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基于偏微分方程的新的图像去噪模型

南京邮电大学学报（自然科学版） 2019年第2期39卷 13-19页

作者：闵莉花李振华冯灿朱铭锋南京邮电大学理学院江苏南京210023 北方信息控制研究院集团有限公司江苏南京211153

针对二阶偏微分方程处理含噪声图像时存在的阶梯效应,文中提出了一个新的四阶偏微分方程图像去噪模型。首先对提出的模型利用有限差分法进行数值计算,然后分别对Lena图像、Cameraman图像和彩色Lena图像、彩色Peppers图像进行MATLAB仿真... 详细信息

针对二阶偏微分方程处理含噪声图像时存在的阶梯效应,文中提出了一个新的四阶偏微分方程图像去噪模型。首先对提出的模型利用有限差分法进行数值计算,然后分别对Lena图像、Cameraman图像和彩色Lena图像、彩色Peppers图像进行MATLAB仿真实验,将文中提出的模型与已有的去噪模型进行比较,分析结果表明文中提出的新模型能有效去除乘性噪声。

关键词：图像去噪偏微分方程有限差分法 MATLAB

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太阳黑子手绘图快速背景提取方法

国外电子测量技术 2018年第1期37卷 122-127页

作者：舒瑶朱明锋三峡大学理学院

太阳黑子手绘图是记录太阳黑子活动的传统方式,手绘图的数字化有利于数据的长期保存和研究,而背景提取是数字化过程中的一个关键问题。针对该问题,提出了一种基于Lab色彩空间的快速背景提取方法。首先,在Lab色彩空间中,对手绘图的a、b... 详细信息

太阳黑子手绘图是记录太阳黑子活动的传统方式,手绘图的数字化有利于数据的长期保存和研究,而背景提取是数字化过程中的一个关键问题。针对该问题,提出了一种基于Lab色彩空间的快速背景提取方法。首先,在Lab色彩空间中,对手绘图的a、b色彩分量进行K-means聚类。聚类结果表明,背景部分与手绘部分准确的分割为两类。对于大批量手绘图背景提取的情况,为加快提取速度,仅随机抽取部分手绘图进行聚类,再根据样本的聚类结果,运用最近质心分类器对其他手绘图进行背景提取。实验结果表明,此方法在保证提取准确性的前提下,极大地加快了提取速度,具有很好的鲁棒性。

关键词：背景提取太阳黑子 Lab色彩空间 K-means聚类最近质心分类器

Stabilities of delay stochastic McKean-Vlasov equations in the G-framework

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Science China(Information Sciences) 2025年第1期68卷 255-277页

作者： Haiyan YUAN Quanxin zhu Department of Mathematics Heilongjiang Institute of Technology Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and Statistics Hunan Normal University

This article focuses on a type of stochastic Mc Kean-Vlasov equation in the G-framework(G-SMVE) and addresses the stability issue for delay stochastic Mc Kean-Vlasov equations in the G-framework(G-SMVDEs). Distribution dependence and uncertainty prevent us from directly applying the stochastic analysis method for stochastic Mc Kean-Vlasov equations(SMVEs)to G-SMVEs directly. To overcome this difficulty, we introduce definitions, including the derivative of a function with a law under the G-expectation and the Lions derivatives. Then we construct a new G-It? formula for G-SMVEs according to the G-It? formula for stochastic differential equations in the G-framework(G-SDEs) and the It? formula for SMVEs. Using the new G-It? formula and the Lyapunov functional method, we investigate the moment exponential stability and almost sure asymptotic stability of G-SMVDEs. To overcome the difficulty in obtaining the distribution dependence of the exact solution to the G-SMVDE, we introduce the empirical measure and the corresponding interacting particle system, and then prove the stability equivalence between the underlying G-SMVDE and the corresponding interacting particle system. Two examples are used to confirm our theoretical results.

关键词： delay stochastic McKean-Vlasov equations Wasserstein distance G-Brownian motion Lions derivative stability

“Slope-adsorption&plateau-pore filling”mechanism unlocking the potential of hard carbon anodes for“fast-charging&large-sized”batteries

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Science China Materials 2025年第1期68卷 309-311页

作者： Tian Liang Xiaoming zhu Hubei Key Laboratory of Radiation Chemistry and Functional Materials School of Nuclear Technology and Chemistry&BiologyHubei University of Science and TechnologyXianning 437100China

To date,there has been no report on fast-charging and Ahlevel sodium-ion batteries(SIBs)by utilizing thick hard carbon anodes that demonstrate prolonged cycling life and high areal capacity at high ***,the relationship among the complex structure of hard carbon,storage mechanism,and fastcharging performance in alkali-metal ion batteries has been a subject of ongoing debate[1,2].

