Reduction of distortion and improvement of efficiency for gridding of scattered gravity and magnetic data

This paper presents a reasonable gridding-parameters extraction method for setting the optimal interpolation nodes in the gridding of scattered observed data. The method can extract optimized gridding parameters based on the distribution of features in raw data. Modeling analysis proves that distortion caused by gridding can be greatly reduced when using such parameters. We also present some improved technical measures that use human- machine interaction and multi-thread parallel technology to solve inadequacies in traditional gridding software. On the basis of these methods, we have developed software that can be used to grid scattered data using a graphic interface. Finally, a comparison of different gridding parameters on field magnetic data from Ji Lin Province, North China demonstrates the superiority of the proposed method in eliminating the distortions and enhancing gridding efficiency.

HERMITE—BIRKHOFF INTERPOLATION OF SCATTERED DATA BY RADIAL BASIS FUNCTIONS

For Hermite-Birkhoff interpolation of scattered multidumensional data by radial basis function (?),existence and characterization theorems and a variational principle are proved. Examples include (?)(r)=r^b,Duchon's thin-plate splines,Hardy's multiquadrics,and inverse multiquadrics.

Surface Reconstruction of 3D Scattered Data with Radial Basis Functions

We use Radial Basis Functions （RBFs） to reconstruct smooth surfaces from 3D scattered data. An object＇s surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improvements on the methods of surface reconstruction with radial basis functions. A sparse approximation set of scattered data is constructed by reducing the number of interpolating points on the surface. We present an adaptive method for finding the off-surface normal points. The order of the equation decreases greatly as the number of the off-surface constraints reduces gradually. Experimental results are provided to illustrate that the proposed method is robust and may draw beautiful graphics.

Large Scattered Data Fitting Based on Radial Basis Functions

Solving large radial basis function （RBF） interpolation problem with non-customized methods is computationally expensive and the matrices that occur are typically badly conditioned. In order to avoid these difficulties, we present a fitting based on radial basis functions satisfying side conditions by least squares, although compared with interpolation the method loses some accuracy, it reduces the computational cost largely. Since the fitting accuracy and the non-singularity of coefficient matrix in normal equation are relevant to the uniformity of chosen centers of the fitted RBE we present a choice method of uniform centers. Numerical results confirm the fitting efficiency.

Mesh Generation from Dense 3D Scattered Data Using Neural Network

An improved self-organizing feature map (SOFM) neural network is presented to generate rectangular and hexagonal lattic with normal vector attached to each vertex. After the neural network was trained, the whole scattered data were divided into sub-regions where classified core were represented by the weight vectors of neurons at the output layer of neural network. The weight vectors of the neurons were used to approximate the dense 3-D scattered points, so the dense scattered points could be reduced to a reasonable scale, while the topological feature of the whole scattered points were remained.

Geometric Scaling Analysis of Deep Inelastic Scattering Data Including Heavy Quarks

An analytic massive total cross section of photon proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive structure function F2 measured in lepton-hadron scattering experiments at small values of Bjorken x. It is shown that the descriptions of the inclusive structure function F2 and longitudinal structure function FL are improved with the massive analytic structure function, which may imply the gluon saturation effect dominating the parton evolution process at HERA. The inclusion of the heavy quarks prevent the divergence of the lepton-hadron cross section, which plays a significant role in the description of the photoproduction region.

Analysis of the Diffractive Deep Inelastic Scattering Data with Running Coupling and Gluon Number Fluctuations

We study the effects of running coupling and gluon number fluctuations in the latest diffractive deep inelastic scattering data. It is found that the description of the data is improved once the running coupling and gluon number fluctuations are included with x2/d.o.f. = 0.867, x2/d.o.f. = 0.923 and x2/d.o.f. = 0.878 for three different groups of experimental data. The values of diffusive coefficient subtracted from the fit are smaller than the ones obtained by considering only the gluon number fluctuations in our previous studies. The smaller values of the diffusive coefficient are in agreement with the theoretical predictions, where the gluon number fluctuations are suppressed by the running coupling which leads to smaller values of the diffusive coefficient.

