目的回顾性评价急诊腹部CT影像经有损性三维(3D)静止图像压缩标准2000(Joint Photographic Experts Group 2000,JPEG2000)压缩后对诊断可信度与准确性的影响。方法研究经学院医学伦理委员会批准。将急腹症病人的104次连续多层cT检...目的回顾性评价急诊腹部CT影像经有损性三维(3D)静止图像压缩标准2000(Joint Photographic Experts Group 2000,JPEG2000)压缩后对诊断可信度与准确性的影响。方法研究经学院医学伦理委员会批准。将急腹症病人的104次连续多层cT检查的影像(层厚3mm;重建间隔2mm)传送至有损3DJPEG2000进行压缩,以384kB(12比特)作为原始影像大小,参照压缩比分别为10:1,12.5:1,与15:1。由3位放射医生相互独立地阅读原始影像与压缩影像.展开更多
A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminat...A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.展开更多
文摘目的回顾性评价急诊腹部CT影像经有损性三维(3D)静止图像压缩标准2000(Joint Photographic Experts Group 2000,JPEG2000)压缩后对诊断可信度与准确性的影响。方法研究经学院医学伦理委员会批准。将急腹症病人的104次连续多层cT检查的影像(层厚3mm;重建间隔2mm)传送至有损3DJPEG2000进行压缩,以384kB(12比特)作为原始影像大小,参照压缩比分别为10:1,12.5:1,与15:1。由3位放射医生相互独立地阅读原始影像与压缩影像.
文摘A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.