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The Similarity Transformation of Regularizing Functionals and Simularity Property of Their Fourier Transformations
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期105+99-105,共8页
Let and denote respectively the functionswhere λ≥1, The author discusses the similarity transformation of the regularizing functionals of these functions and the similar property of their Fourier transformation.
关键词 Fourier transform generalized functions/similarity transformation regularizing functionals
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Discrepancy and Applicability of Various Similarity Functions in Flux Calculations Under Stable Conditions 被引量:1
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作者 郭晓峰 张宏升 +3 位作者 蔡旭晖 康凌 李万彪 杜金林 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期644-654,共11页
Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxe... Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxes among six sets of similarity functions with the aerodynamic method. It also aims to clarify the applicability of the functions under stable conditions. The relative discrepancy was studied with the normalized transfer coefficients for τ0, H0 and E0, namely CD, CH and CQ, respectively. Except for one set of functions that adopted a rather small von Kármán's constant (0.365), the relative discrepancy in τ0 among the other functions was less than 10%, while that in H0(E0) sometimes reached 25% when the bulk Richardson number (R/B) was less than 0.07. The absolute discrepancy in the fluxes was studied with statistical computations. Among the six sets of functions, the discrepancy in τ0, H0 and E0 sometimes reached 0.03 kg m^-1 s^-2, 4 W m^-2 and 10 W m^-2, respectively, and the discrepancy in the energy balance ratio sometimes exceeded 0.1. Furthermore, when RiB exceeded the critical value (Ric) for a specific set of functions, no fluxes could be derived with the functions. It is therefore suggested that RiB be compared with Ric before computing the fluxes if RiB is less than Ric. Finally, two sets of nonlinear similarity functions are recommended, due to their unlimited applicability in terms of RiB. 展开更多
关键词 aerodynamic method turbulent flux surface layer similarity function energy balance
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IMPROVEMENT TO THE EVAPORATION DUCT MODEL BY INTRODUCING NONLINEAR SIMILARITY FUNCTIONS IN STABLE CONDITIONS 被引量:1
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作者 丁菊丽 费建芳 +2 位作者 黄小刚 胡晓华 周鑫 《Journal of Tropical Meteorology》 SCIE 2011年第1期64-72,共9页
Modified refractivity (M) profile is an important parameter to describe the atmospheric refraction environment,as well as a key factor in uniquely evaluating electromagnetic propagation effects.In order to improve the... Modified refractivity (M) profile is an important parameter to describe the atmospheric refraction environment,as well as a key factor in uniquely evaluating electromagnetic propagation effects.In order to improve the model-derived M profile in stable (especially very stable) conditions,three nonlinear similarity functions,namely BH91,CB05,SHEBA07,are introduced in this paper to improve the original Babin_V25 model,and the performances of these modified models are verified based on the hydrometeorological observations from tower platforms,which are finally compared with the original Babin_V25 model and Local_HYQ92 model.Results show that introducing nonlinear similarity functions can significantly improve the model-derived M profile;especially,the newly developed SHEBA07 functions manage to reduce the predicted root mean square (rms) differences of M and M slope (for both 0-5m and 5-40m) by 64.5%,16.6%,and 60.4%,respectively in stable conditions.Unfortunately,this improved method reacts little on the evaporation duct height;in contrast,Local_HYQ92 model is capable of reducing the predicted rms differences of M,M slope (for both 0-5m and 5-40m),and evaporation duct height by 76.7%,40.2%,83.7%,and 58.0% respectively.Finally,a new recommendation is made to apply Local_HYQ92 and Babin_SHEBA07 in very stable conditions considering that M slope is more important than evaporation duct height and absolute M value in uniquely determining electromagnetic propagation effects. 展开更多
关键词 evaporation duct similarity theory flux-profile relationship nondimensional similarity functions stable boundary layer electromagnetic wave propagation radar detective ability
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INTS-MFS:A novel method to predict microRNA-disease associations by integrating network topology similarity and microRNA function similarity
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作者 BUWEN CAO JIAWEI LUO +2 位作者 SAINAN XIAO KAI ZHAO SHULING YANG 《BIOCELL》 SCIE 2022年第3期837-845,共9页
