In this study, global solar radiation (GSR) was estimated based on 53 locations by using ELM, SVR, KNN, LR and NU-SVR methods. Methods were trained with a two-year data set and accuracy of the mentioned methods was tested with a one-year data set. The data set of each year was consisting of 12 months. Whereas the values of month, altitude, latitude, longitude, vapour pressure deficit and land surface temperature were used as input for developing models, GSR was obtained as output. Values of vapour pressure deficit and land surface temperature were taken from radiometry of NOAA-AVHRR satellite. Estimated solar radiation data were compared with actual data that were obtained from meteorological stations. According to statistical results, most successful method was NU-SVR method. The RMSE and MBE values of NU-SVR method were found to be 1,4972 MJ/m2 and 0,2652 MJ/m2, respectively. R value was 0,9728. Furthermore, worst prediction method was LR. For other methods, RMSE values were changing between 1,7746 MJ/m2 and 2,4546 MJ/m2. It can be seen from the statistical results that ELM, SVR, k-NN and NU-SVR methods can be used for estimation of GSR.
Climate model parameterizations of cumulus convection and other clouds that form due to small-scale turbulent eddies are a leading source of uncertainty in predicting the sensitivity of global warming to greenhouse gas increases. Even though we can write down equations governing the physics of cloud formation and fluid motion, these cloud-forming eddies are not resolved by the grid of a climate model, so the subgrid covariability of cloud processes and turbulence must be parameterized. Many approaches are used, all involving numerous subjective assumptions. Even when optimized to match present-day climate, these approaches produce a broad range of predictions about how clouds will change in a future climate.
High resolution models which explicitly simulate the clouds and turbulence on a very fine computational grid more realistically simulate cloud formation compared to observations. But it has proved challenging to translate this skill into better climate model parameterizations.
We will present one naturally stochastic approach for this using a computationally expensive approach called ‘superparameterization’ and then we will lay out a vision for how machine learning could be used to do this translation, which amounts to a form of stochastic coarse-graining. Developing the statistical and computational methods to realize this vision is a good challenge for this SAMSI year.
DEEP LEARNING BASED MULTIPLE REGRESSION TO PREDICT TOTAL COLUMN WATER VAPOR (...IJDKP
Total column water vapor is an important factor for the weather and climate. This study apply
deep learning based multiple regression to map the TCWV with elements that can improve
spatiotemporal prediction. In this study, we predict the TCWV with the use of ERA5 that is the
fifth generation ECMWF atmospheric reanalysis of the global climate. We use an appropriate
deep learning based multiple regression algorithm using Keras library to improve nonlinear
prediction between Total Column water vapor and predictors as Mean sea level pressure, Surface
pressure, Sea surface temperature, 100 metre U wind component, 100 metre V wind component,
10 metre U wind component, 10 metre V wind component, 2 metre dew point temperature, 2
metre temperature.
Nonlinear filtering approaches to field mapping by sampling using mobile sensorsijassn
This work proposes a novel application of existing powerful nonlinear filters, such as the standard
Extended Kalman Filter (EKF), some of its variants and the standard Unscented Kalman Filter (UKF), to
the estimation of a continuous spatio-temporal field that is spread over a wide area, and hence represented
by a large number of parameters when parameterized. We couple these filters with the powerful scheme of
adaptive sampling performed by a single mobile sensor, and investigate their performances with a view to
significantly improving the speed and accuracy of the overall field estimation. An extensive simulation work
was carried out to show that different variants of the standard EKF and the standard UKF can be used to
improve the accuracy of the field estimate. This paper also aims to provide some guideline for the user of
these filters in reaching a practical trade-off between the desired field estimation accuracy and the
required computational load.
Ill-posedness formulation of the emission source localization in the radio- d...Ahmed Ammar Rebai PhD
To contact the authors : tarek.salhi@gmail.com and ahmed.rebai2@gmail.com
In the field of radio detection in astroparticle physics, many studies have shown the strong dependence of the solution of the radio-transient sources localization problem (the radio-shower time of arrival on antennas) such solutions are purely numerical artifacts. Based on a detailed analysis of some already published results of radio-detection experiments like : CODALEMA 3 in France, AERA in Argentina and TREND in China, we demonstrate the ill-posed character of this problem in the sens of Hadamard. Two approaches have been used as the existence of solutions degeneration and the bad conditioning of the mathematical formulation problem. A comparison between experimental results and simulations have been made, to highlight the mathematical studies. Many properties of the non-linear least square function are discussed such as the configuration of the set of solutions and the bias.
Climate model parameterizations of cumulus convection and other clouds that form due to small-scale turbulent eddies are a leading source of uncertainty in predicting the sensitivity of global warming to greenhouse gas increases. Even though we can write down equations governing the physics of cloud formation and fluid motion, these cloud-forming eddies are not resolved by the grid of a climate model, so the subgrid covariability of cloud processes and turbulence must be parameterized. Many approaches are used, all involving numerous subjective assumptions. Even when optimized to match present-day climate, these approaches produce a broad range of predictions about how clouds will change in a future climate.
High resolution models which explicitly simulate the clouds and turbulence on a very fine computational grid more realistically simulate cloud formation compared to observations. But it has proved challenging to translate this skill into better climate model parameterizations.
We will present one naturally stochastic approach for this using a computationally expensive approach called ‘superparameterization’ and then we will lay out a vision for how machine learning could be used to do this translation, which amounts to a form of stochastic coarse-graining. Developing the statistical and computational methods to realize this vision is a good challenge for this SAMSI year.
DEEP LEARNING BASED MULTIPLE REGRESSION TO PREDICT TOTAL COLUMN WATER VAPOR (...IJDKP
Total column water vapor is an important factor for the weather and climate. This study apply
deep learning based multiple regression to map the TCWV with elements that can improve
spatiotemporal prediction. In this study, we predict the TCWV with the use of ERA5 that is the
fifth generation ECMWF atmospheric reanalysis of the global climate. We use an appropriate
deep learning based multiple regression algorithm using Keras library to improve nonlinear
prediction between Total Column water vapor and predictors as Mean sea level pressure, Surface
pressure, Sea surface temperature, 100 metre U wind component, 100 metre V wind component,
10 metre U wind component, 10 metre V wind component, 2 metre dew point temperature, 2
metre temperature.
Nonlinear filtering approaches to field mapping by sampling using mobile sensorsijassn
This work proposes a novel application of existing powerful nonlinear filters, such as the standard
Extended Kalman Filter (EKF), some of its variants and the standard Unscented Kalman Filter (UKF), to
the estimation of a continuous spatio-temporal field that is spread over a wide area, and hence represented
by a large number of parameters when parameterized. We couple these filters with the powerful scheme of
adaptive sampling performed by a single mobile sensor, and investigate their performances with a view to
significantly improving the speed and accuracy of the overall field estimation. An extensive simulation work
was carried out to show that different variants of the standard EKF and the standard UKF can be used to
improve the accuracy of the field estimate. This paper also aims to provide some guideline for the user of
these filters in reaching a practical trade-off between the desired field estimation accuracy and the
required computational load.
Ill-posedness formulation of the emission source localization in the radio- d...Ahmed Ammar Rebai PhD
To contact the authors : tarek.salhi@gmail.com and ahmed.rebai2@gmail.com
In the field of radio detection in astroparticle physics, many studies have shown the strong dependence of the solution of the radio-transient sources localization problem (the radio-shower time of arrival on antennas) such solutions are purely numerical artifacts. Based on a detailed analysis of some already published results of radio-detection experiments like : CODALEMA 3 in France, AERA in Argentina and TREND in China, we demonstrate the ill-posed character of this problem in the sens of Hadamard. Two approaches have been used as the existence of solutions degeneration and the bad conditioning of the mathematical formulation problem. A comparison between experimental results and simulations have been made, to highlight the mathematical studies. Many properties of the non-linear least square function are discussed such as the configuration of the set of solutions and the bias.
