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A synthetic control chart for detecting shifts in the process mean integrates the Shewhart [Formula: see text] chart and the conforming run length chart. It is known to outperform the Shewhart [Formula: see text] chart for all magnitudes of shifts and is also superior to the exponentially weighted moving average chart and the joint [Formula: see text]-exponentially weighted moving average charts for shifts of greater than 0.8σ in the mean. A synthetic chart for the mean assumes that the underlying process follows a normal distribution. In many real situations, the normality assumption may not hold. This paper proposes a synthetic control chart to monitor the process mean of skewed populations. The proposed synthetic chart uses a method based on a weighted variance approach of setting up the control limits of the [Formula: see text] sub-chart for skewed populations when process parameters are known and unknown. For symmetric populations, however, the limits of the new [Formula: see text] sub-chart are equivalent to that of the existing [Formula: see text] sub-chart which assumes a normal underlying distribution. The proposed synthetic chart based on the weighted variance method is compared by Monte Carlo simulation with many existing control charts for skewed populations when the underlying populations are Weibull, lognormal, gamma and normal and it is generally shown to give the most favourable results in terms of false alarm and mean shift detection rates.

Carbohydrates U 0500Microwave Irradiation for Accelerating the Synthesis of Thioglycosides. -A simple and efficient procedure for the synthesis of thioglycosides of type (III), (V),, (IX), and (XI) is described. The results, compared with those obtained for conducting the reactions without microwaves, show similar yields in shorter reaction times. -(EL ASHRY*, E. S. H.; AWAD, L. F.; ABDEL HAMID, H. M.; ATTA, A. I.; Synth.

The procedure of aspiration and tetracycline sclerotherapy was easy, safe and acceptable, with no recurrences. It appears to be a valid alternative to cyst aspiration in the management of simple ovarian cysts.

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This paper proposes a weighted variance method to compute the limits of the X and S charts for skewed distributions. The proposed charts extend the weighted variance X and R charts in [1] by enabling a process from a skewed distribution with moderate and large sample sizes to be monitored efficiently, hence producing more favourable Type-I and Type-II error rates than the charts in [1]. Note that the charts in [1] are only intended to be used for small sample sizes. The Type-I and Type-II error rates computed show that the proposed charts outperform the existing heuristic charts, as well as those in [1] for moderate and large sample sizes, involving cases with known and unknown parameters, when the distribution of a process is skewed.

The condensation of D-glucono- and D-galactono-1,5-lactone and thiocarbohydrazide to give 3-(D-alditol-1-yl)-4-amino-5-mercapto-1,2,4-triazoles 4 and 5 is accelerated by the use of microwave-assisted organic reaction (MAOS). The deamination and dethiolation of compound 4 to give 6 was also accelerated by the use of MAOS. Condensation of 4 and 5 with p-nitrobenzaldehyde afforded Schiff bases 8 and 9, respectively, within 4 min under microwave irradiation (MWI), whereas with ethyl chloroacetate the thioalkylated products 14 and 15 were obtained in 8 min. The structures of the synthesized compounds were confirmed by 1H NMR, 2D NMR, and mass spectra.