List of Articles Cost optimization Open Access Article Abstract Page Full-Text 1 - Vacation model for Markov machine repair problem with two heterogeneous unreliable servers and threshold recovery Madhu Jain Rakesh Kumar Meena Open Access Article Abstract Page Full-Text 2 - A new approach for constraining failure probability of a critical deteriorating system Yard crane scheduling in port container terminals using genetic algorithm H Babaei K Shahanaghi A Bakhsha