Identifying associations between microRNAs(miRNAs)and diseases is very important to understand the occurrence and development of human diseases.However,these existing methods suffer from the following limitation:first... Identifying associations between microRNAs(miRNAs)and diseases is very important to understand the occurrence and development of human diseases.However,these existing methods suffer from the following limitation:first,some disease-related miRNAs are obtained from the miRNA functional similarity networks consisting of heterogeneous data sources,i.e.,disease similarity,protein interaction network,gene expression.Second,little approaches infer disease-related miRNAs depending on the network topological features without the functional similarity of miRNAs.In this paper,we develop a novel model of Integrating Network Topology Similarity and MicroRNA Function Similarity(INTS-MFS).The integrated miRNA similarities are calculated based on miRNA functional similarity and network topological characteristics.INTS-MFS obtained AUC of 0.872 based on five-fold cross-validation and was applied to three common human diseases in case studies.As a results,30 out of top 30 predicted Prostatic Neoplasm-related miRNAs were included in the two databases of dbDEMC and PhenomiR2.0.29 out of top 30 predicted Lung Neoplasm-related miRNAs and Breast Neoplasm-related miRNAs were included in dbDEMC,PhenomiR2.0 and experimental reports.Moreover,INTS-MFS found unknown association with hsa-mir-371a in breast cancer and lung cancer,which have not been reported.It provides biologists new clues for diagnosing breast and lung cancer. 展开更多
关键词 Disease-related miRNA MiRNA-disease association functional similarity Network topological similarity
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Hans A.Panofsky’s Integral Similarity Function—At Fifty
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作者 Gerhard Kramm Dillon J.Amaya +1 位作者 Thomas Foken Nicole Molders 《Atmospheric and Climate Sciences》 2013年第4期581-594,共14页
Fifty years ago, Hans A. Panofsky published a paper entitled Determination of stress from wind and temperature measurements. In his famous paper, he presented a new profile function for the mean horizontal wind speed ... Fifty years ago, Hans A. Panofsky published a paper entitled Determination of stress from wind and temperature measurements. In his famous paper, he presented a new profile function for the mean horizontal wind speed under the condition of diabatic stratification that includes his integral similarity function. With his integral similarity function, he opened the door for Monin-Obukhov scaling in a wide range of micrometeorological and microclimatological applications. In a historic survey ranging from the sixties of the past century down to the present days, we present integral similarity functions for momentum, sensible heat, and water vapor for both unstable and stable stratification, where on the one hand free convection condition and on the other hand strongly stable stratification are addressed. 展开更多
关键词 Profile functions Monin-Obukhov Scaling Prandtl-Obukhov-Priestley Scaling Local similarity function Integral similarity function Obukhov Number Gradient Richardson Number Flux Richardson Number
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The Exact Measure Functions of the Images for a Class of Self-Similar Processes 被引量:2
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作者 HUANG Li-hu LI Bing-zhang LIU Lu-qin (College of Mathematics and Computer Science, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期1-6,共6页
Let X= (Ω, ■, ■_t, X_t,, θ_t, p~x) be a self-similar Markov process on (0,∞) with non-decreasing path. The exact Hausdorff and Packing measure functions of the image X([0,t] ) are obtained.
关键词 self-similar Markov process exact Hausdorff measure functions exact Packing measure function
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Hlder Estimate of Harmonic Functions on a Class of p.c.f. Self-Similar Sets
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作者 Donglei Tang Rui Hu Chunwei Pan 《Analysis in Theory and Applications》 2014年第3期296-305,共10页
In this paper we establish sharp H/51der estimates of harmonic functions on a class of connected post critically finite (p.c.f.) self-similar sets, and show that functions in the domain of Laplacian enjoy the same p... In this paper we establish sharp H/51der estimates of harmonic functions on a class of connected post critically finite (p.c.f.) self-similar sets, and show that functions in the domain of Laplacian enjoy the same property. Some weU-known examples, such as the Sierpinski gasket, the unit interval, the level 3 Sierpinski gasket, the hexagasket, the 3-dimensional Sierpinski gasket, and the Vicsek set are also considered. 展开更多
关键词 p.c.f self-similar sets Hoelder estimates harmonic function.
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The Oscillation Inequality of Harmonic Functions on Post Critically Finite Self-Similar Sets
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作者 Donglei Tang Rui Hu 《Analysis in Theory and Applications》 CSCD 2017年第2期149-156,共8页
In this paper we establish the oscillation inequality of harmonic functions and HOlder estimate of the functions in the domain of the Laplacian on connected post critically finite (p.c.f.) self-similar sets.
关键词 p.c.f. Self-similar sets oscillation inequality H61der estimate harmonic functions.
