scholarly journals Walruses produce intense impulse sounds by clap-induced cavitation during breeding displays

2021 ◽  
Vol 8 (6) ◽  
pp. 210197
Author(s):  
Ole Næsbye Larsen ◽  
Colleen Reichmuth
Keyword(s):  
Physical Fitness ◽  
High Speed ◽  
Sound Production ◽  
Effective Means ◽  
Sound Level ◽  
Mature Male ◽  
Human Care ◽  
Aquatic Mammals

Male walruses produce some of the longest continuous reproductive displays known among mammals to convey their physical fitness to potential rivals and possibly to potential mates. Here, we document the ability of a captive walrus to produce intense, rhythmic sounds through a non-vocal pathway involving deliberate, regular collision of the fore flippers. High-speed videography linked to an acoustic onset marker revealed sound production through cavitation, with the acoustic impulse generated by each forceful clap exceeding a peak-to-peak sound level of 200 dB re. 1 µPa. This clapping display is in some ways quite similar to the knocking display more commonly associated with walruses in rut but is produced through a very different mechanism and with much higher amplitudes. While this clapping behaviour has not yet been documented in wild individuals, it has been observed among other mature male walruses living in human care. Production of intense sounds through cavitation has previously been documented only in crustaceans but may also be an effective means of sound production for some aquatic mammals.

scholarly journals Features of Physical Preparation of Students for Passing the GTO Standards

2021 ◽  
Vol 4 (4) ◽  
pp. 22-26
Author(s):  
Oksana Anatolevna Sbitneva
Keyword(s):  
Physical Fitness ◽  
Physical Training ◽  
High Speed ◽  
Effective Means ◽  
Educational Process ◽  
Physical Culture ◽  
Successful Implementation ◽  
Positive Trend ◽  
Gradual Change ◽  
Educational Potential

The article deals with the problems of motor activity, the development of physical qualities and speed abilities of students. The importance of physical culture and physical fitness is revealed. The search for effective means and methods of physical culture in preparation for passing the GTO standards is analyzed. The features of physical training of high-speed orientation of students to pass the GTO standards for speed are considered. The effectiveness of the use of speed-oriented exercises, which are necessary for students to achieve the norms of the GTO complex for speed, within the framework of physical culture classes, is revealed. Research methods. In the course of the study, a comparative analysis of the results was carried out. The method of control tests was used. The overall assessment of the effectiveness of the above tools and methods is expressed in positive dynamics. The results of the study. According to the results of the study, there is a positive trend. The analysis of the results according to the table of GTO standards in the framework of physical culture classes allows us to note the growth of indicators for all established tests. Systematic classes using high-speed, high-speed and power-oriented exercises with a gradual change in the load, improving the technique of performing exercises, contribute to the development of the physical quality «speed». Conclusions. Regular physical education classes with the use of speed exercises contribute to the development and improvement of physical qualities, the achievement of growth rates of GTO standards. The level of readiness of students to fulfill the norms and requirements of the GTO complex at the average level. Affordable, effective means and methods of physical training make it possible to actively use the scientific and educational potential of the university. The purposeful organization of the educational process contributes to achieving the proper level of physical fitness necessary for the successful implementation of the regulatory requirements of the AR PCS Complex GTO.

scholarly journals Investigation of Flow Behavior around Corotating Blades in a Double-Spindle Lawn Mower Deck

2005 ◽  
Vol 2005 (1) ◽  
pp. 77-89 ◽  
Author(s):  
W. Chon ◽  
R. S. Amano
Keyword(s):  
Flow Pattern ◽  
High Speed ◽  
Flow Behavior ◽  
Flow Analysis ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Video Camera ◽  
Sound Level ◽  
Lawn Mower ◽  
Level Meter

When the airflow patterns inside a lawn mower deck are understood, the deck can be redesigned to be efficient and have an increased cutting ability. To learn more, a combination of computational and experimental studies was performed to investigate the effects of blade and housing designs on a flow pattern inside a1.1mwide corotating double-spindle lawn mower deck with side discharge. For the experimental portion of the study, air velocities inside the deck were measured using a laser Doppler velocimetry (LDV) system. A high-speed video camera was used to observe the flow pattern. Furthermore, noise levels were measured using a sound level meter. For the computational fluid dynamics (CFD) work, several arbitrary radial sections of a two-dimensional blade were selected to study flow computations. A three-dimensional, full deck model was also developed for realistic flow analysis. The computational results were then compared with the experimental results.

scholarly journals Songbirds use pulse tone register in two voices to generate low-frequency sound

2007 ◽  
Vol 274 (1626) ◽  
pp. 2703-2710 ◽  
Author(s):  
Kenneth K Jensen ◽  
Brenton G Cooper ◽  
Ole N Larsen ◽  
Franz Goller
Keyword(s):  
High Speed ◽  
Sound Production ◽  
Low Frequency ◽  
Pulse Generation ◽  
Sound Sources ◽  
Pulse Tone ◽  
Vocal Fold Dynamics ◽  
Vibration Pattern ◽  
Pulse Characteristics ◽  
Two Sides