关键词： mechanism charging utilizing

重复异位妊娠危险因素及甲氨蝶呤治疗重复与首次异位妊娠结局的分析

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中国医药科学 2023年第20期13卷 70-73页

作者：朱明凤陶群安徽医科大学附属巢湖医院妇产科安徽合肥238000

目的探讨重复异位妊娠(REP)发生的相关危险因素以及单剂量甲氨蝶呤(MTX)对REP和首次异位妊娠(PEP)患者治疗结局的分析。方法选取2016年1月至2022年1月于安徽医科大学附属巢湖医院住院并接受单剂量MTX治疗的143例输卵管妊娠患者为研究对... 详细信息

目的探讨重复异位妊娠(REP)发生的相关危险因素以及单剂量甲氨蝶呤(MTX)对REP和首次异位妊娠(PEP)患者治疗结局的分析。方法选取2016年1月至2022年1月于安徽医科大学附属巢湖医院住院并接受单剂量MTX治疗的143例输卵管妊娠患者为研究对象,根据异位妊娠(EP)的次数分为REP组(n=42)和PEP组(n=101),采用logistic回归分析方法对REP的相关危险因素进行分析。结果单因素分析结果显示,REP的发生与流产次数、盆腔炎症史、既往盆腔手术史有关,差异有统计学意义(P0.05)。多因素分析结果显示,流产次数≥2次、既往盆腔手术史是REP发生的独立危险因素(P<0.05)。REP组的单剂量MTX治疗成功率明显低于PEP组(59.52%vs.77.23%),差异有统计学意义(P<0.05)。结论流产次数≥2次、既往盆腔手术史是REP发生的独立危险因素。在REP病例中,单剂量MTX方案的治疗成功率低于预期,提示在这种情况下应考虑不同的治疗方法。

关键词：重复异位妊娠危险因素甲氨蝶呤异位妊娠

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Chemical weathering in Manas River Basin:Driven by sulfuric acid or carbonic acid?

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Acta Geochimica 2025年第1期44卷 59-85页

作者： Jiaxin Zhang Bingqi zhu Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Carbonic acid produced by the dissolution of atmospheric and soil CO_(2)in water is usually the most dominant catalyst for chemical weathering,but a sulfuric aciddriven phenomenon,different from usual,was found in the orogenic belt watersheds dominated by silicate *** study,rooted in comprehensive field investigations in the Manas River Basin(MRB)north of the Tianshan Mountains,delves into the mechanisms and impacts of sulfuric and carbonic acid as catalysts driving diff erent types of chemical weathering in the Central Asian Orogenic *** analyses elucidate that carbonate weathering constitutes 52.4%of the total chemical weathering,while silicate and evaporite account for 18.6%and 25.3%,respectively,with anthropogenic activities and atmospheric precipitation having little eff *** estimated total chemical weathering rate in MRB is approximately 0.075×10^(6)mol/km^(2)/*** findings further suggest that,preceding carbonate precipitation(<10^(4)year),chemical weathering can absorb CO_(2).Subsequently,and following carbonate precipitation(10^(4)-10^(7)year),it will release CO_(2).The release significantly surpasses the global average CO_(2)consumption,contributing to a noteworthy climate *** study underscores the distinctive weathering mechanisms,wherein sulfuric acid emerges as the predominant *** quantity of sulfuric acid as a catalyst is approximately three times that of carbonic *** acid-driven carbonate rock weathering(SCW)is identified as the sole chemical weathering type with a net CO_(2)release eff *** CO_(2)release flux(5176 mol/km^(2)/year)is roughly 2.5 times the CO_(2)absorption by Ca-Mg silicate weathering,highlighting the pivotal role of chemical weathering in sourcing atmospheric CO_(2)over the timescales of carbonate precipitation and sulfate ***,this study posits that catalyst and transport limitations are the most plausible critical factors in *** interplay between s

关键词： Catchment chemical weathering Mid-latitude orogenic belt Sulﬁde oxidation Manas River Basin

