BACKGROUND Adolescent major depressive disorder(MDD)is a significant mental health concern that often leads to recurrent depression in adulthood.Resting-state functional magnetic resonance imaging(rs-fMRI)offers uniqu...BACKGROUND Adolescent major depressive disorder(MDD)is a significant mental health concern that often leads to recurrent depression in adulthood.Resting-state functional magnetic resonance imaging(rs-fMRI)offers unique insights into the neural mechanisms underlying this condition.However,despite previous research,the specific vulnerable brain regions affected in adolescent MDD patients have not been fully elucidated.AIM To identify consistent vulnerable brain regions in adolescent MDD patients using rs-fMRI and activation likelihood estimation(ALE)meta-analysis.METHODS We performed a comprehensive literature search through July 12,2023,for studies investigating brain functional changes in adolescent MDD patients.We utilized regional homogeneity(ReHo),amplitude of low-frequency fluctuations(ALFF)and fractional ALFF(fALFF)analyses.We compared the regions of aberrant spontaneous neural activity in adolescents with MDD vs healthy controls(HCs)using ALE.RESULTS Ten studies(369 adolescent MDD patients and 313 HCs)were included.Combining the ReHo and ALFF/fALFF data,the results revealed that the activity in the right cuneus and left precuneus was lower in the adolescent MDD patients than in the HCs(voxel size:648 mm3,P<0.05),and no brain region exhibited increased activity.Based on the ALFF data,we found decreased activity in the right cuneus and left precuneus in adolescent MDD patients(voxel size:736 mm3,P<0.05),with no regions exhibiting increased activity.CONCLUSION Through ALE meta-analysis,we consistently identified the right cuneus and left precuneus as vulnerable brain regions in adolescent MDD patients,increasing our understanding of the neuropathology of affected adolescents.展开更多
This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA（1, 1） model, where maximizing likelihood function is equivalent ...This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA（1, 1） model, where maximizing likelihood function is equivalent to maximizing its logarithm, so the objective function ＇obj.fun＇ is maximizing log-likelihood function. Monte Carlo method adapted for implementing and designing the experiments of this simulation. This study including a comparison among three versions of PSO algorithm “Constriction coefficient CCPSO, Inertia weight IWPSO, and Fully Informed FIPSO”, the experiments designed by setting different values of model parameters al, bs sample size n, moreover the parameters of PSO algorithms. MSE used as test statistic to measure the efficiency PSO to estimate model. The results show the ability of PSO to estimate ARMA＇ s parameters, and the minimum values of MSE getting for COPSO.展开更多
BACKGROUND Attention deficit hyperactivity disorder(ADHD)is a prevalent neurodevelopmental disorder in adolescents characterized by inattention,hyperactivity,and impulsivity,which impact cognitive,behavioral,and emoti...BACKGROUND Attention deficit hyperactivity disorder(ADHD)is a prevalent neurodevelopmental disorder in adolescents characterized by inattention,hyperactivity,and impulsivity,which impact cognitive,behavioral,and emotional functioning.Resting-state functional magnetic resonance imaging(rs-fMRI)provides critical insights into the functional architecture of the brain in ADHD.Despite extensive research,specific brain regions consistently affected in ADHD patients during these formative years have not been comprehensively delineated.AIM To identify consistent vulnerable brain regions in adolescent ADHD patients using rs-fMRI and activation likelihood estimation(ALE)meta-analysis.METHODS We conducted a comprehensive literature search up to August 31,2024,to identify studies investigating functional brain alterations in adolescents with ADHD.We utilized regional homogeneity(ReHo),amplitude of low-frequency fluctuations(ALFF),dynamic ALFF(dALFF)and fractional ALFF(fALFF)analyses.We compared the regions of aberrant spontaneous neural activity in adolescents with ADHD with those in healthy controls(HCs)using ALE.RESULTS Fifteen studies(468 adolescent ADHD patients and 466 HCs)were included.Combining the ReHo and ALFF/fALFF/dALFF data,the results revealed increased activity in the right lingual gyrus[LING,Brodmann Area(BA)18],left LING(BA 18),and right cuneus(CUN,BA 23)in adolescent ADHD patients compared with HCs(voxel size:592-32 mm³,P<0.05).Decreased activity was observed in the left medial frontal gyrus(MFG,BA 9)and left precuneus(PCUN,BA 31)in adolescent ADHD patients compared with HCs(voxel size:960-456 mm³,P<0.05).Jackknife sensitivity analyses demonstrated robust reproducibility in 11 of the 13 tests for the right LING,left LING,and right CUN and in 11 of the 14 tests for the left MFG and left PCUN.CONCLUSION We identified specific brain regions with both increased and decreased activity in adolescent ADHD patients,enhancing our understanding of the neural alterations that occur during this pivotal stage of development.展开更多
