声速的

The phylogeny and applied prospect of MES are summarized in the paper. The principle of this system is analyzed from the point of view of acoustics. The surveying and filtering technology of auxiliary parameters, sounding data and the theory of image form, backscatter strength data processing, are researched deeply in the paper. The optimal model of velocity of sound is given. For sound ray tracing, some methods of correction of sound ray curve are developed. At the same time, an ideal model of sound ray tracing is proved and given. The GPS technology is applied for the determination of tide, attitude of vessel. Moreover, some methods are given. As an important topic, the systematic error is discussed in the paper. Some filtering methods are researched in this paper. Based on the current methods of image processing, the procedure and methods are tested and given that adapt to sonar image processing.

本文研究的工作是在总结多波束声纳测深系统的发展历史、应用前景的基础上，从声学角度分析了多波束系统的工作原理；对多波束辅助参数的测定和滤波方法、测深数据的滤波方法、多波束声纳图像的形成机理、图像处理以及最终应用等作了比较深入的研究；得出了适合于多波束精密深度计算的最优声速模型和声线改正模型；提出了 GPS 载波相位定位技术用于多波束辅助参数测量的思想、算法，改善了多波束系统的作业模式；系统地分析了深度数据的误差来源和类型，首次将系统误差作为影响测深精度的主要因素给以研究，并给出了削弱系统误差的方法，提高了深度数据的质量；对多波束声纳图像的形成、处理方法进行了细致的研究，给出了适合多波束图像处理的算法和流程，并从理论和实践上对声纳图像的应用进行了比较全面的研究。

Through 2D axial symmetrical and 3D scarfed reversal nozzle calculating, the main flowfield characters were given, and compared with the experiment data for validation. Then, the program was given, which can well predict the performance of the scarfed reversal nozzle. In this paper, the flowfields of open cavities with different structures and different parameters were calculated. Some new, full and more reasonable mechanism interprets were given. We think that the essential cause of pressure oscillatory is coherent effect of wave, eddy and cavity structure, but the procedure is different with different cavity structure, it can not use single procedure to described.

通过对二维轴对称和三维斜切反喷管的计算分析，本文给出了流场的主要特征，并采用实验数据进行了验证，形成了分析斜切反喷管可靠的应用方法；本文通过对不同结构形式、不同参数的二维、三维非定常超声速开式空腔流动进行的计算分析，提出了较为全面、合理的空腔压力振荡循环机理的解释，本文认为压力脉动本质上是波、涡以及结构之间相互的干扰和耦合，但干扰的具体过程随空腔结构的不同差别较大，不能采用单一的规律进行描述。

The good design of this device is very important to accomplish flow control and stability of the aircraft construct. The contour of scarfed reversal nozzle has many discontinuous points and a step at supersonic zone. So it can generate a series of expand waves and shock waves, and accomplished with flows separation and reattach.

斜切反喷管作为导弹常用的推力终止装置，能够可靠地完成发动机与有效载荷的分离，它的设计水平对提高导弹命中精度和武器装备的作战性能尤为重要；超声速开式空腔作为流动控制装置，具有减小阻力、增加燃烧混合、延缓边界层分离等作用，但同时也会带来严重的压力波动和噪声，其合理的设计对流动控制的实现以及飞行器结构的稳定性至关重要。

Moreover, the accuracy analysis for different measurements and parameters(such as time measure error, azimuth measure error, buoys error, baseline length and sound velocity fluctuation) are given respectively. To make the best use of the observation datas, the weighted least square localization algorithm is used to improve the accuracy in bistatic sonar. The simulation results show that the positioning accuracy of this algorithm is higher than the other four algorithms, with which the positioning accuracy in stations areas and side areas can be improved effectively.

同时，通过对系统各个因素，如系统的各观测量的测量误差、站址误差、基线长度、声速波动等参数对算法性能的影响，得出了各方法定位误差的分布规律；为了充分利用双基地声纳系统的观测数据，提高系统的定位精度，采用加权最小二乘方法对系统的数据进行优化处理，仿真结果表明该方法定位精度明显高于基本方法的定位精度，能有效的改善发射站和接受站侧边区的定位精度，且定位性能受站址测量误差的影响较小。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。