In this report an analysis of data from a series of tests is presented on the stability of the toe structure of rubble mound breakwaters. The existing knowledge on toe stability and the influence of ...all governing parameters in the existing knowledge is reviewed.The tests which were performed for the present research are treated extensively. The main governing parameters, which determine toe stability in rubble mound breakwaters, are:Significant wave height: HsNominal stone diameter: Dn50Stone mass density: ρ sDepth above the toe: htDamage level: NodParameters investigated which appeared to have no significant influence are: the fictitious wave steepness sop and the width of the toe structure bt. The choice of the governing parameters, the definition of damage levels for the design of the toe structure and the way they are made dimensionless are motivated.The results from the present tests are compared with existing design formula.With the selected parameters two formulas have been derived from the available test data. One describes toe stability using the shallow water significant wave height Hs the other uses the shallow water 2% wave height H2%.The formulas are compared with existing test results and their range of application is given.
Working Hours of Junior Staff Dumoulin, J. G.; Grayson, M. J.; Hunt, A. C. ...
British Medical Journal,
06/1974, Letnik:
2, Številka:
5918
Journal Article
Ventilation In Operating Rooms [With Reply] Lidwell, O. M.; Lowbury, E. J. L.; Whyte, W. ...
British medical journal (Clinical research ed.),
04/1983, Letnik:
286, Številka:
6372
Journal Article
The study was carried out on 24 riding horses. In the first experience in 16 geldings, manual imitation of grooming in four left side body areas (mane, withers, lower shoulder and hips) was ...performed, while heart rate was telemetrically recorded. The procedure was carried out in a room normally used only for vaccinations and treatments. A Latin Square design with an extra period in four x four horses determined the sequences of the areas to be groomed. One minute of rest followed each three minutes of grooming. A three-minute control recording without grooming always preceded the Latin Square. Two-way ANOVA showed that grooming all four areas significantly decreased heart rate as compared with the control period (average: 15.6%), but that the effect was significantly stronger when the withers were groomed (22.1%). An effect of the sequence was also found, heart rate decreasing the more the procedure went on. The basal heart rate was rather high, probably because of several perturbing factors. In a second experience carried out in a different installation, other 8 horses were submitted to a similar treatment in their own box, in order to minimise any source of arousal and tension. The results suggest that grooming has less significant effect on heart rate when tension is minimal
Lo studio e' stato condotto su 24 cavalli da sella. Nella prima esperienza su 16 castroni, e' stata effettuata un'imitazione manuale del grooming in quattro aree del lato sinistro del corpo (collo, garrese, parte inferiore della spalla, fianco), mentre la frequenza cardiaca veniva registrata per via telemetrica. La procedura era eseguita in una stanza normalmente utilizzata solo per vaccinazioni e trattamenti. Uno schema a Quadrato Latino con extra periodo in 4 x 4 cavalli determinava le sequenze delle aree da sottoporre a grooming. Un periodo di controllo di tre minuti precedeva la procedura sperimentale. L'ANOVA a due vie evidenziava che il grooming di tutte quattro le aree determinava una diminuzione significativa della frequenza cardiaca rispetto al periodo di controllo (media: 15,6%), ma che l'effetto era significativamente piu' rilevante quando veniva trattato il garrese (22,1%). E' stato pure osservato un effetto della sequenza, dato che la frequenza cardiaca diminuiva man mano che si procedeva. La frequenza cardiaca di base risultava piuttosto elevata, probabilmente a causa di numerosi fattori di disturbo. In una seconda esperienza, condotta in un impianto diverso, sono strati sottoposti a un trattamento simile 8 cavalli nel loro box, allo scopo di rendere minima qualsiasi fonte di eccitazione e di disturbo. I risultati fanno ritenere che il grooming presenti un effetto sulla frequenza cardiaca meno significativo quando la tensione e' minima
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