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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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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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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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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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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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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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融合相似性度量加权核偏最小二乘的烷烃气体定量分析方法 被引量:1
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作者 李忠兵 刘雅杰 +2 位作者 梁海波 倪朋勃 闫碧 《电子测量与仪器学报》 CSCD 北大核心 2024年第5期210-218,共9页
烃类气体含量的有效监测是油气勘探开采过程中安全保障的重要环节。红外光谱法作为一种安全高效的检测方法,受到现场工程师的关注,但主要采用离线模型进行测量,无法较好应对现场复杂的工况及变化多样的非线性影响因素,导致离线模型不更... 烃类气体含量的有效监测是油气勘探开采过程中安全保障的重要环节。红外光谱法作为一种安全高效的检测方法,受到现场工程师的关注,但主要采用离线模型进行测量,无法较好应对现场复杂的工况及变化多样的非线性影响因素,导致离线模型不更新而难以维持较高的预测精度。为此,提出了一种融合相似性度量加权核偏最小二乘的即时学习建模策略。首先设计了一种多相似性度量准则融合的样本相似性判别依据,有效筛选历史样本用于在线建模,其次在局部PLS模型中引入非线性核函数,实现非线性特征的有效提取,弥补线性偏最小二乘模型的非线性处理能力。在构建的多组分混合气体红外光谱数据上的实验结果验证了该方法的有效性,拟合优度R2达到0.994 1,RMSE和MRE相比PLS模型分别提升了43.6%和85.8%,可有效用于烃类气体红外光谱定量分析模型的在线更新与高精度预测。 展开更多
关键词 烷烃气体 红外光谱 即时学习 相似性度量 非线性核函数
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基于双前沿面数据包络分析的云制造服务功能匹配
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作者 张志颖 张红艳 +1 位作者 刘茹梦 魏旭光 《计算机集成制造系统》 EI CSCD 北大核心 2024年第4期1374-1388,共15页
针对云制造环境下功能匹配过程中属性权重需提前确定,进而影响匹配精度的问题,提出了一种基于本体相似度的双前沿面数据包络分析(DEA)匹配方法,该方法根据总体几何平均相似度进行服务排序,并自动生成属性权重。首先,为了提高匹配效率,... 针对云制造环境下功能匹配过程中属性权重需提前确定,进而影响匹配精度的问题,提出了一种基于本体相似度的双前沿面数据包络分析(DEA)匹配方法,该方法根据总体几何平均相似度进行服务排序,并自动生成属性权重。首先,为了提高匹配效率,从基本信息、类型、状态及功能四方面对云制造服务与需求进行描述;然后,引入信息量并改进相似度计算方法,提出基于概念语义距离、信息量和概念层次顺序的本体概念综合语义相似度计算方法;在此基础上,运用双前沿面DEA模型衡量总体效率,以此进行服务排序;最后通过算例证明了该方法的可行性。所提方法为改善云制造服务功能匹配效果提供了参考。 展开更多
关键词 云制造服务 功能匹配 双前沿面数据包络分析 综合相似度
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模糊超图相似性测度及其在决策中的应用
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作者 党明聪 耿生玲 《计算机仿真》 2024年第2期373-379,429,共8页
相似性度量在模糊环境中起着重要作用。通过距离测度进行相似性判断的方法通常利用两个模糊系统间的欧几里得距离,明科夫斯基距离和曼哈顿距离进行测度。引入一种新的基于欧几里得距离求解模糊集距离相似性测度的方法,通过分析将此方法... 相似性度量在模糊环境中起着重要作用。通过距离测度进行相似性判断的方法通常利用两个模糊系统间的欧几里得距离,明科夫斯基距离和曼哈顿距离进行测度。引入一种新的基于欧几里得距离求解模糊集距离相似性测度的方法,通过分析将此方法推广至模糊超图。并提出了三种与模糊集和模糊超图相关的算法。使用此算法可以应对不同类型的决策分析。为了检验上述方法的效率与可靠性,利用多个实例进行验证,证明了所提出新的距离相似性测度方法的合理性和有效性。 展开更多
关键词 相似性 模糊集 模糊超图 距离相似性测度 拟合函数
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输气管道压气站节能运行优化研究
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作者 杨德伟 《石油石化节能与计量》 CAS 2024年第8期47-51,共5页
