摘要:
Hopfield neural networks are favored by academia and industrial fields due to their abundant dynamics. In this paper, the dynamical behavior of a small Hopfield neural network (HNN) simultaneously stimulated by electromagnetic radiation and multi-level-logic pulse is investigated. Firstly, a modified HNN with three neurons is presented by selecting appropriate synapse weight coefficients. And the system model of the HNN under electromagnetic radiation and an electrical pulse is constructed. Then its equilibrium stabilities and nonlinear dynamical phenomena are analyzed by using numerical analysis methods including phase portraits, Lyapunov exponents, and bifurcation diagrams. The research results show that the neural network affected by electromagnetic radiation and a multi-level-logic pulse signal can generate chaotic multi-scroll attractors, which has not been observed in the previous investigation for the Hopfield-type neural networks. In addition, the number of the scroll can be easily changed by adjusting the electrical pulse signal. Circuit simulations based on the designed neural network circuit are carried out to confirm the numerical simulations. Finally, an HNN-based image encryption scheme is designed from the perspective of engineering applications. Performance evaluations demonstrate that the proposed image cryptosystem has good security.
摘要:
Purpose Co-composting with agriculture waste and sediment is an effective method to passivate the heavy metal content of sediment, but it is still unclear whether this passivation will be effective in the long term, and the contribution of different components of humic substances (HS) to the passivation of heavy metals has not been investigated quantitatively.Methods A 256-day composting experiment was conducted in 165 L reactors. Sediment, vegetables, rice straw, and bran were used as raw materials. Two experiments were set up, with pile A as control and pile B inoculated with Phanerochaete chrysosporium.Results The results revealed that the residual fraction of Cd (Res-Cd) increased by 24.22% and 27.04% in pile A and pile B, respectively. During the first 60 days of composting, the contents of humic acids-bound Cd (HA-Cd) both increased in two piles and accounted for 16.54% and 17.69% of the total content of Cd (T-Cd) in pile A and pile B, respectively. The correlation analysis suggested that the Res-Cd exhibited a significantly positive correlation with humic acid (HA) (P < 0.01) and HA-Cd, but a negative correlation with fulvic acid (FA) in both piles. Fourier-transform infrared spectroscopy and excitation-emission matrix fluorescence spectroscopy analysis demonstrated that the inoculation could enhance the chelating capability of HA to Cd and improve the maturity of compost.Conclusions This study has demonstrated that composting had a persistent passivation on Cd for 256 days. The contribution of HS to Cd passivation largely depends on the amount of HA-Cd rather than FA-Cd. Moreover, the inoculation of Phanerochaete chrysosporium could enhance the binding ability of HA to Cd and improve the maturity of compost.
期刊:
Journal of Applied Polymer Science,2024年141(1) ISSN:0021-8995
通讯作者:
Xiao, GQ
作者机构:
[Xiao, Guqing; Meng, Qiudong; Xie, Huixian; Song, Qingwen] Hunan City Univ, Coll Mat & Chem Engn, Yiyang 413000, Peoples R China.
通讯机构:
[Xiao, GQ ] H;Hunan City Univ, Coll Mat & Chem Engn, Yiyang 413000, Peoples R China.
关键词:
adsorption;glyphosate;ionic radius;resins
摘要:
Abstract La3+ and Al3+ loaded D151 resin [R‐La and R‐Al, respectively] were used as salt‐resistant resins for the efficient adsorption of glyphosate. The results showed that La3+ with a larger ionic radius could accommodate more glyphosate as ligands, resulting in higher glyphosate adsorption capacity of R‐La than that of R‐Al. Both R‐La and R‐Al exhibited maximum adsorption capacities at pH 2.52, where glyphosate existed in its ionization equilibrium of pKa2. Consistent with the larger ionic radius of La3+, R‐La featured larger qm and KL than R‐Al at the same temperature. Owing to the smaller radius of Al3+, the enthalpy values for the coordination adsorption of glyphosate by R‐Al were larger than those of R‐La at the same adsorption capacity. Owing to the smaller radius of Al3+, R‐Al exhibited stronger coordination adsorption for glyphosate and significantly higher salt tolerance than R‐La. The adsorption mechanisms indicated that both R‐La and R‐Al could adsorb glyphosate through the coordination of La3+ and Al3+ with O atoms of the phosphonate group of glyphosate. At a NaCl concentration range of 0–16%, R‐Al featured excellent salt tolerance and highly stable glyphosate adsorption capacity than 330, D301, R‐La, and the 14 adsorbents reported in the literature.
