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Reliability Function of Non-independent Random Variables Subject to Two-Dimensional Standard Normal Distribution
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作者 Yangjing Chong Xinhui Zhou +2 位作者 Yutong Zhu Hailing Lan Yunfei Guo 《信息工程期刊(中英文版)》 2016年第4期93-98,共6页
关键词 可靠性 分发 标准 二维 非独立 随机 案例分析
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An improved model of partition curve based on accumulation normal distribution function 被引量:2
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作者 Sun Wei Chen Jianzhong +1 位作者 Shen Lijuan Li Yonggai 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期375-380,共6页
Extensive studies based on partition curve of gravity separation have been investigated. All created models are merely used to simulate density distribution at the same size fraction. However, they cannot be used to p... Extensive studies based on partition curve of gravity separation have been investigated. All created models are merely used to simulate density distribution at the same size fraction. However, they cannot be used to predictive distribution of materials depending on compound feature of density and size. According to this situation, an improved model of partition curve based on accumulation normal distribution, which was distinguished from conventional model of accumulation normal distribution for partition curve, was proposed in this paper. It could simulate density distribution at different size fractions by using the density-size compound index and conflating the partition curves at different size fractions as one partition curve. The feasibility of three compound indexes, including mass index, settlement index and transformation index, were investigated. Specific forms of the improved model were also proposed. It is found that transformation index leads to the best fitting results, while the fitting error is only 1.75 according to the fitting partition curve. 展开更多
关键词 Coal preparation Mathematical model Partition curve accumulation normal distribution model
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Distribution of driving trajectory of passenger car in highway horizontal curves
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作者 任园园 李显生 +1 位作者 郭伟伟 王吉亮 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期222-228,共7页
In this paper the track behavior of passenger car was studied. The vehicle driving trajectory and driving direction were defined, and a classification of the type of vehicle trajectories along the curves was developed... In this paper the track behavior of passenger car was studied. The vehicle driving trajectory and driving direction were defined, and a classification of the type of vehicle trajectories along the curves was developed. The statistical parameters of vehicle trajectory samples in free flow and their frequency curves and cumulative frequency curves were achieved, K-S test and chi-square test were used to test normal distribution and gamma distribution for collected sample data, and the probabili- ty density functions were given. At last, dispersion degree between vehicle trajectory random varia- ble and the characteristic value of cumulative frequency curve in each key cross section in curves was analyzied. The proposed conclusion can provide theoretical support for the reasonable optimization of widen curve, design of alignment and the management of counter flow conflicts. 展开更多
关键词 traffic safety vehicle trajectory transverse deviation gamma distribution normal dis-tribution horizontal curve
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三维power-normal分布的性质及参数估计问题的研究 被引量:1
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作者 孙丽红 李树有 《辽宁工业大学学报(自然科学版)》 2017年第3期190-195,共6页
应用了Clayton连接函数的性质给出了三维power-normal分布的分布函数及概率密度函数,并详细研究了三维power-normal分布的基本性质,同时,根据所构造出的三维power-normal分布模型,对其中的参数进行了最大似然估计的讨论。并给出了参数... 应用了Clayton连接函数的性质给出了三维power-normal分布的分布函数及概率密度函数,并详细研究了三维power-normal分布的基本性质,同时,根据所构造出的三维power-normal分布模型,对其中的参数进行了最大似然估计的讨论。并给出了参数的最大似然估计的算法。结合费永法在文献中的1964年到1973年10年间长江大通站、淮河中渡站及黄河花园口站的天然年流经量数据作为样本数据,利用MATLAB程序计算了参数的最大似然估计。 展开更多
关键词 power-normal分布 极大似然估计 Clayton连接函数 三维分布 MaTLaB
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基于IDA的群体典型框架结构的震害预测研究 被引量:5
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作者 李葱葱 马东辉 王志涛 《中国安全科学学报》 CAS CSCD 北大核心 2013年第4期127-132,共6页
为了更好地服务于城市抗震防灾规划,研究典型钢筋混凝土(RC)框架结构建筑群体震害矩阵,形成初步适用于群体震害预测的方法。建立设防烈度分别为6,7,8度的3层典型框架结构和设防烈度为7度下的3,6,9层的典型框架结构模型,然后在动力增量... 为了更好地服务于城市抗震防灾规划,研究典型钢筋混凝土(RC)框架结构建筑群体震害矩阵,形成初步适用于群体震害预测的方法。建立设防烈度分别为6,7,8度的3层典型框架结构和设防烈度为7度下的3,6,9层的典型框架结构模型,然后在动力增量时程分析(IDA)方法的基础上,分析各框架结构在不同地震作用下的破坏规律。最终得到各框架结构在地震作用下的易损性曲线和震害矩阵。结果表明,各破坏状态下的易损性曲线符合对数正态函数分布;典型框架结构随着抗震设防烈度的提高,抗地震破坏能力增加;随着层数的增加,抗地震破坏能力减弱。 展开更多
关键词 动力增量时程分析(IDa) 抗震设防烈度 易损性曲线 震害矩阵 典型框架结构 对数正态分布 钢筋混凝土(RC)
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ROC曲线中Az值的物理意义及数学表达 被引量:3
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作者 王昌元 谢晋东 李月卿 《泰山医学院学报》 CAS 2003年第2期102-105,共4页
