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Maize kernel weight responses to sowing dateassociated variation in weather conditions 被引量:21
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作者 Baoyuan Zhou Yang Yue +3 位作者 Xuefang Sun Zaisong Ding Wei Ma Ming Zhao 《The Crop Journal》 SCIE CAS CSCD 2017年第1期43-51,共9页
Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions an... Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions and examine the relationship between KW, grain filling parameters, and weather factors. Maize was sown on eight sowing dates(SD) at 15–20-day intervals from mid-March to mid-July during 2012 and 2013 in the North China Plain. With sowing date delay, KW increased initially and later declined, and the greatest KW was obtained at SD6 in both years. The increased KW at SD6 was attributed mainly to kernel growth rate(Gmean), and effective grain-filling period(P). Variations in temperature and radiation were the primary factors that influenced KW and grain-filling parameters. When the effective cumulative temperature(AT) and radiation(Ra)during grain filling were 950 °C and 1005.4 MJ m-2, respectively, P and KW were greatest. High temperatures(daily maximum temperature [Tmax] > 30.2 °C) during grain filling under early sowing conditions, or low temperatures(daily minimum temperature [Tmin] < 20.7 °C) under late sowing conditions combined with high diurnal temperature range(Tmax-min> 7.1 °C) decreased kernel growth rate and ultimately final KW. When sowing was performed from May 25 through June 27, higher KW and yield of maize were obtained. We conclude that variations in environmental conditions(temperature and radiation) during grain filling markedly affect growth rate and duration of grain filling and eventually affect kernel weight and yield of maize. 展开更多
关键词 MAIZE Sowing date Weather conditions kernel weight Grain filling
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Identification of loci and candidate genes controlling kernel weight in barley based on a population for which whole genome assemblies are available for both parents 被引量:2
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作者 Hong Zhou Wei Luo +6 位作者 Shang Gao Jian Ma Meixue Zhou Yuming Wei Youliang Zheng Yaxi Liu Chunji Liu 《The Crop Journal》 SCIE CSCD 2021年第4期854-861,共8页
Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW... Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW. One is Baudin/AWCS276(BA) for which a linkage map was available. Several largeeffect QTL controlling KW were detected in this population. Another is Morex/AWCS276(MA). A linkage map with 5273 makers formed 1454 clusters, was constructed by the genotyping by sequence(GBS) data of 201 RILs from this population. A single marker was selected to represent each of the clusters and the linkage map constructed with these markers covers a total length of 1022.4 c M with an average interval of approximately 0.7 cM between loci. Three of the large-effect loci controlling KW(located on 2 HL, 6 HL,and 7 HL, respectively) identified from the BA population were also detected in the MA population under different environments. The locus on 6 HL was detected in each of the experiments conducted for both populations thus was selected for developing near isogenic lines(NILs). Apart from KW, the two isolines for each pair of the putative NILs obtained showed no significant difference for any of the morphological characteristics assessed. The average difference in KW between the isolines for all the NILs obtained was about 15% based on assessments under both glasshouse and field conditions. Taken advantage that high quality genome assemblies for both Morex and AWCS276 are available, we identified candidate genes underlying two of the three loci based on an orthologous analysis. The NILs developed and the candidate genes identified in this study should facilitate the cloning and functional analysis of genes regulating KW in barley. 展开更多
关键词 BARLEY kernel weight Near isogenic lines AWCS276
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Rapid Determination of Seed Number and Thousand Kernel Weight of Asparagus officinalis L.Using Image Processing Method
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作者 Huimin GAO Yu TIAN +1 位作者 Zhiqiang LIU Yanpo CAO 《Asian Agricultural Research》 2019年第11期53-55,共3页
Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and ... Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and large growers.Therefore,it is necessary to investigate the seed number and thousand kernel weight of A.officinalis L.This study developed a quick and accurate method to measure the seed number and thousand kernel weight of A.officinalis L.using image processing technology.Seed sample of A.officinalis L.was scanned with 200 dpi resolution,and the seed number was then obtained using Image-ProPlus software.After weighing the seeds,thousand kernel weight was finally calculated.By recording‘macro’,the batch processing of the samples can also be realized.This method is simple and accurate,and can greatly save the time of investigation. 展开更多
关键词 ASPARAGUS OFFICINALIS L. SEED number Thousand kernel weight Image processing method
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A haplotype block associated with thousand-kernel weight on chromosome 5DS in common wheat(Triticum aestivum L.) 被引量:5
