A research on a following day load simulation method based on weather forecast parameters

2015 ◽  
Vol 103 ◽  
pp. 691-704 ◽  
Author(s):  
Nianping Li ◽  
Kuan Wang ◽  
Jianlin Cheng
2020 ◽  
pp. 55-74
Author(s):  
Chris Bleakley

Chapter 4 tells the story of numerical weather forecasting from its inception to today’s supercomputing algorithms. In 1922, Lewis Fry Richardson proposed that, since the atmosphere is subject to the laws of physics, future weather can be predicted by means of algorithmic calculations. His attempt at forecasting a single day’s weather by means of manual calculations took several months. In the late 1940s, John von Neumann resurrected Richardson’s idea and launched a project to conduct the first weather forecast by computer. The world’s first operational electronic computer – ENIAC - completed a 24-hour forecast in just one day. It appeared that accurate forecasting simply required faster computers. In 1969, Edward Lorenz discovered that tiny errors in weather measurements can accumulate during numerical forecasting to produce large errors. The so-called Butterfly Effect was alleviated by the Monte Carlo simulation method invented by Stanislaw Ulam for particle physics.


2012 ◽  
Vol 522 ◽  
pp. 297-301
Author(s):  
Yue Feng Li ◽  
Xu Dong Pan ◽  
Guang Lin Wang

The curve intensity of deddendum plays a significant role in gear strength design. Due to the complicated shape of gears, traditional method utilizes the cantilever beam model adds the concentrated load at a fixed point and then revises it by coordinating with different factors so as to calculate the gears the curve intensity of deddendum. In this paper, based on evolute formulas, a methodology about finite element analysis was used for establishing the accurate tooth profile model of the evolute cylinder gear. The moving load was added by programming and the regularity that the amplitude of load changes with the position of the point of application in a tooth meshing cycle was determined. Based on proposed model, this paper provides the variation regularity of the magnitude of the stress of deddendum by simulation.


Author(s):  
Jorge Luis Aguilar-Marin ◽  
Julio Cesar Vergara-Vázquez ◽  
Jorge Gabriel Padilla-Cantero ◽  
Daniel Hernández-González

One of the parameters considered in the design of transmission lines is the distribution of its generated electric field. The following article presents a reference methodology that allows obtaining the electric field on the right-of-way of a High Voltage Alternating Current (HVAC) overhead transmission line, the methodology is developed based on the Load Simulation Method (MSC) and the Image Method. The results obtained present a difference of less than 2%. In this way a case study of a 230 kV HVAC double circuit transmission line presented, an optimization of the phases of the transmission line circuits is carried out to determine the most efficient configuration for obtaining the electric field density. The results obtained allow a configuration of n circuits, admitting the different nominal voltages of the HVAC lines.


2009 ◽  
Vol 52 (9) ◽  
pp. 2576-2584 ◽  
Author(s):  
Min Li ◽  
WeiMin Chen ◽  
MingChun Wang ◽  
LiJie Jia

Methodology ◽  
2017 ◽  
Vol 13 (1) ◽  
pp. 9-22 ◽  
Author(s):  
Pablo Livacic-Rojas ◽  
Guillermo Vallejo ◽  
Paula Fernández ◽  
Ellián Tuero-Herrero

Abstract. Low precision of the inferences of data analyzed with univariate or multivariate models of the Analysis of Variance (ANOVA) in repeated-measures design is associated to the absence of normality distribution of data, nonspherical covariance structures and free variation of the variance and covariance, the lack of knowledge of the error structure underlying the data, and the wrong choice of covariance structure from different selectors. In this study, levels of statistical power presented the Modified Brown Forsythe (MBF) and two procedures with the Mixed-Model Approaches (the Akaike’s Criterion, the Correctly Identified Model [CIM]) are compared. The data were analyzed using Monte Carlo simulation method with the statistical package SAS 9.2, a split-plot design, and considering six manipulated variables. The results show that the procedures exhibit high statistical power levels for within and interactional effects, and moderate and low levels for the between-groups effects under the different conditions analyzed. For the latter, only the Modified Brown Forsythe shows high level of power mainly for groups with 30 cases and Unstructured (UN) and Autoregressive Heterogeneity (ARH) matrices. For this reason, we recommend using this procedure since it exhibits higher levels of power for all effects and does not require a matrix type that underlies the structure of the data. Future research needs to be done in order to compare the power with corrected selectors using single-level and multilevel designs for fixed and random effects.


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