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For high power and high voltage (HV) applications, low power subsystems must have an auxiliary power supply that can take wide-range high voltage input and can generate low DC voltage at the output. In order to improve the efficiency, silicon carbide (SiC) MOSFET with smaller on resistance are considered to replace silicon (Si) MOSFET, and the static and dynamic characteristics of two devices are compared and analyzed. Besides, the Quasi-Resonant (QR) topology is selected to reduce losses and Electromagnetic Interference (EMI) level. In this paper, a SiC-based QR flyback auxiliary power supply for high voltage applications is proposed, and the design scheme for auxiliary power supply is validated.

In adaptive optical (AO) systems, deformable mirrors are used to correct wavefront aberrations. In this study, we introduce various structural deformable mirrors used in low temperature environments: discrete actuators deformable mirror, bimorph deformable mirror, membrane deformable mirror and MEMS deformable mirror. And the basic working principle of these deformed mirrors is briefly described; the research results of low temperature deformable mirrors are presented in detail. According to formerly researches, we found out the two main factors influencing the performance of low temperature deformable mirrors. The advantages and disadvantages of various structural low temperature deformable mirrors are analyzed. Finally, the development trend of low temperature deformable mirrors is prospected.

In order to study the mechanism of the Vacuum Cavity explosion venting technology in the gas pipe, An L type simulation model referred to the experimental pipe is established in this paper, in which the Vacuum Cavity explosion venting is simulated by means of Fluent software. The change law of the pressure field, temperature field and velocity vector is obtained in the numerical simulation. After the data analysis, the conclusion is that, the propagation of the shock wave in the pipe accords with the fluid water-hammer phenomenon. The gas components which enter into the Cavity impact and neutralize each other before they vanish eventually and suspend the reaction chain of the combustion. The broken timing of weak panel of the cavity and the change of Cavity volume are the important factors that affect the Vacuum Cavity explosion venting.

High-brightness tapered laser diode at 850 nm was fabricated based on the AlGaInAs/A1GaAs chip with graded-index waveguide separate confinement hetero-structure.The tapered laser has better performance than the broad laser under the same condition.The lateral divergence angles of the tapered laser and the broad laser were 4° and 6° at the output power of 1 W,while the beam propagation factor M2 were 2.8 and 9.2,respectively.The slope efficiency of the tapered laser had a high value of 0.58 W/A and the conversion efficiency reached 30% in the output power 1.40 W under the injection current of 3 A.The facts indicated the tape-red laser would be an ideal choice for high brightness high power laser diodes.

Understanding the acid-tolerance ability of enteric human pathogens is critical in determining microbial food safety and the associated risk. We have discovered naturally occurring compounds in the spent growth media, which inhibit the acid-tolerance ability of several enteric human pathogens when challenged at pH 3.0 for 2 h at 37 degrees C. The compounds were detected in the spent growth media obtained from Escherichia coli O157:H7, Salmonella spp., and Vibrio cholera, but not from Shigella flexneri. The compounds were effective in reducing pathogen survival by 5-logs during acid-challenge assay. The low molecular weight (300 Da) and heat resistant nature (121 degrees C, 15 min, at 15 psi) of the compounds make them excellent candidates to explore their suitability as food additives that would increase microbial food safety.

In order to predict incremental spacing in press bend forming of Aluminum alloy integral panel,the typical integral panel test piece was taken as an example. By using numerical simulation method,this paper analyzed the effects of different incremental spacing on integral panel forming quality which included stress and strain distribution,curvature continuity,and surface profile. According to simulation results, experimental verification was implemented. The verification results show that the numerical simulation method to predict the incremental spacing is effective.

With the development of science technology, the computer networks systems has been widely used in all fields. However, threat to the security of computer networks systems has been a serious problem at present. So, this paper research and study on the computer networks systems from two main parts–main threat to the computer networks systems and computer networks systems security detecting technology.

This paper presented a pipelined 8B10B encoder for a high speed SerDes. To overcome the drawback of the speed limitation due to the conventional architecture, a pipelined encoding architecture is proposed. By splitting the longer path into two shorter paths with registers, the delay of the critical path is shortened greatly. Based on the pipelined architecture, a high-speed 8B10B encoder is implemented using 0.18 µm CMOS technology and standard cell library. Post-simulation results show that the encoder can work up to the rate of 7Gbps with a core are of 76.86 µm × 76.86 µm and the power consumption is 5.0317 mW under a 1.8V power supply voltage.