In the engineering database system, multiple versions of a design including engineering drawings should be managed efficiently. The paper proposes an efficient spatial data structure, that is an expansion of the R tre...In the engineering database system, multiple versions of a design including engineering drawings should be managed efficiently. The paper proposes an efficient spatial data structure, that is an expansion of the R tree and HR tree, for version management of engineering drawings. A novel mechanism to manage the difference between drawings is introduced to the HR tree to eliminate redundant duplications and to reduce the amount of storage required for the data structure. Data management mechanism and structural properties of our data structure called the MVR + tree are described.展开更多
Since the late of previous decade, hypertext technique has been applied in many areas. A hypertext data model with version control which is applied to a digital delivery for engineering documents named Optical Disk ba...Since the late of previous decade, hypertext technique has been applied in many areas. A hypertext data model with version control which is applied to a digital delivery for engineering documents named Optical Disk based Electronic Archives Management System(ODEAMS) is presented first and it has successfully solved some problems in engineering data management. Then, this paper describes some details to implement the hypertext network in ODEAMS after introducing the requirements and characters of engineering data management.展开更多
A version of a product consists of the product structure tree and the versions of all its components. The model includes two sets of data： attributes and documents describing each component. The paper discusses the v...A version of a product consists of the product structure tree and the versions of all its components. The model includes two sets of data： attributes and documents describing each component. The paper discusses the version change relations between a sub-node component and a up-node component in a product structure tree, analyzes the version control system for a static reference and that for a dynamic reference and proposes a product structure model in support of dynamic reference, which is easy to use and contains a complete set of information providing an essential way of data organization for the PDM system.展开更多
目的探讨基于双参数磁共振成像(biparametric magnetic resonance imaging,bp-MRI)的前列腺影像报告和数据系统2.1版(prostate imaging report and data system version 2.1,PI-RADS v2.1)联合前列腺特异性抗原密度(prostate specific a...目的探讨基于双参数磁共振成像(biparametric magnetic resonance imaging,bp-MRI)的前列腺影像报告和数据系统2.1版(prostate imaging report and data system version 2.1,PI-RADS v2.1)联合前列腺特异性抗原密度(prostate specific antigen density,PSAD)鉴别诊断总前列腺特异性抗原(total prostate specific antigen,tPSA)4~20 ng/mL临床显著性前列腺癌(clinically significant prostate cancer,csPCa)的价值及风险分层。材料与方法回顾性分析了宁夏医科大学总医院2017年10月至2023年6月304例PSA 4~20 ng/mL前列腺疾病患者的bp-MRI图像和临床资料。根据病理结果分为csPCa组(Gleason评分≥7分,n=66)和非csPCa(Gleason评分<7分及良性疾病,n=238)。经单因素、多因素logistic回归分析筛选独立危险因子并建立联合模型,再用决策曲线分析(decision curve analysis,DCA)其临床净效益。以受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)比较独立危险因子与联合模型的诊断效能,并对独立危险因子进行等级划分和组合。结果联合模型(PI-RADS v2.1+PSAD)的诊断效能最好(AUC为0.901,95%CI:0.858~0.944)。将PI-RADS v2.1与PSAD等级划分并组合,当PI-RADS v2.1≤2且PSAD≤0.15 ng/mL^(2),csPCa阳性率为0%;当PI-RADS v2.1为3分且PSAD<0.30 ng/mL^(2)时,csPCa阳性率<15%;当PI-RADS v2.1为4~5分且PSAD为0.15~0.29 ng/mL^(2)时,csPCa阳性率为46.5%;当PI-RADS v2.1为4~5分且PSAD≥0.30 ng/mL^(2)时,csPCa阳性率高达81.3%。结论PI-RAD v2.1≤2或PI-RAD v2.1=3且PSAD值<0.30 ng/ml2的患者可避免不必要的活检。PI-RADS v2.1联合PSAD能显著提高tPSA 4~20 ng/mL csPCa的诊断效能,将二者联合有助于穿刺前对csPCa的患者进行风险评估,以减少部分患者不必要的穿刺,并为临床提供一定的决策指导。展开更多
以1∶10000 DLG和0.5 m DOM数据为研究对象,开展公众版测绘成果加工和编制技术研究,探索公众版测绘成果基础矢量数据、基础影像数据及公开版地形图加工和编制技术路线。拓展公众版测绘成果(产品)种类和格式,提高数据产品的现势性,推进...以1∶10000 DLG和0.5 m DOM数据为研究对象,开展公众版测绘成果加工和编制技术研究,探索公众版测绘成果基础矢量数据、基础影像数据及公开版地形图加工和编制技术路线。拓展公众版测绘成果(产品)种类和格式,提高数据产品的现势性,推进保密处理技术的应用,为广泛开展公众版测绘成果加工和编制提供可借鉴的经验。展开更多
文摘In the engineering database system, multiple versions of a design including engineering drawings should be managed efficiently. The paper proposes an efficient spatial data structure, that is an expansion of the R tree and HR tree, for version management of engineering drawings. A novel mechanism to manage the difference between drawings is introduced to the HR tree to eliminate redundant duplications and to reduce the amount of storage required for the data structure. Data management mechanism and structural properties of our data structure called the MVR + tree are described.
文摘Since the late of previous decade, hypertext technique has been applied in many areas. A hypertext data model with version control which is applied to a digital delivery for engineering documents named Optical Disk based Electronic Archives Management System(ODEAMS) is presented first and it has successfully solved some problems in engineering data management. Then, this paper describes some details to implement the hypertext network in ODEAMS after introducing the requirements and characters of engineering data management.
基金Supported by the Fundamental Fujian Nature Science (A0440006) and Xiamen Science & Technology Project (3502Z20055028)
文摘A version of a product consists of the product structure tree and the versions of all its components. The model includes two sets of data： attributes and documents describing each component. The paper discusses the version change relations between a sub-node component and a up-node component in a product structure tree, analyzes the version control system for a static reference and that for a dynamic reference and proposes a product structure model in support of dynamic reference, which is easy to use and contains a complete set of information providing an essential way of data organization for the PDM system.
文摘以1∶10000 DLG和0.5 m DOM数据为研究对象,开展公众版测绘成果加工和编制技术研究,探索公众版测绘成果基础矢量数据、基础影像数据及公开版地形图加工和编制技术路线。拓展公众版测绘成果(产品)种类和格式,提高数据产品的现势性,推进保密处理技术的应用,为广泛开展公众版测绘成果加工和编制提供可借鉴的经验。
