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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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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 on the Mapping Technology of CIM and Relational Database in Power Grid
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作者 赵婉婷 王滨 《科技信息》 2011年第7期222-223,共2页
With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data mainten... With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data maintenance uniform",and effectively eliminate "island of information",a standard,open information model of power system should be followed urgently by different systems,and a common data interface should be provided.The Common Information Model(CIM) proposed by standard of IEC-61970 solve the problem effectively.The characteristics of the CIM Model and relational database of power system are analyzed,a mapping method between CIM model based on standard of IEC61970 and relational database is proposed,and corresponding problems between object-oriented model and the relational model are solved flexiblely. 展开更多
关键词 数据库 CIM GIS 地理信息系统
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Computer Administering of the Psychological Investigations: Set-Relational Representation
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作者 Krasimir Yordzhev Ivelina Peneva 《Open Journal of Applied Sciences》 2012年第2期110-114,共5页
Computer administering of a psychological investigation is the computer representation of the entire procedure of psychological assessments—test construction, test implementation, results evaluation, storage and main... Computer administering of a psychological investigation is the computer representation of the entire procedure of psychological assessments—test construction, test implementation, results evaluation, storage and maintenance of the developed database, its statistical processing, analysis and interpretation. A mathematical description of psychological assessment with the aid of personality tests is discussed in this article. The set theory and the relational algebra are used in this description. A relational model of data, needed to design a computer system for automation of certain psychological assessments is given. Some finite sets and relation on them, which are necessary for creating a personality psychological test, are described. The described model could be used to develop real software for computer administering of any psychological test and there is full automation of the whole process: test construction, test implementation, result evaluation, storage of the developed database, statistical implementation, analysis and interpretation. A software project for computer administering personality psychological tests is suggested. 展开更多
关键词 COMPUTER Administering COMPUTER Testing COMPUTER Psycho DIAGNOSTIC Mathematical modeling SET Theory relational algebra databaseS
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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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Extending the Relational Model to Deal withProbabilistic Data
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作者 马宗民 ZHANG W.J MA W.Y 《Journal of Computer Science & Technology》 SCIE EI CSCD 2000年第3期230-240,共11页
According to the soundness and completeness of information in databases, the expressive form and the semantics of incomplete information are discussed in this paper. On the basis of the discussion, the current studies... According to the soundness and completeness of information in databases, the expressive form and the semantics of incomplete information are discussed in this paper. On the basis of the discussion, the current studies on incomplete data in relational databases are reviewed. In order to represent stochastic uncertainty in most general sense in the real world, probabilistic data are introduced into relational databases. An extended relational data model is presented to express and manipulate probabilistic data and the operations in relational algebra based on the extended model are defined in this paper. 展开更多
