Bianchi-V string cosmological model and late time acceleration
  In the present work we have searched the existence of the late time acceleration of the universe with string fluid as source of matter in Bianchi V space-time. To get the deterministic solution, we choose the scale factor as increasing function of time that yields a time dependent deceleration parameter, representing a model which generates a transition of universe from early decelerating phase to recent accelerating phase. The study reveals that strings dominate the early universe and eventually disappear from the universe for sufficiently large times i. e. at present epoch. The same is observed by current astronomical observations. The physical behaviour of universe has been discussed in detail. 
Anil Kumar Yadav
physics.gen-ph