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Orbit Weighting Scheme in the Context of Vector Space Information Retrieval
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作者 Ahmad Ababneh Yousef Sanjalawe +2 位作者 Salam Fraihat Salam Al-E’mari Hamzah Alqudah 《Computers, Materials & Continua》 SCIE EI 2024年第7期1347-1379,共33页
This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schem... This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schemes like tf-idf and BM25.These conventional methods often struggle with accurately capturing document relevance,leading to inefficiencies in both retrieval performance and index size management.OWS proposes a dynamic weighting mechanism that evaluates the significance of terms based on their orbital position within the vector space,emphasizing term relationships and distribution patterns overlooked by existing models.Our research focuses on evaluating OWS’s impact on model accuracy using Information Retrieval metrics like Recall,Precision,InterpolatedAverage Precision(IAP),andMeanAverage Precision(MAP).Additionally,we assessOWS’s effectiveness in reducing the inverted index size,crucial for model efficiency.We compare OWS-based retrieval models against others using different schemes,including tf-idf variations and BM25Delta.Results reveal OWS’s superiority,achieving a 54%Recall and 81%MAP,and a notable 38%reduction in the inverted index size.This highlights OWS’s potential in optimizing retrieval processes and underscores the need for further research in this underrepresented area to fully leverage OWS’s capabilities in information retrieval methodologies. 展开更多
关键词 Information retrieval orbit weighting scheme semantic text analysis tf-idf weighting scheme vector space model
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基于TF-IDF算法的运营商客户投诉原因研究 被引量:1
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作者 张爱华 孙嘉鸿 《北京邮电大学学报(社会科学版)》 2024年第2期39-49,共11页
针对运营商人工处理客户投诉工单高成本低效率问题,提出了一种基于TF-IDF算法的定量研究方法,旨在高效精准地识别客户投诉原因。选用Jieba分词,导入自定义词典和停用词列表,对运营商客户投诉工单进行关键词抽取,获取各类问题中TF-IDF值... 针对运营商人工处理客户投诉工单高成本低效率问题,提出了一种基于TF-IDF算法的定量研究方法,旨在高效精准地识别客户投诉原因。选用Jieba分词,导入自定义词典和停用词列表,对运营商客户投诉工单进行关键词抽取,获取各类问题中TF-IDF值排名前6的关键词,输出关键词集。提高了关键词抽取的准确性和效率。此外,对比仅对文档集使用TF进行统计和使用TextRank算法的情况,突显了IDF的重要性及算法原理的差异。实验结果表明,光猫、路由器、机顶盒问题广泛存在于各类投诉中。针对这三类问题,为运营商提供了改进产品、服务的相关建议,对运营商集中治理、解决问题具有一定的实用价值。 展开更多
关键词 投诉工单 投诉原因 关键词抽取 tf-idf
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基于TF-IDF和多头注意力Transformer模型的文本情感分析 被引量:9
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作者 高佳希 黄海燕 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期129-136,共8页
文本情感分析旨在对带有情感色彩的主观性文本进行分析、处理、归纳和推理,是自然语言处理中一项重要任务。针对现有的计算方法不能充分处理复杂度和混淆度较高的文本数据集的问题,提出了一种基于TF-IDF(Term Frequency-Inverse Documen... 文本情感分析旨在对带有情感色彩的主观性文本进行分析、处理、归纳和推理,是自然语言处理中一项重要任务。针对现有的计算方法不能充分处理复杂度和混淆度较高的文本数据集的问题,提出了一种基于TF-IDF(Term Frequency-Inverse Document Frequency)和多头注意力Transformer模型的文本情感分析模型。在文本预处理阶段,利用TF-IDF算法对影响文本情感倾向较大的词语进行初步筛选,舍去常见的停用词及其他文本所属邻域对文本情感倾向影响较小的专有名词。然后,利用多头注意力Transformer模型编码器进行特征提取,抓取文本内部重要的语义信息,提高模型对语义的分析和泛化能力。该模型在多领域、多类型评论语料库数据集上取得了98.17%的准确率。 展开更多
关键词 文本情感分析 自然语言处理 多头注意力机制 tf-idf算法 Transformer模型
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基于改进TF-IDF融合二进制灰狼优化的短文本分类
