On an Application of the Improved Maximum Product Criterion to Inverse Acoustic Scattering in a Layered Medium

In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known factorization method, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a mixed reciprocity principle, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called Improved Maximum Product Criterion (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no a priori knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples.

基于改进模糊综合评价法的水库移民生产生活水平评价

为查清辽宁省水库移民生产生活水平现状,并对其合理评价以指导后期扶持政策实行,根据2005-2012年辽宁省水库移民、原住民、农村居民生产生活统计数据,应用改进的模糊综合评价法,采用组合权重,通过最大隶属原则的有效度及置信度准则判定水库移民生产生活水平等级。结果表明,水库移民后期扶持政策实施后,辽宁省水库移民生产生活水平提高,后期扶持效果显著。与原住民生产生活水平相比几无差距,与农村居民尚存在一定差距。目前,人均纯收入、人均住房面积、住房结构、人均耕地面积、成人平均受教育年限5个指标为造成差距的主要影响因素。