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Strong Laws of Large Numbers for Sequences of Blockwise m-Dependent and Sub-Orthogonal Random Variables under Sublinear Expectations 被引量:1
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作者 Jialiang FU 《Journal of Mathematical Research with Applications》 2026年第1期103-118,共16页
In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random vari... In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random variables,and another is for sub-orthogonal random variables.Both extend the strong law of large numbers for independent random variables under sublinear expectations to the non-independent case. 展开更多
关键词 sublinear expectations strong law of large numbers blockwise m-dependent suborthogonal random variables
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High Throughput Random Access:Sign-Compute Diversity Slotted ALOHA
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作者 Xu Yu Wang Zhenyong +1 位作者 Cui Chen Guo Qing 《China Communications》 2026年第1期81-91,共11页
In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and m... In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and multiple user detection techniques,our scheme can reach a high throughput of 0.98 without feedback under finite frame size settings,where the upper bound on performance is 1.Moreover,a lower bound on throughput performance is derived,which is tight in some parameter settings and can be used to approximate theoretical performance.Simulation results validate our analysis and confirm the advantages of our proposed scheme. 展开更多
关键词 compute-and-forward diversity transmission random access slotted ALOHA THROUGHPUT
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Causal effect of obesity on cataract and mediating roles of metabolites:a Mendelian randomization study
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作者 Chen Li Jiao-Man Wang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 2026年第3期564-574,共11页
AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide asso... AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide association studies to examine the relationship between obesity and cataract were utilized.Obesity-related traits,including body mass index(BMI),waist-to-hip ratio(WHR),and waist circumference(WC).A two-sample MR approach was employed to assess the causal effect of obesity on cataract risk,while potential mediators were identified from suitable genome-wide association studies(GWAS)datasets.Additionally,a metabolic pathway analysis was conducted.RESULTS:An increase of 1 standard deviation(SD)in BMI,WHR,and WC was associated with a significantly higher risk of cataract(BMI:odds ratio(OR)1.0017,95%confidence interval(CI):1.0001-1.0032,P=0.0320;WHR:OR 1.0029,95%CI:1.0006-1.0051,P=0.0129;WC:OR 1.0020,95%CI:1.0001-1.0038,P=0.0390].These associations remained robust after adjusting for confounding factors in multivariable MR analysis.Furthermore,a two-step MR analysis identified eight potential metabolic mediators,with one mediator showing a significant causal role in the relationship between obesity and cataract.CONCLUSION:This work highlights the importance of addressing obesity as a modifiable risk factor for cataracts,particularly through metabolic pathways. 展开更多
关键词 OBESITY CATARACT Mendelian randomization body mass index waist-to-hip ratio waist circumference
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A Bidirectional Mendelian Randomization Study on the Causal Association between Psoriasis and Psychiatric Disorders
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作者 Bingting LI Xuefeng LI 《Medicinal Plant》 2026年第1期57-60,共4页
[Objectives]To investigate the potential causal relationship between psoriasis and common mental disorders,and to provide genetic epidemiological evidence for the early intervention of mental comorbidities.[Methods]Ba... [Objectives]To investigate the potential causal relationship between psoriasis and common mental disorders,and to provide genetic epidemiological evidence for the early intervention of mental comorbidities.[Methods]Based on publicly available large-scale GWAS data,a bidirectional Mendelian randomization(MR)approach was employed to assess the causal associations between psoriasis and major depressive disorder(MDD),bipolar disorder,schizophrenia,and anxiety disorders.The inverse variance weighted(IVW)method served as the primary analytical tool,supplemented by sensitivity analyses using MR-Egger and weighted median methods.Additionally,a subgroup analysis was conducted for psoriatic arthritis(PsA).