作者机构:
[Liu, Bangfu; Liu, BF] Hunan Elect Informat Ind Inst, Jiefangdonglu 51, Changsha 410000, Peoples R China.;[Zhou, Le-zhou] Hunan Prevent & Treatment Inst Occupat Dis, Changsha 410007, Hunan, Peoples R China.;[He, Guo-wen] Hunan City Univ, Coll Mat & Chem Engn, Yiyang 413000, Hunan, Peoples R China.;[Wang, Chaoli] Air Force Mil Med Univ, Dept Pharm, Xian 710000, Peoples R China.
通讯机构:
[Liu, BF ] H;Hunan Elect Informat Ind Inst, Jiefangdonglu 51, Changsha 410000, Peoples R China.
关键词:
Hydrophobic deep eutectic solvents;Stripping back extraction;Complexation;Metal ions;Three-phase separation
摘要:
In this paper, a green hydrophobic deep eutectic solvent (HDES) composed of menthol and hexanoic acid was employed to dissolve cosmetics containing Cd2+ and Cd2+ was extracted using an EDTA-2Na saturated solution, analyzed by FAAS. The study found that HDES-1 can be recycled and reused well; the stability constants of Cd2+ EDTA chelates play an important role in the extracting process; the optimum conditions were: the solubility of HDES-1 was 20 mL/g for cosmetic sample at an indoor temperature of around 10 degrees C; the dissolver-extractant ratio was 2:1; the LOD was 0.037 mg/kg; the RSD was 3.5%; and the recovery was 85.5-118.3%. The developed method was successfully applied to actual cosmetic samples with satisfactory results, and it was also applied for the determination of Mg2+, Mn2+, and Cu2+ in cosmetic samples.
摘要:
Reasonable assessment of the failure probability caused by long-term deflection is essential to ensure the service performance of low shrinkage-creep concrete (LSCC) structures. In this paper, the shrinkage and creep models applicable to LSCC are proposed and verified by comparing their results with the experimental data. Then, the non-stationary evolution models of uncertainties of concrete creep and shrinkage are developed. Finally, a long-term deflection-based assessment method of failure probability of LSCC structures is also proposed considering the effect of non-stationary evolution of creep and shrinkage uncertainties. The case analysis results show that ignoring the effect of the non-stationary evolution of creep and shrinkage uncertainties overestimates the long-term deflection, and the deviation in this case study is 10.13%. Compared with the uncertainty of creep, the cumulative failure probability of the case structure is more sensitive to the non-stationary evolution of shrinkage uncertainty. The use of LSCC can greatly reduce the cumulative failure probability of concrete structures caused by excessive long-term deflection. Additionally, the cumulative failure probability of concrete structures is greatly underestimated by using the traditional characteristic parameters of uncertainties of concrete creep and shrinkage.
期刊:
Water Supply,2023年23(11):4682–4690. ISSN:1606-9749
通讯作者:
Du, LY
作者机构:
[Du, Linyuan; Du, LY] Hunan City Univ, Sch Humanities, Yiyang 413000, Hunan, Peoples R China.
通讯机构:
[Du, LY ] H;Hunan City Univ, Sch Humanities, Yiyang 413000, Hunan, Peoples R China.
