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The real-time tracking of human targets by mobile robot was prone to problems such as scale variations, occlusion and deformation of targets. Aiming at above problems, an improved kernel correlation filtering algorithm (OURS algorithm) based on high-confidence update strategy of model and scale was proposed. The method of one-dimensional fast discriminative scale space was used to solve the problem that the kernel correlation filtering algorithm can't deal with the scale variation. A new confidence measurement method was proposed to judge the detection results of OURS algorithm model. When the target was completely occluded, it switched to Kalman filter algorithm to predict the position of the target. The confidence degree of the scale detection was judged to avoid the wrong scale update of tracking box. Through the video sequence simulation experiment and real environment test, the target tracking effect of the OURS algorithm was verified and compared with that of kernel correlation filter(KCF) algorithm and fast discriminative scale space tracking (fDSST) algorithm. The results show that the proposed OURS algorithm has the precision of 0.758, and the success rate of 0.711, and the target tracking effect of OURS algorithm was obviously improved compared with KCF, fDSST algorithms. The tracking box can still accurately frame the target after the scale variation, occlusion, deformation of pedestrian target, and other factors. The pedestrian tracking system of mobile robot based on image servo control strategy can adjust the linear velocity and angular velocity to maintain a stable following according to the position of the pedestrian. [ABSTRACT FROM AUTHOR]

To construct a recombinant replication-defective human adenovirus type 5 expressing Cap protein of PCV2 and test the immunological efficacy in mice. In this study, the recombinant replication-defective human adenovirus type 5, named as rAd5-Cap (wt-rAd5), was constructed through homologous recombination internally in the HEK293AD cells after co-transfection of the Pac I-linearized backbone plasmid and the shuttle plasmid pacAd5CMV-Cap containing the open reading frame (ORF2) of the porcine circovirus type 2 (PCV2) cap protein or pacAd5CMV without inserted fragment. Furthermore, the rAd5-Cap could induce the expression of PCV2 cap protein in the HEK293AD cells with high efficacy evaluated by the RT-PCR and indirect immunofluorescence assay (IFA). The virus titer of rAd5-Cap could reach up to 10(8.5) TCID50/mL similarly to that of wt-rAd5, indicating that there was little affect on the virus proliferation after the insertion of PCV2 cap protein gene. The humeral immune responses could be activated and detected 14 days after the inoculation of the mice with 10(7) TCID50 rAd5-Cap intramuscularly, and constantly in crease in another 14 days. These molecular biological and animal experiments results demonstrated that the PCV2 cap protein could be efficiently expressed by the recombinant adenovirus rAd5-Cap in eukaryotic cells and induce robust immune responses in mice, which laid a good foundation for the development of new type vaccine against porcine circovirus.