目的探讨应用静息态功能磁共振研究耳鸣患者较为一致的活动异常脑区,从而揭示耳鸣患者脑损伤及功能重塑的神经机制。方法检索1999年1月1日至2023年10月12日采用局部一致性(regional honogeneity,ReHo)及低频振幅(amplitude of low-frequ...目的探讨应用静息态功能磁共振研究耳鸣患者较为一致的活动异常脑区,从而揭示耳鸣患者脑损伤及功能重塑的神经机制。方法检索1999年1月1日至2023年10月12日采用局部一致性(regional honogeneity,ReHo)及低频振幅(amplitude of low-frequency fluctuation,ALFF)、分数低频振幅指标评估耳鸣患者脑功能改变的文献,按照严格的纳排标准,采用激活似然估计法对既往研究中耳鸣患者相对于健康对照组自发脑神经活动异常的脑区进行整合分析。结果共纳入22篇29个研究(耳鸣患者746例,健康对照组653例),联合ALFF、分数低频振幅与ReHo数据Meta分析结果显示,耳鸣患者相对于健康对照组,右颞中回活动增加,并未发现活动减低的脑区;单独ReHo数据分析结果显示,左侧枕中回、左侧后扣带回活动增加;右背外侧额上回、左侧小脑前叶活动减少;单独ALFF数据分析结果显示,耳鸣患者相对于健康对照组未出现任何活动增高或减低的脑区(体素大小≥200 mm^(3),FDR P<0.05)。结论运用激活似然估计法-Meta分析方法证实耳鸣患者多个脑区存在自发活动异常,有助于揭示耳鸣脑功能损伤及重塑的神经病理学基础。展开更多
针对输油气管道的故障种类多、现场数据无法长期有效保存等问题,提出了一种基于边缘计算和改进随机向量函数链接(random vector functional-link,RVFL)网络的输油气管道故障分类方法。该方法扩展了监控和数据采集(supervisory control a...针对输油气管道的故障种类多、现场数据无法长期有效保存等问题,提出了一种基于边缘计算和改进随机向量函数链接(random vector functional-link,RVFL)网络的输油气管道故障分类方法。该方法扩展了监控和数据采集(supervisory control and data acquisition,SCADA)系统的功能,使其可以存储和访问大量的数据。首先,当输油气管道出现故障时,利用基于模糊似然函数的模糊聚类算法对故障发生前一段时间内的管道压力值进行聚类;然后,提取管道压力值密度特征,将其作为RVFL网络的增强节点,利用改进RVFL网络对故障进行分类。将改进RVFL网络部署在边缘计算模块中,对6种故障进行分类,其准确率可达到96.7%。展开更多
目的通过荟萃分析探讨慢性颈肩痛(chronic neck and shoulder pain,CNSP)患者的脑自发活动改变特点,从而揭示CNSP可能的中枢神经机制,为后期定位CNSP患者疼痛治疗中枢靶点及客观评估治疗效果奠定基础。方法在线检索14年4月至24年4月发表...目的通过荟萃分析探讨慢性颈肩痛(chronic neck and shoulder pain,CNSP)患者的脑自发活动改变特点,从而揭示CNSP可能的中枢神经机制,为后期定位CNSP患者疼痛治疗中枢靶点及客观评估治疗效果奠定基础。方法在线检索14年4月至24年4月发表在PubMed、Web of Science、EMBase、The Cochrane Library、CNKI、CBM、维普网、万方数据库中采用低频振幅(amplitude of low-frequency fluctuation,ALFF)/比率低频振幅(fractional amplitude of low-frequency fluctuation,fALFF)及局部一致性(regional homogeneity,ReHo)分析方法研究CNSP患者脑自发活动改变的文献。采用激活似然估计法(activation likelihood estimation,ALE)对纳入研究中CNSP患者相对于健康对照组(healthy controls,HCs)脑自发活动出现异常改变的脑区进行元分析。结果共纳入11篇文献,包括6项ALFF/fALFF、5项ReHo研究(CNSP患者445例,健康受试者384例)的数据。分析结果显示:CNSP患者相对于健康对照组(HCs)左侧岛叶皮层和纹状体的脑自发活动增高,而左侧中央前回、左侧中央后回和左侧顶上小叶的脑自发活动减低。结论慢性颈肩痛患者在与感觉、运动、情感以及疼痛的上行传导和下行调控方面相关的多个大脑区域存在脑自发活动的异常改变,这些变化可能是长期的慢性颈肩痛所导致的,本研究为后期通过CNSP患者的脑自发活动改变定位CNSP患者疼痛治疗中枢靶点以及客观评估CNSP治疗效果提供了重要参考。展开更多
In virtue of the notion of likelihood ratio and moment generating function, the limit properties of the sequences of absolutely continuous random variables are studied, and a class of strong limit theorems represented...In virtue of the notion of likelihood ratio and moment generating function, the limit properties of the sequences of absolutely continuous random variables are studied, and a class of strong limit theorems represented by inequalities with random bounds are obtained.展开更多
OBJECTIVE: The objective of this study is to summarize and analyze the brain signal patterns of empathy for pain caused by facial expressions of pain utilizing activation likelihood estimation, a meta-analysis method....OBJECTIVE: The objective of this study is to summarize and analyze the brain signal patterns of empathy for pain caused by facial expressions of pain utilizing activation likelihood estimation, a meta-analysis method. DATA SOURCES: Studies concerning the brain mechanism were searched from the Science Citation Index, Science Direct, PubMed, DeepDyve, Cochrane Library, SinoMed, Wanfang, VIP, China National Knowledge Infrastructure, and other databases, such as SpringerLink, AMA, Science Online, Wiley Online, were collected. A time limitation of up to 13 December 2016 was applied to this study. DATA SELECTION: Studies presenting with all of the following criteria were considered for study inclusion: Use of functional magnetic resonance imaging, neutral and pained facial expression stimuli, involvement of adult healthy human participants over 18 years of age, whose empathy ability showed no difference from the healthy adult, a painless basic state, results presented in Talairach or Montreal Neurological Institute coordinates, multiple studies by the same team as long as they used different raw