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Feature-based and objectoriented product information model for welding structure
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作者 林三宝 杨春利 +1 位作者 黎明 吴林 《China Welding》 EI CAS 1999年第2期3-10,共8页
Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequen... Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequent manufacturing activities such as CAPP and CAM. A new design approach using feature technique and object oriented programming method is put forward in this paper in order to create the product information model of welding structure. With this approach, the product information model is able to effectively support computer aided welding process planning, fixturing, assembling, path planning of welding robot and other manufacturing activities. The feature classification and representing scheme of welding structure are discussed. A prototype system is developed based on feature and object oriented programming. Its structure and functions are given in detail. 展开更多
关键词 object oriented programming feature based design product information model welding structure CAD/CAM integration
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Modeling Method of Automotive Body CAN/LIN Nets Application Protocol Based on Object-oriented Colored Petri Net 被引量:8
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作者 FANG Hua HAN Jianghong and LIU Xiaoping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第6期999-1006,共8页
Recently automotive nets are adopted to solve increasing problems in automotive electronic systems.Technologies of automotive local area network from CAN and LIN can solve the problems of the increasing of wire bunch ... Recently automotive nets are adopted to solve increasing problems in automotive electronic systems.Technologies of automotive local area network from CAN and LIN can solve the problems of the increasing of wire bunch weight and lack in module installation space.However,the multilayer automotive nets software becomes more and more complex,and the development expense is difficult to predict and to keep in check.In this paper,the modeling method of hierarchical automotive nets and the substitution operation based on object-oriented colored Petri net(OOCPN) are proposed.The OOCPN model which analyzes the software structure and validates the collision mechanism of CAN/LIN bus can speed the automobile system development.First,the subsystems are divided and modeled by object-oriented Petri net(OOPN).According to the sets of message sharing relations,the message ports among them are set and the communication gate transitions are defined.Second,the OOPN model is substituted step by step until the inner objects in the automotive body control modules(BCM) are indivisible and colored by colored Petri net(CPN).And the color subsets mark the node messages for the collision mechanism.Third,the OOCPN model of the automotive body CAN/LIN nets is assembled,which keeps the message sets and the system can be expanded.The proposed model is used to analyze features of information sharing among the objects,and it is also used to describe each subsystem real-time behavior of processing messages and implemental device controllers operating,and puts forward a reasonable software framework for the automotive body control subsystem.The research can help to design the communication model in the automotive body system effectively and provide a convenient and rapid way for developing the logical hierarchy software. 展开更多
关键词 automotive body CAN/LIN bus information sharing object-oriented colored Petri net modeling
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The Feature-Based a New Object Coding Approach for Prismatic Parts at the Part Modeling
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作者 Ismet Celik Ali Unuvar 《Modeling and Numerical Simulation of Material Science》 2013年第4期129-138,共10页
Use of features in order to achieve the integration of design and manufacture has been considered to be a key factor recent years. Features such as manufacturing properties form the workpiece. Features are structured ... Use of features in order to achieve the integration of design and manufacture has been considered to be a key factor recent years. Features such as manufacturing properties form the workpiece. Features are structured systematically through object oriented modeling. This article explains an object coding method developed for prismatic workpieces and the use of that method in process planning. Features have been determined and modeled as objects. Features have been coded according to their types and locations on the workpiece in this given method. Feature codings have been seen to be very advantageous in process planning. 展开更多
关键词 feature feature based modeling object oriented modeling Process Planning
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An Approach to Detect Structural Development Defects in Object-Oriented Programs
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作者 Maxime Seraphin Gnagne Mouhamadou Dosso +1 位作者 Mamadou Diarra Souleymane Oumtanaga 《Open Journal of Applied Sciences》 2024年第2期494-510,共17页
Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detecti... Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detection approaches, ranging from traditional heuristic algorithms to machine learning methods, are used to identify these defects. Ensemble learning methods have strengthened the detection of these defects. However, existing approaches do not simultaneously exploit the capabilities of extracting relevant features from pre-trained models and the performance of neural networks for the classification task. Therefore, our goal has been to design a model that combines a pre-trained model to extract relevant features from code excerpts through transfer learning and a bagging method with a base estimator, a dense neural network, for defect classification. To achieve this, we composed multiple samples of the same size with replacements from the imbalanced dataset MLCQ1. For all the samples, we used the CodeT5-small variant to extract features and trained a bagging method with the neural network Roberta Classification Head to classify defects based on these features. We then compared this model to RandomForest, one of the ensemble methods that yields good results. Our experiments showed that the number of base estimators to use for bagging depends on the defect to be detected. Next, we observed that it was not necessary to use a data balancing technique with our model when the imbalance rate was 23%. Finally, for blob detection, RandomForest had a median MCC value of 0.36 compared to 0.12 for our method. However, our method was predominant in Long Method detection with a median MCC value of 0.53 compared to 0.42 for RandomForest. These results suggest that the performance of ensemble methods in detecting structural development defects is dependent on specific defects. 展开更多
