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Expeditionplus:The application of a gridded system in the integration of multidimensional environmental factors
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作者 Xinyuan Kuai Quansheng Fu +1 位作者 Hang Sun Tao Deng 《Plant Diversity》 2025年第4期702-708,共7页
The study of plant diversity is often hindered by the challenge of integrating data from different sources and different data types.A standardized data system would facilitate detailed exploration of plant distributio... The study of plant diversity is often hindered by the challenge of integrating data from different sources and different data types.A standardized data system would facilitate detailed exploration of plant distribution patterns and dynamics for botanists,ecologists,conservation biologists,and biogeographers.This study proposes a gridded vector data integration method,combining grid-based techniques with vectorization to integrate diverse data types from multiple sources into grids of the same scale.Here we demonstrate the methodology by creating a comprehensive 1°×1°database of western China that includes plant distribution information and environmental factor data.This approach addresses the need for a standardized data system to facilitate exploration of plant distribution patterns and dynamic changes in the region. 展开更多
关键词 Gridded system data integration multidimensional environmental factors Western China GIS Plant distribution
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Multidimensional Visualization of Bikeshare Travel Patterns Using a Visual Data Mining Technique: Data Cubes
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作者 Xinwei Ma Yanjie Ji +2 位作者 Yang Liu Yuchuan Jin Chenyu Yi 《Journal of Beijing Institute of Technology》 EI CAS 2019年第2期265-277,共13页
In order to explore the travel characteristics and space-time distribution of different groups of bikeshare users,an online analytical processing(OLAP)tool called data cube was used for treating and displaying multi-d... In order to explore the travel characteristics and space-time distribution of different groups of bikeshare users,an online analytical processing(OLAP)tool called data cube was used for treating and displaying multi-dimensional data.We extended and modified the traditionally threedimensional data cube into four dimensions,which are space,date,time,and user,each with a user-specified hierarchy,and took transaction numbers and travel time as two quantitative measures.The results suggest that there are two obvious transaction peaks during the morning and afternoon rush hours on weekdays,while the volume at weekends has an approximate even distribution.Bad weather condition significantly restricts the bikeshare usage.Besides,seamless smartcard users generally take a longer trip than exclusive smartcard users;and non-native users ride faster than native users.These findings not only support the applicability and efficiency of data cube in the field of visualizing massive smartcard data,but also raise equity concerns among bikeshare users with different demographic backgrounds. 展开更多
关键词 bikeshare smartcard data TRAVEL PATTERN multidimensional VISUALIZATION
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Approach to conceptual data integration for multidimensional data analysis in e-commerce
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作者 Zhang Zhe Huang Pei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期635-641,共7页
In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to mul... In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to multidimensional data model the UML galaxy diagram is presented in order to conduct multidimensional data analysis for multiple subjects. The approach is illuminated using a case of 2_roots UML galaxy diagram that takes marketing analysis of TV products involved one retailer and several suppliers into consideration. 展开更多
