为了提高导重法求解拓扑优化问题的计算效果,提出一种改进的导重法,并引入了灰度过滤技术抑制优化过程中灰度单元的产生.首先基于RAMP(the rational approximation of material properties)模型结合导重法求解最小柔度拓扑优化问题的迭...为了提高导重法求解拓扑优化问题的计算效果,提出一种改进的导重法,并引入了灰度过滤技术抑制优化过程中灰度单元的产生.首先基于RAMP(the rational approximation of material properties)模型结合导重法求解最小柔度拓扑优化问题的迭代表达式,利用二分法对表达式中的拉格朗日乘子求法进行了改进;为减少优化后结构图像中的灰度单元数量,在迭代表达式中引入灰度过滤函数;最后将上述理论拓展到多工况拓扑优化问题中,采用归一化组合处理方法建立目标函数.对多工况拓扑优化问题的2个典型算例进行计算的结果表明,应用文中理论求解拓扑优化问题具有收敛稳定、求解快速、图像清晰的特点.展开更多
Benue State of Nigeria is tagged the Food Basket of the country due to its heavy production of many classes of food. Situated in the North Central Geo-Political area of the country, its food production ranges from roo...Benue State of Nigeria is tagged the Food Basket of the country due to its heavy production of many classes of food. Situated in the North Central Geo-Political area of the country, its food production ranges from root crops, fruits to cereals. Recommender systems (RSs) allow users to access products of interest, given a plethora of interest on the Internet. Recommendation techniques are content-based and collaborative filtering. Recommender systems based on collaborative filtering outshines content-based systems in the quality of their recommendations, but suffers from the cold start problem, i.e., not being able to recommend items that have few or no ratings. On the other hand, content-based recommender systems are able to recommend both old and new items but with low recommendation quality in relation to the user’s preference. This work combines collaborative filtering and content based recommendation into one system and presents experimental results obtained from a web and mobile application used in the simulation. The work solves the problem of serendipity associated with content based (RS) as well as the problem of ramp-up associated with collaborative filtering. The results indicate that the quality of recommendation is promising and is competitive with collaborative technique recommending items that have been seen before and also effective at recommending cold-start products.展开更多
文摘为了提高导重法求解拓扑优化问题的计算效果,提出一种改进的导重法,并引入了灰度过滤技术抑制优化过程中灰度单元的产生.首先基于RAMP(the rational approximation of material properties)模型结合导重法求解最小柔度拓扑优化问题的迭代表达式,利用二分法对表达式中的拉格朗日乘子求法进行了改进;为减少优化后结构图像中的灰度单元数量,在迭代表达式中引入灰度过滤函数;最后将上述理论拓展到多工况拓扑优化问题中,采用归一化组合处理方法建立目标函数.对多工况拓扑优化问题的2个典型算例进行计算的结果表明,应用文中理论求解拓扑优化问题具有收敛稳定、求解快速、图像清晰的特点.
文摘Benue State of Nigeria is tagged the Food Basket of the country due to its heavy production of many classes of food. Situated in the North Central Geo-Political area of the country, its food production ranges from root crops, fruits to cereals. Recommender systems (RSs) allow users to access products of interest, given a plethora of interest on the Internet. Recommendation techniques are content-based and collaborative filtering. Recommender systems based on collaborative filtering outshines content-based systems in the quality of their recommendations, but suffers from the cold start problem, i.e., not being able to recommend items that have few or no ratings. On the other hand, content-based recommender systems are able to recommend both old and new items but with low recommendation quality in relation to the user’s preference. This work combines collaborative filtering and content based recommendation into one system and presents experimental results obtained from a web and mobile application used in the simulation. The work solves the problem of serendipity associated with content based (RS) as well as the problem of ramp-up associated with collaborative filtering. The results indicate that the quality of recommendation is promising and is competitive with collaborative technique recommending items that have been seen before and also effective at recommending cold-start products.