关键词 incomplete information uncertain information extended relational model probabilistic data relational algebra
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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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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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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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Query Languages for Temporal Database
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作者 邓培民 《High Technology Letters》 EI CAS 1997年第2期47-51,共5页
In this paper, an interval-gap-based 1NF temporal tuple calculus language and the corresponding temporal relation algebra are established on the basis of considering the trouble of stack operations in both S. Gadia’s... In this paper, an interval-gap-based 1NF temporal tuple calculus language and the corresponding temporal relation algebra are established on the basis of considering the trouble of stack operations in both S. Gadia’s TCAL and temporal tuple calculus due to their NINF. 展开更多
关键词 TEMPORAL database SQL TEMPORAL relatION algebra TUPLE CALCULUS QUERY language
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一种基于对象关系模型的时空查询代数stor-algebra 被引量:1
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作者 周英华 金培权 +1 位作者 岳丽华 龚育昌 《中国科学技术大学学报》 CAS CSCD 北大核心 2006年第11期1190-1195,1201,共7页
通过对目前已有的时空数据库技术在易于实现的时空查询代数方面进行的深入研究,提出了一种基于对象关系的时空查询代数stor-algebra,从数据结构和代数操作两方面进行了详细描述.stor-algebra兼容关系代数,并可在对象关系数据库管理系统... 通过对目前已有的时空数据库技术在易于实现的时空查询代数方面进行的深入研究,提出了一种基于对象关系的时空查询代数stor-algebra,从数据结构和代数操作两方面进行了详细描述.stor-algebra兼容关系代数,并可在对象关系数据库管理系统上实现,可作为时空查询处理系统的代数基础. 展开更多
关键词 时空数据库 查询代数 对象关系数据库
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支持网络建模和仿真的Modelica模型管理框架
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作者 周佳玲 熊体凡 万立 《计算机辅助工程》 2013年第4期71-75,共5页
为解决基于Modelica的仿真模型组织方式不能支持模型网络化共享控制和网络环境下在线建模和仿真的问题,采用数据库与文件仓相结合的方法重构Modelica模型组织方式,开发用户界面、模型管理服务和模型库,形成网络模型管理框架.基于该模型... 为解决基于Modelica的仿真模型组织方式不能支持模型网络化共享控制和网络环境下在线建模和仿真的问题,采用数据库与文件仓相结合的方法重构Modelica模型组织方式,开发用户界面、模型管理服务和模型库,形成网络模型管理框架.基于该模型管理框架开发实现基于网络的多领域统一建模和仿真平台,可以有效支持用户网页可视化建模和仿真以及模型网络存储共享. 展开更多
关键词 多领域统一建模和仿真 知识模型库 网络环境 关系数据库 modelICA
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Scientific articles recommendation with topic regression and relational matrix factorization
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作者 Ming YANG Ying-ming LI Zhongfei(Mark) ZHANG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2014年第11期984-998,共15页
In this paper we study the problem of recommending scientific articles to users in an online community with a new perspective of considering topic regression modeling and articles relational structure analysis simulta... In this paper we study the problem of recommending scientific articles to users in an online community with a new perspective of considering topic regression modeling and articles relational structure analysis simultaneously. First, we present a novel topic regression model, the topic regression matrix factorization (tr-MF), to solve the problem. The main idea of tr-MF lies in extending the matrix factorization with a probabilistic topic modeling. In particular, tr-MF introduces a regression model to regularize user factors through probabilistic topic modeling under the basic hypothesis that users share similar preferences if they rate similar sets of items. Consequently, tr-MF provides interpretable latent factors