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Hydrological time series prediction by extreme machine learning and sparrow search algorithm

Bao-fei Feng, Yin-shan Xu, Tao Zhang, Xiao Zhang
2021 Water Science and Technology : Water Supply  
In general, accurate hydrological time series prediction information is of great significance for the rational planning and management of water resource system.  ...  Based on several performance evaluation indexes, the results show that the proposed method outperforms several ELM variants optimized by other evolutionary algorithms in both training and testing phases  ...  K. & Liu, S. 2021b Multi-strategy gravitational search algorithm for constrained global optimization in coordinative operation of multiple hydropower reservoirs and solar photovoltaic  ... 
doi:10.2166/ws.2021.419 fatcat:jaaw26szxffftg65vhur6kcecu

A review of the hybrid artificial intelligence and optimization modelling of hydrological streamflow forecasting

Karim Sherif Mostafa Hassan Ibrahim, Yuk Feng Huang, Ali Najah Ahmed, Chai Hoon Koo, Ahmed El-Shafie
2021 Alexandria Engineering Journal  
A multifunctional reservoir operation appears to require the operator to make wise decisions to achieve an optimal reservoir operation.  ...  However, due to the major global climate changes which affect rainfall trend and weather, it has been a necessity to find an alternative solution for effective conventional water balance.  ...  A study on how to optimize multiple hydropower reservoir operations in 2017 adopts the (ABC) algorithm based on historical inflow data [43] .  ... 
doi:10.1016/j.aej.2021.04.100 fatcat:fppujuentje67dekhgnfe5qt3y

Feedback Linearization and Reaching Law Based Sliding Mode Control Design for Nonlinear Hydraulic Turbine Governing System

Bicheng Guo, Jiang Guo
2019 Energies  
Three operating scenarios are simulated compared with the PSO-PID method, and results imply that the proposed SMC method equips with accurate trajectory tracking ability and smooth responses.  ...  This expansion calls for more accurate scheme design in hydraulic turbine governing system (HTGS) to ensure its high efficiency.  ...  The particle swarm optimization (PSO) algorithm, one of many evolution algorithms aiming at searching for a suitable solution from populational sets [35] , and its variants are populated in PID parameters  ... 
doi:10.3390/en12122273 fatcat:zktsgvy4yrfyhfycznwsaptgkq

Probabilistic Price Forecasting for Day-Ahead and Intraday Markets: Beyond the Statistical Model

José Andrade, Jorge Filipe, Marisa Reis, Ricardo Bessa
2017 Sustainability  
In terms of point forecast, the mean absolute error was 3.03 e/MWh for day-ahead market and a maximum value of 2.53 e/MWh was obtained for intraday session 6.  ...  Moreover, these markets also require the inclusion of multiple explanatory variables, which increases the complexity of the model without guaranteeing a forecasting skill improvement.  ...  Acknowledgments: The research leading to this work is being supported by (a) InteGrid project (Demonstration of INTElligent grid technologies for renewables INTEgration and INTEractive consumer participation  ... 
doi:10.3390/su9111990 fatcat:6ve2kjysvzhevpfzkjwbmomfbq

International Journal of Emerging Trends in Electrical and Electronics (IJETEE) International Journal of Emerging Trends in Electrical and Electronics Numerical Differential Protection of Power Transformer using GA Trained ANN

Cher Tan, Ming, Dhrubes Biswas, Rajesh Gupta, Sumana Gupta, A Saxena, Vijay Kumar, Shaibal Mukherjee, S Parida, Kumar Manoj, Meshram, Satyabratajit (+58 others)
2013 unpublished
This paper presents the use of ANN as a pattern classifier for differential protection of power transformer, which makes the discrimination among normal, magnetizing inrush, over-excitation, external fault  ...  Comparing the simulated results of the above two cases, training the neural network by Genetic algorithm gives more accurate results (in terms of sum square error) and also faster results than Back Propagation  ...  The basic operations of natural genetics-reproduction, crossover and mutation are implemented during numerical optimization.  ... 

A study of technical and regulatory issues for integration of distributed generation to medium voltage networks

A. Ramdhin, S. Chowdhury
2017 2017 IEEE AFRICON  
Tzimas for the scientific review of this work. The authors are also grateful to Ms. C.J. Saull for the linguistic check of this study.  ...  With purely sinusoidal functions, the power factor is the cosine of the phase angle (φ) between the current and voltage sinusoid waveforms. It is known as "cosφ" for this reason.  ...  The significant global advantages of small hydropower must not prevent the identification of burdens and impacts at local level nor the taking of necessary mitigation actions.  ... 
doi:10.1109/afrcon.2017.8095636 dblp:conf/africon/RamdhinC17 fatcat:tzrweosbbvc6nmanry7duagxmi

Book Review: Wind and Solar Power Systems—Design, Analysis, and OperationWind and Solar Power Systems—Design, Analysis, and Operation; PatelMukund R., Taylor and Francis Group/CRC, 2nd edition2006 (ISBN 0-8493-1570-0, xvi + 448 pages)