关键词 conceptual data integration multidimensional data analysis E-COMMERCE
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Constructing a data platform for surface defect management using a multidimensional database
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作者 SU Yicai OU Peng GAO Wenwu 《Baosteel Technical Research》 CAS 2013年第4期16-20,共5页
Surface quality has been one of the key factors influencing the ongoing improvement of the quality of steel. Therefore,it is urgent to provide methods for efficient supervision of surface defects. This paper first exp... Surface quality has been one of the key factors influencing the ongoing improvement of the quality of steel. Therefore,it is urgent to provide methods for efficient supervision of surface defects. This paper first expressed the main problems existing in defect management and then focused on constructing a data platform of surface defect management using a multidimensional database. Finally, some onqine applications of the platform at Baosteel were demonstrated. Results show that the constructed multidimensional database provides more structured defect data, and thus it is suitable for swift and multi-angle analysis of the defect data. 展开更多
关键词 surface defect multidimensional database data warehouse on-line analysis
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Buildings and terrain unified-multidimensional dual data structure for GIS
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作者 Pawel BOGUSLAWSKI Christopher GOLD 《Geo-Spatial Information Science》 SCIE EI CSCD 2015年第4期151-158,共8页
3D city models are widely used in many disciplines and applications,such as urban planning,disaster management,and environmental simulation.Usually,the terrain and embedded objects like buildings are taken into consid... 3D city models are widely used in many disciplines and applications,such as urban planning,disaster management,and environmental simulation.Usually,the terrain and embedded objects like buildings are taken into consideration.A consistent model integrating these elements is vital for GIS analysis,especially if the geometry is accompanied by the topological relations between neighboring objects.Such a model allows for more efficient and errorless analysis.The memory consumption is another crucial aspect when the wide area of a city is considered-light models are highly desirable.Three methods of the terrain representation using the geometrical-topological data structure-the dual half-edge-are proposed in this article.The integration of buildings and other structures like bridges with the terrain is also presented. 展开更多
关键词 multidimensional modeling GIS data structures
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Geo-Scape,a Granularity Depended Spatialization Tool for Visualizing Multidimensional Data Sets
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作者 Kontaxaki Sofia Kokla Margarita Kavouras Marinos 《Geo-Spatial Information Science》 2010年第4期275-284,共10页
Recently,the expertise accumulated in the field of geovisualization has found application in the visualization of abstract multidimensional data,on the basis of methods called spatialization methods.Spatialization met... Recently,the expertise accumulated in the field of geovisualization has found application in the visualization of abstract multidimensional data,on the basis of methods called spatialization methods.Spatialization methods aim at visualizing multidimensional data into low-dimensional representational spaces by making use of spatial metaphors and applying dimension reduction techniques.Spatial metaphors are able to provide a metaphoric framework for the visualization of information at different levels of granularity.The present paper makes an