Nowadays, the use of renewable, green/eco-friendly technologies is attracting the attention of researchers, with a view to overcoming recent challenges that must be faced to guarantee the availability of Electric Vehi...
详细信息
Nowadays, the use of renewable, green/eco-friendly technologies is attracting the attention of researchers, with a view to overcoming recent challenges that must be faced to guarantee the availability of Electric Vehicles (EVs). Therefore, this work proposes a methodology based on Genetic Algorithms (GA) and multivariateregression for estimating and modeling the State of Charge (SOC) in Electric Vehicles. Indeed, the proposal considers the continuous monitoring of six load-related variables that have an influence on the SOC (State of Charge), specifically, the vehicle acceleration, vehicle speed, battery bank temperature, motor RPM, motor current, and motor temperature. Thus, these measurements are evaluated in a structure comprised of a Genetic Algorithm and a multivariateregression model in order to find those relevant signals that better model the State of Charge, as well as the Root Mean Square Error (RMSE). The proposed approach is validated under a real set of data acquired from a self-assembly Electric Vehicle, and the obtained results show a maximum accuracy of approximately 95.5%;thus, this proposed method can be applied as a reliable diagnostic tool in the automotive industry.
The dynamic properties of the rock are very important for the design of geotechnical structures and the modeling of deep drilling. In the present study, the velocity of compressional and shear waves (Vp and Vs) and th...
详细信息
The dynamic properties of the rock are very important for the design of geotechnical structures and the modeling of deep drilling. In the present study, the velocity of compressional and shear waves (Vp and Vs) and the dynamic elastic modulus (Ed) of sandstones were estimated based on index tests using artificial neural network (ANN) and multivariate linear regression analysis (MVLRA) methods. For this purpose, petrographic, physical, mechanical and dynamic tests were performed on 54 specimens. Petrographic results showed that the samples were classified as feldspathic litharenite. The results showed that the Vp/Vs ratio was equal to 1.78. Also, the effect of mineralogy on mechanical properties was more than dynamic properties and the effect of quartz on dynamic properties was more than other minerals. The presented relationships were evaluated using R-squared (R-2), root-mean-square error (RMSE), mean absolute relative prediction error (MARPE), variance account for (VAF) and performance index (PI). The results of the ANN to estimate the Ed, Vp and Vs showed that it is possible to estimate these parameters based on inputs with high accuracy. The accuracy of the ANN was higher than the MVLRA. Estimation of Vs, Vp and Ed by ANN showed correlation coefficients of 0.97, 0.86 and 0.92 and RMSE of 0.10, 0.31, and 3.98, respectively. The ANN was also conservative in predicting these variables, while MVLRA was conservative only in estimating the Vs and Ed of the studied sandstones.
Consider a multivariate linear regression model where the sample size is n and the dimensions of the predictors and the responses are p and m, respectively. We know that the limiting distribution of the likelihood rat...
详细信息
Consider a multivariate linear regression model where the sample size is n and the dimensions of the predictors and the responses are p and m, respectively. We know that the limiting distribution of the likelihood ratio test (LRT) in multivariate linear regressions is different in the case of finite and high dimensions. In traditional multivariate analysis, when the dimension parameters (p, m) are fixed, the limiting distribution of the LRT is a chi 2 distribution. However, in the high-dimensional setting, the chi 2 approximation to the LRT may be invalid. In this paper, based on He et al. (2021), we give the moderate deviation principle (MDP) results for the LRT in a high dimensional setting, where the dimension parameters (p, m) are allowed to increase with the sample size n. The performance of the numerical simulation confirms our results. (c) 2022 Elsevier Inc. All rights reserved.
We focus on an optimization algorithm for a normal-likelihood-based group Lasso in multivariate linear regression. A negative multivariate normal log-likelihood function with a block-norm penalty is used as the object...
详细信息
ISBN:
(纸本)9789811627651;9789811627644
We focus on an optimization algorithm for a normal-likelihood-based group Lasso in multivariate linear regression. A negative multivariate normal log-likelihood function with a block-norm penalty is used as the objective function. A solution for the minimization problem of a quadratic form with a norm penalty is given without using the Karush-Kuhn-Tucker condition. In special cases, the minimization problem can be solved without solving simultaneous equations of the first derivatives. We derive update equations of a coordinate descent algorithm for minimizing the objective function. Further, by using the result of the special case, we also derive update equations of an iterative thresholding algorithm for minimizing the objective function.
