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Learning Laws for Deep Convolutional Neural Networks With Guaranteed Convergence
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作者 Sitan Li Chien Chern Cheah 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期170-185,共16页
Convolutional neural networks(CNNs)have shown remarkable success across numerous tasks such as image classification,yet the theoretical understanding of their convergence remains underdeveloped compared to their empir... Convolutional neural networks(CNNs)have shown remarkable success across numerous tasks such as image classification,yet the theoretical understanding of their convergence remains underdeveloped compared to their empirical achievements.In this paper,the first filter learning framework with convergence-guaranteed learning laws for end-to-end learning of deep CNNs is proposed.Novel update laws with convergence analysis are formulated based on the mathematical representation of each layer in convolutional neural networks.The proposed learning laws enable concurrent updates of weights across all layers of the deep convolutional neural network and the analysis shows that the training errors converge to certain bounds which are dependent on the approximation errors.Case studies are conducted on benchmark datasets and the results show that the proposed concurrent filter learning framework guarantees the convergence and offers more consistent and reliable results during training with a trade-off in performance compared to stochastic gradient descent methods.This framework represents a significant step towards enhancing the reliability and effectiveness of deep convolutional neural network by developing a theoretical analysis which allows practical implementation of the learning laws with automatic tuning of the learning rate to guarantee the convergence during training. 展开更多
关键词 convergence convolution neural networks(CNNs) end-to-end learning online learning
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Revealing the potential geographic convergence of global water scarcity risk and virtual water trade inequality:A three-module integrated analytical approach
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作者 Qiting Zuo Zhizhuo Zhang +2 位作者 Junxia Ma Qingsong Wu Yihu Ji 《Geography and Sustainability》 2026年第1期141-154,共14页
Unequal virtual water transfer may aggravate local water scarcity risk.However,the quantitative confirmation of a clear geographic convergence between virtual water transfer and water scarcity risk remains undetermine... Unequal virtual water transfer may aggravate local water scarcity risk.However,the quantitative confirmation of a clear geographic convergence between virtual water transfer and water scarcity risk remains undetermined.We present an analytical framework that reveals the spatial matching between global water scarcity risk and virtual water trade inequality.This framework integrates a three-dimensional water scarcity risk assessment,hybrid input-output analysis,pollution trade term construction,and geographic convergence identification.The framework is applied to 123 countries for long-term validation from 1991 to 2021.We show that despite global improvements in water efficiency and security,countries exceeding the maximum water vulnerability threshold have increased by 50%.South Asia is the largest net exporter of virtual water.Central Asia exhibits the most pronounced virtual water trade inequality.To achieve the same economic growth,Central Asia needs to pay several times the local water consumption costs of developed regions(15.9−83.6 times,2021).In the past 30 years,the average geographic convergence index exceeded 0.8.Countries facing severe water scarcity also exhibit pronounced inequalities in virtual water trade,indicating that a significant geographic convergence relationship exists.Effectively responding to this unsustainable relationship necessitates balancing both domestic resource risk management and global virtual water trade regulation. 展开更多
关键词 Water scarcity risk Virtual water transfer Global inequity Geographic convergence Water resources management
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Biodiversity and biogeographic patterns of Nereididae(Annelida)across the Indo-Pacific Convergence Zone
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作者 Jieyang WENG Xuwen WU +2 位作者 Tiantian WANG Chenrui LI Linlin ZHANG 《Journal of Oceanology and Limnology》 2026年第1期322-339,共18页
Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the un... Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the understanding of biodiversity and biogeography of Nereididae in the IPCZ,we integrated historical data of species distributions with those of model-predicted ones to determine the biogeographic patterns of nereid species,from which we projected to its future distribution patterns for 2090-2100 under different climate scenarios(SSP1-1.9 and SSP5-8.5).Functional diversity within IPCZ was assessed using functional richness,functional evenness,and functional disparity.Divergence times within Nereididae were estimated using three DNA marker genes(COI,16S,and 18S rRNA),and a time tree was constructed based on a strict molecular clock model.The IPCZ was established as a key Nereididae biodiversity hotspot through distribution modelling of 256 species(44 genera),and temperature emerging as the predominant climatic driver of species distribution patterns.The distribution of species and functional diversity is notable for its non-centralized pattern.We projected that by the end of the century,areas of medium-to-high species richness will expand significantly under the low-emission SSP1-1.9 climate scenario.However,under the high-emission SSP5-8.5 scenario,the suitability of these regions significantly declines,posing an increasingly severe threat to biodiversity.In addition,by molecular clock analysis,we revealed that the evolutionary divergence of extant nereidid species occurred mainly in the Cretaceous and Jurassic,suggesting that paleogeographical and environmental events,such as oceanic anoxic events,might have played a pivotal role in shaping the evolutionary trajectory and ecological adaptations of marine annelids.These findings highlight the importance of considering both current biodiversity patterns and historical contexts in conservation planning,and provided insights into the potential factors on the biogeographic distribution and evolutionary processes of Nereididae. 展开更多
关键词 NEREIDIDAE species distribution model(SDM) climate change BIODIVERSITY Indo-Pacific convergence Zone(IPCZ)
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A CLASS OF NONLINEAR THERMO-PIEZOELECTRIC CONTACT PROBLEM WITH COULOMB'S LAW:EXISTENCE,UNIQUENESS AND CONVERGENCE
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作者 Jinxia CEN Abdelhadi HACHLAF 《Acta Mathematica Scientia》 2026年第1期255-274,共20页
In this paper,we study a comprehensive mathematical model describing the problem of frictional contact between a nonlinear thermo-piezoelectric body and a rigid foundation with electrically conductive effect,in which ... In this paper,we study a comprehensive mathematical model describing the problem of frictional contact between a nonlinear thermo-piezoelectric body and a rigid foundation with electrically conductive effect,in which the contact conditions are described by a Signorini’s condition and Coulomb’s friction law.We derive the variational form of the contact problem which is a mixed system formulated by variational inequalities and equalities.Then,we use standard results on mixed problems and the Banach fixed-point theorem to prove the existence and uniqueness of the solution to the contact problem.Moreover,we demonstrate the convergence of a penalty method for this contact problem under consideration.Finally,finite element method is applied to the penalty contact problem and a strong convergence theorem is obtained. 展开更多
关键词 thermo-piezoelectric material Signorini’s condition mixed formulation existence and convergence penality method finite element method
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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Innovative Paths for Campus Media in the Context of Media Convergence
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作者 Feng Han Wenyun Zhao 《Journal of Contemporary Educational Research》 2025年第6期160-165,共6页
