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Enhancing Data Forwarding Efficiency in SIoT with Multidimensional Social Relations
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作者 Fang Xu Songhao Jiang +3 位作者 Yi Ma Manzoor Ahmed Zenggang Xiong Yuanlin Lyu 《Computers, Materials & Continua》 SCIE EI 2024年第1期1095-1113,共19页
Effective data communication is a crucial aspect of the Social Internet of Things(SIoT)and continues to be a significant research focus.This paper proposes a data forwarding algorithm based on Multidimensional Social ... Effective data communication is a crucial aspect of the Social Internet of Things(SIoT)and continues to be a significant research focus.This paper proposes a data forwarding algorithm based on Multidimensional Social Relations(MSRR)in SIoT to solve this problem.The proposed algorithm separates message forwarding into intra-and cross-community forwarding by analyzing interest traits and social connections among nodes.Three new metrics are defined:the intensity of node social relationships,node activity,and community connectivity.Within the community,messages are sent by determining which node is most similar to the sender by weighing the strength of social connections and node activity.When a node performs cross-community forwarding,the message is forwarded to the most reasonable relay community by measuring the node activity and the connection between communities.The proposed algorithm was compared to three existing routing algorithms in simulation experiments.Results indicate that the proposed algorithmsubstantially improves message delivery efficiency while lessening network overhead and enhancing connectivity and coordination in the SIoT context. 展开更多
关键词 SIoT data forwarding social attributes social relations COMMUNITY
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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
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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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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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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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A Distribution Management System for Relational Databases in Cloud Environments
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作者 Sze-Yao Li Chun-Ming Chang +3 位作者 Yuan-Yu Tsai Seth Chen Jonathan Tsai Wen-Lung Tsai 《Journal of Electronic Science and Technology》 CAS 2013年第2期169-175,共7页
For a transaction processing system to operate effectively and efficiently in cloud environments, it is important to distribute huge amount of data while guaranteeing the ACID (atomic, consistent, isolated, and dura... For a transaction processing system to operate effectively and efficiently in cloud environments, it is important to distribute huge amount of data while guaranteeing the ACID (atomic, consistent, isolated, and durable) properties. Moreover, database partition and migration tools can help transplanting conventional relational database systems to the cloud environment rather than rebuilding a new system. This paper proposes a database distribution management (DBDM) system, which partitions or replicates the data according to the transaction behaviors of the application system. The principle strategy of DBDM is to keep together the data used in a single transaction, and thus, avoiding massive transmission of records in join operations. The proposed system has been implemented successfully. The preliminary experiments show that the DBDM performs the database partition and migration effectively. Also, the DBDM system is modularly designed to adapt to different database management system (DBMS) or different partition algorithms. 展开更多
关键词 data migration database partition distributed database relational database.
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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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An Efficient Schema Transformation Technique for Data Migration from Relational to Column-Oriented Databases
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作者 Norwini Zaidi Iskandar Ishak +1 位作者 Fatimah Sidi Lilly Suriani Affendey 《Computer Systems Science & Engineering》 SCIE EI 2022年第12期1175-1188,共14页
Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However,there is no standard guideline for data transformation from relationa... Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However,there is no standard guideline for data transformation from relational database toNoSQL database. A number of schema transformation techniques have been proposed to improve data transformation process and resulted better query processingtime when compared to the relational database query processing time. However,these approaches produced redundant tables in the resulted schema that in turnconsume large unnecessary storage size and produce high query processing timedue to the generated schema with redundant column families in the transformedcolumn-oriented database. In this paper, an efficient data transformation techniquefrom relational database to column-oriented database is proposed. The proposedschema transformation technique is based on the combination of denormalizationapproach, data access pattern and multiple-nested schema. In order to validate theproposed work, the proposed technique is implemented by transforming data fromMySQL database to MongoDB database. A benchmark transformation techniqueis also performed in which the query processing time and the storage size arecompared. Based on the experimental results, the proposed transformation technique showed significant improvement in terms query processing time and storagespace usage due to the reduced number of column families in the column-orienteddatabase. 展开更多
关键词 data migration data transformation column-oriented database relational database big data
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Spatio-temporal Data Model Based on Relational Database System
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作者 SHAZongyao BIANFuling 《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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Investigation and Design of General Seismic Data Model Based on Relational Database
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作者 Meng En Meng Dong-yue +1 位作者 Wang Hon-gwei Zhao Guang-tao 《石油地球物理勘探》 EI CSCD 北大核心 2009年第A02期151-157,共7页
关键词 关系数据库模型 地震数据 模型设计 对象关系映射 数据存储方式 基础结构 数据共享 石油勘探
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Generalized cone-subconvexlike set-valued maps and applications to vector optimization 被引量:1
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作者 黄永伟 HUANG Yongwei 《Journal of Chongqing University》 CAS 2002年第2期67-71,共5页
The definitions of cone-subconvexlike set-valued maps and generalized cone-subconvexlike set-valued maps in topological vector spaces are defined by using the relative interiors of ordering cone. The relationships bet... The definitions of cone-subconvexlike set-valued maps and generalized cone-subconvexlike set-valued maps in topological vector spaces are defined by using the relative interiors of ordering cone. The relationships between the two classes of set-valued maps are investigated, and some properties of them are shown. A Gordan type alternative theorem under the assumption of generalized cone-subconvexlikeness of set-valued maps is proved by applying convex separation theorems involving the relative interiors in infinite dimensional spaces. Finally a necessary optimality condition theorem is shown for a general kind of set-valued vector optimization in a sense of weak E-minimizer. 展开更多
关键词 relative interiors generalized cone-subconvexlikeness set-valued vector optimization optimality conditions weak E-minimizer.
