We present the electromagnetically induced transparency(EIT)spectra of cold Rydberg four-level cascade atoms consisting of the 6S_(1/2)→6P_(3/2)→7S_(1/2)→60P_(3/2) scheme.A coupling laser drives the Rydberg transit...We present the electromagnetically induced transparency(EIT)spectra of cold Rydberg four-level cascade atoms consisting of the 6S_(1/2)→6P_(3/2)→7S_(1/2)→60P_(3/2) scheme.A coupling laser drives the Rydberg transition,a dressing laser couples two intermediate levels and a weak probe laser probes the EIT signal.We numerically solve the Bloch equations and investigate the dependence of the probe transmission rate signal on the coupling and dressing lasers.We find that the probe transmission rate can display an EIT or electromagnetically induced absorption(EIA)profile,depending on the Rabi frequencies of the coupling and dressing lasers.When we increase the Rabi frequency of the coupling laser and keep the Rabi frequency of the probe and dressing laser fixed,flipping of the EIA to EIT spectrum occurs at the critical coupling Rabi frequency.When we apply a microwave field coupling the transition 60P_(3/2)→61S_(1/2),the EIT spectrum shows Autler–Townes splitting,which is employed to measure the microwave field.The theoretical measurement sensitivity can be 1.52×10^(−2) nV・cm^(−1)・Hz−^(1/2) at the EIA–EIT flipping point.展开更多
全球气候变暖已经成为人类迫切需要解决的难题,精确预测全球气温变化趋势对于把握气候发展状态、维护生态环境具有重要的意义。文章提出一种基于变分模态分解(VMD)与长短记忆神经网络(LSTM)的气温预测模型(VMD-LSTM),实现了对全球月平...全球气候变暖已经成为人类迫切需要解决的难题,精确预测全球气温变化趋势对于把握气候发展状态、维护生态环境具有重要的意义。文章提出一种基于变分模态分解(VMD)与长短记忆神经网络(LSTM)的气温预测模型(VMD-LSTM),实现了对全球月平均气温的准确预测。首先,对全球月平均气温进行VMD分解,得到了7个分量。其次,构造了LSTM一步预测模型对每一个VMD分量进行了预测。最后,根据VMD分量的预测值得到了全球平均气温的预测结果。数值实验中讨论了LSTM、VMD-LSTM、GRU与VMD-GRU四种预测模型,其中文章提出的VMD-LSTM的预测效果最好,其R2值为0.872,MAPE为0.664%,RMSE为0.121。实验结果表明,文章提出的VMD-LSTM预测模型能够有效预测气温。Global warming has become an urgent problem for mankind. Accurate prediction of global temperature is of great significance for grasping the state of climate development and maintaining the ecological environment. In this paper, a temperature prediction model (VMD-LSTM) is proposed based on the variational modal decomposition (VMD) and the long-short memory neural network (LSTM). This model was used to make accurate predictions of global average monthly temperatures. Firstly, the global average monthly temperature is decomposed into seven components by VMD. Second, The VMD component is predicted by the LSTM one-step prediction model. Finally, the prediction of global average temperature was obtained based on the forecasted values of the VMD components. The numerical experiment discussed four forecasting models: LSTM, VMD-LSTM, GRU, and VMD-GRU, among which the VMD-LSTM model proposed in the paper showed the best prediction performance, with an R2 value of 0.872, MAPE of 0.664%, and RMSE of 0.121. The experimental results indicate that the VMD-LSTM prediction model proposed in the paper can effectively predict temperature.展开更多
进展期乳腺癌(advanced breast cancer,ABC)的治疗主要以系统治疗(包括化疗、内分泌治疗和分子靶向治疗)为主。原发灶的局部治疗(手术或放疗等)对于ABC患者生存的影响尚有争议。然而,近年来关于ABC局部治疗的研究越来越多,从已有结果和...进展期乳腺癌(advanced breast cancer,ABC)的治疗主要以系统治疗(包括化疗、内分泌治疗和分子靶向治疗)为主。原发灶的局部治疗(手术或放疗等)对于ABC患者生存的影响尚有争议。然而,近年来关于ABC局部治疗的研究越来越多,从已有结果和正在进行的试验结果来看,对ABC患者进行合适的局部治疗确实可使其生存获益或有获益趋势。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U2341211,62175136,12241408,and 12120101004)the Innovation Program for Quantum Science and Technology(Grant No.2023ZD0300902)+1 种基金the Fundamental Research Program of Shanxi Province(Grant No.202303021224007)the 1331 Project of Shanxi Province.