The rapid development of Internet technology has made“Internet+”a hallmark of the current era.The transformation and development of traditional media into all-media have provided a guiding direction for the developm... The rapid development of Internet technology has made“Internet+”a hallmark of the current era.The transformation and development of traditional media into all-media have provided a guiding direction for the development of campus media.The traditional form of campus media,which mainly consists of campus newspapers and campus radio,can no longer meet the application demands of modern higher education for media.In line with the current media convergence environment,campus media need to actively innovate to achieve their own development and progress in keeping with the times.This article explores the innovation path of campus media in the context of media convergence,analyzing the promotion of campus media innovation by the development of new media,the diversification of campus media innovation,and the effective ways of campus media innovation,in order to promote the realization of the innovation and development goals of campus media in the context of media convergence. 展开更多
关键词 Media convergence Campus media INNOVATION
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Exploring Economic Convergence Within the Silk Road Sphere:An Analysis of Central Asian Turkic Republics,China,Pakistan,and Key Diplomatic Allies
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作者 Abdul Wajid 《Management Studies》 2025年第3期135-146,共12页
This study looks at how the Belt and Road Initiative(BRI)has affected the economic convergence of the Central Asian Turkic Republics,China,Pakistan,and their major diplomatic partners in the Silk Road region.Using bet... This study looks at how the Belt and Road Initiative(BRI)has affected the economic convergence of the Central Asian Turkic Republics,China,Pakistan,and their major diplomatic partners in the Silk Road region.Using beta and sigma convergence models over a predetermined time frame,the research evaluates economic alignment trends statistically and looks into how trade openness,FDI,and human capital affect the convergence process.The research attempts to discover larger causes of convergence,such as institutional quality and geopolitical closeness,by combining econometric analysis with regional economic dynamics.The purpose of the results is to provide policy suggestions that will improve equitable and sustainable economic convergence inside the Silk Road circle,promoting international cooperation and growth. 展开更多
关键词 economic convergence Silk Road beta and sigma convergence models foreign direct investment(FDI) trade transparency human capital development
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Deterministic Convergence Analysis for GRU Networks via Smoothing Regularization
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作者 Qian Zhu Qian Kang +2 位作者 Tao Xu Dengxiu Yu Zhen Wang 《Computers, Materials & Continua》 2025年第5期1855-1879,共25页
In this study,we present a deterministic convergence analysis of Gated Recurrent Unit(GRU)networks enhanced by a smoothing L_(1)regularization technique.While GRU architectures effectively mitigate gradient vanishing/... In this study,we present a deterministic convergence analysis of Gated Recurrent Unit(GRU)networks enhanced by a smoothing L_(1)regularization technique.While GRU architectures effectively mitigate gradient vanishing/exploding issues in sequential modeling,they remain prone to overfitting,particularly under noisy or limited training data.Traditional L_(1)regularization,despite enforcing sparsity and accelerating optimization,introduces non-differentiable points in the error function,leading to oscillations during training.To address this,we propose a novel smoothing L_(1)regularization framework that replaces the non-differentiable absolute function with a quadratic approximation,ensuring gradient continuity and stabilizing the optimization landscape.Theoretically,we rigorously establish threekey properties of the resulting smoothing L_(1)-regularizedGRU(SL_(1)-GRU)model:(1)monotonic decrease of the error function across iterations,(2)weak convergence characterized by vanishing gradients as iterations approach infinity,and(3)strong convergence of network weights to fixed points under finite conditions.Comprehensive experiments on benchmark datasets-spanning function approximation,classification(KDD Cup 1999 Data,MNIST),and regression tasks(Boston Housing,Energy Efficiency)-demonstrate SL_(1)-GRUs superiority over baseline models(RNN,LSTM,GRU,L_(1)-GRU,L2-GRU).Empirical results reveal that SL_(1)-GRU achieves 1.0%-2.4%higher test accuracy in classification,7.8%-15.4%lower mean squared error in regression compared to unregularized GRU,while reducing training time by 8.7%-20.1%.These outcomes validate the method’s efficacy in balancing computational efficiency and generalization capability,and they strongly corroborate the theoretical calculations.The proposed framework not only resolves the non-differentiability challenge of L_(1)regularization but also provides a theoretical foundation for convergence guarantees in recurrent neural network training. 展开更多
