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Probiotics supplementation for management of type Ⅱ diabetes risk factors in adults with polycystic ovarian syndrome: a meta-analysis of randomized clinical trial 被引量:3
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作者 Chengcheng Zhang Yingyue Sheng +7 位作者 Jinchi Jiang Yuzheng Xue Leilei Yu Fengwei Tian Jianxin Zhao Hao Zhang Jian Jin Qixiao Zhai 《Food Science and Human Wellness》 SCIE CSCD 2023年第4期1053-1063,共11页
This meta-analysis of randomized controlled trials aimed to evaluate the effects of probiotic supplementation on glucose homeostasis in patients with polycystic ovary syndrome(PCOS).The meta-analysis was performed in ... This meta-analysis of randomized controlled trials aimed to evaluate the effects of probiotic supplementation on glucose homeostasis in patients with polycystic ovary syndrome(PCOS).The meta-analysis was performed in accordance with the Cochrane Handbook guidelines and relevant the preferred reporting items for systematic reviews and meta-analyses(PRISMA)statement criteria.Of 825 identified reports,11 randomized clinical trials were included in the meta-analysis.An analysis of pooled extracted data revealed that supplementation with probiotics significantly decreased fasting blood glucose(FBG,n=7;standardized mean difference(SMD)=−0.40;95%confidence interval(CI):−2.02,−0.02;P=0.04)and insulin levels(n=6;SMD=−0.57;95%CI:−0.89,−0.25;P=0.0004)and the homeostatic model assessment of insulin resistance(n=7;SMD=−0.64;95%CI:−0.96,−0.31;P=0.0001)while increasing the quantitative insulin sensitivity check index(QUICKI,n=5;SMD=0.58;95%CI:0.08,1.09;P=0.02)in patients with PCOS.The FBG-reducing effect decreased as the baseline body mass index(BMI)and mean age of the participants increased.Indeed,a greater number of bacterial species and a higher bacterial dose were shown to reduce QUICKI effectively.The systematic review indicated that probiotic supplementation may help to control glucose homeostasis in adults with polycystic ovarian syndrome. 展开更多
关键词 Polycystic ovary syndrome Type 2 diabetes Glucose homeostasis Probiotic META-ANALYSIS randomized clinical trial
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Executive functioning in TBI from rehabilitation to social reintegration: COMPASS^(goal), a randomized controlled trial(grant: 1I01RX000637-01A3 by the VA ORD RR&D, 2013–2016) 被引量:1
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作者 Alexander V.Libin Joel Scholten +11 位作者 Manon Maitland Schladen Ellen Danford Nawar Shara Walter Penk Jordan Grafman Linda Resnik Dwan Bruner Samantha Cichon Miriam Philmon Brenda Tsai Marc Blackman Alexander Dromerick 《Military Medical Research》 SCIE CAS 2015年第4期181-200,共20页
Background: Traumatic brain injury is a major health problem that frequently leads to deficits in executive function. Self-regulation processes, such as goal-setting, may become disordered after traumatic brain injury... Background: Traumatic brain injury is a major health problem that frequently leads to deficits in executive function. Self-regulation processes, such as goal-setting, may become disordered after traumatic brain injury, particularly when the frontal regions of the brain and their connections are involved. Such impairments reduce injured veterans' ability to return to work or school and to regain satisfactory personal lives. Understanding the neurologically disabling effects of brain injury on executive function is necessary for both the accurate diagnosis of impairment and the individual tailoring of rehabilitation processes to help returning service members recover independent function.Methods/design: The COMPASSgoal(Community Participation through Self-Efficacy Skills Development) program develops and tests a novel patient-centered intervention framework for community reintegration psychosocial research in veterans with mild traumatic brain injury. COMPASSgoal integrates the principles and best practices of goal self-management. Goal setting is a core skill in self-management training by which persons with chronic health conditions learn to improve their status and decrease symptom effects. Over a three-year period, COMPASSgoal will recruit 110 participants with residual executive dysfunction three months or more post-injury. Inclusion criteria combine both clinical diagnosis and standardized scores that are >1 SD from the normative score on the Frontal Systems Rating Scale. Participants are randomized into two groups: goal-management(intervention) and supported discharge(control). The intervention is administered in eight consecutive, weekly sessions. Assessments occur at enrollment, post-intervention/supported discharge, and three months post-treatment follow-up.Discussion: Goal management is part of the "natural language" of rehabilitation. However, collaborative goal-setting between clinicians/case managers and clients can be hindered by the cognitive deficits that follow brain injury. Re-training returning veterans with brain injury in goal management, with appropriate help and support, would essentially treat deficits in executive function. A structured approach to goal self-management may foster greater independence and self-efficacy, help veterans gain insight into goals that are realistic for them at a given time, and help clinicians and veterans to work more effectively as true collaborators. 展开更多