data. OUTCOME MEASURES: Activation likelihood estimation was used to calculate the combined main activated brain regions under the stimulation of pained facial expression. RESULTS: Eight studies were included, containing 178 subjects. Meta-analysis results suggested that the anterior cingulate cortex(BA32), anterior central gyrus(BA44), fusiform gyrus, and insula(BA13) were activated positively as major brain areas under the stimulation of pained facial expression. CONCLUSION: Our study shows that pained facial expression alone, without viewing of painful stimuli, activated brain regions related to pain empathy, further contributing to revealing the brain's mechanisms of pain empathy.展开更多
This in virtue of the notion of likelihood ratio and the tool of moment generating function, the limit properties of the sequences of random discrete random variables are studied, and a class of strong deviation theor...This in virtue of the notion of likelihood ratio and the tool of moment generating function, the limit properties of the sequences of random discrete random variables are studied, and a class of strong deviation theorems which represented by inequalities between random variables and their expectation are obtained. As a result, we obtain some strong deviation theorems for Poisson distribution and binomial distribution.展开更多
In this article, we propose a generalized empirical likelihood inference for the parametric component in semiparametric generalized partially linear models with longitudinal data. Based on the extended score vector, a...In this article, we propose a generalized empirical likelihood inference for the parametric component in semiparametric generalized partially linear models with longitudinal data. Based on the extended score vector, a generalized empirical likelihood ratios function is defined, which integrates the within-cluster?correlation meanwhile avoids direct estimating the nuisance parameters in the correlation matrix. We show that the proposed statistics are asymptotically?Chi-squared under some suitable conditions, and hence it can be used to construct the confidence region of parameters. In addition, the maximum empirical likelihood estimates of parameters and the corresponding asymptotic normality are obtained. Simulation studies demonstrate the performance of the proposed method.展开更多
This paper mainly addresses maximum likelihood estimation for a response-selective stratified sampling scheme, the basic stratified sampling (BSS), in which the maximum subsample size in each stratum is fixed. We deri...This paper mainly addresses maximum likelihood estimation for a response-selective stratified sampling scheme, the basic stratified sampling (BSS), in which the maximum subsample size in each stratum is fixed. We derived the complete-data likelihood for BSS, and extended it as a full-data likelihood by incorporating incomplete data. We also similarly extended the empirical proportion likelihood approach for consistent and efficient estimation. We conducted a simulation study to compare these two new approaches with the existing estimation methods in BSS. Our result indicates that they perform as well as the standard full information likelihood approach. Methods were illustrated using a growth model for fish size at age, including between-individual variability. One of our major conclusions is that the fully observed BSS data, the partially observed data used for stratification, and the sampling strategy are all important in constructing a consistent and efficient estimator.展开更多
We characterize the hemodynamic response changes near-infrared spectroscopy （NIRS） during the presentation of in the main olfactory bulb （MOB） of anesthetized rats with three different odorants： （i） plain air a...We characterize the hemodynamic response changes near-infrared spectroscopy （NIRS） during the presentation of in the main olfactory bulb （MOB） of anesthetized rats with three different odorants： （i） plain air as a reference （Blank）, （ii） 2-heptanone （HEP）, and （iii） isopropylbenzene （Ib）. Odorants generate different changes in the concentrations of oxy- hemoglobin. Our results suggest that NIRS technology might be useful in discriminating various odorants in a non-invasive manner using animals with a superb olfactory system.展开更多