Performed analysis on Temperature, Wind Speed, Humidity and Pressure data-sets and implemented decision tree & clustering to predict possibility of rain
Created graphs and plots using algorithms such as k-nearest neighbors, naïve bayes, decision tree and k means clustering
Determination of wind energy potential of campus area of siirt universitymehmet şahin
In this study, wind energy potential of Siirt
University campus area is statistically examined by using the mean hourly wind speed data between 2014
and 2015 years which are measured by Vantage Pro2 device, located at the roof of the Engineering Faculty building with 6 m altitude. Weibull distribution
function and Rayleigh distribution function are used
as statistical approach to evaluate the wind data. Weibull distribution function is examined by using two different methods that are maximum likelihood estimation and Rayleigh method. The determination
coefficient (R2) and Root Mean Square Error (RMSE) values of these methods are compared. According the error analysis, it is indicated that the Rayleigh method
gives better results. Wind speed and wind power density are calculated in pursuance of Weibull distribution parameters. The results are evaluated as
monthly and annually. Hence, this preliminary study is made to determine the wind energy potential of Siirt University campus area.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Supervised machine learning based dynamic estimation of bulk soil moisture us...eSAT Journals
Abstract In this paper artificial neural network based sensor informatics architecture has been investigated; including proposed continuous daily estimation of area wise surface soil moisture using cosmic ray sensor’s neutron count time series. Study was conducted based on cosmic ray data available from two Australian locations. The main focus of this study was to develop a data driven approach to convert neutron counts into area wise ground surface soil moisture estimates. Independent surface soil moisture data from the Australian Water Availability Project (AWAP) was used as ground truth. A comparative study using five different types of neural networks, namely, Feed Forward Back Propagation (FFBPN), Multi-Layer Perceptron (MLPN), Radial Basis Function (RBFN), Elman (EN), and Probabilistic networks (PNN) was conducted to evaluate the overall soil moisture estimation accuracy. Best performance from the Elman network outperformed all other neural networks with 94% accuracy with 92% sensitivity and 97% specificity based on Tullochgorum data. Overall high accuracy proved the effectiveness of the Elman neural network to estimate surface soil moisture continuously using cosmic ray sensors. Index Terms: Artificial Neural Network, Surface Soil Moisture, Cosmic Ray Sensors, Neutron Counts.
Physical processes in the earth system are modeled with mathematical representations called parameterizations. This talk will describe some of the conceptual approaches and mathematics used do describe physical parameterizations focusing on cloud parameterizations. This includes tracing physical laws to discrete representations in coarse scale models. Clouds illustrate several of the complexities and techniques common to many physical parameterizations. This includes the problem of different scales, sub-grid scale variability. Discussions of mathematical methods for dealing with the sub-grid scale will be discussed. In-exactness or indeterminate problems for both weather and climate will be discussed, including the problems of indeterminate parameterizations, and inexact initial conditions. Different mathematical methods, including the use of stochastic methods, will be described and discussed, with examples from contemporary earth system models.
Using statistical and machine learning techniques to forecast the PV solar power, which can be implemented for: • Managing the economic dispatch, unit commitment, and trading of PV solar power generations with other conventional generations; • Using with situational awareness tools to manage the ramp limitation; Optimal energy management of energy storage systems; • Voltage regulator settings on feeders with PV distributed generation.
The melting of the West Antarctic ice sheet (WAIS) is likely to cause a significant rise in sea levels. Studying the present state of WAIS and predicting its future behavior involves the use of computer models of ice sheet dynamics as well as observational data. I will outline general statistical challenges posed by these scientific questions and data sets.
This discussion is based on joint work with Yawen Guan (Penn State/SAMSI), Won Chang (U. of Cincinnati), Patrick Applegate, David Pollard (Penn State)
Extreme weather events pose great potential risk on ecosystem, infrastructure and human health. Analyzing extreme weather in the observed record (satellite, reanalysis products) and characterizing changes in extremes in simulations of future climate regimes is an important task. Thus far, extreme weather events have been typically specified by the community through hand-coded, multi-variate threshold conditions. Such criteria are usually subjective, and often there is little agreement in the community on the specific algorithm that should be used. We propose the use of a different approach: machine learning (and in particular deep learning) for solving this important problem. If human experts can provide spatio-temporal patches of a climate dataset, and associated labels, we can turn to a machine learning system to learn the underlying feature representation. The trained Machine Learning (ML) system can then be applied to novel datasets, thereby automating the pattern detection step. Summary statistics, such as location, intensity and frequency of such events can be easily computed as a post-process.
We will report compelling results from our investigations of Deep Learning for the tasks of classifying tropical cyclones, atmospheric rivers and weather front events. For all of these events, we observe 90-99% classification accuracy. We will also report on progress in localizing such events: namely drawing a bounding box (of the correct size and scale) around the weather pattern of interest. Both tasks currently utilize multi-layer convolutional networks in conjunction with hyper-parameter optimization. We utilize HPC systems at NERSC to perform the optimization across multiple nodes, and utilize highly-tuned libraries to utilize multiple cores on a single node. We will conclude with thoughts on the frontier of Deep Learning and the role of humans (vis-a-vis AI) in the scientific discovery process.
Calculation of solar radiation by using regression methodsmehmet şahin
Abstract. In this study, solar radiation was estimated at 53 location over Turkey with
varying climatic conditions using the Linear, Ridge, Lasso, Smoother, Partial least, KNN
and Gaussian process regression methods. The data of 2002 and 2003 years were used to
obtain regression coefficients of relevant methods. The coefficients were obtained based on
the input parameters. Input parameters were month, altitude, latitude, longitude and landsurface
temperature (LST).The values for LST were obtained from the data of the National
Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer
(NOAA-AVHRR) satellite. Solar radiation was calculated using obtained coefficients in
regression methods for 2004 year. The results were compared statistically. The most
successful method was Gaussian process regression method. The most unsuccessful method
was lasso regression method. While means bias error (MBE) value of Gaussian process
regression method was 0,274 MJ/m2, root mean square error (RMSE) value of method was
calculated as 2,260 MJ/m2. The correlation coefficient of related method was calculated as
0,941. Statistical results are consistent with the literature. Used the Gaussian process
regression method is recommended for other studies.
Short-term load forecasting with using multiple linear regression IJECEIAES
In this paper short term load forecasting (STLF) is done with using multiple linear regression (MLR). A day ahead load forecasting is obtained in this paper. Regression coefficients were found out with the help of method of least square estimation. Load in electrical power system is dependent on temperature, due point and seasons and also load has correlation to the previous load consumption (Historical data). So the input variables are temperature, due point, load of prior day, hours, and load of prior week. To validate the model or check the accuracy of the model mean absolute percentage error is used and R squared is checked which is shown in result section. Using day ahead forecasted data weekly forecast is also obtained.
Prediction of Extreme Wind Speed Using Artificial Neural Network ApproachScientific Review SR
Prediction of an accurate wind speed of wind farms is necessary because of the intermittent nature
of wind for any region. Number of methods such as persistence, physical, statistical, spatial correlation, artificial
intelligence network and hybrid are generally available for prediction of wind speed. In this paper, ANN based
methods viz., Multi Layer Perceptron (MLP) and Radial Basis Function (RBF) neural networks are used. The
performance of the networks applied for prediction of wind speed is evaluated by model performance indicators
viz., Correlation Coefficient (CC), Model Efficiency (MEF) and Mean Absolute Percentage Error (MAPE).
Meteorological parameters such as maximum and minimum temperature, air pressure, solar radiation and
altitude are considered as input units for MLP and RBF networks to predict the extreme wind speed at Delhi.
The study shows the values of CC, MEF and MAPE between the observed and predicted wind speed (using
MLP) are computed as 0.992, 95.4% and 4.3% respectively while training the network data. For RBF network,
the values of CC, MEF and MAPE are computed as 0.992, 95.9% and 3.0% respectively. The model
performance analysis indicates the RBF is better suited network among two different networks studied for
prediction of extreme wind speed at Delhi.
The accurate prediction of solar irradiation has been
a leading problem for better energy scheduling approach.
Hence in this paper, an Artificial neural network based solar
irradiance is proposed for five days duration the data is
obtained from National Renewable Energy Laboratory, USA
and the simulation were performed using MATLAB 2013. It
was found that the neural model was able to predict the solar
irradiance with a mean square error of 0.0355.