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基于网络关系的微博水军集团发现方法

计算机工程与应用 2017年第6期53卷 96-100页

作者：叶施仁叶仁明朱明峰常州大学信息科学与工程学院江苏常州213164

由于目前水军的高伪装性,经典的水军识别算法变得不再有效。与真实用户相同,水军用户之间也会形成一定的网络结构,提出了一种基于网络关系的方法来发现水军集团,首先以一个典型的水军账号作为种子,逐层扩展粉丝关系,优先搜索出现次数频... 详细信息

由于目前水军的高伪装性,经典的水军识别算法变得不再有效。与真实用户相同,水军用户之间也会形成一定的网络结构,提出了一种基于网络关系的方法来发现水军集团,首先以一个典型的水军账号作为种子,逐层扩展粉丝关系,优先搜索出现次数频繁的用户,从而获得一个包含大量水军账号的集合,按照水军用户之间关系的高度聚集性以及与真实用户之间关系稀疏性的特点,用Fast Unfolding算法进行社区检测。实验结果表明,该方法能够很好地发现水军集团。

关键词：水军集团网络关系社区检测

A water probe for direct pH measurement of individual particles via micro-Raman spectroscopy

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Journal of Environmental Sciences 2025年第3期149卷 200-208页

作者： Xiaoyu Cui Mingjin Tang Tong zhu School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China BIC-ESAT and SKL-ESPC College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The acidity of atmospheric aerosols influences fundamental physicochemical processes that affect climate and human *** recently developed a novel and facilewater-probebased method for directly measuring of the pH for micrometer-size droplets,providing a promising technique to better understand aerosol acidity in the *** complex chemical composition of fine particles in the ambient air,however,poses certain challenges to using a water-probe for pH measurement,including interference from interactions between compositions and the influence of similar compositions on water *** explore the universality of our method,it was employed to measure the pH of ammonium,nitrate,carbonate,sulfate,and chloride *** pH of particles covering a broad range(0–14)were accurately determined,thereby demonstrating that our method can be generally applied,even to alkaline ***,a standard spectral library was developed by integrating the standard spectra of common hydrated ions extracted through the *** library can be employed to identify particle composition and overcome the spectral overlap problem resulting from similar *** the spectral library,all ions were identified and their concentrations were determined,in turn allowing successful pH measurement of multicomponent(ammonium-sulfate-nitrate-chloride)*** into the synergistic effect of Cl^(–),NO_(3)^(–),and NH_(4)^(+)depletion obtained with our approach revealed the interplay between pH and volatile *** the ubiquity of component partitioning and pH variation in particles,the water probemay provide a new perspective on the underlying mechanisms of aerosol aging and aerosol–cloud interaction.

关键词： Particle pH Water probe Standard spectral library Micro-Raman spectroscopy Direct measurement

Effect of Parameter Variation in the BMJ Scheme on the Simulation of MJO Propagation and Structure

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Advances in Atmospheric Sciences 2025年第2期42卷 397-409页

作者： Xiaoyu zhu Zhong ZHONG Yimin zhu Yunying LI Yijia HU Yao HA College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In this study,the Betts-Miller-Janjic(BMJ)convective adjustment scheme in the Weather Research and Forecasting(WRF)model version 4.0 was used to investigate the effect of itsα-parameter,which influences the first-guess potential temperature reference profile on the Madden-Julian oscillation(MJO)propagation and *** study diagnosed the MJO active phase composites of the MJO-filtered outgoing longwave radiation(OLR)during the December-to-February(DJF)period of 2006-2016 over the Indian Ocean(IO),Maritime Continent(MC),and western Pacific(WP).The results show that the MJO-filtered OLR intensity,propagation pattern,and MJO classification(standing,jumping,and propagating clusters)are sensitive to theα-value,but the phase speeds of propagating MJOs are ***,with an increasingα-value,the simulated MJO-filtered OLR intensity increases,and the simulated propagation pattern is *** also show that the intensity and propagation pattern of an eastward-propagating MJO are associated with MJO circulation structures and thermodynamic ***αincreases,the front Walker cell and the low-level easterly anomaly are enhanced,which premoistens the lower troposphere and triggers more active shallow and congestus *** enhanced shallow and congestus convection preconditions the lower to middle troposphere,accelerating the transition from congestus to deep convection,thereby facilitating eastward propagation of the ***,the simulated MJO tends to transfer from standing to eastward propagating asα*** summary,increasing theα-value is a possible way to improve the simulation of the structure and propagation of the MJO.

关键词： MJO WRF model BMJ scheme low-level easterly anomaly