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Structure-oriented edge-preserving smoothing based on accurate estimation of orientation and edges 被引量:1
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作者 王珺 陈雨红 乔玉雷 《Applied Geophysics》 SCIE CSCD 2009年第4期367-376,395,共11页
In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orie... In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orientation and edge of the reflections. The information is usually estimated from seismic data with full frequency bandwidth. When the data has a very low signal to noise ratio (SNR), the noise usually reduces the estimation accuracy. For seismic data with extremely low SNR, the dominant frequency has higher SNR than other frequencies, so it can provide orientation and edge information more reliably than other frequencies. Orientation and edge are usually described in terms of apparent reflection dips and coherence differences, respectively. When frequency changes, both dip and coherence difference change more slowly than the seismogram itself. For this reason, dip and coherence estimated from dominant frequency data can approximately represent those of other frequency data. Ricker wavelet are widely used in seismic modeling. The Marr wavelet has the same shape as Ricker wavelets in both time and frequency domains, so the Marr wavelet transform is selected to divide seismic data into several frequency bands. Reflection apparent dip as well as the edge information can be obtained by scanning the dominant frequency data. This information can be used to selectively smooth the frequency bands (dominant, low, and high frequencies) separately by structure-oriented edge-preserving smoothing technology. The ultimate noise-suppressed seismic data is the combination of the smoothed frequency band data. Application to synthetic and real data shows the method can effectively reduce noise, preserve edges, improve trackable reflection continuity, and maintain useful information in seismic data. 展开更多
关键词 ORIENTATION EDGE dominant frequency wavelet transform structure-oriented edge-preserving smoothing
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Sizing of Energy Storage Systems for Output Smoothing of Renewable Energy Systems 被引量:131
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作者 王成山 于波 +1 位作者 肖峻 郭力 《中国电机工程学报》 EI CSCD 北大核心 2012年第16期I0001-I0026,共26页
光伏、风力发电等可再生能源(renewable energysources,RESs)具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响,提出了用于平滑RESs发电系统功率输出的储能系统(energy storage system,ESS)容量优化确定方法。... 光伏、风力发电等可再生能源(renewable energysources,RESs)具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响,提出了用于平滑RESs发电系统功率输出的储能系统(energy storage system,ESS)容量优化确定方法。利用离散傅里叶变换(discrete Fouriertransform,DFT)对RESs输出功率进行频谱分析,基于频谱分析结果,考虑ESS充放电效率、荷电状态(stateofcharge,soc)及RESs发电系统目标功率输出波动率的约束,确定所需ESS最小容量。采用美国华盛顿州实际观测风速数据及日本东北电力公司风电场接入电网20rnin有功功率波动规范(最大波动率为10%),在一风力发电系统中对该方法进行了验证。算例结果表明采用该方法能够以较小的容量将风机输出最大波动率由61.7%降到9.9%。 展开更多
关键词 可再生能源 输出能量 存储系统 能源系统 平滑 RESS 选型 随机波动
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Study on the Planning of Cluster-based Scenic Areas with Jingyanggang Scenic Area as an Example
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作者 翟付顺 于守超 +1 位作者 张秀省 李文静 《Journal of Landscape Research》 2010年第3期9-12,共4页
Cluster-based scenic area is a special form within the scenic area system, scenic areas are always scattered with diversified landscape resources, thus planning should be made according to actual conditions of the loc... Cluster-based scenic area is a special form within the scenic area system, scenic areas are always scattered with diversified landscape resources, thus planning should be made according to actual conditions of the local area, and pertinent measures should be applied. Through elaborating the detail work in the overall planning of Jingyanggang Scenic Area, such as landscape division, spatial layout and sightseeing structure, the authors discussed several problems should be paid more attention in the planning of cluster-based scenic areas. 展开更多
关键词 cluster-based scenic areas PLANNING Jingyanggang
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SMOOTHING NEWTON ALGORITHM FOR THE CIRCULAR CONE PROGRAMMING WITH A NONMONOTONE LINE SEARCH 被引量:8
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作者 迟晓妮 韦洪锦 +1 位作者 万仲平 朱志斌 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1262-1280,共19页
In this paper, we present a nonmonotone smoothing Newton algorithm for solving the circular cone programming(CCP) problem in which a linear function is minimized or maximized over the intersection of an affine space w... In this paper, we present a nonmonotone smoothing Newton algorithm for solving the circular cone programming(CCP) problem in which a linear function is minimized or maximized over the intersection of an affine space with the circular cone. Based on the relationship between the circular cone and the second-order cone(SOC), we reformulate the CCP problem as the second-order cone problem(SOCP). By extending the nonmonotone line search for unconstrained optimization to the CCP, a nonmonotone smoothing Newton method is proposed for solving the CCP. Under suitable assumptions, the proposed algorithm is shown to be globally and locally quadratically convergent. Some preliminary numerical results indicate the effectiveness of the proposed algorithm for solving the CCP. 展开更多