Dear Student,
DREAMWEB TECHNO SOLUTIONS is one of the Hardware Training and Software Development centre available in
Trichy. Pioneer in corporate training, DREAMWEB TECHNO SOLUTIONS provides training in all software
development and IT-related courses, such as Embedded Systems, VLSI, MATLAB, JAVA, J2EE, CIVIL,
Power Electronics, and Power Systems. It’s certified and experienced faculty members have the
competence to train students, provide consultancy to organizations, and develop strategic
solutions for clients by integrating existing and emerging technologies.
ADD: No:73/5, 3rd Floor, Sri Kamatchi Complex, Opp City Hospital, Salai Road, Trichy-18
Contact @ 7200021403/04
phone: 0431-4050403
Expert system design for elastic scattering neutrons optical model using bpnnijcsa
In present paper, a proposed expert system is designed to obtain a trained formulae for the optical model
parameters used in elastic scattering neutrons of light nuclei for (7Li), at energy range between [(1) to
(20)] MeV. A simple algorithm has used to design this expert system, while a multi-layer backwardpropagation
neural network (BPNN) is applied for training and testing the data used in this model. This
group of formulae may get a simple expert system occurring from governing formulae model, and predicts
the critical parameters usually resulted from the complicated computer coding methods. This expert system
may use in nuclear reactions yields in both fission and fusion nature who gives more closely results to the
real model.
Performed analysis on Temperature, Wind Speed, Humidity and Pressure data-sets and implemented decision tree & clustering to predict possibility of rain
Created graphs and plots using algorithms such as k-nearest neighbors, naïve bayes, decision tree and k means clustering
Determination of wind energy potential of campus area of siirt universitymehmet şahin
In this study, wind energy potential of Siirt
University campus area is statistically examined by using the mean hourly wind speed data between 2014
and 2015 years which are measured by Vantage Pro2 device, located at the roof of the Engineering Faculty building with 6 m altitude. Weibull distribution
function and Rayleigh distribution function are used
as statistical approach to evaluate the wind data. Weibull distribution function is examined by using two different methods that are maximum likelihood estimation and Rayleigh method. The determination
coefficient (R2) and Root Mean Square Error (RMSE) values of these methods are compared. According the error analysis, it is indicated that the Rayleigh method
gives better results. Wind speed and wind power density are calculated in pursuance of Weibull distribution parameters. The results are evaluated as
monthly and annually. Hence, this preliminary study is made to determine the wind energy potential of Siirt University campus area.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Supervised machine learning based dynamic estimation of bulk soil moisture us...eSAT Journals
Abstract In this paper artificial neural network based sensor informatics architecture has been investigated; including proposed continuous daily estimation of area wise surface soil moisture using cosmic ray sensor’s neutron count time series. Study was conducted based on cosmic ray data available from two Australian locations. The main focus of this study was to develop a data driven approach to convert neutron counts into area wise ground surface soil moisture estimates. Independent surface soil moisture data from the Australian Water Availability Project (AWAP) was used as ground truth. A comparative study using five different types of neural networks, namely, Feed Forward Back Propagation (FFBPN), Multi-Layer Perceptron (MLPN), Radial Basis Function (RBFN), Elman (EN), and Probabilistic networks (PNN) was conducted to evaluate the overall soil moisture estimation accuracy. Best performance from the Elman network outperformed all other neural networks with 94% accuracy with 92% sensitivity and 97% specificity based on Tullochgorum data. Overall high accuracy proved the effectiveness of the Elman neural network to estimate surface soil moisture continuously using cosmic ray sensors. Index Terms: Artificial Neural Network, Surface Soil Moisture, Cosmic Ray Sensors, Neutron Counts.
Physical processes in the earth system are modeled with mathematical representations called parameterizations. This talk will describe some of the conceptual approaches and mathematics used do describe physical parameterizations focusing on cloud parameterizations. This includes tracing physical laws to discrete representations in coarse scale models. Clouds illustrate several of the complexities and techniques common to many physical parameterizations. This includes the problem of different scales, sub-grid scale variability. Discussions of mathematical methods for dealing with the sub-grid scale will be discussed. In-exactness or indeterminate problems for both weather and climate will be discussed, including the problems of indeterminate parameterizations, and inexact initial conditions. Different mathematical methods, including the use of stochastic methods, will be described and discussed, with examples from contemporary earth system models.
Using statistical and machine learning techniques to forecast the PV solar power, which can be implemented for: • Managing the economic dispatch, unit commitment, and trading of PV solar power generations with other conventional generations; • Using with situational awareness tools to manage the ramp limitation; Optimal energy management of energy storage systems; • Voltage regulator settings on feeders with PV distributed generation.
The melting of the West Antarctic ice sheet (WAIS) is likely to cause a significant rise in sea levels. Studying the present state of WAIS and predicting its future behavior involves the use of computer models of ice sheet dynamics as well as observational data. I will outline general statistical challenges posed by these scientific questions and data sets.
This discussion is based on joint work with Yawen Guan (Penn State/SAMSI), Won Chang (U. of Cincinnati), Patrick Applegate, David Pollard (Penn State)
Extreme weather events pose great potential risk on ecosystem, infrastructure and human health. Analyzing extreme weather in the observed record (satellite, reanalysis products) and characterizing changes in extremes in simulations of future climate regimes is an important task. Thus far, extreme weather events have been typically specified by the community through hand-coded, multi-variate threshold conditions. Such criteria are usually subjective, and often there is little agreement in the community on the specific algorithm that should be used. We propose the use of a different approach: machine learning (and in particular deep learning) for solving this important problem. If human experts can provide spatio-temporal patches of a climate dataset, and associated labels, we can turn to a machine learning system to learn the underlying feature representation. The trained Machine Learning (ML) system can then be applied to novel datasets, thereby automating the pattern detection step. Summary statistics, such as location, intensity and frequency of such events can be easily computed as a post-process.
We will report compelling results from our investigations of Deep Learning for the tasks of classifying tropical cyclones, atmospheric rivers and weather front events. For all of these events, we observe 90-99% classification accuracy. We will also report on progress in localizing such events: namely drawing a bounding box (of the correct size and scale) around the weather pattern of interest. Both tasks currently utilize multi-layer convolutional networks in conjunction with hyper-parameter optimization. We utilize HPC systems at NERSC to perform the optimization across multiple nodes, and utilize highly-tuned libraries to utilize multiple cores on a single node. We will conclude with thoughts on the frontier of Deep Learning and the role of humans (vis-a-vis AI) in the scientific discovery process.
Calculation of solar radiation by using regression methodsmehmet şahin
Abstract. In this study, solar radiation was estimated at 53 location over Turkey with
varying climatic conditions using the Linear, Ridge, Lasso, Smoother, Partial least, KNN
and Gaussian process regression methods. The data of 2002 and 2003 years were used to
obtain regression coefficients of relevant methods. The coefficients were obtained based on
the input parameters. Input parameters were month, altitude, latitude, longitude and landsurface
temperature (LST).The values for LST were obtained from the data of the National
Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer
(NOAA-AVHRR) satellite. Solar radiation was calculated using obtained coefficients in
regression methods for 2004 year. The results were compared statistically. The most
successful method was Gaussian process regression method. The most unsuccessful method
was lasso regression method. While means bias error (MBE) value of Gaussian process
regression method was 0,274 MJ/m2, root mean square error (RMSE) value of method was
calculated as 2,260 MJ/m2. The correlation coefficient of related method was calculated as
0,941. Statistical results are consistent with the literature. Used the Gaussian process
regression method is recommended for other studies.
Short-term load forecasting with using multiple linear regression IJECEIAES
In this paper short term load forecasting (STLF) is done with using multiple linear regression (MLR). A day ahead load forecasting is obtained in this paper. Regression coefficients were found out with the help of method of least square estimation. Load in electrical power system is dependent on temperature, due point and seasons and also load has correlation to the previous load consumption (Historical data). So the input variables are temperature, due point, load of prior day, hours, and load of prior week. To validate the model or check the accuracy of the model mean absolute percentage error is used and R squared is checked which is shown in result section. Using day ahead forecasted data weekly forecast is also obtained.
