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Quantitative Analysis Model and Application of the Hydrocarbon Distribution Threshold 被引量:6
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作者 JIANG Fujie PANG Xiongqi GUO Jigang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第1期232-242,共11页
Hydrocarbon source rock obviously controls the formation and distribution of hydrocarbon reservoirs. Based on the geological concept of "source control theory", the concept of a hydrocarbon distribution threshold wa... Hydrocarbon source rock obviously controls the formation and distribution of hydrocarbon reservoirs. Based on the geological concept of "source control theory", the concept of a hydrocarbon distribution threshold was put forward. This means the maximum range for hydrocarbon controlled by the source rock conditions to migrate in the hydrocarbon basins. Three quantitative analysis models are proposed on this basis, namely the hydrocarbon accumulation probability, maximum hydrocarbon scale threshold and reserve distribution probability, which respectively refer to the probability of forming a hydrocarbon reservoir, the possible maximum scale of the hydrocarbon reservoir and the percentage of reserve distribution in a certain area within the hydrocarbon distribution threshold. Statistical analysis on 539 hydrocarbon reservoirs discovered in 28 hydrocarbon source kitchens from seven sedimentary basins and sags of eastern China shows the maximum reservoir scale possibly formed in the hydrocarbon basin, hydrocarbon accumulation probability and oil and gas reserve distribution probability are all controlled by the characteristics of the hydrocarbon source rock. Generally, as the distances from the hydrocarbon source rock center and hydrocarbon discharge boundary get longer and the hydrocarbon discharge intensity of hydrocarbon source rock center gets smaller, there will be lower probability of hydrocarbon accumulation. Corresponding quantitative models are established based on single factor statistics and multivariate analysis. Practical application in the Jiyang Depression shows that the prediction from the quantitative analysis model for the hydrocarbon distribution threshold agree well with the actual exploration results, indicating that the quantitative analysis model is likely to be a feasible tool. 展开更多
关键词 source control theory scale threshold distribution threshold Jiyang Depression hydrocarbon discharge threshold probability
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Estimating Design Loads with Environmental Contour Approach Using Copulas for an Offshore Jacket Platform 被引量:2
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作者 ZHAO Yuliang LIU Dahui DONG Sheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第5期1029-1041,共13页
Jacket-type offshore platforms are widely used for oil, gas field, and energy development in shallow water. The design of a jacket structure is highly dependent on target environmental variables. This study focuses on... Jacket-type offshore platforms are widely used for oil, gas field, and energy development in shallow water. The design of a jacket structure is highly dependent on target environmental variables. This study focuses on a strategy to estimate design loads for offshore jacket structures based on an environmental contour approach. In addition to the popular conditional distribution model, various classes of bivariate copulas are adopted to