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An Improved Interval-Valued Picture Fuzzy TOPSIS Approach Based on New Divergence Measures for Risk Assessment
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作者 Sijia Zhu Yuhan Li +3 位作者 Prasanalakshmi Balaji Akila Thiyagarajan Rajanikanth Aluvalu Zhe Liu 《Computer Modeling in Engineering & Sciences》 2025年第8期2099-2121,共23页
While interval-valued picture fuzzy sets(IvPFSs)provide a powerful tool for modeling uncertainty and ambiguity in various fields,existing divergence measures for IvPFSs remain limited and often produce counterintuitiv... While interval-valued picture fuzzy sets(IvPFSs)provide a powerful tool for modeling uncertainty and ambiguity in various fields,existing divergence measures for IvPFSs remain limited and often produce counterintuitive results.To address these shortcomings,this paper introduces two novel divergencemeasures for IvPFSs,inspired by the Jensen-Shannon divergence.The fundamental properties of the proposed measures-non-degeneracy,symmetry,triangular inequality,and boundedness-are rigorously proven.Comparative analyses with existing measures are conducted through specific cases and numerical examples,clearly demonstrating the advantages of our approach.Furthermore,we apply the new divergence measures to develop an enhanced interval-valued picture fuzzy TOPSIS method for risk assessment in construction projects,showing the practical applicability and effectiveness of our contributions. 展开更多
关键词 Interval-valued picture fuzzy sets divergence measure Jensen-Shannon divergence TOPSIS risk assessment
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Bayesian Network Reconstruction and Iterative Divergence Problem Solving Method Based on Norm Minimization
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作者 Kuo Li Aimin Wang +2 位作者 Limin Wang Yuetan Zhao Xinyu Zhu 《Computer Modeling in Engineering & Sciences》 2025年第4期617-637,共21页
A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves... A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves precise adjustment of the network structure by constructing a preliminary random network model and introducing small-world network characteristics and combines L1 norm minimization regularization techniques to control model complexity and optimize the inference process of variable dependencies.In the experiment of game network reconstruction,when the success rate of the L1 norm minimization model’s existence connection reconstruction reaches 100%,the minimum data required is about 40%,while the minimum data required for a sparse Bayesian learning network is about 45%.In terms of operational efficiency,the running time for minimizing the L1 normis basically maintained at 1.0 s,while the success rate of connection reconstruction increases significantly with an increase in data volume,reaching a maximum of 13.2 s.Meanwhile,in the case of a signal-to-noise ratio of 10 dB,the L1 model achieves a 100% success rate in the reconstruction of existing connections,while the sparse Bayesian network had the highest success rate of 90% in the reconstruction of non-existent connections.In the analysis of actual cases,the maximum lift and drop track of the research method is 0.08 m.The mean square error is 5.74 cm^(2).The results indicate that this norm minimization-based method has good performance in data efficiency and model stability,effectively reducing the impact of outliers on the reconstruction results to more accurately reflect the actual situation. 展开更多
关键词 Bayesian norm minimization network reconstruction iterative divergence SPARSITY
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Chloroplast genome characterization and divergence time estimation of Persicaria capitata
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作者 Xianfa Zeng Chang Liu +6 位作者 Xiaoying Yang Xinyue Wang Jiangli Luo Ying Zhou Liyan Zhang Zengjie Gao Xiang Pu 《Acupuncture and Herbal Medicine》 2025年第1期89-102,共14页
Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Pers... Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Persicaria nepalensis,Persicaria japonica,Persicaria chinensis,Persicaria filiformis,Persicaria perfoliata,Persicaria pubescens,Persicaria hnydropiper.Methods:The Illumina HiSeq high-throughput sequencing platform was used for the first time for P.capitata cp genome sequencing.NOVOPlasty and CpGAVAS2 were used for assembly and annotation,and Codon W,DnaSP,and MISA were used to conduct a series of comparative genomic analyses between the plant and seven species of the same genus.A phylogenetic tree was constructed using the maximum likelihood(ML)and neighbor-joining(NJ)methods,and divergence time was estimated using BEAST.Results:The total length of P.capitata cp genome was 158,821 bp,with a guanine and cytosine(GC)content of 38.0%,exhibiting a typical circular tetrad structure.The genome contains 127 annotated genes,including 82 protein-coding and 45 tRNA-encoding