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ADGAP:a user-friendly online ancient DNA database and genome analysis platform
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作者 Yanwei Chen Yu Xu +1 位作者 Kongyang Zhu Chuan-Chao Wang 《Journal of Genetics and Genomics》 2025年第8期1058-1061,共4页
The analysis of ancient genomics provides opportunities to explore human population history across both temporal and geographic dimensions(Haak et al.,2015;Wang et al.,2021,2024)to enhance the accessibility and utilit... The analysis of ancient genomics provides opportunities to explore human population history across both temporal and geographic dimensions(Haak et al.,2015;Wang et al.,2021,2024)to enhance the accessibility and utility of these ancient genomic datasets,a range of databases and advanced statistical models have been developed,including the Allen Ancient DNA Resource(AADR)(Mallick et al.,2024)and AdmixTools(Patterson et al.,2012).While upstream processes such as sequencing and raw data processing have been streamlined by resources like the AADR,the downstream analysis of these datasets-encompassing population genetics inference and spatiotemporal interpretation-remains a significant challenge.The AADR provides a unified collection of published ancient DNA(aDNA)data,yet its file-based format and reliance on command-line tools,such as those in Admix-Tools(Patterson et al.,2012),require advanced computational expertise for effective exploration and analysis.These requirements can present significant challenges forresearchers lackingadvanced computational expertise,limiting the accessibility and broader application of these valuable genomic resources. 展开更多
关键词 database raw data processing analysis ancient genomics upstream processes ancient DNA explore human population history allen ancient dna resource aadr mallick ancient genomic datasetsa
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Semantic-based query processing for relational data integration 被引量:1
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作者 苗壮 张亚非 +2 位作者 王进鹏 陆建江 周波 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期22-25,共4页
To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,al... To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,all relative tables are found and decomposed into minimal connectable units.Minimal connectable units are joined according to semantic queries to produce the semantically correct query plans.Algorithms for query rewriting and transforming are presented.Computational complexity of the algorithms is discussed.Under the worst case,the query decomposing algorithm can be finished in O(n2) time and the query rewriting algorithm requires O(nm) time.And the performance of the algorithms is verified by experiments,and experimental results show that when the length of query is less than 8,the query processing algorithms can provide satisfactory performance. 展开更多
关键词 data integration relational database simple protocol and RDF query language(SPARQL) minimal connectable unit query processing
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XML-based Data Processing in Network Supported Collaborative Design 被引量:2
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作者 Qi Wang Zhong-Wei Ren Zhong-Feng Guo 《International Journal of Automation and computing》 EI 2010年第3期330-335,共6页
In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative ... In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language (XML) based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data (STEP) with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language (SQL) queries. Finally, the structure of data processing system based on XML is presented. 展开更多
关键词 Extensible markup language (XML) network supported collaborative design standard for the exchange of product model data (STEP) data analysis data processing relational database
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A MAPPING APPROACH TO RESOLVING SCHEMA INCOMPATIBILITY IN A FEDERATED DATABASE SYSTEM