2006 Wind Engineering : The International Journal of Wind Power  
Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their  ...  Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed.  ...  In a multiple-machine wind farm, each turbine must be controlled by its own control loop with operational and safety functions incorporated.  ... 
doi:10.1260/030952406778606197 fatcat:ay2pnjxi5rhs7ndqhwmwsya2zm

Enhancement of the REMix energy system model : global renewable energy potentials, optimized power plant siting and scenario validation [article]

Daniel Stetter, Universität Stuttgart, Universität Stuttgart
a European to a global scale, (ii.) adding a new plant siting optimization module REMix-PlaSMo, capable of assessing siting effects of renewable power plants on the portfolio output and (iii.) adding  ...  A detailed global land use analysis determines eligible sites for the installation of renewable power plants.  ...  The latter is derived as a function of the solar multiple.  ... 
doi:10.18419/opus-6855 fatcat:cphja63ucrhmxntllyjahmftri

Machine learning estimation of snow water equivalent over British Columbia [article]

Andrew Matthew Snauffer
The full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.  ...  This elapsed year fraction is modeled using trigonometric predictors (sine and cosine) as it is a periodic signal.  ...  As the objective function J has multiple local minima, the nonlinear optimization algorithm starting with different random initial weights and offset parameters could converge to different local minima  ... 
doi:10.14288/1.0363029 fatcat:6k3uzv2bq5fazlkp3r4vpuij3i

Analytical design of a transverse flux machine [article]

MFJ Maarten Kremers, JJH Johannes Paulides, EA Elena Lomonova
The magnetic flux density on the current sheets along the z-axis over a period of two pole pitches can be expressed as a Fourier series of sines and cosines: B z = ∞ m=0 ∞ n=0 a m,n cos ω x,n x + x cos  ...  Additionally, the rivers are used for multiple purposes which makes a combination with hydropower of some magnitude impossible.  ... 
doi:10.6100/ir851759 fatcat:duqmc3rexrafpo3oqrfab5koeu

Application Of The Genetic Algorithm To An Ecological Simulation

William Seufzer
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.  ...  The reservoir system provides irriga tion and hydropower production; operational policies for the system axe complicated by this dual purpose.  ...  A search algorithm, the Genetic Algorithm (GA), has been used for optimization and has the attrib u te of being a global search algorithm ; there is no single first guess to limit the search around a local  ... 
doi:10.25773/v5-sv9a-rj53 fatcat:qedsdm2iirdehjjknmguouv2cy

Stream temperature modeling in mountainous environments

Aurélien Gallice
Je mesure toute ma chance d'avoir pu conserver un tel groupe d'amis depuis le lycée. . . à part quand il s'agit de trouver des gens motivés pour jouer à Small World.  ...  Et bien sûr, un immense merci à toi, Emilie, pour ta patience et ton amour.  ...  Acknowledgements Albeit generally considered as a personal work, a thesis necessarily leaves you indebted to a long list of people. I hope not to have forgotten anyone of importance here.  ... 
doi:10.5075/epfl-thesis-7160 fatcat:oce2pher7ffwdamdz4q7s2cudu

Turbulent Transport in Complex, Alpine Environments

Holly Jayne Oldroyd
Nikki Vercauteren and Marco Giometto for lively and helpful discussions regarding the subject matter of this paper, and to Derek Jensen of the MATERHORN campaign for assistance with the PLAYA data set.  ...  We are also grateful for logistical support from the Crans-Montana ski resort, and for the field assistance from the many members of the Environmental Fluid Mechanics and Hydrology (EFLUM) laboratory at  ...  Furthermore, an automated algorithm may not be possible due to the insensitivities of the cost functions to increased sector size (as discussed above in Sect. 2.3.3) and the fact that the global minima  ... 
doi:10.5075/epfl-thesis-6594 fatcat:r4v6nhbjxzfs3ofxmcml2hkhgy

Exploring multi-annual changes in the biophysical environment of the Black Sea

Valérie Le Guennec
strong efforts for the development of accurate algorithms.  ...  Harmonic analysis The goal of this section is to introduce the method used to reconstruct a periodic signal using both sine and cosine waves with the frequency .  ...  each grid cells) and the associated river flow (kg m -2 s -1 ) (right value in each grid cells). The number of grid cells corresponds to the number of cells used to spread the discharge. Months\  ... 
doi:10.17638/03106702 fatcat:lp3hotbezbdgpk6apxye7wzbcq

Biophysical considerations in integrated catchment management : a modelling system for Northern Thailand [article]

Wendy Sue Merritt, University, The Australian National, University, The Australian National
A trend in environmental modelling and policy making has been to move towards the use of integrated assessment methodologies as a means of balancing what are most usually multi-issue problems with multiple  ...  This thesis presents a Biophysical Toolbox that integrates models for assessment of the outcomes of biophysical scenarios of water and land use options.  ...  too high and thus a sine/ cosine function proposed by Meijerink (1989) was applied, where; LS= [(length(mJ)/22.1) x6.4 Xsin(sloper°J) xcos(sloper 0 J) LS= (0.799 + O.OJOJ(length(mJ))(0.344 + 0.798(slope  ... 
doi:10.25911/5d74e90831331 fatcat:jwir7xvn3vbwza5ri7evf2nrne
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