[Results]Forward MR analysis revealed a significant positive causal association between the genetic predisposition to psoriasis and bipolar disorder as well as MDD,whereas no significant causal relationship was observed with schizophrenia or anxiety disorders.The reverse MR analysis found no causal effect of mental disorders on psoriasis.Subgroup analysis of PsA indicated that its genetic predisposition was significantly associated with the risk of bipolar disorder.The results of various sensitivity analyses and pleiotropy tests supported the robustness of the conclusions.[Conclusions]This study provides genetic evidence supporting a causal link between psoriasis and both MDD and bipolar disorder.In particular,patients with PsA are at a higher risk of developing bipolar disorder,highlighting the need to strengthen early screening and intervention for mental health in clinical management. 展开更多
关键词 PSORIASIS Mental disorders Major depressive disorder Bipolar disorder Mendelian randomization
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Lifestyle behaviors,serum metabolites and high myopia:Mendelian randomization and mediation analysis
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作者 Nian-En Liu Xiao-Tong Xu Xiao-Bing Yu 《International Journal of Ophthalmology(English edition)》 2026年第1期140-148,共9页
AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analy... AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analysis.METHODS:The causal effects of several behavioral factors,including screen time,education time,time spent outdoors,and physical activity,on the risk of HM using univariable Mendelian randomization(MR)and MVMR analyses were first assessed.Genome-wide association study summary statistics of serum metabolites were also used in mediation analysis to determine the extent to which serum metabolites mediate the effects of behavioral factors on HM.RESULTS:MR analyses indicated that both increased time spent outdoors and a higher frequency of moderate physical activity significantly reduced the risk of HM.Further MVMR analysis confirmed that moderate physical activity independently contributed to a lower risk of HM.Additionally,MR analyses identified 13 serum metabolites significantly associated with HM,of which 12 were lipids and one was an amino acid derivative.Mediation analysis revealed that six lipid metabolites mediated the protective effects of moderate physical activity on HM,with the highest mediation proportion observed for 1-(1-enyl-palmitoyl)-GPC(p-16:0;30.83%).CONCLUSION:This study suggests that in addition to outdoor time,moderate physical activity habits may have an independent protective effect against HM and pointed to lipid metabolites as priority targets for the prevention due to low physical activity.These results emphasize the importance of physical activity and metabolic health in HM and underscore the need for further study of these complex associations. 展开更多
关键词 high myopia physical activity serum metabolites multivariable Mendelian randomization mediation analysis
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Evaluation of spatial variability characteristics based on anisotropic modes of random fields
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作者 Kejing Chen Qinghui Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期494-508,共15页
This paper introduces a framework for modeling random fields,with a particular emphasis on analyzing anisotropic spatial variability.It establishes a clear connection between the correlation function and the Kriging v... This paper introduces a framework for modeling random fields,with a particular emphasis on analyzing anisotropic spatial variability.It establishes a clear connection between the correlation function and the Kriging variogram across various anisotropic modes,providing mathematical models to enhance our understanding of random fields.A new anisotropy index,called LSAI,is introduced to quantify anisotropy based on the autocorrelation length and the orientation of the principal axes within the variogram.An LSAI value closer to one indicates a lower degree of anisotropy.The present study examines how the degree of anisotropy varies with different autocorrelation lengths and angles between the principal axes,providing valuable insights into these relationships.To improve the accuracy of parameter probability distribution estimations,this study integrates limited field test data using a Bayesian inference approach.Additionally,the Markov chain Monte Carlo simulation method is employed to develop a conditional random field(CRF)for the deformation modulus.By incorporating data from field bearing plate tests,the posterior variance data for the deformation modulus are derived.This process facilitates the construction of a detailed and reliable CRF for the deformation modulus. 展开更多