investigation on how the issue of granularity is handled in the context of representative examples of spatialization methods.Furthermore,this paper introduces the prototyping tool Geo-Scape,which provides an interactive spatialization environment for representing and exploring multidimensional data at different levels of granularity,by making use of a kernel density estimation technique and on the landscape "smoothness" metaphor.A demonstration scenario is presented next to show how Geo-Scape helps to discover knowledge into a large set of data,by grouping them into meaningful clusters on the basis of a similarity measure and organizing them at different levels of granularity. 展开更多
关键词 multidimensional data spatial metaphors SPATIALIZATION graphical interface kernel density estimation
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Multidimensional Design Paradigms for Data Warehouses: A Systematic Mapping Study
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作者 Ania Cravero Samuel Sepúlveda 《Journal of Software Engineering and Applications》 2014年第1期53-61,共9页
Data warehouses (DW) must integrate information from the different areas and sources of an organization in order to extract knowledge relevant to decision-making. The DW development is not an easy task, which is why v... Data warehouses (DW) must integrate information from the different areas and sources of an organization in order to extract knowledge relevant to decision-making. The DW development is not an easy task, which is why various design approaches have been put forward. These approaches can be classified in three different paradigms according to the origin of the information requirements: supply-driven, demand-driven, and hybrids of these. This article compares the methodologies for the multidimensional design of DW through a systematic mapping as research methodology. The study is presented for each paradigm, the main characteristics of the methodologies, their notations and problem areas exhibited in each one of them. The results indicate that there is no follow-up to the complete process of implementing a DW in either an academic or industrial environment;however, there is also no evidence that the attempt is made to address the design and development of a DW by applying and comparing different methodologies existing in the field. 展开更多
关键词 multidimensional DESIGN Paradigms data Warehouses Systematic MAPPING
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Research on Multidimensional Data Model in Data Warehouse
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作者 Guangjie LI 《International Journal of Technology Management》 2015年第1期120-122,共3页
Data structure and semantics of the traditional data model cannot effectively represent the data warehouse, it is difficult to effectively support online analytical processing (referred to as OLAP). This paper is pr... Data structure and semantics of the traditional data model cannot effectively represent the data warehouse, it is difficult to effectively support online analytical processing (referred to as OLAP). This paper is propose a new multidimensional data model based on the partial ordering and mapping. The data model can fully express the complex data structure and semantics of data warehouse, and provide an OLAP operation as the core of the operation of algebra, support structure in levels of complex aggregation operation sequence, which can effectively support the application of OLAE The data model supports the concept of aggregation function constraint, and provides constraint mechanism of the hierarchy aggregation function. 展开更多
关键词 data warehouse data model multidimensional data model OLAP
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Applying XML for designing and interchanging information for multidimensional model 被引量:2
