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The linear consecutive-k-out-of-n: failure (good) (Lin/Con/k/n:F(G)) system consists of n interchangeable components that have different reliabilities. These components are arranged in a line path and different component assignments change the system reliability. The optimization of Lin/Con/k/n:F(G) system is to find an optimal component assignment to maximize the system reliability. As the number of components increases, the computation time for this problem increases considerably. In this paper, we propose a Birnbaum importance-based ant colony optimization (BIACO) algorithm to obtain quasi optimal assignments for such problems. We compare its performance using the Birnbaum importance based two-stage approach (BITA) and Birnbaum importance-based genetic local search (BIGLS) algorithm from previous researches. The experimental results show that the BIACO algorithm has a good performance in the optimization of Lin/Con/k/n:F(G) system.

We conducted four bird biodiversity surveys in the Putao area of northern Myanmar from 2015 to 2017. Combined with anecdotal information collected between 2012 and 2015, we recorded 319 bird species, including two species (Arborophila mandellii and Lanius sphenocercus) previously unrecorded in Myanmar. Bulbuls (Pycnonotidae), babblers (Timaliidae), pigeons and doves (Columbidae), and pheasants and partridges (Phasianidae) were the most abundant groups of birds recorded. Species richness below 1 500 m a. s. l. was higher than species richness at higher elevations. Our results suggest that the current protected areas in this region should be expanded to lower elevations to cover critical conservation gaps.