关键词 Conditional random field(CRF) Anisotropic mode KRIGING Bayesian method VARIOGRAM
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Dissecting the Causal Association between Body Fat Mass and Obsessive-Compulsive Disorder:A Two-Sample Mendelian Randomization Study
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作者 Meiling Hu Zhennan Lin +2 位作者 Hongwei Liu Yunfeng Xi Youxin Wang 《Biomedical and Environmental Sciences》 2026年第1期36-45,共10页
Objective Previous studies link lower body mass index(BMI)with increased obsessive-compulsive disorder(OCD)risk,yet other body mass indicators may be more etioloically relevant.We dissected the causal association betw... Objective Previous studies link lower body mass index(BMI)with increased obsessive-compulsive disorder(OCD)risk,yet other body mass indicators may be more etioloically relevant.We dissected the causal association between body fat mass(FM)and OCD.Methods Summary statistics from genome-wide association studies of European ancestry were utilized to conduct two-sample Mendelian randomization analysis.Heterogeneity,horizontal pleiotropy,and sensitivity analyses were performed to assess the robustness.Results The inverse variance weighting method demonstrated that a genetically predicted decrease in FM was causally associated with an increased OCD risk[odds ratio(OR)=0.680,95%confidence interval(CI):0.528–0.875,P=0.003].Similar estimates were obtained using the weighted median approach(OR=0.633,95%CI:0.438–0.915,P=0.015).Each standard deviation increases in genetically predicted body fat percentage corresponded to a reduced OCD risk(OR=0.638,95%CI:0.455–0.896,P=0.009).The sensitivity analysis confirmed the robustness of these findings with no outlier instrument variables identified.Conclusion The negative causal association between FM and the risk of OCD suggests that the prevention or treatment of mental disorders should include not only the control of BMI but also fat distribution and body composition. 展开更多
关键词 Mendelian randomization Body fat mass Obsessive-compulsive disorder Causal inference
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Causal relationships between 41 inflammatory cytokines and myopia:a Mendelian randomization study
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作者 Xiao-Fei Wu Lei Yu +3 位作者 Ying Zhang Shuang Li Rui Li Lian-Yi Sun 《International Journal of Ophthalmology(English edition)》 2026年第3期575-581,共7页
AIM:To investigate the potential causal associations between 41 inflammatory cytokines and myopia using a two-sample Mendelian randomization(MR)approach.METHODS:Publicly available genome-wide association study(GWAS)da... AIM:To investigate the potential causal associations between 41 inflammatory cytokines and myopia using a two-sample Mendelian randomization(MR)approach.METHODS:Publicly available genome-wide association study(GWAS)datasets were utilized for this two-sample MR analysis.Inflammatory cytokine-related GWAS data were extracted from The University of Bristol’s Research Data Repository,and myopia-related GWAS data were obtained from the FinnGen project.Single nucleotide polymorphisms(SNPs)associated with inflammatory cytokines were systematically selected as instrumental variables(IVs)based on three rigorous criteria:relevance,independence,and exclusion of pleiotropy.Five MR methods were employed for causal inference:the inverse-variance weighted(IVW)method as the primary analysis,supplemented by MREgger regression,weighted median estimator,simple mode,and weighted mode approaches.Sensitivity analyses were performed to evaluate the robustness of the causal estimates.RESULTS:A total of 773 myopia-associated SNPs were identified.MR analysis revealed that higher levels of macrophage inflammatory protein 1-α(MIP-1α)were associated with a 17%reduced risk of myopia[odds ratio(OR)=0.83;95%confidence interval(CI):0.69-0.99;P<0.05].In contrast,elevated levels of eotaxin(OR=1.26;95%CI:1.07-1.47;P<0.01),stromal cell-derived factor-1α(SDF-1α;OR=1.68;95%CI:1.08-2.62;P<0.05),and interleukin-2 receptor subunit alpha(IL-2Rα;OR=1.25;95%CI:1.01-1.53;P<0.05)were significantly associated with an increased risk of myopia.Sensitivity analyses confirmed the reliability of these results.CONCLUSION:This study provides evidence supporting a causal relationship between specific inflammatory cytokines and myopia.MIP-1αmay act as a protective factor against myopia,while eotaxin,SDF-1α,and IL-2Rαare potential risk factors for myopia.These findings emphasize the critical role of inflammatory pathways in the pathogenesis of myopia,offering novel insights for the development of preventive and therapeutic strategies for myopia. 展开更多
