Search

Through the accurate prediction of power load, the start and stop of generating units in the power grid can be arranged economically and reasonably. The safety and stability of power grid operation can be maintained. First, chicken swarm optimizer based on nonlinear dynamic convergence factor (NCSO) optimizer is proposed based on chicken swarm optimizer (CSO) optimizer. In NCSO optimizer, nonlinear dynamic inertia weight and levy mutation strategy are introduced. Compared with CSO optimizer, the convergence speed and effect of NCSO optimizer are obviously improved. Second, the random parameters of extreme learning machine (ELM) model are optimized by NCSO optimizer, and NCSOELM model is established to predict the power load. Finally, the NCSO optimization extreme learning machine (NCSOELM) model is used to predict the power load, and compared with back propagation (BP), support vector machine (SVM) and CSO optimization extreme learning machine (CSOELM) model. The experimental results show that the fitting accuracy of NCSOELM model is high, and the determination coefficient r 2 is above 90%. And the root mean square error value of the NCSOELM model is 0.87, 0.41, and 0.25 smaller than the root mean square error values of the support vector machine, BP, and CSOELM models, respectively. Experiments show that the model proposed in this study has high fitting effect and low prediction error, which is of positive significance for the realization of economic and safe operation of energy system.

Ethnopharmacological relevance The medicinal plant Morinda officinalis How. (MO) and its root have long been used in traditional medicines in China and northeast Asia as tonics for nourishing the kidney, strengthening the bone and enhancing immunofunction in the treatment of impotence, osteoporosis, depression and inflammatory diseases such as rheumatoid arthritis and dermatitis. Aim of the review This review aims to sum up updated and comprehensive information about traditional usage, phytochemistry, pharmacology and toxicology of MO and provide insights into potential opportunities for future research and development of this plant. Methods A bibliographic investigation was performed by analyzing the information available on MO in the internationally accepted scientific databases including Pubmed, Scopus and Web of Science, SciFinder, Google Scholar, Yahoo, Ph.D. and M.Sc. dissertations in Chinese. Information was also obtained from some local and foreign books on ethnobotany and ethnomedicines. Results The literature supported the ethnomedicinal uses of MO as recorded in China for various purposes. The ethnomedical uses of MO have been recorded in many regions of China. More than 100 chemical compounds have been isolated from this plant, and the major constituents have been found to be polysaccharides, oligosaccharides, anthraquinones and iridoid glycosides. Crude extracts and pure compounds of this plant are used as effective agents in the treatment of depression, osteoporosis, fatigue, rheumatoid arthritis, and infertility due to their anti-depressant, anti-osteoporosis, pro-fertility, anti-radiation, anti-Alzheimer disease, anti-rheumatoid, anti-fatigue, anti-aging, cardiovascularprotective, anti-oxidation, immune-regulatory, and anti-inflammatory activities. Pharmacokinetic studies have demonstrated that the main components of MO including monotropein and deacetyl asperulosidic acid are distributed in various organs and tissues. The investigation on acute toxicity and genotoxicity indicated that MO is nontoxic. There have no reports on significant adverse effect at a normal dose in clinical application, but MO at dose of more than 1000 mg/kg may cause irritability, insomnia and unpleasant sensations in individual cases. Conclusion MO has emerged as a good source of traditional medicines. Some uses of this plant in traditional medicines have been validated by pharmacological investigations. However, the molecular mechanism, structure-activity relationship, and potential synergistic and antagonistic effects of its multi-components such as polysaccharides, oligosaccharides, anthraquinones and iridoid glycosides need to be further elucidated, and the structural feature of polysaccharides also need to be further clarified. Sophisticated analytical technologies should be developed to comprehensively evaluate the quality of MO based on HPLC-fingerprint and content determination of the active constituents, knowing that these investigations will help further utilize this plant. [ABSTRACT FROM AUTHOR]