关键词 Gated recurrent unit REGULARIZATION convergence
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阿利吉仑和缬沙坦对载脂蛋白E基因敲除小鼠动脉粥样硬化的影响
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作者 张辉 赵雨薇 +4 位作者 李勤 张洁钰 张彬彬 王蒙蒙 曹昶 《郑州大学学报(医学版)》 北大核心 2026年第1期71-74,共4页
目的:观察阿利吉仑和缬沙坦对载脂蛋白E基因敲除(apoE^(-/-))小鼠动脉粥样硬化(AS)的影响。方法:54只apoE^(-/-)小鼠高脂喂养并采用颈总动脉缩窄性套管法刺激AS形成。apoE^(-/-)小鼠随机分为阿利吉仑组(每天给予25 mg/kg)、缬沙坦组(每... 目的:观察阿利吉仑和缬沙坦对载脂蛋白E基因敲除(apoE^(-/-))小鼠动脉粥样硬化(AS)的影响。方法:54只apoE^(-/-)小鼠高脂喂养并采用颈总动脉缩窄性套管法刺激AS形成。apoE^(-/-)小鼠随机分为阿利吉仑组(每天给予25 mg/kg)、缬沙坦组(每天给予3 mg/kg)和对照组(给予安慰剂),每组18只。10周后处死小鼠,取静脉血采用ELISA法测定血浆肾素活性(PRA)、醛固酮、血脂、脂蛋白相关磷脂酶A 2(Lp-PLA 2)和单核细胞趋化蛋白-1(MCP-1)水平;取颈动脉斑块HE和油红O染色后测定斑块面积、纤维帽厚度及脂质含量;采用qRT-PCR检测斑块组织中Lp-PLA 2及MCP-1 mRNA的表达。结果:3组小鼠血脂水平比较,差异均无统计学意义(P>0.05)。阿利吉仑组和缬沙坦组斑块脂质含量低于对照组,纤维帽厚度大于对照组,斑块面积小于对照组(P<0.05)。与对照组比较,缬沙坦组PRA升高,醛固酮水平降低;与缬沙坦组比较,阿利吉仑组PRA和醛固酮水平降低(P<0.05)。与对照组比较,阿利吉仑组及缬沙坦组血浆Lp-PLA 2、MCP-1水平及斑块组织中二者mRNA表达水平降低;与缬沙坦组比较,阿利吉仑组上述指标降低(P<0.05)。结论:阿利吉仑可改善apoE^(-/-)小鼠AS,且该作用优于缬沙坦。 展开更多
关键词 阿利吉仑 缬沙坦 动脉粥样硬化 载脂蛋白E基因敲除小鼠
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Enriching harmonic balance with non‐smooth Bernoulli bases for accelerated convergence of non-smooth periodic systems
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作者 Yu Zhou Jianliang Huang Li Wang 《Theoretical & Applied Mechanics Letters》 2025年第1期57-68,共12页
The harmonic balance method(HBM)has been widely applied to get the periodic solution of nonlinear systems,however,its convergence rate as well as computation efficiency is dramatically degraded when the system is high... The harmonic balance method(HBM)has been widely applied to get the periodic solution of nonlinear systems,however,its convergence rate as well as computation efficiency is dramatically degraded when the system is highly non-smooth,e.g.,discontinuous.In order to accelerate the convergence,an enriched HBM is developed in this paper where the non-smooth Bernoulli bases are additionally introduced to enrich the conventional Fourier bases.The basic idea behind is that the convergence rate of the HB solution,as a truncated Fourier series,can be improved if the smoothness of the solution becomes finer.Along this line,using non-smooth Bernoulli bases can compensate the highly non-smooth part of the solution and then,the smoothness of the residual part for Fourier approximation is improved so as to achieve accelerated convergence.Numerical examples are conducted on systems with non-smooth restoring and/or external forces.The results confirm that the proposed enriched HBM indeed increases the convergence rate and the increase becomes more significant if more non-smooth bases are used. 展开更多
关键词 Harmonic balancemethod Non-smooth Bernoullibases Event-driven Gaussquadrature Non-smooth systems Accelerated convergence
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东北印度洋90°E海岭表层沉积物碳酸钙组成与影响因子
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作者 杜恕环 向荣 +5 位作者 苏翔 张兰兰 潘子锐 谢金沃 罗传秀 万随 《热带海洋学报》 北大核心 2026年第1期73-80,共8页
本研究针对东北印度洋90°E海岭区表层沉积物碳酸钙空间分异机制的科学问题,通过多尺度分析方法揭示其控制因素与生物地球化学过程。基于10个站位表层沉积物的全样及分粒级(>150μm、63~150μm、38~63μm、25~38μm、<25μm)... 本研究针对东北印度洋90°E海岭区表层沉积物碳酸钙空间分异机制的科学问题,通过多尺度分析方法揭示其控制因素与生物地球化学过程。基于10个站位表层沉积物的全样及分粒级(>150μm、63~150μm、38~63μm、25~38μm、<25μm)碳酸钙含量测试,结合扫描电镜显微特征定量统计,发现:(1)研究区碳酸钙含量呈现36.95%~74.76%的显著空间分异(均值56.05%),形成30%~45%、45%~60%、60%~75%三级梯度格局;(2)水深3000m以上区域,碳酸钙主控组分为>150μm浮游有孔虫壳体(占比>65%),而接近/超过溶跃面的站位则以<25μm细颗粒组分为主(贡献率>58%);(3)显微特征定量分析首次揭示25~38μm组分中钙质沟鞭藻化石(相对丰度最高达73.68%)与超微化石、有孔虫碎片的协同沉积模式。进一步研究表明,碳酸钙分布主要由三元调控机制主导,即水深控制的溶解效应、陆源碎屑输入和硅质生物稀释作用。本研究创新性地建立了“粒级分离-显微统计-环境解译”的综合研究方法。该方法不仅完善了海山地貌单元碳酸钙分布理论模型,其发现的钙质沟鞭藻新碳源类型也拓展了对深海无机碳库的组成认知。研究成果可为全球海岭区碳酸钙保存机制的对比研究提供关键案例,并通过改进粒径特异性碳酸钙通量算法,为海洋碳循环模型参数化提供重要科学依据。 展开更多
关键词 90°E海岭 表层沉积物 碳酸钙组成 分粒级碳酸钙
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The Convergence Analyzed by Stochastic C-Stability and Stochastic B-Consistency of Split-Step Theta Method for the Stochastic Differential Equations
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作者 Ping GUO Ye WANG Yining GAO 《Journal of Mathematical Research with Applications》 2025年第3期362-376,共15页