关键词 MYOPIA inflammatory cytokines Mendelian randomization causal association single nucleotide polymorphism genome-wide association study
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Association between asthma and myopia:the NHANES database and Mendelian randomization analysis
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作者 Ya-Jing Zheng Ji-Fa Kuang +1 位作者 Fei-Lan Chen Wen-Bin Huang 《International Journal of Ophthalmology(English edition)》 2026年第1期132-139,共8页
AIM:To comprehensively assess the relationship between asthma and myopia based on the National Health and Nutrition Examination Survey(NHANES)database combined with Mendelian randomization(MR).METHODS:Initially,20497 ... AIM:To comprehensively assess the relationship between asthma and myopia based on the National Health and Nutrition Examination Survey(NHANES)database combined with Mendelian randomization(MR).METHODS:Initially,20497 subjects from the complete questionnaire cycle in the NHANES database from 2005 to 2008 were included.By exclusion criteria,8460 subjects were screened with 1676 myopia samples and 6784 control samples.Subsequently,baseline characteristics,association analyses,risk stratification analyses,and receive operating characteristic curve(ROC)were used to investigate the associations between covariates and myopia.Then,the causal relationship was explored in depth by MR analysis,and was estimated the reliability by sensitivity analyses and directionality tests.RESULTS:Baseline characteristics illustrated a significant difference between myopia and controls for both asthma and covariates(excluding gender;P<0.05).The results in all three models indicated that asthma was strongly associated with myopia and the effect on myopia was not significantly confounded by other covariates[model 3:odd ratio(OR)=1.31;95%CI=1.07-1.62;P=0.0133].The risk stratification analysis again verified that asthma remained strongly associated with myopia and was a risk factor for myopia(P<0.05,OR>1).ROC proved that the model was accurate in its prediction[area under curve(AUC)=0.7].Subsequently,the causal relationship between them was statistically significant(P<0.05)according to the inverse variance weighted(IVW)method in MR.Scatterplot showed that asthma and myopia had significant positive causality and were not affected by confounders.Forest plot displayed an increasing risk of myopia on asthma(OR>1).The funnel plot demonstrated compliance with Mendel’s second law.Sensitivity analysis and directional analysis further confirmed the confidence of the MR analysis results and a unidirectional causal relationship between them.CONCLUSION:A significant association and causality between asthma and myopia is found through the NHANES database and MR analysis,which is important implications for public health policy development and clinical practice. 展开更多
关键词 ASTHMA MYOPIA National Health and Nutrition Examination Survey Mendelian randomization
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Image recognition-based detection system for preventing accidental dislodgement of head-and-neck medical supplies in ICU patients:A feasibility randomized controlled trial
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作者 Zhongjie Shi Taotao Shi +5 位作者 Xin Gao Jian Li Hong Xu Xiaojun Li Zhanxiang Wang Sifang Chen 《International Journal of Nursing Sciences》 2026年第1期3-10,I0001,共9页
Objectives This study aimed to design and evaluate a detection system for the accidental dislodgement of head-and-neck medical supplies through hand position recognition and tracking in Intensive Care Unit(ICU)patient... Objectives This study aimed to design and evaluate a detection system for the accidental dislodgement of head-and-neck medical supplies through hand position recognition and tracking in Intensive Care Unit(ICU)patients.Methods We conducted a single-center,prospective,parallel-group feasibility randomized controlled trial.We recruited 80 participants using convenience sampling from the ICU of a hospital in Ningbo City,Zhejiang Province,between March 2025 and June 2025,and they were randomly assigned to either the control