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Two-Order Approximate and Large Stepsize Numerical Direction Based on the Quadratic Hypothesis and Fitting Method 被引量:3
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作者 Xiaoli Yin Chunming Li Yuan Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第3期901-909,共9页
Many effective optimization algorithms require partial derivatives of objective functions,while some optimization problems'objective functions have no derivatives.According to former research studies,some search d... Many effective optimization algorithms require partial derivatives of objective functions,while some optimization problems'objective functions have no derivatives.According to former research studies,some search directions are obtained using the quadratic hypothesis of objective functions.Based on derivatives,quadratic function assumptions,and directional derivatives,the computational formulas of numerical first-order partial derivatives,second-order partial derivatives,and numerical second-order mixed partial derivatives were constructed.Based on the coordinate transformation relation,a set of orthogonal vectors in the fixed coordinate system was established according to the optimization direction.A numerical algorithm was proposed,taking the second order approximation direction as an example.A large stepsize numerical algorithm based on coordinate transformation was proposed.Several algorithms were validated by an unconstrained optimization of the two-dimensional Rosenbrock objective function.The numerical second order approximation direction with the numerical mixed partial derivatives showed good results.Its calculated amount is 0.2843%of that of without second-order mixed partial derivative.In the process of rotating the local coordinate system 360°,because the objective function is more complex than the quadratic function,if the numerical direction derivative is used instead of the analytic partial derivative,the optimization direction varies with a range of 103.05°.Because theoretical error is in the numerical negative gradient direction,the calculation with the coordinate transformation is 94.71%less than the calculation without coordinate transformation.If there is no theoretical error in the numerical negative gradient direction or in the large-stepsize numerical optimization algorithm based on the coordinate transformation,the sawtooth phenomenon occurs.When each numerical mixed partial derivative takes more than one point,the optimization results cannot be improved.The numerical direction based on the quadratic hypothesis only requires the objective function to be obtained,but does not require derivability and does not take into account truncation error and rounding error.Thus,the application scopes of many optimization methods are extended. 展开更多
关键词 Directional derivative numerical differential optimization method quadratic function hypothesis
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Application of Reciting Methods on Secondary School Oral English Learning — based on Krashen's Input Hypothesis
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作者 严佳佳 《海外英语》 2015年第20期228-230,共3页
It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypoth... It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypothesis. Through analyzing the influencing factors of oral English learning and the significance of reciting methods, the article explored the concrete reciting methods. I hope it will shed some light on the English teaching and learning practice. 展开更多
关键词 SECONDARY SCHOOL students ORAL English Input hypothesis reciting methodS
