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Computer Modeling in Engineering & Sciences 2022年第1期130卷 379-396页

作者： Ali Algarni Abdullah M.Almarashi Department of Statistics Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia

In this paper,we propose a new extension of the traditional rayleigh distribution called the modified Kies rayleigh *** new distribution contains one scale and one shape parameter and its hazard rate function can be increasing and *** mathematical properties of the new distribution are derived including quantiles and *** parameters of modified Kies rayleigh distribution are estimated based on progressively Type-II censored *** this purpose,we consider two estimation methods,namely maximum likelihood and maximum product of spacing estimation *** compare the efficiency of the proposed estimators,a simulation study is carried *** show the applicability of the new model as well as the estimation methods,one real data for failure times of software is *** on the empirical parts,we can conclude that the proposed model can be considered as a good model in the field of life testing and reliability analysis compared with other competing models.

关键词： rayleigh distribution modified kies family progressive Type-II censored maximum likelihood estimation maximum product of spacing

VOICE ACTIVITY DETECTION UNDER rayleigh distribution

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Journal of Electronics(China) 2009年第4期26卷 552-556页

作者： Li Yu Chen Jianming Tan Hongzhou School of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China

This paper presents an improved Voice Activity Detection （VAD） algorithm which uses the Signal-to-Noise Ratio （SNR） measure. We assume that noise Power Spectral Density （PSD） in each spectral bin follows a rayleigh distribution. rayleigh distributions with its asymmetric tail characteristics give a better description of the noise PSD distribution than Gaussian distribution. Under this asstlmption, a new threshold updating expression is derived. Since the analytical integral of the false alarm probability, the threshold updating expression can be represented without the inverse complementary error function and low computational complexity is achieved in our system. Experimental results show that the proposed VAD outperforms or at least is comparable with the VAD scheme presented by Davis under several noise environments and has a lower computational complexity.

关键词： Statistical Voice Activity Detection (VAD) Threshold update rayleigh distribution Computational complexity

rayleigh distribution Based Variable Step-Size Constant Modulus Blind Equalization Algorithm

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Rayleigh Distribution Based Variable Step-Size Constant Modu...

Statistical Inference for the Parameter of rayleigh distribution Based on Progressively Type-I Interval Censored Sample

第一届国际测量仪器与测试自动化学术会议

作者： Han Yingge Guo Yecai (Anhui university of science and technology Huainan 232001 China)

＜正＞Aiming at the slow convergence rates of Constant Modulus Algorithm（CMA） and Residual Error based Variable step-size CMA （REVCMA）, a novel rayleigh distribution based on Variable step-size CMA （RDVCMA） is proposed. In this proposed algorithm, the rayleigh distribution function, which has two parameters and whose independent variable is an error function, is used as variable step-size. The convergence rates of the proposed RDVCMA can be improved by regulating its two parameters. We analyze the influence of the two parameters on the convergence rates and give the regulation principle of the two parameters. Simulation tests with telephone channel using 4QAM and 4PSK are carried out, respectively. The simulation results have indicated that the convergence rates of the proposed RDVCMA are faster than those of the CMA and the REVCMA under condition of the same steady state error. Accordingly, rayleigh distribution based Variable step-size CMA （RDVCMA） has better the performance of real time information retrieval and practicability.

关键词： Constant modulus algorithm convergence rates variable step-size rayleigh distribution telephone channel.

来源： cnki会议评论

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Communications in Mathematical Research 2015年第2期31卷 108-118页

作者： Abdalroof M S Zhao Zhi-wen Wang De-hui School of Mathematics Jilin University College of Mathematics Jilin Normal University

In this paper, the estimation of parameters based on a progressively type-I interval censored sample from a rayleigh distribution is studied. Different methods of estimation are discussed. They include mid-point approximation estima- tor, the maximum likelihood estimator, moment estimator, Bayes estimator, sampling adjustment moment estimator, sampling adjustment maximum likelihood estimator and estimator based on percentile. The estimation procedures are discussed in details and compared via Monte Carlo simulations in terms of their biases.

关键词： EM algorithm maximum likelihood estimation moment method Bayesestimation rayleigh distribution

Statistical Inference of Truncated Weibull-rayleigh distribution: Its Properties and Applications

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Open Journal of Modelling and Simulation 2021年第3期9卷 281-298页

作者： Eman H. Khalifa Dina A. Ramadan B. S. El-Desouky Department of Mathematics Faculty of Science Mansoura University Mansoura Egypt

In this paper, we derived a new distribution named as truncated Weibull rayleigh (TW-R) distribution. Its characterization and statistical properties are obtained, such as reliability function, hazard function, revers... 详细信息

In this paper, we derived a new distribution named as truncated Weibull Rayleigh (TW-R) distribution. Its characterization and statistical properties are obtained, such as reliability function, hazard function, reversed hazard rate function, cumulative hazard rate function, quantile function, rth moment, incomplete moments, Rényi and q entropies and order statistic. Parameter estimation is implemented using method of maximum-likelihood estimation and Fisher information matrix is derived. Finally, application of the presented new distribution to a real data representing the failure times of 63 airbcraft Windshield is given and its goodness-of-fit is demonstrated. In addition to, comparisons to other models are implemented to show the flexibility of the presented model.

