It is not uncommon for malicious sellers to collude with fake reviewers(also called spammers)to write fake reviews for multiple products to either demote competitors or promote their products'reputations,forming a...It is not uncommon for malicious sellers to collude with fake reviewers(also called spammers)to write fake reviews for multiple products to either demote competitors or promote their products'reputations,forming a gray industry chain.To detect spammer groups in a heterogeneous network with rich semantic information from both buyers and sellers,researchers have conducted extensive research using Frequent Item Mining-based and graph-based meth-ods.However,these methods cannot detect spammer groups with cross-product attacks and do not jointly consider structural and attribute features,and structure-attribute correlation,resulting in poorer detection performance.There-fore,we propose a collaborative training-based spammer group detection algorithm by constructing a heterogene-ous induced sub-network based on the target product set to detect cross-product attack spammer groups.To jointly consider all available features,we use the collaborative training method to learn the feature representations of nodes.In addition,we use the DBSCAN clustering method to generate candidate groups,exclude innocent ones,and rank them to obtain spammer groups.The experimental results on real-world datasets indicate that the overall detection performance of the proposed method is better than that of the baseline methods.展开更多
Yellowing is one of the main problems of quality deterioration in the storage,transportation,and sales of post-harvested broccoli,which seriously affects the commodity value of broccoli.Therefore,it is of significance...Yellowing is one of the main problems of quality deterioration in the storage,transportation,and sales of post-harvested broccoli,which seriously affects the commodity value of broccoli.Therefore,it is of significance to understand the mechanism of the process and develop effective regulation technology.In this review,we expounded the changes in the appearance of the flower ball,bud morphology,and calyx cell structure,as well as endogenous pigment metabolism,accompanying the yellowing process of broccoli.In addition,recent research on the molecular mechanism of yellowing was summarized from the aspects of transcriptome analysis and transcription regulation.Finally,the progress on the control technology of broccoli yellowing was reviewed.展开更多
基金This paper is supported in part by the Natural Science Foundation of China(No.71772107,62072288)Shandong Nature Science Foundation of China[Grant No.ZR2019MF003,ZR2020MF044].
文摘It is not uncommon for malicious sellers to collude with fake reviewers(also called spammers)to write fake reviews for multiple products to either demote competitors or promote their products'reputations,forming a gray industry chain.To detect spammer groups in a heterogeneous network with rich semantic information from both buyers and sellers,researchers have conducted extensive research using Frequent Item Mining-based and graph-based meth-ods.However,these methods cannot detect spammer groups with cross-product attacks and do not jointly consider structural and attribute features,and structure-attribute correlation,resulting in poorer detection performance.There-fore,we propose a collaborative training-based spammer group detection algorithm by constructing a heterogene-ous induced sub-network based on the target product set to detect cross-product attack spammer groups.To jointly consider all available features,we use the collaborative training method to learn the feature representations of nodes.In addition,we use the DBSCAN clustering method to generate candidate groups,exclude innocent ones,and rank them to obtain spammer groups.The experimental results on real-world datasets indicate that the overall detection performance of the proposed method is better than that of the baseline methods.
基金This work was supported by the National Key Research and Development Program of China(No.2016YFD0400103).
文摘Yellowing is one of the main problems of quality deterioration in the storage,transportation,and sales of post-harvested broccoli,which seriously affects the commodity value of broccoli.Therefore,it is of significance to understand the mechanism of the process and develop effective regulation technology.In this review,we expounded the changes in the appearance of the flower ball,bud morphology,and calyx cell structure,as well as endogenous pigment metabolism,accompanying the yellowing process of broccoli.In addition,recent research on the molecular mechanism of yellowing was summarized from the aspects of transcriptome analysis and transcription regulation.Finally,the progress on the control technology of broccoli yellowing was reviewed.