Prediction of Extreme Wind Speed Using Artificial Neural Network ApproachScientific Review SR
Prediction of an accurate wind speed of wind farms is necessary because of the intermittent nature
of wind for any region. Number of methods such as persistence, physical, statistical, spatial correlation, artificial
intelligence network and hybrid are generally available for prediction of wind speed. In this paper, ANN based
methods viz., Multi Layer Perceptron (MLP) and Radial Basis Function (RBF) neural networks are used. The
performance of the networks applied for prediction of wind speed is evaluated by model performance indicators
viz., Correlation Coefficient (CC), Model Efficiency (MEF) and Mean Absolute Percentage Error (MAPE).
Meteorological parameters such as maximum and minimum temperature, air pressure, solar radiation and
altitude are considered as input units for MLP and RBF networks to predict the extreme wind speed at Delhi.
The study shows the values of CC, MEF and MAPE between the observed and predicted wind speed (using
MLP) are computed as 0.992, 95.4% and 4.3% respectively while training the network data. For RBF network,
the values of CC, MEF and MAPE are computed as 0.992, 95.9% and 3.0% respectively. The model
performance analysis indicates the RBF is better suited network among two different networks studied for
prediction of extreme wind speed at Delhi.
The accurate prediction of solar irradiation has been
a leading problem for better energy scheduling approach.
Hence in this paper, an Artificial neural network based solar
irradiance is proposed for five days duration the data is
obtained from National Renewable Energy Laboratory, USA
and the simulation were performed using MATLAB 2013. It
was found that the neural model was able to predict the solar
irradiance with a mean square error of 0.0355.
Dear Student,
DREAMWEB TECHNO SOLUTIONS is one of the Hardware Training and Software Development centre available in
Trichy. Pioneer in corporate training, DREAMWEB TECHNO SOLUTIONS provides training in all software
development and IT-related courses, such as Embedded Systems, VLSI, MATLAB, JAVA, J2EE, CIVIL,
Power Electronics, and Power Systems. It’s certified and experienced faculty members have the
competence to train students, provide consultancy to organizations, and develop strategic
solutions for clients by integrating existing and emerging technologies.
ADD: No:73/5, 3rd Floor, Sri Kamatchi Complex, Opp City Hospital, Salai Road, Trichy-18
Contact @ 7200021403/04
phone: 0431-4050403
Expert system design for elastic scattering neutrons optical model using bpnnijcsa
In present paper, a proposed expert system is designed to obtain a trained formulae for the optical model
parameters used in elastic scattering neutrons of light nuclei for (7Li), at energy range between [(1) to
(20)] MeV. A simple algorithm has used to design this expert system, while a multi-layer backwardpropagation
neural network (BPNN) is applied for training and testing the data used in this model. This
group of formulae may get a simple expert system occurring from governing formulae model, and predicts
the critical parameters usually resulted from the complicated computer coding methods. This expert system
may use in nuclear reactions yields in both fission and fusion nature who gives more closely results to the
real model.
Elements Space and Amplitude Perturbation Using Genetic Algorithm for Antenna...CSCJournals
A simple and fast genetic algorithm (GA) developed to reduce the sidelobes in non-uniformly spaced linear antenna arrays. The proposed GA algorithm optimizes two vectors of variables to increase the Main lobe to Sidelobe power ratio (M/S) of array’s radiation pattern. The algorithm, in the first phase calculates the positions of the array elements and in the second phase, it manipulates the amplitude of excitation signals for each element. The simulations performed for 16 and 24 elements array structure. The results indicated that M/S improved in first phase from 13.2 to over 22.2dB meanwhile the half power beamwidth (HPBW) left almost unchanged. After element replacement, in the second phase, by using amplitude tapering further improvement up to 32dB was achieved. Also, the simulations shown that after element space perturbation, some antenna elements can be merged together without any performance degradation in radiation pattern in terms of gain and sidelobes level.
Relevance Vector Machines for Earthquake Response Spectra drboon
This study uses Relevance Vector Machine (RVM) regression to develop a probabilistic model for the average horizontal component of 5%-damped earthquake response spectra. Unlike conventional models, the proposed approach does not require a functional form, and constructs the model based on a set predictive variables and a set of representative ground motion records. The RVM uses Bayesian inference to determine the confidence intervals, instead of estimating them from the mean squared errors on the training set. An example application using three predictive variables (magnitude, distance and fault mechanism) is presented for sites with shear wave velocities ranging from 450 m/s to 900 m/s. The predictions from the proposed model are compared to an existing parametric model. The results demonstrate the validity of the proposed model, and suggest that it can be used as an alternative to the conventional ground motion models. Future studies will investigate the effect of additional predictive variables on the predictive performance of the model.
Relevance Vector Machines for Earthquake Response Spectra drboon
This study uses Relevance Vector Machine (RVM) regression to develop a probabilistic model for the average horizontal component of 5%-damped earthquake response spectra. Unlike conventional models, the proposed approach does not require a functional form, and constructs the model based on a set predictive variables and a set of representative ground motion records. The RVM uses Bayesian inference to determine the confidence intervals, instead of estimating them from the mean squared errors on the training set. An example application using three predictive variables (magnitude, distance and fault mechanism) is presented for sites with shear wave velocities ranging from 450 m/s to 900 m/s. The predictions from the proposed model are compared to an existing parametric model. The results demonstrate the validity of the proposed model, and suggest that it can be used as an alternative to the conventional ground motion models. Future studies will investigate the effect of additional predictive variables on the predictive performance of the model.
Comparitive analysis of doa and beamforming algorithms for smart antenna systemseSAT Journals
Abstract This paper revolves around the implementation of Direction of arrival and Adaptive beam-forming algorithms for Smart Antenna Systems. This paper also investigates the implementation of algorithms on various planner array geometries viz. circular and rectangular. Music algorithm is primarily finds the possible location of desired user and adaptive beam-forming algorithms such as LMS, RLS and CMA algorithms adapts the weights of the array. DOA estimation gives the maximum peak of spectrum with respect to angle of arrival where the desired user is supposed to exist. After DOA estimation weights of array antenna are changed with the changing received signal. This methodology is called as Spectral estimation, which allows the antenna pattern to steer in desired direction estimated by DOA and simultaneously null out the interfering signals. Rate of convergence is the major criterion for comparison for adaptive beam-forming algorithms. Keywords: DOA, MUSIC, LMS, RLS, CMA, SAS.
Optimal artificial neural network configurations for hourly solar irradiation...IJECEIAES
Solar energy is widely used in order to generate clean electric energy. However, due to its intermittent nature, this resource is only inserted in a limited way within the electrical networks. To increase the share of solar energy in the energy balance and allow better management of its production, it is necessary to know precisely the available solar potential at a fine time step to take into account all these stochastic variations. In this paper, a comparison between different artificial neural network (ANN) configurations is elaborated to estimate the hourly solar irradiation. An investigation of the optimal neurons and layers is investigated. To this end, feedforward neural network, cascade forward neural network and fitting neural network have been applied for this purpose. In this context, we have used different meteorological parameters to estimate the hourly global solar irirradiation in the region of Laghouat, Algeria. The validation process shows that choosing the cascade forward neural network two inputs gives an R2 value equal to 97.24% and an normalized root mean square error (NRMSE) equals to 0.1678 compared to the results of three inputs, which gives an R2 value equaled to 95.54% and an NRMSE equals to 0.2252. The comparison between different existing methods in literature show the goodness of the proposed models.
