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A Deep Learning Method to Process Scattered Field Data in Biomedical Imaging System
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作者 Jing Wang Naike Du Xiuzhu Ye 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期213-218,共6页
This paper proposed a deep-learning-based method to process the scattered field data of transmitting antenna,which is unmeasurable in inverse scattering system because the transmitting and receiving antennas are multi... This paper proposed a deep-learning-based method to process the scattered field data of transmitting antenna,which is unmeasurable in inverse scattering system because the transmitting and receiving antennas are multiplexed.A U-net convolutional neural network(CNN)is used to recover the scattered field data of each transmitting antenna.The numerical results proved that the proposed method can complete the scattered field data at the transmitting antenna which is unable to measure in the actual experiment and can also eliminate the reconstructed error caused by the loss of scattered field data. 展开更多
关键词 inverse problem scattered field deep learning
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Reduction of distortion and improvement of efficiency for gridding of scattered gravity and magnetic data 被引量:1
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作者 张晨 姚长利 +3 位作者 谢永茂 郑元满 关胡良 洪东明 《Applied Geophysics》 SCIE CSCD 2012年第4期378-390,494,共14页
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... 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. 展开更多
关键词 scattered data gridding parameters analysis of distribution features human-machine interaction multi-thread parallel technology
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Numerical simulation scattered imaging in deep mines 被引量:1
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作者 胡明顺 潘冬明 李娟娟 《Applied Geophysics》 SCIE CSCD 2010年第3期272-282,294,共12页
Conventional seismic exploration,mostly based on reflection theory,hardly has accurate imaging results for disaster geologic bodies which have small scale,steep dip,or complex structure.In this paper,we design two typ... Conventional seismic exploration,mostly based on reflection theory,hardly has accurate imaging results for disaster geologic bodies which have small scale,steep dip,or complex structure.In this paper,we design two typical geologic models for analyzing the characteristics of scattered waves in mines for forward modeling by finite difference and apply the equivalent offset migration(EOM)and EOM-based interference stack migration methods to mine prospecting.We focus on the analysis of scatted imaging’s technological superiority to reflection imaging.Research shows:1)scattered imaging can improve fold and make the best of weak scattered information,so it shows better results than post-stack migration imaging and 2)it can utilize the diffraction stack migration method-based ray path theory for mine seismic advanced prediction,so it provides an new efficient imaging method for improving resolution of mine seismic exploration. 展开更多
关键词 MINE seismic exploration scattered wave seismic imaging numerical simulation
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Ultrasonic Scattered Field Distribution of One and Two Cylindrical Solids with Phased Array Technique 被引量:4
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作者 Xiaozhou Liu Jian Ma +3 位作者 Haibin Wang Sha Gao Yifeng Li Jiehui Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第6期101-112,共12页
The scattered fields of plane waves in a solid from a cylinder or sphere are critical in determining its acoustic characteristics as well as in engineering applications. This paper investigates the scattered field dis... The scattered fields of plane waves in a solid from a cylinder or sphere are critical in determining its acoustic characteristics as well as in engineering applications. This paper investigates the scattered field distributions of different incident waves created by elastic cylinders embedded in an elastic isotropic medium. Scattered waves, including longitudinal and transverse waves both inside and outside the cylinder, are described with specific modalities under an incident plane wave. A model with a scatterer embedded in a structural steel matrix and filled with aluminum is developed for comparison with the theoretical solution. The frequency of the plane wave ranged from 235 kHz to 2348 kHz, which corresponds to scaling factors from 0.5 to 5. Scattered field distributions in matrix materials blocked by an elastic cylindrical solid have been obtained by simulation or calculated using existing parameters. The simulation results are in good agreement with the theoretical solution, which supports the correctness of the simulation analysis. Furthermore, ultrasonic phased arrays are used to study scattered fields by changing the characteristics of the incident wave. On this foundation, a partial preliminary study of the scattered field distribution of double cylinders in a solid has been carried out, and the scattered field distribution at a given distance has been found to exhibit particular behaviors at different moments. Further studies on directivities and scattered fields are expected to improve the quantification of scattered images in isotropic solid materials by the phased array technique. 展开更多
关键词 Ultrasonic phased array scattered field distribution DIRECTIVITY Quantification of scattered image
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Intestinal disease of scattered mirror carp Cyprinus carpio caused by Thelohanellus kitauei and notes on the morphology and phylogeny of the myxosporean from Sichuan Province,southwest China 被引量:4
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作者 叶灵通 卢明淼 +5 位作者 权可艳 李文祥 邹红 吴山功 王江勇 王桂堂 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期587-596,共10页