关键词:
agricultural water management;drought;irrigation efficiency;water footprint
摘要:
The increasing use of water and the decrease in average rainfall along with climate change have caused the reduction of water resources in arid and semi-arid regions. In addition, despite the consumption of more than half of these resources in the agricultural sector, a rate between 0 and 15% of the price of the products has always been received from the farmers. Considering the concept of virtual water and the water content of products in the form of green water, blue water and gray water, the present research has calculated the economic value of virtual water of agricultural products with the approach of maximizing water use efficiency. The investigated sample includes eight cities (counties) of Sanmenxia, Jiaozuo, Nanyang, Shangqiu, Puyang, Luohe, Luoyang and Kaifeng and six agricultural products (wheat, barley, potato, rapeseed, tomato and corn). A fuzzy dynamic programming model has been used to evaluate the objective function. The results showed that the maximum and minimum economic value of water content (sum of surface and groundwater) of the products were estimated for Kaifeng and Shangqiu regions equal to 1.16 and 0.86 Yuan/m3, respectively.
摘要:
In this study, we present a novel analysis approach for lattice composite cylindrical shells reinforced with Graphene Platelets (GPL) nanoparticles. Our primary contribution lies in the investigation of these advanced structures, incorporating nanocomposite reinforcement, orthotropic inhomogeneity, and semi-analytical methods. The lattice composite comprises an anisogrid lattice laminated shell, reinforced with functionally graded GPL. We model this structure using a global continuous orthotropic deep shell approach, integrating the Halpin-Tsai and rule of mixtures homogenization strategies to estimate equivalent mechanical properties. We derive theoretical formulations utilizing Reddy's third-order shear deformation theory and nonlinear Sanders' kinematic assumptions, tailored for deep thick shells. Nonlinear equilibrium equations are obtained using Hamilton's principle and Hooke's constitutive law, leading to linearized bifurcation equations through adjacent-equilibrium and membrane pre-buckling analysis. Our stability analysis employs a semi-analytical method combining trigonometric expansion and Chebyshev collocation functions. Validation through parametric ex -amples demonstrates the accuracy and efficiency of our approach, unveiling insights into the impact of lattice composite and geometric parameters on the stability response of these innovative structures.
摘要:
Efflorescence is a concerning issue in geopolymer formulations. By accelerating efflorescence, the efflorescence behavior and compressive strength evolution were analyzed for metakaolin (MK)-based geopolymers cured at various temperatures and times. Mercury Intrusion Porosimetry (MIP) was the primary characterization method utilized in this study. Based on the pore structure, we identified the influence of pore structure on efflorescence behavior and compressive strength evolution. Those results showed that long-term and initial high-temperature curing played a negative role in mitigating efflorescence. Long-term curing refined the pore size, facilitating alkali salt migration to the surface. Initial high-temperature curing enhanced pore connectivity, which facilitated alkali salt movement. The number of pores below 20 nm governs the effect of efflorescence on compressive strength. Crystallization degrades geopolymer with a large number of pores below 20 nm. This study provides a new understanding of the effect of pore structure on efflorescence and the evolution of compressive strength during efflorescence and facilitates optimization of geopolymer formulations to relieve efflorescence.
通讯机构:
[Chen, Yaoning] K;[Li, Yuanping] C;Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China. Electronic address:;College of Municipal and Mapping Engineering, Hunan City University, Yiyang, Hunan 413000, China. Electronic address:
摘要:
Humic substances (HSs) are key indicators of compost maturity and are important for the composting process. The application of additives is generally considered to be an efficient and easy-to-master strategy to promote the humification of composting and quickly caught the interest of researchers. This review summarizes the recent literature on humification promotion by additives in the composting process. Firstly, the organic, inorganic, biological, and compound additives are introduced emphatically, and the effects and mechanisms of various additives on composting humification are systematically discussed. Inorganic, organic, biological, and compound additives can promote 5.58-82.19%, 30.61-50.92%, 2.3-40%, and 28.09-104.51% of humification during composting, respectively. Subsequently, the advantages and disadvantages of various additives in promoting composting humification are discussed and indicated that compound additives are the most promising method in promoting composting humification. Finally, future research on humification promotion is also proposed such as long-term stability, environmental impact, and economic feasibility of additive in the large-scale application of composting. It is aiming to provide a reference for future research and the application of additives in composting.
