Short cycle covers of cubic graphs and intersecting 5-circuits

A cycle cover of a graph is a collection of cycles such that each edge of the graph is contained in at least one of the cycles. The length of a cycle cover is the sum of all cycle lengths in the cover. We prove that every bridgeless cubic graph with $m$ edges has a cycle cover of length at most $212/135 \cdot m \ (\approx 1.570 m)$\mathrm{.}Moreover,ifthegraphiscyclically$4$-edge-connected we obtain a cover of length at most $47\mathrm{/}30\cdot m\approx 1.567m$.