目的 探索ROC曲线下面积Az值与ND轴坐标系下截距a的关系。方法 假设信号 (signal,S)与噪声(noise,N)服从同一方差的正态分布 ,使用积分中的换元法求出Az值与截距的关系式 ,并编程由a计算出Az值。结果 Az值介于 0 5到 1之间 ,随a的... 目的 探索ROC曲线下面积Az值与ND轴坐标系下截距a的关系。方法 假设信号 (signal,S)与噪声(noise,N)服从同一方差的正态分布 ,使用积分中的换元法求出Az值与截距的关系式 ,并编程由a计算出Az值。结果 Az值介于 0 5到 1之间 ,随a的增大而增加。结论 Az值与a之间有内在的关系 ,均可反映诊断水平的高低。 展开更多
关键词 ROC曲线 信号 噪声 正态分布 ROC曲线下的面积(az) 截距
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Hybrid reliability model for fatigue reliability analysis of steel bridges 被引量:1
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作者 曹珊珊 雷俊卿 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期449-460,共12页
A kind of hybrid reliability model is presented to solve the fatigue reliability problems of steel bridges. The cumulative damage model is one kind of the models used in fatigue reliability analysis. The parameter cha... A kind of hybrid reliability model is presented to solve the fatigue reliability problems of steel bridges. The cumulative damage model is one kind of the models used in fatigue reliability analysis. The parameter characteristics of the model can be described as probabilistic and interval. The two-stage hybrid reliability model is given with a theoretical foundation and a solving algorithm to solve the hybrid reliability problems. The theoretical foundation is established by the consistency relationships of interval reliability model and probability reliability model with normally distributed variables in theory. The solving process is combined with the definition of interval reliability index and the probabilistic algorithm. With the consideration of the parameter characteristics of the S-N curve, the cumulative damage model with hybrid variables is given based on the standards from different countries. Lastly, a case of steel structure in the Neville Island Bridge is analyzed to verify the applicability of the hybrid reliability model in fatigue reliability analysis based on the AASHTO. 展开更多
关键词 hybrid reliability model (HRM) consistency relationships linear and bilinear S-N curve fatigue reliability normal distribution
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Statistical Classification Using the Maximum Function 被引量:1
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作者 T. Pham-Gia Nguyen D. Nhat Nguyen V. Phong 《Open Journal of Statistics》 2015年第7期665-679,共15页
The maximum of k numerical functions defined on , , by , ??is used here in Statistical classification. Previously, it has been used in Statistical Discrimination [1] and in Clustering [2]. We present first some theore... The maximum of k numerical functions defined on , , by , ??is used here in Statistical classification. Previously, it has been used in Statistical Discrimination [1] and in Clustering [2]. We present first some theoretical results on this function, and then its application in classification using a computer program we have developed. This approach leads to clear decisions, even in cases where the extension to several classes of Fisher’s linear discriminant function fails to be effective. 展开更多
关键词 MaXIMUM DISCRIMINaNT Function Pattern Classification normal distribution BaYES Error L1-Norm Linear QUaDRaTIC Space curveS
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用AUTOLISP语言编程绘制三维图
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作者 程学忠 《物探化探计算技术》 CAS CSCD 2001年第1期87-89,共3页
作者在文中介绍了在计算机辅助设计软件 AUTOCAD中使用 AUTOLISP语言的编程原理。用一个典型的实例 ,说明程序的设计过程 ,并附有程序清单及注解。可作为教学示例使用 ,很有实用价值。
关键词 S表达式 正态分布 钟形线 aUTOLISP语言 三维图 绘制 CaD
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On Efficient Monitoring of Process Dispersion using Interquartile Range
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作者 Shabbir Ahmad Zhengyan Lin +1 位作者 Saddam Akber Abbasi Muhammad Riaz 《Open Journal of Applied Sciences》 2012年第4期39-43,共5页
The presence of dispersion/variability in any process is understood and its careful monitoring may furnish the performance of any process. The interquartile range (IQR) is one of the dispersion measures based on lower... The presence of dispersion/variability in any process is understood and its careful monitoring may furnish the performance of any process. The interquartile range (IQR) is one of the dispersion measures based on lower and upper quartiles. For efficient monitoring of process dispersion, we have proposed auxiliary information based Shewhart-type IQR control charts (namely IQRr and IQRp charts) based on ratio and product estimators of lower and upper quartiles under bivariate normally distributed process. We have developed the control structures of proposed charts and compared their performances with the usual IQR chart in terms of detection ability of shift in process dispersion. For the said purpose power curves are constructed to demonstrate the performance of the three IQR charts under discussion in this article. We have also provided an illustrative example to justify theory and finally closed with concluding remarks. 展开更多
关键词 aUXILIaRY Information BIVaRIaTE normal distribution Control Carts Interquartile RaNGE LOWER and UPPER Quartiles Power curves.
