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As for the pulp-mixing process of small mineral, its flow field configuration principle is to obtain effective cycle in the same operating condition, and allocate strong shearing action according to the needs. This paper takes the coupling of secondary circulating flow pattern as the basis of flow field design to construct the double-impeller function system with the common effects of axial flow impeller and radial flow impeller, thus forming the high-efficient functional mechanism merging strong cycle and strong shearing together. It shows in the result that the effect of double-impeller configuration is strengthened compared to the conventional single-impeller pulp-mixing process: the decrease range of mixing time can reach about 50%; shearing mechanism has effectively blended in the related flow field, and achieved improvement on this basis. It means that the double-impeller configuration has respectively made up the shortage of the cycle performance in the single-impeller radial flow field and the shearing performance in the single-impeller axial flow field, initially formed the mixing mechanism characterized by high-efficient strong cycle mixing and high shearing mixing, and provided practical foundation to develop new and high-efficient modified pulp-mixing equipment.

In this paper, dynamic instability behavior of a linear viscoelastic panel in supersonic flow is investigated. The quasi-steady piston theory of supersonic flow is employed for the aerodynamic pressure. The partial differential governing equation of isotropic flat panel is derived by introducing viscoelastic structural damping based on Kelvins model. The panel governing equation is transformed into a set of ordinary differential equations via the Galerkin approach. First-order state equations are afterwards obtained and solved by means of a standard eigenvalue calculation. The dynamic instability of viscoelstic panels is predicted by the feature of characteristic roots. The phenomena of coupled-mode flutter without structural damping and single-mode flutter with structural damping induced by the supersonic flow are observed for the different dynamic pressure values. Results indicate that structural damping plays an important role for the stability of panels flutter. Flutter threshold keeps decreasing as viscoelastic structural damping is increased.

As an important step of printed formula recognition system, formula extraction locates the formula fields on the layout images of printed documents, which influences the performance of formula recognition to a great extent. However, the errors of automatic formula extraction occur inevitably because of the complexity of formulas themselves and the layouts which the formulas situated. To solve this problem, this paper designed a post-processing method to correct the errors existing in the results of formula extraction algorithm according to relative layout knowledge. First of all, the geometrical features of various layout fields were employed to correct the extraction errors. Then, the syntax rules were used to check the boundary components of different kinds of areas in layouts to identify which field it should belong to. Finally, the formula area was adjusted according to above mentioned information.

The main approach to obtain nanomaterial is nanospinning technology at present. Due to the inherent characteristics of nanomaterial itself, which are easily affected by the electric field force effect of spinning. And for the spinning machine nozzle electric field is relatively complex, so nanospinning products at present, is easily affected by the electric field force and dissipated. So, the nanospinning collection efficiency is low. This paper adopts an oval enhanced electrostatic mechanism, method of using additional electric field to improve the balance obtained nanomaterial collection rate. And the construct high voltage electrostatic spinning machine virtual prototype,complete the analysis of the improved method of static electric field. The analysis results indicate that the electric field can effectively improve the collection rate of nanospinning. Through the study of the additional electric field strength further size on the electric field force and the ellipse, can more effectively improve the collection rate of nanospinning products.

Optical stimulation of the inner ear, the cochlea, has been proved as a possible alternative to conventional cochlear implant with the hypothetical improvement of dynamic range and frequency resolution. Moreover, the laser has good directionality character and optical signal between adjacent fibers do not readily interfere. Therefore, cochlear implant based on optical stimulation is promising for further exploration and development. The design of an experimental system for optical stimulation of the cochlea is introduced in this paper. For the important part, the selection of NIR laser and the optical signal control methods were discussed. The pulsed laser light was coupled by fiber or fiber array and radiated to the cochlea. For each channel laser pulse, the width modulation was varied from 10us to 1ms, the pulse repetition rate from 5 Hz to 10 KHz, single pulse energy from 0 to 3.6mJ. The application of high precision DAC made the resolution of the pulse energy regulation up to 1uJ/div. The experiment results show that this design and implementation can meet the requirements on further optical stimulation of the cochlea research.

With recent development of technology and management in power market and equipment, more and more distributed generation (DG) is embedded in the distribution network. However the approach of connecting DG in most cases is based on a so-called ‘fit and forget’ policy and the capacity of DG is limited rigidly by distribution system operator to avoid the negative effects of high level penetration. New management technologies have been proposed to handle the integration of DGs in the distribution networks. In this review, the micro grid (MG) was treated as the local control method to coordinate DGs within a small area of distribution network. And the active distribution network (AND) was treated as the global control mechanism to actively manage DGs, MGs and other equipment. The operation framework of ADN was firstly introduced. Then based on the static and dynamic models of DGs and MGs, impacts of DGs and MGs on the ADN are surveyed from power quality, stability to the operation. Finally, the conclusion and suggestion is given in this paper.

Using field experiments, the vibration effects of historic tower induced by planed railway line are estimated. The vibrations include the construction vibration and the traffic-induced vibration. The results show that the blasting construction leads to the significant increase in vertical velocity and acceleration. There is no difference between the background vibration of field and foundation of tower. Different types of the sites soil around the tower cause little change. Each measurement time showed an upward trend of vibration level with the increase of frequency. The closer the tower is to the vibration source, the larger the structural vibrations would be. The dominant frequency range for highway-induced vibration is 10-20Hz. For train-induced vibration, the dominant frequency range is more than 40Hz. Surface waves will result in amplification phenomenon of vibration velocity of ancient structures within a certain range.

In view of the problems existing in the blended learning model, this paper presents a mobile blended learning system using mobile and wireless communication technology and context-aware Technology, and discusses the structure, functions and key technologies of the system. This system can get information about learning to use context-aware function, so as to provide adaptive learning contents and service in an intelligent way for learners.

It is an innovative work to make the electromagnetic damper with strong magnetic material. Firstly, the structural research and the experimental research on the basic performance of electromagnetic damper have been made. Then the theoretical research is conducted based on the above research results. Thus, the paper put forward and deduced the electromagnetic damper restoring force model and the motion parameter’s effects on its performance. Such as vibration frequency and amplitude are also studied in the paper. The results showed that the new electromagnetic damper is characteristic of simple structure and good performance and that the theoretical model coincides well with the results obtained from the experiments. Keywords：strong magnetic material, electromagnetic damper restoring force model, vibration frequency, motion amplitude value.

A highly heat-dissipating and high-voltage SOI-LDMOS power device is proposed. Its substrate was selectively etched, like the Camsemi SOI, so breakdown voltage was decided only by lateral breakdown voltage. A p-type layer and a Si3N4 buried layers were introduced into the new structure for lowering specific on-resistance and temperature. The simulation results show that breakdown voltage is 747 V at the 37 μm length of the drift region, and specific on-resistance and maximum surface temperature are reduced by 94.48% and 15.43% than those of Camsemi SOI, respectively.