关键词 circular cone programming second-order cone programming nonmonotone line search smoothing Newton method local quadratic convergence
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EFFICIENT ESTIMATION OF FUNCTIONAL-COEFFICIENT REGRESSION MODELS WITH DIFFERENT SMOOTHING VARIABLES 被引量:5
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作者 张日权 李国英 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期989-997,共9页
In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the l... In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the local linear technique and the averaged method,the initial estimates of the coefficient functions are given.Second step,based on the initial estimates,the efficient estimates of the coefficient functions are proposed by a one-step back-fitting procedure.The efficient estimators share the same asymptotic normalities as the local linear estimators for the functional-coefficient models with a single smoothing variable in different functions.Two simulated examples show that the procedure is effective. 展开更多
关键词 Asymptotic normality averaged method different smoothing variables functional-coefficient regression models local linear method one-step back-fitting procedure
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An Empirical Study of Good-Turing Smoothing for Language Models on Different Size Corpora of Chinese 被引量:5
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作者 Feng-Long Huang Ming-Shing Yu Chien-Yo Hwang 《Journal of Computer and Communications》 2013年第5期14-19,共6页
Data sparseness has been an inherited issue of statistical language models and smoothing method is usually used to resolve the zero count problems. In this paper, we studied empirically and analyzed the well-known smo... Data sparseness has been an inherited issue of statistical language models and smoothing method is usually used to resolve the zero count problems. In this paper, we studied empirically and analyzed the well-known smoothing methods of Good-Turing and advanced Good-Turing for language models on large sizes Chinese corpus. In the paper, ten models are generated sequentially on various size of corpus, from 30 M to 300 M Chinese words of CGW corpus. In our experiments, the smoothing methods;Good-Turing and Advanced Good-Turing smoothing are evaluated on inside testing and outside testing. Based on experiments results, we analyzed further the trends of perplexity of smoothing methods, which are useful for employing the effective smoothing methods to alleviate the issue of data sparseness on various sizes of language models. Finally, some helpful observations are described in detail. 展开更多
关键词 Good-Turing Methods smoothing LANGUAGE Models PERPLEXITY
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Mesh Smoothing Method Based on Local Wave Analysis 被引量:2
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作者 QIN Xujia ZHENG Hongbo +2 位作者 CHENG Shiwei LIU Shishuang XU Xiaogang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期598-607,共10页
As the mesh models usually contain noise data,it is necessary to eliminate the noises and smooth the mesh.But existed methods always lose geometric features during the smoothing process.Hence,the noise is considered a... As the mesh models usually contain noise data,it is necessary to eliminate the noises and smooth the mesh.But existed methods always lose geometric features during the smoothing process.Hence,the noise is considered as a kind of random signal with high frequency,and then the mesh model smoothing is operated with signal processing theory.Local wave analysis is used to deal with geometric signal,and then a novel mesh smoothing method based on the local wave is proposed.The proposed method includes following steps:Firstly,analyze the principle of local wave decomposition for 1D signal,and expand it to 2D signal and 3D spherical surface signal processing;Secondly,map the mesh to the spherical surface with parameterization,resample the spherical mesh and decompose the spherical signals by local wave analysis;Thirdly,propose the coordinate smoothing and radical radius smoothing methods,the former filters the mesh points' coordinates by local wave,and the latter filters the radical radius from their geometric center to mesh points by local wave;Finally,remove the high-frequency component of spherical signal,and obtain the smooth mesh model with inversely mapping from the spherical signal.Several mesh models with Gaussian noise are processed by local wave based method and other compared methods.The results show that local wave based method can obtain better smoothing performance,and reserve more original geometric features at the same time. 展开更多
