Weak feature extraction is of great importance for condition monitoring and intelligent diagnosis of aeroengine.Aimed at achieving intelligent diagnosis of aero-engine main shaft bearing,an enhanced sparsity-assisted ...Weak feature extraction is of great importance for condition monitoring and intelligent diagnosis of aeroengine.Aimed at achieving intelligent diagnosis of aero-engine main shaft bearing,an enhanced sparsity-assisted intelligent condition monitoring method is proposed in this paper.Through analyzing the weakness of convex sparse model,i.e.the tradeoff between noise reduction and feature reconstruction,this paper proposes an enhanced-sparsity nonconvex regularized convex model based on Moreau envelope to achieve weak feature extraction.Accordingly,a sparsity-assisted deep convolutional variational autoencoders network is proposed,which achieves the intelligent identification of fault state through training denoised normal data.Finally,the effectiveness of the proposed method is verified through aero-engine bearing run-to-failure experiment.The comparison results show that the proposed method is good at abnormal pattern recognition,showing a good potential for weak fault intelligent diagnosis of aero-engine main shaft bearings.展开更多
The widely expected phase two project of Beijing Star River will open its phase two model units to the public on Oct. 19, and by then Beijing Star River, which has long been regarded as the paradigm of good residence,...The widely expected phase two project of Beijing Star River will open its phase two model units to the public on Oct. 19, and by then Beijing Star River, which has long been regarded as the paradigm of good residence, will unveil its long-awaited phase two offering. The reporter took the lead to pay a visit to the phase two model units recently. The fully innovated phase two products are still ready-made residence, and the quality is even higher.展开更多
The central bank of China has raised her deposit rate for 6 times,and deposit reserve rate for 16 times,since last year up to now,which resulted to a great suffer to those small and medium sized enterprises in finance...The central bank of China has raised her deposit rate for 6 times,and deposit reserve rate for 16 times,since last year up to now,which resulted to a great suffer to those small and medium sized enterprises in finance collection.30 percent of China s small and medium sized enterprises have to be closed down, and 60 percent of them are because of finance problem.How to gather the fund is the biggest obstacle for China's enterprises to grow.展开更多
目的了解蒲公英防治肿瘤相关领域的研究热点与发展趋势。方法检索中国知网、万方数据知识服务平台、维普网及Web of Science核心数据库2000年1月1日—2023年11月24日收录的蒲公英防治肿瘤相关文献,应用CiteSpace软件对作者、发文机构及...目的了解蒲公英防治肿瘤相关领域的研究热点与发展趋势。方法检索中国知网、万方数据知识服务平台、维普网及Web of Science核心数据库2000年1月1日—2023年11月24日收录的蒲公英防治肿瘤相关文献,应用CiteSpace软件对作者、发文机构及关键词进行可视化分析。结果纳入中文文献663篇,英文文献120篇,年发文量呈总体上升趋势。中文文献提取作者698人、机构336个,英文文献提取作者317人、机构189个。提取中文关键词593个,排名前5位的依次为蒲公英、化学成分、乳腺癌、药理作用、用药规律;提取英文关键词337个,排名前5位的依次为apoptosis、dandelion、taraxacum officinale、activation、expression。结论蒲公英防治肿瘤相关研究受到国内外的持续关注,中文文献研究热点为网络药理学、用药规律、数据挖掘等;英文文献研究热点为antioxidant、selective induction、hepatocelluar carcinoma等,总体来说临床研究较少,建议加强基础研究与临床的联系,着力转化研究,充分发掘中药的治疗价值。展开更多
基金the National Natural Science Foundations of China(Nos.91860125,51705398)the National Key Basic Research Program of China(No.2015CB057400)the Shaanxi Province 2020 Natural Science Basic Research Plan(No.2020JQ-042).
文摘Weak feature extraction is of great importance for condition monitoring and intelligent diagnosis of aeroengine.Aimed at achieving intelligent diagnosis of aero-engine main shaft bearing,an enhanced sparsity-assisted intelligent condition monitoring method is proposed in this paper.Through analyzing the weakness of convex sparse model,i.e.the tradeoff between noise reduction and feature reconstruction,this paper proposes an enhanced-sparsity nonconvex regularized convex model based on Moreau envelope to achieve weak feature extraction.Accordingly,a sparsity-assisted deep convolutional variational autoencoders network is proposed,which achieves the intelligent identification of fault state through training denoised normal data.Finally,the effectiveness of the proposed method is verified through aero-engine bearing run-to-failure experiment.The comparison results show that the proposed method is good at abnormal pattern recognition,showing a good potential for weak fault intelligent diagnosis of aero-engine main shaft bearings.
文摘The widely expected phase two project of Beijing Star River will open its phase two model units to the public on Oct. 19, and by then Beijing Star River, which has long been regarded as the paradigm of good residence, will unveil its long-awaited phase two offering. The reporter took the lead to pay a visit to the phase two model units recently. The fully innovated phase two products are still ready-made residence, and the quality is even higher.
文摘The central bank of China has raised her deposit rate for 6 times,and deposit reserve rate for 16 times,since last year up to now,which resulted to a great suffer to those small and medium sized enterprises in finance collection.30 percent of China s small and medium sized enterprises have to be closed down, and 60 percent of them are because of finance problem.How to gather the fund is the biggest obstacle for China's enterprises to grow.
