电池充电时的初始荷电状态SOC(state of charge)往往是随机的,因此在实际应用中难以得到锂电池完整的充电数据,针对这一问题提出一种基于部分充电数据的锂电池健康状态SOH(state of health)估计方法。通过建立的门控循环单元-反向传播GR...电池充电时的初始荷电状态SOC(state of charge)往往是随机的,因此在实际应用中难以得到锂电池完整的充电数据,针对这一问题提出一种基于部分充电数据的锂电池健康状态SOH(state of health)估计方法。通过建立的门控循环单元-反向传播GRU-BP(gated recurrent unit-back propagation)模型,可以由部分充电数据得到完整的充电曲线,然后在完整的充电曲线中提取能够有效表征电池老化程度的特征进行SOH预测。该方法能够实现在恒流充电模式下的任意定长电压区间充电数据下电池的SOH估计。通过实验证明,所提出的模型在数据不完备的情况下能够有效预测锂电池SOH,其估计的均方根误差RMSE(root mean square error)均在2%以下。展开更多
文章研究并实践了一种把夺旗赛(Capture the Flag,CTF)和神经网络结合起来的网络安全防御办法。研究的重点创新在于方法迁移,也就是把在交通流量预测方面已验证有效的时序预测模型,用于网络安全领域,以此实现对网络攻击流量的动态感知...文章研究并实践了一种把夺旗赛(Capture the Flag,CTF)和神经网络结合起来的网络安全防御办法。研究的重点创新在于方法迁移,也就是把在交通流量预测方面已验证有效的时序预测模型,用于网络安全领域,以此实现对网络攻击流量的动态感知和短期预测。文章设计了一个基于门控循环单元(Gated Recurrent Unit,GRU)的网络攻击流量预测模型。这个模型能根据过去的网络流量数据来预测未来的网络流量情况,起到短期预警的作用。另外,文章构建了“数据驱动、智能预警”的CTF融合模式。在攻防实践的时候,不再只是依靠已有的知识来防御,还能根据GRU网络流量模型提供的预测信息,提前调整应对策略,实现从“被动挨打式应对”到“主动提前布防”的转变。展开更多
An accurate prediction of earth pressure balance(EPB)shield moving performance is important to ensure the safety tunnel excavation.A hybrid model is developed based on the particle swarm optimization(PSO)and gated rec...An accurate prediction of earth pressure balance(EPB)shield moving performance is important to ensure the safety tunnel excavation.A hybrid model is developed based on the particle swarm optimization(PSO)and gated recurrent unit(GRU)neural network.PSO is utilized to assign the optimal hyperparameters of GRU neural network.There are mainly four steps:data collection and processing,hybrid model establishment,model performance evaluation and correlation analysis.The developed model provides an alternative to tackle with time-series data of tunnel project.Apart from that,a novel framework about model application is performed to provide guidelines in practice.A tunnel project is utilized to evaluate the performance of proposed hybrid model.Results indicate that geological and construction variables are significant to the model performance.Correlation analysis shows that construction variables(main thrust and foam liquid volume)display the highest correlation with the cutterhead torque(CHT).This work provides a feasible and applicable alternative way to estimate the performance of shield tunneling.展开更多
摘要电池充电时的初始荷电状态SOC(state of charge)往往是随机的,因此在实际应用中难以得到锂电池完整的充电数据,针对这一问题提出一种基于部分充电数据的锂电池健康状态SOH(state of health)估计方法。通过建立的门控循环单元-反向传播GRU-BP(gated recurrent unit-back propagation)模型,可以由部分充电数据得到完整的充电曲线,然后在完整的充电曲线中提取能够有效表征电池老化程度的特征进行SOH预测。该方法能够实现在恒流充电模式下的任意定长电压区间充电数据下电池的SOH估计。通过实验证明,所提出的模型在数据不完备的情况下能够有效预测锂电池SOH,其估计的均方根误差RMSE(root mean square error)均在2%以下。
摘要文章研究并实践了一种把夺旗赛(Capture the Flag,CTF)和神经网络结合起来的网络安全防御办法。研究的重点创新在于方法迁移,也就是把在交通流量预测方面已验证有效的时序预测模型,用于网络安全领域,以此实现对网络攻击流量的动态感知和短期预测。文章设计了一个基于门控循环单元(Gated Recurrent Unit,GRU)的网络攻击流量预测模型。这个模型能根据过去的网络流量数据来预测未来的网络流量情况,起到短期预警的作用。另外,文章构建了“数据驱动、智能预警”的CTF融合模式。在攻防实践的时候,不再只是依靠已有的知识来防御,还能根据GRU网络流量模型提供的预测信息,提前调整应对策略,实现从“被动挨打式应对”到“主动提前布防”的转变。
基金funded by“The Pearl River Talent Recruitment Program”of Guangdong Province in 2019(Grant No.2019CX01G338)the Research Funding of Shantou University for New Faculty Member(Grant No.NTF19024-2019).
摘要An accurate prediction of earth pressure balance(EPB)shield moving performance is important to ensure the safety tunnel excavation.A hybrid model is developed based on the particle swarm optimization(PSO)and gated recurrent unit(GRU)neural network.PSO is utilized to assign the optimal hyperparameters of GRU neural network.There are mainly four steps:data collection and processing,hybrid model establishment,model performance evaluation and correlation analysis.The developed model provides an alternative to tackle with time-series data of tunnel project.Apart from that,a novel framework about model application is performed to provide guidelines in practice.A tunnel project is utilized to evaluate the performance of proposed hybrid model.Results indicate that geological and construction variables are significant to the model performance.Correlation analysis shows that construction variables(main thrust and foam liquid volume)display the highest correlation with the cutterhead torque(CHT).This work provides a feasible and applicable alternative way to estimate the performance of shield tunneling.