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The Compound Indexing of Human Self-Similar Behavioural Patterns
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作者 Petr Kloucek Pavel Zakharov Armin von Gunten 《Applied Mathematics》 2016年第17期2212-2228,共18页
Applications of a constitutive framework providing compound complexity analysis and indexing of coarse-grained self-similar time series representing behavioural data are presented. A notion of behavioural entropy and ... Applications of a constitutive framework providing compound complexity analysis and indexing of coarse-grained self-similar time series representing behavioural data are presented. A notion of behavioural entropy and hysteresis is introduced as two different forms of compound measures. These measures provide clinically applicable complexity analysis of behavioural patterns yielding scalar characterisation of time-varying behaviours registered over an extended period of time. The behavioural data are obtained using body attached sensors providing non-invasive readings of heart rate, skin blood perfusion, blood oxygenation, skin temperature, movement and steps frequency. The results using compound measures of behavioural patterns of fifteen healthy individuals are presented. The application of the compound measures is shown to correlate with complexity analysis. The correlation is demonstrated using two healthy subjects compared against a control group. This indicates a possibility to use these measures in place of fractional dimensions to provide a finer characterisation of behavioural patterns observed using sensory data acquired over a long period of time. 展开更多
关键词 Behavioural Complexity Physiological and Behavioural Surrogate Data Behavioural Entropy Behavioural Hysteresis Seld-Similar normally Distributed Precesses Non-Integer Hausdorff-Besicovitch Dimension Hurst Exponent
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Study on the regional deviation of the mac-roscopic epicenters from relevant epicenters by rapid determination in Chinese mainland
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作者 刘吉夫 王晓青 +1 位作者 陈颙 黄辅琼 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第1期39-43,共5页
The primary results have been obtained by the analyses on the deviation of macroscopic epicenters from relevant microscopic epicenters determined rapidly after the 139 earthquake events occunrred during 1989-2004. Fur... The primary results have been obtained by the analyses on the deviation of macroscopic epicenters from relevant microscopic epicenters determined rapidly after the 139 earthquake events occunrred during 1989-2004. Further study has proved the normal distributions exist in both the east and west parts of Chinese mainland partitioned along meridian 105°E. The empirical two-dimensional normal distribution functions for the deviations are presented in the paper. The results are of significance in reducing uncertainty of losses assessment immediately after a destroyed earthquake. 展开更多
关键词 Chinese mainland macroscopic epicenter microscopic epicenter regional two-dimensional normal distribution uncertainty
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二维曲线型随机变量函数概率分布的计算
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作者 涂振坤 宁荣健 《高师理科学刊》 2024年第11期77-80,共4页
利用转换法给出二维曲线型随机变量函数概率分布的求解方法,指出在特殊情形下其与一维连续型随机变量函数概率分布的关系,并举例说明了求解方法的有效性.所给结果为二维曲线型随机变量的相关研究提供了新思路,具有一定的教学参考价值.
