Orthogonal time frequency space(OTFS)technique, which modulates data symbols in the delayDoppler(DD) domain, presents a potential solution for supporting reliable information transmission in highmobility vehicular net...Orthogonal time frequency space(OTFS)technique, which modulates data symbols in the delayDoppler(DD) domain, presents a potential solution for supporting reliable information transmission in highmobility vehicular networks. In this paper, we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler. We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing(UAMP), which exploits the structured sparsity of the effective DD domain channel using hidden Markov model(HMM). The empirical state evolution(SE) analysis is then leveraged to predict the performance of our proposed algorithm. To refine the hyperparameters in the proposed algorithm,we derive the update criterion for the hyperparameters through the expectation-maximization(EM) algorithm. Finally, Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes.展开更多
目的探讨通心络胶囊对进展型缺血性脑卒中患者血清糖基化终产物(advanced glycation end products,AGE)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)、总抗氧化能力(Total antioxidant capacity,T-AOC)水...目的探讨通心络胶囊对进展型缺血性脑卒中患者血清糖基化终产物(advanced glycation end products,AGE)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)、总抗氧化能力(Total antioxidant capacity,T-AOC)水平的影响。方法选取诊治的进展型缺血性脑卒中患者60例,随机分为对照组与实验组,每组30例,对照组进行常规综合治疗,实验组在常规综合治疗基础上给予通心络胶囊口服治疗,两组均治疗14 d,观察治疗前后血清AGE、MDA、SOD、T-AOC水平、神经功能缺损严重程度,并对治疗疗效进行评估。结果两组治疗前血清AGE、MDA、SOD、T-AOC水平比较差异无统计学意义(P>0.05),AGE、MDA后较治疗前均下降(P<0.05),且实验组下降幅度大于对照组(P<0.05),SOD、T-AOC治疗后较治疗前升高(P<0.05),且实验组升高幅度大于对照组(P<0.05);两组治疗前美国国立卫生院卒中量表(National Institutes of Health Stroke Scale,NIHSS)及格拉斯哥昏迷指数(Glasgow Coma Scale,GCS)评分比较差异无统计学意义(P>0.05),NIHSS评分治疗后较治疗前均下降(P<0.05),且实验组下降幅度大于对照组(P<0.05),GCS评分治疗后较治疗前升高(P<0.05),且实验组升高幅度大于对照组(P<0.05);对照组与实验组的治疗总有效率分别为73.33%(22/30)、93.33%(28/30),比较差异有统计学意义(P<0.05);Sperman相关性分析显示,进展型缺血性脑卒中患者NIHSS评分与血清AGE和MDA水平呈显著正相关(P<0.05),与SOD和T-AOC水平呈显著负相关(P<0.05),患者GCS评分与血清AGE和MDA水平呈显著负相关(P<0.05),与SOD和T-AOC水平呈显著正相关(P<0.05)。结论进展型缺血性脑卒中患者血清AGE、MDA、SOD、T-AOC水平与神经功能缺损密切相关,采用通心络胶囊治疗可有效改善患者血清AGE、MDA、SOD、T-AOC水平,促进患者神经功能的改善,提高疗效。展开更多
基金supported by the Key Scientific Research Project in Colleges and Universities of Henan Province of China(Grant Nos.21A510003)Science and the Key Science and Technology Research Project of Henan Province of China(Grant Nos.222102210053)。
文摘Orthogonal time frequency space(OTFS)technique, which modulates data symbols in the delayDoppler(DD) domain, presents a potential solution for supporting reliable information transmission in highmobility vehicular networks. In this paper, we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler. We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing(UAMP), which exploits the structured sparsity of the effective DD domain channel using hidden Markov model(HMM). The empirical state evolution(SE) analysis is then leveraged to predict the performance of our proposed algorithm. To refine the hyperparameters in the proposed algorithm,we derive the update criterion for the hyperparameters through the expectation-maximization(EM) algorithm. Finally, Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes.
文摘目的探讨通心络胶囊对进展型缺血性脑卒中患者血清糖基化终产物(advanced glycation end products,AGE)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)、总抗氧化能力(Total antioxidant capacity,T-AOC)水平的影响。方法选取诊治的进展型缺血性脑卒中患者60例,随机分为对照组与实验组,每组30例,对照组进行常规综合治疗,实验组在常规综合治疗基础上给予通心络胶囊口服治疗,两组均治疗14 d,观察治疗前后血清AGE、MDA、SOD、T-AOC水平、神经功能缺损严重程度,并对治疗疗效进行评估。结果两组治疗前血清AGE、MDA、SOD、T-AOC水平比较差异无统计学意义(P>0.05),AGE、MDA后较治疗前均下降(P<0.05),且实验组下降幅度大于对照组(P<0.05),SOD、T-AOC治疗后较治疗前升高(P<0.05),且实验组升高幅度大于对照组(P<0.05);两组治疗前美国国立卫生院卒中量表(National Institutes of Health Stroke Scale,NIHSS)及格拉斯哥昏迷指数(Glasgow Coma Scale,GCS)评分比较差异无统计学意义(P>0.05),NIHSS评分治疗后较治疗前均下降(P<0.05),且实验组下降幅度大于对照组(P<0.05),GCS评分治疗后较治疗前升高(P<0.05),且实验组升高幅度大于对照组(P<0.05);对照组与实验组的治疗总有效率分别为73.33%(22/30)、93.33%(28/30),比较差异有统计学意义(P<0.05);Sperman相关性分析显示,进展型缺血性脑卒中患者NIHSS评分与血清AGE和MDA水平呈显著正相关(P<0.05),与SOD和T-AOC水平呈显著负相关(P<0.05),患者GCS评分与血清AGE和MDA水平呈显著负相关(P<0.05),与SOD和T-AOC水平呈显著正相关(P<0.05)。结论进展型缺血性脑卒中患者血清AGE、MDA、SOD、T-AOC水平与神经功能缺损密切相关,采用通心络胶囊治疗可有效改善患者血清AGE、MDA、SOD、T-AOC水平,促进患者神经功能的改善,提高疗效。
