针对无线传感器网络在道路监控、管道传输等一维环境中的应用,提出了基于接收信号强度比值的一维定位算法1-DIM-RSSR(1Dimension Received Signal Strength Ratio)。该算法基于一维线性定位的思想,利用接收信号强度比值来确定未知节点...针对无线传感器网络在道路监控、管道传输等一维环境中的应用,提出了基于接收信号强度比值的一维定位算法1-DIM-RSSR(1Dimension Received Signal Strength Ratio)。该算法基于一维线性定位的思想,利用接收信号强度比值来确定未知节点的位置,只需要一次建立接收信号强度比值的数据库。实验结果表明,当环境改变时,与RSSI算法相比,1-DIM-RSSR算法定位精度高,在一维线性应用领域表现出了良好的灵活性和实用性。展开更多
目的运用3.0T磁共振T2加权像(T2WI)判断APPswe/PSEN1dE9(APP/PS1)双转基因小鼠在miRNA-146a干预下的神经影像变化。方法使用GE Signa Excite HD 3.0T超导磁共振扫描仪对中期(12月龄)的APP/PS1双转基因小鼠(AD组)、mRNA-146a干预治疗后AP...目的运用3.0T磁共振T2加权像(T2WI)判断APPswe/PSEN1dE9(APP/PS1)双转基因小鼠在miRNA-146a干预下的神经影像变化。方法使用GE Signa Excite HD 3.0T超导磁共振扫描仪对中期(12月龄)的APP/PS1双转基因小鼠(AD组)、mRNA-146a干预治疗后APP/PS1双转基因小鼠(干预组)、相同背景非转基因野生型小鼠C57小鼠(正常组),每组5只,以及对应的3组晚期(18月龄)小鼠,每组4只,行T2WI冠状位扫描。应用GE Medical Systems Functool 4.4工作站软件进行图像后处理,测得1 mm2感兴趣区(ROI)下的海马与同侧肌肉的T2WI信号强度比值。采用方差分析比较中晚期各组小鼠的T2WI信号强度。结果与正常组比较,AD组小鼠显示的海马区散在点状T2WI低信号影增多,干预组小鼠海马区T2WI信号较相同月龄AD组的小鼠强。12、18月龄AD组小鼠的T2WI信号强度比值均比正常组降低(P<0.05或0.01);干预组的T2WI信号强度比值则高于AD组(P<0.01),与正常组比较差异无统计学意义(P>0.05)。中晚期各组小鼠的肌肉信号相对稳定,差异无统计学意义(P>0.05)。结论运用3.0T磁共振T2WI成像对海马区的T2信号强度比值进行对比分析,有助于判断APP/PS1双转基因小鼠的成模情况及其在miRNA-146a干预治疗下的疗效。展开更多
In the technique of robot-assisted invasive surgery, high quality image is a key factor of the visual navigation system. In this paper, the authors have made a study of the image processing in visual system. Based on ...In the technique of robot-assisted invasive surgery, high quality image is a key factor of the visual navigation system. In this paper, the authors have made a study of the image processing in visual system. Based on the analysis of plentiful demising methods, they proposed a new method （S-AM-W） which oxnbines Adaptive Median filter and Wioaer filter to renmve the main noises （Salt ＆ Pepper noise and Gattssian noise）. The sinlflation results show that it is simple, well real time, and has high Peak Signal-to-Noise Ratio （PSNR）. It was found that the new method is effective and efficient in dealing with medical image of background noise.展开更多
An efficient adaptive approximation demosaicking algorithm based on the sampled edge pattern was presented for mosaic images from Bayer color filter array. The proposed algorithm determined edge patterns by four neare...An efficient adaptive approximation demosaicking algorithm based on the sampled edge pattern was presented for mosaic images from Bayer color filter array. The proposed algorithm determined edge patterns by four nearest green values surrounding the green interpolation location. Then according to the edge patterns, different adaptive interpolation steps were applied. Simulations on 12 Kodak photos and 15 IMAX high-quality images showed that the proposed method outperformed the other four demosaicking methods (bilinear, effective color interpolation, Lu's method and Chen's method) for average color peak signal to noise ratios and maintained a relatively low complexity owing to constant color-difference interpolation step and a reasonable terminating condition of iteration.展开更多
