Effect of Nozzle Internal Contour on Jet Aeroacoustics

2004 ◽  
Author(s):  
Krishna Viswanathan ◽  
L. Clark
Keyword(s):  
Internal Contour

scholarly journals Nests of Eufriesea aff. auriceps (Hymenoptera, Apidae, Euglossini) in remnants of Atlantic Forest and reforested areas

Sociobiology ◽  
2021 ◽  
Vol 68 (3) ◽  
Author(s):  
André Luis Gobatto ◽  
Amanda Guimarães Franciscon ◽  
Natalia Uemura ◽  
Susanna Mendes Miranda ◽  
Giovanna Gabriely Cesar ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Internal Diameter ◽  
Nest Architecture ◽  
Southern Brazil ◽  
Total Size ◽  
Internal Contour ◽  
Orchid Bee ◽  
Trap Nests ◽  
Forest Remnants ◽  
Trap Nest

In recent decades, the use of the trap-nest technique has helped to increase knowledge on the nest architecture of many orchid bee species. This study describes the nest architecture of Eufriesea aff. auriceps constructed in trap-nests made of dried bamboo internodes (canes). The nests were placed in remnants of Atlantic forest and in reforested areas next to forest remnants and monitored monthly from August 2015 to August 2016 and from August 2018 to August 2019 in southern Brazil. The bamboo internodes occupied by bees varied in internal diameter from 1.0cm to 2.0 cm (`X = 1.7; SD = 0.3; N = 12) and in length from 11.0 cm to 28.0 cm (`X = 19.5; SD = 4.8; N = 12). The total size of the nests inside the bamboo internodes ranged from 9.0 cm to 19.9 cm (`X = 14.3; SD= 3.9; N = 12). The number of brood cells constructed per nest varied from 1 to 10 (`X = 4.0; SD = 2.3; N = 15). The cells were built with small pieces of bark cemented with resin, linearly arranged along the bamboo tube. Internally, the cell wall was lined with resin. The cells measured 1.5-3.0 cm (`X = 2.3 ± 0.5; N = 48) in length and 1.4-1.7 (`X = 1.5 ± 0.1; N = 17) cm in width. The internal contour of the cells was elliptical. Females of Eufriesea aff. auriceps occupied trap-nests in both the forest remnants and in areas undergoing restoration.

Effect of Nozzle Internal Contour on Jet Aeroacoustics

2004 ◽  
Vol 3 (2) ◽  
pp. 103-135 ◽  
Author(s):  
K. Viswanathan ◽  
L. T. Clark
Keyword(s):  
Internal Contour

Determination of Stressed-Deformed State of Fine Disc Tools with Inner Cutting Section under Conditions of their Pre-Stressing

2014 ◽  
Vol 657 ◽  
pp. 73-77
Author(s):  
Aleksandr Mikhaylov ◽  
Hanna Dolhykh ◽  
Maxim Casian
Keyword(s):  
High Speed ◽  
Cutting Tools ◽  
Dynamic Component ◽  
Internal Contour ◽  
Tangential Stresses ◽  
Disc Cutting ◽  
Controlling Elements ◽  
Deformed State ◽  
Resonance Oscillations

The work is dedicated to investigation of the particulars of stressed-deformed state of fine disc tool with internal cutting section under conditions of its pre-stressing. It was suggested for reduction of tools oscillations at cutting to apply pre-stressing of the tools disc by means of controlling elements. The elements, which control the elements stress allowed to eliminate self-oscillations and resonance oscillations of the tool at high-speed materials cutting. In the paper the problem of evaluation of stress and deformed state of fine disc cutting tools with application of the method of finite elements (FEM) was solved. The article also contains epures of tangential stresses inside the internal contour of disc tools. On the basis of the investigations performed the synthesis for design of the main elements of fine disc tools with inner cutting section was carried out. The performed investigation was aimed at improving of the quality and stability of cutting with fine disc tools under conditions of high-velocity cutting and in presence of a dynamic component of the cutting process, ensuring improvement in durability and productivity of the tool.