The mass mortality of pond-reared scattered mirror carp, Cyprinus carpio, caused by Thelohanellus kitauei, occurred at fish farms in Sichuan Province, southwest China. Morphological and molecular analyses were supplem... The mass mortality of pond-reared scattered mirror carp, Cyprinus carpio, caused by Thelohanellus kitauei, occurred at fish farms in Sichuan Province, southwest China. Morphological and molecular analyses were supplemented with histological evaluation of infected tissues to better understand the route of infection and the pathological effects of 1". kitauei on the fish host. The intestine of the diseased host was full of large cysts of the myxosporean. The cysts range from 2 cm to 3.6 cm in diameter. Histopathology indicated that T. kitauei first invaded the submucosa of the host intestine and then moved into the mucosa layers with the development of their spores, finally entering into the enteric cavity of the hosts after the disruption of mucosa layers. The pyriform spores of T. kitauei were surrounded by the transparent spore sheath, measuring 25.98/μm±0.95 μm in body length, 8.72 μm±0.51μm body width, and 7.86 μm±0.26 μm in body thickness. The single polar capsule was pyriform, measuring 14.73 μm±0.92μm in length and 6.82 μm±0.45μm in width, with eight to 10 turns of filament coils winding inside. Phylogenetic analysis based on the 18S small-subunit ribosomal DNA sequences indicated that minimal genetic differences were present between T. kitauei samples from South Korea and from China. Close affinity was found between the genus Thelohanellus and Myxobolus. Additionally, two polar capsule nuclei were found at the anterior end of the single polar capsule in spores of T. kitauei stained with hematoxylin and eosin, which suggested the separation of the genus Thelohanellus from Myxobolus. 展开更多
关键词 intestinal disease scattered mirror carp Thelohanellus kitauei host-specific tropism MORPHOLOGY PHYLOGENY
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Energy Filtering and Coaxial Detection of the Backscattered Electrons in Scanning Electron Microscope 被引量:5
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作者 JIANG Chang-Zhong P.Morin N.Rosenberg 《Chinese Physics Letters》 SCIE CAS CSCD 2000年第9期637-639,共3页
A new detection system in scanning electron microscope,which filters in energy and detects the backscattered electrons close to the microscope axis,is described.This technique ameliorates the dependence of the back.sc... A new detection system in scanning electron microscope,which filters in energy and detects the backscattered electrons close to the microscope axis,is described.This technique ameliorates the dependence of the back.scat tering coefficient on atomic number,and suppresses effectively the relief contrast at the same time.Therefore this new method is very suitable to the composition analysis. 展开更多
关键词 ELECTRON scattered SYSTEM
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Scattered Rural Settlements and Development of Mountainous Regions in Western Sichuan,China 被引量:3
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作者 GAO Yanjun CHEN Guojie SHEN Maoying 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期737-742,共6页
Making rural settlements of Mountainous Regions in Western Sichuan as the study objects and using symbolic statistical methods, then combining the case study of Daofu County, the paper analyzes the negative impact of ... Making rural settlements of Mountainous Regions in Western Sichuan as the study objects and using symbolic statistical methods, then combining the case study of Daofu County, the paper analyzes the negative impact of the scattered rural settlements on infrastructure construction, farmers' income increase and mountain ecological reconstruction in mountainous regions of western Sichuan. The results indicate that economic density is positively related to both rural settlements density (R^2=0.73) and rural population density (R^2=0.77), and it is the same for relationship between towns density and rural settlements density (R^2=0.88) and between towns density and economic density (R^2=0.71), and the scattered distribution pattern of the rural settlements and shortage of economic centers is a major factor to the lagged socioeconomic development. On the eco-economic zoning to Daofu County, the paper indicates the spatial distribution model and the industrial development model of the rural settlements need to be changed, and rural population should be concentrated in larger rural settlements with development of off-farm industries while infrastructure construction is to reinforced. 展开更多
关键词 mountainous regions in western Sichuan rural settlement scattered distribution DEVELOPMENT
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HERMITE—BIRKHOFF INTERPOLATION OF SCATTERED DATA BY RADIAL BASIS FUNCTIONS 被引量:6
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作者 吴宗敏 《Analysis in Theory and Applications》 1992年第2期1-10,共10页
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'... 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. 展开更多
关键词 HERMITE BIRKHOFF INTERPOLATION OF scattered DATA BY RADIAL BASIS FUNCTIONS
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A new deep-reading look-ahead method in electromagnetic loggingwhile-drilling using the scattered electric field from magnetic dipole antennas 被引量:1
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作者 Lei Wang Shao-Gui Deng +3 位作者 Guan-Bao Xie Shan-Jun Li Zhen-Guan Wu Yi-Ren Fan 《Petroleum Science》 SCIE CAS CSCD 2022年第1期180-188,共9页
