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Flight path planning by artificial immune algorithm approach met the requirements of aircraft's flyability and operation is proposed for the problem of single and double TF/TA2 flight path planning. Punishment function (affinity function) with comprehensive 3D threat information is designed. A comprehensive threat model is formed including dynamic and static threats and no-fly-zone. Accordingly, single and dual flight paths are planned by AIA, which have been compared with the paths by GA. The results show that, GA's planned a quick and longer path compared under simple threat environment; in complex environments, GA has high failure rate (greater than 95%) for single aircraft, but it is failed for double aircrafts. For the single and double aircrafts, AIA can provides one optimal and more candidate optimal flight paths.

Computational efficiencies of traditional vector computing-based polygon clipping algorithms will decrease rapidly when handling polygons contain large amount of vertices. The computing flows of traditional polygon clipping algorithms are tightly coupled with special data structures, which difficult to be optimized in the underlying of them. Under the premise of meeting a certain degree of area errors, the polygon clipping problem can be solved by introducing the idea of rasterization processing. In this research, we proposed a new rasterization processing-based polygon clipping algorithm: the RaPC algorithm, on the basis of analyzing the characteristics of existing algorithms. The area errors of results of the new algorithm are also analyzed and discussed. Experimental results show that the efficiencies of the RaPC algorithm can be enhanced significantly when using large grid cells, and it shows a linear trend growth with the increase of amount of polygon vertices. Compared with the Vatti algorithm, the RaPC algorithm represents more efficiencies on dealing clipping issues between polygons with large amount of vertices, the former shows lower time costs when handling polygons with less vertices. The area error of computing results of the RaPC algorithm is closely related with the grid size, and errors can be reduced using smaller grid sizes. Therefore the RaPC algorithm showed higher efficiencies on processing polygons with large amount of vertices than the Vatti algorithm and presented practical values to some degree.

The cabbage armyworm, Mamestra brassicae, enters winter and aestival diapause in the pupal stage under 10L-14D and 16L-8D, respectively, at 23°C. It develops without pupal dormancy under 14L-10D at 23°C. In 6th-instar larvae, the hemolymph ecdysteroid titers as well as the activity and sensitivity of the prothoracic glands (PGs) were nearly the same in the diapause- and nondiapause-programmed larvae. In non-diapause pupae (ND-pupae), the ecdysteroid titer peaked in the first half of the pupal stage. By contrast, in winter and aestival diapause pupae (WD- and AD-pupae), the ecdysteroid titer remained low after pupation. The ecdysteroid titer in diapausing AD-pupae was 8- to 10-times higher than that in diapausing WD-pupae. PGs from 5th-instar and 6th-instar larvae, as well as those from pupae, secreted ecdysteroids and showed a far stronger response to big prothoracicotropic hormone (PTTH) than to small PTTH in vitro. PG activity and its sensitivity to big PTTH fluctuated in a stage-dependent mann...