Terrain matching accuracy and real-time performance are affected by local underwater terrain features and structure of matching surface. To solve the extraction problem of local terrain features for underwater terrain-aided navigation (UTAN), real-time data model and selection method of beams are proposed. Then, an improved structure of terrain storage is constructed, and a fast interpolation strategy based on index is proposed, which can greatly improve the terrain interpolation–reconstruction speed. Finally, for the influences of tide, an elimination method of reference depth deviation is proposed, which can reduce the reference depth errors caused by tidal changes. As the simulation test shows, the proposed method can meet the requirements of real-time performance and effectiveness. Furthermore, the extraction time is considerably reduced, which makes the method suitable for the extraction of local terrain features for UTAN.
苦橄岩和科马提岩都是富镁的超镁铁质火山岩，早先，学术界大多关注它们之间的相似性，而对于它们之间的差异性很少强调。于是认为二者的地球化学性质近似，成因类似，形成条件类似。本文采用全数据模式的研究方法，从数据库收集了全球太古宙全部科马提岩和后太古宙全部苦橄岩数据，对比的结果表明，太古宙科马提岩与后太古宙苦橄岩完全不同，它们之间几乎没有可比性。科马提岩与苦橄岩，不仅地球化学特征不同，而且成因不同，形成条件不同，产出时代不同，源区组成也不同。这种不同，反映了太古宙和后太古宙不可能属于同样的构造体制。太古宙是火球时代，地球异常的热，主导的可能是静止盖幔构造（stagnant lid tectonics）；后太古宙是热球时代，地球相对冷了许多，主导的是板块构造（plate tectonics）。科马提岩在太古宙广泛出露，无需地幔柱模式；而苦橄岩在后太古宙很少出露，才真正需要地幔柱模式。
The cadmium sulphide (CdS) film is grown on cadmium telluride (CdTe) nanorods (NRs) arrays by different methods such as chemical bath deposition (CBD), magnetron sputtering (MS), and homogenous precipitation (HP) techniques. The impact of various deposition methods is explored in detail on the growth of CdTe/CdS composite film, the CdTe/CdS interface property, and solar cell efficiency. Compared to the CBD and HP methods, the MS method can improve the growth of the CdS on CdTe NRs with high crystalline quality. The device based on the CdS film prepared by the MS method demonstrates excellent photovoltaic performance, which has the potential for applications in solar cells.