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Cantor Type Fixed Sets of Iterated Multifunction Systems Corresponding to Self-Similar Networks
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作者 Levente Simon Anna Soós 《Applied Mathematics》 2016年第4期365-374,共10页
We propose a new approach to the investigation of deterministic self-similar networks by using contractive iterated multifunction systems (briefly IMSs). Our paper focuses on the generalized version of two graph model... We propose a new approach to the investigation of deterministic self-similar networks by using contractive iterated multifunction systems (briefly IMSs). Our paper focuses on the generalized version of two graph models introduced by Barabási, Ravasz and Vicsek ([1] [2]). We generalize the graph models using stars and cliques: both algorithm construct graph sequences such that the next iteration is always based on n replicas of the current iteration, where n is the size of the initial graph structure, being a star or a clique. We analyze these self-similar graph sequences using IMSs in function of the size of the initial star and clique, respectively. Our research uses the Cantor set for the description of the fixed set of these IMSs, which we interpret as the limit object of the analyzed self-similar networks. 展开更多
关键词 Cantor Set Fixed Set Iterated function Systems Iterated Multifunction Systems Self-similar Graphs
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Functional Brain Network Learning Based on Spatial Similarity for Brain Disorders Identification
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作者 Lei Sun Tingting Guo 《Journal of Applied Mathematics and Physics》 2020年第11期2427-2437,共11页
Functional brain network (FBN) measures based on functional magnetic resonance imaging (fMRI) data, has become important biomarkers for early diagnosis and prediction of clinical outcomes in neurological diseases, suc... Functional brain network (FBN) measures based on functional magnetic resonance imaging (fMRI) data, has become important biomarkers for early diagnosis and prediction of clinical outcomes in neurological diseases, such as Alzheimer’s diseases (AD) and its prodromal state (<em>i</em>.<em>e</em>., Mild cognitive impairment, MCI). In the past decades, researchers have developed numbers of approaches for FBN estimation, including Pearson’s correction (PC), sparse representation (SR), and so on. Despite their popularity and wide applications in current studies, most of the approaches for FBN estimation only consider the dependency between the measured blood oxygen level dependent (BOLD) time series, but ignore the spatial relationships between pairs of brain regions. In practice, the strength of functional connection between brain regions will decrease as their distance increases. Inspired by this, we proposed a new approach for FBN estimation based on the assumption that the closer brain regions tend to share stronger relationships or similarities. To verify the effectiveness of the proposed method, we conduct experiments on a public dataset to identify the patients with MCIs from health controls (HCs) using the estimated FBNs. Experimental results demonstrate that the proposed approach yields statistically significant improvement in seven performance metrics over using the baseline methods. 展开更多
关键词 functional Brain Network Pearson’s Correction Sparse Representation Spatial Relationships similarITY Mild Cognitive Impairment
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On the Self-Similarity in Biological Processes 被引量:4
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作者 Oliver Szasz Gyula Peter Szigeti Andras Szasz 《Open Journal of Biophysics》 2017年第4期183-196,共14页
We show that the processes described by Avrami functions are self-similar. A comparative function characterizes a self-similar process by a certain Avrami exponent. We define the self-similar categories of some well-k... We show that the processes described by Avrami functions are self-similar. A comparative function characterizes a self-similar process by a certain Avrami exponent. We define the self-similar categories of some well-known biological processes. The method to determine the Avrami exponent by choosing the comparative function is demonstrated on the diffusion model of the growth of nuclei. We generalize the results. 展开更多
关键词 SELF-similar Process COMPARATIVE function AVRAMI EXPONENT