The likelihood function plays a central role in statistical analysis in relation to information, from both frequentist and Bayesian perspectives. In large samples several new properties of the likelihood in relation t...The likelihood function plays a central role in statistical analysis in relation to information, from both frequentist and Bayesian perspectives. In large samples several new properties of the likelihood in relation to information are developed here. The Arrow-Pratt absolute risk aversion measure is shown to be related to the Cramer-Rao Information bound. The derivative of the log-likelihood function is seen to provide a measure of information related stability for the Bayesian posterior density. As well, information similar prior densities can be defined reflecting the central role of likelihood in the Bayes learning paradigm.展开更多
In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the...In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the assumption that the distribution of observations is unimodal and symmetry, this method can give the estimates of the parametric. Finally, two simulated adjustment problem are constructed to explain this method. The new method presented in this paper shows an effective way of solving the problem; the estimated values are nearer to their theoretical ones than those by least squares adjustment approach.展开更多
The calibration of transfer functions is essential for accurate pavement performance predictions in the PavementME design. Several studies have used the least square approach to calibrate these transfer functions. Lea...The calibration of transfer functions is essential for accurate pavement performance predictions in the PavementME design. Several studies have used the least square approach to calibrate these transfer functions. Least square is a widely used simplistic approach based on certain assumptions. Literature shows that these least square approach assumptions may not apply to the non-normal distributions. This study introduces a new methodology for calibrating the transverse cracking and international roughness index(IRI) models in rigid pavements using maximum likelihood estimation(MLE). Synthetic data for transverse cracking, with and without variability, are generated to illustrate the applicability of MLE using different known probability distributions(exponential,gamma, log-normal, and negative binomial). The approach uses measured data from the Michigan Department of Transportation's(MDOT) pavement management system(PMS) database for 70 jointed plain concrete pavement(JPCP) sections to calibrate and validate transfer functions. The MLE approach is combined with resampling techniques to improve the robustness of calibration coefficients. The results show that the MLE transverse cracking model using the gamma distribution consistently outperforms the least square for synthetic and observed data. For observed data, MLE estimates of parameters produced lower SSE and bias than least squares(e.g., for the transverse cracking model, the SSE values are 3.98 vs. 4.02, and the bias values are 0.00 and-0.41). Although negative binomial distribution is the most suitable fit for the IRI model for MLE, the least square results are slightly better than MLE. The bias values are-0.312 and 0.000 for the MLE and least square methods. Overall, the findings indicate that MLE is a robust method for calibration, especially for non-normally distributed data such as transverse cracking.展开更多
目的通过激活似然估计(ALE)的荟萃分析方法探讨感觉神经性耳聋(SNHL)病人的脑自发活动改变特点,进一步了解SNHL可能存在的脑功能损伤及重塑的神经机制。方法检索2023年8月21日之前Web of Science、PubMed、CNKI、万方医学网、中华医学...目的通过激活似然估计(ALE)的荟萃分析方法探讨感觉神经性耳聋(SNHL)病人的脑自发活动改变特点,进一步了解SNHL可能存在的脑功能损伤及重塑的神经机制。方法检索2023年8月21日之前Web of Science、PubMed、CNKI、万方医学网、中华医学期刊全文数据库中采用局部一致性(ReHo)及低频振幅/分数低频振幅(ALFF/fALFF)分析SNHL病人脑功能改变的文献,按照纳排标准对文献筛选后,采用激活似然估计法(ALE)纳入研究中SNHL病人自发脑神经活动异常的脑区进行Meta分析。结果共纳入22篇29项研究(SNHL 736例,对照487例),其中ReHo研究11项,ALFF/fALFF研究18项。联合ReHo/ALFF/fALFF分析方法且不区分耳聋侧别结果显示SNHL病人左侧丘脑背内侧核自发脑活动增加,左侧颞上回、左侧额下回岛盖部及左侧背外侧前额叶自发脑活动减低。分别依次对左/右耳SNHL病人、ReHo和ALFF/fALFF方法进行ALE分析,结果均未见任何异常活动脑区。结论运用ALE荟萃分析方法证实SNHL病人多个脑区存在自发活动异常,有助于进一步了解SNHL脑功能损伤及重塑的规律及特征,为其后续诊疗评估提供重要依据。展开更多
基金Supported by The 2024 Guizhou Provincial Health Commission Science and Technology Fund Project,No.gzwkj2024-47502022 Provincial Clinical Key Specialty Construction Project。