关键词 Executive function Traumatic brain injury GOAL-SETTING Community reintegration VETERANS randomized controlled trial Manualized psychosocial intervention
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Randomized Algorithms for Probabilistic Optimal Robust Performance Controller Design 被引量:1
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作者 宋春雷 谢玲 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期15-19,共5页
Polynomial-time randomized algorithms were constructed to approximately solve optimal robust performance controller design problems in probabilistic sense and the rigorous mathematical justification of the approach wa... Polynomial-time randomized algorithms were constructed to approximately solve optimal robust performance controller design problems in probabilistic sense and the rigorous mathematical justification of the approach was given. The randomized algorithms here were based on a property from statistical learning theory known as (uniform) convergence of empirical means (UCEM). It is argued that in order to assess the performance of a controller as the plant varies over a pre-specified family, it is better to use the average performance of the controller as the objective function to be optimized, rather than its worst-case performance. The approach is illustrated to be efficient through an example. 展开更多
关键词 randomized algorithms statistical learning theory uniform convergence of empirical means (UCEM) probabilistic optimal robust performance controller design
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Current situation on the reporting quality of randomized controlled trials in 5 leading Chinese medical journals 被引量:1
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作者 Xu Wei Li Tiejun Wu Cheng 《Journal of Medical Colleges of PLA(China)》 CAS 2009年第2期105-111,共7页
Objective:The Consolidated Standards for Reporting of Trials(CONSORT) statement has already proved to be an efficient standard for reporting quality of randomized controlled trials(RCTs).However,most of the Chinese me... Objective:The Consolidated Standards for Reporting of Trials(CONSORT) statement has already proved to be an efficient standard for reporting quality of randomized controlled trials(RCTs).However,most of the Chinese medical journals have not endorsed the CONSORT statement.The current situation about the reporting quality of RCTs in Chinese medical journals is still unclear.The purpose of the study was to evaluate the reporting quality of RCTs on papers published in 5 leading Chinese medical journals.Methods:We evaluated 232 original RCT papers using a reporting quality scale based on CONSORT statement from 2001 to 2006 in 5 Chinese medical journals(Journal type 1) without adoption of CONSORT and Chinese Journal of Evidence-based Medicine(Journal type 2) which adopted CONSORT in 2004.We measured the inclusion of 26 items for the reporting quality scale and 6 core items of each RCT report,gave score to each item and calculated the total score obtained in each report and the proportion of reports including individual items.The reporting quality of RCT trials from 2001 to 2003(pre-adoption period) was compared with that from 2004 to 2006(post-adoption period).Results:The average reporting quality of RCTs was moderate(mean score,15.18),and the mean score of the 6 core items was low(mean score,1.09) in 5 leading journals.The difference in the total score and the score of the 6 core items between pre-adoption period(2001-2003) and post-adoption period(2004-2006) was statistically significant(P=0.003;P=0.000).Interaction between journal type and period was not significant(F=0.76;P=0.383).We concluded that the change tendency of reporting quality between Journal type 1 and 2 was not different.But as to the core items of sequence concealment and intention-to-treat analysis,the increases were greater for Journal type 2 when evaluated against Journal type 1(P=0.038;P=0.016).Conclusion:The reporting quality of RCT trials in 5 leading Chinese medical journals is improving.However,the lack of important items in RCT trials remains a serious problem.We recommend the endorsement of the Consolidated Standards for Reporting of Trials statement in Chinese medical journals and the continuing education on evidence-based medicine in China. 展开更多
