In this paper, we consider two single server queueing systems to which customers of distinct priorities (P1 and P2) arrive according a Marked Markovian arrival process (MMAP). They are served phase type distributions. The probability P1 customer feedback is θ on completion his service. (P1) customers, as well P2 join the low priority queue. Low (P2) taken for service from head line whenever que...

As the largest coal exporting country in world, Indonesia needs efforts to prevent various negative things for mining activities maintain balance of surrounding nature. One many affected by is water. The wastewater quality must be checked regularly before it flows into water bodies. This research aims describe company's program created Safety Health & Environment (SHE) department and Center...