关键词 object-oriented Programming Structural Development Defect Detection Software Maintenance Pre-Trained models features Extraction BAGGING Neural Network
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A FEATURE-BASED PRODUCT MODELLING SYSTEM ON PC (CASE STUDY OF PARTS DESIGN FOR PRESS MACHINE)
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作者 Yonas Hagos Tong Bingshu 《Computer Aided Drafting,Design and Manufacturing》 1996年第1期48-57,共2页
This article reports on the design and implementation of feature modelling system for the CAPP of rotational symmetric components. The work deals with design by features, feature parts database design, and parts infor... This article reports on the design and implementation of feature modelling system for the CAPP of rotational symmetric components. The work deals with design by features, feature parts database design, and parts information modelling techniques realized in Personal Computer. The modular software provides utilities such as interactive component synthesis, dimensioning, tolerancing and graphical display. 展开更多
关键词 ss: feature feature based design CAPP part information model
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Extended Object Model for Product Configuration Design 被引量:4
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作者 Zhi-Wei Xu Ze-Zhong Liang Zhong-Qi Sheng 《International Journal of Automation and computing》 EI 2010年第3期289-294,共6页
This paper presents an extended object model for case-based reasoning (CBR) in product configuration design. In the extended object model, a few methods of knowledge expression are adopted, such as constraints, rule... This paper presents an extended object model for case-based reasoning (CBR) in product configuration design. In the extended object model, a few methods of knowledge expression are adopted, such as constraints, rules, objects, etc. On the basis of extended object model, case representation model for CBR is applied to product configuration design system. The product configuration knowledge can be represented by the extended object. The model can support all the processes of CBR in product configuration design, such as case representation, indexing, retrieving, and case revising. The presented model is an extension of the traditional object-oriented model by including the relationship class used to express the relation between the cases, constraints class used in the product configuration knowledge representation, index class used in ease retrieving, and solution class used in case revising. Therefore, the product configuration knowledge used in the product configuration design can be represented by using this model. In the end, a metering pump product configuration design system is developed on the basis of the proposed product configuration model to support customized products. 展开更多
关键词 Mass customization product configuration case-based reasoning (CBR) object-oriented modeling case representation.
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AN INTEGRATED DATA MODEL IN THREE DIMENSIONAL GIS 被引量:2
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作者 Gong Jianya Xia Zongguo 《Geo-Spatial Information Science》 1999年第1期1-8,15,共9页
The current GIS can only deal with 2-D or 2.5-D information on the earth surface. A new 3-D data structure and data model need to be designed for the 3-D GIS. This paper analyzes diverse 3-D spatial phenomena from min... The current GIS can only deal with 2-D or 2.5-D information on the earth surface. A new 3-D data structure and data model need to be designed for the 3-D GIS. This paper analyzes diverse 3-D spatial phenomena from mine to geology and their complicated relations, and proposes several new kinds of spatial objects including cross-section, column body and digital surface model to represent some special spatial phenomena like tunnels and irregular surfaces of an ore body. An integrated data structure including vector, raster and object-oriented data models is used to represent various 3-D spatial objects and their relations. The integrated data structure and object-oriented data model can be used as bases to design and realize a 3-D geographic information system. 展开更多
关键词 3-D GEOGRAPHIC information system object-oriented data model VECTOR RASTER
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SEMANTIC CONSTRAINT MODELER FOR 2D AND 3D GEOMETRY
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作者 JIAO Guofang LIU Shenquan CAD Lab.,Institute of Computing Technology Academia Sinica,Beijing 100080,P.R.China 《Computer Aided Drafting,Design and Manufacturing》 1992年第1期46-57,共12页
Design changes for 2D & 3D geometry are the most important features in the process of product design.Constraint modeling for variationl geometry based on geometric reasoning is one of the best approaches for this ... Design changes for 2D & 3D geometry are the most important features in the process of product design.Constraint modeling for variationl geometry based on geometric reasoning is one of the best approaches for this goal.However,it is difficult for the proposed systems to maintain or handle the consistency and completeness of the constraint model of the design objects.To change this situation,a semantic model and its control approach are presented,aiming at the integration of the data,knowledge and method related to design objects.Aconstraint definition system for in- teractively defining the semantic model and a prototype modeler based on the semantic model are also implemented to examine the idea which is extended to 3D geometric design too. 展开更多
关键词 variational geometry constraint-based modeller semantic model object oriented knowledge representation
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A Kind of Object-Oriented Model Representation andthe MBMS 被引量:2
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作者 LUO Jian FU Rong(Department of Automation,Xiamen University,China 361005) 《Systems Science and Systems Engineering》 CSCD 1999年第2期237-243,共7页
According to the theory of Object Oriented analysis and design method, a kind ofrepresentation of model and the structure of the model base management system is presented, and therealization of the method is introduced.