为实现输气管道压气站运行能耗的优化,首先对压缩机的性能曲线进行了修正,以避免相似换算和机组劣化对功率、压比等参数的影响;再以总能耗成本最低为目标函数,以压缩机开关状态和出站压力为优化变量,在诸多等式约束和不等式约束的限定下... 为实现输气管道压气站运行能耗的优化,首先对压缩机的性能曲线进行了修正,以避免相似换算和机组劣化对功率、压比等参数的影响;再以总能耗成本最低为目标函数,以压缩机开关状态和出站压力为优化变量,在诸多等式约束和不等式约束的限定下,对优化方案进行求解,并对比了优化前后的节能效果。结果表明,即使压缩机为同一型号、同一厂家,不同压缩机之间仍存在性能差异;修正后的功率和压力与现场实测值相比,整体误差较小,满足现场工程精度的要求;优化后,压缩机总功率从134.932 MW降低至112.129 MW,降幅为16.90%,电驱压缩机组平均机组效率提高至47.77%,燃驱压缩机组平均机组效率提高至37.42%,总能耗成本降幅为16.94%。达到输气管道节能降耗的目的。 展开更多
关键词 输气管道 压气站 运行优化 节能 相似换算 目标函数
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基于改进DFVDFF网络的变焦深度测量
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作者 赵涂昊 夏小东 +1 位作者 付茂栗 王觅 《计算机应用》 CSCD 北大核心 2024年第S01期223-228,共6页
针对差分聚焦体(DFV)与变焦深度测量(DFF)联合应用的网络(简称为DFVDFF)精度较低的问题,首先,将特征提取模块的网络结构替换为UNet++,并在深度信息提取模块内增加注意力机制,通过关注重要的特征并融合深层特征和浅层特征提升网络预测的... 针对差分聚焦体(DFV)与变焦深度测量(DFF)联合应用的网络(简称为DFVDFF)精度较低的问题,首先,将特征提取模块的网络结构替换为UNet++,并在深度信息提取模块内增加注意力机制,通过关注重要的特征并融合深层特征和浅层特征提升网络预测的精度;然后,针对DFVDFF生成的深度图纹理边界模糊的问题,使用结构相似度和平滑平均绝对误差融合的损失函数替换原有的平滑平均绝对误差损失函数,通过提升损失函数对纹理边界的敏感程度引导网络生成更清晰的边界。实验结果表明,改进后的网络在有噪声的DDFF-12数据集上,相较于原始DFVDFF网络,均方误差下降了7.40%;在无噪声的FoD500数据集上,相较于原始DFVDFF网络,均方误差下降了19.07%。并且,改进后的网络在两个数据集上生成的深度图比DFVDFF网络生成的深度图具有更清晰的纹理边界。 展开更多
关键词 深度学习 变焦深度测量 DFVDFF 结构相似度 损失函数
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基于Simhash算法的题库查重系统的设计与实现
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作者 熊良钰 邓伦丹 《科学技术创新》 2024年第9期91-94,共4页
Simhash算法是一种基于局部敏感哈希(LSH)的技术,以其快速的计算速度和高度的查重准确性而知名。该算法通过将文本特征转换为二进制码,进而通过计算这些二进制码之间的汉明距离来评估文本的相似度。在文本去重和重复文档检测等多个领域,... Simhash算法是一种基于局部敏感哈希(LSH)的技术,以其快速的计算速度和高度的查重准确性而知名。该算法通过将文本特征转换为二进制码,进而通过计算这些二进制码之间的汉明距离来评估文本的相似度。在文本去重和重复文档检测等多个领域,Simhash算法已经展现出了显著的效果。鉴于此,将Simhash算法应用于题库查重具有很高的可行性和实际应用价值。 展开更多
关键词 Simhash算法 汉明距离 题库查重系统 文本相似度计算 哈希函数
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南亚热带森林不同林型功能性状分布格局及其驱动机制
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作者 周景钢 李林 +2 位作者 魏识广 练琚愉 叶万辉 《热带亚热带植物学报》 CAS CSCD 北大核心 2024年第2期187-197,共11页
植物功能性状能反映植物对环境变化的响应,研究植物功能性状的分布格局有助于揭示群落的构建过程及其内在作用机制。该研究以鼎湖山南亚热带山地常绿阔叶林和沟谷雨林为研究对象,采集并测量了样地中木本植物的12种不同的功能性状,分别以... 植物功能性状能反映植物对环境变化的响应,研究植物功能性状的分布格局有助于揭示群落的构建过程及其内在作用机制。该研究以鼎湖山南亚热带山地常绿阔叶林和沟谷雨林为研究对象,采集并测量了样地中木本植物的12种不同的功能性状,分别以5 m×5 m、10 m×10 m、20 m×20 m的样方为尺度单元,通过计算平均成对性状距离指数来探讨群落中功能性状的分布格局及其驱动机制。结果表明,两个林型的群落中12个功能性状均存在不同程度变异,但功能性状在群落间的差异不显著(P>0.05)。两个林型的群落中功能性状空间分布格局均具有尺度依赖性,但不同尺度的驱动机制有差异,随着空间尺度的增大,山地常绿阔叶林的功能性状空间分布格局主要驱动机制由环境过滤转为扩散限制;沟谷雨林的由环境过滤和相似性限制转为扩散限制,两个林型在20m×20m空间尺度上都是扩散限制。生态位分化和扩散限制综合作用于鼎湖山南亚热带山地常绿阔叶林和沟谷雨林的群落功能性状分布格局的产生及其群落构建过程,二者的贡献作用会随空间尺度发生变化。坡度是影响山地常绿阔叶林功能性状分布格局的最关键地形因子,海拔是影响沟谷雨林的最关键地形因子。 展开更多
关键词 功能性状 分布格局 环境过滤 相似性限制 扩散限制
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