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作者 杨东 毋涛 +1 位作者 赵雪青 李猛 《计算机技术与发展》 2024年第8期37-41,共5页
为了提高特殊类型短文本分类准确度和降低特征维度,提出了基于改进TF-IDF方法融合二进制灰狼优化的短文本分类。为了提高特征向量文本权重计算准确度,提出了点赞排列因子,并融合了文本特征集中度,对附有点赞数的特殊类型文本进行权重计... 为了提高特殊类型短文本分类准确度和降低特征维度,提出了基于改进TF-IDF方法融合二进制灰狼优化的短文本分类。为了提高特征向量文本权重计算准确度,提出了点赞排列因子,并融合了文本特征集中度,对附有点赞数的特殊类型文本进行权重计算,设计改进了TF-IDF-RANK方法对特征进行加权;同时,基于初选特征向量,设计优化了二进制灰狼优化算法(BGWO)搜寻最优特征子集,引入衰减系数向量和多优解迭代机制,提高灰狼搜寻性能。结果表明,该方法有效地提升了权重准确率,更好地表征初选特征向量,增强特征选择时寻找全局最优解的能力,进而提高短文本的分类效果。通过LABIC和抖音开放平台数据集测试,综合指标F1值分别提高了14.76%和14.02%,验证了该方法对于特殊类型文本分类的有效性。 展开更多
关键词 短文本分类 特征加权 tf-idf-RANK方法 特征选择 二进制灰狼优化
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Genetic dissection and validation of a major QTL for grain weight on chromosome 3B in bread wheat(Triticum aestivum L.) 被引量:2
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作者 Simin Liao Zhibin Xu +7 位作者 Xiaoli Fan Qiang Zhou Xiaofeng Liu Cheng Jiang Liangen Chen Dian Lin Bo Feng Tao Wang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期77-92,共16页
Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(... Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement. 展开更多
关键词 thousand-grain weight QTL mapping haplotype analysis candidate gene
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Screening biomarkers for spinal cord injury using weighted gene co-expression network analysis and machine learning 被引量:5
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作者 Xiaolu Li Ye Yang +3 位作者 Senming Xu Yuchang Gui Jianmin Chen Jianwen Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2723-2734,共12页
Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is s... Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is still limited understanding of the peripheral immune inflammato ry response in spinal cord inju ry.In this study.we obtained microRNA expression profiles from the peripheral blood of patients with spinal co rd injury using high-throughput sequencing.We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus(GEO)database(GSE151371).We identified 54 differentially expressed microRNAs and 1656 diffe rentially expressed genes using bioinformatics approaches.Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways,such as neutrophil extracellular trap formation pathway,T cell receptor signaling pathway,and nuclear factor-κB signal pathway,we re abnormally activated or inhibited in spinal cord inju ry patient samples.We applied an integrated strategy that combines weighted gene co-expression network analysis,LASSO logistic regression,and SVM-RFE algorithm and identified three biomarke rs associated with spinal cord injury:ANO10,BST1,and ZFP36L2.We verified the expression levels and diagnostic perfo rmance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve.Quantitative polymerase chain reaction results showed that ANO20 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients.We also constructed a small RNA-mRNA interaction network using Cytoscape.Additionally,we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal co rd injury patients using the CIBERSORT tool.The proportions of naive B cells,plasma cells,monocytes,and neutrophils were increased while the proportions of memory B