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作者 Yuquan Wang Chenyang Hao +4 位作者 Jun Zheng Hongmei Ge Yang Zhou Zhengqiang Ma Xueyong Zhang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2015年第8期662-672,共11页
Spike number per unit area, number of grains per spike, and thousand-kernel weight(TKW) are important yield components for wheat(Triticum aestivum L.). TKW has the highest heritability among the three components. ... Spike number per unit area, number of grains per spike, and thousand-kernel weight(TKW) are important yield components for wheat(Triticum aestivum L.). TKW has the highest heritability among the three components. We validated 27 simple sequence repeat(SSR) loci associated with TKW in an F2:5breeding population grown in four environments. A cfd78265 bpmarker on chromosome 5DS showed the strongest association with TKW and had a significantly positive effect on TKW compared to allele cfd78259 bp, with mean increases of 5.17, 3.63, 4.11, and 5.16 g in the four environments. Markers cfd67 and cfd40 flanking cfd78 also showed significantly positive associations with TKW with increases of 5.11, 3.29, 4.31, and 4.50 g for cfd67205, and4.98, 3.49, 4.06, and 4.84 g for cfd40187 compared with cfd67203 and cfd40190in the four environments, respectively. A major quantitative trait locus for TKW spanning 2.94 c M on chromosome 5DS was detected by association mapping.Strong linkage disequilibrium(LD)(r2〉 0.2) was detected Resear among the three linked markers, which formed three haplotype blocks in the F2:5breeding population. Mean TKW differences between Hap B-I and Hap B-II were 5.80, 4.41, 4.02,and 5.06 g in the four environments, respectively. Moreover,significant LD was detected only between cfd78 and cfd67 and between cfd67 and cfd40 in a germplasm collection. This study provides a base for cloning genes related to TKW on chromosome 5DS. 展开更多
关键词 Association mapping HAPLOTYPE thousand-kernel weight Triticum oestivum
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A Multi-model Approach for Soft Sensor Development Based on Feature Extraction Using Weighted Kernel Fisher Criterion 被引量:7
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作者 吕业 杨慧中 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期146-152,共7页
Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenome... Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenomenon in subclasses,so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory.In order to solve these problems,a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy,in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses.Furthermore,the classified data are used to develop a multiple model based on support vector machine.The proposed method is applied to a bisphenol A production process for prediction of the quality index.The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor. 展开更多
关键词 feature extraction weighted kernel Fisher criterion CLASSIFICATION soft sensor
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Commutators of Weighted Lipschitz Functions and Multilinear Singular Integrals with Non-Smooth Kernels 被引量:3
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作者 LIAN Jia-li MA Bo-lin WU Huo-xiong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期353-367,共15页
This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators o... This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators on the weighted Lebesgue spaces, which extend and generalize some previous results, are obtained. 展开更多
关键词 COMMUTATOR multilinear singular integral non-smooth kernel weighted Lipschitz function weights.
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The Boundedness of Littlewood-Paley Operators with Rough Kernels on Weighted (L^q , L^p )~α (R^n) Spaces 被引量:5
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作者 Ximei Wei Shuangping Tao 《Analysis in Theory and Applications》 2013年第2期135-148,共14页
In this paper, we shall deal with the boundedness of the Littlewood-Paley operators with rough kernel. We prove the boundedness of the Lusin-area integral μΩs and Littlewood-Paley functions μΩ and μλ^* on the w... In this paper, we shall deal with the boundedness of the Littlewood-Paley operators with rough kernel. We prove the boundedness of the Lusin-area integral μΩs and Littlewood-Paley functions μΩ and μλ^* on the weighted amalgam spaces (Lω^q,L^p)^α(R^n)as 1〈q≤α〈p≤∞. 展开更多
关键词 Littlewood-Paley operator weighted amalgam space rough kernel Ap weight.
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Toeplitz Type Operator Associated to Singular Integral Operator with Variable Kernel on Weighted Morrey Spaces 被引量:1
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作者 Yuexiang He Yueshan Wang 《Analysis in Theory and Applications》 CSCD 2016年第1期90-102,共13页
Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this pa... Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this paper, the boundedness of Tb on weighted Morrey space are obtained when b belongs to the weighted Lipschitz function space and weighted BMO function space, respectively. 展开更多
关键词 Toeplitz type operator singular integral operator variable Calderon-Zygmund kernel weighted BMO function weighted Lipschitz function weighted Morrey space.