关键词 二维连续型随机变量 二维曲线型随机变量 概率分布 密度函数 曲线积分
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基于二维正态分布的无人机激光雷达点云匹配研究 被引量:1
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作者 任娜 张玉 +1 位作者 王洪江 张楠 《激光杂志》 CAS 北大核心 2024年第4期265-270,共6页
无人机激光雷达点云特征多,一次匹配花时间长,难以进行二次匹配,因此研究基于二维正态分布的无人机激光雷达点云匹配方法。采集无人机激光雷达点云图像,通过旋转平移方法、双边滤波方法对图像预处理,利用二维正态分布算法和动态时间规... 无人机激光雷达点云特征多,一次匹配花时间长,难以进行二次匹配,因此研究基于二维正态分布的无人机激光雷达点云匹配方法。采集无人机激光雷达点云图像,通过旋转平移方法、双边滤波方法对图像预处理,利用二维正态分布算法和动态时间规整算法完成点云特征提取,使用初始变换矩阵估计算法对点云进行粗匹配,再使用近点迭代算法进行点云快速精匹配,通过两次匹配实现无人机激光雷达点云快速匹配。实验结果表明,所提方法的无人机激光雷达点云图像去噪效果好,点云匹配时间短,匹配偏差仅在0.04 m-0.15 m之间,匹配精度达到了相关预期。 展开更多
关键词 二维正态分布 无人机激光雷达 点云匹配 旋转平移方法 点云特征 粗匹配 精匹配
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基于高斯混合模型及EM算法的建筑工程数据预警治理方法 被引量:1
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作者 张静雯 耿天宝 《科学技术创新》 2024年第8期192-195,共4页
结合初期雨水调蓄大直径顶管工程的实际设计及施工经验,对软弱地层条件下长距离大直径平行双管曲线顶管在设计及施工过程中存在的重点难点问题进行总结,并对顶管过程中的顶力及管周摩阻力做了深入分析研究,有针对性地提出了相应的解决方... 结合初期雨水调蓄大直径顶管工程的实际设计及施工经验,对软弱地层条件下长距离大直径平行双管曲线顶管在设计及施工过程中存在的重点难点问题进行总结,并对顶管过程中的顶力及管周摩阻力做了深入分析研究,有针对性地提出了相应的解决方案,使该顶管工程顺利贯通。建筑工程行业在现代社会中发挥着重要的经济和社会作用,然而,它也伴随着诸多风险和不确定性。为了有效地管理和预测这些风险,本文提出了一种基于高斯混合模型(GMM)和期望最大化(EM)算法的数据预警治理方法。该方法旨在通过对建筑工程数据的建模和分析,提前识别潜在的问题和风险,从而改善工程项目的管理和决策。 展开更多
关键词 GMM高斯混合模型 EM算法 数据预警治理 正态分布曲线 后验概率
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Generalized T3-plot for testing high-dimensional normality 被引量:1
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作者 Mingyao AI Jiajuan LIANG Man-Lai TANG 《Frontiers of Mathematics in China》 SCIE CSCD 2016年第6期1363-1363,1364-1378,共16页
A new dimension-reduction graphical method for testing high- dimensional normality is developed by using the theory of spherical distributions and the idea of principal component analysis. The dimension reduction is r... A new dimension-reduction graphical method for testing high- dimensional normality is developed by using the theory of spherical distributions and the idea of principal component analysis. The dimension reduction is realized by projecting high-dimensional data onto some selected eigenvector directions. The asymptotic statistical independence of the plotting functions on the selected eigenvector directions provides the principle for the new plot. A departure from multivariate normality of the raw data could be captured by at least one plot on the selected eigenvector direction. Acceptance regions associated with the plots are provided to enhance interpretability of the plots. Monte Carlo studies and an illustrative example show that the proposed graphical method has competitive power performance and improves the existing graphical method significantly in testing high-dimensional normality. 展开更多
