The acoustic radiation force on a solid sphere suspended freely in a plane progressive sound field is calculated taking into account the elasticity of the sphere. The radiation force versus ka curve, ka being the radius times the wavenumber in the surrounding medium, shows sharp maximums or minimums corresponding to resonance in every normal mode of free vibration of the sphere. The measurements made in our laboratory are in good agreement with the theory. The accuracy of absolute acoustic-intensity determination by the radiation-force method will be improved by the use of the present theory instead of King's.
The acoustic radiation pressure resulting from a plane wave incident on spherical shells and cylindrical shells immersed in a fluid is investigated theoretically in relation to the thickness of the shell and the contents of the hollow region. The results for the frequency dependence of acoustic radiation pressure computed on the basis of the theory are demonstrated for stainless shells with the hollow region filled water or air. Significant differences in acoustic radiation pressure occur when the interior region is changed from water to air.
This paper presents an approximation method for analyzing open restricted queueing networks with exponential service time and Poisson arrivals. Analysis is made by node-by-node decomposition through the introduction of a pseudo-arrival rate and an effective service rate. The method is applied to example networks and evaluated by comparing the results obtained thereby with those by simulations or exact calculations. We find that this method provides a fairly good approximation procedure for obtaining system performance measures such as blocking probabilities, output rates, etc., in open restricted queueing networks.
The acoustic radiation force experienced by a solid cylinder suspended freely in a plane progressive sound field is calculated, taking into account the elasticity of the cylinder. The results of numerical calculations are presented, indicating the ways in which the form of the frequency dependence of the radiation force function YP for cylindrical targets is affected by variations in the material parameters of the cylinder. The results are compared with those for solid spherical targets.
InBroadband ISDN, different classes of traffic expect to receive different quality of service. One way of providing service is to implement a priority structure among traffic classes. We analyze a single server queue in which video and voice traffic receive priority over data traffic. Corresponding t o the fixed cell size of ATM, we assume that service times are deterministic. We further assume that the high priority traffic is correlated and the arrivals are governed by a Markov chain. With these assumptions, we characterize the queue length distributions and the waiting time distributions for this problem. We show by numerical examples that the delay distribution depends highly on the correlations and that a priority service discipline is capable of providing very good service for real time traffic.Iieywords-B-ISDN, multiple traffic classes, priorities, discrete-time queues.
The acoustic radiation force on a solid sphere in a wave field in an inviscid fluid has been investigated theoretically and numerically taking into account the effects of elasticity of the sphere material for the following three cases: (I) the wave field is stationary, (II) the wave field is quasistationary, (III) the sound absorption in the sphere material is taken into account in each case above. The results show several features quite different from the rigid sphere solution.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.