关键词 randomized controlled trials CONSORT Evidence-based Medicine
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A Regularized Randomized Kaczmarz Algorithm for Large Discrete Ill-Posed Problems
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作者 LIU Fengming WANG Zhengsheng +1 位作者 YANG Siyu XU Guili 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第5期787-795,共9页
Tikhonov regularization is a powerful tool for solving linear discrete ill-posed problems.However,effective methods for dealing with large-scale ill-posed problems are still lacking.The Kaczmarz method is an effective... Tikhonov regularization is a powerful tool for solving linear discrete ill-posed problems.However,effective methods for dealing with large-scale ill-posed problems are still lacking.The Kaczmarz method is an effective iterative projection algorithm for solving large linear equations due to its simplicity.We propose a regularized randomized extended Kaczmarz(RREK)algorithm for solving large discrete ill-posed problems via combining the Tikhonov regularization and the randomized Kaczmarz method.The convergence of the algorithm is proved.Numerical experiments illustrate that the proposed algorithm has higher accuracy and better image restoration quality compared with the existing randomized extended Kaczmarz(REK)method. 展开更多
关键词 ill-posed problem Tikhonov regularization randomized extended Kaczmarz(REK)algorithm image restoration
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Prenatal multiple micronutrient-fortified balanced energy-protein supplementation and newborn telomere length and mitochondrial DNA content:a randomized controlled efficacy trial in rural Burkina Faso
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作者 Giles T.Hanley-Cook Yuri Bastos-Moreira +12 位作者 Dries S.Martens Trenton Dailey-Chwalibóg Laeticia Celine Toe Brenda de Kok Lionel OIivier Ouédraogo Alemayehu Argaw Kokeb Tesfamariam Patrick Kolsteren Lieven Huybregts Tim S.Nawrot Sarah De Saeger Marthe De Boevre Carl Lachat 《Food Science and Human Wellness》 2025年第4期1387-1397,共11页
Background:Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes.The effect on markers of health and disease,such as offspring telomere length... Background:Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes.The effect on markers of health and disease,such as offspring telomere length(TL)and mitochondrial DNA content(mtDNAc)is unknown.Objectives:We assessed the efficacy of maternal multiple micronutrient(MMN)-fortified balanced-energy protein(BEP)and iron-folic acid(IFA)supplementation on newborn TL as a secondary outcome and mtDNAc as a non-declared outcome.Design:We conducted a randomized controlled trial in rural Burkina Faso,among pregnant females(15-40 years old)enrolled at<21 weeks of gestation.Mothers received either MMN-fortified BEP and IFA(intervention)or IFA only(control)throughout pregnancy.Whole arterial blood samples were collected from the umbilical cord of 104 control and 90 intervention group infants,respectively.Average relative TL and mtDNAc were measured using quantitative polymerase chain reaction.Linear regression models were fitted to assess TL and mtDNAc differences across trial arms.Results:We found that a combined daily MMN-fortified BEP supplement and IFA tablet did not affect newborn TL[β=-0.010(95%CI:-0.057,0.036);P=0.662]or mtDNAc[β=0.065(95%CI:-0.203,0.073);P=0.354],as compared to an IFA tablet alone.These findings were confirmed(P>0.05)by adjusting the regression models for potential prognostic factors of study outcomes at enrollment.Exploratory analyses indicated higher,but non-significantly different mtDNAc among children born either small-for-gestational age,low birthweight,or preterm.Conclusion:Newborns from mothers who received daily nutritional supplements across gestation did not have different relative TL or mtDNAc. 展开更多
关键词 Balanced-energy protein Burkina Faso Iron-folic acid Mitochondrial DNA Multiple micronutrients randomized controlled trial Telomere length
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Asymptotic Probability of Record Numbers in Random Walks
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作者 PENG Wenjie LI Yuqiang 《应用概率统计》 北大核心 2025年第1期17-27,共11页
In this paper,large deviations principle(LDP)and moderate deviations principle(MDP)of record numbers in random walks are studied under certain conditions.The results show that the rate functions of LDP and MDP are dif... In this paper,large deviations principle(LDP)and moderate deviations principle(MDP)of record numbers in random walks are studied under certain conditions.The results show that the rate functions of LDP and MDP are different from those of weak record numbers,which are interesting complements of the conclusions by Li and Yao[1]. 展开更多
