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A 3.3 kV rated Si-SiC hybrid IGBT with Si-based active structure and Si/SiC composite junction edge termination is proposed in this paper. A single deep and wide Si trench, capped with a hetero-epitaxially grown SiC layer, is employed as the edge termination structure. Therefore, the active region can make full use of the mature Si-based IGBT processes and cell structures with high carrier channel mobility and long electron-hole lifetime. Meanwhile the edge termination benefits from the high critical electric field of SiC and its breakdown voltage can easily reach the ideal value with excellent process windows. The ruggedness and reliability of the device can also be significantly improved because the avalanche occurs inside the silicon bulk and is far from the dielectric/semiconductor interface. The excellent characteristics of the edge termination are studied in detail by simulation. It is shown that the proposed edge structure has higher reliability in terms of the hot carrier effects and much less sensitivity to the interface charges in terms of breakdown degradation.

The reliability index of powerplant was allocated with the score allocation method. Based on the unit reliability growth test, the DYANE model was used to analyze the reliability growth trend of the ignition system. With the dual ignition system, the reliability of the ignition portion and the safe reliability of the powerplant were improved.

The necessary condition for power devices with enough blocking properties is Junction termination technology. In this paper, starting with the dose of rings, 3.3 kV Floating Filed Rings was investigated, and the influence of electric field and current density on the breakdown characteristic is also described. The results show that the dose of field rings directly affects the stability of breakdown voltage, this impact is relevant to the location of the peak electric field and the peak current density when breakdown was occurred. When the peak electric field appears in the middle of the field rings, the breakdown voltage is not sensitive to the dose of rings; however, when the peak electric field and strongest current density appeared on the edge of termination at the same time, breakdown voltage become very sensitive to the dose of rings because of the highest impact ionization in this position. Simulations and experiments indicate that the junction termination has better withstand voltage stability , when electric field distributes uniformly, the position of breakdown is in the middle of the termination, and the strongest current density appears in the main junction.

The finite element model of an aircraft hydraulic pipe was established in this paper. Based on LS-Dyna software equivalent static pressure and peak pressure surface loads on the tire burst test (main landing gear retracted state, and did not consider the impact of tire debris) jets were applied to the hydraulic pipe. Both stress and strain contours of hydraulic pipe were obtained under dynamic loading. Plastic strain occurred under both loads on the hydraulic pipe, and the peak pulse loads were more severe than equivalent static loads, the maximum strain reached 0.41172 under the peak pulse loads. However, in both cases the pipe is not broken.

A new protective material-steel mesh reinforced concrete was developed under the condition of modern high-tech weapon development. The comparative tests were conducted with steel fiber reinforced and steel reinforced concrete. The enhancement characteristics of three composites were analyzed in the respects of base material, the distribution of reinforced material and its bonding. The results indicate that steel mesh reinforced concrete is the most effective composite resisting penetration.

This paper introduced the method that developed model and frequency analyses of powertrain mounting system based on ADAMS (Automatic Dynamic Analysis of Mechanical Systems ). The six vibration frequencies and its corresponding modes were obtained and compared with experimental results. Mount stiffness of the four mounting parts were optimized to use Adams/Insight. The former low decoupling degrees and the new part stiffness were observed to improve the disadvantage and can reduce the vibration transfer.

This paper comprehensively uses a combination of methods of theoretical analysis, numerical simulation as well as the model test to do the structural analysis to some type of the passenger cabin doors, so as to set up the model for the descriptions of the part subjected to explosion impact loading; Through the tests, we gets the explosion impact loading and other important physical parameters. Aimed at the material of the door as well as the simplified models subjected to the explosion impact loading, the numerical simulation is put up by the finite element software ABAQUS. The necessity of the reinforcement is deeply analyzed as well as the difficulties during the process of the reinforcement, furthermore, the reinforcement measures are proposed to the airliner door. Keywords: Numerical simulation; Explosion impact loading; Explosion-combustion power equipments

For a mini remotely operated vehicle (mini-ROV), the performance of the propulsion system has a direct impact on its underwater running and operation. A proper designed propulsion module will improve the maneuverability and controllablity of the mini ROV. In this paper, we propose a kind of propulsion modular series taking lower drag, higher efficiency and lighter weight as design objectives. Simulation and experiment results are also presented to illustrate performance of a specific designed thruster.

We studied the high frequency vibrator of the top drive system based on ADAMS. A parameterized simulation model of the axial rotation of gears and eccentric block is established, and dynamic change of the impact and the actual movement of the rotating components of the top drive system are analyzed. Then create a virtual prototype on the basis of that. It can obtain curves that some parameters change relative to time, such as the exciting force and the centroid position of eccentric block. Thus it achieves dynamic simulation analysis of virtual prototype of the top drive system.

Hammer is an important part of the top drive system. ANSYS software was applied to analyze the top drive system drilling rig hammer. The procedures and methods were introduced in this paper. A reliable reference for optimizing the design and improving the structure is provided. Through calculation, whether the design of top drive system is sufficient to actual requirement can be judged. The changes of strain and stress in hammer are qualified to the top drive system.

To meet the air emergency evacuation needs of aircraft flight test team members, we developed the air emergency opening system of aircraft service port. During the flight tests, the probability of false triggering of the electro-explosive system used in the emergency opening system is called for not more than 0.001 in the confidence of not less than 90% under the interference of external electromagnetic radiation, and when the aircraft experience an emergency, the electro-explosive system can work reliably according to the preestablished instructions to detonate the detonation power unit of the emergency opening system, and the service port will be pushed into the cabin fast and accurately, so that the aircrew could bail out of the aircraft by the barrier-free access. Therefore, this paper examines the electromagnetic radiation environment of the inner and outer fuselage of the aircraft, and then analyzes the hazard of the electromagnetic environment to the electro-explosive system of the emergency opening system as a base for the safety design of the anti-electromagnetic radiation of the emergency opening system.

