A novel coordinated power controller design framework is proposed to optimize the active power output of multiple generators in a distributed network. Each bus in the distributed generation systems includes two function modules: a distributed economic dispatch module and a cooperative control module. By virtue of the distributed consensus theory, a distributed economic dispatch algorithm is proposed and utilized to calculate the optimal active power generation references for each generator. The cooperative control module receives and tracks the active power generation references such that the generation-demand balance is guaranteed at minimum operating cost while satisfying all generation constraints. The distributed control and management strategies enhance the redundancy and the plug-and-play capability in microgrids. Optimal properties and convergence rates of the proposed distributed algorithms are strictly proved. Simulation studies further demonstrate the effectiveness of the proposed approach.

Unexpectedly strong geographic structures in many cosmopolitan species of marine holoplankton challenge the traditional view of their unrestrained dispersal and presumably high gene flow. We investigated cryptic lineage diversity and comparative phylogeography of a common estuarine copepod, Acartia tonsa, on the US Atlantic coast, using mitochondrial (mtCOI) and nuclear (nITS) gene markers. Three broadly sympatric lineages (F, S, X) were defined by genealogically concordant clades across both gene trees, strongly supporting recognition as reproductively isolated species. Limited dispersal seems to have had a major role in population differentiation of A. tonsa in general, with gene flow propensities rank ordered X > S > F. Geographic structure was found only at large scales (1000-2000 km) in X and S. Phylogeographic patterns in all three lineages were mostly concordant with previously recognized zoogeographic provinces but a large mid-Atlantic gap in the occurrence of lineage X, coupled with its presence in Europe, suggests possible nonindigenous origins. For lineage F, physiological adaptation to low-salinity environments is likely to have accentuated barriers to gene flow and allopatric differentiation at both regional and continental scales. Three allopatric F sublineages inferred a southern centre of origin and a stepwise northward diversification history at the continental scale. The most recently derived F sublineages, in the mid-Atlantic Bight, showed strong phylogeographic patterns at nITS albeit weaker at mtCOI. Applying a crustacean mtCOI molecular clock suggests that A. tonsa lineages diverged pre-Pleistocene but mid-Atlantic F lineage diversification may be post-Pleistocene.

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