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Vehicle type recognition is a common question in modern intelligent transportation system. Although many methods have been proposed in literatures, how to recognize the vehicle type in the case of small samples is still troubling. To solve the problem mentioned above, this paper presents a method for vehicle type recognition based on a two-stage strategy that includes data preprocessing phrase and training phrase. The main purpose of the first stage is to remove the background of the vehicle image to reduce the interference of redundant information on subsequent stage. In second stage, a concept of multi-scale fusion feature which integrates handcrafted features with learning-based feature is to put forward to describe the characteristics of vehicles. The combined features are input to Support Vector Machine with Racial Basis Function (RBF-SVM) to train the recognition model. The proposed method is tested on MVVTR and the recognition accuracy is up to 90.96%, which is better than other methods. It is verified that strong generalization ability can be achieved in the case of small samples by using the two- stage strategy.

The AlGaN/InGaN/GaN high electron-mobility transistors (HEMTs) structure was grown by metal organic chemical vapor deposition (MOCVD) on (0001) sapphire substrates. The electron transport properties were investigated by variable temperature Hall effect measurements. The fabricated devices with gate length of 0.8mum and gate width of 120 mum show a transconductance of 136mS/mm and maximum drain current of 435mA/mm. The small signal properties were also achieved with the current gain cut-off frequency (fT) of 5.8GHz and the maximum frequency of oscillation (fMAX) of 17GHz

AlGaN/GaN HEMT gate leakage increasing induced by passivation was investigated by employing double gate surface leakage test structure, circle and rectangular Schottky contact structure and metal float gate structure. It was demonstrated that surface leakage is not a major contributor to increasing of gate leakage. Increase of gate leakage depends on augmenting of Schottky contact edge effect and inhibiting "visual gate" between gate and drain

This paper will discuss the process of T-shape gate that has been developed by direct-write electron beam lithography (EBL). The multilayer resist technique and different developing and lift-off are used to obtain a T-shape gate structure. The bottom of the "T" gate is about 100 nm. In order to realize the application of the T-shape gate in device, Heterojunction field effect transistors (HFET) have been fabricated using these T-gate structures. The extrapolated unity current gain frequency (f/sub t/) and transconductance (g/sub m/) of these transistors is 86.77 GHz and 450 ms/mm respectively.

A process for fabricating n-channel JFET/SOS (junction field-effect transistors on silicon-on-sapphire) has been researched. The gate p/sup +/-n junction was obtained by diffusion, and the conductive channel formed by a double ion implantation. Both enhancement and depletion mode transistors were fabricated in different processing conditions. From the results of the Co/sub 60/ /spl gamma/-ray irradiation experiments, we found that the devices had a good total dose radiation hardness. When the total dose was 5 Mrad(Si), their threshold voltages shift was less than 0.1 V. The variation of transconductance and the channel leakage current were also small.

CMOS/SOS devices have lower carrier mobility and higher channel leakage current than bulk silicon CMOS devices. These mainly result from the defects in the heteroepitaxial silicon film, especially from the defects near the Si-sapphire interface. This paper describes an experimental study of the improvement in CMOS/SOS devices characteristics resulting from improved epitaxial silicon quality which is obtained by modified solid phase epitaxy.