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A MODEL OF RANDOM PARTICLES CONSTRUCTED BY THE PRINCIPLE OF SELF-SIMILARITY AND ITS APPLICATION
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作者 程登辉 王一平 《Journal of Electronics(China)》 1993年第1期56-62,共7页
A model of random particles constructed by the operation of self-similarity in fractalgeometry is presented.The correlation function of the number density has been obtained andcan be used conveniently in theoretical s... A model of random particles constructed by the operation of self-similarity in fractalgeometry is presented.The correlation function of the number density has been obtained andcan be used conveniently in theoretical study and computer simulation for wave interaction withrandom media.As an example,this model has been applied to calculate analytically the rangedependence of volume scattering in radar echoes.The result agrees with that of Rastogi andScheucher’s simulation. 展开更多
关键词 FRACTAL GEOMETRY SELF-similarITY Correlation function
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Self-similar behavior for multicomponent coagulation
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作者 杨曼丽 卢志明 刘宇陆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第11期1353-1360,共8页
Self-similar behavior for the multicomponent coagulation system is investigated analytically in this paper. Asymptotic self-similar solutions for the constant kernel, sum kernel, and product kernel are achieved by int... Self-similar behavior for the multicomponent coagulation system is investigated analytically in this paper. Asymptotic self-similar solutions for the constant kernel, sum kernel, and product kernel are achieved by introduction of different generating functions. In these solutions, two size-scale variables are introduced to characterize the asymptotic distribution of total mass and individual masses. The result of product kernel (gelling kernel) is consistent with the Vigli-Ziff conjecture to some extent. Furthermore, the steady-state solution with injection for the constant kernel is obtained, which is again the product of a normal distribution and the scaling solution for the single variable coagulation. 展开更多
关键词 multicomponent coagulation self-similar solution generating function
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A Short Note on Self-Similar Solution to Unconfined Flow in an Aquifer with Accretion
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作者 Arieh Pistiner 《Open Journal of Fluid Dynamics》 2015年第1期51-57,共7页
In this study we refer to a non-steady state, one-dimensional (on the x-axis), unconfined and saturated flow in an aquifer, described by the Boussinesq equation, combined with accretion. In accordance with the above, ... In this study we refer to a non-steady state, one-dimensional (on the x-axis), unconfined and saturated flow in an aquifer, described by the Boussinesq equation, combined with accretion. In accordance with the above, the moving boundary of the saturated area (toward x → +∝) serves as a horizontal water flux source to the unsaturated area. As time advances, the horizontally saturated zone, lying on the x-axis, becomes wider. A self-similar solution is derived that, after some mathematical manipulation, it is described in terms of Hypergeometric functions. The long-time behaviors of the solution describe the situation at which the water flux, that penetrates horizontally to the non-saturated zone, is equal to the water flux entering into the saturated zone. 展开更多
关键词 BOUSSINESQ Equation SELF-similar Solution HYPERGEOMETRIC function
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A Functional Comparison Between English Even and Chinese ShenZhi(甚至)
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作者 原苏荣 陈可佳 《海外英语》 2015年第22期14-16,共3页
Adverbial conjunctions are still the new field to explore. This paper, based on the corpora, focuses on making a syntactic and pragmatic functional comparison between adverbial conjunctions even and shenzhi(甚至). Bot... Adverbial conjunctions are still the new field to explore. This paper, based on the corpora, focuses on making a syntactic and pragmatic functional comparison between adverbial conjunctions even and shenzhi(甚至). Both their similarities and differences are discussed. The paper finds that both of them have three connecting functions and three pragmatic functions. It aims to give the enlightments for language learning and study. 展开更多