关键词 mesh models local wave analysis noise smoothing
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Temporal Floorplanning Using Solution Space Smoothing Based on 3D-BSSG Structure
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作者 郑舒一 董社勤 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第10期1916-1924,共9页
We develop a 3D bounded slice-surface grid (3D-BSSG) structure for representation and introduce the solution space smoothing technique to search for the optimal solution. Experiment results demonstrate that a 3D-BSS... We develop a 3D bounded slice-surface grid (3D-BSSG) structure for representation and introduce the solution space smoothing technique to search for the optimal solution. Experiment results demonstrate that a 3D-BSSG structure based algorithm is very effective and efficient. 展开更多
关键词 temporal floorplanning~ FPGA 3D-BSSG solution space smoothing
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ANALYTICAL SMOOTHING EFFECT OF SOLUTION FOR THE BOUSSINESQ EQUATIONS 被引量:1
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作者 Feng CHENG Chao jiang XU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期165-179,共15页
In this article, we study the analytical smoothing effect of Cauchy problem for the incompressible Boussinesq equations. Precisely, we use the Fourier method to prove that the Sobolev H^1 -solution to the incompressib... In this article, we study the analytical smoothing effect of Cauchy problem for the incompressible Boussinesq equations. Precisely, we use the Fourier method to prove that the Sobolev H^1 -solution to the incompressible Boussinesq equations in periodic domain is analytic for any positive time. So the incompressible Boussinesq equations admit exactly same smoothing effect properties of incompressible Navier-Stokes equations. 展开更多
关键词 ANALYTICITY smoothing effect of SOLUTIONS BOUSSINESQ EQUATION
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Effective search with saliency-based matching and cluster-based browsing 被引量:4
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作者 张晓宇 《High Technology Letters》 EI CAS 2013年第1期105-109,共5页
Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies... Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies on human perception, and major emphasis on the saliently similar aspect of objects to be compared is placed and thus the search result is more agreeable for users. After relevant results are obtained, the cluster-based browsing algorithm is adopted for search result presentation based on social network analysis. By organizing the results in clustered lists, the user can have a general understanding of the whole collection by viewing only a small part of results and locate those of major interest rapidly. Experimental results demonstrate the advantages of the proposed algorithm over the traditional work. 展开更多
关键词 information retrieval saliency-based matching human perception cluster-based browsing social network
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ANALYSIS ON CODE MULTIPATH MITIGATION BY PHASE-AIDED SMOOTHING 被引量:1
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作者 Xia Linyuan Liu Jingnan +1 位作者 Zhang Songbo Deng Yuejin 《Geo-Spatial Information Science》 1999年第1期73-77,共5页
Multipath influence on code range under static condition is described firstly in this paper, and the problem that to what extent the phase-aided smoothing can mitigate multipath interference is detailed. Some problems... Multipath influence on code range under static condition is described firstly in this paper, and the problem that to what extent the phase-aided smoothing can mitigate multipath interference is detailed. Some problems regarding smoothing and mitigation are discussed. Suggestions based on the analysis has been made. 展开更多
关键词 MULTIPATH MULTIPATH MITIGATION smoothing
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Capacity Research in Cluster-Based Underwater Wireless Sensor Networks Based on Stochastic Geometry 被引量:2
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作者 Xia Li Dongxue Zhao 《China Communications》 SCIE CSCD 2017年第6期80-87,共8页
Underwater wireless sensor networks(UWSNs) have attracted wide attention in recent years.The capacity research on it is still in the initial stage,lacking adequate performance evaluation for network construction.This ... Underwater wireless sensor networks(UWSNs) have attracted wide attention in recent years.The capacity research on it is still in the initial stage,lacking adequate performance evaluation for network construction.This paper will focus on this subject by theoretical analysis and simulation,aiming to provide some insights for the actual UWSNs construction.According to the structure features of cluster-based UWSNs and the propagation characteristics of underwater acoustic signal,with the combination of signal to interference plus noise ratio,we define some capacity performance metrics,such as outage probability and transmission capacity.Based on the theory of stochastic geometry,a network capacity analytical model used in the cluster-based UWSNs is presented.The simulation results verify the validity of the theoretical analysis,and the cause of error between theoretical and simulation results has also been clearly explained. 展开更多