关键词： rayleigh distribution Truncated Weibull G-Family Moments Entropies Quantile Function Order Statistic Maximum Likelihood Estimator

Parameter Estimations of rayleigh distribution

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Chinese Quarterly Journal of Mathematics 2000年第4期15卷 49-54页

作者：林金官江苏教育学院数学系，江苏南京 210013

设随机变量X服从rayleigh分布，其密度函数为p(x;β)=2x/βe-x^2/β，x＞0,β＞0为参数，对变换群G={gc;gc(x)=c^2x,c＞0}，本文分别在平方损失和熵损失下研究了β在G上的最优同变估计；当β有先验信息时，给出了β的Bayes估计。

关键词： rayleigh distribution transformation group minimum risk equivariant estimations Bayesian estimations

Application of Maximum Entropy Principle to Studying the distribution of Wave Heights in A Random Wave Field

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海洋工程：英文版 2004年第1期18卷 69-78页

作者：周良明郭佩芳王强杜伊 Department of Oceanography

Based on the maximum entropy principle, a probability density function (PDF) is derived for the distribution of wave heights in a random wave field, without any more hypothesis. The present PDF, being a non-rayleigh form, involves two parameters: the average wave height H— and the state parameter γ. The role of γ in the distribution of wave heights is examined. It is found that γ may be a certain measure of sea state. A least square method for determining γ from measured data is proposed. In virtue of the method, the values of γ are determined for three sea states from the data measured in the East China Sea. The present PDF is compared with the well known rayleigh PDF of wave height and it is shown that it much better fits the data than the rayleigh PDF. It is expected that the present PDF would fit some other wave variables, since its derivation is not restricted only to the wave height.

关键词： information entropy wave heights maximum entropy probability density function rayleigh distribution

Analysis and Assessment of Wind Energy Potential of Almukalla in Yemen

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Computers, Materials & Continua 2022年第8期72卷 3113-3129页

作者： Murad A.A.Almekhlafi Fahd N.Al-Wesabi Majdy M.Eltahir Anwer Mustafa Hilal Amin M.El-Kustaban Abdelwahed Motwakel Ishfaq Yaseen Manar Ahmed Hamza Department of Electrical Engineering–Communication Engineering Sana’a UniversityYemen Department of Computer Science King Khalid UniversityMuhayelAseerSaudi Arabia Faculty of Computer and IT Sana’a UniversitySana’aYemen Department of Information Systems King Khalid UniversityMuhayelAseerSaudi Arabia Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia Electronic Department Faculty of EngineeringUniversity of Science and TechnologySana’aYemen

Energy is an essential element for any civilized country’s social and economic development,but the use of fossil fuels and nonrenewable energy forms has many negative impacts on the environment and the *** Republic of Yemen has very good potential to use renewable ***,we find few studies on renewable wind energy in *** the lack of a similar analysis for the coastal city,this research newly investigates wind energy’s potential near the Almukalla area by analyzing wind ***,evaluation,model identification,determination of available energy density,computing the capacity factors for several wind turbines and calculation of wind energy were extracted at three heights of 15,30,and *** wind speeds were obtained only for the currently available data of five recent years,2005–*** study involves a preliminary assessment of Almukalla’s wind energy potential to provide a primary base and useful insights for wind engineers and *** research aims to provide useful assessment of the potential of wind energy in Almukalla for developing wind energy and an efficient wind *** Weibull distribution shows a perfect approximation for estimating the intensity of Yemen’s wind *** on both theWeibullmodel and the results of the annual wind speed data analysis for the study site in Mukalla,the capacity factor for many turbines was also calculated,and the best suitable turbine was *** to the International Wind Energy Rating criteria,Almukalla falls under Category 7,which is,rated“Superb”most of the year.

关键词： Almukalla energy potential rayleigh distribution Weibull distribution wind power density wind speed

Maximum entropy principle and statistical distribution of ocean wave heights

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Acta Oceanologica Sinica 1996年第1期15卷 59-67页

作者： Wu Kejian and Sun Fu Institute of Physical Oceanography Ocean University of Qingdao Qingdao 266003 China Laboratory of Physical Oceanography Ocean University of Qingdao Qingdao 266003 China

This paper concerns an application of a popular existing law, the maximum entropy principle, to the study of statistical distribution of the ocean wave heights. Under two proper premisses. a conclusion that the wave heights obey the Weibull distribution is drawn by making use of the maximum entropy principle. From this result, we hold that the intnnsic departures using the rayleigh distribution to describe The realistic wave height must exist, and the Weibull distribution usually used as an empirical one has profound origin in physics. The Gluhovskli's empirical wave heights distribution relying on water depth is also discussed briefly, and a possible physical explanation associated with the maximum entropy principle is carried out.

关键词： Entropy rayleigh distribution Weibull distribution

A Statistical Analysis of Wind Speed and Power Density Based on Weibull and rayleigh Models of Jumla, Nepal

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Energy and Power Engineering 2016年第7期8卷 271-282页

作者： Ayush Parajuli Department of Mechanical Engineering Pulchowk Campus Tribhuwan University Lalitpur Nepal

In the present study, wind speed data of Jumla, Nepal have been statistically analyzed. For this purpose, the daily averaged wind speed data for 10 year period (2004-2014: 2012 excluded) provided by Department of Hydrology and Meteorology (DHM) was analyzed to estimate wind power density. Wind speed as high as 18 m/s was recorded at height of 10 m. Annual mean wind speed was ascertained to be decreasing from 7.35 m/s in 2004 to 5.13 m/s in 2014 as a consequence of Global Climate Change. This is a subject of concern looking at government’s plan to harness wind energy. Monthly wind speed plot shows that the fastest wind speed is generally in month of June (Monsoon Season) and slowest in December/January (Winter Season). Results presented Weibull distribution to fit measured probability distribution better than the rayleigh distribution for whole years in High altitude region of Nepal. Average value of wind power density based on mean and root mean cube seed approaches were 131.31 W/m2/year and 184.93 W/m2/year respectively indicating that Jumla stands in class III. Weibull distribution shows a good approximation for estimation of power density with maximum error of 3.68% when root mean cube speed is taken as reference.

关键词： Mean Wind Speed rayleigh distribution Weibull distribution Wind Power Density