group(routine care)or the intervention group(routine care plus image recognition-based detection system).The system continuously tracked patients’hand positions via bedside cameras and generated real-time alarms when hands entered predefined risk zones,notifying on-duty nurses to enable early intervention.System stability was assessed by continuous system uptime;system performance and clinical feasibility were evaluated by the frequencies of risk actions and accidental dislodgement of medical supplies(ADMS).Results All 80 participants completed the intervention,with 40 patients in each group.The baseline characteristics and median observation time of the two groups were balanced(intervention group:48 h/patient vs.control group:49 h/patient).Compared with the control group,the intervention group showed fewer ADMS(2/40 vs.9/40)and detected more risk actions per 100 h(36 vs.25);all system-detected events had corroborating images with complete concordance on manual review,and all nurse-recorded hand-contact events were accurately captured.Conclusions The study demonstrated that the image recognition-based detection system can function stably in clinical settings,providing accurate and continuous surveillance while supporting the early detection of risk actions.By reducing the observation burden and offering real-time cognitive support,the system complements routine nursing care and serves as an additional safety measure in ICU practice.With further optimization and larger multicenter validation,this approach could have the potential to make a significant contribution to the development of smart ICUs and the broader digital transformation of nursing care. 展开更多
关键词 Accidental dislodgement of medical supplies Feasibility randomized trial Image recognition Intensive Care Unit Risk monitoring
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EXPONENTIAL STABILITY OF ATTRACTOR FOR RANDOM REACTION-DIFFUSION EQUATION DRIVEN BY NONLINEAR COLORED NOISE ON R^(N)
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作者 Huijuan ZHU Xiaojun LI Yanjiao LI 《Acta Mathematica Scientia》 2025年第4期1567-1596,共30页
In this paper, we consider the existence of pullback random exponential attractor for non-autonomous random reaction-diffusion equation driven by nonlinear colored noise defined onR^(N) . The key steps of the proof ar... In this paper, we consider the existence of pullback random exponential attractor for non-autonomous random reaction-diffusion equation driven by nonlinear colored noise defined onR^(N) . The key steps of the proof are the tails estimate and to demonstrate the Lipschitz continuity and random squeezing property of the solution for the equation defined on R^(N) . 展开更多
关键词 random reaction-diffusion equation continuous cocycle pullback random attractor fractal dimension random exponential attractor
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Evaluating Domain Randomization Techniques in DRL Agents:A Comparative Study of Normal,Randomized,and Non-Randomized Resets
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作者 Abubakar Elsafi 《Computer Modeling in Engineering & Sciences》 2025年第8期1749-1766,共18页
Domain randomization is a widely adopted technique in deep reinforcement learning(DRL)to improve agent generalization by exposing policies to diverse environmental conditions.This paper investigates the impact of diff... Domain randomization is a widely adopted technique in deep reinforcement learning(DRL)to improve agent generalization by exposing policies to diverse environmental conditions.This paper investigates the impact of different reset strategies,normal,non-randomized,and randomized,on agent performance using the Deep Deterministic Policy Gradient(DDPG)and Twin Delayed DDPG(TD3)algorithms within the CarRacing-v2 environment.Two experimental setups were conducted:an extended training regime with DDPG for 1000 steps per episode across 1000 episodes,and a fast execution setup comparing DDPG and TD3 for 30 episodes with 50 steps per episode under constrained computational resources.A step-based reward scaling mechanism was applied under the randomized reset condition to promote broader state exploration.Experimental results showthat randomized resets significantly enhance learning efficiency and generalization,with DDPG demonstrating superior performance across all reset strategies.In particular,DDPG combined with randomized resets achieves the highest smoothed rewards(reaching approximately 15),best stability,and fastest convergence.These differences are statistically significant,as confirmed by t-tests:DDPG outperforms TD3 under randomized(t=−101.91,p<0.0001),normal(t=−21.59,p<0.0001),and non-randomized(t=−62.46,p<0.0001)reset conditions.The findings underscore the critical role of reset strategy and reward shaping in enhancing the robustness and adaptability of DRL agents in continuous control tasks,particularly in environments where computational efficiency and training stability are crucial. 展开更多