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作者 金远平 《Journal of Southeast University(English Edition)》 EI CAS 1992年第2期30-35,共6页
Schema incompatibility is a major challenge to a federated database systemfor data sharing among heterogeneous,multiple and autonomous databases.This paperpresents a mapping approach based on import schema,export sche... Schema incompatibility is a major challenge to a federated database systemfor data sharing among heterogeneous,multiple and autonomous databases.This paperpresents a mapping approach based on import schema,export schema and domain conver-sion function,through which schema incompatibility problems such as naming conflict,domain incompatibility and entity definition incompatibility can be resolved effectively.The implementation techniques are also discussed. 展开更多
关键词 data management data retrievAL federated database database integration
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Database of molecular masers and variable stars
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作者 Andrej M.Sobolev Dmitry A. Ladeyschikov Jun-ichi Nakashima 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期13-20,共8页
We present the database of maser sources in H2 O, OH and Si O lines that can be used to identify and study variable stars at evolved stages. Detecting the maser emission in H2 O, OH and Si O molecules toward infrared-... We present the database of maser sources in H2 O, OH and Si O lines that can be used to identify and study variable stars at evolved stages. Detecting the maser emission in H2 O, OH and Si O molecules toward infrared-excess objects is one of the methods for identifing long-period variables(LPVs, including miras and semiregulars), because these stars exhibit maser activity in their circumstellar shells. Our sample contains 1803 known LPV objects. Forty-six percent of these stars(832 objects) manifest maser emission in the line of at least one molecule: H2 O, OH or Si O. We use the database of circumstellar masers in order to search for LPVs which are not included in the General Catalogue of Variable Stars(GCVS). Our database contains 4806 objects(3866 objects without associations in GCVS) with maser detection in at least one molecule. Therefore it is possible to use the database in order to locate and study the large sample of LPV stars. The database can be accessed at http://maserdb.net. 展开更多
关键词 catalogs-astronomical databaseS STARS VARIABLES general-stars masers-physical data and processes
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A Shallow Parsing Approach to Natural Language Queries of a Database
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作者 Richard Skeggs Stasha Lauria 《Journal of Software Engineering and Applications》 2019年第9期365-382,共18页
The performance and reliability of converting natural language into structured query language can be problematic in handling nuances that are prevalent in natural language. Relational databases are not designed to und... The performance and reliability of converting natural language into structured query language can be problematic in handling nuances that are prevalent in natural language. Relational databases are not designed to understand language nuance, therefore the question why we must handle nuance has to be asked. This paper is looking at an alternative solution for the conversion of a Natural Language Query into a Structured Query Language (SQL) capable of being used to search a relational database. The process uses the natural language concept, Part of Speech to identify words that can be used to identify database tables and table columns. The use of Open NLP based grammar files, as well as additional configuration files, assist in the translation from natural language to query language. Having identified which tables and which columns contain the pertinent data the next step is to create the SQL statement. 展开更多
关键词 NLIDB NATURAL LANGUAGE processing database QUERY data MINING
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The Organizing of Database from Surlari National Geomagnetic Observatory