construct joint distributions of environmental variables. Analytical formulations of environmental contours based on various models are presented and discussed in this study. The design loads are examined by dynamic response analysis of jacket platform. Results suggest that the conditional model is not recommended for use in estimating design loads in sampling locations due to poor fitting results. Independent copula produces conservative design loads and the extreme response obtained using the conditional model are smaller than those determined by copulas. The suitability of a model for contour construction varies with the origin of wave data. This study provides a reference for the design load estimation of jacket structures and offers an alternative procedure to determine the design criteria for offshore structures. 展开更多
关键词 design loads jacket platform joint probability distribution conditional model copula theory environmental contour method
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An Estimation Method for Kill Probability Based on Random Residence Time Series
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作者 刘超 王军 郭治 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第4期229-234,共6页
Relations between statistical residence time series and effective shooting are analyzed in accordance with the properties of the random residence time of maneuver targets crossing shot area in a given time. An estimat... Relations between statistical residence time series and effective shooting are analyzed in accordance with the properties of the random residence time of maneuver targets crossing shot area in a given time. An estimation method for kill probability is proposed, which solves the probability of number of residence times satisfied effective shooting in given time. Some expressions and their approximate formulae of kill probability are derived, under known the distribution of residence time series. Theoretical analysis and simulation results show that this method is suitable for evaluating the hit ability of fire system for maneuver targets in random shooting. 展开更多
关键词 probability theory kill probability shooting area residence time Poisson process Gamma distribution
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Slant Range Distribution Characteristics of Submarine Launch Mobile Mine
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作者 冷相文 张旭 +1 位作者 赵晓哲 刘晓华 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第4期258-261,共4页
With the bias between the predetermined planting location and the fact mine position,slant range of SLMM(submarine launch mobile mine)appears randomly scattered.The normal distribution model of slant range was propose... With the bias between the predetermined planting location and the fact mine position,slant range of SLMM(submarine launch mobile mine)appears randomly scattered.The normal distribution model of slant range was proposed by the distribution theory of multivariate random variables,and the simplified model based on key parameters was present,and the laws of slant range distribution parameters such as mean and variance were given,which were affected by key parameters.The conclusions ensure that slant range of SLMM can be controlled when laying mines and provide the basis for tactical decision-making. 展开更多
关键词 probability theory SLMM slant range distribution model mine-laying decision
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Numerical Procedures for Calculating the Probabilities of Recurrent Runs