In this paper,the convergence of the split-step theta method for stochastic differential equations is analyzed using stochastic C-stability and stochastic B-consistency.The fact that the numerical scheme,which is both... In this paper,the convergence of the split-step theta method for stochastic differential equations is analyzed using stochastic C-stability and stochastic B-consistency.The fact that the numerical scheme,which is both stochastically C-stable and stochastically B-consistent,is convergent has been proved in a previous paper.In order to analyze the convergence of the split-step theta method(θ∈[1/2,1]),the stochastic C-stability and stochastic B-consistency under the condition of global monotonicity have been researched,and the rate of convergence 1/2 has been explored in this paper.It can be seen that the convergence does not require the drift function should satisfy the linear growth condition whenθ=1/2 Furthermore,the rate of the convergence of the split-step scheme for stochastic differential equations with additive noise has been researched and found to be 1.Finally,an example is given to illustrate the convergence with the theoretical results. 展开更多
关键词 stochastic differential equation stochastic C-stability stochastic B-consistency convergence split-step theta method
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Constructing the Discursive Framework of Chinese Journalistic Narrative within Media Convergence Contexts:A Review on Liu Tao's Narrative of Convergent Journalism:Story,Language and Rhetoric
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作者 Tang Li 《符号与传媒》 2025年第2期259-274,共16页
Convergent journalism constitutes a systematic investigation into emergent journalistic forms,conceptual frameworks,and practices emerging within media convergence context,characterized by its inherent attributes of c... Convergent journalism constitutes a systematic investigation into emergent journalistic forms,conceptual frameworks,and practices emerging within media convergence context,characterized by its inherent attributes of convergence,datacentricity,and interactivity.Grounded in the theoretical discourse of digital narratology,this monograph crystallizes its analytical focus on the triadic conceptual constellation of"convergence""mediaticity"and"narrativity",By positioning""convergence"as the central problematique,it systematically constructs an epistemological framework for convergent journalistic narrative through three dimensions:narrative theory,narrative language,and narrative praxis,thereby elucidates the ontological foundations and operational logics intrinsic to contemporary journalism studies. 展开更多
关键词 narrativity narrative praxis digital narratology convergent journalism narrative language mediaticity narrative theory
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Complete q-Order Moment Convergence of Moving Average Processes Generated by Negatively Dependent Random Variables under Sub-Linear Expectations
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作者 Mingzhou XU 《Journal of Mathematical Research with Applications》 2025年第3期395-410,共16页
Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+... Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+n),n≥1}under some proper conditions,where{Yi,-∞<i<∞}is a doubly infinite sequence of negatively dependent random variables under sub-linear expectations.These results extend and complement the relevant results in probability space. 展开更多
关键词 moving average processes negatively dependent random variables complete moment convergence sub-linear expectations
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Etiquette and Customs Interaction and Media Convergence in Huizhou:A Perspective on Rural Cultural Revitalization
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作者 ZHAO Xin DENG Yuanyuan 《Journal of Landscape Research》 2025年第5期61-64,共4页
