对某不锈钢结构点焊车体吊挂区域,通过有限元软件HypreMesh建模,基于BS EN 12663:2000标准的疲劳工况和网格不敏感结构应力法计算出模型的疲劳寿命,结果表明:结构焊点不能满足要求。设计采用加密焊点的方法,来满足点焊接头的疲劳寿命要...对某不锈钢结构点焊车体吊挂区域,通过有限元软件HypreMesh建模,基于BS EN 12663:2000标准的疲劳工况和网格不敏感结构应力法计算出模型的疲劳寿命,结果表明:结构焊点不能满足要求。设计采用加密焊点的方法,来满足点焊接头的疲劳寿命要求,并通过实测加速度反应谱及雨流技术的损伤评估,证明了吊挂区域疲劳性能达到设计要求。展开更多
In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channe...In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channel sensing and data transmission and focus on the optimal SST structure to maximize the SU's expected achievable throughput.We consider imperfect knowledge of energy harvesting rate,which cannot be exactly known and only its statistical information is available.By formulating the problem of expected achievable throughput optimization as a mixed-integer non-linear programming one,we derive the optimal saveratio and number of sensed channels with indepth analysis.Simulation results show that the optimal SST structure outperforms random one and performance gain can be enhanced by increasing the SU's energy harvesting rate.展开更多
文摘对某不锈钢结构点焊车体吊挂区域,通过有限元软件HypreMesh建模,基于BS EN 12663:2000标准的疲劳工况和网格不敏感结构应力法计算出模型的疲劳寿命,结果表明:结构焊点不能满足要求。设计采用加密焊点的方法,来满足点焊接头的疲劳寿命要求,并通过实测加速度反应谱及雨流技术的损伤评估,证明了吊挂区域疲劳性能达到设计要求。
基金supported by National Nature Science Foundation of China（NO.61372109）
文摘In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channel sensing and data transmission and focus on the optimal SST structure to maximize the SU's expected achievable throughput.We consider imperfect knowledge of energy harvesting rate,which cannot be exactly known and only its statistical information is available.By formulating the problem of expected achievable throughput optimization as a mixed-integer non-linear programming one,we derive the optimal saveratio and number of sensed channels with indepth analysis.Simulation results show that the optimal SST structure outperforms random one and performance gain can be enhanced by increasing the SU's energy harvesting rate.