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作者 M. P. Silverman 《Open Journal of Statistics》 2014年第2期144-153,共10页
Run count statistics serve a central role in tests of non-randomness of stochastic processes of interest to a wide range of disciplines within the physical sciences, social sciences, business and finance, and other en... Run count statistics serve a central role in tests of non-randomness of stochastic processes of interest to a wide range of disciplines within the physical sciences, social sciences, business and finance, and other endeavors involving intrinsic uncertainty. To carry out such tests, it is often necessary to calculate two kinds of run count probabilities: 1) the probability that a certain number of trials results in a specified multiple occurrence of an event, or 2) the probability that a specified number of occurrences of an event take place within a fixed number of trials. The use of appropriate generating functions provides a systematic procedure for obtaining the distribution functions of these probabilities. This paper examines relationships among the generating functions applicable to recurrent runs and discusses methods, employing symbolic mathematical software, for implementing numerical extraction of probabilities. In addition, the asymptotic form of the cumulative distribution function is derived, which allows accurate runs statistics to be obtained for sequences of trials so large that computation times for extraction of this information from the generating functions could be impractically long. 展开更多
关键词 RECURRENT EVENTS theory of RUNS Time Series Analysis GENERATING Functions probability distributionS
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考虑温度和时间双重影响的混凝土蠕变模型构建
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作者 向学敏 文祝 +2 位作者 郭莉梅 徐辉 王楠 《金属矿山》 CAS 北大核心 2024年第4期87-94,共8页
为了研究温度对混凝土结构蠕变特性的影响,开展不同温度作用下混凝土三轴蠕变试验,分析了不同温度作用下混凝土结构的轴向蠕变特性。在温度作用下,混凝土的内部损伤与非均匀程度参数有关,建立非均匀程度参数与温度之间的关系;假定混凝... 为了研究温度对混凝土结构蠕变特性的影响,开展不同温度作用下混凝土三轴蠕变试验,分析了不同温度作用下混凝土结构的轴向蠕变特性。在温度作用下,混凝土的内部损伤与非均匀程度参数有关,建立非均匀程度参数与温度之间的关系;假定混凝土蠕变模型是关于温度和时间的函数,结合上述损伤变量和微元体强度分布概率模型,建立了考虑温度和时间双重影响的混凝土蠕变模型。基于最小二乘法和试验数据对模型的准确性进行验证,并采用西原模型对其优越性作进一步验证。结果表明:不同温度作用下蠕变损伤模型与试验数据的吻合度都较好,且相关性系数在0.95以上,说明了所建立模型的正确性;同时,该模型与试验数据的吻合度要优于西原模型,并且在描述加速蠕变方面具有一定的优越性。该理论模型为地下工程中混凝土支护结构的长期变形预测研究提供理论依据。 展开更多
关键词 温度 三轴蠕变 损伤理论 强度分布概率 双重影响
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部分信息下相邻2-out-of-n:F系统的可靠性分析
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作者 宋月 刘三阳 冯海林 《工程数学学报》 CSCD 北大核心 2008年第1期103-108,共6页
对相邻2-out-of-n系统可靠性的研究大都假定部件的失效时间分布是已知的,即部件的可靠度是已知的,然而该假设在许多情况下是不合理的(例如软件系统,人机系统)。本文针对部件的失效时间分布未知,仅仅具有关于部件可靠度的部分信息情况,... 对相邻2-out-of-n系统可靠性的研究大都假定部件的失效时间分布是已知的,即部件的可靠度是已知的,然而该假设在许多情况下是不合理的(例如软件系统,人机系统)。本文针对部件的失效时间分布未知,仅仅具有关于部件可靠度的部分信息情况,也就是我们仅仅知道部件的寿命在某些重叠区间的可靠度,利用不精确概率理论分析了该系统,获得了相邻2-out-of-n:F环形与线形系统可靠度上下界的精确公式。最后用例子说明了本文的方法,并指出了在该方向上需要进一步研究解决的问题。 展开更多
关键词 系统可靠性 不精确概率 概率分布 失效时间分布
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肇庆市中心城区暴雨强度公式研究及应用
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作者 陈荣泉 张聪慧 《广东气象》 2024年第2期6-10,共5页
采用年最大值法挑选肇庆市中心城区降水样本,并尝试用皮尔逊Ⅲ型、耿贝尔型、指数分布型3种概率分布函数进行拟合试验,结果表明:皮尔逊Ⅲ型和耿贝尔型通过KS检验;耿贝尔型暴雨强度的精度误差较皮尔逊Ⅲ型为优,最终获得耿贝尔型暴雨强度... 采用年最大值法挑选肇庆市中心城区降水样本,并尝试用皮尔逊Ⅲ型、耿贝尔型、指数分布型3种概率分布函数进行拟合试验,结果表明:皮尔逊Ⅲ型和耿贝尔型通过KS检验;耿贝尔型暴雨强度的精度误差较皮尔逊Ⅲ型为优,最终获得耿贝尔型暴雨强度公式。根据公式计算单一重现期暴雨强度发现,1h降水量达50mm的重现期为2年以内,即每年都会发生;24h降水量达暴雨量级的重现期为2年以内,即每年都会发生;特大暴雨量级的降水的重现期为50年以上。在面对超百年一遇的极端降雨时,需要完善应急管理措施;在预测有强降雨过程来临时,及时做好城市排水管道、调蓄池、行泄通道的调度。 展开更多