关键词 EVEN and"甚至" functionS similarITIES and DIFFERENCES
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基于显著性区域检测的多尺度图像盲复原算法
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作者 赵小强 王涛 +1 位作者 宋昭漾 蒋红梅 《兵工学报》 EI CAS CSCD 北大核心 2024年第11期4020-4030,共11页
针对大多数基于先验的盲图像去模糊算法耗时较长和显著边缘结构提取不理想的问题,提出一种基于显著性区域检测的多尺度图像盲复原算法。为了复原出更加清晰的图像,采用由粗略到精细的多尺度交替迭代框架构建图像金字塔。在图像单一尺度... 针对大多数基于先验的盲图像去模糊算法耗时较长和显著边缘结构提取不理想的问题,提出一种基于显著性区域检测的多尺度图像盲复原算法。为了复原出更加清晰的图像,采用由粗略到精细的多尺度交替迭代框架构建图像金字塔。在图像单一尺度方面,首先提取出图像中具有强边缘结构的显著性区域,并对其施加l_(0)范数约束,提出显著映射先验;将显著性映射先验和最大后验概率相结合并引入传统图像去模糊模型中,构造出点扩散函数估算模型,利用半二次分裂算法解决模型的非凸问题;对点扩散函数进行复原时,利用点扩散函数相似度的变化量限制每个尺度中的过渡迭代;对模糊图像和最终估计的点扩散函数进行非盲解卷积,获得复原图像。实验结果表明:与现有的主流去模糊算法相比,新算法在合成数据集和真实数据集中都可以有效抑制振铃和伪影现象,得到了很好的视觉体验,且评价指标均优于对比算法,同时大大缩减了复原时间。 展开更多
关键词 多尺度图像 显著边缘结构 点扩散函数 半二次分裂算法 点扩散函数相似度
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Research and Implementation of Text Similarity System Based on Power Spectrum Analysis 被引量:1
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作者 Ying Xie Shouning Qu Huanhuan Song 《Journal of Computer and Communications》 2014年第6期7-17,共11页
The paper proposed the research and implement of text similarity system based on power spectrum analysis. It is not difficult to imagine that the signals of brain are closely linked with writing process. So we build t... The paper proposed the research and implement of text similarity system based on power spectrum analysis. It is not difficult to imagine that the signals of brain are closely linked with writing process. So we build text modeling and set pulse signal function to get the power spectrum of the text. The specific detail is getting power spectrum from economic field to build spectral library, and then using the method of power spectrum matching algorithm to judge whether the test text belonged to the economic field. The method made text similarity system finish the function of text intelligent classification efficiently and accurately. 展开更多
关键词 Pulsing Signal function Power Spectrum MATCHING Algorithm TEXT similarITY SYSTEM TEXT Intelligent Classification
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基于中心对称特征耦合仿射度量模型的图像匹配方法
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作者 李俊 《机械与电子》 2024年第9期18-24,共7页
针对当下较多图像匹配算法利用距离度量法来实现特征匹配,没考虑图像仿射变换的影响,使得匹配结果准确率不高的问题,提出了中心对称特征耦合仿射度量模型的图像匹配算法。首先,引入Forstner算子,利用像素点的GS梯度特征提取特征点;然后... 针对当下较多图像匹配算法利用距离度量法来实现特征匹配,没考虑图像仿射变换的影响,使得匹配结果准确率不高的问题,提出了中心对称特征耦合仿射度量模型的图像匹配算法。首先,引入Forstner算子,利用像素点的GS梯度特征提取特征点;然后,利用图像的Haar小波信息与中心对称像素点的灰度值,求取特征向量;接着,利用特征点之间的旋转、平移以及缩放的仿射特征,构造仿射度量模型,利用其计算出匹配的特征点对;最后,采用结构相似度(SSIM)函数,计算匹配点对的结构相似性,对匹配点对去伪求真,以求取最优匹配效果。实验结果表明,与当下匹配方法相比,所提算法不仅能更准确地实现图像匹配,而且还能够更好地适应具有仿射变换关系图像之间的匹配。 展开更多
关键词 图像匹配 中心对称特征 仿射度量模型 结构相似度函数 FORSTNER算子
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THE RANDOM SHIFT SET AND RANDOM SUB-SELF-SIMILAR SET 被引量:2
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作者 胡迪鹤 张晓敏 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期267-273,共7页
First of all the authors introduce the concepts of random sub-self-similar set and random shift set and then construct the random sub-self-similar set by a random shift set and a collection of statistical contraction ... First of all the authors introduce the concepts of random sub-self-similar set and random shift set and then construct the random sub-self-similar set by a random shift set and a collection of statistical contraction operators. 展开更多
关键词 Random sub-self-similar set random shift set Hausdorff dimension exact Hausdorff measure function Hausdorff metric
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基于改进最佳缝合线的矿井图像拼接方法
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作者 张旭辉 王悦 +5 位作者 杨文娟 陈鑫 张超 黄梦瑶 刘彦徽 杨骏豪 《工矿自动化》 CSCD 北大核心 2024年第4期9-17,共9页
煤矿井下掘进工作面高粉尘、低照度的恶劣环境导致图像信噪比较低,且有效特征点数量严重减少,处理后的图像存在较大色差和噪声,在使用最佳缝合线算法进行图像拼接时出现细节错位、缝合线处过渡不自然或拼接痕迹明显的现象。针对上述问题... 煤矿井下掘进工作面高粉尘、低照度的恶劣环境导致图像信噪比较低,且有效特征点数量严重减少,处理后的图像存在较大色差和噪声,在使用最佳缝合线算法进行图像拼接时出现细节错位、缝合线处过渡不自然或拼接痕迹明显的现象。针对上述问题,提出了一种基于改进最佳缝合线的矿井图像拼接方法。首先,对原始图像进行HSV空间变换,采用改进的Retinex算法对亮度分量进行增强,利用双边滤波函数代替中心环绕函数,以解决亮度差异大处产生的光晕问题,通过增强算法有效提高特征点提取数量。然后,采用SIFT算法提取特征点,并以余弦距离作为匹配度指标;引入像素余弦相似度作为约束项,并采用形态学操作对颜色差异强度进行改进,利用动态规划法对最佳缝合线进行搜索,以避免图像拼接处的错位现象。最后,结合渐入渐出融合算法,使图像过渡平滑,实现煤矿井下掘进工作面的图像融合。模拟井下实际工况环境进行实验验证,结果表明:基于改进最佳缝合线的矿井图像拼接方法与传统最佳缝合线算法相比,避免了颜色差异和噪声引起的错位拼接现象,拼接缝处的图像过渡更加自然,避免了“鬼影”和明显拼接缝的产生,且图像平均梯度提高2.38%,拼接时间提高32.5%,使得融合区域更加平滑自然,提高了拼接质量。 展开更多
关键词 掘进工作面 图像拼接 图像增强 最佳缝合线 RETINEX算法 改进能量函数 像素余弦相似度
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