关键词 random walk record number large deviation moderate deviation
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Effects of dietary olive oil, camellia seed oil and soybean oil on serum lipid composition in women with a high risk of cardiovascular disease: a lipidomic analysis
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作者 Minyu Wu Changfeng Hu Lirong Shen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3193-3201,共9页
Numerous studies currently compare the lipid metabolism in patients with cardiovascular disease(CVD)and healthy individuals to identify lipid markers for predicting CVD.In this study,multidimensional mass spectrometry... Numerous studies currently compare the lipid metabolism in patients with cardiovascular disease(CVD)and healthy individuals to identify lipid markers for predicting CVD.In this study,multidimensional mass spectrometry-based shotgun lipidomics was used to examine the serum lipidomics of participants in a clinical randomized controlled feeding trial undergoing olive oil(OO),camellia seed oil(CSO),and soybean oil(SO)dietary interventions.189 lipid molecules are identified,including 14 species of phosphatidylinositol,45 species of ethanolamine glycerols(PE),47 species of choline glycerophospholipids(PC),39 species of triacylglycerols(TAG),18 species of lysophosphatidylcholine,and 26 species of sphingomyelin.After screening,10 lipid markers are found,among which 18:2 fatty acid(FA),16:1 FA,C54:4/C55:11,C54:3/C55:10,and C52:3/C53:10 in TAG pool,p18:0/20:0 and a18:0/18:1 in PC pool,and p18:1/20:4 in PE pool have differential regulation in the SO group compared to OO and CSO.The d16:0/18:1 in PC pool and C52:2/C53:9 in TAG pool are differentially regulated by OO and CSO.The C52:2/C53:9 in TAG pool has a significant negative correlation with aspartate aminotransferase(r=-0.363,P=0.048)and high-density lipoprotein cholesterol(r=-0.519,P<0.01).This study provides a reference for researching the effect of dietary fat on blood lipid metabolism. 展开更多
关键词 Lipidomic analysis randomized controlled feeding trial Monounsaturated fatty acid n-6 Polyunsaturated fatty acid Cardiometabolic profile
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A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm 被引量:1
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作者 Tie Yan Rui Xu +2 位作者 Shi-Hui Sun Zhao-Kai Hou Jin-Yu Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1135-1148,共14页
Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face ... Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation. 展开更多
关键词 Intelligent drilling Closed-loop drilling Lithology identification Random forest algorithm Feature extraction
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Evolution, resilience and causes of global petroleum gas trade networks: 1995-2020 被引量:1
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作者 Na Li Yi-Ran Song +1 位作者 Ying Wang Chun-Bao Ge 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3656-3674,共19页
Based on the HS 4-digit code trade data in UNCOMTRADE from 1995 to 2020, this paper analyzes the characteristics of the evolution of the global PG trade network using the complex network approach and analyzes the chan... Based on the HS 4-digit code trade data in UNCOMTRADE from 1995 to 2020, this paper analyzes the characteristics of the evolution of the global PG trade network using the complex network approach and analyzes the changes in its resilience at the overall and country levels, respectively. The results illustrated that:(1) The scale of the global PG trade network tends to expand, and the connection is gradually tightened, experiencing a change from a “supply-oriented” to a “supply-and-demand” pattern, in which the U.S., Russia, Qatar, and Australia have gradually replaced Canada, Japan, and Russia to become the core trade status, while OPEC countries such as Qatar, Algeria, and Kuwait mainly rely on PG exports to occupy the core of the global supply, and the trade status of other countries has been dynamically alternating and evolving.(2) The resilience of the global PG trade network is lower than that of the random network and decreases non-linearly with more disrupted countries. Moreover, the impact of the U.S. is more significant than the rest of countries. Simulations using the exponential random graph model(ERGM) model revealed that national GDP, institutional quality, common border and RTA network are the determinants of PG trade network formation, and the positive impact of the four factors not only varies significantly across regions and stages, but also increases with national network status. 展开更多
