探索渡口安全管理长效机制

亳州市谯城区交通局和亳州市直属海事处,因地制宜地认真研究贯彻落实全国全省电视电话动员会精神。以开展渡口渡船专项整治活动为契机,积极探索建立确保渡口源头安全管理长治久安举措,研制出台《毫州市谯城区渡口设置安全管理规定》,在安徽省率先创新实施渡口源头安全管理长效机制。     

潮州三百门电厂煤港工程海岸动力地貌特征分析

根据现场地貌踏勘及拟建煤港工程近海区表层底质样品的粒度分析结果,结合前人的研究成果,对近海区的泥沙来源及运移趋势、港口建设的泥沙条件等给予了分析评价。     

中国沿海南北线的气象资料源

分析和评价了在中国沿海南北线航行船舶可以利用的气象资料和气象资料源。本文首先分析了气候资料、天气报告、天气图、天气雷达图和船舶实测资料在天气分析和预报中的应用;然后分析了主要资料源,除了传统的NAVTEX和气象传真机外,现在船舶还可以利用互联网,获得更丰富的气象资料。     

Research on the coefficient of sound absorption in turbid water

China’s coastal waters are turbid and the properties of the seabed are complex. This negatively impacts the performance of underwater detection equipment. The properties of sound absorption in turbid water are not well understood. In this paper, the coefficient of sound absorption in turbid water was measured by the reverberation technique. All work was done in a reverberation barrel made of seamless aluminum. First, pure water was poured into the reverberation barrel and its reverberation time measured. Next, various concentrations of turbid water were poured into the barrel and their reverberation time measured. After all data had been gathered, the coefficient of sound absorption in turbid water of different concentrations was calculated. From this we determined a law of sound absorption in turbid water as summarized in the paper.     

关于高频开关电源的干扰及对抗措施

本文较为详细地分析了高频开关电源产生的电磁噪声及其对自身和邻近电子设备造成的干扰，并提出了一些抑制干扰的措施。实践证明，这些措施是行之有效的。     

舰船辐射噪声总声级及总能量的统计分析

在相同工况下,对于某一舰船辐射噪声总声级和总能量的多次测量结果来说,总声级的直方图分布比较对称,而总能量的直方图分布不对称.本文假设该舰船辐射噪声总声级多次测量值满足正态分布,利用非参数假设检验中的皮尔逊x2拟合检验和柯尔莫哥洛夫检验分别对其进行验证分析.结果表明,在显著性水平α较小时,总声级近似服从正态分布,进而得出总能量服从对数正态分布.结论在一定程度上给出了该舰船辐射噪声总声级及总能量的取值范围.     

一种水下等离子体声源充放电控制系统设计

介绍一种水下等离子体声源充放电控制系统的设计方案,能为水下强声源干扰对抗控制提供一种解决途径,设计的充放电控制系统能实现对多个等离子体声源的充放电进行远程操控,并监控工作状态。控制系统设计上选取高精度器件,并采取了一系列防护措施,以适应复杂的工作条件,并满足微秒级高精度时序控制要求。     

运用弹性理论研究有限长圆柱壳声辐射的一个通用方法(英文)

A general method was proposed to study the sound and vibration of a finite cylindrical shell with elastic theory.This method was developed through comprehensive analysis of the uncoupled Helmholtz equation obtained by the decomposition of elastic equations and the structure of the solution of a finite cylindrical shell analyzed by thin shell theory.The proposed method is theoretically suitable for arbitrary thickness of the shell and any frequency.Also,the results obtained through the method can be used to determine the range of application of the thin shell theory.Furthermore,the proposed method can deal with the problems limited by the thin shell theory.Additionally,the method can be suitable for several types of complex cylindrical shell such as the ring-stiffened cylindrical shell,damped cylindrical shell,and double cylindrical shell.     

船舶辐射噪声声源匹配定量分析方法

随着近年来对船舶噪声重视的增加,确定各噪声源在辐射噪声中的组成和贡献就变得格外重要。本文利用码头单机噪声试验确定单台设备噪声特征,通过拟合得到噪声特征表达式,利用单机组合测试数据,确定各个单机在辐射噪声中的组成比例,综合确定各噪声源在辐射噪声中的组成和贡献。阐述了数值拟合和声源匹配理论,给出了计算方法,结合测量数据进行了拟合及匹配计算。通过测量结果和匹配结果的比较,证明了本方法的可行性。     

基于TPA的管路振动贡献量分析

针对工程实际中管路振动贡献量难以定量分析的问题,引入传递路径分析法(TPA)。通过测量各路径的频率响应函数、各安装点和评估点的响应以及估算激励力,进行传递路径分析,进而得到设备与管路各自的贡献量。通过用某型海水泵进行实验,验证了该方法的准确性。实验结果表明,在40～200 Hz频段内,采用该方法得到的响应计算值与测量值误差小于3 dB,满足工程实际要求。