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This study aims to determine the main factors affecting energy consumption in Jiangxi Province, and to forecast energy consumption effectively. An indicator system of energy consumption influencing factors containing 17 variables is constructed from 4 aspects of economy, society, technology and energy. Based on relevant data from 1996 to 2021, conduct comprehensive analysis and select 10 main factors. Establish three energy consumption prediction models: multiple regression model (MLR), time series model (ARIMA), and support vector regression (SVR). Evaluate the prediction performance through mean square error (MSE), mean absolute percentage error (MAPE), and goodness of fit (R2). The main influencing factors of energy consumption are determined as GDP, output value of the tertiary industry, industrial output value, residents’ consumption level, fixed assets investment of the whole society, total population, urbanization rate, internal expenditure of R&D funds, energy intensity, and energy consumption structure. The best prediction model is SVR model. It provides a basis for the effective formulation of energy policies and the implementation of economic development programs.

Following the national strategies of energy conservation and environmental protection and sustainable development, it is necessary to clarify the requirements for clean energy development to alleviate energy shortage and control environmental pollution, which can provide support for clean energy development projects. Many companies in China have been involved in clean energy development activities under the guidance of preferential national policies and have made a lot of useful attempts, which have so far yielded certain results. Clean energy accommodation involves a wide range of elements, covering economic, technical and policy aspects. In addition, the extremely deep interest relationship exists between new energy generation companies, conventional energy generation companies and users . Due to the complexity of the situation, it is difficult to realize the idea of clean energy consumption in the short term. Based on the “14th Five-Year Plan” development policy system, this paper proposes measures to promote clean energy accommodation around the new energy and hydrogen energy industries. And on this basis, combined with the operation of the electricity market, this paper gives suggestions to promote the level of clean energy consumption in order to have a positive role in promoting energy consumption in China.

In order to correct the error that Efron et al pointed out that the modified Lars is a fast algorithm for lasso problem, computer simulation is carried out with data. The simulation results show that when a variable is removed first and then entered in the lasso problem, the variables selected by lasso and Lars cannot be the same. At this time, no matter how to modify the size of the variables selected by Lars, the lasso problem cannot be solved. The computer simulation method is used to correct the errors of Efron et al in this paper, and contribute to development of world data computing.

An equivalent circuit model of dual polarization (DP) of lithium battery was established according to the application characteristics of lithium battery under the standby condition of 5G base station. On the basis of the model, recursive least square method with forgetting factor (RLS) was used to identify the model parameters. Finally, the Unscented Kalman filtering (UKF) was used to estimate the SOC of lithium battery in real time with the identified model parameters. The simulation and experimental results showed that the combined estimation using recursive least square method with forgetting factor (RLS) and UKF could greatly improve the estimation accuracy of lithium battery SOC, reduce the estimation error, and further verify the accuracy and effectiveness of the whole modeling.

At present, some 600kW and 750kW wind turbines put into operation earlier in China have exceeded their 20-year design life. For these turbines, the safety, reliability and economy of these turbines are usually evaluated in a reasonable way, so as to formulate life extension or decommissioning strategies to maximize economic benefits. Referring to the current international standards and guidelines, this paper takes a wind farm in South China as an example to evaluate the remaining life and state of the turbines. The external environment data of the met mast is extrapolated to the turbine site, and the load simulation is carried out based on the wind turbine model. The fatigue load set of the turbines under the design load condition and the site-specific load condition is obtained. The possible fatigue damage in the historical operation period is calculated. Combined with the linear damage accumulation theory of Miner, the fatigue of each turbine in the site is obtained by load analogy. The final P90 life is obtained by analyzing the uncertainty factors introduced in the assessment of residual life and health status.

To explore the accumulation characteristics of melatonin and underline mechanism in leaves of chinese cherry, the daily changes of melatonin content and the expression of synthetic genes were determined. The results showed that melatonin content increased gradually during the day and midnight, reaching the peak at 2:00 a.m, and then began to decrease, indicating that light regulate the synthesis of melatonin in plants. The expression profile of 5 melatonin synthesis genes was investigated by qRT-PCR, among them the mRNA transcript of PacSNAT, PacASMT and PacT5H2 increased and then decreased with time prolonging, in accordance with changes of melatonin content, indicating their key role in melatonin synthesis.

In order to explore the accumulation characteristics of melatonin in sweet cherry leaves, the melatonin content was measured every 4h for a whole day in mature leaves of 'Hongdeng' and the expression patterns of related synthetic genes were investigated. The melatonin content displayed double peaks at 14:00 and 22:00, respectively, speculating that high temperature and strong light intensity promote the synthesis of melatonin in leaves. In addition, expression pattern of 5 melatonin synthesis genes TDC, T5H1, T5H2, SNAT and ASMT were investigated by qRT-PCR. Among them, expression level of PacTDC, PacASMT, PacT5H1 and PacSNAT was positively related to the accumulation of melatonin. This study provides new information on melatonin synthesis in plants, especially in sweet cherry.

