The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-n...The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs.展开更多
Waveguide-integrated optical modulators are indispensable for on-chip optical interconnects and optical computing.To cope with the ever-increasing amount of data being generated and consumed,ultrafast waveguide-integr...Waveguide-integrated optical modulators are indispensable for on-chip optical interconnects and optical computing.To cope with the ever-increasing amount of data being generated and consumed,ultrafast waveguide-integrated optical modulators with low energy consumption are highly demanded.In recent years,two-dimensional(2D)materials have attracted a lot of attention and have provided tremendous opportunities for the development of high-performance waveguide-integrated optical modulators because of their extraordinary optoelectronic properties and versatile compatibility.This paper reviews the state-of-the-art waveguide-integrated optical modulators with 2D materials,providing researchers with the developing trends in the field and allowing them to identify existing challenges and promising potential solutions.First,the concept and fundamental mechanisms of optical modulation with 2D materials are summarized.Second,a review of waveguide-integrated optical modulators employing electro-optic,all-optic,and thermo-optic effects is provided.Finally,the challenges and perspectives of waveguide-integrated modulators with 2D materials are discussed.展开更多
目的分析2型糖尿病患者25-羟维生素D[25(OH)D]水平,初步了解血清25(OH)D水平与2型糖尿病患者糖化血红蛋白(HbA1c)、胰岛功能等代谢指标的相关性。方法选择新乡市第一人民医院内分泌科2020年1月至2020年12月收治的459例2型糖尿病患者为...目的分析2型糖尿病患者25-羟维生素D[25(OH)D]水平,初步了解血清25(OH)D水平与2型糖尿病患者糖化血红蛋白(HbA1c)、胰岛功能等代谢指标的相关性。方法选择新乡市第一人民医院内分泌科2020年1月至2020年12月收治的459例2型糖尿病患者为研究对象。收集患者的临床资料,包括性别、年龄、血清25(OH)D、空腹胰岛素、C肽、HbA1c、空腹血糖、餐后血糖、尿微量白蛋白、尿白蛋白肌酐比值、血钙、血尿酸(UA)、三酰甘油(TG)、总胆固醇(TCH)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)等。根据血清25(OH)D水平将患者分为充足组[n=20,25(OH)D≥30μg·L^(-1)]、不足组[n=95,20μg·L^(-1)≤25(OH)D<30μg·L^(-1)]、缺乏组[n=231,10μg·L^(-1)≤25(OH)D<20μg·L^(-1)]、严重缺乏组[n=113,25(OH)D<10μg·L^(-1)]。比较4组患者各代谢指标的差异,采用Pearson相关分析25(OH)D与各代谢指标的相关性。结果2型糖尿病患者血清25(OH)D水平为3.00~46.59(15.75±0.35)μg·L^(-1),男性患者的血清25(OH)D水平显著高于女性患者(P<0.05)。2型糖尿病患者25(OH)D缺乏的患病率为74.9%(344/459),25(OH)D缺乏主要发生在1、2、3、4、11、12月份。不足组、缺乏组和严重缺乏组患者HbA1c显著高于充足组(P<0.05),缺乏组和严重缺乏组患者HbA1c显著高于不足组(P<0.05);缺乏组和严重缺乏组患者HbA1c比较差异无统计学意义(P>0.05)。充足组与不足组、缺乏组与严重缺乏组患者空腹血糖比较差异无统计学意义(P>0.05);缺乏组和严重缺乏组患者空腹血糖显著高于充足组、不足组(P<0.05)。充足组、不足组、缺乏组患者空腹胰岛素、尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值比较差异无统计学意义(P>0.05);严重缺乏组患者空腹胰岛素显著低于充足组、不足组和缺乏组,尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值显著高于充足组、不足组和缺乏组(P<0.05)。4组患者的稳态模型评估的胰岛素抵抗指数(HOMA-IR)、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙比较差异均无统计学意义(P>0.05)。Pearson相关性分析结果显示,2型糖尿病患者血清25(OH)D水平与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关(r=-0.093、-0.166、-0.157,P<0.05),与空腹胰岛素呈正相关(r=0.089,P<0.05)。2型糖尿病患者血清25(OH)D水平与空腹血糖、HOMA-IR、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙等无相关性(P>0.05)。结论2型糖尿病患者25(OH)D缺乏与不足普遍存在,女性患者缺乏更明显。2型糖尿病患者25(OH)D水平与空腹胰岛素呈正相关,与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关,25(OH)D缺乏的2型糖尿病患者主要分布在1、2、3、4、11、12月份。展开更多
