42 research outputs found
Experimental evaluation of confidence interval procedures in sequential steady-state simulation
Sequential analysis of simulation output is generally
accepted as the most efficient way for securing
representativeness of samples of collected observations.
In this scenario a simulation experiment is stopped when
the relative precision of estimates, defined as the relative
width of confidence intervals at an assumed confidence
level, reaches the required level. This paper deals with
the statistical correctness of the methods proposed for
estimating confidence intervals for mean values in
sequential steady-state stochastic simulation. We
formulate basic rules that should be followed in proper
experimental analysis of coverage of different steadystate
interval estimators. Our main argument is that such
analysis should be done sequentially. The numerical
results of our preliminary coverage analysis of the
method of Spectral Analysis (SA/HW) and Nonoverlapping
Batch Means are presented, and compared
with those obtained by traditional, non-sequential
approaches
Исследование влияния давления в реакторах на процесс каталитического риформинга бензинов
Freeman-Sheldon syndrome is defined as a combination of microstomia, deep set eyes, small palpebral fissures, arthrogryposis with ulnar deviation of the hand, talipes equinovarus and generalized muscular hypertension. Respiratory and swallowing problems are frequently encountered in these patients due to small orifices of mouth and nose. Obstruction of the upper airway tract resulting in tracheostomy has only been described twice. The described child manifested the typical dysmorphic features of Freeman-Sheldon syndrome and suffered from serious respiratory distress and swallowing difficulties from birth. The boy died at the age of 7 months after accidental decannulation of the tracheostoma during sleep. He did not show anatomical or histopathological abnormalities in the pharyngeal, laryngeal or tracheal regions. We assume that the only explanation of the repeated obstructive episodes is a functional muscular obstruction. Copyright © 2002 S. Karger AG, Basel