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作者 Natalia-Silvia Asimopolos Laurentiu Asimopolos +1 位作者 Bogdan Balea Adrian Aristide Asimopolos 《Journal of Environmental Science and Engineering(A)》 2021年第1期26-33,共8页
Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform... Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform the processing and analysis of geomagnetic parameters through different spectral,statistical and correlation methods.All these parameters are included in the geomagnetic database on server.The web interface for the database meets the different needs of handling the data collected,raw or processed.The server-side programming language used for design is php.This allow us to select different periods for which access to stored data,required for different search filters and different parameters or data from different time periods can be compared.For a more in-depth analysis of the stored data,through JavaScript programming language graphs for different parameters can be drawn.Access to the web interface can be done with or without authentication,depending on the need to ensure the security of certain data collected,stored and processed.The applications are scalable for different devices that will access it:mobile,tablets,laptops or desktops. 展开更多
关键词 Geomagnetic observatory database data in real time data acquisition data processing
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基于iData数据工厂的地形图入库方案及关键技术研究 被引量:7
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作者 佘娣 《城市勘测》 2020年第1期57-60,共4页
地形图数据入库是智慧城市基础地理信息建设中非常重要的内容。文章先是对目前行业内相关技术发展现状进行了阐述,分析了地形图入库的难点,然后介绍了iData数据工厂的地形图入库流程,同时根据相关项目设计了相应的数据库模板和入库转换... 地形图数据入库是智慧城市基础地理信息建设中非常重要的内容。文章先是对目前行业内相关技术发展现状进行了阐述,分析了地形图入库的难点,然后介绍了iData数据工厂的地形图入库流程,同时根据相关项目设计了相应的数据库模板和入库转换方案,并将其投入应用。结果表明,基于iData数据工厂的地形图入库方案不仅操作简便,易于掌握,且灵活度高,适用范围广,是一种高效的数据处理方法。 展开更多
关键词 idata数据工厂 地形图 数据库 数据处理
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Open Data Services和Socket的应用研究——数据库服务器与应用程序间网络通信接口模块的设计 被引量:2
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作者 张玮 《江西气象科技》 2004年第1期33-36,共4页
在数据库应用系统开发时常遇到的问题是如何合理的设计外部进程访问数据库的时间控制方案,在满足设计要求的响应时间的前提下,把握好系统与网络负载同系统事务响应处理速度之间的平衡关系。但在实际开发过程中对于某些类型数据的响应处... 在数据库应用系统开发时常遇到的问题是如何合理的设计外部进程访问数据库的时间控制方案,在满足设计要求的响应时间的前提下,把握好系统与网络负载同系统事务响应处理速度之间的平衡关系。但在实际开发过程中对于某些类型数据的响应处理缺乏有效率的解决途径。此类数据采用通常的处理方式往往不能较好地得到解决。基于此,开发了1种由ODSAPI和Socket编程的数据库ESP扩展方法,由应用系统主动查询方式变为数据库系统主动通知或推送的方式,从而提供了1种高效率的解决方案。 展开更多
关键词 开放数据服务 数据库 触发器 存储过程
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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Research of intelligence data mining based on commanding decision-making 被引量:1
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作者 Liu Jingxue Fei Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期275-280,共6页
In order to rapidly and effectively meet the informative demand from commanding decision-making, it is important to build, maintain and mine the intelligence database. The type, structure and maintenance of military i... In order to rapidly and effectively meet the informative demand from commanding decision-making, it is important to build, maintain and mine the intelligence database. The type, structure and maintenance of military intelligence database are discussed. On this condition, a new data-mining arithmetic based on relation intelligence database is presented according to the preference information and the requirement of time limit given by the commander. Furthermore, a simple calculative example is presented to prove the arithmetic with better maneuverability. Lastly, the problem of how to process the intelligence data mined from the intelligence database is discussed. 展开更多
关键词 Intelligence requirement Intelligence database database maintenance data mining arithmetic Intelligence processing.
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Stream Segmentation-A Data Fusion Approach for Sensor Networks 被引量:1
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作者 WU Jian-Kang DONG Liang BAO Xiao-Ming 《自动化学报》 EI CSCD 北大核心 2006年第6期856-866,共11页