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The Boundedness of the Singular Integral Operator with Variable Calder′on-Zygmund Kernel on Weighted Morrey Spaces 被引量:1
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作者 潘亚丽 李昌文 温宗良 《Chinese Quarterly Journal of Mathematics》 2015年第1期39-46,共8页
In this paper, we will study the boundedness of the singular integral operator with variable Calder′on-Zygmund kernel on the weighted Morrey spaces Lp,κ(ω) for q′≤ p < ∞and 0 < κ < 1. Furthermore, the ... In this paper, we will study the boundedness of the singular integral operator with variable Calder′on-Zygmund kernel on the weighted Morrey spaces Lp,κ(ω) for q′≤ p < ∞and 0 < κ < 1. Furthermore, the boundedness for the commutator with BMO functions is also obtained. 展开更多
关键词 variable Calder′on-Zygmund kernels weighted Morrey spaces BMO
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Toeplitz Operator Related to Singular Integral with Non-Smooth Kernel on Weighted Morrey Space
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作者 Yuexiang He 《Analysis in Theory and Applications》 CSCD 2017年第3期240-252,共13页
Let T1 be a singular integral with non-smooth kernel or ±I, let T2 and T4 be the linear operators and let T3 = ± I. Denote the Toeplitz type operator by Tb = T1M^b Ia T2 + T3IaMbT4,where M^bf = bf, and Ib i... Let T1 be a singular integral with non-smooth kernel or ±I, let T2 and T4 be the linear operators and let T3 = ± I. Denote the Toeplitz type operator by Tb = T1M^b Ia T2 + T3IaMbT4,where M^bf = bf, and Ib is the fractional integral operator. In this paper, we investigate the boundedness of the operator Tb on the weighted Morrey space when b belongs to the weighted BMO space. 展开更多
关键词 Toeplitz operator non-smooth kernel weighted BMO fractional integral weighted Morrey space.
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Weighted estimates for strongly singular integral operators with rough kernels
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作者 黄文礼 陶祥兴 李胜宏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第6期761-768,共8页
The Fourier transform and the Littlewood-Paley theory are used to give the weighted boundedness of a strongly singular integral operator defined in this paper. The paper shows that the strongly singular integral opera... The Fourier transform and the Littlewood-Paley theory are used to give the weighted boundedness of a strongly singular integral operator defined in this paper. The paper shows that the strongly singular integral operator is bounded from the Sobolev space to the Lebesgue space. 展开更多
关键词 strongly singular integral operators rough kernels Ap weights
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Comparison of Uniform and Kernel Gaussian Weight Matrix in Generalized Spatial Panel Data Model
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作者 Tuti Purwaningsih Erfiani   《Open Journal of Statistics》 2015年第1期90-95,共6页
Panel data combine cross-section data and time series data. If the cross-section is locations, there is a need to check the correlation among locations. ρ and λ are parameters in generalized spatial model to cover e... Panel data combine cross-section data and time series data. If the cross-section is locations, there is a need to check the correlation among locations. ρ and λ are parameters in generalized spatial model to cover effect of correlation between locations. Value of ρ or λ will influence the goodness of fit model, so it is