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Particle flters for probability hypothesis density flter with the presence of unknown measurement noise covariance 被引量:9
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作者 Wu Xinhui Huang Gaoming Gao Jun 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第6期1517-1523,共7页
In Bayesian multi-target fltering,knowledge of measurement noise variance is very important.Signifcant mismatches in noise parameters will result in biased estimates.In this paper,a new particle flter for a probabilit... In Bayesian multi-target fltering,knowledge of measurement noise variance is very important.Signifcant mismatches in noise parameters will result in biased estimates.In this paper,a new particle flter for a probability hypothesis density(PHD)flter handling unknown measurement noise variances is proposed.The approach is based on marginalizing the unknown parameters out of the posterior distribution by using variational Bayesian(VB)methods.Moreover,the sequential Monte Carlo method is used to approximate the posterior intensity considering non-linear and non-Gaussian conditions.Unlike other particle flters for this challenging class of PHD flters,the proposed method can adaptively learn the unknown and time-varying noise variances while fltering.Simulation results show that the proposed method improves estimation accuracy in terms of both the number of targets and their states. 展开更多
关键词 Multi-target tracking(MTT) Parameter estimation Probability hypothesis density Sequential Monte Carlo Variational Bayesian method
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Hypothesis Testing of Population Percentiles via the Wald Test with Bootstrap Variance Estimates
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作者 William D. Johnson Jacob E. Romer 《Open Journal of Statistics》 2016年第1期14-24,共11页
Testing the equality of percentiles (quantiles) between populations is an effective method for robust, nonparametric comparison, especially when the distributions are asymmetric or irregularly shaped. Unlike global no... Testing the equality of percentiles (quantiles) between populations is an effective method for robust, nonparametric comparison, especially when the distributions are asymmetric or irregularly shaped. Unlike global nonparametric tests for homogeneity such as the Kolmogorv-Smirnov test, testing the equality of a set of percentiles (i.e., a percentile profile) yields an estimate of the location and extent of the differences between the populations along the entire domain. The Wald test using bootstrap estimates of variance of the order statistics provides a unified method for hypothesis testing of functions of the population percentiles. Simulation studies are conducted to show performance of the method under various scenarios and to give suggestions on its use. Several examples are given to illustrate some useful applications to real data. 展开更多
关键词 BOOTSTRAP hypothesis Testing Nonparametric methods Percentile Profiles Wald Test
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Riemann Hypothesis, Catholic Information and Potential of Events with New Techniques for Financial and Other Applications
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作者 Prodromos Char. Papadopoulos 《Advances in Pure Mathematics》 2021年第5期524-572,共49页
