Jingxin Yu^1,3, Wengang Zheng^1,*, Linlin Xu³, Lili Zhangzhong¹, Geng Zhang², Feifei Shan¹

Intelligent Automation & Soft Computing, Vol.26, No.5, pp. 989-1003, 2020, DOI:10.32604/iasc.2020.010130

Abstract Accurate estimation of reference evapotranspiration (ET0) is a critical prerequisite for the development of agricultural water management strategies. It is challenging to estimate the ET0 of a solar greenhouse because of its unique environmental variations. Based on the idea of ensemble learning, this paper proposed a novel ET0i estimation model named PSO-XGBoost, which took eXtreme Gradient Boosting (XGBoost) as the main regression model and used Particle Swarm Optimization (PSO) algorithm to optimize the parameters of XGBoost. Using the meteorological and soil moisture data during the two-crop planting process as the experimental data, and taking ET0i More >

Asaad H. Sayer¹, Hameed B. Mahood^2,*

Energy Engineering, Vol.117, No.6, pp. 367-379, 2020, DOI:10.32604/EE.2020.011156 - 16 October 2020

Abstract Salinity gradient solar ponds (SGSPs) provide a tremendous way to collect and store solar radiation as thermal energy, and can help meet the critical need for sustainable ways of producing fresh water. However, surface evaporation results in the loss of both water and heat. This study therefore theoretically investigates the effect on temperatures within an SGSP when its surface is covered with a layer of air encased in a nylon bag. An earlier SGSP model was slightly modified to add the air layer and to estimate the temperature distributions of the upper layer or the… More >

D. Menaga¹, M. Premkumar², R. Sowmya^1,*, S. Narasimman³

Energy Engineering, Vol.117, No.6, pp. 481-495, 2020, DOI:10.32604/EE.2020.013282 - 16 October 2020

Abstract The proposed controller accompanies with different sliding surfaces. To understand maximum power point extraction as opposed to nonlinear uncertainties and unknown disturbance of a grid-connected photovoltaic system to various control inputs (u_d, u_q) is designed. To extract maximum power from a solar array and maintain unity power flow in a grid by controlling the voltage across the dclink capacitor (V_pvdc) and reactive current (i_q). A multiple input-output with multiple uncertainty constraints have considered designing proposed sliding mode controllers to validated their robustness performance. An innovative controller verifies uncertain inputs, constant and changes in irradiances, and temperature of More >

Louis Francois Marie^1,*, Sunkara Prudhvi Raj², Policherla Venkata Sai³, Tara MacLeod¹, Morapakala Srinivas², K. Srinivas Reddy³, Tadhg Seán O’Donovan⁴

Energy Engineering, Vol.117, No.5, pp. 323-342, 2020, DOI:10.32604/EE.2020.011035 - 07 September 2020

Abstract Non-centrifugal cane sugar (NCS), known as Jaggery, is a form of unre- fined sugar which contains molasses. The integration of renewable energy resources in the production of NCS, have been analysed. The work investigates the energy requirements of a system incorporating a freeze-concentrator and a solar thermal heater to reduce the reliance on the combustion of bagasse or other fuels in a Jaggery production process. Depending on the extent to which freeze concentration can be incorporated into the process, results show that the minimum theoretical energy required to produce Jaggery can be reduced by 91.30%… More >

Ali Khosravi^1,*, Oscar Ricardo Sandoval Rodriguez², Behnam Talebjedi¹, Timo Laukkanen¹, Juan Jose Garcia Pabon³, Mamdouh El Haj Assad⁴

Energy Engineering, Vol.117, No.5, pp. 249-265, 2020, DOI:10.32604/EE.2020.011024 - 07 September 2020

Abstract The energy coming from solar radiation could be harvested and transformed into electricity through the use of solar-thermal power generation and photovoltaic (PV) power generation. Placement of solar collectors (thermal and photovoltaic) affects the amount of incoming radiation and the absorption rate. In this research, new correlations for finding the monthly optimum slope angle (OSA) on flat-plate collectors are proposed. Twelve equations are developed to calculate the monthly OSA by the linear regression model, for the northern and the southern hemisphere stations from 15° to 55° and –20° to –45°, respectively. Also, a new equation More >

Qinqin Fan^1,*, Yilian Zhang², Zhihuan Wang¹

Intelligent Automation & Soft Computing, Vol.26, No.1, pp. 1-12, 2020, DOI:10.31209/2018.100000042

