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Evaluation of Some Weibull parameter estimation methods for Characterizing Stem Diameter Distribution in a Tropical Mixed Forest of Southern Nigeria

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Journal of Statistical Science and Application 2016年第6期4卷 257-275页

作者： A.A. Adeyemi P.O. Adesoye Department of Forestry and Wildlife Technology Federal University of Technology Owerri Nigeria Department of Forest Resources Management University oflbadan Nigeria

Stem diameter distribution information is useful in forest management planning. Weibull function is flexible, and has been used in characterising diameter distributions, especially in single-species planted stands, the world over. We evaluated some Weibull parameter estimation methods for stem diameter characterisation in （Oban） multi-species Forest in southern Nigeria. Four study sites （Aking, Ekang, Erokut and Ekuri） were selected. Four 2 km-long transects situated at 600 m apart were laid in each location. Five 50m x 50m plots were alternately laid along each transect at 400 m apart （20 plots/location） using systematic sampling technique. Tree growth variables： diameter at breast height （Dbh）, diameters at the base, middle and merchantable limit, total height, merchantable height, stem straightness, crown length and crown diameter were measured on all trees 〉 10 cm to compute model response variables such as mean diameters, basal area and stem volume. Weibull parameters estimation methods used were： moment-based, percentile-based, hybrid and maximum-likelihood （ML）. Data were analysed using descriptive statistics, regression models and ANOVA at α0.05. Percentile-based method was the best for Weibull [location （a）, scale （b） and shape （c）] parameters estimations with mLogL = 116.66±21.89, while hybrid method was least-suitable （mLogL = 690.14±128.81） for Weibull parameters estimations. Quadratic mean diameter （Dq） was the only suitable predictor of Weibull parameters in Oban Forest.

关键词： Diameter distribution parameter estimation methods prediction models

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Understanding lithium-ion battery management systems in electric vehicles: Environmental and health impacts, comparative study, and future trends: A review

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RESULTS IN ENGINEERING 2024年 24卷

作者： Suganya, R. Joseph, L. M. I. Leo Kollem, Sreedhar SR Univ Sch Engn Dept ECE Warangal 506371 Telangana India

The future of transportation is moving toward electric vehicles (EVs), driven by the global demand for sustainability. At the core of EV technology is the Battery Management System (BMS), which plays a vital role in ensuring the safety, efficiency, and longevity of batteries. Lithium-ion batteries (LIBs) are key to EV performance, and ongoing advances are enhancing their durability and adaptability to variations in temperature, voltage, and other internal parameters. This review aims to support researchers and academics by providing a deeper understanding of the environmental and health impact of EVs. Additionally, the article offers a comprehensive analysis of various algorithms used for parameter estimation in BMS, discussing their advantages, limitations, and practical implications. It also addresses key challenges in EV adoption, such as range anxiety and the development of charging infrastructure. By exploring these aspects, the review provides valuable information on improving BMS efficiency and battery technologies, supporting the future growth of cleaner and more sustainable electric transportation.

关键词： Battery management systems EV battery types Electric motors parameter estimation methods Electric vehicles

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Comparison of four methods for parameter estimation of mono-and multi-junction photovoltaic devices using experimental data

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RENEWABLE & SUSTAINABLE ENERGY REVIEWS 2018年第Part2期81卷 2823-2838页

作者： Penaranda Chenche, Luz Elena Hernandez Mendoza, Oscar Saul Bandarra Filho, Enio Pedone Univ Fed Uberlandia Sch Mech Engn Uberlandia MG Brazil

The present work analyses four methods used to estimate the physical properties of photovoltaic devices for a single diode model. Two of the most efficient photovoltaic technologies-mono-and multi-junction devices-are used under different temperature and solar radiation conditions for comparing the applicability of each method. Three of the four parameter estimation methods are analytic and the remaining one uses an algorithm for the optimization of non-linear problems, i.e., the generalized reduced gradient. The different methods are summarized and a comparative analysis is performed using experimental data obtained from the literature, highlighting the advantages and disadvantages of each method. Criteria such as the mean absolute percentage error, the coefficient of determination, the absolute error in current calculated at the maximum power point, and computational cost are used. Accordingly, it is concluded that, for all the methods considered in this study, the best accuracy is obtained from simulations using the method proposed by Blas et al. [34] applied to mono-junction modules, and the method proposed by Xiao et al. [39] to multi-junction devices.