目的探讨不同b值对子宫内膜癌弥散加权成像信号强度的影响。方法采用不同b值条件(b值分别取50、400、800 s/mm2)对46例子宫内膜癌患者在3.0 T MRI上进行弥散加权成像,选择病变感兴趣区及正常子宫肌层部位分别进行信号强度的测定并计算...目的探讨不同b值对子宫内膜癌弥散加权成像信号强度的影响。方法采用不同b值条件(b值分别取50、400、800 s/mm2)对46例子宫内膜癌患者在3.0 T MRI上进行弥散加权成像,选择病变感兴趣区及正常子宫肌层部位分别进行信号强度的测定并计算信号强度比(SIR),进行统计学分析。结果所有子宫内膜癌病例于b=50 s/mm2弥散像均为稍高或明显高信号,且随着b值的增加时(400、800 s/mm2)病变与正常子宫肌层SIR值均较b=50 s/mm2时增大,差异具有统计学意义(P<0.05)。结论不同b值对子宫内膜癌弥散加权成像信号强度有影响,且随着b值的增加,病变与正常子宫肌层的SIR增大。展开更多
文摘针对无线传感器网络在道路监控、管道传输等一维环境中的应用,提出了基于接收信号强度比值的一维定位算法1-DIM-RSSR(1Dimension Received Signal Strength Ratio)。该算法基于一维线性定位的思想,利用接收信号强度比值来确定未知节点的位置,只需要一次建立接收信号强度比值的数据库。实验结果表明,当环境改变时,与RSSI算法相比,1-DIM-RSSR算法定位精度高,在一维线性应用领域表现出了良好的灵活性和实用性。
文摘目的运用3.0T磁共振T2加权像(T2WI)判断APPswe/PSEN1dE9(APP/PS1)双转基因小鼠在miRNA-146a干预下的神经影像变化。方法使用GE Signa Excite HD 3.0T超导磁共振扫描仪对中期(12月龄)的APP/PS1双转基因小鼠(AD组)、mRNA-146a干预治疗后APP/PS1双转基因小鼠(干预组)、相同背景非转基因野生型小鼠C57小鼠(正常组),每组5只,以及对应的3组晚期(18月龄)小鼠,每组4只,行T2WI冠状位扫描。应用GE Medical Systems Functool 4.4工作站软件进行图像后处理,测得1 mm2感兴趣区(ROI)下的海马与同侧肌肉的T2WI信号强度比值。采用方差分析比较中晚期各组小鼠的T2WI信号强度。结果与正常组比较,AD组小鼠显示的海马区散在点状T2WI低信号影增多,干预组小鼠海马区T2WI信号较相同月龄AD组的小鼠强。12、18月龄AD组小鼠的T2WI信号强度比值均比正常组降低(P<0.05或0.01);干预组的T2WI信号强度比值则高于AD组(P<0.01),与正常组比较差异无统计学意义(P>0.05)。中晚期各组小鼠的肌肉信号相对稳定,差异无统计学意义(P>0.05)。结论运用3.0T磁共振T2WI成像对海马区的T2信号强度比值进行对比分析,有助于判断APP/PS1双转基因小鼠的成模情况及其在miRNA-146a干预治疗下的疗效。
基金supported by the Henan Province Innovation and Technology Fund for Outstanding Scholarship(0421000500)the Key Scientific Research Projects of Henan University of Technology(09XZD008)the support of the Chinese National Programs for Hi-Tech R&D(2007AA704339)
文摘In the technique of robot-assisted invasive surgery, high quality image is a key factor of the visual navigation system. In this paper, the authors have made a study of the image processing in visual system. Based on the analysis of plentiful demising methods, they proposed a new method （S-AM-W） which oxnbines Adaptive Median filter and Wioaer filter to renmve the main noises （Salt ＆ Pepper noise and Gattssian noise）. The sinlflation results show that it is simple, well real time, and has high Peak Signal-to-Noise Ratio （PSNR）. It was found that the new method is effective and efficient in dealing with medical image of background noise.
基金Supported by National Natural Science Foundation of China(No.60975001 and No.61271412)
文摘An efficient adaptive approximation demosaicking algorithm based on the sampled edge pattern was presented for mosaic images from Bayer color filter array. The proposed algorithm determined edge patterns by four nearest green values surrounding the green interpolation location. Then according to the edge patterns, different adaptive interpolation steps were applied. Simulations on 12 Kodak photos and 15 IMAX high-quality images showed that the proposed method outperformed the other four demosaicking methods (bilinear, effective color interpolation, Lu's method and Chen's method) for average color peak signal to noise ratios and maintained a relatively low complexity owing to constant color-difference interpolation step and a reasonable terminating condition of iteration.
