The nuclear (supernormal) cones were introduced by the regretted Professor George Isac (1981) and published in 1983. With his permission and for the first time we named them 'Isac's cones' in 2009. In memory of Professor Isac, we present some considerations of noticeable importance on this class...

Companies typically plan for warranty costs through creation of a reserve fund. Most researchers assume that the warranty reserve is set based on the expected total warranty costs. However, companies rarely keep reserves to cover their liabilities for the whole life of their products, since...

This paper presents a water supply problem arising from the regions where power supply is not regulated and the water supplier has to manage the demand with minimum possible cost. The consumption is constrained to organise rationing, and thus known day after day. Furthermore, the same...