关键词 underwater wireless sensor networks cluster-based transmission capacity stochastic geometry
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EXTENSION OF SMOOTHING FUNCTIONS TO SYMMETRIC CONE COMPLEMENTARITY PROBLEMS 被引量:2
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作者 Liu Yongjin Zhang Liwei Liu Meijiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第2期245-252,共8页
The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity proble... The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity problems. Computable formulas for these functions and their Jacobians are derived. In addition, it is shown that these functions are Lipschitz continuous with respect to parameter # and continuously differentiable on J × J for any μ 〉 0. 展开更多
关键词 symmetric cone complementarity problem smoothing function Euclidean Jordan algebra non-interior continuation method
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A novel coordinated control strategy considering power smoothing for a hybrid photovoltaic/battery energy storage system 被引量:6
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作者 DAUD Muhamad Zalani MOHAMED Azah HANNAN M A 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期394-404,共11页
This work presents a novel coordinated control strategy of a hybrid photovoltaic/battery energy storage(PV/BES) system. Different controller operation modes are simulated considering normal, high fluctuation and emerg... This work presents a novel coordinated control strategy of a hybrid photovoltaic/battery energy storage(PV/BES) system. Different controller operation modes are simulated considering normal, high fluctuation and emergency conditions. When the system is grid-connected, BES regulates the fluctuated power output which ensures smooth net injected power from the PV/BES system. In islanded operation, BES system is transferred to single master operation during which the frequency and voltage of the islanded microgrid are regulated at the desired level. PSCAD/EMTDC simulation validates the proposed method and obtained favorable results on power set-point tracking strategies with very small deviations of net output power compared to the power set-point. The state-of-charge regulation scheme also very effective with SOC has been regulated between 32% and 79% range. 展开更多
关键词 photovoltaic power smoothing battery energy storage state-of-charge control islanded microgrid
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HAZARD REGRESSION WITH PENALIZED SPLINE:THE SMOOTHING PARAMETER CHOICE AND ASYMPTOTICS 被引量:1
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作者 童行伟 胡涛 崔恒建 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1759-1768,共10页
In this article, we use penalized spline to estimate the hazard function from a set of censored failure time data. A new approach to estimate the amount of smoothing is provided. Under regularity conditions we establi... In this article, we use penalized spline to estimate the hazard function from a set of censored failure time data. A new approach to estimate the amount of smoothing is provided. Under regularity conditions we establish the consistency and the asymptotic normality of the penalized likelihood estimators. Numerical studies and an example are conducted to evaluate the performances of the new procedure. 展开更多
关键词 proportional hazards penalized spline smoothing parameter choice asymptotic normality
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A Study on Precipitation Products with High Resolution in Anhui Province Based on Thin Plate Smoothing Spline 被引量:1
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作者 Li Jun Wen Huayang Chen Fengjiao 《Meteorological and Environmental Research》 CAS 2019年第3期41-47,共7页
In order to achieve refined precipitation grid data with high accuracy and high spatial resolution,hourly precipitation grid dataset with 1 km spatial resolution in Anhui Province from May to September (in the rainy s... In order to achieve refined precipitation grid data with high accuracy and high spatial resolution,hourly precipitation grid dataset with 1 km spatial resolution in Anhui Province from May to September (in the rainy season) in 2016 and from August 2017 to July 2018 was established based on thin plate smoothing spline (TPS),which meets the needs of climate change research and meteorological disaster risk assessment.The interpolation errors were then analyzed.The grid precipitation product obtained based on thin plate smoothing spline,CLDAS-FAST and CLDAS-FRT were