In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic... In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic (general) Logical Propositions (<img src="Edit_5f13a4a5-abc6-4bc5-9e4c-4ff981627b2a.png" width="33" height="21" alt="" />) which will true for every element of a set A. We will study the Riemann Hypothesis in two stages: a) By using the EP we will prove that the distribution of events e (even) and o (odd) of Square Free Numbers (SFN) on the axis Ax(N) of naturals is Heads-Tails (H-T) type. b) By using the CI we will explain the way that the distribution of prime numbers can be correlated with the non-trivial zeros of the function ζ(s) of Riemann. The Introduction and the Chapter 2 are necessary for understanding the solution. In the Chapter 3 we will present a simple method of forecasting in many very useful applications (e.g. financial, technological, medical, social, etc) developing a generalization of this new, proven here, theory which we finally apply to the solution of RH. The following Introduction as well the Results with the Discussion at the end shed light about the possibility of the proof of all the above. The article consists of 9 chapters that are numbered by 1, 2, …, 9. 展开更多
关键词 Twin Problem Twin’s Problem Unsolved Mathematical Problems Prime Number Problems Millennium Problems Riemann hypothesis Riemann’s hypothesis Number Theory Information Theory Probabilities Statistics Management Financial Applications Arithmetical Analysis Optimization Theory Stock Exchange Mathematics Approximation methods Manifolds Economical Mathematics Random Variables Space of Events Strategy Games Probability Density Stock Market Technical Analysis Forecasting
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On Application of Output-Driven Hypothesis on College English Teaching
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作者 WANG Li 《Sino-US English Teaching》 2015年第7期485-490,共6页
This paper discusses how college English teaching can be carried out based on the output-driven hypothesis. It consists of three sections. Section one briefly describes the views of the output-driven hypothesis with r... This paper discusses how college English teaching can be carried out based on the output-driven hypothesis. It consists of three sections. Section one briefly describes the views of the output-driven hypothesis with relevant theoretical explanations. Section two further illustrates how such teaching practice can be conducted in terms of the teaching objectives, teaching procedures, and methods, and assessment focuses. Section three points out the potential challenges faced by university English teachers when the hypothesis is tested 展开更多
关键词 output-driven hypothesis college English teaching teaching objectives teaching procedures and methods ASSESSMENT
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Sensitivity and Specificity Analysis Relation to Statistical Hypothesis Testing and Its Errors: Application to Cryptosporidium Detection Techniques
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作者 Emmanuel de-Graft Johnson Owusu-Ansah Angelina Sampson +1 位作者 Amponsah K. Samuel Abaidoo Robert 《Open Journal of Applied Sciences》 2016年第4期209-216,共8页
The use of Statistical Hypothesis Testing procedure to determine type I and type II errors was linked to the measurement of sensitivity and specificity in clinical trial test and experimental pathogen detection techni... The use of Statistical Hypothesis Testing procedure to determine type I and type II errors was linked to the measurement of sensitivity and specificity in clinical trial test and experimental pathogen detection techniques. A theoretical analysis of establishing these types of errors was made and compared to determination of False Positive, False Negative, True Positive and True Negative. Experimental laboratory detection methods used to detect Cryptosporidium spp. were used to highlight the relationship between hypothesis testing, sensitivity, specificity and predicted values. The study finds that, sensitivity and specificity for the two laboratory methods used for Cryptosporidium detection were low hence lowering the probability of detecting a “false null hypothesis” for the presence of cryptosporidium in the water samples using either Microscopic or PCR. Nevertheless, both procedures for cryptosporidium detection had higher “true negatives” increasing its probability of failing to reject a “true null hypothesis” with specificity of 1.00 for both Microscopic and PCR laboratory detection methods. 展开更多