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作者 Lu Changhui Deng Su Zhang Weiming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期823-830,共8页
In order to exchange and share information among the conceptual models of data warehouse, and to build a solid base for the integration and share of metadata, a new multidimensional concept model is presented based on... In order to exchange and share information among the conceptual models of data warehouse, and to build a solid base for the integration and share of metadata, a new multidimensional concept model is presented based on XML and its DTD is defined, which can perfectly describe various semantic characteristics of multidimensional conceptual model. According to the multidimensional conceptual modeling technique which is based on UML, the mapping algorithm between the multidimensional conceptual model is described based on XML and UML class diagram, and an application base for the wide use of this technique is given. 展开更多
关键词 data warehouse OLAP multidimensional modeling conceptual model XML UML.
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Investigating poverty in rural Iran: The multidimensional poverty approach 被引量:1
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作者 Abdolrasul Shirvanian Mohammad Bakhshoodeh 《Agricultural Sciences》 2012年第5期640-650,共11页
In this study, rural poverty in Iran is investigated applying a multidimensional approach, association rules mining technique, and Levine, F and Tukey tests to household data of 2008. The results indicate that poverty... In this study, rural poverty in Iran is investigated applying a multidimensional approach, association rules mining technique, and Levine, F and Tukey tests to household data of 2008. The results indicate that poverty in its multi-dimensions is an epidemic problem in rural Iran. The results also exhibit that there are 11 patterns of poverty in the rural areas including four main patterns with 99.62% coverage and seven sub-patterns with nearly 0.38% coverage. In these patterns, housing and household education are the most important dimensions of poverty and income poverty is the least important dimension. Government income support policy to households, in enforcement the law of targeting subsidies, cannot be regarded as pro poor policy but it follows other political aspects. 展开更多
关键词 multidimensional POVERTY APPROACH RURAL POVERTY data MINING Iran
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Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates 被引量:1
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作者 Héber H.Arcolezi Jean-François Couchot +1 位作者 Bechara Al Bouna Xiaokui Xiao 《Digital Communications and Networks》 SCIE CSCD 2024年第2期369-379,共11页
This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)guarantees.Contra... This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)guarantees.Contrary to frequency estimation of a single attribute,the multidimensional aspect demands particular attention to the privacy budget.Besides,when collecting user statistics longitudinally,privacy progressively degrades.Indeed,the“multiple”settings in combination(i.e.,many attributes and several collections throughout time)impose several challenges,for which this paper proposes the first solution for frequency estimates under LDP.To tackle these issues,we extend the analysis of three state-of-the-art LDP protocols(Generalized Randomized Response–GRR,Optimized Unary Encoding–OUE,and Symmetric Unary Encoding–SUE)for both longitudinal and multidimensional data collections.While the known literature uses OUE and SUE for two rounds of sanitization(a.k.a.memoization),i.e.,L-OUE and L-SUE,respectively,we analytically and experimentally show that starting with OUE and then with SUE provides higher data utility(i.e.,L-OSUE).Also,for attributes with small domain sizes,we propose Longitudinal GRR(L-GRR),which provides higher utility than the other protocols based on unary encoding.Last,we also propose a new solution named Adaptive LDP for LOngitudinal and Multidimensional FREquency Estimates(ALLOMFREE),which randomly samples a single attribute to be sent with the whole privacy budget and adaptively selects the optimal protocol,i.e.,either L-GRR or L-OSUE.As shown in the results,ALLOMFREE consistently and considerably outperforms the state-of-the-art L-SUE and L-OUE protocols in the quality of the frequency estimates. 展开更多
