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Comprehensive security risk factor identification for small reservoirs with heterogeneous data based on grey relational analysis model 被引量:6
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作者 Jing-chun Feng Hua-ai Huang +1 位作者 Yao Yin Ke Zhang 《Water Science and Engineering》 EI CAS CSCD 2019年第4期330-338,共9页
Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when ... Identification of security risk factors for small reservoirs is the basis for implementation of early warning systems.The manner of identification of the factors for small reservoirs is of practical significance when data are incomplete.The existing grey relational models have some disadvantages in measuring the correlation between categorical data sequences.To this end,this paper introduces a new grey relational model to analyze heterogeneous data.In this study,a set of security risk factors for small reservoirs was first constructed based on theoretical analysis,and heterogeneous data of these factors were recorded as sequences.The sequences were regarded as random variables,and the information entropy and conditional entropy between sequences were measured to analyze the relational degree between risk factors.Then,a new grey relational analysis model for heterogeneous data was constructed,and a comprehensive security risk factor identification method was developed.A case study of small reservoirs in Guangxi Zhuang Autonomous Region in China shows that the model constructed in this study is applicable to security risk factor identification for small reservoirs with heterogeneous and sparse data. 展开更多
关键词 Security risk factor identification Heterogeneous data Grey relational analysis model relational degree Information entropy Conditional entropy Small reservoir GUANGXI
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Spatio-temporal Data Model Based on Relational Database System
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作者 SHA Zongyao BIAN Fuling 《Geo-Spatial Information Science》 2002年第2期22-27,共6页
In this paper,the entity_relation data model for integrating spatio_temporal data is designed.In the design,spatio_temporal data can be effectively stored and spatiao_temporal analysis can be easily realized.
关键词 GIS spatio_temporal data model relational database spatio_temporal analysis
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Developing a Data Modelling Tool to Visualize the Transformation of an ER Diagram into a Relational Schema
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作者 Elitsa Silyanova Arsova Silyan Sibinov Arsov 《Computer Technology and Application》 2012年第3期201-205,共5页
In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' foc... In this paper, the authors present the development of a data modelling tool that visualizes the transformation process of an "Entity-Relationship" Diagram (ERD) into a relational database schema. The authors' focus is the design of a tool for educational purposes and its implementation on e-learning database course. The tool presents two stages of database design. The first stage is to draw ERD graphically and validate it. The drawing is done by a learner. Then at second stage, the system enables automatically transformation of ERD to relational database schema by using common rules. Thus, the learner could understand more easily how to apply the theoretical material. A detailed description of system functionalities and algorithm for the conversion are proposed. Finally, a user interface and usage aspects are exposed. 展开更多
关键词 E-learning course data modelling tool entity-relationship model relational model.
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Enhancing Relational Triple Extraction in Specific Domains:Semantic Enhancement and Synergy of Large Language Models and Small Pre-Trained Language Models 被引量:1
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作者 Jiakai Li Jianpeng Hu Geng Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2481-2503,共23页
In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured information.Existing relational triple e... In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured information.Existing relational triple extraction models facemultiple challenges when processing domain-specific data,including insufficient utilization of semantic interaction information between entities and relations,difficulties in handling challenging samples,and the scarcity of domain-specific datasets.To address these issues,our study introduces three innovative components:Relation semantic enhancement,data augmentation,and a voting strategy,all designed to significantly improve the model’s performance in tackling domain-specific relational triple extraction tasks.We first propose an innovative attention interaction module.This method significantly enhances the semantic interaction capabilities between entities and relations by integrating semantic information fromrelation labels.Second,we propose a voting strategy that effectively combines the strengths of large languagemodels(LLMs)and fine-tuned small pre-trained language models(SLMs)to reevaluate challenging samples,thereby improving the model’s adaptability in specific domains.Additionally,we explore the use of LLMs for data augmentation,aiming to generate domain-specific datasets to alleviate the scarcity of domain data.Experiments conducted on three domain-specific datasets demonstrate that our model outperforms existing comparative models in several aspects,with F1 scores exceeding the State of the Art models by 2%,1.6%,and 0.6%,respectively,validating the effectiveness and generalizability of our approach. 展开更多
关键词 relational triple extraction semantic interaction large language models data augmentation specific domains
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PORLES:A Parallel Object Relational Database System
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作者 Sun Yong\|qiang, Xu Shu\|ting, Zhu Feng\|hua, Lai Shu\|huaDepartment of Computer Science and Engineering, Shanghai Jiaotong University, Shanghai 200030,China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期100-109,共10页
