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Frontiers of Computer Science 2020年第6期14卷 55-69页

作者： Qianchen yu zhiwen yu Zhu WANG Xiaofeng WANG Yongzhi WANG School of Computer Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China Shanxi Provincial Key Laboratory for Embedded System Xi'an 710072China College of Computer Science and Engineering North Minzu UniversityYinchuan 750021China College of Earth Exploration Science and Technology Jilin UniversityChangchun 130025China

Overlapping community detection has become a very hot research topic in recent decades,and a plethora of methods have been ***,a common challenge in many existing overlapping community detection approaches is that the number of communities K must be predefined *** propose a flexible nonparametric Bayesian generative model for count-value networks,which can allow K to increase as more and more data are encountered instead of to be fixed in *** Indian buffet process was used to model the community assignment matrix Z,and an uncol-lapsed Gibbs sampler has been ***,as the community assignment matrix Zis a structured multi-variable parameter,how to summarize the posterior inference results andestimate the inference quality about Z,is still a considerable challenge in the *** this paper,a graph convolutional neural network based graph classifier was utilized to help tosummarize the results and to estimate the inference qualityabout *** conduct extensive experiments on synthetic data and real data,and find that empirically,the traditional posterior summarization strategy is reliable.

关键词： graph convolutional neural network graph classification overlapping community detection nonparametric Bayesian generative model relational infinite latent feature model Indian buffet process uncollapsed Gibbs sampler posterior inference quality estimation

Human-machine interactive streaming anomaly detection by online self-adaptive forest

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Frontiers of Computer Science 2023年第2期17卷 145-156页

作者： Qingyang LI zhiwen yu Huang XU Bin GUO School of Computer Science Northwestern Polytechnical UniversityXi'an 710129China

At nomaly detectors are used to distinguish differences between normal and abnormal data,which are usually implemented by evaluating and ranking the anomaly scores of each instance.A static unsupervised streaming anomaly detector is difficult to dynamically adjust anomaly score *** real scenarios,anomaly detection often needs to be regulated by human feedback,which benefits adjusting anomaly *** this paper,we propose a human-machine interactive streaming anomaly detection method,named ISPForest,which can be adaptively updated online under the guidance of human *** particular,the feedback will be used to adjust the anomaly score calculation and structure of the detector,ideally attaining more accurate anomaly scores in the *** main contribution is to improve the tree-based streaming anomaly detection model that can be updated online from perspectives of anomaly score calculation and model *** approach is instantiated for the powerful class of tree-based streaming anomaly detectors,and we conduct experiments on a range of benchmark *** results demonstrate that the utility of incorporating feedback can improve the performance of anomaly detectors with a few human efforts.

关键词： anomaly detection human-machine interaction human feedback random space tree ensemble method

人工草地建植对三江源区退化高寒草甸土壤有机碳组分的影响

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生态学杂志 2024年第1期43卷 50-56页

作者：李晓燕李永慧秦文萍孙羽马志雯刘翔青海大学省部共建三江源生态与高原农牧业国家重点实验室西宁810016 青海大学生态环境工程学院西宁810016

三江源区高寒草甸的退化正威胁着区域生态安全,如何恢复其土壤有机碳水平是治理该区域退化高寒草甸的关键。本研究以三江源区典型的退化高寒草甸及经其改建而来的人工草地(3年和7年)为对象,运用酸水解法将土壤有机碳库分为活性碳组分I... 详细信息

三江源区高寒草甸的退化正威胁着区域生态安全,如何恢复其土壤有机碳水平是治理该区域退化高寒草甸的关键。本研究以三江源区典型的退化高寒草甸及经其改建而来的人工草地(3年和7年)为对象,运用酸水解法将土壤有机碳库分为活性碳组分I、活性碳组分II和惰性碳组分,定量评估人工草地建植后土壤有机碳组分及其生物化学稳定性的变化特征。结果表明:各类样地土壤有机碳组分含量按照惰性碳组分、活性碳组分I和活性碳组分II的顺序依次递减,表明惰性碳组分是土壤有机碳库的主要构成部分;在建植人工草地3年后,0~30 cm土层的总有机碳、活性碳组分I和惰性碳组分含量均未发生显著变化,而活性碳组分II含量出现显著下降(P<0.05);相比之下,建植人工草地7年后,除土壤活性碳组分II含量未发生显著变化外,总有机碳和其他碳组分含量均呈现出增加的变化趋势;退化高寒草甸、建植3年和建植7年人工草地的土壤有机碳惰性指数分别为43.7%~48.4%、42.3%~48.9%和42.3%~53.4%,尽管建植7年人工草地的土壤有机碳惰性指数要高于其他两类样地,但仅在10~20 cm土层表现为显著差异(P<0.05)。综上表明,长时间的人工植被恢复有助于提升三江源区退化高寒草甸土壤有机碳含量及其生物化学稳定性,促进土壤碳汇功能的恢复。

关键词：有机碳组分生物化学稳定性人工草地生态恢复

Erratum to:Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance

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Nano Research 2024年第6期17卷 5760-5760页

作者： zhiwen Li Liangliang Xu Zaheer UdDin Babar Ali Raza Yifei Zhang Xinrui Gu yu-Xin Miao Zhen Zhao Gao Li Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Scuola Superiore Meridionale(SSM) University of Naples Federico IILargo S.Marcellino1080138Italy Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea University of Chinese Academy of Sciences Beijing 100049China

In the first page of the original version of this paper,the Received date should be“9 October 2023”instead of“9 October 2013”.

