检索结果-内蒙古大学图书馆

Verification of optimal discretization in multi-plane phaseless diagnostics

AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS 2023年 170卷

作者： Leone, Giovanni Masoodi, Mehdi Univ Campania Dept Engn I-81031 Aversa Italy

The paper deals with the reconstruction of the excitation coefficients of a planar array antenna from phaseless near-field data. To solve this non linear inverse problem, the iterative minimization of a non quadratic functional of the data by the conjugate gradient method is performed. A novel non- uniform measurement grid is applied to collect the data over a planar observation surface. According to the number of unknowns, i.e. the elements of the array source, the number of scanning planes is to be increased in order to achieve the solution. Therefore, a criterion providing the optimal distance between them is applied, leading to a non uniform spacing. Compared with a standard uniform spacing approach, array coefficients reconstructions are obtained by far less number of data with similar reliability. Finally, numerical results, including both noiseless and noisy conditions and a diagnostics application, prove the correctness and validity of the assumed mathematical findings.

关键词： Near field measurements Phaseless data non-linear inverse source problem Array Diagnostic

来源：评论

学校读者我要写书评

暂无评论

A non-iterative method for identifying multiple unknown time-dependent sources compactly supported occurring in a 2D parabolic equation

引用

inverse problemS IN SCIENCE AND ENGINEERING 2018年第5期26卷 744-772页

作者： Hamdi, Adel Inst Natl Sci Appl Rouen Lab Math LMI St Etienne Du Rouvray France

We address the non-linear inverse source problem of identifying multiple unknown time-dependent sources spatially supported in some subdomains of a two-dimensional bounded domain subject to an evolution advection-dispersion-reaction equation. Provided to be available within the monitored domain interfaces for recording the state and its flux crossing each suspected zone where a source could occur, we establish an identifiability theorem that yields uniqueness of the unknown elements defining all occurring sources. We develop a non-iterative detection-identification method that goes throughout the monitored domain to detect in each suspected zone whether there exists or not an occurring source. Once a source is detected, the developed method determines lower and upper bounds of the total amount discharged by the occurring source and localizes the geometric centre of its unknown spatial support. Then, given two desired reference geometries for example, squares/discs centred at the already localized geometric centre, the method determines the biggest domain defined by a first reference geometry included in the sought source spatial support as well as the smallest domain defined by a second reference geometry containing this unknown support. In addition, the developed method gives an approximation of the surface area of this latest and identifies its time-dependent intensity function. Some numerical experiments on a variant of the surface water Biological Oxygen Demand pollution model are presented.

关键词： non-linear inverse source problem rough partial shape identification optimization and control advection-dispersion-reaction equation

来源：评论

学校读者我要写书评

暂无评论

Detection-Identification of multiple unknown time-dependent point sources in a 2D transport equation: application to accidental pollution

引用

inverse problemS IN SCIENCE AND ENGINEERING 2017年第10期25卷 1423-1447页

作者： Hamdi, Adel Inst Natl Sci Appl Rouen Lab Math LMI Ave Univ St Etienne Du Rouvray France

We address the nonlinear inverse source problem of identifying multiple unknown time-dependent point sources occurring in a two-dimensional evolution advection-dispersion-reaction equation. Provided to be available within the monitored domain interfaces for recording the generated state and its flux crossing each suspected zone where a source could occur, we establish a constructive identifiability theorem based on an introduced dispersion-current function that yields uniqueness of the unknown elements defining all occurring sources. Then, the established theorem leads to develop a detection-identification method that goes throughout the monitored domain to detect in each suspected zone whether there exists or not an occurring source. Once a source is detected, the developed method determines lower and upper bounds of the mean value discharged by its unknown time-dependent intensity function. Thereafter, the method localizes the sought position of the detected source as the unique solution of an equation satisfied by the introduced dispersion-current function and identifies its unknown intensity function from solving an associated deconvolution problem. Ultimately, the unknown number of occurring sources is deduced as the sum of all detected-identified active sources. Some numerical experiments on a variant of the surface water BOD pollution model are presented.

关键词： non-linear inverse source problem data assimilation optimization and control technique advection-dispersion-reaction equation surface water pollution

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：