We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel que... We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel query optimization, transaction processing system and parallel access method in detail. 展开更多
关键词 parallel object relational database BSP model data model query optimization
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Research of storage technique for C-Temporal Relation Data Model
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作者 WANG Zhi-wen CAI Qi-xian Wang Hu-Qi 《微计算机信息》 北大核心 2008年第9期273-275,共3页
As there is datum redundancy in tradition database and temporal database in existence and the quantities of temporal database are increasing fleetly.We put forward compress storage tactics for temporal datum which com... As there is datum redundancy in tradition database and temporal database in existence and the quantities of temporal database are increasing fleetly.We put forward compress storage tactics for temporal datum which combine compress technology in existence in order to settle datum redundancy in the course of temporal datum storage and temporal datum of slow acting domain and momentary acting domain are accessed by using each from independence clock method and mutual clock method.We also bring forward strategy of gridding storage to resolve the problems of temporal datum rising rapidly. 展开更多
关键词 Temporal relation data model Datum redundancy Compress storage Independence clock method Mutual clock method Gridding Storage
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Application of a mixed DEA model to evaluate relative efficiency validity 被引量:2
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作者 FU Yu-wei YIN Hang YANG Gui-bin 《Journal of Marine Science and Application》 2005年第3期64-70,共7页
Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at p... Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at present, the C2R model and the C2GS2 model have limitations when used alone,resulting in evaluations that are often unsatisfactory. In order to solve this problem, a mixed DEA model is built and is used to evaluate the validity of the business efficiency of listed companies. An explanation of how to use this mixed DEA model is offered and its feasibility is verified. 展开更多
关键词 decision making units (DMU) efficiency evaluating mixed data envelopment analysis (DEA) model relative efficiency
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GIS Conceptual Data Model
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作者 XIAO Lebin ZHONG Ershun LIU Jiyuan SONG Guanfuassociate researcher,Institute of Geographic Sciences and Natural Resources,Chinese Academy of Sciences,3 Datun Road,Anwai,Beijing 100101,China. 《Geo-Spatial Information Science》 2002年第3期19-25,共7页
In order to set up a conceptual data model that reflects the real world as accurately as possible,this paper firstly reviews and analyzes the disadvantages of previous conceptual data models used by traditional GIS in... In order to set up a conceptual data model that reflects the real world as accurately as possible,this paper firstly reviews and analyzes the disadvantages of previous conceptual data models used by traditional GIS in simulating geographic space,gives a new explanation to geographic space and analyzes its various essential characteristics.Finally,this paper proposes several detailed key points for designing a new type of GIS data model and gives a simple holistic GIS data model. 展开更多
关键词 TOPOLOGICAL relatION LAYER GEOGRAPHIC SPACE HOLISTIC data model
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Application of the Conceptualization Groundwater Data Model to Study the Upper Arkansas River Corridor,Western Kansas
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作者 Xiaoying Yang 《Journal of Earth Science》 SCIE CAS CSCD 2012年第1期77-87,共11页
Large-scale water pumping has caused significant decline in groundwater level in the Upper Arkansas corridor region, which in turn has triggered a chain of hydrological and ecological impacts. A newly developed concep... Large-scale water pumping has caused significant decline in groundwater level in the Upper Arkansas corridor region, which in turn has triggered a chain of hydrological and ecological impacts. A newly developed conceptualization groundwater data model was used to organize various datasets on the Upper Arkansas corridor groundwater system and to develop a MODFLOW model to simulate groundwater flow in the region from 1959 to 2005. The simulation results have shown a sig- nificant decline in groundwater level and the conversion of Arkansas River from a gaining river to a losing river in the western two-thirds of the study area. Correlation analysis between percentage of salt cedar and the hydrogeological conditions indicates that these hydrogeological changes at least partially account for invasion of salt cedar that is more drought tolerant. The analysis also illustrates the com- plexity of the interaction mechanisms between hydrological conditions and salt cedar distribution, and suggests the need for better data on salt cedar distribution with higher spatial resolution and across larger hydrological gradients. 展开更多
关键词 groundwater/surface-water relation invasive species High Plains data model geo- graphic information system.
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On the Relation Redundancy in Fuzzy Databases
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作者 唐晓辉 陈国青 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期67-70,83,共5页
This paper concentrates on the problem of data redundancy under the extended-possibility-based model. Based on the information gain in data classification, a measure - relation redundancy - is proposed to evaluate the... This paper concentrates on the problem of data redundancy under the extended-possibility-based model. Based on the information gain in data classification, a measure - relation redundancy - is proposed to evaluate the degree of a given relation being redundant in whole. The properties of relation redundancy are also investigated. This new measure is useful in dealing with data redundancy. 展开更多
关键词 fuzzy relational data model CLOSENESS relation redundancy.
