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Because the integrated error measurement was not done in current micro-gear image measurement, the paper presents the virtual single-flank-meshing measuring methods of micro spur gear, and then introduces the principle, algorithm and digital simulation process of the virtual measurement. At first we constructed the standard involute spur gear, then the meshing process of the standard involute spur gear with the measured micro gear was simulated, in end the virtual measuring method of micro spur gear single flank meshing is studied, and its performance is verified, the method is feasible.

Selection of timetables for a transit system is a vital aspect of the schedule problem. An optimal model of timetables is presented for regional bus scheduling problem. Its objective is to optimize timetables in such a way that the transfer time of passengers at the transfer nodes is minimized while the operational constraints such as the traffic demand, departure time and maximum (minimum) headway are satisfied. This is a mixed integer nonlinear programming problem, which is difficult to solve using classical techniques. In this paper, modifications are made to Genetic Algorithm (GA) used to solve the problem. The Improved Genetic Algorithm (IGA) imports the simulated annealing algorithm to improve the premature and slow evolution speed phenomenon. In the last part, taking practical bus lines as an example, the reasonable of the model and the feasibility of the algorithm are tested.

Six chromone alkaloids were isolated from the root bark of SCHUMANNIOPHYTON MAGNIFICUM Harms. Three of these were identified as the known alkaloids schumanniophytine, schumannificine and N-methylschumannificine. The other three alkaloids are novel and were named isoschumanniophytine, anhydroschumannificine and N-methylanhydroschumannificine. In addition it was seen that the N-methylschumannificine isolated consisted of a mixture of two isomers and an alternative structure for schumanniophytine has been proposed.

Six further alkaloids have been isolated from the water-soluble fraction of the ethanolic extract of SCHUMANNIOPHYTON MAGNIFICUM Harms. Two of these are the known compounds trigonelline and rohitukine but the other four compounds are novel. Two of these, named schumagnine and N-methylschumagnine, consist of the chromone noreugenin linked to piperidine-related moieties whilst the other two are quaternary amines, the N-methyl analogues of schumanniophytine and isoschumanniophytine. The structures of these compounds have been deduced from their spectral characteristics and by chemical interconversions.