关键词 DDPG agent TD3 agent deep reinforcement learning domain randomization generalization non-randomized reset normal reset randomized reset
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THE CONSTRUCTION OF MULTITYPE CANONICAL MARKOV BRANCHING CHAINS IN RANDOM ENVIRONMENTS 被引量:2
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期431-442,共12页
The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introd... The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introduces the concepts of the multitype canonical Markov branching chain in random environment (CMBCRE) and multitype Markov branching chain in random environment (MBCRE) and proved that CMBCRE must be MBCRE, and any MBCRE must be equivalent to another CMBCRE in distribution. The main results of this article are the construction of CMBCRE and some of its probability properties. 展开更多
关键词 random Markov matrix Markov chain in random environment Markov branching chain in random environment canonical Markov branching chain in random environment generator random variables
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THE ANALYTICAL PROPERTIES FOR HOMOGENEOUS RANDOM TRANSITION FUNCTIONS 被引量:1
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作者 胡迪鹤 邱育峰 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期180-192,共13页
The concepts of Markov process in random environment and homogeneous random transition functions are introduced. The necessary and sufficient conditions for homogeneous random transition function are given. The main r... The concepts of Markov process in random environment and homogeneous random transition functions are introduced. The necessary and sufficient conditions for homogeneous random transition function are given. The main results in this article are the analytical properties, such as continuity, differentiability, random Kolmogorov backward equation and random Kolmogorov forward equation of homogeneous random transition functions. 展开更多
关键词 Markov process in random environment random transition function homogeneous random transition function random Kohnogorov backward equation random Kohnogorov forward equation
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THE ERGODICITY FOR BI-IMMIGRATION BIRTH AND DEATH PROCESSES IN RANDOM ENVIRONMENT 被引量:1
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作者 Hu Dihe Zhang Shuli 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期43-53,共11页
The concepts of bi-immigration birth and death density matrix in random environment and bi-immigration birth and death process in random environment are introduced.For any bi-immigration birth and death matrix in rand... The concepts of bi-immigration birth and death density matrix in random environment and bi-immigration birth and death process in random environment are introduced.For any bi-immigration birth and death matrix in random environment Q(θ)with birth rateλ〈death rateμ,the following results are proved,(1)there is an unique q-process in random environment,P^-(θ*(0);t)=(p^-(θ^*(0);t,i,j),i,j≥0),which is ergodic,that is,lim t→∞(θ^*(0);t,i,j)=π^-(θ^*(0);j)≥0 does not depend on i≥0 and∑j≥0π(θ*(0);j)=1,(2)there is a bi-immigration birth and death process in random enjvironment(X^*={X^*,t≥0},ε^*={εt,t∈(-∞,∞)})with random transition matrix P^-(θ^*(0);t)such that X^*is a strictly stationary process. 展开更多
关键词 Density matrix in random environment random transition matrix Markov process in random environment bi-immigration birth and death density matrix in random environment bi-immigration birth and death process in random environment
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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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ISOPERIMETRIC INEQUALITIES FOR INTEGRAL GEOMETRIC INVARIANTS OF RANDOM LINES
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作者 Gaoyong ZHANG 《Acta Mathematica Scientia》 2025年第1期189-199,共11页
Isoperimetric type inequalities for integral geometric invariants of random lines in the Euclidean space are shown.Entropy inequalities of probability densities on the affine Grassmann manifold of lines are given.
