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Based on the prototype of No. 2307 filling working face in Yuyang mine, using the method of similar simulation combined with numerical simulation, the geological mechanics model is established to simulate and analyze the mechanics evolution law and the deformation and movement process of the surrounding rock and the surface during the filling mining. Research shows that backfilling can effectively control surrounding rock failure and the surface deformation, and the roof doesn’t collapse, but the bed separated fissures appear, and the maximum stagnation lags the working face by 58.5m; in the mining, surrounding rock stress releases and roof stretches, and the stress concentration appears in the front and end of the goaf, which is 1.47~1.78 times larger than that before mining, and the periodic weighting of filling working face is not obvious; the subsidence value is 212.7 mm after excavation, with the factor 0.06, and the ground level deformation and slope deformation shape are similar to the curve shape of roof caving control method with small values. The results have important theoretical guiding significance for controlling surface movement deformation in actual filling mining.

In the process of open-pit mine stripping,the surface and slop that influenced by open-pit mining stripping, rock mass structure and lithology, blasting vibration, slope angle, groundwater and precipitation start to move and deform,which threatens the safe use of industrial and civil buildings adjacent to the open pit mining .In this paper, through the establishment of increasing the momentum of adaptive BP neural network,with the aid of existing sample data,we carried out on the network training, testing, and compared with the target, its precision is higher.The result showed that network is effective and reliable,and the trained network is applied to the observation point prediction,so we get the value of its settlement deformation in 2013.The method is expected to have the important meaning on the multi-factor coupling surface subsidence .

In order to solve the coupling of rotor current of d axis and q axis, a new kind of control scheme for double-fed induction machine (DFIM) speed regulation system is proposed based on the theory of auto disturbance rejection controller (ADRC). The ADRC is composed of three parts: tracking-differentiator (TD), extended state observer (ESO) and nonlinear state feedback controller (NSFC). In the ADRC scheme, the coupling of rotor current is regarded as the inner disturbance of DFIM, inputting this disturbance to the input port of the speed regulation system by the feedforward compensation, the speed regulation system can change to the simple integral series connection system or simple linear system. This controller can realize decoupling of rotor current of d axis and q axis, obtaining a good speed tracking performance with small overshoot and fast setting time. Simulation results indicate the rationality and validity of the ADRC.

With the water tourism developed, making the development of water landscape rising rapidly. How to ensure the safety of hydraulic engineering technology under normal circumstances, and protect the ecological environment, play tourism economic benefits are an important problem in landscape design. Under the premise of following the principle of water conservancy landscape planning and design, applying AHP to research Xiya ditch waterfall landscape and optimize design program, then set up the preferred plan from ecological effect, waterfalls and technological factors three aspects of evaluation index. This provides theory basis for model test and engineering implementation in Xiya ditch waterfall landscape. In recent years, water conservancy projects relying on water industry form a large number of humanities landscape, natural landscape. The development of water tourism, gradually achieved a certain economic, social and environmental benefits. Giving full play to the comprehensive benefits of water conservancy projects, Ministry of Water Resources has granted water tourism as three major elements in water economy with water supply, power generation.

Application of doubly-fed variable speed system in motor-generator station is a new field in marine. This paper introduced the theory of doubly-fed variable speed and the design of doubly-fed system, adopted stator flux orientation vector control in induction motor by rotor current control with inverter. A kind of simple and fast starting device was designed, thus the power demand of inverter was reduced greatly. Experiment results showed that doubly-fed induction machine was good for speed adjusting and transient speed change rate was smaller than 1%.

This study was focused on the theoretical analysis and experimental investigations about the frictional wear of nanometric zirconia dental ceramics. An MRH-3 digital-display high-speed ring-on-block tribometer was used for frictional wear experiments. A PGI800 coarseness profiling instrument was used to test the width and the length of the grinding defects on specimen surfaces. An S-3500N SEM was employed in the microscopic observation of the surface morphology after the abrasion. Results indicated that the frictional factor and the wear rate of nanometric ZrO2 ceramics decreased significantly under identical working and frictional conditions compared with ZrO2. The wear mechanism of nanometric ZrO2 ceramics was micromachining and plastic deformation while the wearing mechanism of ZrO2 ceramics was brittle fracture and abrasive wear.