关键词 Sensitivity SPECIFICITY Type I and II Errors Detection methods hypothesis Testing
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A TIME DOMAIN METHOD FOR QUASI-STATIC ANALYSIS OF VISCOELASTIC THIN PLATES 被引量:2
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作者 张能辉 程昌钧 《应用数学和力学》 EI CSCD 北大核心 2001年第10期1001-1008,共8页
Based on the Boltzmann’s superposition principles of linear viscoelastic materials and the von K*-rm*-n’s hypotheses of thin plates with large deflections, a mathematical model for quasi-static problems of viscoelas... Based on the Boltzmann’s superposition principles of linear viscoelastic materials and the von K*-rm*-n’s hypotheses of thin plates with large deflections, a mathematical model for quasi-static problems of viscoelastic thin plates was given. By the Galerkin method in spatial domain, the original integro-partial-differential system could be transformed into an integral system. The latter further was reduced to a differential system by using the new method for temporal domain presented in this paper. Numerical results show that compared with the ordinary finite difference method, the new method in this paper is simpler to operate and has some advantages, such as, no storage and quicker computational speed etc. 展开更多
关键词 粘弹性薄板 von Kármán假设 GALERKIN方法 准静态响应 直接法 积分微分方程 粘弹性材料 时域算法
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Analysis and optimization of the applicability of hypothesis testing methods
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作者 Sirui Zhang 《Advances in Operation Research and Production Management》 2025年第2期75-78,共4页
With the continuous development of science and technology and other fields in today's world,statistical analysis and research have become indispensable research methods in people's daily lives.Among these,hypo... With the continuous development of science and technology and other fields in today's world,statistical analysis and research have become indispensable research methods in people's daily lives.Among these,hypothesis testing plays an important role in fields such as biology,medicine,and economics,and has significant effects in most scenarios.However,the suitability and effectiveness of different hypothesis testing methods vary depending on the context,often leading to different outcomes and levels of accuracy.This paper focuses on discussing various hypothesis testing methods in statistics,such as t-test,chi-square test,z-test,F-test,etc.In addition,this study analyzes various cases in real life and optimize and improve some hypothesis testing methods.Based on a review of existing literature,the study explores how traditional hypothesis testing determines statistical significance—where the null hypothesis is rejected if the test statistic falls within the rejection region.To improve and enhance the determination of the significance level,handle uncertainty,and increase the sample size,this paper proposes alternative methods such as NHST test,Bayesian test,big data sequential test,and failure rate hypothesis test from the perspectives of medicine and kinesiology. 展开更多
关键词 hypothesis testing applicability analysis significance test index evaluation method multiple hypothesis testing