genes.The cp genome harbors simple sequence repeat(SSR)loci primarily composed of A/T.The conserved species structure of this genus is reinforced by the expansion and contraction of the inverted repeat(IR)region.The non-coding regions of the cp genomes exhibited significant differences among the genera.Six different mutation hotspots(psbK-psbI,atpI-rps2,petN-psbD,atpB-rbcL,cemA-petA,ndhI-ndhA-ycf1)were screened from the non-coding regions of genes with high nucleotide variability(pI).These hotspots were expected to define the phylogenetic species of Persicaria.Furthermore,phylogenetic analysis of Polygonaceae plants showed that P.capitata was more closely related to P.chinensis than P.nepalensis.Analysis of divergence time indicated that Polygonaceae originated in the Late Cretaceous(~180 Ma)and began to differentiate during the Middle Miocene.Persicaria differentiated~66.44 million years ago,during the Miocene.Conclusions:Our findings will serve as a scientific basis for further research on species identification and evolution,population genetics,and phylogenetic analysis of P.capitata.Further,we provide valuable information for understanding the origin and evolution of Persicaria in Polygonaceae and estimating the differentiation time of Persicaria and its population. 展开更多
关键词 Chloroplast genomes Comparative analysis divergence time Persicaria capitata Phylogenetic relationship
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Development of AHP-Based Divergence Distance Measure between P,q,r-Spherical Fuzzy Sets with Applications in Multi-Criteria Decision Making
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作者 Shah Zeb Khan Muhammad Rahim +3 位作者 Adel M.Widyan A.Almutairi Njood Shaher Ethaar Almutire Hamiden Abd El-Wahed Khalifa 《Computer Modeling in Engineering & Sciences》 2025年第5期2185-2211,共27页
This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy ess... This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy essential axiomatic properties or produce unintuitive outcomes.To address these limitations,we propose a new three-dimensional divergence-based DM that ensures mathematical consistency,enhances the discrimination of information,and adheres to the axiomatic framework of distance theory.Building on this foundation,we construct a multi-criteria decision-making(MCDM)model that utilizes the proposed DM to evaluate and rank alternatives effectively.The applicability and robustness of the model are validated through a practical case study,demonstrating that it leads to more rational,consistent,and reliable decision outcomes compared to existing approaches. 展开更多
关键词 p q r-spherical fuzzy sets divergence distance measures AHP decision making
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Divergences in neuroendocrine prostate cancer frequency as recognized by anatomic pathologists,clinicians,and basic scientists
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作者 Kenneth A Iczkowski Mamta Parikh 《Asian Journal of Andrology》 2025年第1期1-3,共3页
As a practicing anatomic pathologist specialized in urologic pathology,a vast difference may be observed between what pathologists designate as neuroendocrine(or small cell)carcinoma of the prostate,and what clinician... As a practicing anatomic pathologist specialized in urologic pathology,a vast difference may be observed between what pathologists designate as neuroendocrine(or small cell)carcinoma of the prostate,and what clinicians or basic scientists define as such. 展开更多
关键词 urologic pathology anatomic pathologists CLINICIANS neuroendocrine prostate cancer basic scientists divergenceS anatomic pathologist
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基于随机游走模型和KL-divergence的聚类算法 被引量:6
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作者 何会民 《计算机工程》 CAS CSCD 北大核心 2008年第16期224-226,共3页
聚类分析在数据挖掘领域有着广泛的应用,该文提出一个聚类新思路,它不需要任何参数的假设,只基于数据两两之间的相似性。该方法假设数据点之间存在随机游走关系,根据数据相似性构造随机游走过程的转移矩阵,当随机游走过程进入收敛期后,... 聚类分析在数据挖掘领域有着广泛的应用,该文提出一个聚类新思路,它不需要任何参数的假设,只基于数据两两之间的相似性。该方法假设数据点之间存在随机游走关系,根据数据相似性构造随机游走过程的转移矩阵,当随机游走过程进入收敛期后,t阶转移矩阵揭示了数据点的分布。用迭代方法寻找最小的KL-divergence来对这些分布聚类。该方法具有严谨的概率理论基础,避免了传统算法需要参数假设、限于局部最优等不足。实验表明,该算法具有较优的聚类效果。 展开更多
关键词 聚类 随机游走 KL散度
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Molecular evolution and functional divergence of HAK potassium transporter gene family in rice(Oryza sativa L.) 被引量:25
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作者 Zefeng Yang Qingsong Gao +3 位作者 Changsen Sun Wenjuan Li Shiliang Gu Chenwu Xu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第3期161-172,共12页