关键词 Dimension reduction graphical method high-dimensional data multivariate normality spherical distribution
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正态分布规律下尺寸链设计分析
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作者 邓敬亮 刘才丽 劳贤豪 《航空发动机》 北大核心 2024年第1期164-169,共6页
为了提供尺寸链评判的量化依据、优化尺寸链关联尺寸的设计、降低零件加工成本,提出了一种新的基于正态分布规律的概率法尺寸链设计方法。通过概率法分析可知尺寸在设计公差范围内的分布规律服从正态分布,推导出在尺寸链中封闭环也服从... 为了提供尺寸链评判的量化依据、优化尺寸链关联尺寸的设计、降低零件加工成本,提出了一种新的基于正态分布规律的概率法尺寸链设计方法。通过概率法分析可知尺寸在设计公差范围内的分布规律服从正态分布,推导出在尺寸链中封闭环也服从正态分布,从而得出封闭环在设计要求区间内的概率值,进而评判机械装配中的间隙、干涉等是否具有合理性。结果表明:该尺寸链设计法可根据封闭环在设计要求区间的实际情况以概率值进行量化,从而使尺寸链设计的评判更加具体化;封闭环的区间概率值与尺寸链中的组成环可进行关联,因而对组成环的各零件尺寸进行调整优化,以提高封闭环的区间概率;对封闭环区间概率过低的情况,给出了在尺寸链中增加调整垫的设计方法和原则。 展开更多
关键词 尺寸链 概率法 正态分布 机械设计 封闭环 组成环 调整垫 航空发动机
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正态云模型相似度计算方法 被引量:95
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作者 李海林 郭崇慧 邱望仁 《电子学报》 EI CAS CSCD 北大核心 2011年第11期2561-2567,共7页
本文提出了两种正态云模型相似度计算方法,分别通过正态云模型的期望曲线和最大边界曲线来描述正态云模型的总体特征,实现以期望曲线相似程度或最大边界曲线的相似程度对正态云模型相似度的定量表示.它们在一定程度上克服了传统基于特... 本文提出了两种正态云模型相似度计算方法,分别通过正态云模型的期望曲线和最大边界曲线来描述正态云模型的总体特征,实现以期望曲线相似程度或最大边界曲线的相似程度对正态云模型相似度的定量表示.它们在一定程度上克服了传统基于特征向量和随机选取云滴的相似度计算带来云模型期望数字特征过于显著、时间复杂度过高和结果不稳定等方面的不足.实验结果表明,本文算法能够更为客观地对正态云模型进行相似度计算,在协同过滤推荐以及时间序列分类中得到了应用并提高了算法的效率. 展开更多
关键词 云模型 相似性度量 正态分布 期望曲线 最大边界曲线
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随机抽样在粗糙表面接触力学行为分析中的应用 被引量:10
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作者 许志倩 闫相祯 +2 位作者 杨秀娟 秦志坚 丁文超 《西安交通大学学报》 EI CAS CSCD 北大核心 2012年第5期102-108,113,共8页
为研究表面粗糙度对接触表面力学行为的影响规律,结合表面粗糙度的加工参数和随机抽样方法,对服从正态分布和预设粗糙度的表面轮廓曲线进行了模拟.根据统计得到的模拟轮廓曲线几何形态的共性特征,建立了基于圆锥与平面接触的三维粗糙表... 为研究表面粗糙度对接触表面力学行为的影响规律,结合表面粗糙度的加工参数和随机抽样方法,对服从正态分布和预设粗糙度的表面轮廓曲线进行了模拟.根据统计得到的模拟轮廓曲线几何形态的共性特征,建立了基于圆锥与平面接触的三维粗糙表面接触力学模型,推导出平面几何压力与粗糙表面微凸体变形间的定量关系.分析结果表明:服从正态分布的轮廓高度曲线中的峰角顶点数目约为样本容量的1/3;圆锥压入平面时平均压力/材料纯剪应力的比值与其半角呈二次方关系;表面粗糙度越大,轮廓曲线的起伏越大,两接触面相互嵌合越容易;表面粗糙度越大,材料屈服强度对接触微凸体变形的影响也越明显. 展开更多
关键词 接触 粗糙表面 轮廓曲线 正态分布
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基于正态分布时间函数地表动态沉陷预测研究 被引量:24
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作者 李春意 高永格 崔希民 《岩土力学》 EI CAS CSCD 北大核心 2016年第S1期108-116,共9页
为了研究地表动态沉陷规律,基于正态分布时间函数,结合地表沉陷预测公式,构建了能够进行任意点任意时刻地表动态沉陷预测的函数模型,分析曲线形态系数对时间函数和计算误差的影响,讨论正态分布时间函数的时空完备性,建立了基于时间函数... 为了研究地表动态沉陷规律,基于正态分布时间函数,结合地表沉陷预测公式,构建了能够进行任意点任意时刻地表动态沉陷预测的函数模型,分析曲线形态系数对时间函数和计算误差的影响,讨论正态分布时间函数的时空完备性,建立了基于时间函数的地表动态下沉计算公式。以辛置煤矿五采区开采为例,利用空间曲面拟合方法求取了地表动态沉陷预测参数,并对特征点的下沉趋势进行了预测。结果表明,地表沉陷预测时曲线形态系数δ>2为其合理取值,理论预测相对中误差不会超过±4.55%,且随着δ的增大,预测误差逐渐减小;正态分布时间函数在地表下沉、下沉速度以及加速度方面均体现了地表沉陷时空分布的完备性。基于叠加原理的空间曲面拟合求参方法能够进行预测参数的自动求取,地表特征点下沉趋势预测最大中误差为±64 mm,相对中误差为±5.7%,理论值与实测值相吻合,基于正态分布时间函数的预测模型能够体现地表动态下沉的时空分布特征。 展开更多
关键词 时间函数 正态分布 动态下沉 预测模型 曲面拟合
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