Sensor networks provide means to link people with real world by processing data in real time collected from real-world and routing the query results to the right people. Application examples include continuous monitor... Sensor networks provide means to link people with real world by processing data in real time collected from real-world and routing the query results to the right people. Application examples include continuous monitoring of environment, building infrastructures and human health. Many researchers view the sensor networks as databases, and the monitoring tasks are performed as subscriptions, queries, and alert. However, this point is not precise. First, databases can only deal with well-formed data types, with well-defined schema for their interpretation, while the raw data collected by the sensor networks, in most cases, do not fit to this requirement. Second, sensor networks have to deal with very dynamic targets, environment and resources, while databases are more static. In order to fill this gap between sensor networks and databases, we propose a novel approach, referred to as 'spatiotemporal data stream segmentation', or 'stream segmentation' for short, to address the dynamic nature and deal with 'raw' data of sensor networks. Stream segmentation is defined using Bayesian Networks in the context of sensor networks, and two application examples are given to demonstrate the usefulness of the approach. 展开更多
关键词 Sensor networks spatiotemporal data processing databaseS Bayesian networks
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Optimizing Query Results Integration Process Using an Extended Fuzzy C-Means Algorithm
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作者 Naoual Mouhni Abderrafiaa Elkalay Mohamed Chakraoui 《Journal of Software Engineering and Applications》 2014年第5期354-359,共6页
Cleaning duplicate data is a major problem that persists even though many works have been done to solve it, due to the exponential growth of data amount treated and the necessity to use scalable and speed algorithms. ... Cleaning duplicate data is a major problem that persists even though many works have been done to solve it, due to the exponential growth of data amount treated and the necessity to use scalable and speed algorithms. This problem depends on the type and quality of data, and differs according to the volume of data set manipulated. In this paper we are going to introduce a novel framework based on extended fuzzy C-means algorithm by using topic ontology. This work aims to improve the OLAP querying process over heterogeneous data warehouses that contain big data sets, by improving query results integration, eliminating redundancies by using the extended classification algorithm, and measuring the loss of information. 展开更多
关键词 Clustering Classification and Association RULES database Integration data WAREHOUSE and REPOSITORY Heterogeneous databaseS QUERY processing
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基于微服务架构的电力调度数据综合管理平台
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作者 周志烽 朱文 李映辰 《电气自动化》 2025年第5期4-7,共4页
为了进一步优化数据处理效率和管理能力,提出了一种基于微服务架构的电力能源调度数据综合管理平台。通过采用微服务架构,提升了系统的性能、可扩展性和容错能力,并针对传统单体架构在大规模数据处理中的局限性提出了改进方案;平台引入... 为了进一步优化数据处理效率和管理能力,提出了一种基于微服务架构的电力能源调度数据综合管理平台。通过采用微服务架构,提升了系统的性能、可扩展性和容错能力,并针对传统单体架构在大规模数据处理中的局限性提出了改进方案;平台引入了TDengine数据库,以优化数据存储与查询效率,解决了传统数据库在处理电力能源调度大规模数据时的瓶颈问题;从CPU使用率、内存消耗、响应时间和系统吞吐量等多个维度对平台性能进行了详细评估。结果表明,提出的平台在处理电力能源调度数据时,具有更高的响应速度和数据处理能力,能够为电力行业的调度与能量管理提供高效的解决方案,并为未来大规模电力系统的扩展奠定了基础。 展开更多
关键词 电力能源调度 微服务架构 数据处理优化 能量管理平台 时序数据库 系统扩展性
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Database Research: Achievements and Challenges 被引量:4
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作者 王珊 杜小勇 +1 位作者 孟小峰 陈红 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第5期823-837,共15页