Trivariate Polynomial Natural Spline for 3D Scattered Data Hermit Interpolation

Consider a kind of Hermit interpolation for scattered data of 3D by trivariate polynomial natural spline, such that the objective energy functional （with natural boundary conditions） is minimal. By the spline function methods in Hilbert space and variational theory of splines, the characters of the interpolation solution and how to construct it are studied. One can easily find that the interpolation solution is a trivariate polynomial natural spline. Its expression is simple and the coefficients can be decided by a linear system. Some numerical examples are presented to demonstrate our methods.

C^1 C^2INTERPOLATION OF SCATTERED DATA POINTS

In this paper an error in[4]is pointed out and a method for constructingsurface interpolating scattered data points is presented.The main feature of the methodin this paper is that the surface so constructed is polynomial,which makes the construction simple and the calculation easy.

Scattered Data Interpolation Using Cubic Trigonometric Bézier

This paper discusses scattered data interpolation using cubic trigonometric Bézier triangular patches with C1 continuity everywhere.We derive the C1 condition on each adjacent triangle.On each triangular patch,we employ convex combination method between three local schemes.The final interpolant with the rational corrected scheme is suitable for regular and irregular scattered data sets.We tested the proposed scheme with 36,65,and 100 data points for some well-known test functions.The scheme is also applied to interpolate the data for the electric potential.We compared the performance between our proposed method and existing scattered data interpolation schemes such as Powell–Sabin(PS)and Clough–Tocher(CT)by measuring the maximum error,root mean square error(RMSE)and coefficient of determination(R^(2)).From the results obtained,our proposed method is competent with cubic Bézier,cubic Ball,PS and CT triangles splitting schemes to interpolate scattered data surface.This is very significant since PS and CT requires that each triangle be splitting into several micro triangles.

A new package:MySAS for small angle scattering data analysis

In this paper,A MySAS package,which is verified on Windows XP,can easily convert two-dimensional data in small angle neutron and X-ray scattering analysis,operate individually and execute one particular operation as numerical data reduction or analysis,and graphical visualization.This MySAS package can implement the input and output routines via scanning certain properties,thus recalling completely sets of repetition input and selecting the input files.On starting from the two-dimensional files,the MySAS package can correct the anisotropic or isotropic data for physical interpretation and select the relevant pixels.Over 50 model functions are fitted by the POWELL code using x^2 as the figure of merit function.

Geometric Feature Extraction and Model Reconstruction Based on Scattered Data

A method of 3D model reconstruction based on scattered point data in reverse engineering is presented here. The topological relationship of scattered points was established firstly, then the data set was triangulated to reconstruct the mesh surface model. The curvatures of cloud data were calculated based on the mesh surface, and the point data were segmented by edge-based method; Every patch of data was fitted by quadric surface of freeform surface, and the type of quadric surface was decided by parameters automatically, at last the whole CAD model was created. An example of mouse model was employed to confirm the effect of the algorithm.

Hermite interpolation of scattered data based on the assistant surface

An assistant surface was constructed on the base of boundary that being auto-matically extracted from the scattered data.The parameters of every data point corre-sponding to the assistant surface and their applied fields were calculated respectively.Inevery applied region,a surface patch was constructed by a special Hermite interpolation.The final surface can be obtained by a piecewise bicubic Hermite interpolation in the ag-gregate of applied regions of metrical data.This method avoids the triangulation problem.Numerical results indicate that it is efficient and accurate.

Data Processing and Acquisition System for the HT-7 Multipulse Thomson Scattering Diagnostic

This article describes the data processing and acquisition system for the HT-7 mul-tipulse Thomson scattering diagnostic. An eight-pulse laser is used in the Thomson scattering system to obtain electron temperature profiles at eight different times throughout an entire plasma discharge. The major components of the diagnostic system consist of a multipulse Nd-glass laser, a photodetector's subsystem, a calibration set and a CAMAC data processing and acquisition system. The data processing software along with LeCroy 2250L will perform the data acquisition. In order to simplify the operation and extend the capability of its compatibility with other math softwares, the processing software has been improved by the authors. The new software based on the VC++ easily utilizes some math softwares to calculate the electron temperature. The new software is simpler and more operational than the old one.

