In some statistical process monitoring applications, quality of a process or product is described by more than one ordinal factors called ordinal multivariate process. To show the relationship between these factors, an ordinal contingency table is used and modeled with ordinal log-linear model. In this paper, a new control charts based on ordinal-normal statistic is developed to monitor the ord...

In statistical process control, the primary method used to monitor the number of nonconformities is the c-chart. The conventional c-chart is based on the assumption that the occurrence of nonconformities in samples is well modeled by a Poisson distribution. When the Poisson assumption is not met, the X-chart (individuals chart) is often used as an alternative charting scheme in practice. In thi...

This paper proposes three synthetic-type control charts to monitor the mean time-between-events of a homogenous Poisson process. The first proposed chart combines an Erlang (cumulative time between events, Tr ) chart and a conforming run length (CRL) chart, denoted as Synth-Tr chart. The second proposed chart combines an exponential (or T) chart and a group conforming run length (GCRL) chart, d...

background: iron-mediated cardiomyopathy is the main complication of thalassemia major (tm) patients. therefore, there is an important clinical need in the early diagnosis and risk stratification of patients. the aim of this study was to evaluate the efficacy of tissue doppler imaging (tdi) to study cardiac iron overload in patients with tm using t2* magnetic resonance (mr) as the gold-standard...

BACKGROUND Contrast sensitivity measurement in UK clinical practice is most commonly performed with the Pelli-Robson chart. AIMS To compare the repeatability of two new contrast sensitivity charts and to measure their agreement with the Pelli-Robson charts. METHOD Contrast sensitivity was measured monocularly using two versions of the Mars letter contrast sensitivity chart, two presentation...