Abstract Weak global exploration capability is one of the primary drawbacks in teaching learning based optimization (TLBO). To enhance the search capability of TLBO, an improved TLBO (ITLBO) is introduced in this study. In ITLBO, a uniform random number is replaced by a normal random number, and a weighted average position of the current population is chosen as the other teacher. The performance of ITLBO is compared with that of five meta-heuristic algorithms on a well-known test suite. Results demonstrate that the average performance of ITLBO is superior to that of the compared algorithms. Finally, ITLBO More >

Jianjun He^*, Ruifeng Wang, Yefeng Yin, Jian Chen, Chaoran Guo

Energy Engineering, Vol.117, No.4, pp. 185-193, 2020, DOI:10.32604/EE.2020.011181 - 31 July 2020

Abstract TPG-RED (Thermal Power Generation Based on Reverse Electrodialysis) was studied to explore the new method of solar thermal power generating based on Reverse Electrodialysis (RED) in this paper. RED is a process that transfers the salinity gradient between sea water and fresh water to electricity. TPGRED has combined RED with thermal power generation to transfer thermal energy from solar to electricity which has many advantages of huge available temperature range, sustainability, non-pollution, simple structure, and so on. Respectively, using “1 mol/L H₂SO₄ solution—0.0001 mol/L H₂SO₄ solution” and “1 mol/L Na₂SO₄ solution—0.0001 mol/L Na₂SO₄ solution” as the working… More >

Weiming Zhang¹, Muhammad Wasim Khan¹, Xueqin Zuo¹, Qun Yang¹, Huaibao Tang^1,2, Shaowei Jin^1,2, Guang Li^1,2,3,*

Journal of Renewable Materials, Vol.8, No.4, pp. 431-446, 2020, DOI:10.32604/jrm.2020.09158 - 24 April 2020

Abstract A novel sunflower-like nanocomposite of SrCo₂S₄ nanoflakes and functionalized multiwall carbon nanotubes (f-MWCNTs) entanglement enveloped in nitrogen-reduced graphene oxide (N-RGO) is prepared by a cheap process. The unique entanglement structure of the material exhibits higher specific surface area, better electrical conductivity and other properties. This helps to reduce the transfer resistance in the photoelectric process of the battery and improve the electrochemical activity, thus increasing the photoelectric conversion efficiency of the battery. The new ternary cobalt-based sulfide material can replace platinum as the counter electrode (CE) material loaded on dye-sensitized solar cells (DSSCs). DSSCs with SrCo₂S₄@f-MWCNTs@N-RGO More >

J. Serrano-Arellano¹, J. M. Belman-Flores^2,*, I. Hernández-Pérez³, K. M. Aguilar-Castro³, E. V. Macías-Melo³, F. Elizalde-Blancas², J. M. Riesco-Ávila², F. J. García-Rodríguez⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.2, pp. 571-602, 2020, DOI:10.32604/cmes.2020.08677 - 01 May 2020

Abstract In the present study, an analysis of the heat and mass transfer in a ventilated cavity in a warm climate zone was carried out to analyze, among others, the temperatures and percentage of relative humidity (RH). The governing equations of the mathematical model were solved through the finite volume method. We used the k-ε turbulence mode to find the results of the variables of interest in seven climate records on a given day. The velocity of the inlet flow of the air-H₂O mixture was varied through the Reynolds number (Re) from 500 to 10000. The outdoor weather… More >

Jianhua Dong¹, Lifeng Wu², Xiaogang Liu^{1, *}, Cheng Fan¹, Menghui Leng³, Qiliang Yang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.1, pp. 49-73, 2020, DOI:10.32604/cmes.2020.09014 - 01 April 2020

Abstract Solar radiation is an important parameter in the fields of computer modeling, engineering technology and energy development. This paper evaluated the ability of three machine learning models, i.e., Extreme Gradient Boosting (XGBoost), Support Vector Machine (SVM) and Multivariate Adaptive Regression Splines (MARS), to estimate the daily diffuse solar radiation (R_d). The regular meteorological data of 1966-2015 at five stations in China were taken as the input parameters (including mean average temperature (T_a), theoretical sunshine duration (N), actual sunshine duration (n), daily average air relative humidity (RH), and extra-terrestrial solar radiation (R_a)). And their estimation accuracies were subjected to… More >