The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics ...The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics from the tsunami records at 21 Deep-ocean Assessment and Reporting of Tsunami(DART)sites and 29 coastal tide gauge stations.The results revealed systematic travel time delay of as much as 22 min(approximately 1.7%of the total travel time)relative to the simulated long waves from the 2015 Chilean tsunami.The delay discrepancy was found to increase with travel time.It was difficult to identify the LNP from the near-shore observation system due to the strong background noise,but the initial negative phase feature became more obvious as the tsunami propagated away from the source area in the deep ocean.We determined that the LNP for the Chilean tsunami had an average duration of 33 min,which was close to the dominant period of the tsunami source.Most of the amplitude ratios to the first elevation phase were approximately 40%,with the largest equivalent to the first positive phase amplitude.We performed numerical analyses by applying the corrected long wave model,which accounted for the effects of seawater density stratification due to compressibility,self-attraction and loading(SAL)of the earth,and wave dispersion compared with observed tsunami waveforms.We attempted to accurately calculate the arrival time and LNP,and to understand how much of a role the physical mechanism played in the discrepancies for the moderate transoceanic tsunami event.The mainly focus of the study is to quantitatively evaluate the contribution of each secondary physical effect to the systematic discrepancies using the corrected shallow water model.Taking all of these effects into consideration,our results demonstrated good agreement between the observed and simulated waveforms.We can conclude that the corrected shallow water model can reduce the tsunami propagation speed and reproduce the LNP,which is observed for tsunamis that展开更多
目的 比较全视网膜激光光凝术(PRP)联合不同药物(曲安奈德、康柏西普)对增生性糖尿病视网膜病变(PDR)患者视网膜厚度、最佳矫正视力(BCVA)及N1波潜伏期的影响。方法 前瞻性选取2016年9月至2018年6月86例PDR患者,均行PRP治疗,随机分为两...目的 比较全视网膜激光光凝术(PRP)联合不同药物(曲安奈德、康柏西普)对增生性糖尿病视网膜病变(PDR)患者视网膜厚度、最佳矫正视力(BCVA)及N1波潜伏期的影响。方法 前瞻性选取2016年9月至2018年6月86例PDR患者,均行PRP治疗,随机分为两组,对照组术前给予曲安奈德注射液治疗,研究组术前给予康柏西普注射液治疗,两组各43例。比较两组患者治疗前和治疗后1个月、3个月视网膜厚度、BCVA、N1波潜伏期波幅及术后并发症发生情况。结果 相比治疗前,两组患者治疗后1个月、3个月视网膜厚度均明显下降,且研究组治疗后视网膜厚度较对照组明显下降( P <0.05)。与治疗前相比,两组患者治疗后1个月、3个月BCVA均明显提高,且研究组治疗后BCVA较对照组明显提高( P <0.05)。治疗后1个月、3个月,两组患者N1波潜伏期波幅较治疗前均明显下降,且研究组治疗后的水平较对照组明显下降( P <0.05)。研究组术后视网膜脱离、眼高压及出血发生率为4.65%,较对照组的25.58%明显下降( P <0.05)。结论 在PRP治疗的情况下,相比曲安奈德,康柏西普不仅可有效降低PDR患者视网膜厚度,明显改善术后BCVA,矫正患者术后视力,改善视功能,而且可有效降低术后并发症的发生率,具有较高的用药安全性,因此值得临床应用。展开更多
对于求解波浪与大型结构物作用的pFFT方法,即预修正快速傅里叶变换方法(Pre-corrected Fast Fourier Transform),该文提出了消除"不规则频率"影响,从而保证在各频率下均可得到正确解的求解技术。该方法通过在内水面上配置源...对于求解波浪与大型结构物作用的pFFT方法,即预修正快速傅里叶变换方法(Pre-corrected Fast Fourier Transform),该文提出了消除"不规则频率"影响,从而保证在各频率下均可得到正确解的求解技术。该方法通过在内水面上配置源点的方法得到了唯一解的积分方程,并通过叠加物体内部积分方程而得到了便于求解的方形矩阵。算例表明:该方法能够消除"不规则频率"的影响,在整个频率内均可得到精确的计算结果;对于大型计算,在计算效率和内存空间的使用上,均较传统的高阶边界元方法有很大优势。展开更多
The behaviour of dilaton-gluon coupling （DGC） potential is investigated by studying charmonium spectra, annihilation rates and E1 transition rates systematically. We find that in the non-relativistic quantum chromod...The behaviour of dilaton-gluon coupling （DGC） potential is investigated by studying charmonium spectra, annihilation rates and E1 transition rates systematically. We find that in the non-relativistic quantum chromodynamics approximation, the charmonium properties can be described by the DGC potential.展开更多
