Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different conce...Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric coefficients.The combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical calculations.In this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different components.In contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric properties.Based on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are explored.We also find the components with the best piezoelectric property and comprehensive performance.Moreover,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs.展开更多
目的：探讨心率变异性分析对辣椒素疼痛模型进行评价的可行性。方法：22～27岁健康志愿者36名,取平静状态20 min ECG信号中较稳定的一段长度5 min信号作为对照;以浸透0.5 m L辣椒素溶液的棉纸片覆盖下唇唇红位置,继续记录20 min心电信号...目的：探讨心率变异性分析对辣椒素疼痛模型进行评价的可行性。方法：22～27岁健康志愿者36名,取平静状态20 min ECG信号中较稳定的一段长度5 min信号作为对照;以浸透0.5 m L辣椒素溶液的棉纸片覆盖下唇唇红位置,继续记录20 min心电信号,选取较稳定的一段长度5 min;记录涂抹辣椒素后的VAS评分;用Matlab R2006a编程软件分析所采集到的ECG信号,计算平静状态下（T0）和辣椒素刺激状态下（T1）的心率变异性（HRV）指标,进行统计学分析。结果：视觉模拟评分（VAS）平均（63.36±11.21）,可评价为中度疼痛;心率在T1时期较T0时期增加,无统计学意义。HRV时域分析指标NN间期标准差（SDNN）、相邻NN间期差的均方根（RMSSD）在T1期均较T0期明显升高;HRV频域分析指标总功率（TP）、低频功率（LF）、高频功率（HF）以及LF/HF在T1期均较T0期明显升高;散点图分析结果：散点图短轴（SD1）和散点图长轴（SD2）在T1时期较T0时期均明显升高。结论：用辣椒素建立疼痛模型是可行的,且操作简单,易于实施;HRV分析有可能在疼痛的量化评价中具有一定权衡作用。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.52272116 and 12002400)the Natural Science Foundation of Shandong Province (Grant No.ZR2021ME096)the Youth Innovation Team Project of Shandong Provincial Education Department (Grant No.2019KJJ012)。
文摘Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric coefficients.The combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical calculations.In this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different components.In contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric properties.Based on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are explored.We also find the components with the best piezoelectric property and comprehensive performance.Moreover,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs.
文摘目的：探讨心率变异性分析对辣椒素疼痛模型进行评价的可行性。方法：22～27岁健康志愿者36名,取平静状态20 min ECG信号中较稳定的一段长度5 min信号作为对照;以浸透0.5 m L辣椒素溶液的棉纸片覆盖下唇唇红位置,继续记录20 min心电信号,选取较稳定的一段长度5 min;记录涂抹辣椒素后的VAS评分;用Matlab R2006a编程软件分析所采集到的ECG信号,计算平静状态下（T0）和辣椒素刺激状态下（T1）的心率变异性（HRV）指标,进行统计学分析。结果：视觉模拟评分（VAS）平均（63.36±11.21）,可评价为中度疼痛;心率在T1时期较T0时期增加,无统计学意义。HRV时域分析指标NN间期标准差（SDNN）、相邻NN间期差的均方根（RMSSD）在T1期均较T0期明显升高;HRV频域分析指标总功率（TP）、低频功率（LF）、高频功率（HF）以及LF/HF在T1期均较T0期明显升高;散点图分析结果：散点图短轴（SD1）和散点图长轴（SD2）在T1时期较T0时期均明显升高。结论：用辣椒素建立疼痛模型是可行的,且操作简单,易于实施;HRV分析有可能在疼痛的量化评价中具有一定权衡作用。