We propose a likelihood-based variable selection method for selecting explanatory variables in normality-assumed multivariate linear regression contexts. The proposed method is reasonably fast in terms of run-time, an...
详细信息
ISBN:
(纸本)9789811627651;9789811627644
We propose a likelihood-based variable selection method for selecting explanatory variables in normality-assumed multivariate linear regression contexts. The proposed method is reasonably fast in terms of run-time, and it has a selection consistencywhen the sample size always tends to infinity, but the number of response and explanatory variables does not necessarily have to tend to infinity. It can be expected that the probability of selecting the true subset by the proposed method is high under a moderate sample size.
This paper is concerned with the selection of explanatory variables in multivariate linear regression. The Akaike's information criterion and the C-p criterion cannot perform in high-dimensional situations such th...
详细信息
This paper is concerned with the selection of explanatory variables in multivariate linear regression. The Akaike's information criterion and the C-p criterion cannot perform in high-dimensional situations such that the dimension of a vector stacked with response variables exceeds the sample size. To overcome this, we consider two variable selection criteria based on an L-2 squared distance with a weighted matrix, namely the scalar-type generalized C-p criterion and the ridge-type generalized C-p criterion. We clarify conditions for their consistency under a hybrid-ultra-high-dimensional asymptotic framework such that the sample size always goes to infinity but the number of response variables may not go to infinity. Numerical experiments show that the probabilities of selecting the true subset by criteria satisfying consistency conditions are high even when the dimension is larger than the sample size. Finally, we illuminate the practical utility of these criteria using empirical data.
We put forward a variable selection method for selecting explanatory variables in a normality-assumed multivariate linear regression. It is cumbersome to calculate variable selection criteria for all subsets of explan...
详细信息
We put forward a variable selection method for selecting explanatory variables in a normality-assumed multivariate linear regression. It is cumbersome to calculate variable selection criteria for all subsets of explanatory variables when the number of explanatory variables is large. Therefore, we propose a fast and consistent variable selection method based on a generalized C-p criterion. The consistency of the method is provided by a high-dimensional asymptotic framework such that the sample size and the sum of the dimensions of response vectors and explanatory vectors divided by the sample size tend to infinity and some positive constant which are less than one, respectively. Through numerical simulations, it is shown that the proposed method has a high probability of selecting the true subset of explanatory variables and is fast under a moderate sample size even when the number of dimensions is large.
Recent studies have proposed several possibilities of combining K, Th and U airborne gamma-ray spectrometry channels to generate predictive algorithms maps. These algorithms can be used for mapping regolith in deeply ...
详细信息
Recent studies have proposed several possibilities of combining K, Th and U airborne gamma-ray spectrometry channels to generate predictive algorithms maps. These algorithms can be used for mapping regolith in deeply weathered terrains with residual, erosion, and deposition surfaces helping to developed strategies to better understand the regolith landscape and to improve geomorphology interpretation, and to identify mineral exploration target sites for primary (bedrock or saprolite) or supergene (hosted in lateritic duricrust) ore deposits. With the goal to easily map the regolith, two mathematical procedures were used on airborne gamma-ray spectrometry data in GIS software, validated by fieldwork on granite-greenstone belts in Midwest Brazil: 1. airborne gamma-ray spectrometry and altimetric data integrated in Boolean and fuzzy logic allowed segregating the areas with ferruginous and manganese residual lateritic duricrusts from erosional surface with rocks and saprolite with 90% of accuracy (kappa Boolean = 0.69 and kappa FAPO = 0.66) and 2. airborne gamma-ray spectrometry and altimetric data integrated with weathering stages in multivariate linear regression (basic statistic) helped establish the regional weathering intensity index, with acceptable error (r2 adjusted 0.6 and p-value < 5%). These two modeling techniques provide useful, accurate, rapidly and complementary regolith maps and can be applied in large regions for preliminary interpretations.
To improve the effectiveness of national image study on the "Belt and Road" countries in Central Asia, a national image study method based on the multivariatelinear is proposed in this paper. First, the nat...
详细信息
To improve the effectiveness of national image study on the "Belt and Road" countries in Central Asia, a national image study method based on the multivariatelinear is proposed in this paper. First, the national competitiveness database of International Institute for Management Development (IMD) and World Economic Forum is adopted to construct the evaluation index system of the "Belt and Road" countries;second, the multivariate linear regression analysis method is introduced to analyze the evaluation index system model of the "Belt and Road" countries mentioned above;third, the effectiveness of the proposed algorithm is verified through the simulation experiment. (C) 2018 Elsevier B.V. All rights reserved.
暂无评论