Huizhou etiquette and customs culture,as a significant element of China’s rural cultural system that integrates ethical profundity with the warmth of everyday life,embodies the collective memory and cultural identity... Huizhou etiquette and customs culture,as a significant element of China’s rural cultural system that integrates ethical profundity with the warmth of everyday life,embodies the collective memory and cultural identity of the regional community.In the context of social transformation characterized by informatization and globalization,the social structures and spatial domains that underpin traditional etiquette and customs are undergoing disruption.Focusing on Huizhou region as a case study,this paper investigates the transmission mechanisms and paths of identity reconstruction associated with etiquette and customs culture within the framework of media convergence.The research is conducted at three levels.First,at the symbolic catalyst level,the refinement of symbols and contextual translation facilitate the dynamic regeneration of Huizhou etiquette and customs symbols and reactivation of cultural significance.Second,at the media dimension level,a multi-dimensional communication system encompassing“the digital,social,and community layers”is constructed.Third,at the field identity level,the study analyzes how media convergence reorganizes material,social,and spiritual spaces to promote the reshaping of cultural identity among individuals and communities.Research indicates that the integration of digitalization,interactivity,and spatialization has transformed Huizhou etiquette and customs from static cultural heritage into a dynamic identity system,thereby facilitating a cultural cycle that“originating from the people and returning to the people”. 展开更多
关键词 Huizhou etiquette and customs Media convergence Symbolic catalyst Cultural identity Rural revitalization
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鸭坦布苏病毒E蛋白结构域Ⅲ抗体间接ELISA检测方法的建立与应用
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作者 曲哲会 张孟云 +7 位作者 陈晶晶 聂雅诺 王凤瑞 刘志科 焦凤超 郝香琪 梁成成 郭晓秋 《中国畜牧兽医》 北大核心 2026年第4期2082-2092,共11页
【目的】建立鸭坦布苏病毒(DTMUV)E蛋白结构域Ⅲ(E-DⅢ)抗体间接ELISA检测方法,为DTMUV血清学监测提供一种检测手段。【方法】利用PCR扩增DTMUV E-DⅢ基因,连接至pET-30a(+)载体构建重组质粒pET-E-DⅢ,转化大肠杆菌Rosetta(DE3)感受态细... 【目的】建立鸭坦布苏病毒(DTMUV)E蛋白结构域Ⅲ(E-DⅢ)抗体间接ELISA检测方法,为DTMUV血清学监测提供一种检测手段。【方法】利用PCR扩增DTMUV E-DⅢ基因,连接至pET-30a(+)载体构建重组质粒pET-E-DⅢ,转化大肠杆菌Rosetta(DE3)感受态细胞,经IPTG诱导后,SDS-PAGE和Western blotting鉴定表达产物,建立E-DⅢ蛋白抗体间接ELISA检测方法,优化抗原浓度和抗体稀释度、封闭条件、待检血清反应条件、酶标二抗反应条件和显色时间,明确临界值判断标准,评价所建立抗体间接ELISA检测方法的特异性、敏感性和重复性,并对背景清楚的126份血清进行检测。【结果】成功构建含大小约300 bp目的条带的重组质粒pET-E-DⅢ,诱导表达获得分子质量约16 ku的重组蛋白E-DⅢ,且以可溶性和包涵体共存表达,浓度为284.5 mg/L。经筛选确定最佳间接ELISA工作条件为:E-DⅢ蛋白包被浓度为250 ng/mL,待检血清稀释度为1∶80,封闭条件为25℃封闭1.5 h,待检血清反应条件为37℃孵育1 h,酶标二抗为1∶7500稀释,37℃孵育1 h,显色时间为10 min。确定D_(450nm)值≥0.337为阳性,D_(450nm)值≤0.282为阴性。特异性试验结果显示,该方法仅DTMUV阳性血清检测结果为阳性,新城疫病毒、H9亚型禽流感病毒、鸭瘟病毒、鸭肝炎病毒1型和3型阳性血清检测结果均为阴性。敏感性试验结果显示,该方法检测阳性血清的最大稀释度为1∶1280。重复性试验结果显示,批内试验和批间试验变异系数分别为2.11%~5.09%和3.25%~6.95%。126份背景清楚血清检测结果显示,阳性和阴性血清符合率分别为95.83%和96.30%。【结论】本研究表达纯化了DTMUV E-DⅢ蛋白,并成功建立了基于E-DⅢ蛋白的特异性好、敏感性高、重复性良好的抗体间接ELISA检测方法。 展开更多
关键词 鸭坦布苏病毒(DTMUV) E蛋白结构域Ⅲ 原核表达 间接ELISA 抗体
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High-entropy strategy in designing La_(2)Bi_(4)Cu_(2)O_(6)Se_(4)superlattice thermoelectric material with band convergence and low thermal conductivity
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作者 Peng Ai Shuwei Tang +6 位作者 Shulin Bai Da Wan Wanrong Guo Pengfei Zhang Tuo Zheng Hao Wang Tengyue Yan 《Journal of Energy Chemistry》 2025年第8期376-385,共10页
Designing novel van der Waals layered materials with low thermal conductivity and large power factor is important for the development of layered thermoelectric materials.Therefore,the novel van der Waals intercalated ... Designing novel van der Waals layered materials with low thermal conductivity and large power factor is important for the development of layered thermoelectric materials.Therefore,the novel van der Waals intercalated compound La_(2)Bi_(4)Cu_(2)O_(6)Se_(4),which is constructed by alternately stacking LaCuSeO and Bi_(2)O_(2)Se units along the c-axis in a 1:2 ratio,has designed for thermoelectric materials.The unique intercalated strategy leads to the four-band convergence at the valence band maximum,and the combination of multiple heavy band and light band,which significantly enhances the p-type doping power factor.The lattice thermal conductivities in La_(2)Bi_(4)Cu_(2)O_(6)Se_(4)and LaCuSeO compounds are accurately calculated by considering the coherence contributions of the anharmonic phonon reformulations and the off-diagonal term of the heat flux operator.The weak bond property of the Cu d-Se p bonding causes phonon softening,reducing the lattice thermal conductivity.The intercalated Bi atom has stereochemically active lone-pair electrons,which causes acoustic-optical coupling and produces strong fourth acoustic-optical phonon scattering,suppressing low-frequency phonon transport.The carrier relaxation time is rationalized by considering multiple carrier scattering mechanisms.The p-type doping La_(2)Bi_(4)Cu_(2)O_(6)Se_(4)achieves an average ZT of 2.3 at 700 K,and an optimal ZT of 2.7 along the in-plane direction.Our current work not only reveals the origin of the strong phonon scattering and large power factor of La_(2)Bi_(4)Cu_(2)O_(6)Se_(4)compound,but also provides theoretical guidance for the design of La-based layered oxides for thermoelectric applications. 展开更多