This paper presents a new deep-reading logging-while-drilling electromagnetic(EM)logging method to detect bed boundaries ahead of bit.Unlike all existing EM logging approaches,the new method is based on the scattered ... This paper presents a new deep-reading logging-while-drilling electromagnetic(EM)logging method to detect bed boundaries ahead of bit.Unlike all existing EM logging approaches,the new method is based on the scattered electric field radiated by a magnetic dipole antenna.By analyzing the characteristics of electric tensor responses in layered formations,optimal look-ahead electric component is selected.The selected scattered field contributes to a large portion of the total field and is strongly sensitive to the boundary position.The measured voltage from the scattered electric component can be tens of times larger than that from the scattered magnetic fields and it attenuates slower.Thus,the detection capability improves significantly.A coaxial open-loop half-circle antenna is then proposed to measure the electric field in logging while drilling environment.A practical tool implementation equipped with two tilted close-loop antennas and two open-loop antennas is further developed for look-ahead application.Numerical results demonstrate that the detection depth of the new look-ahead tool can be up to 40 m under favorable conditions.Compared with current look-ahead logging tools,the new method not only significantly shortens the tool size,but also can recognize the boundary position and azimuth. 展开更多
关键词 Electromagnetic logging-while-drilling LOOK-AHEAD Deep reading scattered electric field Short spacing
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Genetic Algorithm for Scattered Storage Assignment in Kiva Mobile Fulfillment System 被引量:4
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作者 Mengcheng Guan Zhenping Li 《American Journal of Operations Research》 2018年第6期474-485,共12页
Scattered storage means an item can be stored in multiple inventory bins. The scattered storage assignment problem based on association rules in Kiva mobile fulfillment system is investigated, which aims to decide the... Scattered storage means an item can be stored in multiple inventory bins. The scattered storage assignment problem based on association rules in Kiva mobile fulfillment system is investigated, which aims to decide the pods for each item to put on so as to minimize the number of pods to be moved when picking a batch of orders. This problem is formulated into an integer programming model. A genetic algorithm is developed to solve the large-sized problems. Computational experiments and comparison between the scattered storage strategy and random storage strategy are conducted to evaluate the performance of the model and algorithm. 展开更多
关键词 scattered Storage ASSIGNMENT KIVA MOBILE Fulfillment SYSTEM Association Rules GENETIC Algorithm
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Surface Reconstruction of 3D Scattered Data with Radial Basis Functions 被引量:1
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作者 Du XIN-WEI YANG XIAO-YING LIANG XUE-ZHANG 《Communications in Mathematical Research》 CSCD 2010年第2期183-192,共10页
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 improveme... 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. 展开更多
关键词 radial basis function scattered data implicit surface surface reconstruction
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Investigation on a Typical Scattered Lightning Strike Case and Response Measures 被引量:1
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作者 Wei Li Guiqiong Zhao Ping Wang 《Meteorological and Environmental Research》 CAS 2013年第7期8-9,14,共3页
From July 31 to August I in 2008, a strong thunderstorm process occurred in Neijiang of Sichuan Province, and a strange scattered light- ning strike phenomenon happened in office building of Dongxing Meteorological Bu... From July 31 to August I in 2008, a strong thunderstorm process occurred in Neijiang of Sichuan Province, and a strange scattered light- ning strike phenomenon happened in office building of Dongxing Meteorological Bureau in Neijiang. Through a series of investigations and analyses, we found occurrence reason of the scattered lightning strike and improved lightning protection measures. 展开更多
关键词 scattered lightning strike High elevated lightning rod Preventive measures China
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Mesh Generation from Dense 3D Scattered Data Using Neural Network 被引量:8
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作者 ZHANGWei JIANGXian-feng +1 位作者 CHENLi-neng MAYa-liang 《Computer Aided Drafting,Design and Manufacturing》 2004年第1期30-35,共6页
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 scatt... 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. 展开更多
关键词 reverse engineering mesh generation neural network scattered points data extraction
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Large Scattered Data Fitting Based on Radial Basis Functions 被引量:2
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作者 FENG Ren-zhong XU Liang 《Computer Aided Drafting,Design and Manufacturing》 2007年第1期66-72,共7页
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 difficult... 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. 展开更多
关键词 scattered data radial basis functions interpolation least squares fitting uniform centers
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Simulations of scattered neutrons for the time-of-flight enhanced diagnostics(TOFED)neutron spectrometer on EAST
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作者 Jiaqi SUN Zhimeng HU +13 位作者 Lijian GE Yimo ZHANG Tengfei DU Xingyu PENG Zhongjing CHEN Xing ZHANG Giuseppe GORINI Massimo NOCENTE Marco TARDOCCHI Liqun HU Guoqiang ZHONG Baonian WAN Xiangqing LI Tieshuan FAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期27-33,共7页