关键词 Petroleum gas Complex network approach Network resilience Exponential random graph model
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Deblurring,artifact-free optical coherence tomography with deconvolution-random phase modulation 被引量:1
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作者 Xin Ge Si Chen +4 位作者 Kan Lin Guangming Ni En Bo Lulu Wang Linbo Liu 《Opto-Electronic Science》 2024年第1期13-24,共12页
Deconvolution is a commonly employed technique for enhancing image quality in optical imaging methods.Unfortu-nately,its application in optical coherence tomography(OCT)is often hindered by sensitivity to noise,which ... Deconvolution is a commonly employed technique for enhancing image quality in optical imaging methods.Unfortu-nately,its application in optical coherence tomography(OCT)is often hindered by sensitivity to noise,which leads to ad-ditive ringing artifacts.These artifacts considerably degrade the quality of deconvolved images,thereby limiting its effect-iveness in OCT imaging.In this study,we propose a framework that integrates numerical random phase masks into the deconvolution process,effectively eliminating these artifacts and enhancing image clarity.The optimized joint operation of an iterative Richardson-Lucy deconvolution and numerical synthesis of random phase masks(RPM),termed as De-conv-RPM,enables a 2.5-fold reduction in full width at half-maximum(FWHM).We demonstrate that the Deconv-RPM method significantly enhances image clarity,allowing for the discernment of previously unresolved cellular-level details in nonkeratinized epithelial cells ex vivo and moving blood cells in vivo. 展开更多
关键词 DECONVOLUTION random phase masks DEBLURRING
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一种基于KMeans与Random Forest的异常温升捕捉方法
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作者 汪海良 《现代建筑电气》 2024年第6期21-26,49,共7页
针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线... 针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线路,预防火灾的发生。 展开更多
关键词 线路过载 异常温升 Random Forest KMeans
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OFDMA-Based Unsourced Random Access in LEO Satellite Internet of Things
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作者 Jiaqi Fang Gangle Sun +2 位作者 Wenjin Wang Li You Rui Ding 《China Communications》 SCIE CSCD 2024年第1期13-23,共11页
This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform plana... This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform planar array(UPA)is equipped on the satellite.In LEO satellite communications,unavoidable timing and frequency offsets cause phase shifts in the transmitted signals,substantially diminishing the decoding performance of current terrestrial CCS URA receiver.To cope with this issue,we expand the inner codebook with predefined timing and frequency offsets and formulate the inner decoding as a tractable compressed sensing(CS)problem.Additionally,we leverage the inherent sparsity of the UPA-equipped LEO satellite angular domain channels,thereby enabling the outer decoder to support more active devices.Furthermore,the outputs of the outer decoder are used to reduce the search space of the inner decoder,which cuts down the computational complexity and accelerates the convergence of the inner decoding.Simulation results verify the effectiveness of the proposed scheme. 展开更多
关键词 LEO OFDMA SATELLITE unsourced random access UPA
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ESTIMATION OF AVERAGE DIFFERENTIAL ENTROPY FOR A STATIONARY ERGODIC SPACE-TIME RANDOM FIELD ON A BOUNDED AREA
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作者 Zhanjie SONG Jiaxing ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1984-1996,共13页
In this paper,we mainly discuss a discrete estimation of the average differential entropy for a continuous time-stationary ergodic space-time random field.By estimating the probability value of a time-stationary rando... In this paper,we mainly discuss a discrete estimation of the average differential entropy for a continuous time-stationary ergodic space-time random field.By estimating the probability value of a time-stationary random field in a small range,we give an entropy estimation and obtain the average entropy estimation formula in a certain bounded space region.It can be proven that the estimation of the average differential entropy converges to the theoretical value with a probability of 1.In addition,we also conducted numerical experiments for different parameters to verify the convergence result obtained in the theoretical proofs. 展开更多
关键词 differential entropy STATIONARY ERGODICITY space-time random field time series
