scholarly journals A New Approach of Time Series Variation Based on Power Links and Field Association Words

2020 ◽  
Vol 08 (03) ◽  
pp. 72-85
Author(s):  
Zohair S. Malki ◽  
El-Sayed Atlam ◽  
Talal H. Noor ◽  
Ahmad Reda Alzighaibi ◽  
Ghada Elmarhomy ◽  
...  
2018 ◽  
Vol 7 (2) ◽  
pp. 139-150 ◽  
Author(s):  
Adekunlé Akim Salami ◽  
Ayité Sénah Akoda Ajavon ◽  
Mawugno Koffi Kodjo ◽  
Seydou Ouedraogo ◽  
Koffi-Sa Bédja

In this article, we introduced a new approach based on graphical method (GPM), maximum likelihood method (MLM), energy pattern factor method (EPFM), empirical method of Justus (EMJ), empirical method of Lysen (EML) and moment method (MOM) using the even or odd classes of wind speed series distribution histogram with 1 m/s as bin size to estimate the Weibull parameters. This new approach is compared on the basis of the resulting mean wind speed and its standard deviation using seven reliable statistical indicators (RPE, RMSE, MAPE, MABE, R2, RRMSE and IA). The results indicate that this new approach is adequate to estimate Weibull parameters and can outperform GPM, MLM, EPF, EMJ, EML and MOM which uses all wind speed time series data collected for one period. The study has also found a linear relationship between the Weibull parameters K and C estimated by MLM, EPFM, EMJ, EML and MOM using odd or even class wind speed time series and those obtained by applying these methods to all class (both even and odd bins) wind speed time series. Another interesting feature of this approach is the data size reduction which eventually leads to a reduced processing time.Article History: Received February 16th 2018; Received in revised form May 5th 2018; Accepted May 27th 2018; Available onlineHow to Cite This Article: Salami, A.A., Ajavon, A.S.A., Kodjo, M.K. , Ouedraogo, S. and Bédja, K. (2018) The Use of Odd and Even Class Wind Speed Time Series of Distribution Histogram to Estimate Weibull Parameters. Int. Journal of Renewable Energy Development 7(2), 139-150.https://doi.org/10.14710/ijred.7.2.139-150


2021 ◽  
Vol 115 ◽  
pp. 107917
Author(s):  
Ángel Carmona-Poyato ◽  
Nicolás Luis Fernández-Garcia ◽  
Francisco José Madrid-Cuevas ◽  
Antonio Manuel Durán-Rosal

2021 ◽  
Vol 24 ◽  
pp. 100618
Author(s):  
Philipe Riskalla Leal ◽  
Ricardo José de Paula Souza e Guimarães ◽  
Fábio Dall Cortivo ◽  
Rayana Santos Araújo Palharini ◽  
Milton Kampel

PLoS ONE ◽  
2014 ◽  
Vol 9 (9) ◽  
pp. e106613 ◽  
Author(s):  
Roberto O. Chávez ◽  
Jan G. P. W. Clevers ◽  
Jan Verbesselt ◽  
Paulette I. Naulin ◽  
Martin Herold

Author(s):  
YU-YUN HSU ◽  
SZE-MAN TSE ◽  
BERLIN WU

In recent years, the innovation and improvement of forecasting techniques have caught more and more attention. Especially, in the fields of financial economics, management planning and control, forecasting provides indispensable information in decision-making process. If we merely use the time series with the closing price array to build a forecasting model, a question that arises is: Can the model exhibit the real case honestly? Since, the daily closing price of a stock index is uncertain and indistinct. A decision for biased future trend may result in the danger of huge lost. Moreover, there are many factors that influence daily closing price, such as trading volume and exchange rate, and so on. In this research, we propose a new approach for a bivariate fuzzy time series analysis and forecasting through fuzzy relation equations. An empirical study on closing price and trading volume of a bivariate fuzzy time series model for Taiwan Weighted Stock Index is constructed. The performance of linguistic forecasting and the comparison with the bivariate ARMA model are also illustrated.


2012 ◽  
Vol 51 (4II) ◽  
pp. 493-504 ◽  
Author(s):  
Taseer Salahuddin ◽  
Asad Zaman

In the recent literature, consensus has emerged that poverty is a multidimensional phenomenon; see Alkire and Santos (2010) for a review of the major arguments. Nonetheless, the most widely used measures of poverty remain unidimensional, being based on income or caloric intake cutoffs. The logic for the use of income based measures was that it was only lack of income which led to deprivation—with sufficient income; rational agents would automatically eliminate deprivations in all dimensions in the right sequence of priorities. However, careful studies like Thorbecke (2005) and Banerjee and Duflo (2006) show that this does not happen. Even while malnourished and underfed, the poor spend significant portions of their budgets on festivals, weddings, alcohol, tobacco and other non-essential items. The move from abstract theoretical speculation based on mathematical models of human behaviour to experiments and observations of actual behaviour has led to dramatic changes in the understanding of poverty and how to alleviate it. Some of these insights are encapsulated in a new approach to poverty advocated by Banerjee and Duflo (2011).


Author(s):  
Seng Hansun ◽  
Subanar Subanar

      Abstract— Recently, many soft computing methods have been used and implemented in time series analysis. One of the methods is fuzzy hybrid model which has been designed and developed to improve the accuracy of time series prediction.      Popoola has developed a fuzzy hybrid model which using wavelet transformation as a pre-processing tool, and commonly known as fuzzy-wavelet method. In this thesis, a new approach of fuzzy-wavelet method has been introduced. If in Popoola’s fuzzy-wavelet, a fuzzy inference system is built for each decomposition data, then on the new approach only two fuzzy inference systems will be needed. By that way, the computation needed in time series analysis can be pressed.      The research is continued by making new software that can be used to analyze any given time series data based on the forecasting method applied. As a comparison there are three forecasting methods implemented on the software, i.e. fuzzy conventional method, Popoola’s fuzzy-wavelet, and the new approach of fuzzy-wavelet method. The software can be used in short-term forecasting (single-step forecast) and long-term forecasting. There are some limitation to the software, i.e. maximum data can be predicted is 300, maximum interval can be built is 7, and maximum transformation level can be used is 10. Furthermore, the accuracy and robustness of the proposed method will be compared to the other forecasting methods, so that can give us a brief description about the accuracy and robustness of the proposed method. Keywords—  fuzzy, wavelet, time series, soft computing


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