Grapes can be an abundant source for polyphenols. This work was to extend the investigation to white grape antioxidants by determining antioxidants and antioxidant activity (DPPH, ABTS and FRAP). The results suggested the polyphenols of ‘Italia’ was significantly higher than ‘Rosario Bianco’. But except FRAP, DPPH and ABTS were no difference between two withe cultivars. Moreover, the seeds of tested grape cultivars were the best source of antioxidants content and activity, followed by skins and then pulps of grapes.

Red grapes are a better source of antioxidants. Although studies have reported the major antioxidant contents and activities of grape cultivars, but the literature lacks information on detailed antioxidant composition and capacities of grape cultivars grown with rain-shelter-cultivation in Chengdu plain, south of China. In the present study, the total phenolics content (TPC), total flavonoids content (TFC), total flavanols content (TFAC), total anthocyanins content (TMAC) and antioxidant activity (DPPH, ABTS and FRAP) were detected and the results will provide basic knowledge about antioxidants of six red skin grapes. The results indicated the content rank order as follow: seeds > skin > pulp. Furthermore, ‘Red Globe’, ‘Jintianmeizhi’ and ‘Hongbaladuo’ have more antioxidants than other cultivars. Our results will provide a basic theory basis for consumers and further utilization of antioxidants.

The polyphenolic of grape skins, pulps and seeds are potential source of natural antioxidant, which are receiving increased attention. In the present work, the total phenolics content (TPC), total flavonoids content (TFC), total flavanols content (TFAC), total anthocyanins content (TMAC) and antioxidant activity (DPPH, ABTS and FRAP) in different tissues of 4 table grapes cultivated in Chengdu plain, south of China, were investigated. In present study, expect TMAC was not be detected in seeds, and our results showed that seeds were the highest in polyphenolic content and antioxidant activity followed by skins, and then pulp. Besides, ‘Fenghou’ is richer in polyphenolic content than other three cultivars. Hence, ‘Fenghou’ extracts possesses higher free radical scavenging ability.

To investigate the accumulation characteristics and mechanism of melatonin in cherry leaves of different leaf ages, the melatonin content and the expression of synthetic genes in cherry leaves of different leaf ages were measured. The results showed that the highest melatonin content was found in young leaves of cherry. By analyzing the expression of genes for melatonin synthesis in leaves of different leaf ages, it was found that there was a good correlation between gene expression and melatonin content, and the trend was similar, both young leaves were higher than mature leaves and old leaves. By measuring the melatonin content in cherry leaves and the expression of genes for melatonin synthesis, this paper revealed the accumulation rule of melatonin in cherry leaves, and provided a reference for studying the characteristics of melatonin accumulation in plant leaves.

A finite element fluid-solid coupling model for ocean energy harvester based on piezoelectric vortex-induced vibration(VIV) is established. Given that the Karman Vortex Street is generated after the fluid passes through the vibrator. The model includes the conversion of water flow energy to VIV energy and the capture of electrical energy by piezoelectric devices. And the output voltage curve is obtained by coupling with piezoelectric beam. Based on the fluid-solid coupling calculation, the dynamic response characteristics of the oscillator under different parameters such as shape of oscillators and fluid velocity are studied. The voltage output of piezoelectric beam in cylindrical, semi-cylindrical and regular triangular oscillators is analyzed. Simulation results show that the output voltage and pressure difference are largest in regular triangular oscillator system compared with the cylindrical and semi-cylindrical system. When changing fluid velocity, it is found that the higher the velocity of the water fluid be, the higher the output voltage be. When the given fluid velocity reaches 1 m/s, the maximum output voltage of cylindrical, semi-cylindrical and regular triangular piezoelectric energy harvesters reaches 0.045V, 0.08V, and 0.085V respectively. Under the same fluid velocity, change the ratio of height and width of oscillator, and find that the higher ratio of height and width of oscillator is more suitable to harvest the energy of VIV.

As a new interactive service technology, IPTV has been extensively studying in the field of TV pro-gram recommendation, but the sparse of the user-program rating matrix and the cold-start problem is a bottleneck that the program recommended accurately. In this paper, a flexible combination of two recommendation strategies proposed, which explored the sparse and cold-start problem as well as the issue of user interest change over time. This paper achieved content-based filtering section and collaborative filtering section according to the two combination strategies, which effectively solved the cold-start program and over the sparse problem and the problem of users interest change over time. The experimental results showed that this combinational recommendation system in optimal parameters compared by using any one of two combination strategies or not using any combination strategy at all, and the reducing range of MAE is [2.7%,3%].The increasing range of precision and recall is [13.8%95.5%] and [0,97.8%], respectively. The experiment showed better results when using combinational recommendation system in optimal parameters than using each combination strategies individually or not using any combination strategy.