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681.
When repairable items sold under warranty fail, the rectification action taken by the manufacturer can be either a repair or a replacement. In this paper a new repair–replacement strategy is proposed for the manufacturer when the items are sold with a non-renewing free replacement warranty policy. The strategy involves splitting the warranty period into two intervals where only repairs are carried out, separated by a third interval with at most one replacement. 相似文献
682.
M. V. N. Murthy G. Ramachandran S. K. Singh 《Zeitschrift für Physik A Hadrons and Nuclei》1982,306(2):117-125
Pion photoproduction processes14Ngs(γ, π +)14C and14Ngs(γ, π ?)14O have been studied in the threshold region. These processes provide an excellent tool to study the corrections to soft pion theorems and Kroll-Ruderman limit as applied to nuclear processes. The agreement with the available experimental data for these processes is better with the empirical wave functions while the shell-model wave functions predict a much higher value. Detailed experimental studies of these reactions at threshold, it is shown, are expected to lead to a better understanding of the shell-model inputs and radial distributions in the 1p state. 相似文献
683.
We consider the problem where items are produced in lots and sold with warranty. Due to manufacturing variability, some items do not conform to the design specifications and their performance is inferior (for example, have higher failure rate). The warranty servicing cost for these is much higher than for those which conform. Two approaches have been advocated for reducing the warranty cost per item released and in both it is achieved at the expense of increased manufacturing cost. The first involves life testing to weed out nonconforming items and the second involves strategies to reduce nonconforming items being produced. In this paper, the authors develop a model which combines both approaches and quality control decisions are made optimally to minimize the total (manufacturing and warranty) cost. It extends the earlier models of the authors which deals with quality decisions based solely on either the first or the second approach. 相似文献
684.
For theB 2 Σ andX 2 Σ states of scandium monoxide, the potential energy curves are constructed by the Rydberg-Klein-Rees and the Morse methods. Morse model is shown to be adequate for the (B→X) band system of ScO. The re values are found to be 1.717 Å and 1.665 Å for theB andX states respectively. 相似文献
685.
CNDO/Force and compliance constant methods were applied to define general quadratic potential functions for F2CO and HCOF. A satisfactory set of compliants was obtained by suitably scaling down the stretching and stretch–stretch elements of the initial force constant matrix, evaluated by the CNDO/force approach, followed by fitting the compliants to available experimental data. 相似文献
686.
687.
R. Eggenhoffner C.S.N. Murthy F.G. Fumi 《Journal of Physics and Chemistry of Solids》1978,39(12):1295-1299
Some comments are presented on three phenomenological potentials for the alkali halide crystals proposed in recent years by Narayan and Ramaseshan, by Woodcock, and by Romano, Margheritis and Sinistri. In the context a brief comment is made on the van der Waals coefficients reported by Hajj. 相似文献
688.
In the analysis of clinical events associated with time, one often encounters dependent observations. The status of a patient at two different points of time during the course of treatment is one such example. In this paper, an appropriate model is assumed for the two random variables and a procedure is developed to answer the question: Do the two values, when compared, reflect a change in the patient? 相似文献
689.
690.
M. Ramakrishna Murthy B. Sanjeeva Rao 《Journal of Polymer Science.Polymer Physics》1990,28(2):133-138
Investigations on the effects of γ irradiation on poly(methylene oxide) (POM) and poly(ethylene oxide) (PEO) have been made employing electron spin resonance (ESR) spectroscopy. The ESR sextet and doublet spectra, recorded for POM and PEO, respectively, on irradition in air at room temperature are broadened as the temperature is lowered and show a reversible change in line shape with temperature. The spectra are analyzed by computer simulation, employing Lorentzian line-shape functions and the least-squares method of total curve fitting. The component spectra are evaluated and are assigned. Superposition of the component quartet, triplet, and doublet spectra, corresponding to the radicals ?H3, ?H2O , and O?HO , respectively, together with a singlet due to the radicals ?CH2 is considered to be the best fit to the observed spectrum for POM. The doublet spectrum recorded for PEO has been assigned to the radicals ?HO . The reversible broadening of the spectra has been associated with the mechanism of molecular motions around the glass transition temperatures of these polymers. 相似文献