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probability distribution OF IN-LINE WAVE FORCES ON A PILE IN IRREGULAR WAVES

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Journal of Hydrodynamics 1993年第4期5卷 47-56页

作者： Yu Yu-xiu Zhang Ning-chuan Dalian University of Technology,Dalian 116024,P.R.China

The probability distribution of in-line wave forces on a pile can be mathematically summed up to that of a theory and the assumption of wave period being constant are used and the above probability distribution is simplified to that of a single dimentsion function.The probability density functions of the peak values of total wave forces on a whole vertical pile in irregular waves are derived from that of wave height which is the Rayleigh distribution(deep water wave)or the Kerohovski distribution(shallow water waves)on the base of the Morison Equation.The identification with experimental data shows that such simplification is successful.These distributions are compared with Weibull distribution and Rayleigh distribution and the result shows that the shallow water distribution of wave forces obtained here is the best one and can be used in practice.

关键词： wave forces probability distribution pile irregular waves

A Heuristic Sampling Method for Maintaining the probability distribution

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Journal of Computer Science & Technology 2021年第4期36卷 896-909页

作者： Jiao-Yun Yang Jun-Da Wang Yi-Fang Zhang Wen-Juan Cheng Lian Li Key Laboratory of Knowledge Engineering with Big Data of Ministry of Education Hefei University of Technology Hefei 230601China National Smart EldeTca/re International Science and Technology Coopemtion Base Hefei University of Technology Hefei 230601China School of Computer Science and Information Engirwering Hefei University of TechnologyHefei 230601China School of Mathematics Hefei University of TechnologyHefei 230601China

Sampling is a fundamental method for generating data subsets.As many data analysis methods are developed based on probability distributions,maintaining distributions when sampling can help to ensure good data analysis performance.However,sampling a minimum subset while maintaining probability distributions is still a problem.In this paper,we decompose a joint probability distribution into a product of conditional probabilities based on Bayesian networks and use the chi-square test to formulate a sampling problem that requires that the sampled subset pass the distribution test to ensure the distribution.Furthermore,a heuristic sampling algorithm is proposed to generate the required subset by designing two scoring functions:one based on the chi-square test and the other based on likelihood functions.Experiments on four types of datasets with a size of 60000 show that when the significant difference level,a,is set to 0.05,the algorithm can exclude 99.9%,99.0%,93.1%and 96.7%of the samples based on their Bayesian networks-ASIA,ALARM,HEPAR2,and ANDES,respectively.When subsets of the same size are sampled,the subset generated by our algorithm passes all the distribution tests and the average distribution difference is approximately 0.03;by contrast,the subsets generated by random sampling pass only 83.8%of the tests,and the average distribution difference is approximately 0.24.

关键词： Bayesian network chi-square test sampling probability distribution

Earthquake Magnitude probability and Gamma distribution

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International Journal of Geosciences 2023年第7期14卷 585-602页

作者： Min-Hao Wu Jui-Pin Wang Chia-Ying Sung Department of Civil and Environmental Engineering National University of Kaohsiung Kaohsiung Department of Civil Engineering & Research Center for Hazard Mitigation and Prevention National Central University Taoyuan

The earthquake magnitude probability distribution is one of the underlying input data for certain earthquake analyses, such as probabilistic seismic hazard analysis. Nowadays, the method proposed by McGuire and Arabasz (1990) is commonly used for obtaining the (simulated) earthquake magnitude probability distributions. However, based on the observed earthquake data in 5 regions (Taiwan, Japan, California, Turkey, and Greece), the model did not fit the observation well. Instead, all of the case studies show that using the newly proposed gamma distribution can improve the simulation significantly compared to the conventional method.

关键词： Earthquake Magnitude probability distribution Gamma distribution

Evaluation of probability distribution Functions for Modeling Forest Tree Diameters on Agricultural Landscapes in Ogun State, Nigeria

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Open Journal of Forestry 2022年第4期12卷 432-442页

作者： Adekanmbi Dende Ibrahim Department of Tropical Forestry National University of Agriculture Porto Novo Republic of Benin

The use of probability distribution functions for describing tree diameter at breast height provides useful information for forest resource evaluation and quantification. A series of probability distribution functions have been widely developed and applied for managing forest trees in conventional forest reserves without much consideration for trees outside forest reserves. The aim of this study is to evaluate and propose a suitable probability distribution function for trees in Agricultural landscapes. The study examined 3-parameter lognormal, Lognormal, 3-parameter Gamma, Gamma, 3-parameter Weibull and Weibull distribution functions, using the Maximum Likelihood method for fitting tree diameter at breast height. Three hundred and thirty-two temporary farmlands were randomly selected from which stem diameter of all living trees, with diameter ≥ 10.0 cm, were measured. Results of the statistical analysis showed that the 3-parameter lognormal distribution gave a superior description of the stem diameter with the least values of Anderson Darling (1.627) and Akaike Information Criterion (5962.0) statistics. Hence, the 3-parameter lognormal distribution function was found suitable for the stem diameter of trees in Agricultural landscapes in the study area.

