Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study ...Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study the friction and wear behavior of parts made of newly developed Nylon6-Fe composite material by FDM. This work also involves the comparison of the friction and wear characteristics of the Nylon6-Fe composite with the existing acrylonitrile butadiene styrene(ABS) filament of the FDM machine. This Is carried out on the pin on disk setup by varying the load(5, 10, 15 and 20 N) and speed(200 and 300 r/min). It is concluded that the newly developed composite is highly wear resistant and can be used in industrial applications where wear resistance is of paramount importance. Morphology of the surface in contact with the Nylon6-Fe composite and ABS is also carried out.展开更多
文摘为提高大西洋热带海域长鳍金枪鱼(Thunnus alalunga)渔场预报的准确率,对K最近邻(k nearest neighbor,KNN)、逻辑斯蒂回归(logistic regression,LR)、决策与分类树(classfication and regression tree,CART)、梯度提升决策树(gradient boosting decision tree,GBDT)、随机森林(random forest,RF)、支持向量机(support vector machine,SVM)和Stacking集成(stacking ensemble learning,STK)共7个模型的预报性能进行了对比分析。该7个模型利用2016~2019年在大西洋公海海域(19°16′S~16°21′N;46°27′W~2°09′E)作业的13艘中国远洋延绳钓渔船的渔业数据,结合0~500 m不同水层的温度、盐度、溶解氧、叶绿素a浓度、海表面风速、涡动能和混合层深度数据建立。各模型取75%数据作为训练数据,25%为测试数据,采用预报准确率(accuracy,ACC)与接受者操作特征曲线下面积(area under curve,AUC)评价建立的单位努力量渔获量(catch per unit of effort,CPUE)与海洋环境因子关系模型的性能。结果表明:(1)STK模型对大西洋长鳍金枪鱼渔场的预报性能相比其他模型明显提高,ACC为75.92%,AUC为0.742;(2)基于STK模型预测得到的中心渔场范围总体上与实际作业渔场一致;(3)影响大西洋长鳍金枪鱼渔场分布的海洋环境因子主要为100 m水层的温度、盐度,以及100、150、500 m水层的溶解氧。研究表明STK模型对大西洋长鳍金枪鱼渔场的预报准确率较高,性能良好。
基金PTU Jalandhar,Manufacturing Research Lab GNDEC,Ludhiana and DST GOI for financial support
文摘Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study the friction and wear behavior of parts made of newly developed Nylon6-Fe composite material by FDM. This work also involves the comparison of the friction and wear characteristics of the Nylon6-Fe composite with the existing acrylonitrile butadiene styrene(ABS) filament of the FDM machine. This Is carried out on the pin on disk setup by varying the load(5, 10, 15 and 20 N) and speed(200 and 300 r/min). It is concluded that the newly developed composite is highly wear resistant and can be used in industrial applications where wear resistance is of paramount importance. Morphology of the surface in contact with the Nylon6-Fe composite and ABS is also carried out.