MODELING THE CHLOROPHYLL-A FROM SEA SURFACE REFLECTANCE IN WEST AFRICA BY DEE...gerogepatton
Deep learning provide successful applications in many fields. Recently, machines learning are involved for oceans remote sensing applications. In this study, we use and compare about eight (8) deep learning estimators for retrieval of a mainly pigment of phytoplankton. Depending on the water case and the multiple instruments simultaneously observing the earth on a variety of platforms, several algorithm are used to estimate the chlolophyll-a from marine reflectance.By using a long-term multi-sensor time-series of satellite ocean-colour data, as MODIS, SeaWifs, VIIRS, MERIS, etc…, we make a unique deep network model able to establish a relationship between sea surface reflectance and chlorophyll-a from any measurement satellite sensor over West Africa. These data fusion take into account the bias between case water and instruments.We construct several chlorophyll-a concentration prediction deep learning based models, compare them and therefore use the best for our study. Results obtained for accuracy training and test are quite good. The mean absolute error are very low and vary between 0,07 to 0,13 mg/m
Similar to Estimation of global solar radiation by using machine learning methods (20)
Yapay sinir ağı ve noaaavhrr uydu verilerini kullanarak hava sıcaklığının tah...mehmet şahin
iklim değişikliği, çeşitli ısı ve radyasyon akılarının belirlenmesinde, buhar basınç açığı, su potansiyeli, kentsel arazi kullanımı
ve ısı adası, kısa dalga ve uzun dalga radyasyon, stoma direnci, ekoloji, hidroloji ve atmosfer bilimleri de dahil olmak üzere bir
çok uygulama için kullanılmaktadır. Ayrıca, hava sıcaklığı bilgisi insan sağlığı için gereklidir. Bu kadar önemli olan hava
sıcaklığı, meteorolojik istasyonlarda ölçülmektedir. Fakat istasyon dağılımları yeryüzünde yeterli düzeyde olmadığı gibi yeterli
sayıda istasyon da bulunmamaktadır. Bu nedenle, uydular kullanılmaya başlanmıştır. Literatürde yer yüzey sıcaklığı tahmini
yapmak için oldukça fazla algoritma geliştirilmesine rağmen doğrudan hava sıcaklığını tahmin eden algoritmalar yeterince
geliştirilememiştir. Bu nedenle bu çalışmada yapay sinir ağı kullanılarak hava sıcaklığı tahmini yapılmıştır. Yapay sinir ağda
ay, yükseklik, enlem, boylam, aylık ortalama yer yüzey sıcaklıkları girdi olarak kullanılırken, aylık ortalama hava sıcaklığı çıktı
olarak elde edilmiştir. Girdi parametrelerinden yer yüzey sıcaklığı, NOAA/AVHRR datalarından sağlanmıştır. Ağda öğrenme
algoritmaları olarak; tarinlm, trainscg, trainoss kullanılırken transfer fonksiyonu olarak tansig, logsig ve lineer kullanılmıştır.
Ocak 1995’den Aralık 2005’e kadar olarak zaman aralığı, çalışma periyodu olarak belirlenmiştir. Ağın eğitilmesi için 1995-
2004 yılları arası veriler kullanılırken, test verisi olarak 2005 yılı verileri kullanılmıştır. Tahmin sonuçlarının, gerçek datalarla
istatistiksel olarak değerlendirilmesi yapılmış olup hata değeri oldukça az çıkmıştır. El edilen en iyi modellemede, korelasyon
katsayısı ve kök ortalama kare hatası sırasıyla 0.996 ve 1.253 K olarak hesaplanmıştır.
Siirt ilinin yer yüzey sıcaklığının belirlenmesi için farklı split window alg...mehmet şahin
Land surface temperature is an important parameter to control the energy exchange between earth's surface and atmosphere.
In addition, land surface temperature is used in the development of computer modelling of many environmental quantity as
climate change, numerical weather prediction, global water cycle, drought index, solar radiation and frost. In this study,
visible and near infrared channels (channels 1 and 2) and thermal channels (channels 4 and 5) of NOAA / AVHRR satellite
images were used to obtain land surface temperature data. Price-1984, Becker and Li–1990 and Ulivieri et al.-1994 algorithms
were determined to calculate the land surface temperature. Results of land surface temperature obtained from satellite
algorithms were compared in terms of statistics based on the location of Siirt with the actual land surface temperatures
obtained from General Directorate of Meteorology. According to the results; Root Mean Square Error values of Price-1984,
Becker and Li-1990, and Ulivieri et al.-1994 algorithms were calculated as 3.308K, 2.681K and 2.171K, respectively. In the
same order, the correlation coefficients of algorithms were obtained as 0.972, 0974 and 0984. It has been reached to
conclude that using Ulivieri et al.-1994 algorithm is appropriate to estimate land surface temperature that has been obtained
from Ulivieri et al.-1994 algorithm for getting with the lowest error in satellite-based solar energy calculations.
Forecasting of air temperature based on remotemehmet şahin
The aim of this research is to forecast air temperature based on remote sensing data. So, land surface
temperature and air temperature values which were measured by Republic of Turkey Ministry of Forestry and
Water Affairs (Turkish State Meteorological Service) during the period 1995–2001 at seven stations (Adana,
Ankara, Balıkesir, Đzmir, Samsun, Sanlıurfa, Van) were compared. The monthly land surface temperature and
air temperature were used to have correlation coefficients over Turkey. An empirical method was obtained from
equation of correlation coefficients. Separately, Price algorithm was used for the estimation of land surface
temperature values to get air temperatures. Then as statistical, air temperature values, belongs to meteorological
data in Turkey (26–45ºE and 36–42ºN) throughout 2002, were evaluated. The research results showed that
accuracy of estimation of the air temperature changes from 2.453ºK to 2.825ºK by root mean square error.
Estimation of wind power density with artificial neural networkmehmet şahin
Industry and technology are rapidly developing with each passing day. They need energy to sustain this evolution. The demand of energy is mainly provided from fossil fuels. Unfortunately, this kind of energy reserves are consumed away day by day. Therefore, there is a need to use alternative energy sources to supply energy needs. Alternative energy sources can be listed as; solar, wind, wave, biomass, geothermal and hydro-electric power. Our country has significant potential for wind energy. Wind power density estimation is required to determine the wind potential. In this study, the wind power density was estimated by using artificial neural network (ANN) method. Forty meteorological stations were used for ANN training, while eighteen meteorological stations were used to test the trained network. Network has trained according to, respectively; trainlm, trainbfg, trainscg, traincgp traincgb, traincgf ve trainoss learning algorithms. The correlation coefficient (R) and Mean bias error (MBE) of the best developed model were calculated as 0,9767 and -0,3124 W/m2 respectively. Root Mean Square Error (RMSE) was calculated as 1,4786 W/m2. In conclusion, the obtained results demonstrate that the developed model can be used to estimate the wind power density.
Estimation of solar radiation by different machine learning methodsmehmet şahin
In this study, solar radiation was estimated depend on 34 locations. While doing distribution
of the locations on Turkey, they were taken into consideration to be different climatic
conditions. In the study, meteorological data was used between the years of 2007 and 2015. The
meteorological data which were used, were land surface temperature at 5 cm, air temperature,
sunshine duration and solar radiation. As geographical data, locations of latitude, longitude
and altitude were used. Three different methods were used for estimating the solar radiation.
These are the methods of multilayer perceptron neural network, multiple regression and radial
basis function network. The estimation results obtained from the methods were compared with
the actual values obtained from the meteorological station, statistically. The mean bias error
(MBE), root mean square error (RMSE) and correlation coefficient (R) were used as evaluation
criteria. According to statistical results, multilayer perceptron neural networks has given the
most successful result in the three methods. The MBE, RMSE and R values of method were
calculated as 1.5321 MJ/m2, 2.4295 MJ/m2, and 0.9428, respectively. It is recommended to
researchers to use multilayer perceptron neural networks method for studies in this area.