Minimum Data Sampling Method in the Inverse Scattering Problem

Fourier transform is a basis of the analysis. This paper presents a kind ofmethod of minimum sampling data determined profile of the inverted object ininverse scattering.

空中目标动态电磁散射数据仿真系统设计与实现

电磁散射数据是目标识别研究的基础,但由于试验测量成本高、可重复性差等问题,空中目标电磁散射实测数据十分有限。基于去遮挡的N点模型和电磁计算数据插值研究了空中目标动态电磁散射数据仿真方法,设计了空中目标动态电磁数据仿真系统,该系统将电磁散射仿真与实际飞行场景相结合,支持场景自定义和空中目标三维模型库扩展。分析了飞机和巡航导弹2类目标仿真数据及成像结果,结果验证了仿真方法正确性和系统有效性,可为研究实际场景下的空中目标识别提供支撑。

用于不平衡类癌症数据的非标记检测和识别的SERS分析新策略

SERS技术与机器学习结合的策略在检测和识别不平衡类癌症中发挥着极其重要的作用.为了解决类不平衡问题给分类精度造成的影响,设计了一种SERS技术结合APS-SMOTE-PCA-KNN(synthetic minority oversampling method with adaptive priority selection(APS-SMOTE)-principal component analysis(PCA)-k-nearest neighbors(KNN))的癌症诊断新策略,实现快速、灵敏、非标记地检测和识别癌症.结果显示:新策略能够测得健康人和癌症患者血清的特征光谱,很好地解决了类不平衡问题给分类精度造成的影响,准确率可以达到85.0%.SERS技术结合APS-SMOTE-PCA-KNN对于未来癌症诊断具有积极的借鉴意义.

面向通感一体系统的耐弯三芯光纤

为了同时兼顾狭小空间下的光纤数据通信与环境感知,设计并制备了一种面向通感一体系统的耐弯三芯光纤。该光纤采用三角形纤芯排布和深掺氟折射率沟道结构,标准外径为125μm,优化了O波段(1260~1360 nm)的传输特性,具有与G.657.A1光纤相似的布里渊增益谱(BGS)分布。测试结果表明:在1310 nm波长处,芯层的平均损耗为0.58 dB/km,平均芯间串扰低于-50 dB/km;当最小弯曲半径R=10 mm且缠绕50圈时,光纤的弯曲损耗低于0.1 dB。

基于自抗扰控制的散乱数据随机插补优化模型

随机扰动使得网络数据分布散乱,令散乱数据随机插补精准度下降,构建了基于自抗扰控制的散乱数据随机插补优化模型。使用径向基函数对散乱数据进行逼近,实现散乱数据降噪。构建基于自抗扰控制的随机插补优化模型,即通过定义跟踪微分方程组对散乱数据进行过滤处理。通过跟踪微分算法将被扰动数据替换为稳定跟踪数据。在内部扰动和外部扰动随机插补控制量中引入补偿因子,通过非线性函数来生成随机插补控制量,实现散乱数据随机插补优化。实验结果表明,该模型所有插补数据均与实际数据一致,插补结果更为精准,具备较高的实际应用价值。

声源和障碍物联合反演问题研究

针对声源和障碍物联合反演问题,提出一种并行神经网络方法,同时重建声源的位置和障碍物的位置、形状参数。首先,将远场数据作为并行神经网络的输入序列,声源和障碍物的相关参数作为并行神经网络的输出序列;其次,构建一个特征提取模块,该模块包括GRU模块和Res模块,分别用于提取远场数据的相对位置特征和绝对位置特征;最后,将相对位置特征和绝对位置特征进行融合,通过参数反演模块将融合的特征数据与声源和障碍物的相关参数建立映射关系。数值实验表明了该方法的有效性。