cells,CD8^(+)T cells,resting natural killer cells,resting dendritic cells,and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects,and ANO10,BST1 and ZFP26L2we re closely related to the proportion of certain immune cell types.The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal co rd inju ry and suggest that ANO10,BST2,and ZFP36L2 are potential biomarkers for spinal cord injury.The study was registe red in the Chinese Clinical Trial Registry(registration No.ChiCTR2200066985,December 12,2022). 展开更多
关键词 bioinformatics analysis BIOMARKER CIBERSORT GEO dataset LASSO miRNA-mRNA network RNA sequencing spinal cord injury SVM-RFE weighted gene co-expression network analysis
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长三角一体化发展特征与动力探究——基于TF-IDF算法与格兰杰检验
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作者 关硕 赵雪 刘毅 《科技和产业》 2024年第5期40-47,共8页
从政策观念视角出发,深入探讨长三角区域一体化发展进程,有助于洞察区域内生发展动力和经济增长潜力。应用话语制度主义和间断-均衡框架,结合TF-IDF(词频-逆文档频率)算法与格兰杰检验,揭示长三角一体化发展特征与动因。研究发现:建设... 从政策观念视角出发,深入探讨长三角区域一体化发展进程,有助于洞察区域内生发展动力和经济增长潜力。应用话语制度主义和间断-均衡框架,结合TF-IDF(词频-逆文档频率)算法与格兰杰检验,揭示长三角一体化发展特征与动因。研究发现:建设主体对5个发展目标的注意力分配不均衡;在创新共建目标方面,地方主体的注意力变动会引起中央主体的注意力变动;长三角一体化发展呈现小间断大均衡特征,体现“自下而上”的地方主导模式。 展开更多
关键词 长三角一体化 话语制度主义 间断-均衡框架 tf-idf(词频-逆文件频率)算法 格兰杰检验
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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence 被引量:1
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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基于改进TF-IDF和AGLCNN的新闻长文本分类模型
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作者 周宪溪 牟莉 《计算机与现代化》 2024年第8期120-126,共7页
新闻长文本分类是自然语言处理中的一项重要任务,但传统的文本表示方法存在特征稀疏、语义不足等问题。此外,新闻长文本含有大量的冗余信息,并且可能涉及其他主题,以上问题都会导致文本特征提取不全面。为此,本文提出一种基于改进TF-ID... 新闻长文本分类是自然语言处理中的一项重要任务,但传统的文本表示方法存在特征稀疏、语义不足等问题。此外,新闻长文本含有大量的冗余信息,并且可能涉及其他主题,以上问题都会导致文本特征提取不全面。为此,本文提出一种基于改进TF-IDF算法和AGLCNN的新闻长文本分类模型。该模型首先利用特征项在类间与类内分布情况及其位置信息来改进TF-IDF算法,并结合Word2Vec词向量进行文本表示;利用注意力机制突出关键字信息,输入至Bi-LSTM捕获文本上下文特征;接着利用CNN突出新闻主题的显著特征;考虑到新闻长文本中可能存在涉及其他主题信息的句子,引入门控机制对Bi-LSTM和CNN输出特征进行融合,获得最终的文本特征表示;最后,将特征向量输入Softmax层进行新闻分类。在THUCNews数据集和搜狐新闻数据集上进行对比实验,结果表明,所提模型在2个数据集上的召回率分别为0.985和0.976,优于其他分类模型。 展开更多
关键词 文本分类 tf-idf 注意力机制 卷积神经网络 特征项
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Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study
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作者 Huijuan Ruan Yajie Zhang +6 位作者 Qingya Tang Xuan Zhao Xuelin Zhao Yi Xiang Wei Geng Yi Feng Wei Cai 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期254-264,共11页
Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term foll... Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers. 展开更多
关键词 Human milk Milk composition Body weight Body mass index(BMI) weight gain Postpartum weight retention
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TOEPLITZ OPERATORS BETWEEN WEIGHTED BERGMAN SPACES OVER THE HALF-PLANE
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作者 Lixia FENG Yan LI +1 位作者 Zhiyu WANG Liankuo ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1707-1720,共14页
In this paper,by characterizing Carleson measures,we investigate a class of bounded Toeplitz operator between weighted Bergman spaces with Békolléweights over the half-plane for all index choices.