The time-of-flight enhanced diagnostics(TOFED)neutron spectrometer has been installed in TOFED house,which is a newly-built neutron diagnostic lab outside the EAST experimental hall.The line of sight(LOS)of TOFED is d... The time-of-flight enhanced diagnostics(TOFED)neutron spectrometer has been installed in TOFED house,which is a newly-built neutron diagnostic lab outside the EAST experimental hall.The line of sight(LOS)of TOFED is defined by the collimator going through the 150 cm biological shielding wall,which can reduce background neutrons very effectively for the neutron spectral measurements.The Monte Carlo code MCNP5 is used in the simulations to characterize collimation effects and the radiation safety of the new house.The collimator makes neutron flux almost fully perpendicular to S 1 detectors.In addition,the proportion of scattered neutrons in the LOS of the TOFED is obtained for the measured spectral data interpretation.The simulation results show that the TOFED house satisfies the requirement for the TOFED operations at EAST and gives a safe environment for personnel access during the EAST operation. 展开更多
关键词 EAST TOFED scattered components SHIELDING EFFICIENCY
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理想D空间和理想scattered空间在信息系统中的应用
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作者 吴琼淄 刘媛媛 +1 位作者 廖波 卢诗展 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2023年第1期43-48,共6页
通过引入理想D空间概念,研究了理想D空间的空间性质,讨论了理想D空间与理想scattered空间的关系,并通过二者在信息系统中的应用实例进行说明。
关键词 理想D空间 理想scattered空间 导出长度 信息系统
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Doppler shift of a laser pulse beam scattered by a rotating cone and cylinder
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作者 王保平 王明军 +2 位作者 吴振森 李应乐 向宁静 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期60-65,共6页
Based on laser radar equations, a Doppler shift model of a laser pulse beam scattered by a rotating arbitrary convex target is reported in this paper. The boundary relations between an incident pulse beam and the dete... Based on laser radar equations, a Doppler shift model of a laser pulse beam scattered by a rotating arbitrary convex target is reported in this paper. The boundary relations between an incident pulse beam and the detected area elements are analyzed by geometric methods. The Doppler shift characteristics of the rotating cone and cylinder are discussed and the difference between the laser pulse beam and the plane wave scattered from the same rotating target is compared accordingly. Numerical simulations show that the Doppler shift is tightly relevant to their dimensions, speeds, and so on. In the same incidence conditions, the pulse beam and plane wave have difference peak values and the same Doppler shift bandwidth. If the waist radius of the pulse beam is larger, the peak value is higher, and the Doppler shifts are proportional to the speed of the rotating target. By virtue of our theoretical model, we probe into the scattered characteristics of the Doppler shifts of a laser pulse beam, which would benefit target identification in national defense. 展开更多
关键词 scattered characteristics of laser pulse beams Doppler shift laser radar target identification
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Spin Polarization Electrons of Elastically Scattered from Hg Atom
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作者 YUAN Jianmin ZHANG Zhijie 《Chinese Physics Letters》 SCIE CAS CSCD 1992年第9期459-462,共4页
Calculations on differential cross sections and spin polarization parameters of elastical electron scattering with Hg atoms are performed for electrons in the energy range from 0.5 to 150eV.Dirac equation is used to d... Calculations on differential cross sections and spin polarization parameters of elastical electron scattering with Hg atoms are performed for electrons in the energy range from 0.5 to 150eV.Dirac equation is used to describe the motion of scattered electrons in the target field,which includes static,exchange and correlation-polarization interactions.The agreement between theory and experiment is generally good. 展开更多
关键词 POLARIZATION ELECTRON scattered
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C^1 C^2INTERPOLATION OF SCATTERED DATA POINTS 
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作者 WANG JIAYE AND ZHANG CAIMING(Department of Computer Science,Shandong University Jinan 250100) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期1-9,共9页
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 polyno... 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. 展开更多
关键词 INTERPOLATION scattered Data Points TRIANGLE POLYNOMIAL BarycentricCoordinate.
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Thin-film approximate point scattered function and its application to neutron radiography
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作者 Jun Qin Jia-Yu Ni +2 位作者 Lin-Feng Ye De-Hong Gao Wei-Jun Jiang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第9期1-9,共9页
A simpler and improved utility approximate point scattered function for thin-film converters currently used in neutron photographic devices is proposed as a correction method to produce clearer,more realistic images.T... A simpler and improved utility approximate point scattered function for thin-film converters currently used in neutron photographic devices is proposed as a correction method to produce clearer,more realistic images.The validity of the model was demonstrated through a simulation experiment.Based on the results,an error analysis was carried out,certain corrections were made to the original model,and the final model achieved a very low relative error in the simulation experiment.The model can also be optimized for quantitative neutron photographic analysis using iterative algorithms to obtain realistic neutron photographic images more quickly.At the end of the article,the model is extended to consider the case of energy spectrum hardening by introducing a temperature correction parameter. 展开更多
关键词 Neutron radiography Point scattered function Image processing
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