关键词： performance (2)

Relative manifold based semi-supervised dimensionality reduction

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Frontiers of Computer Science 2014年第6期8卷 923-932页

作者： Xianfa CAI Guihua WEN Jia WEI zhiwen yu School of Medical Information Engineering Guangdong Pharmaceutical University Guangzhou 510006 China School of Computer Science and Engineering South China University of Technology Guangzhou 510006 China Shenzhen Key Laboratory of High Performance Data Mining Shenzhen 518055 China

A well-designed graph plays a fundamental role in graph-based semi-supervised learning; however, the topological structure of a constructed neighborhood is unstable in most current approaches, since they are very sensitive to the high dimensional, sparse and noisy data. This generally leads to dramatic performance degradation. To deal with this issue, we developed a relative manifold based semisupervised dimensionality reduction （RMSSDR） approach by utilizing the relative manifold to construct a better neighborhood graph with fewer short-circuit edges. Based on the relative cognitive law and manifold distance, a relative transformation is used to construct the relative space and the relative manifold. A relative transformation can improve the ability to distinguish between data points and reduce the impact of noise such that it may be more intuitive, and the relative manifold can more truly reflect the manifold structure since data sets commonly exist in a nonlinear structure. Specifically, RMSSDR makes full use of pairwise constraints that can define the edge weights of the neighborhood graph by minimizing the local reconstruction error and can preserve the global and local geometric structures of the data set. The experimental results on face data sets demonstrate that RMSSDR is better than the current state of the art comparing methods in both performance of classification and robustness.

关键词： cognitive law relative transformation relative manifold local reconstruction semi-supervised learning

Mobile crowd photographing: another way to watch our world

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Science China(Information Sciences) 2016年第8期59卷 250-274页

作者： Huihui CHEN Bin GUO zhiwen yu Xingshe ZHOU School of Computer Science Northwestern Polytechnical University School of Computer and Information Engineering Luoyang Institute of Science and Technology

People take and share pictures in the mobile network. Through collecting and computing pictures with built-in contexts, Mobile Crowd Photographing(MCP) can give us a new way to see this world. This paper focuses on participatory picture collection, which is one way of MCP. Three characteristic issues of MCP are proposed, and then our recent work to solve these issues will also be demonstrated.

关键词： mobile crowd photographing task-driven data collection task definition task assignment data selection

甘蓝型油菜转录因子BnHY5-2参与盐碱胁迫的响应

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华北农学报 2024年第4期39卷 47-53页

作者：杨明煊李明玉汪波王泽刘智强周广生于放刘志文大连工业大学生物工程学院辽宁大连116034 农业农村部长江中游作物生理生态与耕作重点实验室华中农业大学植物科学技术学院湖北武汉430070 大连市农业科学研究院辽宁大连116036

转录因子BnHY5-2与植物抗逆性相关。为揭示甘蓝型油菜转录因子BnHY5-2对盐碱胁迫的响应,主要通过瞬时转化过表达、qRT-PCR分析、亚细胞定位等方法,分析甘蓝型油菜转录因子BnHY5-2对光和盐碱的响应。结果表明,光照处理油菜后,在叶与茎中B... 详细信息

转录因子BnHY5-2与植物抗逆性相关。为揭示甘蓝型油菜转录因子BnHY5-2对盐碱胁迫的响应,主要通过瞬时转化过表达、qRT-PCR分析、亚细胞定位等方法,分析甘蓝型油菜转录因子BnHY5-2对光和盐碱的响应。结果表明,光照处理油菜后,在叶与茎中BnHY5-2基因的表达量均显著高于黑暗条件下,分别为黑暗条件下的29.22,3.15倍,叶片对光的敏感性大于茎,说明叶片是响应光转录因子BnHY5-2的主要部位。在光照条件下应用大连滨海盐碱土种植油菜,处理后BnHY5-2的表达在叶和茎中均显著下调,分别下调53.1%,31.0%;在黑暗条件下应用盐碱处理后BnHY5-2的表达在茎中下调48.2%,而在叶中的表达差异则不显著,表现出器官的差异性,说明叶片对光照条件要求更加严格。在油菜叶片中瞬时过表达BnHY5-2基因时,6个与盐碱相关的候选基因的表达中,有2个(BnNAC32、BnGS)上调表达,分别为原来的1.25,3.28倍;而有4个(Bnamy、BnAsp、BnNHX7、BnTPS)下调表达,分别下降24.8%,25.4%,71.0%,82.0%,同时甜菜碱含量由0.256 mg/g提升至0.573 mg/g,提高了1.24倍,说明过表达BnHY5-2基因会提高油菜的盐碱抗性。亚细胞定位结果显示,转录因子BnHY5-2定位于细胞核中,调控功能基因的表达。因此,BnHY5-2不仅与光信号有关,还参与油菜盐碱抗性。