关键词 model model-base management system object-oriented decision support system
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Modelling Enterprises with Object-Oriented Paradigm
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作者 顾君忠 《Journal of Computer Science & Technology》 SCIE EI CSCD 1993年第3期270-279,共10页
Modelling enterprises include two essential tasks:data modelling for static properties and behaviours modelling for dynamic properties.Traditionally,the data modelling and behaviours modelling are separated in differe... Modelling enterprises include two essential tasks:data modelling for static properties and behaviours modelling for dynamic properties.Traditionally,the data modelling and behaviours modelling are separated in different phases and also in different description forms,e.g.the former is modelled in entity-relationship diagrams(ERDs),and the latter is modelled in data flow diagrams (DFDs).The separation could result in an incorrect description of the relationships between da- ta and behaviours,so that the enterprise model couldn't reflect the actual conditions and demands of the enterprise.In this paper an object-oriented approach integrating data with behaviours in a model for the Enterprises Management Information Systems(in short,EMISs)is proposed.As an isomorphic mapping of enterprises an object-oriented model can,in a natural form,exactly describe the dynamic and static properties of enterprises in an integrated model.Therefore it can be easily used by the end-users(e.g.the experts in accounting,financial reporting,and business managers) to specify their demands and communicate with the system analysts and designers.Based on the model an EMIS can be prototyped quickly,and then be conveniently evolved with inheritance mechanism to an adaptive application system according to the actual demands of the enterprise. 展开更多
关键词 Enterprises Management information System(EMIS) object-system object-oriented system object-oriented modelling O-graph OO-graph OC-graph.
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应用无人机可见光影像和面向对象的随机森林模型对城市树种分类 被引量:2
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作者 陈逊龙 孙一铭 +4 位作者 郭仕杰 段煜柯 唐桉琦 叶章熙 张厚喜 《东北林业大学学报》 CAS CSCD 北大核心 2024年第3期48-59,共12页
为及时准确的了解城市树种空间分布信息,提升城市居民生活水平和推动城市生态系统可持续发展。以福州市仓山区城市森林为研究对象,应用无人机(UAV)监测城市树种空间分布及其动态变化的可见光影像,根据最佳尺度对影像进行分割,并提取分... 为及时准确的了解城市树种空间分布信息,提升城市居民生活水平和推动城市生态系统可持续发展。以福州市仓山区城市森林为研究对象,应用无人机(UAV)监测城市树种空间分布及其动态变化的可见光影像,根据最佳尺度对影像进行分割,并提取分割对象的光谱、地形、指数、纹理和几何特征。通过对不同类型特征的组合构建不同的分类方案,利用递归特征消除法(RFE)筛选出优选特征子集,利用面向对象方法结合随机森林(RF)模型对城市树种进行分类。结果表明:在随机森林模型分类的过程中,利用光谱特征对树种分类的总体分类精度为82.12%;地形特征对树种分类的贡献度率为14.96%;指数特征和纹理特征的引入,在一定程度提高了树种的分类精度;几何特征的贡献较小,在分类过程中没有明显的贡献。特征优选子集的S10方案分类精度最高,总体精度达92.42%,Kappa系数为0.91。说明特征优选能够降低高维度特征的复杂性,在大幅减少数据冗余的同时提高了分类精度。在最优特征子集下,随机森林(RF)算法分类的总体精度比极致梯度提升(XGBoost)、轻量级梯度提升机(LightGBM)和k最近邻算法(KNN)分别提高了1.15%、1.81%和15.15%,Kappa系数分别提高了1%、2%和17%。 展开更多
