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The purpose of particles impact drilling is to increase the rate of penetration when drilling extra-hard and strong-abrasive rocks, where supposed to be time-consuming and costly. Now the technology becomes the world’s most potential drilling technology for deep wells and ultra-deep well. The most important part of the drilling technology is the nozzle which accelerate the particles. The paper introduces the basic four types of the nozzles, and researches the acceleration effect of nozzles based on FLUENT. By concluding the simulation, put up a new structure of nozzle, and simulates the acceleration of the particle of different drilling fluid and particles inlet velocities, discusses how the length of accelerating cavity affect the acceleration.

The real-timely estimation of the SOC (state of charge) is the key technology in Li-ion battery management system. In this paper, to overcome the error of the SOC estimation of Extended Kalman filter (EKF), a new estimation method based on modified-strong tracking filter (MSTF) is applied to SOC estimation of Li-ion battery, based on the second-order RC equivalent circuit model. Experiments are made to compare the new filter with the EKF and Coulomb counting approach (Ah). The simulation results demonstrate that the new filter algorithm MSTF used in this paper has higher filtering accuracy under the same conditions.

RE nanophase composite material between the grain size 30nm and 100nm are prepared by the method of mechano-chemistry，in which the material’s adsorptive capacity to metal base is checked，and the nature of anti-friction as well as self-repairing effectiveness to the surface of abrasion is tested by four-ball friction wear testing machine. The results show that RE nanophase composite material prepared by the method of mechano-chemistry has a good adsorptive capacity to metal base，and the wear surface can be covered and repaired under dynamic condition；RE nanophase composite material used as anti-friction material is test and verified.

In this paper, a method of detecting adult images based on AdaBoost was proposed. We focused on the detection of the adult images that have naked breasts or naked genitalia. By using basic and rotated Haar-like features extracted from the samples in the training set, we trained a cascade detector. The detector would classify the image whether to be a pornographic one or not. The results showed that this method achieved a high detection rate and a low false alarm rate.

This paper describes a nonlinear adaptive dynamic inversion controller for a flexible air-breathing hypersonic vehicle model. The complete characterization of the nonlinear internal dynamic of the Bolender and Doman model with respect to velocity，altitude and angle as the regulated outputs is considered in this paper. The derivation of the internal dynamics presented in this work is comprehensive of the flexible dynamics. For the purpose of control design，we decompose the equations of motion into functional subsystems，namely，the velocity subsystem，the altitude and flight-path angle subsystem，and the angle of attack and pitch rate subsystem. Each subsystem is controlled separately using available inputs and intermediate virtual control commands. The adaptive fuzzy system is then developed to identify the uncertain in the model parameters. Simulation results are provided to demonstrate the robustness and the efficacy of the proposed controller

In this paper, an Improved Nonsingular Terminal Sliding-mode (INTSM) observer is proposed to estimate the speed of the permanent magnet synchronous motor (PMSM). The Nonsingular Terminal Sliding-mode (NTSM) not only inherits the good performance to track the state error, but also has the characteristic of limited time convergence. However, the conventional NTSM control law is too complex to apply in practice. The INTSM takes the thoughts of the fast Terminal Sliding-mode and uses a new nonlinear term to replace the conventional term. As a result, the new observer owns the characteristics of global fast convergence and simple control law. At last, the proposed method proves to be effective through the theoretical analysis and simulation test.

Electricity transformer is an important, widely used electrical equipment. Current the iron beam sectional of the electricity transformer is based on experienced standards which can not achieve the best economic benefits. According to practical technology, we build a basic optimization model about multistep iron beam section. And we also give a reasonable design on the tolerance zone between the diameter of iron beam sectional circumcircle and the diameter of the winding steel-flue, as well as the arrangement about the oil path in the iron beam, which has a big realistic significance and application value. We come up with five reasonable model assumptions to simplified the problem, turning the tolerance zone design problem into the function extreme one. We adopt "Ideal assumption first, specific modification second" method on designing the oil path, considering all kinds of situations to obtain optimization. The core algorithm is dynamic programming which is much faster, much more stable than using Lingo. All the solving and analyzing on math models are based on C++ programming language.

An adaptive model reference parameter identification method without sensors for PMSM is presented in this paper and this method is based on double manifold sliding mode. The real model of PMSM is selected as the reference model and the d/q frame observer which is constructed using current model of the motor is selected as the adjustable model. The manifold sliding mode surface is constructed using the output (current in d/q frame) errors of the two models. Proper parameters are selected to guarantee the stability of the observer. The adjustable model converges to the reference model and the running state of motor can be identified. Theoretical analysis and simulation results show that the proposed strategy has high static and dynamic performance，high tracking precision as well as stronger robustness.

In Section 1, we describe process of ball-bat collision using kinetic model, and derive the post-collision ball speed as a function of the hitting location. Then we differentiate the function and find out where the sweet spot is. The result successfully explains the best location is not at the end of the bat in consistent with our practical experience. In Section 2, based on the model in Section 1, we add two assumptions, supposing corking only influences mass and moment of inertia of bat. Then the maximum outgoing ball speed is only depended on mass of bat. The result shows properly corking will enhance the bat performance. In Section 3, we explain “trampoline effect” in dynamic model and throw light on energy transformation in collision process. We conclude that COR is related to materials, and aluminum bats perform better than wood bats.