Three-dimensional search and height finding radar

The three-dimensional finite difference approximation of Mur's absorbing boundary condition is presented in frequency domain. With the discrete formulation of Maxwell's equation for finite difference frequency domain, it is convenient to solve three-dimensional electromagnetic scattering problem.

本文构造了三维Mur二阶吸收边界条件的频域差分离散格式，结合Maxwell方程组频域有限差分方程，可方便地分析三维电磁问题。

Numerical Solution of the Limited Aperture Problem in Three-Dimensional Inverse Acoustic Scattering Three dimensional finite element modeling for passive source electromagnetic sounding method

三维有限孔径逆声散射问题的数值解被动源电磁测深三维有限元数值模拟

So the paper is focused on the investigating measurement method of three-dimensional bottom scattering strength and the properties of irregular sea area reverberation. A method for measured bottom three-dimensional scattering strength is given in the paper which can measure sector scattering area three-dimensional bottom scattering strength.

基于此，本文主要研究海底三维声散射强度的测量方法以及不规则海域的混响特性。

The Analysis of Three-Dimensional Electromagnetic Scattering Problems by Using the Preconditioned Conjugate-Gradient Technique Together with the Finite-Difference Frequency-Domain

有限差分法结合预条件共轭梯度分析三维电磁散射问题

The finite-difference frequency-domain method with preconditioned conjugate-gradient technique is presented for three-dimensional electromagnetic scattering problems.

引入预条件共轭梯度法，提出了结合频域有限差分法分析三维电磁散射问题。

Then the parallel MOM for solving three-dimensional electromagnetic scattering problems is implemented and optimized with smaller particle size.

随后又以更小的粒度实现了基于GPU的三维导体电磁散射问题的并行矩量法加速，并且对程序进行了优化。

Application of Vector OSRC to Three-Dimensional Electromagnetic Scattering

三维电磁散射计算中的矢量表面辐射条件

To explain the phenomena, on the basis of ray-mode reverberation theory and three-dimensional scattering model, the expressions of the bistatic reverberation loss and the vertical correlation are put forward.

为了解释这一现象，根据浅海混响的射线简正波理论，结合三维海底散射模型，给出了浅海异地混响衰减和混响垂直相关的一般表达式。

At last the experiment result and the result using the model of calculating sea bottom three-dimensional scattering strength are compared and analyzed. The result indicated that is matched quite well.

并将实验测量结果与海底三维散射强度计算模型的计算结果进行了对比分析，结果表明，二者有较好的一致性。

The three-dimensional scattering operator formulations with application in the three-dimensional inverse scattering are reviewed with emphasis on the elastic wave case.

以弹性波为重点，评述了三锥散射算子关系及其在逆散射中的应用。

The Application of ADI-FDTD for Three-Dimensional Scattering

ADI-FDTD在三维散射计算中的应用

This dissertation studies the integral equation method and its key techniques for three-dimensional scattering problems in multilayered media.

本文深入研究了求解平面分层介质中三维目标电磁散射的积分方程方法及其关键技术。

High-order FDTD for calculating three-dimensional scattering problems

高阶FDTD方法在三维散射问题中的应用

Measurement and Model Calculation of Sea Bottom Three-dimensional Scattering Strength

海底三维散射强度的测量和模型计算

A three-dimensional high-precision micro-motional scanning stage for the three-dimensional contour scanner is designed and implemented. This paper also introduces the process of the design and implementation of this stage scheme in detail.

设计并研制了一套用于三维轮廓扫描仪的高精度三维扫描微动平台，详细介绍了平台硬件部分的方案设计与搭建过程。

Objective To test the reliability of the three-dimensional dental cast laser scanner for clinical applications.

目的对牙颌模型三维激光扫描系统的可靠性进行研究，并为其临床应用提供科学依据。

The reliability study of three-dimensional dental cast laser scanner and comparison with manual measurement

牙颌模型三维激光扫描系统可靠性研究及与手工测量的比较

Second, three-dimensional hand-held scanner can also be applied in quantitative study of cleft lip ( and palate) patients to evaluate if the measurement is within normal range and the symmetry of both sides, so that the assessment of treatment outcome can be concluded.

而手持式三维扫描仪也可应用在唇（腭）裂术后定量评价中，评价测量值是否处于正常参考值范围内以及左右侧结构是否对称，并由此对手术效果做出判断。

At last, the error model of the three dimensional laser scanner was established. ( 2) The point cloud data which obtained by the three-dimensional laser scanner includes massive mixed spots and the noise will bring a lot of trouble for our later processing and application.

由三维激光扫描仪测量得到的点云数据含有大量的杂点和噪声，为其后续处理与应用带来了很大的麻烦。

According to the problems encountered in the point cloud data organization and management, this thesis mainly studies how to improve the search efficiency and the registration speed by organizing and managing data. Firstly, the point cloud data can be obtained through the three-dimensional laser scanner technology.

本文针对点云数据的组织管理以及数据配准方面遇到的问题，研究如何组织管理数据来提高数据的搜索效率以及配准速度。