关键词 Local differential privacy Discrete distribution estimation Frequency estimation multidimensional data Longitudinal studies
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Construction and Application of the Multidimensional Table for Knowledge Discovery in Ancient Chinese Books on Materia Medica 被引量:1
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作者 Rui Jin Qian Lin +2 位作者 Jun Zhou Boyu Sun Bing Zhang 《Engineering(科研)》 2013年第10期1-6,共6页
Knowledge discovery, as an increasingly adopted information technology in biomedical science, has shown great promise in the field of Traditional Chinese Medicine (TCM). In this paper, we provided a kind of multidimen... Knowledge discovery, as an increasingly adopted information technology in biomedical science, has shown great promise in the field of Traditional Chinese Medicine (TCM). In this paper, we provided a kind of multidimensional table which was well suited for organizing and analyzing the data in ancient Chinese books on Materia Medica. Moreover, we demonstrated its capability of facilitating further mining works in TCM through two illustrative studies of discovering meaningful patterns in the three-dimensional table of Shennong’s Classic of Materia Medica. This work might provide an appropriate data model for the development of knowledge discovery in TCM. 展开更多
关键词 multidimensional TABLE TCM HERBAL Medicine data Mining Knowledge DISCOVERY
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Design of Multichannel Adaptive Filter by Constructing Multidimensional Wiener-Hopf Equation
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作者 Zhisong Hao Chaoyu He +1 位作者 Min Jia Leilei Wu 《China Communications》 SCIE CSCD 2022年第7期124-134,共11页
In the satellite-to-ground high-speed data transmission link,there are signal self-interference problems of symbols in the co-channel,as well as between orthogonal and polarized channels.A multichannel adaptive filter... In the satellite-to-ground high-speed data transmission link,there are signal self-interference problems of symbols in the co-channel,as well as between orthogonal and polarized channels.A multichannel adaptive filter is designed by constructing a multichannel Wiener-Hopf equation,and the influence of five channel nonideal factors is suppressed to improve the BER performance.Experiments show that this method is effective to suppress the signal selfinterference,and the BER floor is optimized from 1E3 to 1E-7. 展开更多
关键词 satellite-ground data transmission link symbol self-interference multidimensional WienerHopf equation
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混合式教学“全程多维数据驱动”评价体系实证研究
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作者 崔媛媛 常远 +3 位作者 郑慧媛 邱忠营 张玉洁 苏兴利 《医学教育研究与实践》 2026年第2期198-203,共6页
目的构建并验证混合式教学“全程多维数据驱动”评价体系的科学性和有效性。方法采用平行对照实验设计,将116名临床医学专业大一学生随机分为实验组(n=58)与对照组(n=58)。实验组采用“全程多维数据驱动”评价,对照组沿用传统教学评价... 目的构建并验证混合式教学“全程多维数据驱动”评价体系的科学性和有效性。方法采用平行对照实验设计,将116名临床医学专业大一学生随机分为实验组(n=58)与对照组(n=58)。实验组采用“全程多维数据驱动”评价,对照组沿用传统教学评价。结果两组期末实验考试成绩有显著差异,且消除“马太效应”;实验组知识掌握更均衡,学习自主性提高明显。结论“全程多维数据驱动”评价体系能通过“评价-反馈-优化”闭环实现教学相长,突破传统教学评价局限,为混合式教学改革提供实证支持。 展开更多
关键词 混合式教学 教学评价 多维数据驱动
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多维玻璃存储的机遇与挑战
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作者 张静宇 肖哲翔 +4 位作者 闫玉玺 胡景淇 刘艳霞 王海卫 高骥超 《计算机工程与设计》 北大核心 2026年第3期619-630,共12页
