Test conditions for vertical surface type broaching machines � Testing of accuracy

2019 ◽  
Author(s):  
Douglas A. Potts ◽  
Jonathan R. Binns ◽  
Hayden Marcollo ◽  
Andrew E. Potts

Abstract This project investigates a cantilevered cylinder projecting down into the water column moving at high velocity through still water, as is applicable to submarine masts. Surface-piercing cylinders differ from fully submerged cylinders due to the generation of surface wakes and under increasing flow speeds the formation of a ventilated pocket in the lee of the cylinder, both of which grow with increasing velocity, with concomitant effects on the hydrodynamic loading. The relative length of submergence, or immersed aspect ratio (L/D) and end conditions of the cylinder with respect to tip vortex drag effects may also impact the hydrodynamic loads and wake formation. Laboratory testing of surface-piercing cylinders to date has predominantly been confined to characterising the wakes shed from a rigid cylinder cantilevered down into the water from a towing tank carriage, which under certain test conditions will also exhibit significant Vortex-Induced-Vibration (VIV), though not adequately identified and accounted for in its magnification of drag and wake.


Author(s):  
George C. Ruben

Single molecule resolution in electron beam sensitive, uncoated, noncrystalline materials has been impossible except in thin Pt-C replicas ≤ 150Å) which are resistant to the electron beam destruction. Previously the granularity of metal film replicas limited their resolution to ≥ 20Å. This paper demonstrates that Pt-C film granularity and resolution are a function of the method of replication and other controllable factors. Low angle 20° rotary , 45° unidirectional and vertical 9.7±1 Å Pt-C films deposited on mica under the same conditions were compared in Fig. 1. Vertical replication had a 5A granularity (Fig. 1c), the highest resolution (table), and coated the whole surface. 45° replication had a 9Å granulartiy (Fig. 1b), a slightly poorer resolution (table) and did not coat the whole surface. 20° rotary replication was unsuitable for high resolution imaging with 20-25Å granularity (Fig. 1a) and resolution 2-3 times poorer (table). Resolution is defined here as the greatest distance for which the metal coat on two opposing faces just grow together, that is, two times the apparent film thickness on a single vertical surface.


2020 ◽  
Vol 63 (11) ◽  
pp. 3855-3864
Author(s):  
Wanting Huang ◽  
Lena L. N. Wong ◽  
Fei Chen ◽  
Haihong Liu ◽  
Wei Liang

Purpose Fundamental frequency (F0) is the primary acoustic cue for lexical tone perception in tonal languages but is processed in a limited way in cochlear implant (CI) systems. The aim of this study was to evaluate the importance of F0 contours in sentence recognition in Mandarin-speaking children with CIs and find out whether it is similar to/different from that in age-matched normal-hearing (NH) peers. Method Age-appropriate sentences, with F0 contours manipulated to be either natural or flattened, were randomly presented to preschool children with CIs and their age-matched peers with NH under three test conditions: in quiet, in white noise, and with competing sentences at 0 dB signal-to-noise ratio. Results The neutralization of F0 contours resulted in a significant reduction in sentence recognition. While this was seen only in noise conditions among NH children, it was observed throughout all test conditions among children with CIs. Moreover, the F0 contour-induced accuracy reduction ratios (i.e., the reduction in sentence recognition resulting from the neutralization of F0 contours compared to the normal F0 condition) were significantly greater in children with CIs than in NH children in all test conditions. Conclusions F0 contours play a major role in sentence recognition in both quiet and noise among pediatric implantees, and the contribution of the F0 contour is even more salient than that in age-matched NH children. These results also suggest that there may be differences between children with CIs and NH children in how F0 contours are processed.


2004 ◽  
Vol 63 (3) ◽  
pp. 143-149 ◽  
Author(s):  
Fred W. Mast ◽  
Charles M. Oman

The role of top-down processing on the horizontal-vertical line length illusion was examined by means of an ambiguous room with dual visual verticals. In one of the test conditions, the subjects were cued to one of the two verticals and were instructed to cognitively reassign the apparent vertical to the cued orientation. When they have mentally adjusted their perception, two lines in a plus sign configuration appeared and the subjects had to evaluate which line was longer. The results showed that the line length appeared longer when it was aligned with the direction of the vertical currently perceived by the subject. This study provides a demonstration that top-down processing influences lower level visual processing mechanisms. In another test condition, the subjects had all perceptual cues available and the influence was even stronger.


1973 ◽  
Vol 29 (01) ◽  
pp. 076-086 ◽  
Author(s):  
Uri Seligsohn ◽  
Samuel I. Rapaport ◽  
Ariella Zivelin

SummaryRabbits were injected with 75Se-Methionine (75SeM) 4-8 hr after being subjected to a variety of experimental conditions: injection of ACTH, growth hormone, glucagon, adrenalin, endotoxin, turpentine, hydrocortisone and laparotomy. All of these experimental conditions except injection of glucagon were associated with increased incorporation of 75SeM into fibrinogen. Three patterns of incorporation of 75SeM into plasma proteins were recognized: 1. the pituitary pattern, which was observed in animals injected with ACTH, growth hormone or endotoxin, and which was characterized by increased incorporation of 75SeM only into fibrinogen and by a delayed incorporation of 75SeM into α2 and β1 globulins; 2. the tissue injury pattern, which was characterized by a markedly increased incorporation of 75SeM into fibrinogen and no alteration in incorporation of 75SeM into α2 or β1 globulins; and 3. the pharmacologic corticosteroid pattern, which was characterized by a moderately increased incorporation of 75SeM into fibrinogen and a strikingly increased incorporation of 75SeM into α2 and β1 globulins.


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