文摘We present the electromagnetically induced transparency(EIT)spectra of cold Rydberg four-level cascade atoms consisting of the 6S_(1/2)→6P_(3/2)→7S_(1/2)→60P_(3/2) scheme.A coupling laser drives the Rydberg transition,a dressing laser couples two intermediate levels and a weak probe laser probes the EIT signal.We numerically solve the Bloch equations and investigate the dependence of the probe transmission rate signal on the coupling and dressing lasers.We find that the probe transmission rate can display an EIT or electromagnetically induced absorption(EIA)profile,depending on the Rabi frequencies of the coupling and dressing lasers.When we increase the Rabi frequency of the coupling laser and keep the Rabi frequency of the probe and dressing laser fixed,flipping of the EIA to EIT spectrum occurs at the critical coupling Rabi frequency.When we apply a microwave field coupling the transition 60P_(3/2)→61S_(1/2),the EIT spectrum shows Autler–Townes splitting,which is employed to measure the microwave field.The theoretical measurement sensitivity can be 1.52×10^(−2) nV・cm^(−1)・Hz−^(1/2) at the EIA–EIT flipping point.
文摘全球气候变暖已经成为人类迫切需要解决的难题,精确预测全球气温变化趋势对于把握气候发展状态、维护生态环境具有重要的意义。文章提出一种基于变分模态分解(VMD)与长短记忆神经网络(LSTM)的气温预测模型(VMD-LSTM),实现了对全球月平均气温的准确预测。首先,对全球月平均气温进行VMD分解,得到了7个分量。其次,构造了LSTM一步预测模型对每一个VMD分量进行了预测。最后,根据VMD分量的预测值得到了全球平均气温的预测结果。数值实验中讨论了LSTM、VMD-LSTM、GRU与VMD-GRU四种预测模型,其中文章提出的VMD-LSTM的预测效果最好,其R2值为0.872,MAPE为0.664%,RMSE为0.121。实验结果表明,文章提出的VMD-LSTM预测模型能够有效预测气温。Global warming has become an urgent problem for mankind. Accurate prediction of global temperature is of great significance for grasping the state of climate development and maintaining the ecological environment. In this paper, a temperature prediction model (VMD-LSTM) is proposed based on the variational modal decomposition (VMD) and the long-short memory neural network (LSTM). This model was used to make accurate predictions of global average monthly temperatures. Firstly, the global average monthly temperature is decomposed into seven components by VMD. Second, The VMD component is predicted by the LSTM one-step prediction model. Finally, the prediction of global average temperature was obtained based on the forecasted values of the VMD components. The numerical experiment discussed four forecasting models: LSTM, VMD-LSTM, GRU, and VMD-GRU, among which the VMD-LSTM model proposed in the paper showed the best prediction performance, with an R2 value of 0.872, MAPE of 0.664%, and RMSE of 0.121. The experimental results indicate that the VMD-LSTM prediction model proposed in the paper can effectively predict temperature.
文摘进展期乳腺癌(advanced breast cancer,ABC)的治疗主要以系统治疗(包括化疗、内分泌治疗和分子靶向治疗)为主。原发灶的局部治疗(手术或放疗等)对于ABC患者生存的影响尚有争议。然而,近年来关于ABC局部治疗的研究越来越多,从已有结果和正在进行的试验结果来看,对ABC患者进行合适的局部治疗确实可使其生存获益或有获益趋势。