关键词 isoperimetric inequality convex body random points random lines chord integral Riesz potential ENTROPY
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Current state of nutritional psychiatry:A scoping review of randomized controlled trials
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作者 Takahiko Nagamine 《World Journal of Methodology》 2025年第4期364-373,共10页
BACKGROUND Nutritional psychiatry is a rapidly expanding field of research,with mounting evidence suggesting that nutritional factors may play a role in the development of psychiatric disorders.AIM To examine the leve... BACKGROUND Nutritional psychiatry is a rapidly expanding field of research,with mounting evidence suggesting that nutritional factors may play a role in the development of psychiatric disorders.AIM To examine the level of evidence for nutritional psychiatry.METHODS A scoping review was conducted to assess the current state of nutritional psychiatry,including a search for randomized controlled trials(RCTs).RESULTS The review identified a total of seven papers,with many concentrating on the relationship between depression and the gut microbiome.A salient issue that emerged from this review was the paucity of sample size in many studies.The inherent complexity of nutritional studies,characterized by a multitude of potential factors and exposures that often act as confounders,poses significant challenges to the development of effective RCT designs.The analysis revealed that probiotics,though demonstrating efficacy,exhibited a modest effect size.CONCLUSION Conducting RCTs with effective markers is imperative from these studies.The implementation of Mendelian randomization and the investigation of mechanisms in basic research are essential complementary approaches. 展开更多
关键词 Nutritional psychiatry randomized controlled trial Mendelian randomization Fundamental research PROBIOTICS Gut microbiota
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A CGAN Framework for Predicting Crack Patterns and Stress-Strain Behavior in Concrete Random Media
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作者 Xing Lin Junning Wu Shixue Liang 《Computer Modeling in Engineering & Sciences》 2025年第10期215-239,共25页
Random media like concrete and ceramics exhibit stochastic crack propagation due to their heterogeneous microstructures.This study establishes a Conditional Generative Adversarial Network(CGAN)combined with randomfiel... Random media like concrete and ceramics exhibit stochastic crack propagation due to their heterogeneous microstructures.This study establishes a Conditional Generative Adversarial Network(CGAN)combined with randomfieldmodeling for the efficient prediction of stochastic crack patterns and stress-strain responses.Atotal dataset of 500 samples,including crack propagation images and corresponding stress-strain curves,is generated via random Finite Element Method(FEM)simulations.This dataset is then partitioned into 400 training and 100 testing samples.Themodel demonstrates robust performance with Intersection overUnion(IoU)scores of 0.8438 and 0.8155 on training and testing datasets,and R2 values of 0.9584 and 0.9462 in stress-strain curve predictions.By using these results,the CGAN is subsequently implemented as a surrogate model for large-scale Monte Carlo(MC)Simulations to capture the key statistical characteristics such as crack density and spatial distribution.Compared to conventional FEM-based methods,this approach reduces the computational cost to about 1/250 while maintaining high prediction accuracy.The methodology establishes a viable pathway for probabilistic fracture analysis in quasi-brittle materials,balancing computational efficiency with physical fidelity in capturing material stochasticity. 展开更多
关键词 random media CONCRETE stochastic crack patterns random field deep learning method surrogate model
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A method for predicting random vibration response of train-track-bridge system based on GA-BP neural network
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作者 Jianfeng Mao Yun Zhang +2 位作者 Li Zheng Mansoor Khan Zhiwu Yu 《High-Speed Railway》 2025年第4期305-317,共13页
To enhance the efficiency of stochastic vibration analysis for the Train-Track-Bridge(TTB)coupled system,this paper proposes a prediction method based on a Genetic Algorithm-optimized Backpropagation(GA-BP)neural netw... To enhance the efficiency of stochastic vibration analysis for the Train-Track-Bridge(TTB)coupled system,this paper proposes a prediction method based on a Genetic Algorithm-optimized Backpropagation(GA-BP)neural network.First,initial track irregularity samples and random parameter sets of the Vehicle-Bridge System(VBS)are generated using the stochastic harmonic function method.Then,the stochastic dynamic responses corresponding to the sample sets are calculated using a developed stochastic vibration analysis model of the TTB system.The track irregularity data and vehicle-bridge random parameters are used as input variables,while the corresponding stochastic responses serve as output variables for training the BP neural network to construct the prediction model.Subsequently,the Genetic Algorithm(GA)is applied to optimize the BP neural network by considering the randomness in excitation and parameters of the TTB system,improving model accuracy.After optimization,the trained GA-BP model enables rapid and accurate prediction of vehicle-bridge responses.To validate the proposed method,predictions of vehicle-bridge responses under varying train speeds are compared with numerical simulation results.The findings demonstrate that the proposed method offers notable advantages in predicting the stochastic vibration response of high-speed railway TTB coupled systems. 展开更多
关键词 Train-track-bridge system Genetic algorithm BP neural network random response prediction random parameters
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