关键词 气候学 暴雨强度 概率分布曲线 重现期 肇庆市
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考虑需求侧灵活性资源配置的配电网分布鲁棒优化规划方法研究
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作者 艾欣 王昊洋 +1 位作者 潘玺安 李雪晴 《太阳能学报》 EI CAS CSCD 北大核心 2024年第7期267-277,共11页
考虑需求侧灵活性资源(简称“资源”)配置,开展网-荷-储联合规划是提升配电网灵活性以适应新能源出力波动的关键途径。为此提出一种灵活性缺失场景筛选与不确定性分析方法改进相结合的配电网规划研究模型:首先,立足资源视角进行配电网... 考虑需求侧灵活性资源(简称“资源”)配置,开展网-荷-储联合规划是提升配电网灵活性以适应新能源出力波动的关键途径。为此提出一种灵活性缺失场景筛选与不确定性分析方法改进相结合的配电网规划研究模型:首先,立足资源视角进行配电网灵活性供需关系建模;其次,基于影子价格理论提出配电网灵活性缺失场景筛选策略,建立筛选指标以描述规划资源、运行约束、场景筛选间闭环关系;然后,将该策略嵌入配电网-多资源两阶段联合规划模型,一阶段考虑投资成本最优,二阶段协调运行及灵活性综合成本期望;将规划模型重构并于改进场景概率驱动型分布鲁棒优化(ISPD-DRO)框架下求解,其优势在于实现了概率优化求解与场景动态更新的有机统一;最后经算例分析验证所提模型在提升决策经济性及配电网灵活性层面的优势。 展开更多
关键词 需求侧灵活性资源 影子价格理论 场景筛选 改进场景概率驱动型分布鲁棒优化 配电网规划
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俗语警句情景下的概率论研究
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作者 赵选泽 周小辉 《高等数学研究》 2024年第3期107-110,F0003,12,共6页
把概率论里枯燥艰涩的理论知识与丰富多彩的生活实践相结合,理论联系实际,用概率论的基础知识和基本原理去阐释挖掘俗语警句中所蕴涵的人生哲理、科学思想和文化渊源,揭示“数学”、“哲学”与“文化”的关系,进而激发学生学习的兴趣和... 把概率论里枯燥艰涩的理论知识与丰富多彩的生活实践相结合,理论联系实际,用概率论的基础知识和基本原理去阐释挖掘俗语警句中所蕴涵的人生哲理、科学思想和文化渊源,揭示“数学”、“哲学”与“文化”的关系,进而激发学生学习的兴趣和热情,提高学生学习概率论的效率. 展开更多
关键词 概率论 俗语警句 贝叶斯公式 几何分布
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Reliability analysis of monotone coherent multi-state systems based on Bayesian networks 被引量:2
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作者 Binghua Song Zhongbao Zhou +2 位作者 Chaoqun Ma Jinglun Zhou Shaofeng Geng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第6期1326-1335,共10页
The Bayesian networks (BNs) provide a robust probabilistic method of reasoning under uncertainty and have been successfully applied to a variety of real-world tasks. Aiming to explore the capabilities of the BN formal... The Bayesian networks (BNs) provide a robust probabilistic method of reasoning under uncertainty and have been successfully applied to a variety of real-world tasks. Aiming to explore the capabilities of the BN formalism in reliability analysis of monotone coherent multi-state systems, the BNs are compared with a popular tool for reliability analysis of monotone coherent multi-state systems, namely the multi-state fault trees (MFTs). It is shown that any MFT can be directly mapped into BN and the basic inference techniques on the latter may be used to obtain classical parameters computed from the former (i.e. probability distribution of top variable, minimal upper vectors and maximum lower vectors for any performance level, importance measures of components). Furthermore, some additional information can be obtained by using BN, both at the modeling and analysis level. At the modeling level, several restrictive assumptions implicit in the MFT methodology can be removed and various kinds of dependencies among components can be accommodated. At the analysis level, a general diagnostic analysis can be performed. The comparison of these methods is illustrated by an example of the water supply system. © 2016 Beijing Institute of Aerospace Information. 展开更多
关键词 Bayesian networks probability distributions RELIABILITY Reliability theory VECTORS Water supply Water supply systems
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A new probability distribution model of turbulent irradiance based on Born perturbation theory 被引量:1
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作者 WANG HongXing LIU Min +2 位作者 HU Hao WANG Qian LIU XiGuo 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第10期1811-1818,共8页