The high-affinity K+ (HAK) transporter gene family is the largest family in plant that functions as potassium transporter and is important for various aspects of plant life. In the present study, we identified 27 m... The high-affinity K+ (HAK) transporter gene family is the largest family in plant that functions as potassium transporter and is important for various aspects of plant life. In the present study, we identified 27 members of this family in rice genome. The phylogenetic tree divided the land plant HAK transporter proteins into 6 distinct groups. Although the main characteristic of this family was established before the origin of seed plants, they also showed some differences between the members of non-seed and seed plants. The HAK genes in rice were found to have expanded in lineage-specific manner after the split of monocots and dicots, and both segmental duplication events and tandem duplication events contributed to the expansion of this family. Functional divergence analysis for this family provided statistical evidence for shifted evolutionary rate after gene duplication. Further analysis indicated that both point mutant with positive selection and gene conversion events contributed to the evolution of this family in rice. 展开更多
关键词 HAK potassium transporter gene family RICE functional divergence gene conversion positive selection
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Tunable 3D Nanofiber Architecture of Polycaprolactone by Divergence Electrospinning for Potential Tissue Engineering Applications 被引量:8
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作者 George Z.Tan Yingge Zhou 《Nano-Micro Letters》 SCIE EI CAS 2018年第4期314-323,共10页
The creation of biomimetic cell environments with micro and nanoscale topographical features resembling native tissues is critical for tissue engineering. To address this challenge, this study focuses on an innovative... The creation of biomimetic cell environments with micro and nanoscale topographical features resembling native tissues is critical for tissue engineering. To address this challenge, this study focuses on an innovative electrospinning strategy that adopts a symmetrically divergent electric field to induce rapid self-assembly of aligned polycaprolactone(PCL) nanofibers into a centimeter-scale architecture between separately grounded bevels. The 3D microstructures of the nanofiber scaffolds were characterized through a series of sectioning in both vertical and horizontal directions. PCL/collagen(type I)nanofiber scaffolds with different density gradients were incorporated in sodium alginate hydrogels and subjected to elemental analysis. Human fibroblasts were seeded onto the scaffolds and cultured for 7 days. Our studies showed that the inclination angle of the collector had significant effects on nanofiber attributes, including the mean diameter, density gradient, and alignment gradient. The fiber density and alignment at the peripheral area of the 45°-collector decreased by 21% and 55%, respectively, along the z-axis,while those of the 60°-collector decreased by 71% and 60%, respectively. By altering the geometry of the conductive areas on the collecting bevels, polyhedral and cylindrical scaffolds composed of aligned fibers were directly fabricated. By using a four-bevel collector, the nanofibers formed a matrix of microgrids with a density of 11%. The gradient of nitrogen-to-carbon ratio in the scaffold-incorporated hydrogel was consistent with the nanofiber density gradient. The scaffolds provided biophysical stimuli to facilitate cell adhesion, proliferation, and morphogenesis in 3D. 展开更多
关键词 divergence electrospinning 3D nanofiber scaffold Tissue engineering Microstructure gradient
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THE DIVERGENCE OF LAGRANGE INTERPOLATION IN EQUIDISTANT NODES 被引量:5
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作者 Lu Zhikang and Xia Mao (Hangzhou Teacher’s College, China)Department of Mathematics Hangzhou Teacher’s College Hangzhou,310012 P.R.China 《Analysis in Theory and Applications》 2003年第2期160-165,共6页
It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to \x\ at e-qually spaced nodes in [-1.1] diverges everywhere. except at zero and the end-points. In this paper we show tha... It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to \x\ at e-qually spaced nodes in [-1.1] diverges everywhere. except at zero and the end-points. In this paper we show that the sequence of Lagrange interpolation polynomials corresponding to the functions which possess better smoothness on equidistant nodes in [-1.1] still diverges every -where in the interval except at zero and the end-points. 展开更多
关键词 lagrange interpolation equidistant nodes divergence
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Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata(L.) Pierre., accessions in Bay Islands 被引量:4
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作者 I. Jaisankar M. Sankaran +1 位作者 D.R. Singh V. Damodaran 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期351-358,共8页