临床医生可通过观察眼底视网膜血管及其分支对人体是否患有疾病进行早期诊断,但由于视网膜中的血管错综复杂,模型在分割时会出现对微细血管分割精确度不足的问题。为此,提出一种结合残差模块Res2-net以及高效通道注意力机制(efficient c...临床医生可通过观察眼底视网膜血管及其分支对人体是否患有疾病进行早期诊断,但由于视网膜中的血管错综复杂,模型在分割时会出现对微细血管分割精确度不足的问题。为此,提出一种结合残差模块Res2-net以及高效通道注意力机制(efficient channel attention,ECA)的D-Linknet模型。首先,利用Res2-net代替基础模型中的残差模块Res-net以提升每个网络层的感受野;其次,在Res2-net中添加一种结合压缩激励(squeeze and excitation,SE)和门通道(gated channel transformation,GCT)的注意力机制模块,改善处于复杂背景下的血管分割效果和效率;在网络的解码层加入ECA确保模型计算的性能,避免因降维导致的精度下降;最后,融合改进的模型输出图与掩膜图细化分割结果。在公开数据集DRIVE、STARE上进行分割实验,模型准确度(accuracy,AC)分别为97.11%、96.32%,灵敏度(sensitivity,SE)为84.55%、83.92%,曲线下方范围的面积(area under curve,AUC)为0.9873和0.9766,分割效果优于其他模型。实验证明了算法的可行性,为后续研究提供科学依据。展开更多
基金National Natural Science Foundation of China under Grant No.61973037China Postdoctoral Science Foundation 2022M720419 to provide fund for conducting experiments。
文摘The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs.
基金funding support from the National Major Research and Development Program(2019YFB2203603)the National Science Fund for Distinguished Young Scholars(61725503)+2 种基金the National Natural Science Foundation of China(NSFC)(62275273,11804387,and 91950205)the China Postdoctoral Science Foundation(2020M681847)the Zhejiang Provincial Natural Science Foundation(LZ18F050001).
文摘Waveguide-integrated optical modulators are indispensable for on-chip optical interconnects and optical computing.To cope with the ever-increasing amount of data being generated and consumed,ultrafast waveguide-integrated optical modulators with low energy consumption are highly demanded.In recent years,two-dimensional(2D)materials have attracted a lot of attention and have provided tremendous opportunities for the development of high-performance waveguide-integrated optical modulators because of their extraordinary optoelectronic properties and versatile compatibility.This paper reviews the state-of-the-art waveguide-integrated optical modulators with 2D materials,providing researchers with the developing trends in the field and allowing them to identify existing challenges and promising potential solutions.First,the concept and fundamental mechanisms of optical modulation with 2D materials are summarized.Second,a review of waveguide-integrated optical modulators employing electro-optic,all-optic,and thermo-optic effects is provided.Finally,the challenges and perspectives of waveguide-integrated modulators with 2D materials are discussed.
