【摘 要】
:
In the light of the concept of spherical wave source, the theoretical model of nearfield acoustic holography (NAH) based on the spherical wave superposition met
【机 构】
:
Dynamic Measuring Center
论文部分内容阅读
In the light of the concept of spherical wave source, the theoretical model of nearfield acoustic holography (NAH) based on the spherical wave superposition method (SWSM), including reconstruction of expansion coefficients, prediction of acoustic field, error sensitivity analysis, regularization method and a searching method with dual measurement surfaces for determining the optimal number of expansion terms, is established. Subsequently, the spherical wave source boundary point method (SWSBPM) and its application in the NAH are introduced briefly. Considering the similarity of the SWSM and the SWSBPM for realizing the NAH, they are compared. The similarities and differences of the two methods are illuminated by a rigorous mathematical justification and two experiments on a single source and two coherent sources in the semi-free acoustic field. And, the superiority of the NAH based on the SWSBPM is demonstrated.
其他文献
Attempt has been made to discuss the coupling relation of neotectonism and paleoclimate that have played a critical role in controlling the Quaternary sediment
善意取得制度从日尔曼法起算,迄今已有较长的历史.国外对此有明确立法规定,我国在立法中虽无明确规定但在司法实践中早已获得承认.2007年3月通过的以法律的形式将善意取得制
随着计算机技术的快速发展,电子政务得到了长足的发展,同时,因为需求分析不当造成电子政务项目建设失败的比例也不断增大.本文通过需求分析概述,在电于政务中的需求分析实施
近年来我国相继推行部门预算和国库集中支付等财政改革,引起行政事业单位财务活动的重大变革,这就要求行政事业单位进一步加强内部控制以适应新时期的管理需要。本文就行政事
Variations of the particulate organic carbon and nitrogen (POC/PN) along the PN section in the East China Sea (ECS) were examined based on POC/PN data obtained
Experiments on the effects of nitric oxide (NO) and iron on the growth of marine microalgae Skeletonema costatum were conducted.The results are as follows: exog
Geochemical and isotopic investigations have been carried out on the Chebu gabbroite in southern Jiangxi Province, southeast China and these results are compare
Clay fractions in the non-calcareous surface sediments from the eastern Pacific were analyzed for clay minerals, REE and 143Nd/144Nd. Montmorillonite/illite rat
加强和改进大学生思想政治教育工作,必须从国内和国际、历史和现实的角度,深刻分析新时期大学生的思想活动发生作用的客观环境及其基本特点,正确审视新形势下那些影响大学生
Abundant phosphatized acritarchs are preserved in the late Precambrian (Ediacaran) Doushantuo Formation at Weng'an, Guizhou Province, southwest China. Most of t