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Data Models Comparison and Experimental Design of Database Course
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作者 Fengli Zhang Xin Lu Reijin Wang 《计算机教育》 2021年第12期179-188,共10页
Data model is the core knowledge of database course.A deep understanding of data model is the key to mastering database design and application.The data models of NoSQL databases are categorized as key-value stores,col... Data model is the core knowledge of database course.A deep understanding of data model is the key to mastering database design and application.The data models of NoSQL databases are categorized as key-value stores,column-oriented stores,document-oriented stores and graph databases.This paper makes a comparative analysis of the characteristics of the relational data model and NoSQL data models,and gives the design and implementation of different data models combined with cases,so that students can master the relevant theories and application methods of the database model. 展开更多
关键词 data model relational NOSQL course practice
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On Detecting and Enforcing the Non-Relational Constraints Associated to Dyadic Relations in MatBase
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作者 Christian Mancas 《Journal of Electronic & Information Systems》 2020年第2期1-8,共8页
MatBase is a prototype data and knowledge base management expert intelligent system based on the Relational,Entity-Relationship,and(Elementary)Mathematical Data Models.Dyadic relationships are quite common in data mod... MatBase is a prototype data and knowledge base management expert intelligent system based on the Relational,Entity-Relationship,and(Elementary)Mathematical Data Models.Dyadic relationships are quite common in data modeling.Besides their relational-type constraints,they often exhibit mathematical properties that are not covered by the Relational Data Model.This paper presents and discusses the MatBase algorithm that assists database designers in discovering all non-relational constraints associated to them,as well as its algorithm for enforcing them,thus providing a significantly higher degree of data quality. 展开更多
关键词 Conceptual data modeling database constraints theory Non-relational constraints data structures and algorithms for data management Dyadic relation properties data quality (Elementary)Mathematical data model MatBase
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Intelligent ETL for Enterprise Software Applications Using Unstructured Data
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作者 Manthan Joshi Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2025年第1期44-65,共22页
Enterprise applications utilize relational databases and structured business processes, requiring slow and expensive conversion of inputs and outputs, from business documents such as invoices, purchase orders, and rec... Enterprise applications utilize relational databases and structured business processes, requiring slow and expensive conversion of inputs and outputs, from business documents such as invoices, purchase orders, and receipts, into known templates and schemas before processing. We propose a new LLM Agent-based intelligent data extraction, transformation, and load (IntelligentETL) pipeline that not only ingests PDFs and detects inputs within it but also addresses the extraction of structured and unstructured data by developing tools that most efficiently and securely deal with respective data types. We study the efficiency of our proposed pipeline and compare it with enterprise solutions that also utilize LLMs. We establish the supremacy in timely and accurate data extraction and transformation capabilities of our approach for analyzing the data from varied sources based on nested and/or interlinked input constraints. 