This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are c...This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope.展开更多
This paper presents a robust algorithm to generate support for fused deposition modeling (FDM). Since many flaws appear in most stereo lithography (STL) models, this algorithm utilizes slice data as input. A top-down ...This paper presents a robust algorithm to generate support for fused deposition modeling (FDM). Since many flaws appear in most stereo lithography (STL) models, this algorithm utilizes slice data as input. A top-down approach was used to calculate the support slice layer by layer. The generation algorithm was described in detail including the slice grouping, oriental bounding box (OBB) calculation, offsetting, and Boolean operations. Several cases are given to validate the efficiency and robustness of the procedure. The algorithm provides necessary support not only for hanging surface but also for hanging vertexes and edges with O(n) time complexity, where n is the number of layers. The algorithm fully utilizes the parts’ self-support ability and reduces support volume to the maximum extent. This slice data based algorithm has the same efficiency as the STL based algorithm but is more stable, which significantly enhances the robustness of the support generation process.展开更多
为了满足智能电网对高实时性、高可靠性与大带宽通信系统的迫切需求,以某智能变电站示范工程项目为背景,设计并实现一套面向智能应用的电力通信数据传输系统。通过构建分层式网络架构,融合电力载波通信(Power Line Communication,PLC)...为了满足智能电网对高实时性、高可靠性与大带宽通信系统的迫切需求,以某智能变电站示范工程项目为背景,设计并实现一套面向智能应用的电力通信数据传输系统。通过构建分层式网络架构,融合电力载波通信(Power Line Communication,PLC)与工业以太网技术,引入边缘计算与网络切片机制,提升系统在复杂电磁环境下的多业务承载能力与服务质量。实验结果表明,该系统有效解决了传统电力通信网络在带宽、时延与安全性方面存在的问题,具备良好的工程应用价值。展开更多
为提升船舶波浪增阻计算的准确度,基于实船航行数据,分别采用数值计算方法和经验公式计算船舶的波浪增阻。以一艘散货船为例,收集其船型信息,根据船型信息计算得到波浪增阻响应曲线;收集该船的航行监测数据,通过Python编程计算各采样数...为提升船舶波浪增阻计算的准确度,基于实船航行数据,分别采用数值计算方法和经验公式计算船舶的波浪增阻。以一艘散货船为例,收集其船型信息,根据船型信息计算得到波浪增阻响应曲线;收集该船的航行监测数据,通过Python编程计算各采样数据对应的波浪增阻响应曲线,通过国际拖曳水池会议(International Towing Tank Conference,ITTC)双参数海浪谱匹配各采样数据下的波高和波浪周期,求解出对应的波浪增阻;基于ISO15016:2015规程修正风、浪、温度和水密度等参数,通过对轴功率进行波浪增阻、水温和风阻等方面的修正得到理想的静水功率。将修正结果与散货船快速性模型试验结果相对比,验证采用SNNM(SHOPERA-NTUA-NTUMARIC)方法所得船舶波浪增阻相比采用切片法所得波浪增阻更准确,与实船波浪增阻更接近。展开更多
基金The National Natural Science Foundation of China(No.60425206,60633010)the High Technology Research and Development Program of Jiangsu Province(No.BG2005032)
文摘This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope.
基金Supported by the Natural Science Fund Project of Hubei Province of China (2004ABC001)
文摘This paper presents a robust algorithm to generate support for fused deposition modeling (FDM). Since many flaws appear in most stereo lithography (STL) models, this algorithm utilizes slice data as input. A top-down approach was used to calculate the support slice layer by layer. The generation algorithm was described in detail including the slice grouping, oriental bounding box (OBB) calculation, offsetting, and Boolean operations. Several cases are given to validate the efficiency and robustness of the procedure. The algorithm provides necessary support not only for hanging surface but also for hanging vertexes and edges with O(n) time complexity, where n is the number of layers. The algorithm fully utilizes the parts’ self-support ability and reduces support volume to the maximum extent. This slice data based algorithm has the same efficiency as the STL based algorithm but is more stable, which significantly enhances the robustness of the support generation process.
文摘为了满足智能电网对高实时性、高可靠性与大带宽通信系统的迫切需求,以某智能变电站示范工程项目为背景,设计并实现一套面向智能应用的电力通信数据传输系统。通过构建分层式网络架构,融合电力载波通信(Power Line Communication,PLC)与工业以太网技术,引入边缘计算与网络切片机制,提升系统在复杂电磁环境下的多业务承载能力与服务质量。实验结果表明,该系统有效解决了传统电力通信网络在带宽、时延与安全性方面存在的问题,具备良好的工程应用价值。
文摘为提升船舶波浪增阻计算的准确度,基于实船航行数据,分别采用数值计算方法和经验公式计算船舶的波浪增阻。以一艘散货船为例,收集其船型信息,根据船型信息计算得到波浪增阻响应曲线;收集该船的航行监测数据,通过Python编程计算各采样数据对应的波浪增阻响应曲线,通过国际拖曳水池会议(International Towing Tank Conference,ITTC)双参数海浪谱匹配各采样数据下的波高和波浪周期,求解出对应的波浪增阻;基于ISO15016:2015规程修正风、浪、温度和水密度等参数,通过对轴功率进行波浪增阻、水温和风阻等方面的修正得到理想的静水功率。将修正结果与散货船快速性模型试验结果相对比,验证采用SNNM(SHOPERA-NTUA-NTUMARIC)方法所得船舶波浪增阻相比采用切片法所得波浪增阻更准确,与实船波浪增阻更接近。