关键词：甘蓝型油菜 BnHY5-2 盐碱胁迫过表达转录因子

Sphere decoder for polar codes concatenated with cyclic redundancy check

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Science China(Information Sciences) 2019年第8期62卷 159-171页

作者： Yongrun yu zhiwen PAN Nan LIU Xiaosi TAN National Mobile Communications Research Laboratory Southeast University

The existing cyclic redundancy check(CRC)-aided successive cancellation list(CA-SCL) decoder partitions the decoding process into two steps, where an SCL is followed by a CRC check. An SCL decoder can approach the maximum-likelihood(ML) decoding performance of the inner polar codes using a sufficiently large list; however, in this case, CRC is only used for performing error detection. Therefore, the decoding performance of the outer CRC is different from that of ML because the errors are not rectified, which degrades the performance of the entire concatenated codes. In this study, we propose a sphere decoder(SD) that can achieve the ML performance of polar codes concatenated with CRC to address the suboptimality of CASCL decoding. The proposed SD performs joint decoding of the CRC-polar codes in a single step, thereby avoiding the polar decoding and CRC detection decoding scheme. Because the proposed SD guarantees the ML decoding performance of the CRC-polar concatenated codes, the simulation results demonstrate that the block error rate(BLER) of the proposed SD acts as the lower bound of the CA-SCL decoding performance. Further, a new initial radius selection method is proposed for the SD to reduce the average decoding complexity. The simulations demonstrate that the proposed initial radius selection method reduces more amount of decoding complexity when compared with that reduced using sequential step size methods.

关键词： polar codes sphere decoder maximum-likelihood decoding optimal decoding radius search

A framework based on sparse representation model for time series prediction in smart city

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Frontiers of Computer Science 2021年第1期15卷 99-111页

作者： Zhiyong yu Xiangping ZHENG Fangwan HUANG Wenzhong GUO Lin SUN zhiwen yu College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China Hangzhou Key Laboratory for IoT Technology&Application Zhejiang University City CollegeHangzhou 310015China School of Computer Science Northwestern Polytechnical UniversityXi’an 710072China

Smart city driven by Big Data and Internet of Things(loT)has become a most promising trend of the *** one important function of smart city,event alert based on time series prediction is faced with the challenge of how to extract and represent discriminative features of sensing knowledge from the massive sequential data generated by IoT *** this paper,a framework based on sparse representa-tion model(SRM)for time series prediction is proposed as an efficient approach to tackle this *** dividing the over-complete dictionary into upper and lower parts,the main idea of SRM is to obtain the sparse representation of time series based on the upper part firstly,and then realize the prediction of future values based on the lower *** choice of different dictionaries has a significant impact on the performance of *** paper focuses on the study of dictionary construction strategy and summarizes eight variants of *** results demonstrate that SRM can deal with different types of time series prediction flexibly and effectively.

关键词： sparse representation smart city time series prediction dictionary construction

A survey on ensemble learning

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Frontiers of Computer Science 2020年第2期14卷 241-258页

作者： Xibin DONG zhiwen yu Wenming CAO Yifan SHI Qianli MA School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Department of Computer Science City University of Hong KongHong Kong SAR 999077China

Despite significant successes achieved in knowledge discovery,traditional machine learning methods may fail to obtain satisfactory performances when dealing with complex data,such as imbalanced,high-dimensional,noisy data,*** reason behind is that it is difficult for these methods to capture multiple characteristics and underlying structure of *** this context,it becomes an important topic in the data mining field that how to effectively construct an efficient knowledge discovery and mining *** learning,as one research hot spot,aims to integrate data fusion,data modeling,and data mining into a unified ***,ensemble learning firstly extracts a set of features with a variety of *** on these learned features,multiple learning algorithms are utilized to produce weak predictive ***,ensemble learning fuses the informative knowledge from the above results obtained to achieve knowledge discovery and better predictive performance via voting schemes in an adaptive *** this paper,we review the research progress of the mainstream approaches of ensemble learning and classify them based on different *** addition,we present challenges and possible research directions for each mainstream approach of ensemble learning,and we also give an extra introduction for the combination of ensemble learning with other machine learning hot spots such as deep learning,reinforcement learning,etc.

关键词： ensemble learning supervised ensemble classification semi-supervised ensemble classification clustering ensemble semi-supervised clustering ensemble