关键词： Photovoltaic devices Solar cells Multi-junction Mono-junction parameter estimation methods

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Compressive narrowband interference detection and parameter estimation in direct sequence spread spectrum communication

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IET SIGNAL PROCESSING 2022年第1期16卷 14-25页

作者： Shi, Zengkai Zhang, Yongshun Qian, Zhaoyong Sun, Xiaoshuang Ma, Xiangtai Space Engn Univ Dept Space Informat Bayi Rd Beijing 101416 Peoples R China PLA Unit 32039 Beijing Peoples R China

The Shannon-Nyquist sampling theorem that is based on narrowband interference (NBI) detection and parameter estimation methods in direct sequence spread spectrum (DSSS) communication is limited by the high sampling rate. Compressive sensing (CS) is adopted to address the problem. But it will change the signal nature, which leads to the unavailability of Shannon-Nyquist sampling theorem-based interference detection and parameter estimation methods. According to the different posterior probability distribution features of NBI, DSSS signal, and noise in compressed domain, a posterior probability model of whether NBI exists in the received signal is constructed by using the compressed measurements. The posterior probability that whether NBI exists in the received signal is employed as the feature parameters of NBI detection and parameter estimation. With the feature parameters detected, NBI detection can be achieved and the edge location of NBI components can be located. The relationship between the edge location of NBI components and the edge frequency of NBI is constructed, which will contribute to estimate the NBI edge frequency. The numerical simulation results demonstrate that the proposed method can effectively achieve NBI detection and parameter estimation in the compressed domain and it performs significantly better than the other existing methods.

关键词： parameter estimation methods compressive sensing ShannonNyquist sampling theorem edge location NBI edge frequency NBI detection compressed sensing parameter estimation radiofrequency interference compressed domain signal reconstruction spread spectrum communication signal nature different posterior probability distribution features compressed measurements direct sequence spread spectrum communication signal sampling probability DSSS signal NBI components received signal posterior probability model feature parameters

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On the wind resource in Algeria: Probability distributions evaluation

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART A-JOURNAL OF POWER AND ENERGY 2021年第5期235卷 1187-1204页

作者： Ounis, Houdayfa Aries, Nawel CDER Ctr Dev Energies Renouvelables BP 62Route Observ Bouzar Algiers 16340 Algeria CNRS UMR 6027 IRDL Inst Rech Dupuy Lome Lorient France

The present study aims to present a contribution to the wind resource assessment in Algeria using ERA-Interim reanalysis. Firstly, the ERA-Interim reanalysis 10 m wind speed data are considered for the elaboration of the mean annual 10 m wind speed map for a period starting from 01-01-2000 to 31-12-2017. Moreover, the present study intends to highlight the importance of the descriptive statistics other than the mean in wind resource assessment. On the other hand, this study aims also to select the proper probability distribution for the wind resource assessment in Algeria. Therefore, nine probability distributions were considered, namely: Weibull, Gamma, Inverse Gaussian, Log Normal, Gumbel, Generalized Extreme Value (GEV), Nakagami, Generalized Logistic and Pearson III. Furthermore, in combination with the distribution, three parameter estimation methods were considered, namely, Method of Moment, Maximum Likelihood Method and L-Moment Method. The study showed that Algeria has several wind behaviours due to the diversified topographic, geographic and climatic properties. Moreover, the annual mean 10 m wind speed map showed that the wind speed varies from 2.3 to 5.3 m/s, where 73% of the wind speeds are above 3 m/s. The map also showed that the Algerian Sahara is windiest region, while, the northern fringe envelopes the lowest wind speeds. In addition, it has been shown that the study of the mean wind speeds for the evaluation of the wind potential alone is not enough, and other descriptive statistics must be considered. On the other hand, among the nine considered distribution, it appears that the GEV is the most appropriate probability distribution. Whereas, the Weibull distribution showed its performance only in regions with high wind speeds, which, implies that this probability distribution should not be generalized in the study of the wind speed in Algeria.

关键词： Wind resource assessment era-interim reanalysis wind speed map descriptive statistics probability distribution parameter estimation methods

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New trilobular geometry using advanced materials for experimentally validated enhanced heat transfer in shallow geothermal applications

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RENEWABLE ENERGY 2024年 222卷

作者： Urchueguia, Javier F. Badenes, Borja Pla, Miguel A. Mateo Armengot, Bruno Javadi, Hossein Univ Politecn Valencia UPV Inst Informat & Commun Technol ITACA Informat & Commun Technol Versus Climate Change IC Camino Vera s-n Valencia 46022 Spain

