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排序方式: 共有289条查询结果,搜索用时 140 毫秒
91.
提出了根据实测声速剖面,利用经验正交函数建立了声速剖面场的数学模型,得到了任意点位的声速剖面对边缘波束数据进行声线折射改正的方法。该方法对提高多波束勘测效率和精度具有重要意义。 相似文献
92.
在灌注桩施工过程中,常遇见有堵管事故发生,若能及时采用“二次剪球”法进行孔内接桩,就能稳妥地解决灌注桩施工中遇到的堵管事故。使工程保质保量,顺利完成。 相似文献
93.
主叫用户识别及其语音实现 总被引:1,自引:0,他引:1
介绍了主叫用户识别技术的基本原理 ,分析了其目前的几种实现方法 ,在此基础上提出了一种新颖的语音实现方案 ,给出了此方案的具体硬、软件设计 相似文献
94.
提出了一种基于正交直线麦克风阵列的分级搜索SRP-PHAT(可控响应功率-相位加权)语音定位算法.利用正交直线麦克风阵列将二维搜索空间缩减为2个一维空间以减少计算量,并联合使用四叉树由粗到细的分级搜索(hierarchical search)策略分别在一维空间中搜索声源位置.通过Matlab对联合算法进行了仿真,实现了声源定位,并与传统的全搜索SRP-PHAT算法和改进前的基于正交直线麦克风阵列的加速SRP-PHAT算法进行比较分析.实验与仿真结果显示:该联合算法大大减少了计算量和定位时间,能准确定位声源位置. 相似文献
95.
96.
Distributions and vertical variation patterns of sound speed of surface sediments in South China Sea
The distributions of sound speed show different characteristics in continental shelf, continental slope and Nansha Trough. The differences have closely related to the distributions of sediment physical properties in the southern South China Sea. According to the analysis of sound speeds and physical properties variation characteristics with buried depth, the vertical variations of sound speed are closely related to sediment texture, sedimentary environment, transport, erosion, compaction, consolidation, etc. The comparison results indicate 3 vertical variation patterns of sound speed: increasing model, invariant model and complicate variation model. The above 3 variation models represent the vertical distribution characteristics of sound speed in different depositional environments. Different variation patterns have different key factors which generally contain porosity or grain size. The calculated sound speeds with Buckingham’s theory of compressional waves in fluid-like marine sediments follows the trend of measured speeds accurately. 相似文献
97.
Complex perturbations in the profile and the sparsity of samples often limit the validity of rapid environmental assessment (REA) in the South China Sea (SCS). In this paper, the remote sensing data were used to estimate sound speed profile (SSP) with the self-organizing map (SOM) method in the SCS. First, the consistency of the empirical orthogonal functions was examined by using k-means clustering. The clustering results indicated that SSPs in the SCS have a similar perturbation nature, which means the inverted grid could be expanded to the entire SCS to deal with the problem of sparsity of the samples without statistical improbability. Second, a machine learning method was proposed that took advantage of the topological structure of SOM to significantly improve their accuracy. Validation revealed promising results, with a mean reconstruction error of 1.26 m/s, which is 1.16 m/s smaller than the traditional single empirical orthogonal function regression (sEOF-r) method. By violating the constraints of linear inversion, the topological structure of the SOM method showed a smaller error and better robustness in the SSP estimation. The improvements to enhance the accuracy and robustness of REA in the SCS were offered. These results suggested a potential utilization of REA in the SCS based on satellite data and provided a new approach for SSP estimation derived from sea surface data. 相似文献
98.
99.
大气非静力数值模式中声波的阻尼和压缩 总被引:1,自引:0,他引:1
介绍大气非静力弹性模式中声波的阻尼和压缩方法,分析和模拟试验的结果表明,声波的阻尼和压缩能够对模式的解的振幅起到一定的衰减作用,有利于保证模式的计算稳定性和减少计算量。. 相似文献
100.
《The Cartographic journal》2013,50(4):332-344
AbstractAlong with an increasing importance and awareness of sonic phenomena related to the human environment, there is a growing need for a comprehensive communication of sound information. The central goal of this contribution is the development of a systematic and comprehensive framework that considers the particular properties of sound phenomena. This framework is structured according to the acoustic quantities that shall be represented and consists of recommendations for their cartographical encoding. A proof of concept is given through the application to official strategic noise maps in the course of the Environmental Noise Directive. Those maps suffer from several weaknesses from a cartographical point of view (e.g. concerning colour schemes or band-like illustrations) which can be eliminated by applying some of the mentioned recommendations. Finally, it will be possible to derive valuable knowledge from our results for multimodal encoding and value transformation between senses. 相似文献