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81.
Emily M. Craparo Armin Fügenschuh Christoph Hof Mumtaz Karatas 《European Journal of Operational Research》2019,272(3):816-831
Multistatic sonar networks consisting of non-collocated sources and receivers are a promising development in sonar systems, but they present distinct mathematical challenges compared to the monostatic case in which each source is collocated with a receiver. This paper is the first to consider the optimal placement of both sources and receivers to monitor a given set of target locations. Prior publications have only considered optimal placement of one type of sensor, given a fixed placement of the other type. We first develop two integer linear programs capable of optimally placing both sources and receivers within a discrete set of locations. Although these models are capable of placing both sources and receivers to any degree of optimality desired by the user, their computation times may be unacceptably long for some applications. To address this issue, we then develop a two-step heuristic process, Adapt-LOC, that quickly selects positions for both sources and receivers, but with no guarantee of optimality. Based on this, we also create an iterative approach, Iter-LOC, which leads to a locally optimal placement of both sources and receivers, at the cost of larger computation times relative to Adapt-LOC. Finally, we perform computational experiments demonstrating that the newly developed algorithms constitute a powerful portfolio of tools, enabling the user to slect an appropriate level of solution quality, given the available time to perform computations. Our experiments include three real-world case studies. 相似文献
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The accuracy of the acoustical method used in quantitative assessment of fish populations is mainly dependent on the measurement of the time varying echo signals and the evaluation of the fish target strengths. Various types of accumulative uncertainties involved in the measurement and estimation of different physical variables associated with the two way propagation of the acoustic signals between the fish target and the echo sounder system are investigated in this paper. The accumulative uncertainties are so high that an attempt to obtain an accuracy of, say, 0.5 dB in the conventional target strength calibration routines would have little meaning for any practical fishstock assessment survey. A new dynamic calibration method is proposed and discussed. 相似文献
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In this paper, we extend the concept of kings and serfs in tournaments to that of weak kings and weak serfs in oriented graphs.
We obtain various results on the existence of weak kings (weak serfs) in oriented graphs, and show the existence of n-oriented graphs containing exactly k weak kings (weak serfs), 1 ≤ k ≤ n. Also, we give the existence of n-oriented graphs containing exactly k weak kings and exactly s weak serfs such that b weak kings from k are also weak serfs.
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单基地合成孔径声呐成像通常基于点目标假设,其相干积累处理不能克服分布型目标散射模式的起伏效应。收发异置的双基地声呐可以从不同角度观察目标,充分挖掘目标散射模式的角度依赖特性,在对水下目标(尤其人造目标)检测与定位方面,相对仅仅观测后向散射的单基地声呐有潜在的优势。该文 介绍一种基于自主水下航行器的双基地合成孔径声呐系统,重点介绍湖试成像的结果,验证双基地合成孔径声呐的可行性。同时通过引入目标散射模式建模的宽角度合成孔径声呐处理,实现了对目标探测性能的提升。 相似文献