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Large-scale wind power integration will increase the transmission channel flow and the network loss. Use of high-energy load to participate in wind power accommodation, will have a considerable impact on the network loss. This paper proposes several mathematical models in which high-energy load access power grid in different voltage levels and does a detailed analysis of the mechanism of high-energy load’s participation in the wind accommodation by layer. Based on that, combined with the actual structure of Hexi grid, the software PSASP is adopted to do detailed simulation analysis, so as to verify the correctness of the theoretical derivation.

Power transformer is a extensively-used electrical equipment in our national economy. Generally speaking, there exists 6~8 times of transformation from electricity generation, power supply to power utilization. As is known to all, transformer itself generates power loss, so, because there are so many transformers and the whole capacity is very big, the economic operation of transformers proves of great importance. This article finds effective energy-saving method by analyzing a mode of busbar-line transformer economic operation. In the end, a practical case is added to prove the correctness and validity of this mode.

TCP Vegas has the problem that it stops slow start too early, and it is more obvious in the large delay-bandwidth network. This phenomenon can cause a very long linear growth after entering congestion avoidance phase, and it will reduce the transmission efficiency. This paper analyzes that the reasons for this phenomenon is due to the exponential growth of slow start itself, then puts forward a dynamic growth algorithms of slow start, we call it Vegas-f. Improved algorithms can dynamically adjust the growth rate of slow start, so as to improve the transmission efficiency and competitiveness in mixing network. Simulation results show that the improved algorithm has completely solved the problem and the performance is improved significantly.

This article studied the dehydration effect of elutriation sludge produced in the process of cultivating aerobic granular sludge, which is a joint regulation of cationic polyacrylamide (CPAM) and modified coal fly ash, using sludge specific resistance(SRF) and moisture content of sludge extent as the target. The results show that the greater the relative molecular weight, the better effect is. CPAM whose relative molecular weight is 8 million is the best type when solo casted. When casted by15 mg/L, SRF is reduced to 0.43×108 S2/g, The 1 g/L coal fly ash and 15 mg/L 8 million CPAM joint control, SRF is reduced to 0.4×108 S2/g, moisture content is 72.04%. When using modified coal fly ash, the result is better. Modified coal fly ash can effectively promote the efficiency of CPAM as the coagulant aid. It can further reduce SRF and moisture content of the sludge. We can observe the effects modified coal fly ash joint CPAM has on elutriation sludge morphology by scanning electron microscopy (SEM).

The paper was mainly research on hydraulic support by finite elements method. It took a certainly type of hydraulic powered support as an example. All parts of hydraulic support were analyzed in finite element analysis software Ansys Workbench12.1. The simulation data was compared with test data and the relative error factor was discussed, it indicated that three-way pasting the strain foil could generate much more low relative error than other ways or pasting foils in pressure frame test.

The key technologies of CAD/CAM integration of mechanical parts which include parametric modeling technology, model transformation of CAD/CAE and finite element modeling were studied. Based on redevelopment of UG, the process of parametric modeling about typical part was achieved. The identification, selection, extraction, and removal of the details in the CAD model were analyzed. The extraction approach of the mid-surface in the dimensional reduction of the CAD model was executed. The CAD/CAE integration system of the design and finite element analysis for mechanical parts was established by the redevelopment of UG and ANSYS with Visual C++, UG/Open and APDL as tools. The parametric design and automatic finite element analysis for mechanical parts were implemented.