The subject of the PDF (Probability Density Function) of the irradiance fluctuations in a turbulent atmosphere is still unsettled.Theory reliably describes the behavior in the weak turbulence regime,but theoretical de... The subject of the PDF (Probability Density Function) of the irradiance fluctuations in a turbulent atmosphere is still unsettled.Theory reliably describes the behavior in the weak turbulence regime,but theoretical description in the strong and whole turbulence regimes are still controversial.Based on Born perturbation theory,the physical manifestations and correlations of three typical PDF models (Rice-Nakagami,exponential-Bessel and negative-exponential distribution) were theoretically analyzed.It is shown that these models can be derived by separately making circular-Gaussian,strong-turbulence and strong-turbulence-circular-Gaussian approximations in Born perturbation theory,which denies the viewpoint that the Rice-Nakagami model is only applicable in the extremely weak turbulence regime and provides theoretical arguments for choosing rational models in practical applications.In addition,a common shortcoming of the three models is that they are all approximations.A new model,called the Maclaurin-spread distribution,is proposed without any approximation except for assuming the correlation coefficient to be zero.So,it is considered that the new model can exactly reflect the Born perturbation theory.Simulated results prove the accuracy of this new model. 展开更多
关键词 optical propagation atmospheric turbulence irradiance scintillation Born perturbation theory probability density function Maclaurin-spread distribution
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COOPERATIVE MIMO SPECTRUM SENSING BASED ON RANDOM MATRIX THEORY
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作者 Wang Lei Zheng Baoyu +1 位作者 Cui Jingwu Chen Chao 《Journal of Electronics(China)》 2010年第2期190-196,共7页
Random Matrix Theory (RMT) is a valuable tool for describing the asymptotic behavior of multiple systems,especially for large matrices. In this paper,using asymptotic random matrix theory,a new cooperative Multiple-In... Random Matrix Theory (RMT) is a valuable tool for describing the asymptotic behavior of multiple systems,especially for large matrices. In this paper,using asymptotic random matrix theory,a new cooperative Multiple-Input Multiple-Output (MIMO) scheme for spectrum sensing is proposed,which shows how asymptotic free property of random matrices and the property of Wishart distribution can be used to assist spectrum sensing for Cognitive Radios (CRs). Simulations over Rayleigh fading and AWGN channels demonstrate the proposed scheme has better detection performance compared with the energy detection techniques even in the case of a small sample of observations. 展开更多
关键词 Cognitive Radio (CR) network Spectrum sensing Random Matrix theory (RMT) Free probability Wishart distribution
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Fuzzy stochastic damage mechanics(FSDM) based on fuzzy auto-adaptive control theory
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作者 Ya-jun WANG Wo-hua ZHANG +1 位作者 Chu-han ZHANG Feng JIN 《Water Science and Engineering》 EI CAS 2012年第2期230-242,共13页