摘要:
Super-hard abrasive grinding is considered to be the main approach to realize precision and ultra-precision machining of difficult-to-machine materials such as cemented carbide, engineering ceramics, titanium alloys and superalloy materials encountered. However, heavy grinding force, high grinding temperature and poor surface integrity are prone to be encountered in conventional negative rake angle grinding of difficult-to-machine materials. In response to these problems, a novel concept of positive rake angle grinding is first proposed and an abrasive grain regularly arranged binder-less polycrystalline diamond face grinding wheel with positive rake angle has been designed and fabricated by femtosecond laser ablation. To evaluate the grinding performance of the face grinding wheel with positive rake angle, grinding experiments of YG8 cemented carbide are conducted and compared with the traditional electroplated diamond grinding tool with equivalent abrasive grain dimension and distribution. The results show that compared with the conventional negative rake angle grinding, the normal and tangential forces in positive rake angle face grinding are reduced by 30.3 % similar to 36.4 % and 21.1 % similar to 29.3 %, respectively, and the ratio of normal to tangential force is reduced by 12.6 % similar to 20.3 %. The surface roughness and average depth of subsurface metamorphic layer are also significantly smaller. The laser fabricated polycrystalline diamond face grinding wheel also has better wear resistance in the grinding of cemented carbide. Therefore, it can be concluded that better ground surface quality is obtained by the novel grinding wheel with positive rake angle. The innovative grinding method can fill the research gap on the grinding mechanism of positive rake angle grinding and further enrich the grinding theory of difficult-to-machine materials.
作者机构:
[Luo, Xiaoyong; Long, Hao; Dong, Shuang; Luo, XY; Liu, Jinhong] Cent South Univ, Sch Civil Engn, Changsha 410000, Peoples R China.;[Long, Hao] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Luo, Xiaoyong; Luo, XY] Cent South Univ, Hunan Prefabricated Bldg Engn Technol Res Ctr, Changsha 410000, Peoples R China.
通讯机构:
[Luo, XY ] C;Cent South Univ, Sch Civil Engn, Changsha 410000, Peoples R China.;Cent South Univ, Hunan Prefabricated Bldg Engn Technol Res Ctr, Changsha 410000, Peoples R China.
关键词:
prefabricated components;tolerance;manufacturing dimensions;dimensional chain;monte carlo method;installation reliability
摘要:
Abstract: During the installation process of prefabricated components, deviations in dimensions and installation positions can occur due to construction quality issues, and the accumulation of these deviations can impact the reliability of component installation. However, the current approach to addressing accumulated deviations in the component installation process primarily relies on the trial-and-error method, lacking a solid theoretical foundation. This paper introduces the dimensional chain theory derived from mechanical engineering and presents a method to evaluate the installation reliability of prefabricated components in concrete structures. First, based on extensive measurements of installation deviations, it was found that the installation deviations of components followed a log-normal distribution. By analyzing the relationship between installation deviations and the acceptance rate, it was determined that for a 90% acceptance rate, the installation position deviation should be 8.6 mm for prefabricated wall panel components and 7.3 mm for prefabricated column components. Subsequently, the concept of dimensional chain theory from mechanical engineering was introduced to establish a limit state equation for quantifying the installation reliability of prefabricated components in concrete structures. By applying this theory, appropriate component fabrication dimensions could be determined to achieve a 95% level of installation reliability. Finally, by using the Monte Carlo method to solve the installation limit state equation for an actual engineering project, recommended fabrication dimensions for the components were obtained. The results indicate that within the horizontal axis, the length deviation of prefabricated beams, and the width fabrication dimension of columns needed to be reduced by 2.3 mm to 2.9 mm. Within the vertical axis, the length dimension of columns and the height dimension of beams had to be reduced by 0.9 mm to 2.2 mm to achieve a 95% level of installation reliability. Keywords: prefabricated components; tolerance; manufacturing dimensions; dimensional chain; monte carlo method; installation reliability
作者机构:
[Hu, Xiaojie; Dong, Fuxiao; Wang, Haiou; Zhao, Bojun; Huo, Dexuan; Wang, Yan] Hangzhou Dianzi Univ, Inst Mat Phys, Key Lab Novel Mat Sensor Zhejiang Prov, Hangzhou 310018, Peoples R China.;[Tan, Weishi] Hunan City Univ, Coll Informat & Elect Engn, All Solid State Energy Storage Mat & Devices Key L, Yiyang 413002, Peoples R China.;[Tan, Weishi] Nanjing Univ Sci & Technol, Dept Appl Phys, Key Lab Soft Chem & Funct Mat, Minist Educ, Nanjing 210094, Peoples R China.
