The present work is an analytical study of the influence of geometrical parameters, such as length, thickness and immersion of the plate, on the reflection coefficient of a regular wave for an immersed horizontal plat...The present work is an analytical study of the influence of geometrical parameters, such as length, thickness and immersion of the plate, on the reflection coefficient of a regular wave for an immersed horizontal plate in the presence of a uniform current with the same direction as the propagation of the incident regular wave. This study was performed using the linearized potential theory with the evanescent modes while searching for complex roots to the dispersion equation that are neither pure real nor pure imaginary. The results show that the effects of the immersion and the relative length on the reflection coefficient of the plate are accentuated by the presence of the current, whereas the plate thickness practically does not have an effect if it is relatively small.展开更多
提出了一种用交叉模型交叉模态(Cross Model Cross Mode,CMCM)方法与L1正则化结合的损伤识别方法。首先介绍了CMCM方法的基本原理,以及L2正则化与L1正则化的特点。然后通过一个实验室的钢框架结构对提出的方法进行了验证。结果表明,CMC...提出了一种用交叉模型交叉模态(Cross Model Cross Mode,CMCM)方法与L1正则化结合的损伤识别方法。首先介绍了CMCM方法的基本原理,以及L2正则化与L1正则化的特点。然后通过一个实验室的钢框架结构对提出的方法进行了验证。结果表明,CMCM方法与L2正则化结合容易造成非损伤单元的误判,而在CMCM方法中使用L1正则化则能更准确地识别结构的损伤。即使仅用第一阶测量模态,用L1正则化技术求解CMCM方程也能很准确地识别框架结构的损伤。展开更多
Concentration of fluorine in typical coals from China have been determined by half-fusion/fluoride-ion selective electrode method (FISE) The distribution regularities of fluorine in coals have been obtained The correl...Concentration of fluorine in typical coals from China have been determined by half-fusion/fluoride-ion selective electrode method (FISE) The distribution regularities of fluorine in coals have been obtained The correlation between fluorine and ash, fluorine and phosphorus and their probable mode of occurrence in coals have been quantitatively analyzed and discussed respectively It was observed that fluorine concentrations in Chinese coals approximately follow logarithmic statistics normal distribution The fluorine concentration ranges between 17 and 3088 μg/g and mean value is close to 200 μg/g The fluorine concentration increases with the ash content of the sample and the coal rank Fluorine is mainly present in mineral species, but fluoraptite is not the principal hose for fluorine in the coals studied The results will be of significance for combustion, conversion and pollution control of fluorine during coal展开更多
文摘The present work is an analytical study of the influence of geometrical parameters, such as length, thickness and immersion of the plate, on the reflection coefficient of a regular wave for an immersed horizontal plate in the presence of a uniform current with the same direction as the propagation of the incident regular wave. This study was performed using the linearized potential theory with the evanescent modes while searching for complex roots to the dispersion equation that are neither pure real nor pure imaginary. The results show that the effects of the immersion and the relative length on the reflection coefficient of the plate are accentuated by the presence of the current, whereas the plate thickness practically does not have an effect if it is relatively small.
文摘提出了一种用交叉模型交叉模态(Cross Model Cross Mode,CMCM)方法与L1正则化结合的损伤识别方法。首先介绍了CMCM方法的基本原理,以及L2正则化与L1正则化的特点。然后通过一个实验室的钢框架结构对提出的方法进行了验证。结果表明,CMCM方法与L2正则化结合容易造成非损伤单元的误判,而在CMCM方法中使用L1正则化则能更准确地识别结构的损伤。即使仅用第一阶测量模态,用L1正则化技术求解CMCM方程也能很准确地识别框架结构的损伤。
基金国家自然科学基金! (No :598760 36)浙江省自然科学基金! (No :5960 97)国家重点基础研究发展规划项目!(G1 9990 2 2 2 1 1 )资助
文摘Concentration of fluorine in typical coals from China have been determined by half-fusion/fluoride-ion selective electrode method (FISE) The distribution regularities of fluorine in coals have been obtained The correlation between fluorine and ash, fluorine and phosphorus and their probable mode of occurrence in coals have been quantitatively analyzed and discussed respectively It was observed that fluorine concentrations in Chinese coals approximately follow logarithmic statistics normal distribution The fluorine concentration ranges between 17 and 3088 μg/g and mean value is close to 200 μg/g The fluorine concentration increases with the ash content of the sample and the coal rank Fluorine is mainly present in mineral species, but fluoraptite is not the principal hose for fluorine in the coals studied The results will be of significance for combustion, conversion and pollution control of fluorine during coal