the expression of the individual AS variants encoding intact proteins relative to those encoding truncated proteins *** accessions showed relatively high expression of the individual variants encoding intact proteins,whereas granular accessions displayed relatively low *** smooth cauliflower,the overexpression of the BobCAL_Ga variant caused an alteration in the curd morphotype from smooth to hairy,concurrent with an increase in the expression levels of downstream floral identity *** results reveal that alternative splicing of BobCAL transcripts is involved in the determination of cauliflower curd morphotypes.

关键词： collection retention floral

Tuning growth cycles of Brassica crops via natural antisense transcripts of BrFLC

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Tuning growth cycles of Brassica crops via natural antisense...

Conditional Kernel Covariance and Correlation

2016年全国植物生物学大会

作者： Xiaorong Li Shaofeng Zhang Jinjuan bai Yajie Li yuke He National Key Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of Sciences

Several oilseed and vegetable crops of Brassica are biennials that require a prolonged winter cold for flowering,a process called vernalization. FLOWERING LOCUS C(FLC) is a central repressor of flowering. Here,we report that the overexpression of natural antisense transcripts(NATs) of Brassica rapa FLC(Br FLC) greatly shortens plant growth cycles. In rapid-,medium-and slow-cycling crop types,there are four copies of the BrFLC genes,which show extensive variation in sequences and expression levels. In Bre,a biennial crop type that requires vernalization,five NATs derived from the BrFLC2 locus are rapidly induced under cold conditions,while all four BrFLC genes are gradually down-regulated. The transgenic Bre lines overexpressing a long NAT of BrFLC2 do not require vernalization,resulting in a gradient of shortened growth cycles. Among them,a subset of lines both flower and set seeds as early as Yellow sarson,an annual crop type in which all four BrFLC genes have nonsense mutations and are non-functional in flowering repression. Our results demonstrate that the growth cycles of biennial crops of Brassica can be altered by changing the expression levels of BrFLC2 NATs. Thus,BrFLC2 NATs and their transgenic lines are useful for the genetic manipulation of crop growth cycles.

关键词： Brassica rapa BrFLC natural antisense transcripts flowering time growth cycle vernalization

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数学进展 2024年第6期53卷 1158-1172页

作者： bai Qianxue SHI yuke YANG Qing LI Qizhai Institute of Systems Science Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences School of Mathematics and Statistics South-Central Minzu University

The conditional kernel correlation is proposed to measure the relationship between two random variables under covariates for multivariate *** on the framework of reproducing kernel Hilbert spaces,we give the definitions of the conditional kernel covariance and conditional kernel *** also provide their respective sample estimators and give the asymptotic properties,which help us construct a conditional independence *** to the numerical results,the proposed test is more effective compared to the existing one under the considered scenarios.A real data is further analyzed to illustrate the efficacy of the proposed method.

关键词： conditional kernel correlation reproducing kernel Hilbert space conditional independence test

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顾及用户画像的多源遥感信息智能推荐方法

测绘学报 2023年第2期52卷 297-306页

作者：龙恩吕守业岑鹏瑞杨宇科韦二龙白龙北京市遥感信息研究所北京100011 中国电子科技集团公司第五十四研究所河北石家庄050081

近年来,我国各类卫星井喷式发展,随之带来的海量卫星遥感数据保障服务的主动性不够、个性化不足等现实问题日益凸现,严重制约了卫星遥感的多领域智能应用。本文针对该问题,设计了一种顾及用户画像的遥感信息智能推荐方法。首先,构建融... 详细信息

近年来,我国各类卫星井喷式发展,随之带来的海量卫星遥感数据保障服务的主动性不够、个性化不足等现实问题日益凸现,严重制约了卫星遥感的多领域智能应用。本文针对该问题,设计了一种顾及用户画像的遥感信息智能推荐方法。首先,构建融时间、空间、载荷、分辨率、产品级别5项核心元素的可扩展主题用户画像模型;然后,对模型中各元素权重、区间长度、分布特征值等进行具体表达,给出解算方法;最后,结合各元素权重及兴趣特征值,计算待分发数据与用户兴趣特征值的关联度,定量解算推荐度,实现遥感数据有序智能推荐。对国家减灾中心和北京市公安局禁毒总队两个用户近3 a实际需求订单的试验结果表明,该模型方法解算构建的各主题元素分布特征符合用户实际应用特点,推荐度较高,平均优于94%。研究成果为工程化实现天基遥感信息个性化服务及智能推荐提供了模型方法。

关键词：天基遥感用户画像主题元素智能推荐

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