Forecasting long term global solar radiation with an ann algorithmmehmet şahin
and energy-efficient buildings, solar concentrators, photovoltaic-systems and a site-selection of sites for future
power plants). To establish long-term sustainability of solar energy, energy practitioners utilize versatile
predictive models of G as an indispensable decision-making tool. Notwithstanding this, sparsity of solar sites,
instrument maintenance, policy and fiscal issues constraint the availability of model input data that must be
used for forecasting the onsite value of G. To surmount these challenge, low-cost, readily-available satellite
products accessible over large spatial domains can provide viable alternatives. In this paper, the preciseness of
artificial neural network (ANN) for predictive modelling of G is evaluated for regional Queensland, which
employed Moderate Resolution Imaging Spectroradiometer (MODIS) land-surface temperature (LST) as an
effective predictor. To couple an ANN model with satellite-derived variable, the LST data over 2012–2014 are
acquired in seven groups, with three sites per group where the data for first two (2012–2013) are utilised for
model development and the third (2014) group for cross-validation. For monthly horizon, the ANN model is
optimized by trialing 55 neuronal architectures, while for seasonal forecasting, nine neuronal architectures are
trailed with time-lagged LST. ANN coupled with zero lagged LST utilised scaled conjugate gradient algorithm,
and while ANN with time-lagged LST utilised Levenberg-Marquardt algorithm. To ascertain conclusive results,
the objective model is evaluated via multiple linear regression (MLR) and autoregressive integrated moving
average (ARIMA) algorithms. Results showed that an ANN model outperformed MLR and ARIMA models
where an analysis yielded 39% of cumulative errors in smallest magnitude bracket, whereas MLR and ARIMA
produced 15% and 25%. Superiority of an ANN model was demonstrated by site-averaged (monthly) relative
error of 5.85% compared with 10.23% (MLR) and 9.60 (ARIMA) with Willmott's Index of 0.954 (ANN), 0.899
(MLR) and 0.848 (ARIMA). This work ascertains that an ANN model coupled with satellite-derived LST data
can be adopted as a qualified stratagem for the proliferation of solar energy applications in locations that have
an appropriate satellite footprint.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Estimation of global solar radiation by using machine learning methods
1. International Journal of Thales Engineering Sciences (JTHES)
ISSN (print): 2149-5173
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Estimation of Global Solar Radiation by Using Machine Learning
Methods
Mehmet Bolat
Engineering Faculty/Siirt University
Mehmet Şahin
Engineering Faculty/Siirt University
ABSTRACT
In this study, global solar radiation (GSR) was estimated based on 53 locations by using ELM, SVR,
KNN, LR and NU-SVR methods. Methods were trained with a two-year data set and accuracy of the
mentioned methods was tested with a one-year data set. The data set of each year was consisting of 12
months. Whereas the values of month, altitude, latitude, longitude, vapour pressure deficit and land surface
temperature were used as input for developing models, GSR was obtained as output. Values of vapour
pressure deficit and land surface temperature were taken from radiometry of NOAA-AVHRR satellite.
Estimated solar radiation data were compared with actual data that were obtained from meteorological
stations. According to statistical results, most successful method was NU-SVR method. The RMSE and
MBE values of NU-SVR method were found to be 1,4972 MJ/m2
and 0,2652 MJ/m2
, respectively. R value
was 0,9728. Furthermore, worst prediction method was LR. For other methods, RMSE values were
changing between 1,7746 MJ/m2
and 2,4546 MJ/m2
. It can be seen from the statistical results that ELM,
SVR, k-NN and NU-SVR methods can be used for estimation of GSR.
Keywords: Global Solar Radiation, NU-SVR
1 INTRODUCTION
The world has abundant solar energy resources. So that we need essentially to search sources of
energy. Nowadays, climate change is increasing effects on human life. It shows us; why we must work
more and more about this. One of them is GSR that is measured by a pyranometer but its installation is a
very costly, takes long time and unusual way, especially in the developing countries. As mentioned,
meteorological data based on many various factor and for each point, it cannot be measure easily. Cause of
all these reason, it is modeled by some methods and it is estimated by this models. Estimation of daily GSR
by the sunshine based models (Linear, Quadratic and Cubic) has been made and compared. The comparison
results showed that the cubic model is equivalent to the quadratic model and the most constructive statistical
results are given by the quadratic model [1]. Clearness index-beam transmittance numerical correlation was
proposed using measured ambient temperature and relative humidity data to estimate hourly solar radiation
[2]. Many researchers developed the correlations to predict the mean monthly diffuse solar radiation.
However, most of these are based on regression analyses which are limited in accuracy and the number of
parameters they can handle effectively [3,4]. The major drawback of the linear regression models is that
they will underachieve when used to model nonlinear systems. The time series models like moving average,
exponential smoothing and decomposition models are proposed for short term prediction of solar irradiance.
2. International Journal of Thales Engineering Sciences (JTHES)
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Many statistical and machine learning techniques have been used to forecast solar irradiance,
including Autoregressive Moving Average (ARMA), Autoregressive Integrated Moving Average
(ARIMA), Coupled Autoregressive and Dynamical System (CARDS), Artificial Neural Network (ANN),
k-Nearest Neighbor (kNN), and Support Vector Regression (SVR), Extreme Learning Machines (ELM),
linear regression (LR) [5]. In this study, the satellite based models and methods which are developed by
combining a current statistical model with data obtained from satellite data is used. We profit by satellites.
Because satellites; in very large areas, with short intervals, is able to scan in different phases of
electromagnetic spectrum [6]. We used ELM, SVR, k-NN, LR and NU-SVR as estimating methods. The
values of month, altitude, latitude, longitude, vapour pressure deficit and land surface temperature were
used as input for developing models, GSR was taken as output. Land surface temperature and vapour
pressure deficit have been estimated as monthly average by using NOAA-AVHRR satellite data in the
thermal range. Generally, land surface temperature has been retrieved from two thermal infrared bands
(channels 4 and 5 of AVHRR of NOAA) located at 11 µm and 12 µm by using split-window equations.
The split-window algorithms are belonged to the difference in the brightness temperatures of thermal
infrared bands. Furthermore, land surface temperature depends on the magnitude of the difference between
the two grounds emissivity in the bands[8,7].
2 METHODOLOGY AND DATA SOURCES
In this study, GSR was predicted for 53 locations by using ELM, SVR, KNN, LR and NU-SVR
methods. Methods were trained with a two-year data set and accuracy of the mentioned methods was tested
with a one-year data set. The data set of each year was consisting of 12 months. Whereas the values of
month, altitude, latitude, longitude, vapour pressure deficit and land surface temperature were used as input
for developing models, GSR was obtained as output. Values of vapour pressure deficit and land surface
temperature were taken from radiometry of NOAA-AVHRR satellite. Estimated solar radiation data were
compared with actual data that were obtained from meteorological stations.
ELM has a very valuable methods of modeling tools, many of them with a proven track record in
applications. We may consider here Support Vector Regression, one of the workhorses in nonlinear
modeling, and, alternatively, we shall also work with two versions of SVR which depends only on a subset
of the training data and NU-SVR, which was later developed where the epsilon penalty parameter was
replaced by an alternative parameter, nu [0,1], which applies a slightly different penalty .In pattern
recognition, the k-NN is a non-parametric method used for classification and regression. [9].LR measures
the relationship between the categorical dependent variable and one or more independent variables by
estimating probabilities using a logistic function, which is the cumulative logistic distribution.
2.1 Support Vector Regression
The main purpose of the SVR algorithm in time series forecasting [10] is to find a function that for
each vector 𝑥⃗⃗ ∈ 𝑅 𝑛
representing a time series within a dataset with N training time series sequences
approximates its value (𝑖 ≥ 0 ≤ 𝑁) as closely as possible. The result give us fundamentals for forecasting.
When the input data are amenable to linear regression, SVR is defined by the equation (1);
𝑦𝑖 = 𝑥𝑖⃗⃗⃗ ∙ 𝑤⃗⃗ + 𝑏 (1)
𝑤⃗⃗ is the weight vector, i.e., a linear combination of training patterns that supports the regression
function.
𝑥𝑖⃗⃗⃗ is the input vector, e.g., the 𝐾 𝑇∗time series training sample.
𝑦𝑖 is the value for the input vector, e.g., the following 𝐾 𝑇∗ values to be predicted.
𝑏 is the bias, i.e.
𝑏
‖𝑤⃗⃗ ‖
is the perpendicular distance from the origin of the vector space to the
hyperplane that separates the data points in the vector space.
