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Interference signals due to scattering from surface and reflecting from bottom is one of the most important problems of reliable communications in shallow water channels. To solve this problem, one of the best suggested ways is to use adaptive equalizers. Convergence rate and misadjustment error in adaptive algorithms play important roles in adaptive equalizer performance. In this paper, affine projection algorithm (APA), selective regressor APA(SR-APA), family of selective partial update (SPU) algorithms, family of set-membership (SM) algorithms and selective partial update selective regressor APA (SPU-SR-APA) are compared with conventional algorithms such as the least mean square (LMS) in underwater acoustic communications. We apply experimental data from the Strait of Hormuz for demonstrating the efficiency of the proposed methods over shallow water channel. We observe that the values of the steady-state mean square error (MSE) of SR-APA, SPU-APA0 SPU-normalized least mean square (SPU-NLMS), SPU-SR-APA0 SM-APA and SM-NLMS algorithms decrease in comparison with the LMS algorithm. Also these algorithms have better convergence rates than LMS type algorithm. 相似文献
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目的:探讨头针联合听觉统合训练治疗孤独症谱系障碍儿童听觉统合失调的临床疗效。方法:将60 例孤独症谱系障碍听觉统合失调患儿随机分为治疗组、对照1组、对照2组,每组各20 例。3组均予以综合康复训练,在此基础上对照1组予以听觉统合训练,对照2组予以头针治疗,治疗组予以头针联合听觉统合训练治疗。治疗40 d后观察3组的听觉注意能力测评情况、Gesell儿童发育量表评估情况(语言、个人-社交能区发育商值)、孤独症儿童行为量表(ABC)评分(感觉能力、交往能力、运动能力、语言能力、个人自理能力分值的差值)。结果:3组听觉注意能力测评情况及Gesell语言、个人-社交发育商值治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.05或P<0.01)。治疗后,3组感觉能力、交往能力、语言能力的差值比较,差异均有统计学意义(P<0.05)。结论:头针联合听觉统合训练能提高听觉统合失调孤独症患儿的疗效,能改善患儿的听觉注意力、语言、个人-社交及社会适应力。 相似文献
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