for users and items, and makes accurate predictions for community users. To incorporate the relational structure into the framework of tr-MF, we introduce relational matrix factorization. Through combining tr-MF with the relational matrix femtorization, we propose the topic regression collective matrix factorization (tr-CMF) model. In addition, we also present the collaborative topic regression model with relational matrix factorization (CTR-RMF) model, which combines the existing collaborative topic regression (CTR) model and relational matrix factorization (RMF). From this point of view, CTR-RMF can be considered as an appropriate baseline for tr-CMF. Further, we demonstrate the efficacy of the proposed models on a large subset of the data from CiteULike, a bibliography sharing service dataset. The proposed models outperform the state-of-the-art matrix factorization models with a significant margin. Specifically, the proposed models are effective in making predictions for users with only few ratings or even no ratings, and support tasks that are specific to a certain field, neither of which has been addressed in the existing literature. 展开更多
关键词 Matrix factorization probabilistic topic modeling relational matrix factorization Rccommender system
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SQL3 Object Model and Its Extension
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作者 ZHUANGJi-feng PENGZhi-yong 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期681-686,共6页
As the latest version of relational database standard, SQL3 not only has been extended with many new relational features but also added with the object-oriented technologies. This paper introduces the object-oriented ... As the latest version of relational database standard, SQL3 not only has been extended with many new relational features but also added with the object-oriented technologies. This paper introduces the object-oriented features of SQL3 and then extends it with object deputy model to support object view mechanisms. Key words SQL3 - object-relational database - object deputy model - inheritance CLC number TP 392 Foundation item: Supported by the National Natural Science Foundation of China (60273072), 863 Foundation of China (2002AA4Z3450), Research Fund for the Doctoral Program of Higher Education(20010486029) and Hubei Natural Science Fund for Distinguished Youth(2002AC003)Biography: ZHUANG Ji-feng (1979-), male, Master, research direction: database theory. 展开更多
关键词 SQL3 object-relational database object deputy model INHERITANCE
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关于将类图映射成关系表的策略研究
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作者 李娟 明德廷 王兴宇 《现代信息科技》 2024年第1期113-115,120,共4页
文章研究了类图映射成关系数据库中的表的策略,首先使用Rational Rose 7.0建立类图数据模型,通过给类设置不同的可见性,并在类图中使用类与类之间的各种关系,然后再探讨了类图映射成关系表的规律。实践的结果表明,将类图映射成关系数据... 文章研究了类图映射成关系数据库中的表的策略,首先使用Rational Rose 7.0建立类图数据模型,通过给类设置不同的可见性,并在类图中使用类与类之间的各种关系,然后再探讨了类图映射成关系表的规律。实践的结果表明,将类图映射成关系数据库中的表取决于两个因素,即类的可见性和类与类之间的关系,并发现RationalRose7.0软件没有考虑到当属性可见性不同时映射成表中对应的属性也应该是不同的。 展开更多
关键词 可视化建模 类图 关系数据库
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基于生物信息学构建口腔鳞状细胞癌免疫基因的预后模型 被引量:1
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作者 王锦航 彭士雄 +2 位作者 杨凯成 陈彦平 崔子峰 《疑难病杂志》 CAS 2024年第1期78-85,共8页
目的旨在构建免疫相关基因(IRGs)的风险预测模型,以预测口腔鳞状细胞癌(OSCC)患者的预后。方法应用生物信息学技术分析OSCC的转录组测序数据,鉴定出差异表达的IRGs(DEIRGs)。通过Cox回归分析构建DEIRGs的风险预测模型,并对其预测能力进... 目的旨在构建免疫相关基因(IRGs)的风险预测模型,以预测口腔鳞状细胞癌(OSCC)患者的预后。方法应用生物信息学技术分析OSCC的转录组测序数据,鉴定出差异表达的IRGs(DEIRGs)。通过Cox回归分析构建DEIRGs的风险预测模型,并对其预测能力进行评估。分析该模型与临床病理和免疫细胞浸润的相关性。结果通过比较OSCC和正常样本共鉴定出3634个差异表达基因,其中包括330个DEIRGs(FDR<0.05,|logFC|>1)。单因素Cox回归分析筛选出与预后相关的20个DEIRGs(P<0.05),多因素Cox回归分析筛选出其中15个DEIRGs用于构建风险预测模型。该模型可作为OSCC患者的独立预后因素(P<0.001),预测患者预后的能力具有较高的准确性(AUC=0.732),并与临床分期(t=-3.484,P<0.001)、B细胞(Cor=-0.180,P=0.002)和CD4^(+)T细胞(Cor=-0.127,P=0.026)密切相关。结论基于15个预后相关DEIRGs构建的风险预测模型能够有效地预测OSCC患者的预后,可帮助临床医生为不同风险的OSCC患者选择个性化的治疗策略。 展开更多