The Adapted Conductivity Trilobular (ACT) design, comprising an up -flow central pipe and three satellite downward pipes, represents a novel configuration of a borehole heat exchanger. The novelty lies not only in the geometry of the heat exchanger, but also in the use of materials perfectly adapted to the thermal use for which they have been specified. The central pipe is constructed of a composite bilayer material with very low thermal conductivity, whereas the satellite pipes are based on a novel highly conductive plastic material. The primary objective behind this design was to simplify installation, by using essentially the same drilling and grouting methods used for conventional single -U or double -U borehole heat exchangers. In response to the rising demand for more efficient and affordable ground heat exchangers to be connected to Ground Source Heat Pump (GSHP) systems, this innovation was one of the promising outcomes of the GEOCOND European project. To assess ACT performance, the Geothermal Laboratory on the campus of the Universitat Politecnica de Valencia conducted a number of thermal response tests (TRTs), the experimental results of which are collected and analyzed in this paper. Additionally, a modified version of the Composite Two Region Line Source modeling scheme is described and used to assess the experimental data. A total of four demonstration boreholes - two single -U baseline and two ACT boreholes - have been tested. The experimental investigation using the C2RLS methodology reveals that the ACT configuration has a significantly lower thermal than the typical BHE arrangement and allows a greater specific heat injection rate. Specifically, a borehole resistance drop from 0.149 (m.K)/W to 0.07 (m.K)/W allowing higher injection rates to be achieved without an unsustainable increase in ground temperature. These findings may have significant implications for the development of more efficient and cost-effective GSHP systems.

关键词： Shallow geothermal energy Ground source heat pumps Thermal response test Infinite line-source method Two-region composite line-source method Borehole resistance parameter estimation methods

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Marshall-Olkin distributions: a bibliometric study

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SCIENTOMETRICS 2021年第11期126卷 9005-9029页

作者： Jesus Gonzalez-Hernandez, Isidro Granillo-Macias, Rafael Rondero-Guerrero, Carlos Simon-Marmolejo, Isaias Autonomous Univ Hidalgo State Dept Ind Engn Ciudad Sahagun Mexico Autonomous Univ Hidalgo State Dept Math Mineral De La Reforma Puchuca Mexico

Recently, there has been a growing interest among statistical researchers to develop new probability distributions, adding one or more parameters to previously existing ones. In this article, we describe a bibliometric analysis carried out to show the evolution of various models based on the seminal model of (Marshall and Olkin, Biometrika. 1997). This method allows us to explore and analyze large volumes of scientific data through performance indicators to identify the main contributions of authors, universities, and journals in terms of productivity, citations, and bibliographic coupling. The analysis was performed using the Bibliometrix R-package tool. The sample of analyzed data was based on articles indexed in the main collection of the Web of Science and Scopus between 1997 and 2021. This work also includes an overview of the methodology used, the corresponding quantitative analyses, a visualization of networks of collaboration and co-citations, as well as a description of the topic trends. In total, 131 articles were analyzed, which were published in 67 journals. Two journals published 17% of the manuscripts analyzed in this work. We identified 238 separate authors who have participated in the development of this research topic. In 2020, 49% of the authors presented new distributions, where their proposed models included up to six parameters. The publications were grouped into 20 collaborative groups of which Groups 1 and 2 are dominant in the development of new models. Thus, 24% of the publications analyzed belong to two researchers who lead these two groups. To show the flexibility of the new distributions, the authors apply their models using at least two sets of real-world data to show their potentiality. This article gives a broad overview of different generalizations of the Marshall-Olkin model and will be of great help to those interested in this line of research.

关键词： Bibliometric analysis Marshall-Olkin distribution parameter estimation methods

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Adapted composite two-region line source methods for evaluation of borehole heat exchangers with advanced materials

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APPLIED THERMAL ENGINEERING 2023年第1期231卷

作者： Urchueguia, Javier F. badenes, Borja Javadi, Hossein Mateo, Miguel Angel Armengot, Bruno Univ Politecn Valencia Inst Aplicac Comunicac Avanzadas ITACA IGT Vs Climate Change Res Grp Camino Vera S-N Valencia 46022 Spain

The results of a large number of Thermal Response Tests (TRTs) performed on four different borehole heat exchangers (BHEs) were analyzed to explore the effect of the novel grouting and plastic pipe materials developed in a previous project on their thermal performance. For this purpose, two versions of the composite two-region line source approach have been adapted for its use for evaluating BHEs in practical situations, allowing us to obtain more comprehensive and consistent information on key thermal parameters of ground and fillers. We develop a scheme that combines the composite two-region model with unsteady TRT injection data to avoid some shortcomings that have appeared in previous implementations of this approach. Our new method enables us to obtain parameters otherwise difficult to obtain, such as the diffusivities, heat capacities, and conductivities of ground and grout. In comparison with standard line source based analysis, it allows to improve and enrich TRT execution, with a reduction in the test time required, lower uncertainties of the parameters obtained, and a deeper understanding of the thermal properties of the grout, ground, and borehole heat exchanger as all estimates are correlated to actual physical, mensurable soil and ground properties, which allows independent critical revision and check against alternative estimation methods.