3. International Journal of Thales Engineering Sciences (JTHES)
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The objective of regression is to estimate the weight vector 𝑤⃗⃗ with the smallest possible length so
as to avoid overfitting. To ease the regression task, a given margin of deviation 𝜀 is allowed with no penalty,
and a given margin of deviation 𝜀 is allowed with increasing penalty. The minimal length of the weight
vector 𝑤⃗⃗⃗⃗ is obtained by minimizing the loss function subject in equation (2) to the constraint in equation
(3) or equation (4), for 𝜉, 𝜉∗
𝑖
≥ 0. The solution is given by constructing a Lagrange function from the loss
function and the associated constraints, as shown in equation (5) where 𝑎𝑖 and 𝑎∗
𝑖 are Lagrange multipliers
[11]. The training vectors giving nonzero Lagrange multipliers are called support vectors and are used to
construct the regression function. If the input data are not amenable to linear regression, then the vector
data are mapped into a higher dimensional features space using a kernel function UΦ, such as the
polynomial kernel: Φ(𝑤⃗⃗ ) ∙ Φ(𝑥𝑖⃗⃗⃗ ) = (1 + 𝑥𝑖⃗⃗⃗ ∙ 𝑤⃗⃗ )3
.
1
2
‖ 𝑤⃗⃗ ‖2
+ 𝐶 ∑ (𝜉
𝑛
𝑖=1
+ 𝜉∗
𝑖
) (2)
yi − (x⃗ ∙ w⃗⃗⃗ + b) ≤ ε + ξi
(3)
yi − (x⃗ ∙ w⃗⃗⃗ + b) ≥ ε + ξ∗
i
(4)
𝑦𝑖 = ∑ (𝑎𝑖 − 𝑎∗
𝑖
𝑛
𝑖=1
) (𝑥𝑖⃗⃗⃗ ∙ 𝑤⃗⃗ ) + 𝑏, for 0≤ i ≤ 𝑛 (5)
2.2 Extreme Learning Machine
The Extreme Learning Machine (ELM) is based on single hidden layer feed-forward network (SLFN)
as Figure 1. Huang was the first to introduce the extreme learning machine algorithm. It is a new approach
for feed forward networks that has a remarkable speed for mapping the relationship between input(s) and
output(s). ELM creates a hidden layer without needing iterative steps and also computes the output weights
analytically. There are no iterations in ELM, which makes ELM faster than the back propagation technique.
However, there are some drawbacks of the ELM. The first issue is the neurons in the hidden layer have to
be computed by using a trial-and-error procedure. The hidden layer needs more neurons because ELM
generates random values chosen for the weighting matrix [12,13].
Figure 1: Extreme leaning machine process tree.
4. International Journal of Thales Engineering Sciences (JTHES)
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2.2.1 The ELM Algorithm
Suppose that we have training samples (𝑥𝑖
, 𝑡𝑖) where 𝑥𝑖 = [ 𝑥𝑖2, 𝑥𝑖2 … . , 𝑥𝑖𝑛]T
∈ 𝑅 𝑐and and 𝑡𝑖 =
[ 𝑡𝑖2, 𝑡𝑖2 … . , 𝑡𝑖𝑛]T
∈ 𝑅 𝑚. From these samples, an ELM model is trained with k hidden neurons and an
activation function𝑔(𝑥). When ELM approximate training samples with zero error, we will obtain
∑ ‖𝑦𝑗 − 𝑡𝑗‖
𝑘
𝑗=1
= 0. In other words, 𝑤𝑖, 𝑏𝑖 𝑎𝑛𝑑 𝑥𝑖 such that [14]:
∑ 𝛽𝑖 𝑔(𝑤𝑖, 𝑏𝑖, 𝑥𝑗)
𝑘
𝑖=1
= 𝑡𝑖 (6)
The 𝑤𝑖 is the input weight connected between input and hidden layers, 𝑏𝑖 is the bias of the hidden
layer, and is 𝑥𝑖 the input sample. The equation (6) can be written as [14].
𝛨𝛽 = 𝛵 (7)
Where
Η = [
𝑔(𝑤1, 𝑏1, 𝑥1) ⋯ 𝑔(𝑤 𝑘, 𝑏 𝑘, 𝑥1)
⋮ ⋱ ⋮
𝑔(𝑤1, 𝑏1, 𝑥 𝑁) ⋯ 𝑔(𝑤 𝑘, 𝑏 𝑘, 𝑥 𝑁)
]
Nxk
(8)
𝛽 = [
𝛽1
.
.
𝛽 𝑘
] (9)
Τ = [
Τ1
.
.
Τ 𝑘
] (10)
Η: is the hidden layer output
𝛽: is the output weight
Τ: is the target
𝛽 = Η+
Τ
Η: is the Moore-Penrose generalized (pseudo-inverse) inverse. The orthogonal project method is used to
calculate the Moore-Penrose generalized inverse of the matrix [14].
The ELM design involves four steps:
1. Dividing the data onto three subsets (training set, testing set, predicting set).
2. Generating the weight values randomly (w).
3. Computing the hidden layer output matrix (Η).
4. Computing the output weight (𝛽 ).
2.3 Linear Regression
Regression analysis is a statistical technique for investigating and modeling the relationship between
variables as equation [15]. In fact, the regression analysis is the most widely used statistical technique. The
simple linear regression model used is a model with a single independent variable x that has a relationship
with a response variable y that is a straight line. This simple linear regression model is given by;
y = β0 + x1. β1 + ε (11)
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Where the intercept 𝛽0 and the slope 𝛽1 are unknown constant and 𝜀 is a random error. The errors
are assumed to have mean zero and unknown variance 𝜎2
. The parameters 𝛽0 and 𝛽1 are unknown and
must be estimated using sample data. The simple linear regression equation is also called the least squares
regression equation. It tells the criterion used to select the best fitting line, namely the sum of the squares
of the residuals should be least. That is, the least squares regression equation is the line for which the sum
of squared residuals ∑ (𝑦𝑖 − 𝑦𝑖̂)2n
𝑖=1
is a minimum.
2.4 k-Nearest Neighbours
The k-nearest neighbors [16, 17] is a method for classifying objects based on closest training
examples in the feature space. k-NN is a type of instance-based learning, or lazy learning where the function
is only approximated locally and all computation is deferred until classification. It can also be used for
regression. Unlike previous models, this tool does not use a learning base. The method consists in looking
into the history of the series for the case the most resembling to the present case. By considering a series of
observations 𝑋𝑡, to determine the next term 𝑋𝑡+1, we must find among anterior information, which
minimize the quantity defined on equation.(12) (d is the quadratic error).
r0 = argmin(d(Xt, Xt−r) + d(Xt−1, Xt−r−1) + … . . d(Xt−k,Xt−r−k) (12)
In this study we have chosen a k equal to 10. After this argument of the minimum search, the
prediction can be written as equation (13):
Xt+1 = Xt+r0+1 (13)
2.5 Nu-support Vector Regression
This is a most commonly used versions of SWM. The original SVM formulations for Regression
(SVR) used parameters C [0, inf) and epsilon [0, inf) to apply a penalty to the optimization for points which
were not correctly predicted. An alternative version of both SVM regression was later developed where the
epsilon penalty parameter was replaced by an alternative parameter, nu [0,1], which applies a slightly
different penalty. The main motivation for the nu versions of SVM is that it has a more meaningful
interpretation. This is because nu represents an upper bound on the fraction of training samples which are
errors (badly predicted) and a lower bound on the fraction of samples which are support vectors. Some
users feel nu is more intuitive to use than C or epsilon. Epsilon or nu are just different versions of the
penalty parameter. [18]
The user must provide parameters (or parameter ranges) for SVM regression as:
'epsilon-SVR':
epsilon,C, (using linear kernel), or
epsilon,C, gamma (using radial basis function kernel),
'nu-SVR':
nu, C, (using linear kernel), or
nu, C, gamma (using radial basis function kernel).
2.5.1 Svm Parameters
Cost: Cost [0 ->inf] represents the penalty associated with errors larger than epsilon. Increasing cost
value causes closer fitting to the calibration/training data. Gamma: Kernel gamma parameter controls the
shape of the separating hyperplane. Increasing gamma usually increases number of support vectors.