ANALYTICAL AND NUMERICAL COMPARATIVE STUDY OF PROBLEM IN 2D ELASTICITY OF A HOLLOW TUBE SUBJECT TO NORMAL AND SHEAR STRESSES IN THE INTERNAL CONTOUR

2017 ◽  
Author(s):  
Thiago Arnaud Abreu de Oliveira ◽  
Rodolfo de Azevedo Palhares ◽  
Danilo Carvalho de Moura ◽  
Luís Vinícius Pereira Silva ◽  
Luciano Lins Vieira ◽  
...  
Keyword(s):  
Comparative Study ◽  
Shear Stresses ◽  
Internal Contour ◽  
2D Elasticity ◽  
Normal And Shear Stresses

Internal Contour Extraction Algorithm Based on Quadratic B-spline for Images of Hot Long Shaft Forgings

2012 ◽  
Vol 472-475 ◽  
pp. 2274-2278
Author(s):  
Zhe Lin Li ◽  
Qin Xiang Xia ◽  
Yong Pan ◽  
Zhi Wu
Keyword(s):  
3D Reconstruction ◽  
Measurement Method ◽  
Hot Forging ◽  
Feature Points ◽  
Contour Extraction ◽  
Maximum Correlation ◽  
Internal Contour ◽  
B Spline ◽  
Spline Curve ◽  
Extraction Algorithm

It is necessary that the internal and external contours are extracted from the image of hot long shaft forgings, while the forgings are measured by CCD measurement method. In the light of the blurry internal edges in the image of the hot forging, a method based on quadratic B-spline curve is employed to extract feature points. In order to remove the pseudo features, a method based on maximum correlation is presented. In accordance with continuity of the internal contours, quadratic B-spline curve is used to fit the internal contours. Experiments show that this algorithm can effectively extract accurate internal contours for images of hot squaring and chamfering forgings. The extracted contours could provide basic data for subsequent 3D reconstruction and geometric measurements.

Visual Attention in Infants: A Study of Stimulus Complexity, Habituation, and Sex Differences

1982 ◽  
Vol 54 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Margery Mitchell ◽  
A. Ivinskis ◽  
D. C. Finlay
Keyword(s):  
Sex Differences ◽  
Visual Attention ◽  
Stimulus Pattern ◽  
Stimulus Complexity ◽  
Response Decrement ◽  
Head Turning ◽  
Internal Contour ◽  
Complex Patterns

A modification of Cohen's (1973) method was used to study responses to patterns of varying complexity in 4-mo.-old infants. Complexity in this context was defined in terms of the number of elements and the degree of internal contour contained in a given pattern. The infants were first presented with small red circles on two trials. This was followed by 16 trials of exposure to either 2 × 2 or 8 × 8 or 24 × 24 small red-circle matrix patterns which again were followed by two further exposures (trials) to the small red circle. Response decrement across trials was measured as a function of fixation, i.e., the duration of time the infant was judged to be looking at the stimulus, and latency, i.e., the time it took the infant to orient toward the stimulus pattern. Infants preferred the more complex patterns. All infants showed decrement in duration of fixation across trials for all three types of pattern. Latency of head turning did not change across trials but differed between pattern types. There were no significant sex differences in habituation rates as measured by duration of fixation and latency.

scholarly journals Variation of the Gas Formation Regions within a Cigarette Combustion Coal during the Smoking Cycle

1981 ◽  
Vol 11 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Richard R Baker
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Diffusion Processes ◽  
Product Formation ◽  
Quadrupole Mass ◽  
Internal Contour ◽  
Formation Region ◽  
Gas Formation ◽  
Combustion Region ◽  
Filtration Unit

AbstractInternal contour distributions for gas temperatures and for the concentrations of carbon monoxide, carbon dioxide, hydrogen, propane and oxygen have been determined at successive times before, during and after a puff of a burning cigarette. The cigarette was smoked in an atmosphere of 21 % (v/v) oxygen in argon. The gases were withdrawn from the cigarette through a small sampling probe and filtration unit, and analysed using a quadrupole mass spectrometer. The contour distributions show that the gas formation and transmission processes occurring in the coal, and their variation during the smoking regime, are complex. The interior of the coal is almost entirely devoid of oxygen. The consumption of oxygen is so rapid that the position of its major influx into the coal, near the paper burn line, cannot be seen on the contour diagrams during a puff. However, the oxygen influx during the puff leaves burnt-out channels in the coal which become evident at later stages in the smoking cycle. When the puff ends, the product formation/transfer balance is interrupted, resulting in a local build-up of the product in its formation region. This local build-up reaches a maximum at 0.5-1.0 seconds after the end of the puff, after which time diffusion processes deplete the level. During the static smoulder period, distinct high and low temperature regions for the formation of carbon monoxide and dioxide are not evident inside the coal. However, towards the latter half of the puff, a distinct carbon dioxide formation region starts to appear behind the completely oxygen-deficient region. Application of the pyrolysis computer model, developed previously, confirms that this second region is a thermal decomposition region, and shows that such a region for carbon monoxide is not resolved from the combustion region.

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