important to make parameter estimation. The effect of another location is covered by making contiguity matrix until it gets spatial weighted matrix (W). There are some types of W—uniform W, binary W, kernel Gaussian W and some W from real case of economics condition or transportation condition from locations. This study is aimed to compare uniform W and kernel Gaussian W in spatial panel data model using RMSE value. The result of analysis showed that uniform weight had RMSE value less than kernel Gaussian model. Uniform W had stabil value for all the combinations. 展开更多
关键词 Component UNIFORM weight kernel GAUSSIAN weight GENERALIZED Spatial PANEL Data Model
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Boundedness for the Singular Integral with Variable Kernel and Fractional Differentiation on Weighted Morrey Spaces 被引量:1
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作者 Chao Xue Kai Zhu Yanping Chen 《Analysis in Theory and Applications》 CSCD 2016年第3期205-214,共10页
Let T be the singular integral operator with variable kernel, T* be the adjoint of T and T# be the pseudo-adjoint of T. Let TIT2 be the product of T1 and T2, T1 o T2 be the pseudo product of T1 and T2. In this paper,... Let T be the singular integral operator with variable kernel, T* be the adjoint of T and T# be the pseudo-adjoint of T. Let TIT2 be the product of T1 and T2, T1 o T2 be the pseudo product of T1 and T2. In this paper, we establish the boundedness for commutators of these operators and the fractional differentiation operator D^γ on the weighted Morrey spaces. 展开更多
关键词 Singular integral variable kernel fractional differentiation BMO Sobolev space weighted Morrey spaces
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Dry Matter Accumulation,Moisture Content in Maize Kernel and Their Influences on Mechanical Harvesting 被引量:17
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作者 阮龙 王俊 +4 位作者 陈义红 王世济 张玮 左晓龙 陈洪俭 《Agricultural Science & Technology》 CAS 2011年第12期1857-1860,共4页
[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu... [Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index(kernel loss rate of 0.84%≤2%),while the percentage of broken kernels did not accord with the range of mechanical operation index(kernel crashing rate of 10.12%≧1%).The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting. 展开更多
关键词 Maize(Zea mays) kernel weight Moisture content Physiological mature stage
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改进YOLOv5su模型检测桃树缩叶病 被引量:1
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作者 姚凌云 周俊峰 李丽 《农业工程学报》 EI CAS CSCD 北大核心 2024年第14期109-117,共9页
为实现自然环境下桃树缩叶病的检测,该研究提出了一种基于YOLOv5su的桃树缩叶病识别改进模型DLLYOLOv5su。首先,针对桃树缩叶病目标特征变化较大的问题,在骨干网络最后一层C3模块中加入可变形自注意力模块(deformable attention,DA),使... 为实现自然环境下桃树缩叶病的检测,该研究提出了一种基于YOLOv5su的桃树缩叶病识别改进模型DLLYOLOv5su。首先,针对桃树缩叶病目标特征变化较大的问题,在骨干网络最后一层C3模块中加入可变形自注意力模块(deformable attention,DA),使模型更加关注目标区域,降低背景对模型的影响,提高模型在复杂背景下的拟合能力。其次在SPPF(fast spatial pyramid pooling)模块中引入LSKA(large separable kernel attention)结构,大核卷积增大了模型的感受野,使模型能够关注更多信息。最后,提出了LAWD(lightweight adaptive weighted downsampling)模块,使用轻量化的下采样结构替换卷积模块,减少计算开销。在桃树缩叶病数据集上进行试验,结果显示,DLL-YOLOv5su模型权重大小为17.6 MB,检测速度为83帧/s。识别准确率P、召回率R和平均精度均值mAP_(50)分别达到了80.7%、73.1%和80.4%,相较于原始YOLOv5su分别提高了4.2、2.4和4.3个百分点。与YOLOv3-tiny、Faster R-CNN、YOLOv7和YOLOv8相比mAP_(50)分别高出了28.5、11.8、2.1和4.1个百分点。改进模型识别精度高,误检、漏检率低,检测速度满足实时检测的要求,可以为桃树缩叶病的实时监测和预警提供参考。 展开更多
关键词 图像处理 病害 缩叶病 目标检测 YOLOv5su 可变形自注意力 大核卷积 轻量化
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河南省冬小麦籽粒质量评价的气象指标分析
