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In this paper, we propose reliability adjustment weighted bit-flipping (RA-WBF) decoding algorithm for low density parity-check (LDPC) codes. By adjusting the reliability of received symbols during iterative decoding, the proposed algorithm can offer better tradeoff between performance, convergence speed and computational complexity. Furthermore, this improvement can easily be extended to other variations of weighted bit-flipping decoding algorithm and obtain noticeable improvement in error performance. Simulation results are shown to verify our conclusions.

Aiming at the optimization algorithm, weak filled function method is proposed and which with simple form is constructed. The restriction of this method is weaker than the known filled function method, thus it is easier to construct function and solve algorithm. The weak filled function method is feasible through the theoretical analysis, and the global minimum of simulation example can be obtained in its interval. The results indicate that weak filled function method is an effective method.

This paper provided a mathematic model for Three Gorges-Gezhou dam co-scheduling problems, based on full analysis of Three Gorges-Gezhou dampsilas actual needs, to maximize the total throughput of Three Gorges-Gezhou dam, to maximize the utilization ratio of shiplock area and minimize the total navigation shiplock waiting time under eight constraint conditions. Then a scheduling algorithm based on GA was pointed out. The Three Gorges south lock, Gezhou dam lock, the Three Gorges north lock were optimization searched separately in the GA algorithm. The scheduling results of the Three Gorges south lock were taken as the origin of the whole plan period, and also were taken as the basis of the Gezhou dam scheduling together with the ship applied information. The scheduling results of Gezhou dam were regarded as the basis of the Three Gorges north lock scheduling together with the ship applied information, so repeated, until the optimal scheduling results were given, or the most iterative step was reached. The applied result shows that making a period plan of two dam five lock only needs 2 minutes, and the plan is quite effective according to practical application.