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Deciphering nitrogen concentrations in Metasequoia glyptostroboides : a novel approach using RGB images and machine learning
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作者 Cong Ma Ran Tong +4 位作者 Nianfu Zhu Wenwen Yuan Yanji Li GGeoff Wang Tonggui Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期110-120,共11页
Recent advances in spectral sensing techniques and machine learning(ML)methods have enabled the estimation of plant physiochemical traits.Nitrogen(N)is a primary limiting factor for terrestrial forest growth,but tradi... Recent advances in spectral sensing techniques and machine learning(ML)methods have enabled the estimation of plant physiochemical traits.Nitrogen(N)is a primary limiting factor for terrestrial forest growth,but traditional methods for N determination are labor-intensive,time-consuming,and destructive.In this study,we present a rapid,non-destructive method to predict leaf N concentration(LNC)in Metasequoia glyptostroboides plantations under N and phosphorus(P)fertilization using ML techniques and unmanned aerial vehicle(UAV)-based RGB(red,green,blue)images.Nine spectral vegetation indices(VIs)were extracted from the RGB images.The spectral reflectance and VIs were used as input features to construct models for estimating LNC based on support vector machine,ran-dom forest(RF),and multiple linear regression,gradient boosting regression and classification and regression trees(CART).The results show that RF is the best fitting model for estimating LNC with a coefficient of determination(R2)of 0.73.Using this model,we evaluated the effects of N and P treatments on LNC and found a significant increase with N and a decrease with P.Height,diameter at breast height(DBH),and crown width of all M.glyptostroboides were analyzed by Pearson correlation with the predicted LNC.DBH was significantly correlated with LNC under N treat-ment.Our results highlight the potential of combining UAV RGB images with an ML algorithm as an efficient,scalable,and cost-effective method for LNC quantification.Future research can extend this approach to different tree species and different plant traits,paving the way for large-scale,time-efficient plant growth monitoring. 展开更多
关键词 RGB images Random forest LNC N and P addition METASEQUOIA
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ON THE EMPTY BALLS OF A CRITICAL OR SUBCRITICAL BRANCHING RANDOM WALK
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作者 Shuxiong ZHANG Jie XIONG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期2051-2072,共22页
Let{Z_(n)}_(n)≥0 be a critical or subcritical d-dimensional branching random walk started from a Poisson random measure whose intensity measure is the Lebesugue measure on R^(d).Denote by R_(n):=sup{u>0:Z_(n)({x∈... Let{Z_(n)}_(n)≥0 be a critical or subcritical d-dimensional branching random walk started from a Poisson random measure whose intensity measure is the Lebesugue measure on R^(d).Denote by R_(n):=sup{u>0:Z_(n)({x∈R^(d):∣x∣<u})=0}the radius of the largest empty ball centered at the origin of Z_(n).In this work,we prove that after suitable renormalization,Rn converges in law to some non-degenerate distribution as n→∞.Furthermore,our work shows that the renormalization scales depend on the offspring law and the dimension of the branching random walk.This completes the results of Révész[13]for the critical binary branching Wiener process. 展开更多
关键词 empty ball DIMENSION branching random walk super-Brownian motion
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Pedestrian flow through exit:Study focused on evacuation pattern
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作者 张博思 余志红 +2 位作者 孙柏林 郭紫钰 陈默 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期755-764,共10页
Experiments are conducted on the evacuation rate of pedestrians through exits with queued evacuation pattern and random evacuation pattern. The experimental results show that the flow rate of pedestrians is larger wit... Experiments are conducted on the evacuation rate of pedestrians through exits with queued evacuation pattern and random evacuation pattern. The experimental results show that the flow rate of pedestrians is larger with the random evacuation pattern than with the queued evacuation pattern. Therefore, the exit width calculated based on the minimum evacuation clear width for every 100 persons, which is on the assumption that the pedestrians pass through the exit in one queue or several queues, is conservative. The number of people crossing the exit simultaneously is greater in the random evacuation experiments than in the queued evacuation experiments, and the time interval between the front row and rear row of people is shortened in large-exit conditions when pedestrians evacuate