文摘BACKGROUND Adolescent major depressive disorder(MDD)is a significant mental health concern that often leads to recurrent depression in adulthood.Resting-state functional magnetic resonance imaging(rs-fMRI)offers unique insights into the neural mechanisms underlying this condition.However,despite previous research,the specific vulnerable brain regions affected in adolescent MDD patients have not been fully elucidated.AIM To identify consistent vulnerable brain regions in adolescent MDD patients using rs-fMRI and activation likelihood estimation(ALE)meta-analysis.METHODS We performed a comprehensive literature search through July 12,2023,for studies investigating brain functional changes in adolescent MDD patients.We utilized regional homogeneity(ReHo),amplitude of low-frequency fluctuations(ALFF)and fractional ALFF(fALFF)analyses.We compared the regions of aberrant spontaneous neural activity in adolescents with MDD vs healthy controls(HCs)using ALE.RESULTS Ten studies(369 adolescent MDD patients and 313 HCs)were included.Combining the ReHo and ALFF/fALFF data,the results revealed that the activity in the right cuneus and left precuneus was lower in the adolescent MDD patients than in the HCs(voxel size:648 mm3,P<0.05),and no brain region exhibited increased activity.Based on the ALFF data,we found decreased activity in the right cuneus and left precuneus in adolescent MDD patients(voxel size:736 mm3,P<0.05),with no regions exhibiting increased activity.CONCLUSION Through ALE meta-analysis,we consistently identified the right cuneus and left precuneus as vulnerable brain regions in adolescent MDD patients,increasing our understanding of the neuropathology of affected adolescents.
文摘This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA（1, 1） model, where maximizing likelihood function is equivalent to maximizing its logarithm, so the objective function ＇obj.fun＇ is maximizing log-likelihood function. Monte Carlo method adapted for implementing and designing the experiments of this simulation. This study including a comparison among three versions of PSO algorithm “Constriction coefficient CCPSO, Inertia weight IWPSO, and Fully Informed FIPSO”, the experiments designed by setting different values of model parameters al, bs sample size n, moreover the parameters of PSO algorithms. MSE used as test statistic to measure the efficiency PSO to estimate model. The results show the ability of PSO to estimate ARMA＇ s parameters, and the minimum values of MSE getting for COPSO.
基金Supported by National Natural Science Foundation of China,No.82460282Guizhou Province Science and Technology Plan Project,No.ZK-2023-195+1 种基金Guizhou High-Level Innovative Talent Project,No.gzwjrs2022-013Health Commission of Guizhou Province Project,No.gzwkj2024-475 and No.gzwkj2021-150.
文摘BACKGROUND Attention deficit hyperactivity disorder(ADHD)is a prevalent neurodevelopmental disorder in adolescents characterized by inattention,hyperactivity,and impulsivity,which impact cognitive,behavioral,and emotional functioning.Resting-state functional magnetic resonance imaging(rs-fMRI)provides critical insights into the functional architecture of the brain in ADHD.Despite extensive research,specific brain regions consistently affected in ADHD patients during these formative years have not been comprehensively delineated.AIM To identify consistent vulnerable brain regions in adolescent ADHD patients using rs-fMRI and activation likelihood estimation(ALE)meta-analysis.METHODS We conducted a comprehensive literature search up to August 31,2024,to identify studies investigating functional brain alterations in adolescents with ADHD.We utilized regional homogeneity(ReHo),amplitude of low-frequency fluctuations(ALFF),dynamic ALFF(dALFF)and fractional ALFF(fALFF)analyses.We compared the regions of aberrant spontaneous neural activity in adolescents with ADHD with those in healthy controls(HCs)using ALE.RESULTS Fifteen studies(468 adolescent ADHD patients and 466 HCs)were included.Combining the ReHo and ALFF/fALFF/dALFF data,the results revealed increased activity in the right lingual gyrus[LING,Brodmann Area(BA)18],left LING(BA 18),and right cuneus(CUN,BA 23)in adolescent ADHD patients compared with HCs(voxel size:592-32 mm³,P<0.05).Decreased activity was observed in the left medial frontal gyrus(MFG,BA 9)and left precuneus(PCUN,BA 31)in adolescent ADHD patients compared with HCs(voxel size:960-456 mm³,P<0.05).Jackknife sensitivity analyses demonstrated robust reproducibility in 11 of the 13 tests for the right LING,left LING,and right CUN and in 11 of the 14 tests for the left MFG and left PCUN.CONCLUSION We identified specific brain regions with both increased and decreased activity in adolescent ADHD patients,enhancing our understanding of the neural alterations that occur during this pivotal stage of development.