In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducte... In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length (75.51 mm), pod width (34.62 mm), pod thickness (17.55 mm), 100 pod weight (770.33 g), seed width (21.23 mm), 100 seed weight (377.00 g), oil percentage (43.92%) and germination percentage (94.7%). However, the maximum seed length (26.46 mm) was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 (2.50 and 2.44 respectively). The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 (for seed length) to 0.95 (pod length) and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance (10.238)shown by cluster VI and the maximum inter cluster distance (17.021) between V and HI followed by III and II (15.942). Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations. 展开更多
关键词 Pongamia pinnata correlation heritabi!ity genetic gain genetic divergence oil percentage
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Experimental Study on the Effects of Magnetic Field Configuration near the Channel Exit on the Plume Divergence of Hall Thrusters 被引量:3
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作者 于达仁 李杰 +2 位作者 李鸿 李勇 江滨浩 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期714-720,共7页
Experimental investigations into the effects of the magnetic field configuration near the channel exit on the plume of Hall thrusters were conducted. The magnetic field configuration near the channel exit is character... Experimental investigations into the effects of the magnetic field configuration near the channel exit on the plume of Hall thrusters were conducted. The magnetic field configuration near the channel exit is characterized by the inclination angle between the magnetic field lines and the thruster radial direction. Different inclination angles were obtained by varying the current ratio in the coils. The plume divergence angles were measured by a dual-directed probe. The results showed that the plume divergence angle increased obviously with the increase in the magnitude of the inclination angle near the channel exit. Therefore, in order to optimize the magnetic field for reducing plume divergence, the magnitude of the inclination angle should be reduced as much as possible. It suggests that the magnetic field configuration near the channel exit is another important factor that affects plume divergence. 展开更多
关键词 Hall thruster plume divergence magnetic field configuration inclination angle
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THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|~α(2<α<4) AT EQUIDISTANT NODES 被引量:3
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作者 Hui Su Shusheng Xu 《Analysis in Theory and Applications》 2006年第2期146-154,共9页
It is a classical result of Bernstein that the sequence of Lagrange interpolation polumomials to |x| at equally spaced nodes in [-1, 1] diverges everywhere, except at zero and the end-points. In the present paper, t... It is a classical result of Bernstein that the sequence of Lagrange interpolation polumomials to |x| at equally spaced nodes in [-1, 1] diverges everywhere, except at zero and the end-points. In the present paper, toe prove that the sequence of Lagrange interpolation polynomials corresponding to |x|^α (2 〈 α 〈 4) on equidistant nodes in [-1, 1] diverges everywhere, except at zero and the end-points. 展开更多
关键词 Lagrange interpolation equidistant nodes divergence
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New Evidence for Improving Omega Estimation by Explicitly Considering Horizontal Divergence 被引量:2
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作者 YUAN Zhuojian QI Jindian +3 位作者 GAO Shouting FENG Yerong XU Pengcheng WU Naigeng 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期449-456,共8页
It is well known that the quasi-geostrophic (QG) omega equation with only two contributors respectively associated with vorticity advection (VA) and temperature advection is derived for midlatitude synoptic-scale ... It is well known that the quasi-geostrophic (QG) omega equation with only two contributors respectively associated with vorticity advection (VA) and temperature advection is derived for midlatitude synoptic-scale systems only.Based on reliable reanalysis data,new evidence revealed by cyclonic and anticyclonic cases indicates that forecasters might sometimes experience problems by paying too much attention to the 500-hPa VA when estimating vertical motions not only in subtropical systems but also in systems meeting all the assumptions of the QG omega equation.Our investigations also showed that explicitly considering the vertical profiles of horizontal divergence could allow for better interpretation of vertical motions and weather in these real cases,suggesting that this equation might not be sufficient due to the presence of only two horizontaldivergence-related (HDR) mechanisms and the absence of other HDR mechanisms,e.g.,frictional force,mountain barriers,diabatic/adiabatic processes,and acceleration/deceleration of air flows. 展开更多
关键词 omega estimation weather forecast horizontal divergence vertical motion
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Gapless genome assembly of azalea and multi-omics investigation into divergence between two species with distinct f lower color 被引量:6