关键词 Superlattice material High-entropy strategy Band convergence Lone-pair electrons Acoustic-optical(A-O)phonon scattering
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Analysis of Business Model Innovation Strategies for the Convergence Development of Professional Publishing:A Case Study of Chinese People’s Health Press
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作者 WANG Jun XUE Yanting 《Cultural and Religious Studies》 2025年第1期33-41,共9页
This paper,grounded in the theory of business model innovation,examines the Chinese People’s Health Press(人民卫生出版社)as a case study to explore strategies for innovating business models within the context of prof... This paper,grounded in the theory of business model innovation,examines the Chinese People’s Health Press(人民卫生出版社)as a case study to explore strategies for innovating business models within the context of professional publishing convergence development.The research posits that effective business model innovation in this domain necessitates a comprehensive reform of its constituent elements.It advocates for a systematic approach to reconstructing value propositions,enhancing value creation and delivery processes,and optimizing value capture mechanisms to achieve desired outcomes. 展开更多
关键词 professional publishing convergence development business model innovation Chinese People’s Health Press
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Assessing the Convergence of Cropland Ecological Balance:A Panel Data Analysis of 13 Major Agricultural Countries
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作者 Orhan Simsek İlkay Güler +2 位作者 Sefa Ozbek Mustafa Naimoglu Zafer Adali 《Journal of Environmental & Earth Sciences》 2025年第7期16-34,共19页
This study investigates the convergence hypothesis and stochastic dynamics of agricultural land use and ecological balance across 13 major agricultural countries from 1992 to 2022.The study's concentrated samples ... This study investigates the convergence hypothesis and stochastic dynamics of agricultural land use and ecological balance across 13 major agricultural countries from 1992 to 2022.The study's concentrated samples are Russia,the United States,the Netherlands,Brazil,Germany,China,France,Spain,Italy,Canada,Belgium,Indonesia,and India.The research uncovers notable variations in ecological balance by utilizing a comprehensive set of advanced panel unit root tests(Panel CIPS,CADF,Panel-LM,Panel-KPSS,and Bahmani-Oskooee et al.’s Panel KPSS Unit Root Test).The findings highlight significant improvements in Canada,contrasting with declines in the Netherlands,France,Germany,and the United States.The results indicate convergence in ecological balance among these countries,suggesting that agricultural practices are progressively aligning with sustainability objectives.The considered countries can determine and enact joint and collective policy actions addressing cropland sustainability.However,the univariate outcome also shows that the cropland ecological balance of Germany,China,France,Indonesia,and India does contain a unit root and stationary which means the presence of the constant-mean.The univariate actions from the mentioned governments will not promote persistent impact.Therefore,joint actions determined by the countries considered are recommended for the mentioned countries.However,the rest of the countries also enact local policies.The insights gained are critical for informing global sustainability strategies and aiding policymakers in developing effective measures to enhance agricultural practices and mitigate environmental impacts.This research provides a data-driven foundation for optimizing agricultural sustainability and supports international efforts to achieve long-term ecological stability. 展开更多
关键词 Agricultural Land Use Ecological Balance convergence Hypothesis Stochastic Dynamics Panel Unit Root Tests Sustainable Development
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