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To achieve various conversion ratios with high power efficiency, a symmetrical digital selecting type switched-capacitor (SC) DC-DC converter with power saving techniques is proposed in this paper. Unlike conventional SC DC-DC converters, the voltage ratio of capacitors is expressed as the ratio of a power of two. By combining some of these capacitors in series, the proposed converter can achieve a larger number of conversion ratios than conventional converters. Furthermore, by employing a symmetrical structure with power saving techniques, the proposed converter can alleviate energy loss due to stray parasitic capacitance. The theoretical analysis and SPICE simulations show the effectiveness of the proposed converter.

Silicon steel magnesium oxide is a coating material used for preparing oriented silicon steel. In this paper, The preparation methods of silicon steel magnesium oxide and research progress of high quality silicon steel magnesium oxide preparation technology were introduced. The use of abundant brine resources in the preparation of silicon steel magnesium oxide was prospected.

In this paper we present a parallel robot with flexure hinges for target alignment system of a high power laser facility. The robot contains a parallel mechanism with 6 DOF which has nanometer positioning accuracy and is driven by six linear actuators. We design a new flexure hinge which has higher accuracy, strong environmental suitability and simple structure compared with conventional flexure hinge which has backlash and friction issues. The kinematics analysis of the parallel mechanism is also discussed. The simulation analysis of the mechanism is done by ADAMS. The mechanism is proved meeting the design requirements by comparing the results of the theory analysis and the simulations.

In trenchless detection of underground pipelines, a method has been introduced which employs Fiber Bragg Grating (FBG) sensors to detect curvatures of the pipeline at discrete points and reconstructs the spatial trajectory of the pipeline by means of a newly developed approach. In measuring the pipeline curvature, the FBG sensor may be twisted besides sustaining bending deformation. This paper proposes a new algorithm for curvature calculation at discrete points, considering both overall revolving and partial twisting of the FBG sensors in order to enhance the curve fitting accuracy. Simulation results verify the effectiveness of the method.

In this paper, we intend to design a force-feedback device that meets the requirements in workspace. First, based on the modified Delta mechanism, we introduced a chain offset angle that is defined as alpha. We established the positive and inverse kinematics model by the vector method. According to the inverse kinematics formula, envelope body equation of single-open-chain subspace was deduced. We drew the geometric shape of the subspace under three situations while L1 was more than or equal to or less than L2. Then the influence of alpha on the whole workspace and mechanism size is deeply discussed. The cross section view of the space was also plotted by MATLAB. Finally, we gave an example using the Jacobin matrix condition number as the mechanism performance index for dimensional synthesis. The results show that the workspace meets the requirements well.