通讯机构:
[Weishi Tan] A;[Haiou Wang] K;All-Solid-State Energy Storage Materials and Devices Key Laboratory of Hunan Province, College of Information and Electronic Engineering, Hunan City University, Yiyang 413002, China<&wdkj&>Key Laboratory of Soft Chemistry and Functional Materials, Ministry of Education, Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, China<&wdkj&>Key Laboratory of Novel Materials for Sensor of Zhejiang Province, Institute of Material Physics, Hangzhou Dianzi University, Hangzhou 310018, China
关键词:
magnetic properties;magnetocaloric;manganite;film;Pr0.7Sr0.3MnO3
摘要:
Abstract: The magnetic behaviors and magnetocaloric effect (MCE) of Pr0.7Sr0.3MnO3 (PSMO-7) film grown on a (001) SrTiO3 single-crystal substrate by a pulsed laser deposition (PLD) were studied in this paper. X-ray diffraction with a high resolution (HRXRD) measurement shows that PSMO-7 film is grown with a (001) single orientation. The magnetic properties and the MCE related to the ferromagnetic (FM) phase transition of the PSMO-7 film are investigated using the temperature dependence of magnetization M(T) and the magnetic field dependence of magnetization M(H). The M(T) data suggest that with decreasing temperatures, the PSMO-7 film goes through the transition from the paramagnetic (PM) state to the FM state at around the Curie temperature (TC). The TC (about 193 K) can be obtained by the linear fit of the Curie law. Magnetic hysteresis loop measurements show that the PSMO-7 film exhibits the FM feature at temperatures of 10, 100, and 150 K (low magnetic hysteresis can be found), while the film reveals the PM feature with the temperature increased up to 200 and/or 300 K. The research results of M(H) data are consistent with the M(T) data. Furthermore, the magnetic entropy change ( − Δ S M ) of the PSMO-7 film was studied. It was found that the maximum value of ( − Δ S M ) near TC reaches about 4.7 J/kg·K under the applied field change of 20 kOe, which is comparable to that of metal Gd ( − Δ S M of 2.8 J/kg K under 10 kOe), indicating the potential applications of PSMO-7 film in the field of magnetic refrigeration. Keywords: magnetic properties; magnetocaloric; manganite; film; Pr0.7Sr0.3MnO3
期刊:
FRONTIERS IN EARTH SCIENCE,2023年11:1112772 ISSN:2296-6463
通讯作者:
Gao, H.
作者机构:
[Li, Ping] Tibet Agr & Anim Husb Univ, Coll Resources & Environm, Linzhi, Peoples R China.;[Gao, Hongshan; Yan, Tianqi] Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Minist Educ, Lanzhou, Peoples R China.;[Li, Zongmeng] Xinyang Normal Univ, Sch Geog Sci, Xinyang, Peoples R China.;[Wu, Yajie] Wuwei 1 Middle Sch, Wuwei, Peoples R China.;[Liu, Fenliang] Hunan City Univ, Sch Municipal & Surveying Engn, Yiyang, Peoples R China.