展开更多
关键词 Structured data relational model LLM-Powered Agents Field-Level Extraction Knowledge Graph
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基于多模态数据的粮食应急体系构成要素提取及其作用关系
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作者 王琳 马思维 《中国农业大学学报》 北大核心 2026年第1期212-225,共14页
为厘清粮食应急体系的构成要素及要素间的作用关系,采用扎根理论,对搜集整理的170份粮食应急体系相关案例、文献、政策文件、访谈以及视频数据进行要素提取,并结合物理-事理-人理(WSR)方法论和刺激-机体-反应(SOR)理论构建粮食应急体系... 为厘清粮食应急体系的构成要素及要素间的作用关系,采用扎根理论,对搜集整理的170份粮食应急体系相关案例、文献、政策文件、访谈以及视频数据进行要素提取,并结合物理-事理-人理(WSR)方法论和刺激-机体-反应(SOR)理论构建粮食应急体系构成要素的作用关系模型。结果表明:1)粮食应急体系的构成要素包括市场环境、突发事件、流通渠道、应急预案、基础设施、信息共享和组织协调7个要素;2)市场环境和突发事件属于物理维度要素,对体系起刺激作用;流通渠道、应急预案和基础设施属于事理维度要素,承担体系的机体功能;信息共享和组织协调属于人理维度要素,对体系起反应作用。根据粮食应急体系作用关系模型得出结论与政策建议,为完善粮食应急体系提供了理论支持和实践依据。 展开更多
关键词 粮食应急体系 多模态数据 构成要素 扎根理论 作用关系模型
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基于大语言模型的弱结构化数据通用问答对实体关系抽取研究
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作者 张天舒 申姝婧 +1 位作者 张子成 杨建林 《情报理论与实践》 北大核心 2026年第2期179-188,共10页
[目的/意义]弱结构化数据因其隐含语义特征而具有较高的潜在价值,但其非规范性和异构性的表征形式使得传统方法在处理该类数据时面临抽取效果不佳和标注成本高等问题。本文提出一种基于大语言模型的实体关系抽取通用框架,通过大语言模... [目的/意义]弱结构化数据因其隐含语义特征而具有较高的潜在价值,但其非规范性和异构性的表征形式使得传统方法在处理该类数据时面临抽取效果不佳和标注成本高等问题。本文提出一种基于大语言模型的实体关系抽取通用框架,通过大语言模型强大的泛化、生成和推理能力,在标注资源有限和需求快速迭代的场景下为弱结构化数据处理提供高效、可扩展的解决方案。[方法/过程]该框架结合提示工程将抽取任务划分为问答对重构、实体识别、关系抽取与三元组增强4个阶段,有效提升了抽取任务的准确性与鲁棒性。本文以江苏省13个地级市的政府信箱问答数据为应用案例验证该框架的有效性。[结果/结论]实验表明,该框架在精确率、召回率和F1值等方面均表现优异,尤其Qwen模型在多个主流中文大语言模型中效果最佳。进一步实证发现,所提出方法能够准确识别“诉求事项—回应内容”等核心实体,不仅验证了该方法在问答数据中的应用价值,而且对政务信息智能化管理实践具有重要参考价值。 展开更多
关键词 大语言模型 实体识别 关系抽取 弱结构化数据 知识抽取
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基于面向对象技术和标准关系数据库的Geodatabase的研究 被引量:3
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作者 刘艳丰 姜耀鹏 《测绘与空间地理信息》 2009年第4期139-142,共4页
面向对象技术为空间数据模型的发展提出了新的要求。本论文在此背景下,回顾了空间数据模型的发展历程,从整体上介绍了第三代基于面向对象技术和关系数据库的Geodatabase数据模型,并详细介绍了其体系结构及在关系数据库中的存储。最后本... 面向对象技术为空间数据模型的发展提出了新的要求。本论文在此背景下,回顾了空间数据模型的发展历程,从整体上介绍了第三代基于面向对象技术和关系数据库的Geodatabase数据模型,并详细介绍了其体系结构及在关系数据库中的存储。最后本文通过总结Geodatabase模型的优缺点,提出了未来空间数据模型的发展趋势。 展开更多
关键词 面向对象 空间数据模型 GEOdataBASE 关系数据库
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结合数据增强与实体映射CasRel模型的名家医案联合关系抽取
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作者 李钰欣 向兴华 +7 位作者 杨航 刘大胜 王嘉恒 赵志伟 韩嘉旭 吴孟洁 车前子 杨伟 《中国实验方剂学杂志》 北大核心 2026年第2期218-225,共8页
目的:针对中医名家医案的非结构化文言表述、实体关系嵌套及标注数据稀缺问题,构建结合数据增强与实体映射的联合关系抽取框架,为中医诊疗知识图谱构建及临床规律挖掘提供技术支撑。方法:构建名家医案文本实体及其关系的标注结构,采用... 目的:针对中医名家医案的非结构化文言表述、实体关系嵌套及标注数据稀缺问题,构建结合数据增强与实体映射的联合关系抽取框架,为中医诊疗知识图谱构建及临床规律挖掘提供技术支撑。方法:构建名家医案文本实体及其关系的标注结构,采用数据增强策略,整合多部古籍扩充医案关系抽取数据集,设计适配中医语义的基于级联二值标记的关系联合抽取(CasRel)模型,引入中医经典文本预训练双向编码器表征法(BERT)编码层,增强对古汉语的语义表征,采用头实体-关系-尾实体映射机制,同步解决实体嵌套与关系重叠问题。结果:相较于基于流水线的Bert-Radical-Lexicon(BRL)-双向长短期记忆网络-注意力机制(BiLSTM-Attention)模型,结合数据增强与实体映射的联合关系抽取CasRel模型展现出了更为显著的性能优势,在病症关系、舌证关系、因证关系、方证关系等共12类关系的综合精确率为65.73%、召回率为64.03%、F_(1)值为64.87%,比流水线的BRL-BiLSTM-Attention模型的综合精确率、召回率、F_(1)值分别提升14.26%、7.98%、11.21%。其中舌证关系(F_(1)值为69.32%,提升22.68%)提升显著,方证关系表现最优(F_(1)值为70.10%,提升9.93%)。结论:该研究通过数据增强与联合解码,显著改善中医文本的语义隐含与实体间复杂依赖性问题,为中医医案结构化挖掘提供可复用技术框架,所构建的知识图谱可支撑临床辨证选方与用药配伍优化,也为中医人工智能研究提供方法论参考。 展开更多
