To improve the accuracy of multi-step wind power forecast, a variational mode decomposition-long short-term memory (VMD-LSTM) forecast method is proposed. Firstly, the variational mode decomposition method is adopted to decompose the wind power data into three constituent modes, named as the long-term component, the fluctuation component and the random component. Secondly, long short-term memory network is utilised to deeply learn the characteristics of the three constituent modes. Profit from its unique forget gate and memory gate structure, the association with long-term time series is learned to build a multi-step forecast model. Finally, the wind power data from ELIA and NERL are used to test. The error analysis shows that the proposed method has superior performance in the multi-step forecast and real-time forecast.

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A comparison of the antitumor activity against two human tumor cell lines for the isomers of organometallo-substituted polyoxometalates is reported. The polyoxometalate skeletal isomers affect the antitumor activity. It is observed that the order of the antitumor activity of complexes is consistent with the order of the oxidation ability of polyanions among a couple of isomers possessing the same polyanion and organometallic group whether in the series of monosubstituted complexes or trisubstituted complexes as well in the sandwich compounds. INTRODUCTIONPolyoxometalates (POMs) are early transion metal oxygen anion clusters. Since the initial reports of the synthesis of [Ρν/"0 39 {Τ;(η 5 -ΰ 5 Η5)}] 4 " 20 years ago, the fields of organometallic derivatives of POMs has expanded significantly, and these derivatives now form a full class of compounds' 1 '. Organometallic derivatives of POMs are divided into POM-incorporated organometallic complexes, POM-supported organometallic complexes, and organometallic cation salts of polyoxometalates. This class of compounds has attracted much attention because of their variable applications, e.g. as industrial catalysts and as potential antitumor drugs. However, only a few papers involving the biological activity of POMs derivatized with organometallic groups has been reported ' 2 '. In order to develop the application of organo and organometalate polyoxocompounds in medicine, we systematically synthesized organotin, organotitanium, organozirconium and organophosphorus substituted POMs and investigated their antitumor activity |3 " 10 '. This paper reports a comparison of the antitumor activity of the skeletal isomers of organometallo substituted POMs possessing the same composition. It shows that the antitumor activity of the complexes is increasing with the oxidation ability of polyanions'"'. EXPERIMENTAL Physical measurementsΗ NMR spectra were recorded on a Bruker AC-80 spectrometer while 183 W and " 9 Sn NMR were recorded on a Unity-400 spectrometer. Polarograms and cyclic voltamograms were obtained using a BAS-100A electrochemical analyser. W, Si, Sn, Ge were determined by ICP emission spectrometry. The H2O content was determined by thermogravimetry. C, Ν and Η were determined by using a PE-2400 analyser. Κ was determined by atomic absorption spectroscopy. MaterialsThe compounds CH 3 COOCH 2 CH 2 SnCl 3 (C 4 H 7 0 2 SnCl3) and CH 3 COOCH(CH 3 )CH 2 SnCl 3 (C 5 H 9 0 2 SnCl 3 ) were prepared according to [12] while K 8 [a-SiW n 0 39 ]13H 2 0, Κ 8 [β 2 -SiW n 0 39 ]14H 2 0, a-NaioGeW 9 0 3 4-18H 2 0 and ß-Na 9 HGeW 9 0 34 -23H 2 0 were prepared following [13] and [14], respectively, and were identified by polarography. 2.3. Preparation of the complexes 2.3.1. α and ß 2 -K 3 H 2 [(CH 3 C00CH 2 CH 2 Sn)SiW,,0 39 ]nH 2 0 CH 3 COOCH 2 CH 2 SnCl 3 (0.3 lg, lmmol) was dissolved in H 2 0 40 mL, the pH of the solution being adjusted to 1.6 by potassium acetate, and lmmol of powdered α-Si Wn or ß 2 -SiWu was added bit by bit with stirring. The solution turned to clear within severa...

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This paper looks at the ability to cope with the uncertainty of wind power and reduce the impact of wind power forecast error (WPFE) on the operation and dispatch of power system. Therefore, several factors which are related to WPFE will be studied. By statistical analysis of the historical data, an indicator of real-time error based on these factors is obtained to estimate WPFE. Based on the real-time estimation of WPFE, a multi-time scale rolling dispatch model for wind/storage power system is established. In the real-time error compensation section of this model, the previous dispatch plan of thermal power unit is revised according to the estimation of WPFE. As the regulating capacity of thermal power unit within a short time period is limited, the estimation of WPFE is further compensated by using battery energy storage system. This can not only decrease the risk caused by the wind power uncertainty and lessen wind spillage, but also reduce the total cost. Thereby providing a new method to describe and model wind power uncertainty, and providing economic, safe and energy-saving dispatch plan for power system. The analysis in case study verifies the effectiveness of the proposed model.