Recently,the physics-informed neural network shows remarkable ability in the context of solving the low-dimensional nonlinear partial differential equations.However,for some cases of high-dimensional systems,such tech...Recently,the physics-informed neural network shows remarkable ability in the context of solving the low-dimensional nonlinear partial differential equations.However,for some cases of high-dimensional systems,such technique may be time-consuming and inaccurate.In this paper,the authors put forward a pre-training physics-informed neural network with mixed sampling(pPINN)to address these issues.Just based on the initial and boundary conditions,the authors design the pre-training stage to filter out the set of the misfitting points,which is regarded as part of the training points in the next stage.The authors further take the parameters of the neural network in Stage 1 as the initialization in Stage 2.The advantage of the proposed approach is that it takes less time to transfer the valuable information from the first stage to the second one to improve the calculation accuracy,especially for the high-dimensional systems.To verify the performance of the pPINN algorithm,the authors first focus on the growing-and-decaying mode of line rogue wave in the Davey-Stewartson I equation.Another case is the accelerated motion of lump in the inhomogeneous Kadomtsev-Petviashvili equation,which admits a more complex evolution than the uniform equation.The exact solution provides a perfect sample for data experiments,and can also be used as a reference frame to identify the performance of the algorithm.The experiments confirm that the pPINN algorithm can improve the prediction accuracy and training efficiency well,and reduce the training time to a large extent for simulating nonlinear waves of high-dimensional equations.展开更多
目的 探究腹腔镜辅助右半结肠癌D3根治术的临床疗效。方法 回顾性分析2013年1月至2018年10月60例右半结肠癌患者资料,均行右半结肠癌D3根治术。2013年1月至2015年6月30例患者为开腹组;2015年7月至2018年10月30例患者为腹腔镜组。采用统...目的 探究腹腔镜辅助右半结肠癌D3根治术的临床疗效。方法 回顾性分析2013年1月至2018年10月60例右半结肠癌患者资料,均行右半结肠癌D3根治术。2013年1月至2015年6月30例患者为开腹组;2015年7月至2018年10月30例患者为腹腔镜组。采用统计学软件SPSS 20.0 进行数据分析,围术期指标、炎性反应及免疫功能指标采用(±s)表示,独立t检验;并发症等计数资料采用χ 2 检验;P <0.05 差异有统计学意义。结果 腹腔镜组在手术时间方面长于开腹组,在术中出血量、术后排气排便时间、肠鸣音恢复时间、下床时间及住院时间等方面均优于开腹组( P <0.05)。两组患者术前WBC、CRP及血清胃泌素(GS)水平差异无统计学意义( P >0.05),术后均明显增加,但腹腔镜组低于开腹组( P <0.05)。两组患者术前CD4、CD8、CD4/CD8比较无统计学意义( P >0.05);术后均有所改善,但腹腔镜组患者的CD4、CD4/CD8较开腹组明显增高,CD8较开腹组明显降低( P <0.05)。两组患者术后并发症比较无统计学意义( P >0.05)。结论 腹腔镜辅助右半结肠癌D3根治术术中创伤小、出血少,术后恢复快,安全可行。展开更多
文摘Recently,the physics-informed neural network shows remarkable ability in the context of solving the low-dimensional nonlinear partial differential equations.However,for some cases of high-dimensional systems,such technique may be time-consuming and inaccurate.In this paper,the authors put forward a pre-training physics-informed neural network with mixed sampling(pPINN)to address these issues.Just based on the initial and boundary conditions,the authors design the pre-training stage to filter out the set of the misfitting points,which is regarded as part of the training points in the next stage.The authors further take the parameters of the neural network in Stage 1 as the initialization in Stage 2.The advantage of the proposed approach is that it takes less time to transfer the valuable information from the first stage to the second one to improve the calculation accuracy,especially for the high-dimensional systems.To verify the performance of the pPINN algorithm,the authors first focus on the growing-and-decaying mode of line rogue wave in the Davey-Stewartson I equation.Another case is the accelerated motion of lump in the inhomogeneous Kadomtsev-Petviashvili equation,which admits a more complex evolution than the uniform equation.The exact solution provides a perfect sample for data experiments,and can also be used as a reference frame to identify the performance of the algorithm.The experiments confirm that the pPINN algorithm can improve the prediction accuracy and training efficiency well,and reduce the training time to a large extent for simulating nonlinear waves of high-dimensional equations.
文摘目的 探究腹腔镜辅助右半结肠癌D3根治术的临床疗效。方法 回顾性分析2013年1月至2018年10月60例右半结肠癌患者资料,均行右半结肠癌D3根治术。2013年1月至2015年6月30例患者为开腹组;2015年7月至2018年10月30例患者为腹腔镜组。采用统计学软件SPSS 20.0 进行数据分析,围术期指标、炎性反应及免疫功能指标采用(±s)表示,独立t检验;并发症等计数资料采用χ 2 检验;P <0.05 差异有统计学意义。结果 腹腔镜组在手术时间方面长于开腹组,在术中出血量、术后排气排便时间、肠鸣音恢复时间、下床时间及住院时间等方面均优于开腹组( P <0.05)。两组患者术前WBC、CRP及血清胃泌素(GS)水平差异无统计学意义( P >0.05),术后均明显增加,但腹腔镜组低于开腹组( P <0.05)。两组患者术前CD4、CD8、CD4/CD8比较无统计学意义( P >0.05);术后均有所改善,但腹腔镜组患者的CD4、CD4/CD8较开腹组明显增高,CD8较开腹组明显降低( P <0.05)。两组患者术后并发症比较无统计学意义( P >0.05)。结论 腹腔镜辅助右半结肠癌D3根治术术中创伤小、出血少,术后恢复快,安全可行。