Database system is the infrastructure of the modern information system. The R&D in the database system and its technologies is one of the important research topics in the field. The database R&D in China took off la... Database system is the infrastructure of the modern information system. The R&D in the database system and its technologies is one of the important research topics in the field. The database R&D in China took off later but it moves along by giant steps. This report presents the achievements Renmin University of China (RUC) has made in the past 25 years and at the same time addresses some of the research projects we, RUC, are currently working on. The National Natural Science Foundation of China supports and initiates most of our research projects and these successfully conducted projects have produced fruitful results. 展开更多
关键词 database management system parallel database systems Chinese database systems self-managing databases P2P computing and databases data warehousing OLAP Web data management XML mobile data management semantic web contextual information retrieval
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基于知识图谱的城轨大模型RAG检索增强知识库构建研究 被引量:5
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作者 于松伟 刘巍 +3 位作者 夏秀江 邵昕 韩德志 韩晓艺 《都市快轨交通》 北大核心 2025年第2期1-7,共7页
当前,数据是城轨大模型落地的关键和核心养料,检索增强生成(retrieval-augmented generation,RAG)技术是城轨行业大模型建设和解决大模型幻觉问题的重要手段之一,但却因行业知识库的缺失难以充分发挥效用。本研究通过实体分类表、术语... 当前,数据是城轨大模型落地的关键和核心养料,检索增强生成(retrieval-augmented generation,RAG)技术是城轨行业大模型建设和解决大模型幻觉问题的重要手段之一,但却因行业知识库的缺失难以充分发挥效用。本研究通过实体分类表、术语词典、属性库、实体关系表,创建分类骨架-语义基准-特征规则-逻辑关系四维架构,尤其新增实体的行业属性,突破传统知识图谱的实体A-关系-实体B三元组架构,从而形成标准化与立体化的行业知识体系。基于此构建的高质量行业知识库作为RAG技术的核心组件,通过数据采集→结构化→向量化→知识化的链路,为大模型提供标准、可信、可溯的领域知识,显著提升城轨大模型生成内容的的可靠性和专业性,为城轨行业迈向数据驱动与知识驱动的新阶段提供核心支撑。 展开更多
关键词 城市轨道交通 人工智能 大模型 DeepSeek RAG 知识库 知识图谱 向量数据库 数据标注
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国际联机检索数据库Dialog的历史回顾与当下启示
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作者 董昊南 陈定权 李帅 《图书馆论坛》 北大核心 2025年第11期35-47,共13页
国际联机检索数据库Dialog(Dialog数据库)是一个集资源、服务、技术于一体的集合体,其诞生对计算机情报检索有着划时代意义。Dialog数据库不仅是全球联机数据库的先驱者,还对我国信息资源开发的研究和实践有着重大影响。文章通过历史研... 国际联机检索数据库Dialog(Dialog数据库)是一个集资源、服务、技术于一体的集合体,其诞生对计算机情报检索有着划时代意义。Dialog数据库不仅是全球联机数据库的先驱者,还对我国信息资源开发的研究和实践有着重大影响。文章通过历史研究法、案例研究法和文献分析法,基于历史文献资料,系统回顾Dialog数据库60余年的发展历史,将其划分为孕育、成长、衰退和复苏四个阶段,分析Dialog数据库对情报检索技术、联机信息服务、信息产业和图书情报工作的历史贡献。并以Dialog数据库信息资源开发的历史经验和教训为镜鉴,从资源、服务、技术视角为我国当下数据资源开发提出三点启示:坚持开放互联,深度开发数据资源;坚持场景驱动,打造数据资源服务模式;坚持“技术为用”,积极采纳新技术。 展开更多
关键词 联机情报检索系统 数据库 DIALOG 数据资源开发 图书情报技术史
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基于分类识别的工程档案数据快速检索技术 被引量:2
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作者 王建忠 吴昕达 《电子设计工程》 2025年第2期33-37,共5页
传统的档案数据库检索方法数据处理时间长、效率低,而且使用关系型数据库等传统存储方式的成本高、鲁棒性差,文中以分布式存储数据库HBase为依托,提出了一种基于分类识别的工程档案数据快速检索模型。该模型主要由数据分类识别技术和数... 传统的档案数据库检索方法数据处理时间长、效率低,而且使用关系型数据库等传统存储方式的成本高、鲁棒性差,文中以分布式存储数据库HBase为依托,提出了一种基于分类识别的工程档案数据快速检索模型。该模型主要由数据分类识别技术和数据快速检索技术模块组成。数据分类识别技术针对传统TF-IDF算法存在单词位置信息不敏感的缺点,使用类间和类内方法进行改进,并与朴素贝叶斯网络结合来提升分类识别准确率。数据快速检索技术模块则利用CNN和LSTM进行数据特征提取,采用哈希算法生成数据哈希码,提升了检索速度。在实验测试中,改进TF-IDF算法在不同数据集中准确率、召回率和F1值指标均为最优,检索时间缩短了10%以上且鲁棒性较强。实验结果表明所提方法超越了传统手段,兼具高效性与稳定性。 展开更多
关键词 分布式数据库 TF-IDF 深度哈希算法 朴素贝叶斯 数据检索
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Android APP取证:应对工具提取难题的一种方法
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作者 姜贤波 邢桂东 +5 位作者 刘宁 曹军 陈业盛 林承裕 鄢飞 康艳荣 《刑事技术》 2025年第4期426-430,共5页
随着技术的进步,面对不断更新的操作系统和强化的数据加密技术,移动设备取证变得越来越困难。本文围绕一起实际案例中华为手机抖音应用的数据提取需求,探讨了新型Android手机中特定应用数据提取的问题,研究提出了利用具有root权限的手... 随着技术的进步,面对不断更新的操作系统和强化的数据加密技术,移动设备取证变得越来越困难。本文围绕一起实际案例中华为手机抖音应用的数据提取需求,探讨了新型Android手机中特定应用数据提取的问题,研究提出了利用具有root权限的手机对源设备进行数据克隆后提取数据的方法,成功提取到所需的数据信息。同时,针对手工分析数据库特定时间段的应用使用情况时,传统的手动时间戳转换方法效率低下、耗时长等问题,本研究开发了一款新型软件工具,能够自动检索指定目录下多个数据库中关键时间段的数据,并进行快速分析,大幅提升了处理速度,提高了效率。本研究提供了一种应对数据提取及分析难题的方法,能为相关案件的移动设备取证提供方法参考。 展开更多
关键词 手机取证 数据挖掘 电子物证 手机应用分析 数据库检索工具
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智能云平台异构数据库匹配检索算法研究 被引量:1
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作者 吴华锋 《无线互联科技》 2025年第9期17-22,共6页
文章提出了一种基于智能云平台的异构数据库匹配检索算法,旨在解决多模态数据源的高效整合与匹配问题。通过构建数据模型转换框架和基于深度学习的匹配模型,所提算法显著提高了检索精度和响应速度。实验结果验证了该算法在医疗健康和金... 文章提出了一种基于智能云平台的异构数据库匹配检索算法,旨在解决多模态数据源的高效整合与匹配问题。通过构建数据模型转换框架和基于深度学习的匹配模型,所提算法显著提高了检索精度和响应速度。实验结果验证了该算法在医疗健康和金融风控等领域的有效性,其满足了实时性和准确性的要求。研究为智能云平台中的异构数据处理提供了理论依据和技术支持,对大规模数据整合与检索任务的优化具有重要意义。 展开更多
关键词 智能云平台 异构数据库 匹配检索 深度学习 数据模型转换 算法优化
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