关键词 数据增强 名家医案 关系抽取 联合方法 基于级联二值标记的关系联合抽取(CasRel)模型 知识图谱
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基于自然语言处理的职务犯罪法律文书处理与分析研究
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作者 姜志超 杨炳文 +1 位作者 高谷刚 李林怡 《通信与信息技术》 2026年第1期7-12,30,共7页
近年来,职务犯罪案件频发,现有研究多局限于法律文本和犯罪构成分析,缺乏跨学科视角,难以揭示其特征和发展趋势。目前,专门针对职务犯罪文书处理与分析的类似系统较少,法律领域通用的数据分析系统难以处理此类文书的专业性和特殊性。因... 近年来,职务犯罪案件频发,现有研究多局限于法律文本和犯罪构成分析,缺乏跨学科视角,难以揭示其特征和发展趋势。目前,专门针对职务犯罪文书处理与分析的类似系统较少,法律领域通用的数据分析系统难以处理此类文书的专业性和特殊性。因此,借助大数据、人工智能和自然语言处理技术,分析职务犯罪案例文本,揭示犯罪规律并实现高效预防具有重要意义。本研究提出基于智能数据处理与分析的职务犯罪研究模型与算法,并构建了系统原型。通过定制化爬虫技术高效采集多平台职务犯罪文书数据。在数据预处理阶段,采用jieba分词结合深度学习序列标注技术进行清洗、分词及关键信息提取。基于Word2Vec模型将文本信息转化为数字化表达,并结合K-Means聚类算法与Llama3大语言模型挖掘关键特征,显著提升类案检索精准性。最终通过箱线图、散点图等可视化手段展示犯罪规律。实验结果表明,相较于传统方法,该模型在精确度和召回率方面分别提升了21%和9%,充分验证了Llama3在语义理解和特征提取方面的强大能力。 展开更多
关键词 职务犯罪 法律文书 大数据 自然语言处理 词向量模型 聚类算法
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利用Geodatabase建模
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作者 杨正银 《四川测绘》 2007年第6期248-251,共4页
本文介绍了采用面向对象技术的新一代地理数据模型Geodatabase的特点,举例说明了利用Geodatabase数据模型对地理对象建模的过程及其在数字中国地理空间框架建设中的重要意义。
关键词 特征 特征集 面向对象数据模型 关系-对象数据库
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A STUDY ON THE REGULATORY PATHWAY FOR THE CIRCULATION OF ELDERLY-RELATED DATA UNDER THE EMERGING INTEGRATED MEDICAL AND ELDERLY CARE MODEL
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作者 Tan Ji 《China Legal Science》 2025年第5期57-83,共27页
Within the new model of integrated medical and elderly care services,elderly-related data manifest a composite rights structure that integrates both public and private law dimensions.The granular and multi-dimensional... Within the new model of integrated medical and elderly care services,elderly-related data manifest a composite rights structure that integrates both public and private law dimensions.The granular and multi-dimensional nature and heightened sensitivity of such data,combined with the inherent vulnerability and dependency of elderly-related data subjects,render the regulatory landscape particularly complex.Existing mechanisms for data circulation reveal deficiencies,including fragmented legal norms,indeterminate allocation of data ownership,and supervisory inadequacy.This paper conducts a doctrinal inquiry into the legal relationships among multiple stakeholders across three principal dimensions:data service authorisation,data transmission and operation,and data supervision and safeguard.It proposes a regulatory framework based on a dual-track mechanism-combining top-down harmonisation of existing legal provisions with bottom-up implementation of data trusts-supported by a comprehensive oversight architecture involving government agencies,public interest organisations,and industry associations.This framework is intended to ensure the effective protection of the rights and interests of digitally vulnerable elderly individuals. 展开更多
关键词 integrated medical elderly care model granular multi dimensional nature regulatory landscape elderly related data integrated medical elderly care serviceselderly related composite rights structure regulatory pathway public private law dimensions
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