基金The National Key Research and Development Program of China under contract Nos 2018YFC1407000 and2016YFC1401500the National Natural Science Foundation of China under contract Nos 41806045 and 51579090。
文摘The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics from the tsunami records at 21 Deep-ocean Assessment and Reporting of Tsunami(DART)sites and 29 coastal tide gauge stations.The results revealed systematic travel time delay of as much as 22 min(approximately 1.7%of the total travel time)relative to the simulated long waves from the 2015 Chilean tsunami.The delay discrepancy was found to increase with travel time.It was difficult to identify the LNP from the near-shore observation system due to the strong background noise,but the initial negative phase feature became more obvious as the tsunami propagated away from the source area in the deep ocean.We determined that the LNP for the Chilean tsunami had an average duration of 33 min,which was close to the dominant period of the tsunami source.Most of the amplitude ratios to the first elevation phase were approximately 40%,with the largest equivalent to the first positive phase amplitude.We performed numerical analyses by applying the corrected long wave model,which accounted for the effects of seawater density stratification due to compressibility,self-attraction and loading(SAL)of the earth,and wave dispersion compared with observed tsunami waveforms.We attempted to accurately calculate the arrival time and LNP,and to understand how much of a role the physical mechanism played in the discrepancies for the moderate transoceanic tsunami event.The mainly focus of the study is to quantitatively evaluate the contribution of each secondary physical effect to the systematic discrepancies using the corrected shallow water model.Taking all of these effects into consideration,our results demonstrated good agreement between the observed and simulated waveforms.We can conclude that the corrected shallow water model can reduce the tsunami propagation speed and reproduce the LNP,which is observed for tsunamis that
文摘目的 比较全视网膜激光光凝术(PRP)联合不同药物(曲安奈德、康柏西普)对增生性糖尿病视网膜病变(PDR)患者视网膜厚度、最佳矫正视力(BCVA)及N1波潜伏期的影响。方法 前瞻性选取2016年9月至2018年6月86例PDR患者,均行PRP治疗,随机分为两组,对照组术前给予曲安奈德注射液治疗,研究组术前给予康柏西普注射液治疗,两组各43例。比较两组患者治疗前和治疗后1个月、3个月视网膜厚度、BCVA、N1波潜伏期波幅及术后并发症发生情况。结果 相比治疗前,两组患者治疗后1个月、3个月视网膜厚度均明显下降,且研究组治疗后视网膜厚度较对照组明显下降( P <0.05)。与治疗前相比,两组患者治疗后1个月、3个月BCVA均明显提高,且研究组治疗后BCVA较对照组明显提高( P <0.05)。治疗后1个月、3个月,两组患者N1波潜伏期波幅较治疗前均明显下降,且研究组治疗后的水平较对照组明显下降( P <0.05)。研究组术后视网膜脱离、眼高压及出血发生率为4.65%,较对照组的25.58%明显下降( P <0.05)。结论 在PRP治疗的情况下,相比曲安奈德,康柏西普不仅可有效降低PDR患者视网膜厚度,明显改善术后BCVA,矫正患者术后视力,改善视功能,而且可有效降低术后并发症的发生率,具有较高的用药安全性,因此值得临床应用。
文摘对于求解波浪与大型结构物作用的pFFT方法,即预修正快速傅里叶变换方法(Pre-corrected Fast Fourier Transform),该文提出了消除"不规则频率"影响,从而保证在各频率下均可得到正确解的求解技术。该方法通过在内水面上配置源点的方法得到了唯一解的积分方程,并通过叠加物体内部积分方程而得到了便于求解的方形矩阵。算例表明:该方法能够消除"不规则频率"的影响,在整个频率内均可得到精确的计算结果;对于大型计算,在计算效率和内存空间的使用上,均较传统的高阶边界元方法有很大优势。
基金Supported partially by the National Natural Science Foundation of China under Grants Nos 10447130 and 10375074.
文摘The behaviour of dilaton-gluon coupling （DGC） potential is investigated by studying charmonium spectra, annihilation rates and E1 transition rates systematically. We find that in the non-relativistic quantum chromodynamics approximation, the charmonium properties can be described by the DGC potential.