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A TIME DOMAIN METHOD FOR QUASI-STATIC ANALYSIS OF VISCOELASTIC THIN PLATES 被引量:2
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作者 ZHANG Neng-hui(张能辉) +1 位作者 CHENG Chang-jun(程昌钧) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1109-1117,共9页
Based on the Boltzmann's superposition principles of linear viscoelastic materials and the von Karman's hypotheses of thin plates with large deflections, a mathematical model for quasi-static problems of visco... Based on the Boltzmann's superposition principles of linear viscoelastic materials and the von Karman's hypotheses of thin plates with large deflections, a mathematical model for quasi-static problems of viscoelastic thin plates was given. By the Galerkin method in spatial domain, the original integro-partial-differential system could be transformed into an integral system. The latter further was reduced to a differential system by using the new method for temporal domain presented in this paper. Numerical results show that compared with the ordinary finite difference method, the new method in this paper is simpler to operate and has some advantages, such as, no storage and quicker computational speed etc. 展开更多
关键词 viscoelastic thin plate von Karman's hypothesis Galerkin method quasistatic response direct method integro-differential equation
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A MODIFICATION OF TAYLOR-GALERKIN FINITE ELEMENT METHOD AND ITS APPLICATION 被引量:2
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作者 朱刚 谷传纲 胡庆康 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第12期1173-1179,共7页
Two basic hypothesises of Taylor-Galerkin Finite Element Method are studied in this paper. One of them which is unreasonable is redefined. The only hypothesis becomes the standpoint of Generalized Finite Element. We u... Two basic hypothesises of Taylor-Galerkin Finite Element Method are studied in this paper. One of them which is unreasonable is redefined. The only hypothesis becomes the standpoint of Generalized Finite Element. We use this idea to analysis stream function-vorticity equations with Modified Taylor-Galerkin Finite Element Method, and give the two-step solving method, which makes the solving process more reasonable than ever before. Several computational examples reveal that the results of this new method are satisfied. 展开更多
关键词 hypothesis finite element method stream function iteration
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Programming Logic Modeling and Cross-Program Defect Detection Method for Object-Oriented Code
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作者 Yan Liu Wenyuan Fang +2 位作者 Qiang Wei Yuan Zhao Liang Wang 《Computers, Materials & Continua》 SCIE EI 2020年第7期273-295,共23页
Code defects can lead to software vulnerability and even produce vulnerability risks.Existing research shows that the code detection technology with text analysis can judge whether object-oriented code files are defec... Code defects can lead to software vulnerability and even produce vulnerability risks.Existing research shows that the code detection technology with text analysis can judge whether object-oriented code files are defective to some extent.However,these detection techniques are mainly based on text features and have weak detection capabilities across programs.Compared with the uncertainty of the code and text caused by the developer’s personalization,the programming language has a stricter logical specification,which reflects the rules and requirements of the language itself and the developer’s potential way of thinking.This article replaces text