关键词 weighted Bergman spaces Békolléweights Carleson measure Toeplitz operators
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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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作者 白雨珂 卢胜男 《信息技术与信息化》 2024年第8期48-51,共4页
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... 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。 展开更多
关键词 电商 相关系数 标签权重 用户画像 tf-idf算法
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Optimal investment based on relative performance and weighted utility
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作者 WANG Lei DONG Ying-hui HUA Chun-rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期328-342,共15页
This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance compariso... This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance. 展开更多
关键词 relative performance weighted utility S-shaped utility CONCAVIFICATION
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Effect of Molecular Weight on Thermoelectric Performance of P3HT Analogues with 2-Propoxyethyl Side Chains
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作者 董得福 WANG Wei +3 位作者 ZHAN Chun LI Chenglong ZHOU Qisheng 肖生强 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared h... By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared herein in addition with step increment of about 7 kDa on numberaverage molecular weight(M_(n))from around 11 to 32 kDa(accordingly denoted as P11k,P18k,P25k,and P32k).When doped in film by FeCl_(3)at the optimized conditions,the maximum power factor(PF_(max))increases greatly from 4.3μW·m^(-1)·K^(-2)for P11k to 8.8μW·m^(-1)·K^(-2)for P18k,and further to 9.7μW·m^(-1)·K^(-2)for P25k,followed by a slight decrease to 9.2μW·m^(-1)·K^(-2)for P32k.The close Seebeck coefficients(S)at PF_(max)are observed in these doped polymer films due to their consistent frontier orbital energy levels and Fermi levels.The main contribution to this PF_(max)evolution thus comes from the corresponding conductivities(σ).Theσvariation of the doped films can be rationally correlated with their microstructure evolution. 展开更多
关键词 conjugated polymer molecular weight MICROSTRUCTURE thermoelectric performance
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qGW11a/OsCAT8,encoding an amino acid permease,negatively regulates grain size and weight in rice
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作者 Peng Gao Feifan Chen +16 位作者 Haitang Liu Shijun Fan Jierui Zeng Xue Diao Yang Liu Wencheng Song Shifu Wang Jing Li Xiaobo Zhu Bin Tu Weilan Chen Ting Li Yuping Wang Bingtian Ma Shigui Li Hua Yuan Peng Qin 《The Crop Journal》 SCIE CSCD 2024年第4期1150-1158,共9页
Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to ... Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent 93-11.Further investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive effect.LOC_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of qGW11a.Overexpression of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain weight.The 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and weight.These results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice. 展开更多
关键词 RICE Grain size Grain weight QTL OsCAT8
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A redundant subspace weighting procedure for clock ensemble
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作者 徐海 陈煜 +1 位作者 刘默驰 王玉琢 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期435-442,共8页
A redundant-subspace-weighting(RSW)-based approach is proposed to enhance the frequency stability on a time scale of a clock ensemble.In this method,multiple overlapping subspaces are constructed in the clock ensemble... A redundant-subspace-weighting(RSW)-based approach is proposed to enhance the frequency stability on a time scale of a clock ensemble.In this method,multiple overlapping subspaces are constructed in the clock ensemble,and the weight of each clock in this ensemble is defined by using the spatial covariance matrix.The superimposition average of covariances in different subspaces reduces the correlations between clocks in the same laboratory to some extent.After optimizing the parameters of this weighting procedure,the frequency stabilities of virtual clock ensembles are significantly improved in most cases. 展开更多
关键词 weighting method redundant subspace clock ensemble time scale
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Curve Classification Based onMean-Variance Feature Weighting and Its Application
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作者 Zewen Zhang Sheng Zhou Chunzheng Cao 《Computers, Materials & Continua》 SCIE EI 2024年第5期2465-2480,共16页
The classification of functional data has drawn much attention in recent years.The main challenge is representing infinite-dimensional functional data by finite-dimensional features while utilizing those features to a... The classification of functional data has drawn much attention in recent years.The main challenge is representing infinite-dimensional functional data by finite-dimensional features while utilizing those features to achieve better classification accuracy.In this paper,we propose a mean-variance-based(MV)feature weighting method for classifying functional data or functional curves.In the feature extraction stage,each sample curve is approximated by B-splines to transfer features to the coefficients of the spline basis.After that,a feature weighting approach based on statistical principles is introduced by comprehensively considering the between-class differences and within-class variations of the coefficients.We also introduce a scaling parameter to adjust the gap between the weights of features.The new feature weighting approach can adaptively enhance noteworthy local features while mitigating the impact of confusing features.The algorithms for feature weighted K-nearest neighbor and support vector machine classifiers are both provided.Moreover,the new approach can be well integrated into existing functional data classifiers,such as the generalized functional linear model and functional linear discriminant analysis,resulting in a more accurate classification.The performance of the mean-variance-based classifiers is evaluated by simulation studies and real data.The results show that the newfeatureweighting approach significantly improves the classification accuracy for complex functional data. 展开更多
