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Proposed general distribution power flow algorithm based on the current network equation. The power flow equations of the algorithm based on the node current balance, and the Jacobian matrix is a constant coefficient matrix compared to the conventional Newton method. It has the characteristics of easy programming, and the method has universality at the same time. It can be used for radial distribution network and systems with loops. The example shows that the method is superior to conventional Newton method on speed and convergence.

Oxidation of organic phosphorus pesticides wastewater (OPPs-MW) was studied in a batch-reactor under the supercritical oxidizing water condition. The temperature, pressure and coefficient of oxidation were investigated as influence factor for COD removal efficiency by response surface methodology. Temperature is the most significant factor in treatment OPPs-MW and a good fitting polynomial equation obtained. Organic acid would generate under incomplete decomposition condition and NH3-N could hardly decompose effectively when temperature below 600°C

Silica fillers are well known to improve the mechanical properties of elastomers.Nevertheless, the silica filler particles tend to aggregate and affect the properties of the elastomer. In the present study, the silica filler was modified by silane coupling agent (A-151) in order to improve the dispersion of the filler in silicone rubber. The composites samples added with surface treated silica filler was characterized by FT-IR, bound rubber, and fluorescent microscope with that reinforced by the unmodified filler as a comparison. FT-IR results evidences the successful surface modified by silane coupling agent. Bound rubber contents of the origin silica filler are much lower than that of the silica filler with the silane coupling agent treatment. The modified silica-filled shows a better dispersion than that of the origin silica filler and the agglomeration of filler occurs in the unmodified silica-filler compounds.

In order to overcome the inefficiency shortcoming of traditional step-based searching method for extremum seeking in two-dimensional fractional Fourier domain, some typical intelligent optimization methods such as genetic algorithms, continuous ant colony algorithm, particle swarm optimization and chaos optimization method are introduced and applied successfully in fractional Fourier transform. The performances of the global optimization methods are compared with step-based method based on simulation. Results show that the COA optimization algorithm is much more preferable considering computation efficiency, precision and resolution in all the above mentioned optimization methods

To satisfy the demand of inlet pressure for air powered engine, it is necessarily to design control valve. The design idea of control valve was proposed, and the models for simulation design were established. These models are air bottle state model, open area model of control valve, spool dynamic model and shape calculation model of characteristic vent. Based on these models, the joint simulation and the experiment test have been done. The result shows that the designed control valve can provide required inlet pressure for air powered engine and satisfy the work demand well. The result of the experiment verifies the rationality and validity of the simulation design, and the method can be used in the design of the congener valve.

Parallel computation is an effective approach to real-time simulation and transient stability online assessment of large-scale power systems. In this paper, the s-stage 2s-order symplectic Runge-Kutta-Nyström method is adopted for transient stability simulation of power system using classic model. Using Butcher transformation, a new parallel algorithm has been derived. The proposed algorithm has the convergence characteristic of a Newton type method and is of fully parallel-in-time. Through numerical simulation where the IEEE 145-bus power system is used, the proposed algorithm has been tested and compared with the conventional parallel-in-time Newton approach using implicit trapezoidal rule.

The symplectic algorithm is a kind of new numerical integration methods. This paper proposes the application of the explicit and symplectic Runge-Kutta-Nyström method to solve the differential equations encountered in the power system transient stability simulation. The proposed method achieves significant improvement both in speed and in calculation precision as compared to the conventional Runge-Kutta method which is widely used for power system transient stability simulation. The proposed method is applied to the IEEE 145-bus system and the results are reported.

It is well-known that, the identification of the single-phase to ground faulted line in neutral non-grounded distribution systems is a difficult problem, due to its very small faulted current. This paper proposes a new method for the solution of this problem. The principle of the proposed method is to convert the neutral non-grounded system into a neutral grounded system temporarily by using a triggered vacuum switch based controllable short-circuit equipment. By time-domain numerical simulation, the proposed method is evaluated, and the simulation results have shown the effectiveness of the proposed method.

430 stainless steel is used as raw material and pickling in HCl-based electrolytes is adopted, and the effect of oxidation agent on removal behavior of the oxide layer on stainless steel is systematically studied; study found that the oxide layer of stainless steel after heat treatment in the lab is composed of iron oxide and chromium oxide, and outer oxide layer has dense structure while inner layer has multihole structure; with the increasing oxidation agent addition, corrosion potential of stainless steel after heat treatment increased; under 1.0% oxidation agent addtion condition, only few inner oxide remained and removal tendency of oxide layer is obvious when pickled for 200s; oxide on surface totally got removed, and a smooth surface obtained after pickled for 400s.

Both total potential energy and buckling equation of two-span continuous beam with lateral elastic brace under uniform load are deduced, based on energy variation method and the principle of minimum potential energy. Buckling of H-beams is simulated by ANSYS software, then compared to theoretical value, validated its rationality. High precision buckling moment formula is regressed using 1stOpt which is a famous mathematical optimization analysis software in China. The relationship between lateral brace stiffness and buckling moment is obtained. Results: with lateral brace stiffness increases, critical bending moment of beam increases within up-limit, e.g. when lateral brace stiffness increases to certain extent, buckling moment no longer increases.