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The objective of this study was to explore from a theoretical perspective the relationship between dry mode shapes and the distortions associated with wet mode shapes. This study investigated the free vibration characteristics of a rectangular thin plate partially coupled with fluid. A powerful full-field experimental technique referred to as AF-ESPI was used to measure vibration modes and the corresponding resonant frequencies. The derivation of wet mode shapes from dry mode shapes proved effective in analyzing problems for plate-fluid interactions. Our analysis revealed that every wet mode shape is composed of multiple dry mode shapes with corresponding contribution coefficients. In the proposed analytic approach, the superposition method is used to deal with theoretical aspects of thin plate vibration behavior, and velocity potential is used to express the dynamic behavior of an incompressible flow field in a finite container. The accuracy of the results obtained using the proposed theoretical approach was verified via comparison with numerical results obtained using finite element method (FEM) and experimental measurements. A detailed discussion pertaining to the relationship between wet and dry mode shapes is also presented.

Emodinol, 1β,3β,23-trihydroxyolean-12-en-28-acid, as the main active ingredient firstly extracted from the rhizomes of Elaeagus pungens by our research group, has been demonstrated to exhibit uricosuric activity by our previous study. The aim of this study was to evaluate the uricosuric and nephroprotective effects of emodinol and explore its possible mechanisms in potassium oxonate-induced hyperuricemic mice with renal dysfunction. Mice were orally administrated 250 mg/kg of potassium oxonate once daily for 7 consecutive days to induce hyperuricemia with renal dysfunction. Emodinol was given at doses of 25, 50, and 100 mg/kg on the same day 1 h after oxonate treatment, and allopurinol (10 mg/kg) was given as a positive control. After 1 week, serum uric acid, serum creatinine, urine uric acid, urine creatinine, blood urea nitrogen, and hepatic xanthine oxidase activity were determined. The mRNA and protein levels of urate transporter 1, glucose transporter 9, ATP-binding cassette subfamily G member 2, organic anion transporter 1, oncoprotein-induced transcript 3, and organic cation/carnitine transporters in the kidney were detected by real-time polymerase chain reaction and Western blot analysis. In addition, urinary and renal Tamm-Horsfall glycoprotein concentrations were examined by ELISA assays. Emodinol significantly reduced serum urate levels, increased urinary urate levels and fractional excretion of uric acid, and inhibited hepatic xanthine oxidase activity in hyperuricemic mice. Moreover, potassium oxonate administration led to dys expressions of renal urate transporter 1, glucose transporter 9, ATP-binding cassette subfamily G member 2, organic anion transporter 1, and oncoprotein-induced transcript 3 as well as alternations of uromodulin concentrations, which could be reversed by emodinol. On the other hand, treatment of emodinol caused upregulated expressions of organic cation/carnitine transporters, resulting in an improvement of renal function characterized by decreased serum creatinine and blood urea nitrogen levels. Emodinol exhibited hypouricemic and nephroprotective actions by inhibiting xanthine oxidase activity and regulating renal ion transporters and oncoprotein-induced transcript 3, which may be a potential therapeutic agent in hyperuricemia and renal dysfunction.

Voltage sag is one of the most serious dynamic power quality problems which influences normal and safe operation of many electric equipments. In order to measure characteristic parameters (magnitude, duration and phase-angle jump) of voltage sag accurately, a method of voltage sag detection based on dq transform and mathematical morphology filter is present. Firstly, a fictitious three-phase system is created from a reference single-phase voltage by a 60°delay. And then the abc three-phase voltages are transformed into the dq conversion of instantaneous voltages. The direct current components of dq instantaneous voltages are picked up by mathematical morphology filter. Subsequently the magnitude, duration and phase-angle jump of voltage sag are calculated. Compared with the conventional low pass filter and average voltage method, the simulation results verify that the mathematical morphology filter method has shorter response time and slightly higher detection accuracy.

In full knowledge of the energy-saving and emission reduction (ESAER) policies in China, it is analyzed in this paper what the promising new futures in electricity demand in East China in the context of ESAER. To propose the well applicable load forecasting methods for East China power grid, where the ESAER policies have being intensively implemented since 2005, the reality of economic development and industrialization in East China are also discussed. Therefore the well-used long-term forecasting methods are analyzed detailed for their respective applicability under the background of ESAER. Furthermore, in order to take the influence of ESAER policies into account in the forecasting models, the "improved Solow forecasting method" is proposed in this paper. Then these methods are used to forecast the electricity demand from the year 2009 to the year 2015 for East China power grid to check their feasibility. Finally, the forecasting results of electricity demand in East China are analyzed and compared.