Browsing by Subject "Operating characteristics"

Now showing 1 - 2 of 2

Open Access
Designing circular CMUT cells using CMUT biasing chart
(IEEE, 2012-10) Köymen, Hayrettin; Atalar, Abdullah; Oğuz, H. Kağan
A very accurate equivalent circuit model for circular CMUT cell is recently proposed. As a consequence of this model, the operating characteristics of the cell is derived and presented as a biasing chart for CMUTs. We discuss these operating characteristics and show how the coupling coefficient can be derived from the model. We present an analysis of receiver performance of a CMUT cell. We also demonstrate how to design cells for fixed bias voltage but for different static depression. © 2012 IEEE.
Open Access
Quality control chart design under jidoka
(John Wiley & Sons, Inc., 2009) Berk, E.; Toy, A. Ö.
We consider design of control charts in the presence of machine stoppages that are exogenously imposed (as under jidoka practices). Each stoppage creates an opportunity for inspection/repair at reduced cost. We first model a single machine facing opportunities arriving according to a Poisson process, develop the expressions for its operating characteristics and construct the optimization problem for economic design of a control chart. We, then, consider the multiple machine setting where individual machine stoppages may create inspection/repair opportunities for other machines. We develop exact expressions for the cases when all machines are either opportunity-takers or not. On the basis of an approximation for the all-taker case, we then propose an approximate model for the mixed case. In a numerical study, we examine the opportunity taking behavior of machines in both single and multiple machine settings and the impact of such practices on the design of an X̄ - Q C chart. Our findings indicate that incorporating inspection/repair opportunities into QC chart design may provide considerable cost savings.