通讯机构:
[Gao, H.] K;Key Laboratory of Western China’s Environmental Systems (Ministry of Education), China
关键词:
downstream fining;gravel-sand transition;median grain size;river sediment;Shiyang River
摘要:
The grain size composition and distribution of river sediments are important for understanding regional geomorphological evolution, source-sink processes and drainage ecology. The Shiyang River basin, an inland river system in northwestern China, provides an environmental context within which to investigate the relationship between sediment particle size and environmental factors. Based on the analysis of the grain size characteristics of modern riverbed sediments, basin geomorphological parameters and lithology, it is found that the median grain size (Md) of river sediments shows a decrease trend from upstream to downstream in the basin. One of the tributaries named the Jinta River shows an obvious downstream fining trend (exponentially decreasing) of Md, which is related to the old geomorphological development stages and relatively homogeneous lithology in the basin. The downstream fining trend of Md along the Xiying River, another tributary, shows complex fluctuations, which might be affected by the tectonically active, young geomorphic development stage, complex lithology of the basin, and the sediment confluence of tributaries. The gravel-sand transition zone occurs in the plain section of the river about 28 km out of the mountain, which is related to the combination of regional geomorphological features, river morphology and hydraulic sorting.
期刊:
Arabian Journal for Science and Engineering,2023年48(4):5683-5683 ISSN:2193-567X
通讯作者:
Tang Wei
作者机构:
[Yang Yalan; Tang Wei] Hunan City Univ, Sch Humanities, Yiyang 413000, Peoples R China.
通讯机构:
[Tang Wei] S;School of Humanities, Hunan City University, Yiyang, China
关键词:
E-commerce;Deep learning network;Data dissemination;Logistic;Cyber security;Integrated learning system based chain management system
摘要:
Recently, the rapid development of e-commerce faces various challenges in information maintenance during online transactions and purchases. Presently, server error and security threats are an interactive method of payment; inconsistent data dissemination issues and prolonged customer waiting time during online purchase and transaction lead to several concerns based on supply chain management during the delivery of products. An essential component of e-commerce is the online transaction portal to ensure specific transactions with conflicts free and ensuring cyber security. Hence, this research develops a deep logistic learning framework (DLLF) to minimize computational time and improve data dissemination accuracy during an online transaction. Furthermore, the DLLF model has been designed based on deep logistic and sampled structure using a controlled network approach and integrated learning system to minimize the computational time and improve accuracy in maintaining customer data. Simulation analysis shows that user behaviors proposed framework analysis improves precision and minimizes computation time during the online purchase effectively with cyber security. The experimental results show DLLF has high efficiency (95.1%), enhanced customer satisfaction (92.6%), less error rate (21.4%), performance rate (94.3%), improved data prediction (91.2%), cost-effectiveness (94.5%), overall production (93.6%) when compared to other methods.
作者机构:
[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.;[Jiang, Jishui] Hunan City Univ, Sch Architecture & Urban Planning, Yiyang 413000, Peoples R China.
通讯机构:
[Li, Z ] C;Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.
关键词:
western Hunan region;Dong;traditional settlement;fire prevention study;Pyrosim simulation
摘要:
Current analytical and simulation models for lithium battery thermal behaviour encounter efficiency or accuracy challenges in energy storage applications. In this paper, an analytical thermal analysis approach for prismatic lithium cells considering dynamic non-uniform characteristics is proposed to calculate the dynamic temperature distribution. A thermal circuit model and analytical differential equation group were formulated to capture the dynamic non-uniform thermal characteristics during charging/discharging. A solving algorithm was provided to balance accuracy and efficiency by establishing an iterative mechanism over the modelling parameters. The proposed model and algorithm were applied to three commercial lithium cells. The experiments under various charge-discharge conditions verified the millisecond-level computational cost and less than 3 % calculation accuracy. The parameter calibration, iteration mechanism, and reproducible codes enhanced the engineering applicability. The performance of the approach suggested its excellent potential in battery thermal management for energy storage.