In order to fully interpret and describe damage mechanics, the origin and development of fuzzy stochastic damage mechanics were introduced based on the analysis of the harmony of damage, probability, and fuzzy members... In order to fully interpret and describe damage mechanics, the origin and development of fuzzy stochastic damage mechanics were introduced based on the analysis of the harmony of damage, probability, and fuzzy membership in the interval of [0,1]. In a complete normed linear space, it was proven that a generalized damage field can be simulated through β probability distribution. Three kinds of fuzzy behaviors of damage variables were formulated and explained through analysis of the generalized uncertainty of damage variables and the establishment of a fuzzy functional expression. Corresponding fuzzy mapping distributions, namely, the half-depressed distribution, swing distribution, and combined swing distribution, which can simulate varying fuzzy evolution in diverse stochastic damage situations, were set up. Furthermore, through demonstration of the generalized probabilistic characteristics of damage variables, the cumulative distribution function and probability density function of fuzzy stochastic damage variables, which show β probability distribution, were modified according to the expansion principle. The three-dimensional fuzzy stochastic damage mechanical behaviors of the Longtan rolled-concrete dam were examined with the self-developed fuzzy stochastic damage finite element program. The statistical correlation and non-normality of random field parameters were considered comprehensively in the fuzzy stochastic damage model described in this paper. The results show that an initial damage field based on the comprehensive statistical evaluation helps to avoid many difficulties in the establishment of experiments and numerical algorithms for damage mechanics analysis. 展开更多
关键词 β probability distribution fuzzy membership of damage variable fuzzy auto-adaptive theory fuzzy stochastic finite element method fuzzy stochastic damage
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基于多态模糊贝叶斯网络的城市燃气管道事故风险预测与诊断研究 被引量:3
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作者 瞿英 王旭茗 +1 位作者 王玉恒 张静怡 《河北科技大学学报》 CAS 北大核心 2023年第4期411-420,共10页
为了评估城市燃气管道系统的风险程度,给后续预防工作提供参考,提出了基于多态模糊贝叶斯网络的燃气管道事故风险定量分析方法。首先,基于对86份事故调查报告风险因素的梳理,建立故障树模型,寻求风险隐患和事故之间的映射,并将其转换为... 为了评估城市燃气管道系统的风险程度,给后续预防工作提供参考,提出了基于多态模糊贝叶斯网络的燃气管道事故风险定量分析方法。首先,基于对86份事故调查报告风险因素的梳理,建立故障树模型,寻求风险隐患和事故之间的映射,并将其转换为贝叶斯网络结构;其次,引入模糊集理论与概率分配计算方法,分别得出根节点的先验概率和中间节点的条件概率,根据贝叶斯网络的证据推理原理预测事故发生概率,分析风险重要程度,并反向诊断关键致因要素;最后,将此方法应用于沈阳市“10·21”较大燃气管道事故风险分析。实例验证结果表明,事故一定发生的先验概率为68.8%,验证了风险体系的有效性,且预测与诊断得出的重要风险集合与事故调查报告中分析的直接原因一致。多态模糊贝叶斯网络能够准确评价燃气管道事故风险,并确定关键致险因子,可为城市燃气管道安全管理提供决策参考。 展开更多
关键词 风险评价与失效分析 燃气管道系统 模糊集理论 多态模糊贝叶斯网络 概率分配
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概率统计由线性到非线性的发展 被引量:1
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作者 陈增敬 冯新伟 《数学建模及其应用》 2023年第2期125-134,共10页
概率统计是研究不确定现象的数学学科,它的本质就是从不确定现象中找确定的统计规律.三百多年以来,概率统计不仅推动了数学由确定性数学到随机数学的发展,也为经济、金融、物理、化学和生物等学科的发展提供了有效的计量工具和方法.随... 概率统计是研究不确定现象的数学学科,它的本质就是从不确定现象中找确定的统计规律.三百多年以来,概率统计不仅推动了数学由确定性数学到随机数学的发展,也为经济、金融、物理、化学和生物等学科的发展提供了有效的计量工具和方法.随着大数据、人工智能和经济金融的飞速发展,现代概率统计已不能满足经济和科技发展的需要,发展和创新概率统计,为大数据、人工智能和经济金融提供理论基础和计算方法已是数学家攻克的重点热点问题.为了满足概率统计爱好者的需要,本文简单地介绍了概率统计发展的过程、对科学发展的作用、面临的问题和目前正在开展的新的研究方向,从另一个侧面介绍一下概率统计前世与后生. 展开更多
关键词 概率论 极限定理 金融革命 非线性期望 非线性正态分布
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侧限拉伸对无纺土工布孔径概率分布的影响 被引量:1
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作者 赵文芳 唐晓武 +3 位作者 郭文琪 李柯毅 陈式华 林维康 《长江科学院院报》 CSCD 北大核心 2023年第8期120-126,共7页