文摘研究伴自杀意念(suicidal ideation,SI)的抑郁症患者、不伴自杀意念(no suicidal ideation,NSI)的抑郁症患者、健康对照(healthy controls,HC)的静息态功能性核磁共振(resting-state functional magnetic resonance imaging,rs-fMRI)低频振幅(amplitude of low frequency fluctuations,ALFF)的活动差异,通过对患者rs-fMRI的脑功能进行Meta分析。在Pubmed、Embase、Web of Science、Cochrane Library、中国知网、万方数据库中搜索关于伴SI的抑郁患者rs-fMRI的相关文献。依据系统评价的方法,对纳入文献进行筛选、质量评价、提取特征、激活似然估计法(activation likelihood estimation,ALE)Meta分析,汇总了既往文献的SI抑郁症患者、NSI抑郁症患者与HC之间的ALFF的收敛脑区。共纳入6篇文献,提取SI组患者175例,NSI组患者137例,HC组125名,其中SI组和NSI组之间的差异脑区共有18个。将差异脑区纳入ALE Meta分析,结果显示:SI组相较于NSI组ALFF增高的脑区有左侧枕叶舌回(ALE=1.859×10^(-2),P<0.01,Z=5.688)、右侧枕中回(ALE=1.823×10^(-2),P<0.01,Z=5.562)。左侧枕叶舌回及右侧枕中回异常激活与抑郁症患者的自杀意念可能相关。
文摘针对输油气管道的故障种类多、现场数据无法长期有效保存等问题,提出了一种基于边缘计算和改进随机向量函数链接(random vector functional-link,RVFL)网络的输油气管道故障分类方法。该方法扩展了监控和数据采集(supervisory control and data acquisition,SCADA)系统的功能,使其可以存储和访问大量的数据。首先,当输油气管道出现故障时,利用基于模糊似然函数的模糊聚类算法对故障发生前一段时间内的管道压力值进行聚类;然后,提取管道压力值密度特征,将其作为RVFL网络的增强节点,利用改进RVFL网络对故障进行分类。将改进RVFL网络部署在边缘计算模块中,对6种故障进行分类,其准确率可达到96.7%。
文摘目的通过荟萃分析探讨慢性颈肩痛(chronic neck and shoulder pain,CNSP)患者的脑自发活动改变特点,从而揭示CNSP可能的中枢神经机制,为后期定位CNSP患者疼痛治疗中枢靶点及客观评估治疗效果奠定基础。方法在线检索14年4月至24年4月发表在PubMed、Web of Science、EMBase、The Cochrane Library、CNKI、CBM、维普网、万方数据库中采用低频振幅(amplitude of low-frequency fluctuation,ALFF)/比率低频振幅(fractional amplitude of low-frequency fluctuation,fALFF)及局部一致性(regional homogeneity,ReHo)分析方法研究CNSP患者脑自发活动改变的文献。采用激活似然估计法(activation likelihood estimation,ALE)对纳入研究中CNSP患者相对于健康对照组(healthy controls,HCs)脑自发活动出现异常改变的脑区进行元分析。结果共纳入11篇文献,包括6项ALFF/fALFF、5项ReHo研究(CNSP患者445例,健康受试者384例)的数据。分析结果显示:CNSP患者相对于健康对照组(HCs)左侧岛叶皮层和纹状体的脑自发活动增高,而左侧中央前回、左侧中央后回和左侧顶上小叶的脑自发活动减低。结论慢性颈肩痛患者在与感觉、运动、情感以及疼痛的上行传导和下行调控方面相关的多个大脑区域存在脑自发活动的异常改变,这些变化可能是长期的慢性颈肩痛所导致的,本研究为后期通过CNSP患者的脑自发活动改变定位CNSP患者疼痛治疗中枢靶点以及客观评估CNSP治疗效果提供了重要参考。
基金Supported by the National Nature Science Foundation of China (Grant No. 11101014)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20101103120016)+4 种基金the Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality (Grant No. PHR20110822)Training Programme Foundation for the Beijing Municipal Excellent Talents (Grant No. 2010D005015000002)the Fundamental Research Foundation of Beijing University of Technology (Grant No. X4006013201101)Education Department Science Project of Hebei Province (Grant No. Z2010297)Science Project of Shijiazhuang University of Economics (Grant No. XN0912)
文摘In virtue of the notion of likelihood ratio and moment generating function, the limit properties of the sequences of absolutely continuous random variables are studied, and a class of strong limit theorems represented by inequalities with random bounds are obtained.