关键词:
3D Navier-Stokes-Voigt equations;admissible trajectories set;admissible control set;feedback control;time optimal control
摘要:
Abstract: In this article, we discuss a time optimal feedback control for asymmetrical 3D Navier–Stokes–Voigt equations. Firstly, we consider the existence of the admissible trajectories for the asymmetrical 3D Navier–Stokes–Voigt equations by using the well-known Cesari property and the Fillippove’s theorem. Secondly, we study the existence result of a time optimal control for the feedback control systems. Lastly, asymmetrical Clarke’s subdifferential inclusions and asymmetrical 3D Navier–Stokes–Voigt differential variational inequalities are given to explain our main results. Keywords: 3D Navier–Stokes–Voigt equations; admissible trajectories set; admissible control set; feedback control; time optimal control
期刊:
Energy Science & Engineering,2023年11(1):192-205 ISSN:2050-0505
通讯作者:
Changqing Chen<&wdkj&>Yali Wang<&wdkj&>Changqing Chen Changqing Chen Changqing Chen<&wdkj&>Yali Wang Yali Wang Yali Wang
作者机构:
[Chen, Qing Chang; Huang, Liang Zhi] Hunan City Univ, Coll Elect & Informat Engn, Yiyang, Peoples R China.;[Chen, Qing Chang; Zhou, Kui] Hunan Bridge Technol Co LTD, Changsha, Peoples R China.;[Wang, Yali] Changsha Univ Sci & Technol, Sch Econ & Management, Changsha, Peoples R China.;[Wang, Yali] Changsha Univ Sci & Technol, Changsha 410076, Hunan, Peoples R China.;[Chen, Qing Chang] Hunan City Coll, Yiyang 413000, Hunan, Peoples R China.
通讯机构:
[Changqing Chen; Changqing Chen Changqing Chen Changqing Chen] C;[Yali Wang; Yali Wang Yali Wang Yali Wang] S;College of Electrical and Information Engineering, Hunan City University, Yiyang, China<&wdkj&>Hunan Bridge Technology Co., LTD., Changsha, China<&wdkj&>School of Economics and Management, Changsha University of Science and Technology, Changsha, China
关键词:
energy storage;frequency regulation;model predictive control;recovery of SOC;wind farm
摘要:
To further improve the frequency regulation stability of wind farm, and optimize the state of charge (SOC) basepoint, charge and discharge rate and recovery capacity of energy storage. In an isolated, off-grid state, a two-layer optimization method is proposed, taking into account the frequency regulation reliability and SOC adaptive adjustment of the wind storage. In the upper layer, the model predictive control theory is adopted to optimize the energy-storage frequency regulation output power with the goal of minimizing the wind storage frequency regulation power deviation. While solving the problem of low-frequency regulation reliability of wind farm, the SOC recovery basepoint and frequency regulation power of energy storage are optimized. At the SOC optimization layer, based on the upper SOC recovery basis point, we propose a dynamic recovery method for energy-storage SOC that considers both the SOC recovery demand and grid-bearing capacity, to determine the energy-storage recovery power. By determining the frequency regulation or recovery power, we propose a calculation method to optimize the energy-storage charge and discharge coefficients as per the SOC for avoiding excessive charging and discharging. The simulation results show that, under continuous disturbance, the root-mean-square deviations of the proposed method is 80.13% and 62.63% lower than those of the fixed K and SOC methods, respectively. Furthermore, the proposed method exhibits the best SOC maintenance effect.
作者机构:
[Li, Wanting; Huang, Zhiliang; Peng, Li; Yang, Jingyu; Yang, Tongguang] Hunan City Univ, Key Lab Smart City Energy Sensing & Edge Comp Huna, Yiyang 413000, Peoples R China.
通讯机构:
[Li, WT ] H;Hunan City Univ, Key Lab Smart City Energy Sensing & Edge Comp Huna, Yiyang 413000, Peoples R China.
摘要:
To improve the short-term wind power output prediction accuracy and overcome the model prediction instability problem, we propose a combined prediction model based on variational modal decomposition (VMD) combined with the improved whale algorithm (GSWOA) to optimize the long short-term memory network (LSTM) short-term wind power. First, VMD is utilized to decompose the wind power input sequence into modal components of different complexities, and the components are reconstructed into subcomponents with typical characteristics through approximate entropy, which reduces the computational scale of non-smooth sequence analysis. Second, the GSWOA is used to optimize the main influencing parameters of the LSTM model in order to obtain the weights and thresholds under the optimal LSTM model and to use the reconstructed individual subsequences. Finally, the actual data from two wind farms in Xinjiang and Northeast China are taken to verify the generalizability of the proposed model. The comparative analysis of the prediction results under different scenarios demonstrates that the improved model shows higher performance than the original model. (c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).