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Residential Electricity Consumption Behavior Mining Based on System Cluster and Grey Relational Degree
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作者 Mengjia Xu Yuhong Wang 《Energy and Power Engineering》 2017年第4期390-400,共11页
In order to improve the utilization of the residential electricity consumption data which contains the information on the user’s electricity consumption habits, a residential electricity consumption behaviors mining ... In order to improve the utilization of the residential electricity consumption data which contains the information on the user’s electricity consumption habits, a residential electricity consumption behaviors mining algorithm model is constructed. Firstly, according to the attribute, the collected data can be divided into the global data and the phase data, then the appropriate global variables are selected to mine the user’s electricity consumption patterns in the near future on the system clustering algorithm. Based on the theory of grey relational analysis, combing phase data with the power modes to analyze the potential characteristics of residential electricity consumption behaviors deeply that verify the ability of latest power mode to predict household electricity consumption situation in the coming few days and the effect of dominant phase variables on the peak load shifting. Finally, from the actual data of a certain family, the proposed data mining algorithm is testified that it can effectively explore the electricity consumption behavior habits and characteristics of the family. 展开更多
关键词 data Mining ELECTRICITY Consumption Behavior SYSTEM CLUSTER GREY relational Degree
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A Two-Phase Paradigm for Joint Entity-Relation Extraction 被引量:1
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作者 Bin Ji Hao Xu +4 位作者 Jie Yu Shasha Li JunMa Yuke Ji Huijun Liu 《Computers, Materials & Continua》 SCIE EI 2023年第1期1303-1318,共16页
An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during t... An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during the model training,which are essential but result in grossly imbalanced data distributions and in turn cause suboptimal model performance.In order to address the above issues,we propose a two-phase paradigm for the span-based joint entity and relation extraction,which involves classifying the entities and relations in the first phase,and predicting the types of these entities and relations in the second phase.The two-phase paradigm enables our model to significantly reduce the data distribution gap,including the gap between negative entities and other entities,aswell as the gap between negative relations and other relations.In addition,we make the first attempt at combining entity type and entity distance as global features,which has proven effective,especially for the relation extraction.Experimental results on several datasets demonstrate that the span-based joint extraction model augmented with the two-phase paradigm and the global features consistently outperforms previous state-ofthe-art span-based models for the joint extraction task,establishing a new standard benchmark.Qualitative and quantitative analyses further validate the effectiveness the proposed paradigm and the global features. 展开更多
关键词 Joint extraction span-based named entity recognition relation extraction data distribution global features
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Exploring relations between city regions based on mobile phone data
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作者 汪烁枫 李志恒 +1 位作者 姜山 谢娜 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1799-1806,共8页
City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations b... City regions often have great diversity in form and function. To better understand the role of each region, the relations between city regions need to be carefully studied. In this work, the human mobility relations between regions of Shanghai based on mobile phone data is explored. By formulating the regions as nodes in a network and the commuting between each pair of regions as link weights, the distribution of nodes degree, and spatial structures of communities in this relation network are studied. Statistics show that regions locate in urban centers and traffic hubs have significantly larger degrees. Moreover, two kinds of spatial structures of communities are found. In most communities, nodes are spatially neighboring. However, in the communities that cover traffic hubs, nodes often locate along corridors. 展开更多
关键词 mobile phone data city relations community DEGREE
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Emotion recognition support system: Where physicians and psychiatrists meet linguists and data engineers 被引量:1
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作者 Peyman Adibi Simindokht Kalani +6 位作者 Sayed Jalal Zahabi Homa Asadi Mohsen Bakhtiar Mohammad Reza Heidarpour Hamidreza Roohafza Hassan Shahoon Mohammad Amouzadeh 《World Journal of Psychiatry》 SCIE 2023年第1期1-14,共14页
An important factor in the course of daily medical diagnosis and treatment is understanding patients’ emotional states by the caregiver physicians. However, patients usually avoid speaking out their emotions when exp... An important factor in the course of daily medical diagnosis and treatment is understanding patients’ emotional states by the caregiver physicians. However, patients usually avoid speaking out their emotions when expressing their somatic symptoms and complaints to their non-psychiatrist doctor. On the other hand, clinicians usually lack the required expertise(or time) and have a deficit in mining various verbal and non-verbal emotional signals of the patients. As a result, in many cases, there is an emotion recognition barrier between the clinician and the patients making all patients seem the same except for their different somatic symptoms. In particular, we aim to identify and combine three major disciplines(psychology, linguistics, and data science) approaches for detecting emotions from verbal communication and propose an integrated solution for emotion recognition support. Such a platform may give emotional guides and indices to the clinician based on verbal communication at the consultation time. 展开更多