analysis with programming logic modeling,breaks through the limitation of code text analysis solely relying on the probability of sentence/word occurrence in the code,and proposes an object-oriented language programming logic construction method based on method constraint relationships,selecting features through hypothesis testing ideas,and construct support vector machine classifier to detect class files with defects and reduce the impact of personalized programming on detection methods.In the experiment,some representative Android applications were selected to test and compare the proposed methods.In terms of the accuracy of code defect detection,through cross validation,the proposed method and the existing leading methods all reach an average of more than 90%.In the aspect of cross program detection,the method proposed in this paper is superior to the other two leading methods in accuracy,recall and F1 value. 展开更多
关键词 method constraint relationship programming logic code defect hypothesis test
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The Influence of "i+ 1" on Chinese Foreign Language Teaching Methods
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作者 WANG Yan 《Sino-US English Teaching》 2017年第8期483-488,共6页
"Monitor Model" explains the process and its situation from five different parts: the acquisition/learning,monitor, natural order, input, and affective filter. The Input Hypothesis, as one part of"Monitor Model" ... "Monitor Model" explains the process and its situation from five different parts: the acquisition/learning,monitor, natural order, input, and affective filter. The Input Hypothesis, as one part of"Monitor Model" proposedby Stephen D. Krashen, suggests that the comprehensible input plays a key role in the language acquisition.Nowadays, the Input Hypothesis, with "i+l" as its core proposal, influences Chinese foreign language teachingfrom various aspects. But there are also many disputes. In this paper, the author intends to elaborate on its maincontents, characteristics, influences on foreign language teaching, existing defects, and so on, aiming to achieve thegoal of reviewing of this theory and its influence in China. 展开更多
关键词 "i+ 1" INPUT hypothesis FOREIGN language teaching methods
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人工智能赋能人文社会科学研究方法变革 被引量:10
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作者 苏新宁 吕先竞 《西华大学学报(哲学社会科学版)》 2025年第1期1-10,F0002,共11页
以AlphaFold和ChatGPT为代表的人工智能,正在改变整个人类社会,驱动科学研究也驱动人文社会科学研究新范式的形成。“人工智能驱动的人文社会科学研究(AI4SS)”又称人文社科研究第五范式。与分别基于实验、基于理论、基于仿真、基于数... 以AlphaFold和ChatGPT为代表的人工智能,正在改变整个人类社会,驱动科学研究也驱动人文社会科学研究新范式的形成。“人工智能驱动的人文社会科学研究(AI4SS)”又称人文社科研究第五范式。与分别基于实验、基于理论、基于仿真、基于数据驱动的科学研究第一、二、三、四范式不同,人文社科研究第五范式具有AI全学科全过程赋能人文社会科学研究、机器涌现的智能成为人文社会科学研究的组成部分、利用AI概率统计模型解决社会科学研究中的组合爆炸问题、AI为人文社会科学研究构筑多节点的复杂网络、AI虚拟现实促进人文社会科学理论研究与实践结合以及以大模型为特征的科研大平台成为人文社会科学研究的必需等六大特点。AI4SS引发人文社会科学领域的革命,在人文社会科学研究中全面驱动选题与学术史梳理、假设生成及假设论证的方法变革。为加快推进AI赋能人文社会科学研究方法变革,加快面向其研究的开源开放大模型建设是必需的。 展开更多
关键词 人工智能 人文社会科学研究 AI4SS 研究范式 研究方法变革 学术史梳理 假设生成 假设论证 开源基础设施
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富春江水库流域径流变化及其量化归因分析 被引量:3
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作者 司伟 黄思琦 +2 位作者 王培霞 张永康 张健 《河海大学学报(自然科学版)》 北大核心 2025年第3期1-7,共7页
为探明富春江水库流域径流演变的主要驱动因子,基于对富春江水库流域1970—2022年径流深、降水量、潜在蒸散发的趋势性和突变性分析,采用Budyko假设归因法量化降水量、潜在蒸散发、下垫面条件对径流变化的贡献。结果表明:降水量和径流... 为探明富春江水库流域径流演变的主要驱动因子,基于对富春江水库流域1970—2022年径流深、降水量、潜在蒸散发的趋势性和突变性分析,采用Budyko假设归因法量化降水量、潜在蒸散发、下垫面条件对径流变化的贡献。结果表明:降水量和径流深均呈不显著上升趋势,潜在蒸散发呈显著上升趋势;径流深突变年份为2012年;径流深增大的主要原因是降水量的增加、由不透水区域面积增加与森林面积减少导致的下垫面参数改变,其贡献率分别为51.61%和52.55%;径流深减小由潜在蒸散发的增加造成,贡献率为4.16%。 展开更多
关键词 径流变化 Budyko假设归因法 量化归因分析 富春江水库流域
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1956-2022年黄河入海水量演变特征及其归因分析 被引量:1
