In the first experimental study of memory for natural conversation, Keenan, MacWhinney, and Mayhew (1977) found that, even after 30 h, subjects had extremely good recognition memory for the exact wording of statements that contained information about a speaker's "intentions, beliefs, and his relations with the listener." Such sentences were said to be high in "interactional content." One possible interpretation of the results of Keenan et al. is that it is the immediate affective response to an utterance, rather than its interactional content, that increases its memorability. In the present study, the strong relationship between interactional content and memory found by Keenan et al. was replicated. Subjects showed excellent recognition memory for high interactional content statements from a conversation, even after a 72-h interval. However, there was very little relationship between arousal, as determined by subjects' electrodermal response (EDR), and subsequent memory. Moreover, involvement had its greatest effect not on memory, but on subjects' arousal as measured by EDR.308 Keenan, MacWhinney, and Mayhew (1977) conducted the first experimental study of memory for natural conversation. Their study was motivated by the observation that sentences spoken in natural conversation convey two fundamentally different types of information: propositional information and pragmatic information. Propositional information was characterized as information about the objects and events referred to by the sentence. Pragmatic information was defmed as information about the context of the sentence in the social interaction, including information about the speaker and "his intentions, beliefs, and his relations with the listener." Sentences that conveyed a great deal of pragmatic information referencing the speaker-listener interaction were said to be rich in "interactional content." Keenan et al. hypothesized that sentences with high interactional content would be highly memorable because "subsequent interactions with the speaker often depend upon the contents of earlier interactionally significant events" (p. 551). More important, they predicted that listeners would tend to remember the exact surface wording of This research was partially supported by National Institute of Education Grant NIE-G-78-0173 to J. Keenan. It is based in part on a master's thesis submitted by Peter Reinke to the Psychology Department of the University of Denver. Joseph Campos graciously made available to us the use of his laboratory, facilities, and equipment. He also provided us with valuable technical assistance and advice regarding the psychophysiological measurements. Without his help, the study could not have been conducted. We also wish to thank Suzanne Gendreau for testing the subjects in the control study and Polly Brown for conducting the statistical analyses of the data in the control study. Requests for reprints should be sent to Brian MacWhinney, Psychology Department, Carnegie-MellonUniversity, Pittsburgh, Pennsylvania 15213.Copyright 198...

The measurement of train resistance characteristics in railway tunnels can be a difficult and costly task. This is especially likely when the operator has to provide special trains and large numbers of staff. It would be a considerable advantage if the resistance characteristics could be measured during routine operation with scheduled trains. In May 1996, night-time tests were planned for aerodynamic measurements in the Grauholz Tunnel in Switzerland. They required the installation of pressure, velocity and temperature sensors in the tunnel. The opportunity was taken to record conditions during scheduled operation and this paper reports the use of the data to infer resistance coefficients of trains. It is shown that consistent interpretations are possible, but only when the gaps between successive trains are sufficiently large. Accurate measurements of air velocity are necessary to clarify conditions in the tunnel before train entry. The most important resistance parameter for a long train is its skin friction coefficient. It is found that this can be as low as 0.003 for a modern, streamlined passenger train, but as high as 0.010 for a non-uniform freight train.

This work presents an investigation of a new phenomenon of the Taylor-Couette flow: the onset of Taylor vortices in a cavitating fluid. This particular form of the Taylor-Couette flow develops if the shear flow between a rotating inner and a fixed outer cylinder approaches the critical Taylor number and the vapor pressure of the fluid simultaneously. This process is achieved by increasing the rotational speed of the inner cylinder, which causes an increase of the radial pressure gradient inside the laminar flow. The fully developed Taylor vortex flow is characterized by a pressure distribution in the azimuthal plane showing a local minimum adjacent to the wall of the inner cylinder between a pair of vortices that form a radial flow towards the outer cylinder. Thence, cavitation occurs simultaneously if the local pressure minimum drops below the vapor pressure of the fluid. This transition from a two-dimensional (Couette) into a three-dimensional (Taylor) flow triggered the idea to apply a newly developed unsteady 2-phase 3D-computational fluid dynamics code by computing the generation of vapor that is coinciding with the formation of Taylor vortices at the critical Taylor number. Whereas the results of a numerical simulation prove the existence of toroidal vapor caused by cavitation, the experimental validation demands additionally the development of a special fluid. Thus, the present work describes this specifically tailored fluid, which not only fulfills Taylor and pressure analogy but also features a favorable refractive index and a chemical suitability for the task.

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Abstract.Journal bearings are applied in internal combustion engines due to their favourable wearing quality and operating characteristics. Under certain operating conditions damage of the journal bearing can occur caused by cavitation. The cavitation reduces the load capacity and leads to material erosion. Experimental investigations of cavitating flows in dimension of real journal bearing are difficult to realize or almost impossible caused by the small gap and transient flow conditions. Therefore numerical simulation is a very helpful engineering tool to research the cavitation behaviour. The CFD-Code OpenFOAM is used to analyse the flow field inside the bearing. The numerical cavitation model based on a bubble dynamic approach and requires necessary initial parameter for the calculation, such as nuclei bubble diameter, the number of nuclei and two empirical constants. The first part of this paper shows the influence of these parameters on the solution. For the adjustment of the parameters an experiment of Jakobsson et.al.