The crew emergency evacuation security system is a life-saving device, the ultimate function of which is to save the life of the aircraft crew in a new regional airliner at high altitude. The system is used to push the service door with translational motion for a suitable distance. Before the system was started, the force state of the service door was got with the fluid mechanics knowledge. When the system was started, after a period of pressure relief time, the aircraft cabin pressure was calculated with the Bernoulli's Equation. The movement trajectory and the force state of the service door were obtained by the computational fluid dynamics theory and numerical simulation method. All of the above work must lay a theoretical foundation for the development of the crew emergency evacuation security system, and ensure the flight safety.

The purpose of the present study was to explore the self-learning experiences of depression patients on interactive multimedia education program. Qualitative in-depth interviews were employed. Fourteen patients with a first episode of major depression were recruited from a psychiatric outpatient department. Explanations of the purposes of the exercise and on-the-spot teaching were provided by the researcher before the study began. A tape-recorded, semi-structured interview format was employed after two weeks. Data analysis was performed in the framework of line-by-line content, contextual and thematic analysis. Eight subjects successfully completed the entire learning activities. Content analysis revealed 4 main aspects of successful self-learning experiences: the triggering of learning motivation, the enjoyment of self-paced learning, support for the effects of learning materials, and the gaining of self- awareness and changes. The factors influencing learning performance were related to: environmental impact, the degree of familiarity with traditional learning, possession or non-possession of the necessary computer operation skills, and good computer support. However, the findings provide a preliminary understanding of the application of interactive multimedia education programs in terms of self-learning outcomes and recognizing key elements of learning impediments among the study sample. A larger sample size with different clinical contexts is recommended to determine the effect and generalizability for future research. Furthermore, the creation of a computerized learning environment with different educational styles is crucial to patients' success in obtaining depression-related information and understanding effective adaptive skills.

The combined use of batifiban, a synthetic platelet GPII b/ IIIa receptor antagonist, and antithrombin agents is an attractive option for the treatment of patients with non-ST-segment elevation (NSTE) acute coronary syndrome (ACS) and those scheduled for percutaneous coronary intervention. To observe whether antithrombin agents affect the pharmacokinetic and pharmacodynamic properties of batifiban in combination therapy and optimize clinical administration dosage of batifiban, an open-label and parallel study was conducted. Thirty healthy subjects were randomly divided into three groups, which were sequentially treated with batifiban alone, or oral coadministration of clopidogrel, aspirin and UFH, or batifiban coadministered with these antithrombin agents. Blood samples were collected at pre-specified time points. The evaluation index included the inhibition of platelet aggregation and pharmacokinetic parameters. The pharmacokinetic parameters of batifiban and batifiban coadministered with antithrombin agents showed no significant differences. The mean inhibition rate of platelet aggregation (%) suggested that neither batifiban alone nor antithrombin agents alone could provide such potent inhibition rate (>80%) to obtain the best clinical efficacy, but they had a synergistic effect on platelet inhibition. No serious adverse effects were observed. The results in these healthy subjects suggest that batifiban coadministrated with antithrombin agents could achieve optimum clinical treatment effect for patients with NSTE ACS, and also those scheduled for percutaneous coronary intervention.

Wireless communication and multimedia applications feature a large amount of matrix operations with different matrix size. These operations require accessing matrix in column order. This paper implements a Multi-Grained Matrix Register File (MMRF) that supports multi-grained parallel row-wise and column-wise access. We implement a 4*4 MIMO decoding with the help of MMRF to illustrate the efficient matrix operations on SIMD processors. Experimental results show that, compared with TMS320C64x+, our SIMD processor can achieve about 5.65x to 7.71x performance improvement by employing the MMRF. By customized design technology, we reduce the area and critical-path delay of MMRF by 17.9% and 39.1% respectively.

This paper introduces a new concept about the mechanism of wear resistance to abrasives contained mainly in soil. This mechanism, which is called the theory of spontaneous protective layer in this paper, is dealt with. Some practical examples using this mechanism to increase the life of test samples and soil-cutting elements are also presented.

Due to the vast volume of publications in nowadays research environment, methods for analyzing, organizing, and accessing information from large databases are in great need. Through appropriate analytic tools, competitive intelligence can be revealed to enhance the organization or individual performance. This article will show how a free software package called CATAR carry on the analysis about the literature of the Adult Education science. Adult Education Quarterly (AEQ) is a scholarly forum of research and theory in adult education. The field of adult education is broad-based and inter disciplinary, during 1990 to 2010 having 672 papers from the ISI Web of Knowledge database was collected. The data analyzed include the distribution of authors' countries, topical clusters, the most cited references, the productivity rankings, and others to provide information for further study. Our analysis scenario also suggests a feasible way of analyzing other similar data for readers interesting in literature mining applications.

Technical education mainly focuses on the development of students’ motor skills. At vocational educational schools in Taiwan, technical teachers usually teach skills in a big class. Therefore, those teachers always face the problems of not realizing students’ learning process and difficulties; the evaluation is also deficient in credibility and validity.

A new single-mode 1/spl times/3 equal-power divider using a substrate microprism and two waveguide expanders has been proposed and analyzed. Simulation results show that with appropriate phase-front tilt and field modification, equal power division and low insertion loss can be attained for a large branching angle. The effects of device parameters are also discussed to facilitate the design of the proposed equal-power divider. Because of not requiring extra regions of indices different from those of the waveguide and substrate, the proposed equal-power divider can be easily fabricated.