randomly. The difference between the flow rate with a queued evacuation pattern and the flow rate with a random evacuation pattern is related to the surplus width of the exit, which is greater than the total width of all accommodated people streams. Two dimensionless quantities are defined to explore this relationship. It is found that the difference in flow rate between the two evacuation patterns is stable at a low level when the surplus width of the exit is no more than 45% of the width of a single pedestrian stream. There is a great difference between the flow rate with the queued evacuation pattern and the flow rate with the random evacuation pattern in a scenario with a larger surplus width of the exit. Meanwhile, the pedestrians crowd extraordinarily at the exit in these conditions as well, since the number of pedestrians who want to evacuate through exit simultaneously greatly exceeds the accommodated level. Therefore, the surplus width of exit should be limited especially in the narrow exit condition, and the relationship between the two dimensionless quantities mentioned above could provide the basis to some extent. 展开更多
关键词 EVACUATION exit width flow rate queued evacuation pattern random evacuation pattern
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Spatial search weighting information contained in cell velocity distribution
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作者 马一凯 李娜 陈唯 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期522-528,共7页
Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell ... Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication. 展开更多
关键词 cell migration foraging efficiency random walk spatial search weight
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Random vibration analysis of FGM plates subjected to moving load using a refined stochastic finite element method
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作者 Ngoc-Tu Do Trung Thanh Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期42-56,共15页
The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte C... The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte Carlo simulation(MCS), so-called refined stochastic finite element method to investigate the random vibration of functionally graded material(FGM) plates subjected to the moving load.The advantage of the proposed method is to use r-FSDT to improve the accuracy of classical FSDT, satisfy the stress-free condition at the plate boundaries, and combine with MCS to analyze the vibration of the FGM plate when the parameter inputs are random quantities following a normal distribution. The obtained results show that the distribution characteristics of the vibration response of the FGM plate depend on the standard deviation of the input parameters and the velocity of the moving load.Furthermore, the numerical results in this study are expected to contribute to improving the understanding of FGM plates subjected to moving loads with uncertain input parameters. 展开更多
关键词 FGM Moving load R-FSDT Q4 element Monte Carlo simulation Random vibration
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Imaging through scattering layers using a near-infrared low-spatial-coherence fiber random laser
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作者 Anda Shi Zeyu Wang +2 位作者 Chenxi Duan Zhao Wang Weili Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期226-232,共7页
Optical memory effect-based speckle-correlated technology has been developed for reconstructing hidden objectsfrom disordered speckle patterns,achieving imaging through scattering layers.However,the lighting efficienc... Optical memory effect-based speckle-correlated technology has been developed for reconstructing hidden objectsfrom disordered speckle patterns,achieving imaging through scattering layers.However,the lighting efficiency and fieldof view of existing speckle-correlated imaging systems are limited.Here,a near-infrared low spatial coherence fiberrandom laser illumination method is proposed to address the above limitations.Through the utilization of random Rayleighscattering within dispersion-shifted fibers to provide feedback,coupled with stimulated Raman scattering for amplification,a near-infrared fiber random laser exhibiting a high spectral density and extremely low spatial coherence is generated.Based on the designed fiber random laser,speckle-correlated imaging through scattering layers is achieved,with highlighting efficiency and a large imaging field of view.This work improves the performance of speckle-correlated imagingand enriches the research on imaging through scattering medium. 展开更多
关键词 fiber random laser speckle-correlated imaging scattering medium spatial coherence
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