文摘目的分析2型糖尿病患者25-羟维生素D[25(OH)D]水平,初步了解血清25(OH)D水平与2型糖尿病患者糖化血红蛋白(HbA1c)、胰岛功能等代谢指标的相关性。方法选择新乡市第一人民医院内分泌科2020年1月至2020年12月收治的459例2型糖尿病患者为研究对象。收集患者的临床资料,包括性别、年龄、血清25(OH)D、空腹胰岛素、C肽、HbA1c、空腹血糖、餐后血糖、尿微量白蛋白、尿白蛋白肌酐比值、血钙、血尿酸(UA)、三酰甘油(TG)、总胆固醇(TCH)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)等。根据血清25(OH)D水平将患者分为充足组[n=20,25(OH)D≥30μg·L^(-1)]、不足组[n=95,20μg·L^(-1)≤25(OH)D<30μg·L^(-1)]、缺乏组[n=231,10μg·L^(-1)≤25(OH)D<20μg·L^(-1)]、严重缺乏组[n=113,25(OH)D<10μg·L^(-1)]。比较4组患者各代谢指标的差异,采用Pearson相关分析25(OH)D与各代谢指标的相关性。结果2型糖尿病患者血清25(OH)D水平为3.00~46.59(15.75±0.35)μg·L^(-1),男性患者的血清25(OH)D水平显著高于女性患者(P<0.05)。2型糖尿病患者25(OH)D缺乏的患病率为74.9%(344/459),25(OH)D缺乏主要发生在1、2、3、4、11、12月份。不足组、缺乏组和严重缺乏组患者HbA1c显著高于充足组(P<0.05),缺乏组和严重缺乏组患者HbA1c显著高于不足组(P<0.05);缺乏组和严重缺乏组患者HbA1c比较差异无统计学意义(P>0.05)。充足组与不足组、缺乏组与严重缺乏组患者空腹血糖比较差异无统计学意义(P>0.05);缺乏组和严重缺乏组患者空腹血糖显著高于充足组、不足组(P<0.05)。充足组、不足组、缺乏组患者空腹胰岛素、尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值比较差异无统计学意义(P>0.05);严重缺乏组患者空腹胰岛素显著低于充足组、不足组和缺乏组,尿微量白蛋白、日尿白蛋白总量、尿白蛋白肌酐比值显著高于充足组、不足组和缺乏组(P<0.05)。4组患者的稳态模型评估的胰岛素抵抗指数(HOMA-IR)、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙比较差异均无统计学意义(P>0.05)。Pearson相关性分析结果显示,2型糖尿病患者血清25(OH)D水平与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关(r=-0.093、-0.166、-0.157,P<0.05),与空腹胰岛素呈正相关(r=0.089,P<0.05)。2型糖尿病患者血清25(OH)D水平与空腹血糖、HOMA-IR、血清白蛋白、血肌酐、餐后1 h血糖、餐后2 h血糖、餐后3 h血糖、空腹C肽、餐后1 h C肽、餐后2 h C肽、餐后3 h C肽、TG、TCH、LDL、HDL、血UA、血钙等无相关性(P>0.05)。结论2型糖尿病患者25(OH)D缺乏与不足普遍存在,女性患者缺乏更明显。2型糖尿病患者25(OH)D水平与空腹胰岛素呈正相关,与HbA1c、尿微量白蛋白、尿白蛋白肌酐比值呈负相关,25(OH)D缺乏的2型糖尿病患者主要分布在1、2、3、4、11、12月份。
文摘临床医生可通过观察眼底视网膜血管及其分支对人体是否患有疾病进行早期诊断,但由于视网膜中的血管错综复杂,模型在分割时会出现对微细血管分割精确度不足的问题。为此,提出一种结合残差模块Res2-net以及高效通道注意力机制(efficient channel attention,ECA)的D-Linknet模型。首先,利用Res2-net代替基础模型中的残差模块Res-net以提升每个网络层的感受野;其次,在Res2-net中添加一种结合压缩激励(squeeze and excitation,SE)和门通道(gated channel transformation,GCT)的注意力机制模块,改善处于复杂背景下的血管分割效果和效率;在网络的解码层加入ECA确保模型计算的性能,避免因降维导致的精度下降;最后,融合改进的模型输出图与掩膜图细化分割结果。在公开数据集DRIVE、STARE上进行分割实验,模型准确度(accuracy,AC)分别为97.11%、96.32%,灵敏度(sensitivity,SE)为84.55%、83.92%,曲线下方范围的面积(area under curve,AUC)为0.9873和0.9766,分割效果优于其他模型。实验证明了算法的可行性,为后续研究提供科学依据。