基金supported by the National Natural Science Foundation of China,No.81473769(to WW),81772430(to WW)a grant from the Training Program of Innovation and Entrepreneurship for Undergraduates of Southern Medical University of Guangdong Province of China in 2016,No.201612121057(to WW)
文摘OBJECTIVE: The objective of this study is to summarize and analyze the brain signal patterns of empathy for pain caused by facial expressions of pain utilizing activation likelihood estimation, a meta-analysis method. DATA SOURCES: Studies concerning the brain mechanism were searched from the Science Citation Index, Science Direct, PubMed, DeepDyve, Cochrane Library, SinoMed, Wanfang, VIP, China National Knowledge Infrastructure, and other databases, such as SpringerLink, AMA, Science Online, Wiley Online, were collected. A time limitation of up to 13 December 2016 was applied to this study. DATA SELECTION: Studies presenting with all of the following criteria were considered for study inclusion: Use of functional magnetic resonance imaging, neutral and pained facial expression stimuli, involvement of adult healthy human participants over 18 years of age, whose empathy ability showed no difference from the healthy adult, a painless basic state, results presented in Talairach or Montreal Neurological Institute coordinates, multiple studies by the same team as long as they used different raw data. OUTCOME MEASURES: Activation likelihood estimation was used to calculate the combined main activated brain regions under the stimulation of pained facial expression. RESULTS: Eight studies were included, containing 178 subjects. Meta-analysis results suggested that the anterior cingulate cortex(BA32), anterior central gyrus(BA44), fusiform gyrus, and insula(BA13) were activated positively as major brain areas under the stimulation of pained facial expression. CONCLUSION: Our study shows that pained facial expression alone, without viewing of painful stimuli, activated brain regions related to pain empathy, further contributing to revealing the brain's mechanisms of pain empathy.
文摘This in virtue of the notion of likelihood ratio and the tool of moment generating function, the limit properties of the sequences of random discrete random variables are studied, and a class of strong deviation theorems which represented by inequalities between random variables and their expectation are obtained. As a result, we obtain some strong deviation theorems for Poisson distribution and binomial distribution.
文摘In this article, we propose a generalized empirical likelihood inference for the parametric component in semiparametric generalized partially linear models with longitudinal data. Based on the extended score vector, a generalized empirical likelihood ratios function is defined, which integrates the within-cluster?correlation meanwhile avoids direct estimating the nuisance parameters in the correlation matrix. We show that the proposed statistics are asymptotically?Chi-squared under some suitable conditions, and hence it can be used to construct the confidence region of parameters. In addition, the maximum empirical likelihood estimates of parameters and the corresponding asymptotic normality are obtained. Simulation studies demonstrate the performance of the proposed method.
文摘This paper mainly addresses maximum likelihood estimation for a response-selective stratified sampling scheme, the basic stratified sampling (BSS), in which the maximum subsample size in each stratum is fixed. We derived the complete-data likelihood for BSS, and extended it as a full-data likelihood by incorporating incomplete data. We also similarly extended the empirical proportion likelihood approach for consistent and efficient estimation. We conducted a simulation study to compare these two new approaches with the existing estimation methods in BSS. Our result indicates that they perform as well as the standard full information likelihood approach. Methods were illustrated using a growth model for fish size at age, including between-individual variability. One of our major conclusions is that the fully observed BSS data, the partially observed data used for stratification, and the sampling strategy are all important in constructing a consistent and efficient estimator.