关键词 Physician-Patient relations Emotions Verbal behavior LINGUISTICS PSYCHOLOGY data science
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Attribute Reduction in Interval and Set-Valued Decision Information Systems
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作者 Hong Wang Hong-Bo Yue Xi-E Chen 《Applied Mathematics》 2013年第11期1512-1519,共8页
In many practical situation, some of the attribute values for an object may be interval and set-valued. This paper introduces the interval and set-valued information systems and decision systems. According to the sema... In many practical situation, some of the attribute values for an object may be interval and set-valued. This paper introduces the interval and set-valued information systems and decision systems. According to the semantic relation of attribute values, interval and set-valued information systems can be classified into two categories: disjunctive (Type 1) and conjunctive (Type 2) systems. In this paper, we mainly focus on semantic interpretation of Type 1. Then, we define a new fuzzy preference relation and construct a fuzzy rough set model for interval and set-valued information systems. Moreover, based on the new fuzzy preference relation, the concepts of the significance measure of condition attributes and the relative significance measure of condition attributes are given in interval and set-valued decision information systems by the introduction of fuzzy positive region and the dependency degree. And on this basis, a heuristic algorithm for calculating fuzzy positive region reduction in interval and set-valued decision information systems is given. Finally, we give an illustrative example to substantiate the theoretical arguments. The results will help us to gain much more insights into the meaning of fuzzy rough set theory. Furthermore, it has provided a new perspective to study the attribute reduction problem in decision systems. 展开更多
关键词 INTERVAL and set-valued INFORMATION SYSTEMS FUZZY Preference relation INTERVAL and set-valued DECISION INFORMATION SYSTEMS FUZZY Positive Region Dependency Degree Significance Measure
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Development of Granular Fuzzy Relation Equations Based on a Subset of Data
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作者 Dan Wang Xiubin Zhu +2 位作者 Witold Pedycz Zhenhua Yu Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1416-1427,共12页
Developing and optimizing fuzzy relation equations are of great relevance in system modeling,which involves analysis of numerous fuzzy rules.As each rule varies with respect to its level of influence,it is advocated t... Developing and optimizing fuzzy relation equations are of great relevance in system modeling,which involves analysis of numerous fuzzy rules.As each rule varies with respect to its level of influence,it is advocated that the performance of a fuzzy relation equation is strongly related to a subset of fuzzy rules obtained by removing those without significant relevance.In this study,we establish a novel framework of developing granular fuzzy relation equations that concerns the determination of an optimal subset of fuzzy rules.The subset of rules is selected by maximizing their performance of the obtained solutions.The originality of this study is conducted in the following ways.Starting with developing granular fuzzy relation equations,an interval-valued fuzzy relation is determined based on the selected subset of fuzzy rules(the subset of rules is transformed to interval-valued fuzzy sets and subsequently the interval-valued fuzzy sets are utilized to form interval-valued fuzzy relations),which can be used to represent the fuzzy relation of the entire rule base with high performance and efficiency.Then,the particle swarm optimization(PSO)is implemented to solve a multi-objective optimization problem,in which not only an optimal subset of rules is selected but also a parameterεfor specifying a level of information granularity is determined.A series of experimental studies are performed to verify the feasibility of this framework and quantify its performance.A visible improvement of particle swarm optimization(about 78.56%of the encoding mechanism of particle swarm optimization,or 90.42%of particle swarm optimization with an exploration operator)is gained over the method conducted without using the particle swarm optimization algorithm. 展开更多
关键词 A subset of data granular fuzzy relation equations interval-valued fuzzy relation particle swarm optimization(PSO)
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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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Research of storage technique for C-Temporal Relation Data Model
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作者 (Dept. of Computer & Engineering, Guangxi University of Technology, Guangxi Liuzhou 645006, China) WANG Zhi-wen (Mechanical Engineering College, Guangxi University, 530004, NanNin China )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 co... 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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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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