evaluated.The results show that the interpolated values of hourly precipitation by thin plate smoothing spline are close to the observed values in the rainy season of 2016.The errors are generally below 0.9 mm/h.However,the errors of precipitation in the mountainous areas of eastern Huaibei and western Anhui are above 1.2 mm/h.On monthly scale,the errors in June and July are the largest,and the proportion of absolute values of the errors ≥2 mm/h is up to 2.0% in June and 2.2% in July.The errors in September are the smallest,and the proportion of absolute values of the errors ≥2 mm/h is only 0.6%.The root mean square (RMSE) is only 0.37 mm/h,and the correlation coefficient (COR) is 0.93.The interpolation accuracy of CLDAS-FRT is the highest,with the smallest RMSE (0.65 mm/h) and mean error ( ME =0.01 mm/h),and the largest COR (0.81).The accuracy of the precipitation product obtained by thin plate smoothing spline interpolation is close to that of CLDAS-FAST.Its RMSE is up to 0.80 mm/h,and its ME is only -0.01 mm/h.Its COR is 0.73,but its bias (BIAS) is up to 1.06 mm/h. 展开更多
关键词 PRECIPITATION High RESOLUTION THIN plate smoothing SPLINE
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MODE SPACE SMOOTHING ALGORITHM TO ESTIMATE DOA OF COHERENT SIGNALS IMPINGING ON UNIFORM CIRCULAR ARRAY 被引量:1
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作者 Ma Changlin Peng Yingning Tian Lisheng Liu Jianhua(Department of Electronic Engineering, Tsinghua University, Beijing 100084) 《Journal of Electronics(China)》 1998年第4期289-295,共7页
A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transfo... A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transforming the UCA from element space to phase mode space to obtain the properties of ordinary ULA, and then the well known spatial smoothing technique is applied to the VULA so that the lost rank of covariance matrix due to signal coherence can be retrieved. This method makes it feasible to use the simple MUSIC algorithm to estimate DOA of coherent signals impinging on a UCA without heavy computation burden. Simulation results strongly verify the effectiveness of the algorithm. 展开更多
关键词 MODE SPACE Virtual uniform linear array Spatial smoothing
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A Smoothing Neural Network Algorithm for Absolute Value Equations 被引量:4
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作者 Feiran Wang Zhensheng Yu Chang Gao 《Engineering(科研)》 2015年第9期567-576,共10页
In this paper, we give a smoothing neural network algorithm for absolute value equations (AVE). By using smoothing function, we reformulate the AVE as a differentiable unconstrained optimization and we establish a ste... In this paper, we give a smoothing neural network algorithm for absolute value equations (AVE). By using smoothing function, we reformulate the AVE as a differentiable unconstrained optimization and we establish a steep descent method to solve it. We prove the stability and the equilibrium state of the neural network to be a solution of the AVE. The numerical tests show the efficient of the proposed algorithm. 展开更多
关键词 ABSOLUTE VALUE EQUATIONS NEURAL Network smoothing FUNCTION Linear Complementarity Problem
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The most homogeneous dip-scanning method using edgepreserving smoothing for seismic noise attenuation 被引量:4
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作者 An Yong Wei Lichun Yang Changchun 《Applied Geophysics》 SCIE CSCD 2006年第4期210-217,共8页
Highlighting and analyzing the geological features of faults and fractures in seismic data is particularly important for hydrocarbon exploration and exploitation since they are often essential for finding and delineat... Highlighting and analyzing the geological features of faults and fractures in seismic data is particularly important for hydrocarbon exploration and exploitation since they are often essential for finding and delineating reservoirs. We apply edge-preserving smoothing (EPS) to seismic processing and propose a most homogeneous dip-scanning method. The method preserves the geological features, eliminate random noise efficiently, obtain dip information, and improve the accuracy of identifying the oil and gas traps. 展开更多
关键词 Dip-scanning most homogeneous edge preserving smoothing signal to noise ratio.
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Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector 被引量:1
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作者 Jian-Feng He Fang Fang +2 位作者 Yao-Zong Yang Yue-Shun He Bin Tang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期7-11,共5页
The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothi... The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM( Peak High/Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall. 展开更多
关键词 T-spectrum data-processing smoothing denoising method comparison and evaluation matlabprogramming
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