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作者 Shuai Nie Shi-Wei Zhao +15 位作者 Tian-Le Shi Wei Zhao Ren-Gang Zhang Xue-Chan Tian Jing-Fang Guo Xue-Mei Yan Yu-Tao Bao Zhi-Chao Li Lei Kong Hai-Yao Ma Zhao-Yang Chen Hui Liu Yousry AEl-Kassaby Ilga Porth Fu-Sheng Yang Jian-Feng Mao 《Horticulture Research》 SCIE CSCD 2023年第1期193-206,共14页
The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence be... The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence between two parental species with different f lower color widely used for azalea breeding.Gapless genome assembly was generated for the yellow-f lowered azalea,Rhododendron molle.Comparative genomics found recent proliferation of long terminal repeat retrotransposons(LTR-RTs),especially Gypsy,has resulted in a 125 Mb(19%)genome size increase in species-specific regions,and a significant amount of dispersed gene duplicates(13402)and pseudogenes(17437).Metabolomic assessment revealed that yellow f lower coloration is attributed to the dynamic changes of carotenoids/f lavonols biosynthesis and chlorophyll degradation.Time-ordered gene co-expression networks(TO-GCNs)and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct f lower pigmentation.B3 and ERF TFs were found dominating the gene regulation of carotenoids/f lavonols characterized pigmentation in R.molle,while WRKY,ERF,WD40,C2H2,and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-f lowered R simsii.This study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding. 展开更多
关键词 divergence YELLOW COLLECTIVE
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病理心电信号的Jensen-Shannon divergence分析
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作者 许欢 孟浩 王俊 《北京生物医学工程》 2012年第6期565-569,共5页
目的研究快速区分不同病理心电信号的算法是当前临床医学诊断的研究热点之一。方法本文采用基于Jensen-Shannon divergence的复杂度分析方法,从MIT-BIH标准数据库中提取正常窦性心率、房性早搏、窦性心动过缓信号,分别计算它们的复杂度... 目的研究快速区分不同病理心电信号的算法是当前临床医学诊断的研究热点之一。方法本文采用基于Jensen-Shannon divergence的复杂度分析方法,从MIT-BIH标准数据库中提取正常窦性心率、房性早搏、窦性心动过缓信号,分别计算它们的复杂度。结果正常心率信号复杂度最高,窦性心动过缓信号次之,房性早搏最低。方差检验结果表明,此方法得出的3种信号的复杂度具有显著性差异。结论病理心电信号的Jensen-Shannon divergence分析对临床医学检测和诊断房性早搏、窦性心动过缓信号有很好的借鉴意义。 展开更多
关键词 Jensen—Shannon divergence 复杂度 房性早搏 窦性心动过缓 电信号
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Some Results on a Class of Nonlinear Degenerate Parabolic Equations Not in Divergence Form 被引量:5
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作者 周文书 伍卓群 高文杰 《Northeastern Mathematical Journal》 CSCD 2003年第4期291-294,共4页
关键词 degenerate parabolic equation not in divergence form EXISTENCE nonunique-ness LOCALIZATION
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THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|~a 被引量:2
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作者 Zhikang Lu Xifang Ge 《Analysis in Theory and Applications》 2005年第4期385-394,共10页
This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the rune tion f(z) =|x|^α(1〈α〈2) on [-1,1] can diverge everywhere in the interval except at zero and the end-points.
关键词 lagrange interpolation polynomial equidistant nodes diverge
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Sexual Dimorphism of Head Size in Phrynocephalus przewalskii: Testing the Food Niche Divergence Hypothesis 被引量:2
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作者 Wei ZHAO Naifa LIU 《Asian Herpetological Research》 SCIE 2013年第4期242-247,共6页
Sexual size dimorphism (SSD) is a general phenomenon in lizards, and can evolve through sexual selection or natural selection. But natural selection, which was thought to operate mainly through reducing the competit... Sexual size dimorphism (SSD) is a general phenomenon in lizards, and can evolve through sexual selection or natural selection. But natural selection, which was thought to operate mainly through reducing the competition be- tween the two sexes (niche divergence hypothesis), gave rise to a lot of controversy. We tested the niche divergence hypothesis in the toad-headed lizard Phrynocephalus przewalskii by comparing diet composition and prey sizes between males and females. The species was found to be sexual dimorphic, with males having relatively larger snout-vent length, head width, head length, and tail length, while females have relatively larger abdomen length. Based on analysis of 93 studied stomachs, a total of 1359 prey items were identified. The most common prey items were formicid, lygaeid and tenebrionid. The two sexes did not differ in the relative proportions of prey size categories they consumed and the dietary overlap based on prey species was high (O = 0.989). In addition, the meal size, the volume or any maximal dimension of the largest prey item in the stomach was not explained by the sexes. According to our results, food niche divergence might not play an important role in the SSD evolution ofP. przewalskii. 展开更多
关键词 Phrynocephalus przewalskii sexual size dimorphism niche divergence food composition prey size
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