关键词： Shallow geothermal energy Thermal Response Test Infinite line-source method Two-region composite line-source method Borehole resistance parameter estimation methods

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Fast estimation of high-order motion parameters for real-time ISAR imaging

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IET RADAR SONAR AND NAVIGATION 2019年第12期13卷 2244-2254页

作者： Xue, Jiayin Zhang, Qinyu Wang, Ye Gu, Shushi Harbin Inst Technol Shenzhen Elect & Informat Engn Dept Shenzhen 518055 Peoples R China Pengcheng Lab Shenzhen 518052 Peoples R China

The inverse synthetic aperture radar (ISAR) technique is an important tool for target recognition and classification;thus, the high-quality and real-time performance are two essential indicators for ISAR imaging. Based on the classical range-Doppler principle, the motion compensation is the prerequisite step for the subsequent imaging processing. Due to the non-cooperative characteristic of the target, the unknown moving parameters are required to be well estimated. Generally, the translational motion of the target can be accurately described by two-order dynamic parameters. However, the most parameter estimation methods can only estimate the one-order parameter, while the common high-order estimation methods require priori knowledge and are complex to implement. Aiming at this issue, the authors propose a high-order symmetric accumulated cross-correlation method to realise the rapid and accurate estimation of the motion parameters with no requirement of priori knowledge. It takes the advantage of the symmetric accumulation manner to offset the phase errors and optimise the computational complexity simultaneously, and then formulates the estimation to solve the least-square problem. Experimental results verify that the proposed method shows distinct advantages on achieving the high-accuracy and low-complexity parameter estimation, which is highly conductive to realise the high-quality motion compensation for real-time ISAR imaging.

关键词： correlation methods motion compensation synthetic aperture radar radar imaging parameter estimation least squares approximations computational complexity high-order motion parameters real-time ISAR imaging inverse synthetic aperture radar technique target recognition classification real-time performance essential indicators classical range-Doppler principle prerequisite step subsequent imaging processing noncooperative characteristic unknown moving parameters translational motion two-order dynamic parameters parameter estimation methods one-order parameter common high-order estimation methods priori knowledge high-order symmetric accumulated cross-correlation method rapid estimation symmetric accumulation manner low-complexity parameter estimation high-quality motion compensation

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Deep assessment of wind speed distribution models: A case study of four sites in Algeria

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ENERGY CONVERSION AND MANAGEMENT 2018年 155卷 78-90页

作者： Aries, Nawel Boudia, Sidi Mohammed Ounis, Houdayfa CDER BP 62 Route Observ Bouzareah Algiers 16340 Algeria

The aim of this study is to assess the accuracy of different probability functions for modeling wind speed distribution at four locations, distributed over Algeria, to minimize the uncertainly in wind resource estimates. Despite mixture models perform better results, their complexity induced us to use in this work eight distributions with a maximum of three parameters, namely Weibull, Gamma, Inverse Gaussian, Log Normal, Gumbel, GEV, Nakagami and Generalized Logistic distribution to model the wind speed, fitted with four parameter estimation methods. In addition to the methods of moments and the maximum likelihood which are commonly used, the power density method and the L-moments method are developed and utilized for the first time in wind resource assessment field, to estimate the parameters of most distributions used in this work. Moreover, two goodness-of-fit tests based on the coefficient of determination and the root mean square error, are conducted in order to select good fitting probability distribution functions. According to the coefficient of determination and the root mean square error, the GEV and Gamma are the most appropriate, compared to the others used distributions. Furthermore, the L-moments method is the most effective one, among the used parameter estimators, followed by the maximum likelihood method. On the other hand, in term of power density error, different results were found, where the Power Density Method gave the best results with the Gamma, Inverse Gaussian and Log Normal distributions. Otherwise, owing to the difference in the wind characteristics for each studied site, it can be stated that to minimize the uncertainty in wind resource estimates, it is important to determine the method that gives the best parameters for each distribution.

关键词： Wind speed Probability density function parameter estimation methods Statistical analysis

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