关键词 城市树种 无人机影像 面向对象 随机森林模型 地形特征
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基于GeoDataBase的面向对象的地质数据模型设计
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作者 王培忠 严卫东 +2 位作者 安斌 边辉 孙彬 《科技信息》 2008年第23期46-47,30,共3页
本文阐述建立基于GeoDataBase的地质教据模型的的方法,以1:50000中华人民共和国地质图所包含的地质内容为例,通过分析地质数据,划分要素类,定义和描述各要素类和关系类,最终利用Visio2003中建立完整的面向时象地质数据模型UML模型。由... 本文阐述建立基于GeoDataBase的地质教据模型的的方法,以1:50000中华人民共和国地质图所包含的地质内容为例,通过分析地质数据,划分要素类,定义和描述各要素类和关系类,最终利用Visio2003中建立完整的面向时象地质数据模型UML模型。由此模型使得地质资料数据的组织更为合理,使得地质数据库能够更好地服务于地质应用领域;同时,模型的研究也期望能为国土资源管理的信息化建设做一些有益的基础研究工作。 展开更多
关键词 GIS 面向对象 模型 要素类
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海洋保护地规划中生态系统模型的应用探究
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作者 孙润隆 赵林林 +3 位作者 庄鸿飞 曲方圆 王宗灵 张朝晖 《国家公园(中英文)》 2024年第3期176-184,共9页
海洋保护地是海洋生态环境管理的重要措施,科学有效的海洋保护地空间规划能够加强对海洋生物多样性和生态系统健康的保护。探讨面向对象的海洋生态系统评估(Object-oriented simulator of marine ecosystem exploitation,OSMOSE)模型在... 海洋保护地是海洋生态环境管理的重要措施,科学有效的海洋保护地空间规划能够加强对海洋生物多样性和生态系统健康的保护。探讨面向对象的海洋生态系统评估(Object-oriented simulator of marine ecosystem exploitation,OSMOSE)模型在海洋保护地空间规划中的应用前景,通过深入分析模型原理、关键过程和研究进展,以及结合模型特征及其功能实现,对模型在海洋保护地空间规划中能够发挥的多方面优势进行了重点探究;同时与现有海洋保护地空间规划方法的对比以及与实际海洋保护地案例结合,探讨了OSMOSE模型与现有的海洋保护地空间规划技术方法的异同及有机结合的潜在可能。结果表明,OSMOSE模型在模拟海洋生态系统动态、预测管理策略效果方面展现出的显著优势,模型对多物种相互作用以及时空分布的精准模拟,可以为海洋保护地空间规划提供丰富的数据支撑和决策依据。模型的合理应用不仅为我国海洋保护地建设提供了新视角,还有助于提升海洋保护地的空间规划合理性与管理措施有效性,对促进我国海洋生态保护具有重要作用和应用前景。 展开更多
关键词 海洋保护地 空间规划 生态系统模型 面向对象的海洋生态系统评估模型
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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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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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面向MBD模型的特征信息自动识别算法研究
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作者 郭亮 杨滔 +1 位作者 李湉 郑娟 《机械科学与技术》 CSCD 北大核心 2023年第9期1436-1444,共9页
针对特征识别技术对产品制造信息识别的缺失以及匹配算法的复杂性问题,提出了一种基于MBD模型的特征信息自动识别算法。首先,通过EXPRESS和Java映射,构建STEP文件解析器解析MBD模型信息。其次,建立基于图和提示的几何特征识别算法,用表... 针对特征识别技术对产品制造信息识别的缺失以及匹配算法的复杂性问题,提出了一种基于MBD模型的特征信息自动识别算法。首先,通过EXPRESS和Java映射,构建STEP文件解析器解析MBD模型信息。其次,建立基于图和提示的几何特征识别算法,用表征面邻接图作为匹配算法的数据结构,以提示作为搜索与特征库进行匹配。然后,提出基于关系树的产品制造信息识别方法识别产品制造信息。最后,以轴和机匣作为测试对象,在Intellij IDEA平台中对所提方法进行了验证,分析了匹配算法时间复杂度。结果表明,该方法能够识别几何特征信息和产品制造信息,本匹配算法时间复杂度为O(n),优于时间复杂度为O(n2)的传统匹配算法。 展开更多
关键词 MBD 产品制造信息 特征识别 图和提示
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基于区域感知的多尺度目标检测算法 被引量:1
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作者 黄路 李泽平 +2 位作者 杨文帮 赵勇 张嫡 《计算机工程》 CAS CSCD 北大核心 2023年第12期178-185,共8页