关键词 Functional data analysis CLASSIFICATION feature weighting B-SPLINES
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Effects of Functional Organic Materials on Fresh Weight,Quality,Single-melon Weight and SPAD Value of Watermelon
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作者 Kun CHEN Yuefeng ZHAO +5 位作者 Xiaoxue REN Mingda YANG Mingjun ZHAO Yumei WANG Xinhua HUANG Hao LIU 《Agricultural Biotechnology》 2024年第4期54-56,共3页
[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the exper... [Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the experiment,namely four functional organic materials,garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),to investigate the effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon.[Results]The effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon were quite different.The fresh weight,quality,single-melon weight and SPAD value of watermelon were higher in treatment T_(3)applying garlic straw and sheep manure and treatment T_(4)applying onion straw and chicken manure than in treatment T_(1)applying garlic straw and treatment T_(2)applying onion straw.Specifically,the fresh weight of whole plant was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 12.83%and 5.94%respectively compared with treatment T_(1);the weight of single melon was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 42.45%and 31.77%respectively compared with treatment T_(2);and the SPAD values of treatments T_(3)and T_(4)were significantly higher than those of treatments T_(1)and T_(2),and the value of treatment T_(3)was the largest.[Conclusions]This study provides theoretical support for the popularization and application of fertilization techniques combining organic fertilizers and reduced chemical fertilizers for watermelon. 展开更多
关键词 WATERMELON Organic materials Fresh weight QUALITY Single-melon weight SPAD value
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Transcriptomic and metabolomic analysis of changes in grain weight potential induced by water stress in wheat
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作者 Yanmei Gao Maoya Jing +4 位作者 Meng Zhang Zhen Zhang Yuqing Liu Zhimin Wang Yinghua Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3706-3722,共17页
The sink strength of developing ovaries in wheat determines the grain weight potential.The period from booting to the grain setting stage is critical for ovary growth and development and potential sink capacity determ... The sink strength of developing ovaries in wheat determines the grain weight potential.The period from booting to the grain setting stage is critical for ovary growth and development and potential sink capacity determination.However,the underlying regulatory mechanism during this period by which the wheat plant balances and coordinates the floret number and ovary/grain weight under water stress has not been clarified.Therefore,we designed two irrigation treatments of W0(no seasonal irrigation)and W1(additional 75 mm of irrigation at the jointing stage)and analyzed the responses of the ovary/grain weight to water stress at the phenotypic,metabolomic,and transcriptomic levels.The results showed that the W0 irrigation treatment reduced the soil water content,plant height,and green area of the flag leaf,thus reducing grain number,especially for the inferior grains.However,it improved the grain weight of the superior and inferior grains as well as average grain weight at maturity,while the average ovary/grain weight and volume during–3 to 10 days after anthesis(DAA)also increased.Transcriptomic analysis indicated that the genes involved in both sucrose metabolism and phytohormone signal transduction were prominently accelerated by the W0 treatment,accompanied by greater enzymatic activities of soluble acid invertase(SAI)and sucrose synthase(Sus)and elevated abscisic acid(ABA)and indole-3-acetic acid(IAA)levels.Thus,the sucrose content decreased,while the glucose and fructose contents increased.In addition,several TaTPP genes(especially TaTPP-6)were down-regulated and the IAA biosynthesis genes TaTAR1 and TaTAR2 were up-regulated under the W0 treatment before anthesis,which further increased the IAA level.Collectively,water stress reduced the growth of vegetative organs and eliminated most of the inferior grains,but increased the ABA and IAA levels of the surviving ovaries/grains,promoting the enzymatic activity of Sus and degrading sucrose into glucose and fructose.As a result,the strong sucrose utilization ability,the enhanced enzymatic activity of SAI and the ABA-and IAA-mediated signaling jointly increased the weight and volume of the surviving ovaries/grains,and ultimately achieved the tradeoff between ovary/grain weight and number in wheat under water stress. 展开更多
关键词 grain weight sucrose metabolism endogenous hormones water stress transcriptome
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Spatial search weighting information contained in cell velocity distribution
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作者 马一凯 李娜 陈唯 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期522-528,共7页
Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell ... Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication. 展开更多
关键词 cell migration foraging efficiency random walk spatial search weight
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