关键词 口腔鳞状细胞癌 免疫相关基因 预后 风险预测模型 癌症基因组图谱数据库
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基于TCGA数据库肺腺癌衰老相关基因预后模型的建立与验证 被引量:1
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作者 邢龙 吴双丽 +4 位作者 吴铁成 徐敬宣 李保健 田平 李醒亚 《海南医学》 CAS 2024年第10期1374-1379,共6页
目的探究肺腺癌(LUAD)差异表达的衰老相关基因(ARGs),并构建LUAD衰老相关基因的预后模型。方法LUAD的RNA高通量转录组数据下载于癌症基因组图谱(TCGA)数据库,AgingAtlas数据库获取ARGs,并基于LUAD中衰老相关差异表达基因构建LUAD预后模... 目的探究肺腺癌(LUAD)差异表达的衰老相关基因(ARGs),并构建LUAD衰老相关基因的预后模型。方法LUAD的RNA高通量转录组数据下载于癌症基因组图谱(TCGA)数据库,AgingAtlas数据库获取ARGs,并基于LUAD中衰老相关差异表达基因构建LUAD预后模型并验证,进一步构建列线图及校准曲线探究模型在临床中的应用价值。结果通过韦恩图去交集共获得80个衰老相关差异表达基因。通过单因素、多因素Cox回归分析筛选得到7个具有独立预后意义的差异表达ARGs,对筛选出的7个基因进行LASSO回归分析并构建LUAD预后模型。构建Kaplan-Meier生存曲线显示,与低风险组相比,高风险组与较差的OS显著相关,差异具有统计学意义(P<0.05)。1、3和5年受试者操作特性(ROC)曲线下面积(AUC)分别为0.706、0.725、0.642,提示风险模型有较高的灵敏度和特异度。单因素及多因素Cox回归显示,风险评分为LUAD独立预后因素。进一步基于风险评分构建列线图及校准曲线,校准曲线列线图全局的一致性为0.729,说明该模型预测结果与实际情况有较高的准确度。结论基于差异表达的ARGs构建的风险模型可作为LUAD的一种预后特征,为LUAD患者个体化治疗提供参考。 展开更多
关键词 衰老基因 肺腺癌 预后模型 TCGA数据库 生物信息学
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基于贝叶斯网和RoBERTa的文本派生关系挖掘方法
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作者 庄园 翁年凤 李杰 《计算机工程与设计》 北大核心 2024年第9期2690-2696,共7页
对不实信息进行溯源分析是抑制社交网络中不实信息传播的重要手段,传统数据溯源方法主要针对结构化数据,难以准确判断文本之间的派生关系。针对这些问题,提出一种基于贝叶斯网和RoBERTa的文本派生关系挖掘方法,通过RoBERTa模型获得文本... 对不实信息进行溯源分析是抑制社交网络中不实信息传播的重要手段,传统数据溯源方法主要针对结构化数据,难以准确判断文本之间的派生关系。针对这些问题,提出一种基于贝叶斯网和RoBERTa的文本派生关系挖掘方法,通过RoBERTa模型获得文本向量;通过RoBERTa模型初步预测文本间的派生关系,得到文本是否具有派生关系的分类标签;基于向量距离、文本距离、时间跨度和文本分类标签构建贝叶斯网,对文本派生关系进行判断。实验结果表明,所提方法查准率、查全率、F 1值均高于对比方法,验证了该方法的有效性。 展开更多
关键词 数据溯源 文本派生 贝叶斯网 预训练语言模型 派生关系 文本距离 概率模型
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焦亡相关基因与胃癌预后及免疫浸润的相关性分析
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作者 吴云青 王承霞 谢东宇 《中国医药导报》 CAS 2024年第21期35-45,共11页
目的通过生物信息学筛选胃癌预后焦亡相关基因(PRGs),构建和评估风险模型并分析PRGs与免疫浸润的相关性,验证胃癌治疗的新靶点。方法从癌症基因组图谱(TCGA)数据库获取胃癌的转录组和临床数据并筛选差异表达的PRGs。采用单因素Cox回归及... 目的通过生物信息学筛选胃癌预后焦亡相关基因(PRGs),构建和评估风险模型并分析PRGs与免疫浸润的相关性,验证胃癌治疗的新靶点。方法从癌症基因组图谱(TCGA)数据库获取胃癌的转录组和临床数据并筛选差异表达的PRGs。采用单因素Cox回归及LASSO回归分析差异表达的PRGs并构建预后模型。Kaplan-Meier生存曲线、受试者操作特征曲线评估模型的准确性及预后价值。根据风险评分中位数将患者分为高、低风险组,Cox回归风险模型评估风险评分与预后的相关性。胃癌基因芯片数据集GSE84437作为预测模型的外部验证。RT-qPCR和Western blot检测SERPINE1、Caspase-1、NLRP3 mRNA和蛋白表达量。结果筛选35个差异表达PRGs,其中5个PRGs(CRTAC1、GPX3、IRGM、RGS2和SERPINE1)被纳入风险模型构建。年龄、M分期、N分期和风险评分是TCGA队列患者生存率的独立影响因素(P<0.05);年龄、T分期和N分期是基因表达综合(GEO)队列患者生存率的独立影响因素(P<0.05)。TCGA、GEO队列中高风险组免疫细胞浸润水平、免疫相关途径活性总体均高于低风险组(P<0.05)。CRTAC1与CD4+T细胞(r=0.488)、巨噬细胞(r=0.588)和树突状细胞(r=0.332)的浸润水平呈正相关(P<0.01);GPX3与CD4+T细胞(r=0.372)、巨噬细胞(r=0.572)和树突状细胞(r=0.406)的浸润水平呈正相关(P<0.01);RGS2与CD4+T细胞(r=0.343)、巨噬细胞(r=0.526)和树突状细胞(r=0.326)的浸润水平呈正相关(P<0.01);IRGM(r=0.327)、SERPINE1(r=0.310)与巨噬细胞的浸润水平呈正相关(P<0.01)。胃癌组织中SERPINE1表达水平高于正常胃组织(P<0.05);高表达SERPINE1组的生存时间短于低表达SERPINE1组(P<0.01)。干扰组SERPINE1、Caspase-1、NLRP3 mRNA和蛋白表达量均低于阴性对照组(P<0.05)。结论通过生物信息学方法筛选5个PRGs构建胃癌预后模型,SERPINE1高表达与胃癌不良预后相关,可能参与调控NLRP3/Caspase-1细胞焦亡途径。 展开更多
关键词 胃癌 焦亡相关基因 癌症基因组图谱数据库 预后风险模型 免疫浸润
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基于工业基础类标准的建筑信息模型数据交互及应用 被引量:1
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作者 程可 戴成元 +2 位作者 梁邦勋 邹敏 刘其舟 《科学技术与工程》 北大核心 2024年第9期3797-3803,共7页
针对当前工业类基础(industry foundation classes,IFC)标准文件的开发应用存在文件格式转换繁杂、数据互操作性弱及信息有效利用率低等问题,提出一种IFC模型数据映射至数据库、建筑信息模型(building information modeling,BIM)在Web... 针对当前工业类基础(industry foundation classes,IFC)标准文件的开发应用存在文件格式转换繁杂、数据互操作性弱及信息有效利用率低等问题,提出一种IFC模型数据映射至数据库、建筑信息模型(building information modeling,BIM)在Web端重构及信息在线可视化分析的实施方法。基于Web框架,搭建IFC标准文件映射至关系型数据库的应用框架。该应用框架利用JavaScript语言对IFC标准文件深度解析,采用Python语言将IFC模型数据和建筑全生命周期有效信息储存至关系型数据库,结合实际案例及分析,展现并验证该应用框架的实施效果。结果表明:该方法可实现项目数据交互的完整性和高效性,支持建筑全生命周期相关应用的二次开发;同时融合智能建造技术和科学管理,提升BIM信息管理的有效性,促进建筑业数字化发展和智能化应用拓展。 展开更多
关键词 建筑信息模型(BIM) 工业类基础(IFC) WEBGL 关系型数据库 可视化
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