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A study is conducted to determine the effect of acoustic field on the thermal conductivity of composite propellants based on poly‐ butadiene and polyurethane binders. The thermal conductivity of the propellant is determined by a specially designed equipment. The thermal conductivity measurements are made in steady state conditions and in an acoustic field of constant amplitude at various frequencies ranging from 1 kHz to 6 kHz and at different temperatures ranging from 30°C to 50°C. The results indicate that the thermal conductivities of the composite propellants increase when they are subjected to an acoustic field. The data obtained are presented in the paper. Since the burning behaviour of solid propellants is influenced also by its thermal conductivity, the present work may be of direct relevance in improving upon some of the existing burning rate and combustion models.

.  Inventory models with integrated time-dependent demands for deteriorative items are considered in this study.  The demand models found in the literature include constant, linear, quadratic, exponential, price dependent, and stock dependent among others.  To wit, no study exists that uses integrated time-dependent demands.  Three models are developed:  The first model uses continuously compounded demands, the second model uses linear demands integrated with continuously compounded demands, and the third model uses quadratic demands integrated with continuously compounded demands.  Mathematical models are delineated for each model and relevant examples are provided to elucidate the proposed procedure.  The objective herein is to obtain optimum order quantities and order intervals concerning the overall cost.  Sensitivity analysis is provided for each of the three models.  The necessary data was generated using Visual Basic 6.0..  Inventory models with integrated time-dependent demands for deteriorative items are considered in this study.  The demand models found in the literature include constant, linear, quadratic, exponential, price dependent, and stock dependent among others.  To wit, no study exists that uses integrated time-dependent demands.  Three models are developed:  The first model uses continuously compounded demands, the second model uses linear demands integrated with continuously compounded demands, and the third model uses quadratic demands integrated with continuously compounded demands.  Mathematical models are delineated for each model and relevant examples are provided to elucidate the proposed procedure.  The objective herein is to obtain optimum order quantities and order intervals concerning the overall cost.  Sensitivity analysis is provided for each of the three models.  The necessary data was generated using Visual Basic 6.0.

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