We derive cooling rate and coefficient of performance as well their variances for a quantum Otto engine proceeding in finite-time cycle period. This machine consists two driven strokes, where the system isolated from heat reservoir undergoes unitary transformation, isochoric steps, system-bath interaction durations take away equilibrium even at respective ends stages. explicitly calculate stati...

We find evidence of a period doubling bifurcation and transition from pseudo-periodic chaos to a stable limit cycle during onset of ventricular fibrillation (VF) in humans. Novel radial basis modeling techniques are applied to time series of spontaneous VF to estimate time dependent changes in the dynamics. Furthermore, we show that the spectral power content may be used as a surrogate for the ...

We develop an inventory model to determine optimal ordering policy under permissible delay in payment by considering demand rate to be stock dependent. Mathematical models are derived under two different cases: credit period being greater than or equal to cycle time for settling the account, and credit period being less than or equal to cycle time for settling the account. The results are illus...

Inventory models in which the demand rate dependents on the stock- dependent are based on the common real- life observation that greater product availability tends to stimulate more sales. In this study we develop an inventory model to determine an optimal ordering policy for quantity dependent demand rate and time dependent holding cost items with delay in payments permitted by the supplier un...

In this paper we consider a single machine system that produces items part of which are defective. The defective items produced in a time period, consisting of several equal cycles, are accumulated and are all reworked in the last cycle of this period called the rework cycle. At the end of the rework cycle the whole process will start all over again. The first significant objective of this stud...

In this paper we consider an imperfect production system which produces good and defective items and assume that defective items can be reworked. Due to the nature of rework process we do not restrict the rework rate to be equal to normal production rate or constant and assume that it is a random variable with an arbitrary distribution function. We also assume as it is true in most real world s...