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Background:: Owing to the ability of a deep learning algorithm to identify objects and the related detection technology of security inspection equipment, in this paper, we propose a progressive object recognition method that considers local information of objects. Methods:: First, we construct an X-Base model by cascading multiple convolutions and pooling layers to obtain the feature mapping image. Moreover, we provide a “segmented convolution, unified recognition” strategy to detect the size of the objects. Results:: Experimental results show that this method can effectively identify the specifications of bags passing through the security inspection equipment. Compared with the traditional VGG and progressive VGG recognition methods, the proposed method achieves advantages in terms of efficiency and concurrency. Conclusion:: This study provides a method to gradually recognize objects and can potentially assist the operators in identifying prohibited objects.

Novel 600V integrable dual-trench (split-gate-trench and oxide-trench) power LDMOS (DT-MOS) with a reduced specific on-resistance and enhanced switching performance is proposed. The dual-trench structure reshapes the electric field by wrapped drift-region togerther with lateral depletion effect of the MIS structure, enabling voltage support capability with reduced specific on-resistance (Ron,sp). Breakdown voltage (BV) of 630V and Ron,sp of 4.0ohm• mm2 are obtained by simulation, and the proposed DT-MOS exhibits almost the highest power figure of merit (FOM, defined as BV2/Ron,sp) and better switching performance compared with the published structures. A low-cost (less mask-layers needed and no epitaxy process) and high reliability (relatively improved process tolerance) technology is exhibited, in which dual-trench is achieved using 14.0μm trench-etch process and inter-diffused process after ion-implantation.

An optocouplerless two-stage high power factor LED driver is proposed in this paper. The first stage is an optocouplerless isolated PFC converter and the second stage is a constant-current controlled non-isolated DC/DC LED driver. Optocoupler and secondary amplifier circuit of the first PFC stage can be removed. Besides, the output capacitor s of the PFC stage can be reduced due to low output ripple voltage requirement and acceptable wide input voltage range of the secondary stage in the two-stage LED driver. Hence the circuit structure of the proposed optocouplerless two-stage high power factor LED Driver is much simplified. A prototype LED driver for 12W LED fluorescent tube is built up to verify theoretical analysis and experiment results are presented.