在大数据时代信息量快速增长的背景下,数据存储在容量、能耗与长期稳定性方面面临着挑战。多维玻璃光存储作为一种新型数据存储技术,因其超高存储密度、长期保存能力及环境稳定性而受到广泛关注。围绕多维玻璃存储的发展历程,从激光与... 在大数据时代信息量快速增长的背景下,数据存储在容量、能耗与长期稳定性方面面临着挑战。多维玻璃光存储作为一种新型数据存储技术,因其超高存储密度、长期保存能力及环境稳定性而受到广泛关注。围绕多维玻璃存储的发展历程,从激光与玻璃材料相互作用机理出发,总结了近年来基于量子点、周期性纳米结构、非周期性各向异性纳米结构的玻璃光存储所取得的成果。在此基础上,对多维玻璃存储所面临的问题与挑战进行了分析,并展望了其在高可靠、超长寿命数据存储领域的发展前景。 展开更多
关键词 大数据 多维光存储 玻璃光存储 激光与玻璃相互作用 量子点 周期性纳米结构 各向异性纳米结构 数据存储
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车路协同系统中车载真值系统测试方法研究
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作者 王德利 李连福 +1 位作者 张蔚 蒋鑫 《汽车工程》 北大核心 2026年第2期274-281,共8页
针对车路协同系统中车载真值系统及其感知目标精度难以量化评估的问题,在调研了当前车路协同系统主流组成模块的基础上,针对多种传感器采集的不同类型数据,提出了一种基于多维数据量值溯源测试方法,并在中国计量科学研究院GNSS接收机检... 针对车路协同系统中车载真值系统及其感知目标精度难以量化评估的问题,在调研了当前车路协同系统主流组成模块的基础上,针对多种传感器采集的不同类型数据,提出了一种基于多维数据量值溯源测试方法,并在中国计量科学研究院GNSS接收机检测场进行了实验测试。结果表明,车载真值系统在车辆加减速以及转弯运动过程中,速度与平面位置均出现较大误差,说明该系统算法仍须改进和优化,在近匀速直线运动中速度误差平均值为0.02 m/s,航向角误差平均值0.07°,平面位置误差平均值0.06 m,3项指标均满足测试大纲中技术要求。最后,通过车载真值系统对行人、非机动车和机动车的速度、航向角和平面位置的感知测试,验证了多维数据感知融合算法以及不同目标建模的准确性。通过对多维数据的分类提取处理,使其均可溯源至国家基准或标准,这对车路协同系统中车载真值系统获取数据准确性的评估具有重要借鉴意义。 展开更多
关键词 车路协同 车载真值系统 感知融合 速度 航向角 平面位置 多维数据
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基于反事实数据增强的高价值专利识别模型
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作者 成伟 余传明 《情报杂志》 北大核心 2026年第3期104-115,共12页
[目的]解决当前高价值专利识别模型过度依赖历史统计数据,缺乏因果解释力的问题,提升高价值专利识别的效果与可解释性。[方法]提出了一种基于反事实数据增强的高价值专利识别模型,该模型构建多类型节点的异构图,融合GAT与GCN捕获节点关... [目的]解决当前高价值专利识别模型过度依赖历史统计数据,缺乏因果解释力的问题,提升高价值专利识别的效果与可解释性。[方法]提出了一种基于反事实数据增强的高价值专利识别模型,该模型构建多类型节点的异构图,融合GAT与GCN捕获节点关系,通过对抗神经网络对节点特征扰动生成反事实样本,并利用增量学习策略实现专利价值评估与因果机制揭示。[结果/结论]实验结果表明,本文模型在人工智能领域专利数据集中的准确率、精确率、召回率、F1值分别达到了84.27%、84.51%、85.17%、84.84%,优于基线模型,证明了本文方法的有效性,为高价值专利识别任务提供了新的研究视角。 展开更多
关键词 高价值专利识别 反事实数据增强 图神经网络 对抗神经网络 多维特征 增量学习
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面向时序数据的多维度网络舆情演化分析研究
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作者 李旸 王志华 +3 位作者 李大宇 赵鑫 詹雅慧 王素格 《大数据》 2026年第1期29-42,共14页
针对当前网络舆情演化研究存在的视角单一、主题挖掘不全、情感分析不深、群体行为发现不准等局限,提出了一项多维度网络舆情演化分析框架。首先,依据社会影响力,划分了舆情演化的4个生命周期阶段。其次,基于BERTopic模型和相似性计算... 针对当前网络舆情演化研究存在的视角单一、主题挖掘不全、情感分析不深、群体行为发现不准等局限,提出了一项多维度网络舆情演化分析框架。首先,依据社会影响力,划分了舆情演化的4个生命周期阶段。其次,基于BERTopic模型和相似性计算分析了主题演化过程,利用大语言模型分析了情感波动,基于交互关系划分了用户群体并识别了意见领袖。最后,对不同周期和地域的社会影响力与情感差异进行了可视化呈现。以时序舆情数据中“印花税调整”事件为例,研究发现在舆情的4个生命周期,民众关注的话题、情感倾向、用户群体以及意见领袖均发生了变化,东部地区对“印花税调整”事件的情感反应更积极,且舆情主题和情感持续时间更长。该研究可为揭示舆情演化规律、实施有效舆情监控提供技术支持。 展开更多
关键词 时序数据 网络舆情 多维度演化 主题演化 情感波动 用户群体
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基于多维视图追踪的内核Rootkit检测方法
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作者 郑伊健 李勇钢 《计算机工程》 北大核心 2026年第3期177-189,共13页
在Linux服务器中,内核Rootkit因其高隐蔽性和高特权性,可长时间潜伏在操作系统中,对内核造成严重破坏,尤其是未知Rootkit,其攻击发生时间和空间分布都是随机的,这为发现攻击源头带来严峻挑战。由于源码是未知的,常规方法难以分析其行为... 在Linux服务器中,内核Rootkit因其高隐蔽性和高特权性,可长时间潜伏在操作系统中,对内核造成严重破坏,尤其是未知Rootkit,其攻击发生时间和空间分布都是随机的,这为发现攻击源头带来严峻挑战。由于源码是未知的,常规方法难以分析其行为特征,也无法在合适的位置预设检测点。为了应对这一威胁,提出一种基于多维视图追踪的内核Rootkit检测方法。通过在空间维度和时间维度上对多个视图进行交叉对比,可检测未知内核Rootkit的恶意行为,并还原被隐藏的数据。实验和分析显示,该方法对内核Rootkit具有良好的检测效果,在安全响应周期为0.1 s的情况下,该方法引入的CPU开销仅为0.38%。 展开更多
关键词 内核Rootkit Linux服务器安全 多维视图追踪 隐藏检测 还原隐藏数据
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人工智能领域前沿主题的多维指标识别与动态演化分析
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作者 胡泽文 韩雅蓉 +1 位作者 张欣雨 刘畅 《图书馆论坛》 北大核心 2026年第4期74-91,共18页
文章聚焦论文、基金和专利等多源数据,构建前沿主题挖掘指标体系和BERT-LDA模型。研究发现,面向多源数据的前沿主题识别指标体系能有效识别领域前沿主题,为数据驱动的前沿主题定量识别提供指导。总体看,多源数据视角下的人工智能领域前... 文章聚焦论文、基金和专利等多源数据,构建前沿主题挖掘指标体系和BERT-LDA模型。研究发现,面向多源数据的前沿主题识别指标体系能有效识别领域前沿主题,为数据驱动的前沿主题定量识别提供指导。总体看,多源数据视角下的人工智能领域前沿主题涵盖机器学习与深度学习、自然语言处理、计算机视觉、机器人、约束满足问题、软硬件及应用七大类;不同类型文献的前沿主题在不同时间段内,既展现持续性,又呈现出动态变化的特性,而在同一时间段内则各有侧重;在人工智能领域,不同数据源的前沿主题展现出显著的演化差异,论文前沿主题在各个阶段的演化能力差异较大,发展方向日趋多元;基金的前沿主题显示出强烈的演化性,发展方向多样;专利前沿主题演化差异较小,发展方向相对固定;在演化过程中,各阶段关注的热点与新兴前沿主题存在显著差异。 展开更多
关键词 多源数据 前沿主题识别 BERT-LDA 动态演化分析 多维指标
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