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作者 朱翰林 何国华 +4 位作者 赵勇 王建华 何凡 李雯晴 王宣宣 《水资源保护》 北大核心 2025年第6期167-175,共9页
为量化人类活动和气候变化对黄河入海水量演变的影响,将经济社会耗水纳入计算过程,利用还原后的天然径流数据,基于Budyko假设的弹性系数法,分析了1956—2022年黄河入海水量的演变特征,识别了断流前(1956—1971年)、断流期(1972—1998年... 为量化人类活动和气候变化对黄河入海水量演变的影响,将经济社会耗水纳入计算过程,利用还原后的天然径流数据,基于Budyko假设的弹性系数法,分析了1956—2022年黄河入海水量的演变特征,识别了断流前(1956—1971年)、断流期(1972—1998年)和恢复期(1999—2022年)不同阶段黄河入海水量变化的驱动因素。结果表明:1956—2022年黄河入海水量呈显著下降趋势,尽管2018—2022年入海水量明显增加,但恢复期的年均入海水量仍低于断流期;经济社会耗水增加是断流期黄河入海水量衰减的主导因素,其贡献率为44.45%;恢复期入海水量进一步减少的主导因素为下垫面变化,其贡献率为100.74%;黄河未来入海水量变化仍存在不确定性,需进一步研究论证入海水量演变态势,保障黄河流域水资源的可持续利用。 展开更多
关键词 黄河入海水量 天然径流 经济社会耗水 Budyko假设 弹性系数法
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基于序贯贝叶斯方法的核素快速检测方法研究
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作者 万琳健 张璇 +5 位作者 张春雷 黄建微 柳加成 张晓乐 李德红 杨智君 《核技术》 北大核心 2025年第1期102-114,共13页
适当的放射性核素快速检测方法对于具有流量大和计数率水平低特征的海关放射性安检等场景是必要的。相较于传统不确定性分析方法,贝叶斯方法和序贯概率比检验可充分利用测量物理量的全部信息而所需的样本量较少,基于此提出了一种新型序... 适当的放射性核素快速检测方法对于具有流量大和计数率水平低特征的海关放射性安检等场景是必要的。相较于传统不确定性分析方法,贝叶斯方法和序贯概率比检验可充分利用测量物理量的全部信息而所需的样本量较少,基于此提出了一种新型序贯贝叶斯核素快速检测方法,分别在低辐射本底环境和自然辐射本底环境,使用一套LaBr3(Ce)探测系统和一组标准点源对该方法的可行性、检测性能和普适性开展了实验研究,并探究了方法的关键参数中第一类错误概率α、第二类错误概率β和时间间隔下限τmin对检测性能的影响。在本底计数率分别为59.3 s^(-1)和165.9 s^(-1)的两类本底环境中,α和β分别不超过0.1和0.01的条件下,实验结果显示:在无源情况下,该方法对本底辐射的平均检出时间分别为24.08 s和10.54 s,平均检出样本量分别为1427和1742,且发生误报后均可快速自适应消除并做出有效判决;在有源情况下,实验测量检测灵敏度下限分别约为8.2%和6.1%,对应的平均检出时间分别为8.59 s和6.61 s,实验测量漏报率均为0,平均检出时间只与全谱净计数率有关,平均检出样本量只与放射源信号的计数率信噪比有关,检测灵敏度下限可理论计算且与实验结果相吻合;参数τ_(min)的减小会增大检测灵敏度下限和减小检出时间,参数α和β可决定实验测量误报率和漏报率。研究表明本方法非常适用于低水平放射性核素的快速检测。 展开更多
关键词 序贯贝叶斯方法 放射性核素快速检测 二元假设 检测灵敏度下限
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基于系数平均的混合地理加权回归模型的估计及其系数类型辨识
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作者 梅长林 成佳媛 续秋霞 《工程数学学报》 北大核心 2025年第2期199-219,共21页
混合地理加权回归模型假定部分回归系数是常数,其余回归系数随空间位置变化,是综合探索自变量对因变量影响的空间变化特征的有力工具。以回归系数的局部线性地理加权估计为基础,提出了基于系数平均的混合地理加权回归模型的估计方法及... 混合地理加权回归模型假定部分回归系数是常数,其余回归系数随空间位置变化,是综合探索自变量对因变量影响的空间变化特征的有力工具。以回归系数的局部线性地理加权估计为基础,提出了基于系数平均的混合地理加权回归模型的估计方法及其常值系数的Bootstrap检验方法。进一步将估计和检验方法推广到多类型系数混合地理加权回归模型的估计及其系数类型的辨识。模拟实验表明所提出的估计方法与现有的二步估计相比对空间变系数具有更高的估计精度,有关检验方法对辨识特殊类型系数具有满意的检验功效。最后,通过实例分析说明了所提估计和检验方法的具体应用。 展开更多
关键词 地理加权回归 混合地理加权回归模型 假设检验 BOOTSTRAP方法
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变化环境下大沽河流域汛期径流变化特性研究
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作者 杨富香 拾兵 李松 《水生态学杂志》 北大核心 2025年第5期90-100,共11页
基于模型分析水库调蓄对流域径流的影响,为大沽河流域水资源管理及未来规划提供理论参考。依据南村水文站1962—2022年逐日径流数据、气象数据等资料,利用Pettitt突变检验法、累积距平法及B-G分割算法检验汛期径流的突变点,采用IHA-RVA... 基于模型分析水库调蓄对流域径流的影响,为大沽河流域水资源管理及未来规划提供理论参考。依据南村水文站1962—2022年逐日径流数据、气象数据等资料,利用Pettitt突变检验法、累积距平法及B-G分割算法检验汛期径流的突变点,采用IHA-RVA法分析大沽河流域突变前后汛期径流的水文改变程度;基于Budyko假设的水热耦合平衡方程分析量化气候变化和人类活动对汛期径流改变的贡献程度;借助SWAT模型对比有无水库两种情形下净流量,分析水库调蓄对汛期径流的影响。结果表明:(1)大沽河流域汛期径流的突变点约在1976年左右,发生了中度改变,整体水文改变度为61.17%;(2)大沽河汛期径流对降雨最为敏感,其次是潜在蒸散发、下垫面参数;(3)人类活动(下垫面条件变化)对汛期径流的减少起主导作用,贡献率超过70%,气候变化的贡献率不到30%;(4)水库调蓄之后,汛期径流量显著减少,尤其是7月和8月,分别约减少23.33%、30.50%。 展开更多
关键词 径流变化 IHA-RVA法 Budyko假设 归因分析 SWAT模型 大沽河流域
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中医调治体外受精-胚胎移植临证经验总结
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作者 邢艺璇 唐诗 +4 位作者 刘未艾 游卉 刘文娥 莫蕙 尤昭玲 《湖南中医药大学学报》 2025年第9期1602-1606,共5页
体外受精-胚胎移植(IVF-ET)助孕技术现今已广泛运用于不孕症的治疗。尤昭玲教授在“生殖链-终端效应”临证假说和“生殖双环网络”理论基础上,将中药内服、药膳制剂、耳穴压豆等不同中医治法融入IVF-ET的降调、促排、移植、妊娠4个周期... 体外受精-胚胎移植(IVF-ET)助孕技术现今已广泛运用于不孕症的治疗。尤昭玲教授在“生殖链-终端效应”临证假说和“生殖双环网络”理论基础上,将中药内服、药膳制剂、耳穴压豆等不同中医治法融入IVF-ET的降调、促排、移植、妊娠4个周期,并分为进周前和进周后二段式调治,总结为“二段四期三法”。本文详细阐述尤昭玲教授“二段四期三法”中医调治IVF-ET全过程的诊疗内涵,并通过医案举隅,旨在通过精准选择治疗顺序以及治疗方法,以期提高IVF-ET的助孕妊娠率。 展开更多
关键词 体外受精-胚胎移植 二段四期三法 全过程管理 “生殖链-终端效应”临证假说 “生殖双环网络”理论 尤昭玲
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