针对目标检测网络主分支层的特征信息易丢失、不同尺度的特征表达能力不平衡等问题,提出一种基于区域感知的多尺度目标检测算法。在YOLOv5的基础上采用数据增强、改进的边框损失和非极大值抑制方法,构建1个更强健的基线模型,沿着通道方... 针对目标检测网络主分支层的特征信息易丢失、不同尺度的特征表达能力不平衡等问题,提出一种基于区域感知的多尺度目标检测算法。在YOLOv5的基础上采用数据增强、改进的边框损失和非极大值抑制方法,构建1个更强健的基线模型,沿着通道方向使用全局最大池化、全局平均池化、卷积等操作设计通道信息增强模块,并分别作用于骨干网络的每个主分支层,使得各个检测头在特征融合过程中也不会丢失主分支层的关键特征,以强化模型对重点区域的感知能力。利用加权特征融合方法融合不同尺度的特征信息,平衡不同尺度的输入特征对输出特征的表达能力,进而提高模型对多尺度目标的感知能力,通过调整模型的通道和深度,设计4种不同规模的网络结构。实验结果表明,相比YOLOv5s,该算法在Pascal VOC、MS COCO、Global Wheat、Wider Face、Motor Defect 5个数据集上的平均精度均值分别提高5.48、3.00、1.94、0.70和1.95个百分点。同时,该算法的平均精度均值最高为50.7%,分别比YOLOv4和Dynamic Head的最大模型提高7.2和3.0个百分点。 展开更多
关键词 目标检测 增强基线模型 通道信息增强 加权特征融合 多尺度目标
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基于面向对象的吉林一号遥感影像湿地植被群落分类 被引量:2
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作者 谢文春 李强峰 +2 位作者 李艳春 吴振山 杨正凡 《林业资源管理》 北大核心 2023年第1期141-152,共12页
利用遥感技术提取湿地植被群落组成与分布,对湿地的建设具有重要意义。以青海乌兰都兰湖国家湿地公园为研究区,利用吉林一号遥感影像,通过影像分割,特征优化,选择KNN与RF分类模型,对都兰湖湿地植被群落进行划分,并验证分类精度。结果表... 利用遥感技术提取湿地植被群落组成与分布,对湿地的建设具有重要意义。以青海乌兰都兰湖国家湿地公园为研究区,利用吉林一号遥感影像,通过影像分割,特征优化,选择KNN与RF分类模型,对都兰湖湿地植被群落进行划分,并验证分类精度。结果表明,根据ESP 2工具提供的分割尺度,植被群落面向对象分类的最优分割尺度为18,植被与非植被区域分割尺度为32和85。地物类型划分方面,仅利用影像波段信息及相关指数的阈值不能精确提取地物类别,需要结合影像几何特征和纹理特征提高分类精度,利用特征空间优化工具对61个影像特征进行优化,最终筛选出了40个影像特征并用于分类。根据混淆矩阵分类精度评价结果,KNN算法分类结果优于RF,其中KNN总体分类精度为81.80%,Kappa系数为0.79;RF总体分类精度为72.59%,Kappa系数为0.68。根据分类结果,都兰湖湿地植被覆盖率为44.41%,植被群落的组成及分布特征可以为湿地生态建设及管理提供依据。 展开更多
关键词 都兰湖 植被群落分类 面向对象 影像特征 分类模型
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C++程序设计课程的混合式教学模式
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作者 高丽 《信息与电脑》 2023年第18期227-230,共4页
课程思政是新时代实现立德树人教育目标的重要举措,也是推动计算机类专业教学发展的有效途径。为解决计算机类相关专业课程的教学困境,帮助学生对编程类课程抽象理论内容的理解,提出思政背景下的C++程序设计课程混合式教学模式。实践证... 课程思政是新时代实现立德树人教育目标的重要举措,也是推动计算机类专业教学发展的有效途径。为解决计算机类相关专业课程的教学困境,帮助学生对编程类课程抽象理论内容的理解,提出思政背景下的C++程序设计课程混合式教学模式。实践证明,改进后的混合式教学模式深受学生喜爱,显著改善了教学效果,促进了专业师资队伍建设。 展开更多
关键词 面向对象程序设计 课程思政 线上线下 混合式教学模式
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Web测试综述 被引量:39
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作者 许蕾 徐宝文 陈振强 《计算机科学》 CSCD 北大核心 2003年第3期100-104,共5页
With the extensive application of Web technology,it becomes more and more critical of the request to thequality and reliability of Web applications. Then it is crucial to test Web applications automaticly,entirely and... With the extensive application of Web technology,it becomes more and more critical of the request to thequality and reliability of Web applications. Then it is crucial to test Web applications automaticly,entirely and thor-oughly. So we make a study of some Web testing methods and technologies. First,we discuss the necessity of Webtesting,then analyze where the faults may take place based on the architecture of the Web ,next discuss various meth-ods of Web testing in details. Then,based on the ideology of Object-Oriented,we build a model for Web testing,anddiscuss the method of doing some pertinence testing on pages when we utilize the information of statistic. At last,weintroduce some tools for white-box testing. 展开更多
关键词 WEB 测试 计算机网络 安全性 兼容性 浏览器 数据库
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