为探究无纺土工布孔径在侧向限制的拉伸作用下所受的影响,基于孔径分布的数量概率密度函数,推导了表征筛分颗粒质量分布的概率密度表达式,并考虑受侧限单向拉伸时的无纺布尺寸变化,得出侧限单向拉应变作用下的无纺布孔径累积分布理论公... 为探究无纺土工布孔径在侧向限制的拉伸作用下所受的影响,基于孔径分布的数量概率密度函数,推导了表征筛分颗粒质量分布的概率密度表达式,并考虑受侧限单向拉伸时的无纺布尺寸变化,得出侧限单向拉应变作用下的无纺布孔径累积分布理论公式。将3种不同厚度的短纤针刺无纺土工布侧边进行限制,单向拉伸至应变为0%、3%、5%和10%后分别取样进行消除静电影响的干筛试验,测量初始及各应变下无纺布孔径分布结果并与理论值对比。结果表明,无纺土工布孔径分布曲线随侧限单向拉应变增加而右移,各个特征孔径均增大,且无纺布孔径随织物厚度增加而减小。相较于筛分颗粒面积分布的累积概率表达式,基于筛分颗粒质量分布的理论孔径累积分布概率表达式更好地预测了干筛试验曲线变化规律。 展开更多
关键词 孔径概率分布 无纺土工布 侧限单向拉伸 孔径累积分布理论 干筛试验 特征孔径
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基于等效建模的风电机组增功技改快速评估方法研究 被引量:1
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作者 李晓辉 贾鑫 +3 位作者 王晓东 杨茂查 贾江涛 李鹏 《风机技术》 2023年第4期18-23,共6页
针对当前风电机组增功技改中存在获取建模参数困难,所建模型精确度不高的问题,提出一种基于等效建模的风电机组增功技改的快速评估方法。采用基于SCADA数据概率统计方法,建立了风电机组控制参数模型;基于翼型数据库与叶素动量理论,建立... 针对当前风电机组增功技改中存在获取建模参数困难,所建模型精确度不高的问题,提出一种基于等效建模的风电机组增功技改的快速评估方法。采用基于SCADA数据概率统计方法,建立了风电机组控制参数模型;基于翼型数据库与叶素动量理论,建立了叶片基本几何模型,采用优化算法,以风电机组特性曲线为目标进行模型优化。利用NREL5MW风电机组对等效建模方法进行验证,得出功率与推力曲线吻合很好。对某2MW风电机组进行等效建模,在等效模型的基础上研究了叶尖加长方法,并对加长的效果进行了气动评估,结果表明通过SCADA数据获取的参数能更好地符合实际机组的运行情况,等效模型能准确模拟出原模型的气动特性,叶尖加长后能显著提高风电机组的年发电量,具有较好的经济效益,是解决风电机组发电效率低、经济效益差的有效方法。 展开更多
关键词 风电机组 等效建模 概率分布 叶素动量理论 叶片加长
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基于受限玻尔兹曼机和粗糙集的风速区间概率预测模型
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作者 于晓要 李娜 《计算机应用与软件》 北大核心 2023年第3期157-166,240,共11页
针对风速的不确定性、时变和非线性特征,提出一种用于风速预测的基于受限玻尔兹曼机和粗糙集理论的区间概率分布学习(Interval Probability Distribution Learning, IPDL)模型。该模型包含一组区间隐藏变量,利用Gibbs抽样和对比散度来... 针对风速的不确定性、时变和非线性特征,提出一种用于风速预测的基于受限玻尔兹曼机和粗糙集理论的区间概率分布学习(Interval Probability Distribution Learning, IPDL)模型。该模型包含一组区间隐藏变量,利用Gibbs抽样和对比散度来获取风速的概率分布,结合模糊Ⅱ型推理系统(Fuzzy Type Ⅱ Inference System, FT2IS),设计一个有监督回归的实值区间深度置信网络(Interval Deep Belief Network, IDBN)。算例结果表明,该方法结合了IPDL和FT2IS的鲁棒性,风速预测性能较好。 展开更多
关键词 受限玻尔兹曼机 粗糙集理论 风速预测 区间概率分布学习 人工神经网络
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Average bit error rate of multi-hop parallel decode-and-forward-based FSO cooperative system with the max–min criterion under the gamma–gamma distribution 被引量:1
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作者 曹天 王平 +3 位作者 郭立新 杨本圣 李晶 杨银堂 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第8期1-5,共5页
The average bit error rate (BER) performance of a free-space optical (FOS) system based on the multi-hop parallel decode-and-forward cooperative communication method with an M-ary phase shift keying subcarrier int... The average bit error rate (BER) performance of a free-space optical (FOS) system based on the multi-hop parallel decode-and-forward cooperative communication method with an M-ary phase shift keying subcarrier intensity modulation is studied systematically. With the max-min criterion as the best path selection scheme, the probability density function and the cumulative distribution function of the gamma-gamma distribution random variable signal-to-noise ratio are derived. The analytical BER expression is then obtained in terms of the Gauss-Laguerre quadrature rule. Monte Carlo simulation is also provided to confirm the validity of the presented average BER model. 展开更多
关键词 Bandwidth Communication channels (information theory) Cooperative communication DECODING distribution functions Intelligent systems Monte Carlo methods Optical communication Phase shift Phase shift keying Phase shifters probability density function probability distributions Signal to noise ratio
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