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作者 成林 韩耀杰 胡程达 《气象与环境学报》 2024年第2期69-76,共8页
选用2008年、2010—2014年、2019年河南省共630份冬小麦样本及对应时段的气象资料,采用多重比较、Logistic多元回归等方法,构建河南省冬小麦籽粒质量达二等及以上的气象指标。结果表明:冬小麦籽粒容重与花粒期平均空气相对湿度呈显著负... 选用2008年、2010—2014年、2019年河南省共630份冬小麦样本及对应时段的气象资料,采用多重比较、Logistic多元回归等方法,构建河南省冬小麦籽粒质量达二等及以上的气象指标。结果表明:冬小麦籽粒容重与花粒期平均空气相对湿度呈显著负相关,与日照时数呈显著正相关;籽粒不完善粒与空气相对湿度、降水量和降水日数为显著正相关;冬小麦籽粒质量与各旬气象因子的相关性呈动态变化。不同地区影响冬小麦籽粒容重的关键气象因子不同,河南北部地区为光照和气温,河南东部主要为气温,河南南部为气温和降水量。冬小麦籽粒质量气象指标评价等级与实际籽粒质量等级指标的一致率为84%,不完善粒评价一致率为100%。近30 a河南省冬小麦质量气象等级达二等的平均频率为79.7%(除河南西部),气象条件整体上有利于河南省冬小麦籽粒质量的提高。 展开更多
关键词 籽粒容重 不完善粒 气温日较差 气象因子
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加权核范数最小化和改进小波阈值函数的图像去噪算法
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作者 郭昕刚 许连杰 +1 位作者 程超 霍金花 《国防科技大学学报》 EI CAS CSCD 北大核心 2024年第2期238-246,共9页
针对加权核范数最小化算法存在结构残余噪声以及无法较好地保持图像边缘结构的问题,提出基于加权核范数最小化和改进小波阈值函数的图像去噪算法。利用全变分模型对噪声图像进行初步去噪,使用噪声图像与初步去噪后的图像进行差分运算,... 针对加权核范数最小化算法存在结构残余噪声以及无法较好地保持图像边缘结构的问题,提出基于加权核范数最小化和改进小波阈值函数的图像去噪算法。利用全变分模型对噪声图像进行初步去噪,使用噪声图像与初步去噪后的图像进行差分运算,对差分后得到的噪声残差图像使用改进的小波阈值函数去噪,将小波去噪后的残差图像与初步去噪图像叠加,将叠加后的图像使用基于残余噪声水平迭代的加权核范数最小化算法进行二次去噪。相较于当下主流去噪算法,经该算法处理后的图像的PSNR和SSIM值均有所提升,能够更好地保持图像的纹理结构,且在高噪声环境下效果更佳。 展开更多
关键词 加权核范数 小波变换 噪声残差 全变分
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中国新经济新动能的测度评价及动态分布特征研究
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作者 王天桥 《中国科技论坛》 CSSCI 北大核心 2024年第6期22-34,共13页
从新产业、新业态、新技术、新资本4个维度构建中国新经济新动能评价指标体系,利用熵权TOPSIS测度中国新经济新动能发展指数,并借助核密度估计、泰尔指数和收敛模型分析中国新经济新动能的综合发展水平、地区差异及收敛性。结果表明,中... 从新产业、新业态、新技术、新资本4个维度构建中国新经济新动能评价指标体系,利用熵权TOPSIS测度中国新经济新动能发展指数,并借助核密度估计、泰尔指数和收敛模型分析中国新经济新动能的综合发展水平、地区差异及收敛性。结果表明,中国新经济新动能整体呈稳步上升趋势,子系统呈现“新产业>新业态>新技术>新资本”的分布格局;三大区域新经济新动能差异显著,呈现“东部>中部>西部”的发展态势。从地区差异角度而言,中国新经济新动能发展非均衡性逐步凸显,但未发生两极分化现象;中国新经济新动能总体差异呈下降趋势,主要来源为地区间差异。从收敛性看,全国以及三大区域新经济新动能具有显著的σ收敛和绝对β收敛趋势;不同区域新经济新动能条件β收敛具有差异。 展开更多
关键词 新经济 新动能 熵权TOPSIS 核密度估计 泰尔指数
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多向加权Tsallis熵最大化导向的自动阈值分割方法 被引量:1
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作者 邹耀斌 邓世成 +3 位作者 孟祥丹 周欢 孙水发 陈鹏 《电子学报》 EI CAS CSCD 北大核心 2024年第1期129-143,共15页
受噪声或随机细节、目标和背景的大小比例、成像时的点扩散等不同因素的影响,许多图像的灰度直方图呈现为无模态、单模态、双模态或者多模态样式.为了在统一框架内处理这4种不同模态情形下的自动阈值选择问题,本文提出了一种多向加权Tsa... 受噪声或随机细节、目标和背景的大小比例、成像时的点扩散等不同因素的影响,许多图像的灰度直方图呈现为无模态、单模态、双模态或者多模态样式.为了在统一框架内处理这4种不同模态情形下的自动阈值选择问题,本文提出了一种多向加权Tsallis熵最大化导向的自动阈值分割方法(Multi-directional Weighted Tsallis Entropy,MWTE).基于新设计的反正切方向性卷积核的多尺度乘积效应,该方法将不同模态的灰度直方图转化为统一的单模态右偏灰度直方图.在4个不同方向上提取出这种特殊的单模态右偏灰度直方图后,通过多向加权策略构建出与原始图像灰度值紧密相关的加权Tsallis熵目标函数,并以该目标函数取最大值时对应的灰度值作为最终分割阈值.本文将提出的方法和3个阈值分割方法、1个软分割方法、1个活动轮廓分割方法以及1个自动聚类分割方法进行了比较.在4种不同模态情形下的4幅合成图像和50幅真实世界图像上的实验结果表明,本文提出的方法虽然在计算效率方面不占有优势,但它对不同模态的测试图像具有更稳健的分割适应性,且在量化分割精度所用的马修斯相关系数方面优于其他6个分割方法. 展开更多
关键词 阈值分割 Tsallis熵差 加权Tsallis熵 反正切方向性卷积核 多尺度乘积效应 马修斯相关系数
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EDGEWORTH EXPANSION FOR NEAREST NEIGHBOR- KERNEL ESTIMATE AND RANDOM WEIGHTING APPROXIMATION OF CONDITIONAL DENSITY
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作者 Yu ZhaopingInstitute of Electronic Technique,Zhengzhou450 0 0 4 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第2期167-172,共6页
In this paper,Edgeworth expansion for the nearest neighbor\|kernel estimate and random weighting approximation of conditional density are given and the consistency and convergence rate are proved.
关键词 Random weighting method Edgeworth expansion nearest neighbor\|kernel estimate.
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