关键词： probability distribution Tree Diameter Agricultural Landscapes Goodness of-Fit Statistics Ogun State

probability distribution of Average Length of Node Path and Its Evolution Trace of Aviation Network of China Based on Complex Network

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Journal of Traffic and Transportation Engineering 2021年第2期9卷 41-52页

作者： Cheng Xiangjun Yang Fang Li Tao School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China

In order to reveal the complex network feature and its evolution principle of aviation network of China,probability distribution and its evolution trace of average length of node path of aviation network of China were researched according to statistics data in years 1988,1994,2001,2008 and 2015 of civil aviation of China.Floyd algorithm to calculate the path length between any two nodes of network was applied and average length of node path of aviation network was obtained according to this algorithm.It was discovered that average length of node path to other nodes had normal distribution function in each year.At meantime,the location parameter and scale parameter of normal distribution function had linear evolution trace.Airline rate was an index to describe the density of airline.It was found that average length of node path of aviation network of China evolved synchronously with airline rate and they had linear relationship.

关键词： Aviation network of China average length of node path probability distribution evolution trace airline rate

A probability distribution of Surface Elevation for Wind Waves in Terms of the Gram-Charlier Series

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China Ocean Engineering 2003年第4期18卷 605-616页

作者：黄传江戴德君王伟钱成春 Physical Oceanography Laboratory Ocean University of China Qingdao 266003 China

Laboratory experiments are conducted to study the probability distribution of surface elevation for wind waves and the convergence is discussed of the Gram-Charlier series in describing the surface elevation distribution. Results show that the agreement between the Gram-Charlier series and the observed distribution becomes better and better as the truncated order of the series increases in a certain range, which is contrary to the phenomenon observed by Huang and Long (1980). It is also shown that the Gram-Charlier series is sensitive to the anomalies in the data set which will make the agreement worse if they are not preprocessed appropriately. Negative values of the probability distribution expressed by the Gram-Charlier series in some ranges of surface elevations are discussed, but the absolute values of the negative values as well as the ranges of their occurrence become smaller gradually as more and mote terms are included. Therefore the negative values will have no evident effect on the form of the whole surface elevation distribution when the series is truncated at higher orders. Furthermore, a simple recurrence formula is obtained to calculate the coefficients of the Gram-Charlier series in order to extend the Gram-Charlier series to high orders conveniently.

关键词： Gram-Charlier series wave surface elevation probability distribution

probability distribution and Their Non-linear Relationship between Node Degree and Clustering Coefficient of Aviation Network of China Based on Complex Network

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Journal of Traffic and Transportation Engineering 2020年第2期8卷 55-62页

作者： Cheng Xiangjun Yu Aihui Chen Xumei School of Traffic&Transportation Beijing Jiaotong UniversityBeijing 100044China Civil Aviation Management Institute of China Beijing 100102China

In order to reveal the complex network feature of aviation network of China,probability distribution of node degree and clustering coefficient of aviation network of China was researched according to statistics data of civil aviation of China.It was verified that node degree had power function probability distribution.Clustering coefficient of nodes with exponential function probability distribution was discovered.It was found that node degree and clustering coefficient had single peak nonlinear relationship.At the left side of the peak,there is no certain relationship between them.At the right side of the peak,clustering coefficient became smaller with the rise of node degree and there was negative exponential function relationship between them by regression analysis.

关键词： Aviation network of China complex network feature probability distribution regression analysis curve fitting

EVALUATION ON LOGISTICS CENTER LOCATION BASED ON probability distribution OF INTERVAL NUMBER

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EVALUATION ON LOGISTICS CENTER LOCATION BASED ON PROBABILITY...

Determination of Basic probability Assignment Based on probability distribution

2005年中国机械工程学会年会

作者： LI Jinying (Dept. of Economic Management, North China Electric power University, 071003)

＜正＞The main indicators that influence the logistics center location are listed. The indicator system composes of qualitative indictors and quantitative indicators. Qualitative indicators are evaluated with expert evaluation model and quantitative indicators are evaluated with index method. Because the information about logistics center location is incomplete for decision-making, a definite number cannot reflect it, in the paper, the logistics center location comprehensive evaluated model is set up which is counting the probability distribution on the basis of considering interval numbers. It makes the evaluation system more practical.

关键词： logistics center location indicator system interval number probability distribution evaluation

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Determination of Basic Probability Assignment Based on Proba...