基金The MKE(The Ministry of Knowledge Economy),Korea,under the ITRC(Information Technology Research Center)support program supervised by the NIPA(National IT Industry Promotion Agency) (NIPA-2012-H0301-12-2006)Brain Research Center(BRC)(2012K001127),The MKE(10033634-2012-21)National Research Foundation of Korea(NRF)(2012-0005787)
文摘We characterize the hemodynamic response changes near-infrared spectroscopy （NIRS） during the presentation of in the main olfactory bulb （MOB） of anesthetized rats with three different odorants： （i） plain air as a reference （Blank）, （ii） 2-heptanone （HEP）, and （iii） isopropylbenzene （Ib）. Odorants generate different changes in the concentrations of oxy- hemoglobin. Our results suggest that NIRS technology might be useful in discriminating various odorants in a non-invasive manner using animals with a superb olfactory system.
文摘The likelihood function plays a central role in statistical analysis in relation to information, from both frequentist and Bayesian perspectives. In large samples several new properties of the likelihood in relation to information are developed here. The Arrow-Pratt absolute risk aversion measure is shown to be related to the Cramer-Rao Information bound. The derivative of the log-likelihood function is seen to provide a measure of information related stability for the Bayesian posterior density. As well, information similar prior densities can be defined reflecting the central role of likelihood in the Bayes learning paradigm.
文摘In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the assumption that the distribution of observations is unimodal and symmetry, this method can give the estimates of the parametric. Finally, two simulated adjustment problem are constructed to explain this method. The new method presented in this paper shows an effective way of solving the problem; the estimated values are nearer to their theoretical ones than those by least squares adjustment approach.
基金the Michigan Department of Transportation (MDOT) for the financial support of this study (report no. SPR1723)。
文摘The calibration of transfer functions is essential for accurate pavement performance predictions in the PavementME design. Several studies have used the least square approach to calibrate these transfer functions. Least square is a widely used simplistic approach based on certain assumptions. Literature shows that these least square approach assumptions may not apply to the non-normal distributions. This study introduces a new methodology for calibrating the transverse cracking and international roughness index(IRI) models in rigid pavements using maximum likelihood estimation(MLE). Synthetic data for transverse cracking, with and without variability, are generated to illustrate the applicability of MLE using different known probability distributions(exponential,gamma, log-normal, and negative binomial). The approach uses measured data from the Michigan Department of Transportation's(MDOT) pavement management system(PMS) database for 70 jointed plain concrete pavement(JPCP) sections to calibrate and validate transfer functions. The MLE approach is combined with resampling techniques to improve the robustness of calibration coefficients. The results show that the MLE transverse cracking model using the gamma distribution consistently outperforms the least square for synthetic and observed data. For observed data, MLE estimates of parameters produced lower SSE and bias than least squares(e.g., for the transverse cracking model, the SSE values are 3.98 vs. 4.02, and the bias values are 0.00 and-0.41). Although negative binomial distribution is the most suitable fit for the IRI model for MLE, the least square results are slightly better than MLE. The bias values are-0.312 and 0.000 for the MLE and least square methods. Overall, the findings indicate that MLE is a robust method for calibration, especially for non-normally distributed data such as transverse cracking.
文摘目的通过激活似然估计(ALE)的荟萃分析方法探讨感觉神经性耳聋(SNHL)病人的脑自发活动改变特点,进一步了解SNHL可能存在的脑功能损伤及重塑的神经机制。方法检索2023年8月21日之前Web of Science、PubMed、CNKI、万方医学网、中华医学期刊全文数据库中采用局部一致性(ReHo)及低频振幅/分数低频振幅(ALFF/fALFF)分析SNHL病人脑功能改变的文献,按照纳排标准对文献筛选后,采用激活似然估计法(ALE)纳入研究中SNHL病人自发脑神经活动异常的脑区进行Meta分析。结果共纳入22篇29项研究(SNHL 736例,对照487例),其中ReHo研究11项,ALFF/fALFF研究18项。联合ReHo/ALFF/fALFF分析方法且不区分耳聋侧别结果显示SNHL病人左侧丘脑背内侧核自发脑活动增加,左侧颞上回、左侧额下回岛盖部及左侧背外侧前额叶自发脑活动减低。分别依次对左/右耳SNHL病人、ReHo和ALFF/fALFF方法进行ALE分析,结果均未见任何异常活动脑区。结论运用ALE荟萃分析方法证实SNHL病人多个脑区存在自发活动异常,有助于进一步了解SNHL脑功能损伤及重塑的规律及特征,为其后续诊疗评估提供重要依据。