Epsilon: In training the regression function there is no penalty associated with points which are predicted
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within distance epsilon from the actual value. Decreasing epsilon forces closer fitting to the
calibration/training data. Nu: Nu (0 -> 1] indicates a lower bound on the number of support vectors to use,
given as a fraction of total calibration samples, and an upper bound on the fraction of training samples
which are errors (poorly predicted).
3 EVALUATION OF THE ESTIMATION RESULTS
The choice of the relevant criteria allowing performance evaluation of the estimation methods is an
important issue. Various statistical parameters can be used to measure the strength of the statistical
relationship between the estimated values and the reference values. I assume that vi, (i = 1, n) is the set of
n reference values and ei, (i = 1, n) is the set of the estimates. v̅ and e̅ are mean of reference and estimates
values respectively. The bias, R, RMSE and MBE can be calculated by using standard deviations of
reference (σv) and estimate (σe) values, mean of reference and estimates values, estimated values and the
reference values. The bias which is the difference between the mean estimate e̅ and the mean reference
value v̅. The statistical criteria formula of the linear correlation coefficient R is the following,
1
( )( )
n
i i
i
v e
v v e e
r
n
(14)
Where R measures the proximity between estimate and reference. It is not sensitive to a bias [20].
The formula of the RMSE is;
1
2 2
1
1
( )
n
i i
i
R M S E e v
n
(15)
In statistics, RMSE is a frequently used measure of the differences between values predicted by a
model or an estimator and the values actually observed from the thing being modeled or estimated [19].
MBE is;
MBE
1
1
n
i i
i
e v
n
(16)
When you compared actual value with the estimating result Mean Bias Error (MBE) is expected least
value [21]. Ideal MBE is expected to approach zero. MBE can be negative or positive value. This is not
important. MBE value is calculated with equation (16).
4 CONCLUSION
In this study, 2000, 2001 and 2002 years, GSR was estimated by using NOAA/AVHRR monthly
mean land surface temperature and vapour pressure deficit. In addition to land surface temperature and
vapor pressure deficit data, values of month, altitude, latitude, longitude were used to calculate GSR. In this
estimating, GSR was estimated by depending on mentioned input parameters. Also ELM, SVR, KNN, LR
and NU-SVR methods were used to train network. While input data of 2000 and 2001 year, were used to
train network, data of 2002 year is used to test training network. Number is 53 for both intended training
location and testing location. The obtained estimating results that depend on location, are evaluated with
actual values statistically. As shown table 1.
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Table 1 Comparison of methods statistically.
METOT MBE(MJ/m2
) RMSE(MJ/m2
) R
ELM -0,2640 1,7746 0,9612
SVR -0,0043 1,9599 0,9515
k-NN 0,1450 2,4546 0,9250
LR 0,1588 5,2533 0,7243
Nu-SVR -0,2652 1,4972 0,9728
When table 1 is examined, The highest correlation coefficient value have been found 0,9728. This
result have been obtained by using Nu-SVR method. The lowest correlation coefficient value have been
found 0,7243. The obtained result have been got by using LR method. On the other hand, MBE values of
other methods is calculated. The lowest MBE value have been found 0,0043 MJ/m2. The obtained result
have been got by using SVR method. The highest MBE value have been calculated 0,2652 MJ/m2. This
result have been obtained by using Nu-SVR method. RMSE value also was calculated, which is important
to compare statistically. According to the results, lowest RMSE value is 1,4972 MJ/m2, which have been
obtained by using Nu-SVR method. So, It proved that this is the most successful method to estimate GSR.
, The highest RMSE value have been got by using LR method with 5,2533 MJ/m2 and also it proved that,
this is the least successful method to estimate GSR. Other methods RMSE values are varying between
1,7746 MJ/m2 and 2,4546 MJ/m2. These results shows that, ELM, SVR, k-NN methods are enough for
calculation.
Correlation coefficient (R) of locations, MBE, RMSE have been calculated by using the best method
Nu-SVR.
Table 2 Statistical results of locations.
LOKASYON MBE(MJ/m2
) RMSE(MJ/m2
) R
Amasya -0,2008 1,2280 0,9812
Antakya 0,3185 0,6428 0,9946
Antalya -2,0519 2,3409 0,9852
Balıkesir -0,4160 1,4705 0,9713
Bingol 1,1040 1,9876 0,9772
Bitlis -1,6446 1,9315 0,9875
Bursa 0,1060 1,2798 0,9749
Diyarbakır -0,1068 1,0857 0,9877
Denizli -0,7700 1,4644 0,9737
Edirne -1,8345 2,1111 0,9887
Gaziantep -0,2504 0,8017 0,9914
Gümüshane -1,1129 1,5437 0,9883
Hakkarı 0,3520 1,6268 0,9727
Igdır -0,4361 1,3683 0,9753
İstanbul -0,1089 1,0919 0,9865
İzmir -1,0915 1,8261 0,9800
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Konya -0,5819 1,5929 0,9720
Malatya 0,0596 0,8032 0,9921
Mersin -0,4025 0,9471 0,9928
Mus -0,5218 1,2138 0,9902
Nigde -0,5780 1,2077 0,9868
Ordu 0,2149 1,2800 0,9761
Rize 0,4234 1,2807 0,9698
Siirt -1,0340 1,5446 0,9818
Silifke -0,0187 0,6101 0,9941
Sinop 1,7321 2,9830 0,9470
Sanlıurfa -0,0859 1,5290 0,9738
Yalova -0,2657 1,0187 0,9902
Yozgat -0,2994 1,3885 0,9737
Zonguldak 0,2709 1,1093 0,9897
Adana -0,5986 0,9866 0,9895
Adıyaman 0,0070 0,5777 0,9945
Agrı -0,4485 1,3172 0,9751
Aksaray 0,1322 1,1816 0,9833
Aksehir -0,3475 1,7290 0,9607
Ankara -0,3934 1,0495 0,9881
Artvin -0,2011 1,3190 0,9737
Aydın -1,4823 2,1600 0,9716
Batman 2,0765 2,8554 0,9890
Bilecik -0,5977 1,2318 0,9827
Birecik -0,0764 0,6547 0,9949
Burdur -0,5421 1,4751 0,9781
Canakkale -1,1734 1,6766 0,9829
Corum 0,0200 1,1022 0,9831
Elazığ -0,4757 1,0445 0,9913
Erzincan 0,0946 0,8903 0,9896
Isparta 1,7653 3,1973 0,8993
Kahramanmaras 0,0370 0,8804 0,9917
Karaman -0,0706 1,2628 0,9824
Karatas -1,1071 1,2870 0,9908
Kars -0,3083 0,5266 0,9962
Kastamonu -0,3836 1,4785 0,9526
Kayseri -0,7520 1,3260 0,9863
When table 2 is examined, The highest correlation coefficient value have been found 0,9962. This
result have been obtained from Kars location. The lowest correlation coefficient value have been calculated
0,8993. This result have been obtained from Isparta location. The lowest MBE value have been
calculated0,007 MJ/m2. This result have been obtained from Adiyaman location. The highest MBE value
is 2,0765 MJ/m2which have been obtained from Batman location. The highest RMSE value have been
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obtained 3,1973 MJ/m2.This result have been obtained from Isparta location. So the worst result have been
obtained from Isparta location by using Nu-SVR method. The lowest RMSE value have been calculated as
0,5266 MJ/m2. The related value is belong to Kars location. So that, the best result have been obtained Kars
location.
Figure 2 : GSR variation of Kars location monthly.
Figure 2 shows 2002 year GSR variation of Kars location monthly. When we examine the variation,
we can observed that estimated value and actual value is very close to each other. The first, fifth, ninth,
tenth month's value are more compatible. It has been observed. We cannot say the same for the third and
sixth month.
As a result, estimating was practiced by using 53 many locations. ELM, SVR, KNN, LR and NU-
SVR methods were used to estimate GSR. Month, altitude, latitude, longitude, vapour pressure deficit and
land surface temperature were used to train networks of methods, as input parameters. These obtained
results have been evaluated statistically. The best result have been obtained by using Nu-SVR method. On
the other hand, the worst result have been obtained by using LR method. Also the other methods gave
compatible results. If researcher study estimating of GSR we may offer them to use ELM, SVR, KNN, and
NU-SVR methods.
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