The principal physical mechanism of sound generation is similar in songbirds and humans, despite large differences in their vocal organs. Whereas vocal fold dynamics in the human larynx are well characterized, the vibratory behaviour of the sound-generating labia in the songbird vocal organ, the syrinx, is unknown. We present the first high-speed video records of the intact syrinx during induced phonation. The syrinx of anaesthetized crows shows a vibration pattern of the labia similar to that of the human vocal fry register. Acoustic pulses result from short opening of the labia, and pulse generation alternates between the left and right sound sources. Spontaneously calling crows can also generate similar pulse characteristics with only one sound generator. Airflow recordings in zebra finches and starlings show that pulse tone sounds can be generated unilaterally, synchronously or by alternating between the two sides. Vocal fry-like dynamics therefore represent a common production mechanism for low-frequency sounds in songbirds. These results also illustrate that complex vibration patterns can emerge from the mechanical properties of the coupled sound generators in the syrinx. The use of vocal fry-like dynamics in the songbird syrinx extends the similarity to this unusual vocal register with mammalian sound production mechanisms.

Study on structure optimization of a bubble cap against erosion wear of an S Zorb desulfurization reactor distribution plate

2021 ◽  
pp. 095440892110424
Author(s):  
HZ Jin ◽  
SQ Gao ◽  
HL Zhao ◽  
C Wang ◽  
GF Ou
Keyword(s):  
High Speed ◽  
Effective Means ◽  
Structure Optimization ◽  
Erosion Wear ◽  
Particle Erosion ◽  
Two Phase ◽  
Wear Area ◽  
Inner Diameter ◽  
Distribution Plate ◽  
Semi Empirical

Bubble cap structures are researched for the particle erosion wear of the distribution plate (tray for short) in an S Zorb desulfurization reactor. The semi-empirical model of erosion wear prediction of gas–solid two-phase flow is revised by means of erosion wear experiments at high temperature and high speed. According to the revised erosion wear, the influence of the h0 (the distance from the bottom of the bubble cap to the tray), h1 (distance from the outlet of the lifting pipe to the top of the bubble cap interface), N (the number of cavities), d0 (the inner diameter of bubble cap) on erosion wear of trays are studied. The results show that a smaller h0 will make the erosion degree of the tray more serious; it is recommended to keep h0 = 17 mm. A larger h1 will alleviate the erosion wear degree of adsorbent particles on the tray, but considering the efficiency of the reaction, h1 = 36 mm is more appropriate. The increase of N reduces the erosion wear less but enhances the fluid disturbance and makes the erosion wear area unstable; so, N should be kept at 10. The increase of d0 reduces the velocity and density of fluid impacting the tray, thus reducing the erosion wear degree, which is an effective means.

Hygienic Effects of Trimming and Washing Operations in a Beef-Carcass-Dressing Process†

1996 ◽  
Vol 59 (6) ◽  
pp. 666-669 ◽  
Author(s):  
C. O. GILL ◽  
M. BADONI ◽  
T. JONES
Keyword(s):  
Escherichia Coli ◽  
Standard Deviation ◽  
High Speed ◽  
Effective Means ◽  
Arithmetic Mean ◽  
Single Sample ◽  
Aerobic Bacteria ◽  
E Coli ◽  
Beef Carcasses ◽  
The Mean

Swab samples were obtained from the surfaces of randomly selected beef carcasses passing through a high-speed dressing process. A single sample was obtained from a randomly selected site on the surface of each selected carcass. Fifty such samples were collected at each of four stages in the process. The aerobic bacteria, coliforms, and Escherichia coli recovered from each sample were enumerated. Values for the mean log units and standard deviations of each set of 50 log values were calculated on the assumption that the log values were normally distributed. The log of the arithmetic mean was estimated from the mean log and standard deviation values for each set. The results show that the average numbers of E. coli, coliforms, and aerobic bacteria which are deposited on carcasses during skinning and evisceration are not reduced by trimming, and that washing approximately halves the average numbers of those bacteria on carcasses. It is concluded that commercial trimming and washing operations are not effective means of decontaminating beef carcasses.

An analysis of the mechanics of phonation

1965 ◽  
Vol 20 (2) ◽  
pp. 301-307 ◽  
Author(s):  
G. A. Cavagna ◽  
R. Margaria
Keyword(s):  
Sound Production ◽  
Respiratory Muscles ◽  
Sound Intensity ◽  
Sound Level ◽  
Intensity Level ◽  
Elastic Recoil ◽  
Mechanical Models ◽  
Fine Regulation ◽  
Flow Through ◽  
Work Done

The mechanical work done by the chest in phonation has been measured together with the sound intensity level. The regulation of the sound intensity is done by regulating the intrapulmonary pressure. This is achieved at high intensity levels through the activity of the respiratory muscles that, together with the elastic recoil of the chest, sustain the work of phonation. At sound intensities below a critical level an additional mechanism for changing the intensity is given by a fine regulation of the opening of the glottis, thus allowing more air to escape without contributing to sound production. The contribution of the respiratory muscles, of the chest elasticity, and of the opening of the glottis to phonation at different intensity levels depend on the degree of inflation of the chest. The efficiency of phonation, as of sound production in mechanical models, seems to increase with increasing intensity and pitch. voice production; work done by chest during phonation; mechanical models of glottis generator; subglottic pressure as a function of sound level; air flow through glottis during phonation; efficiency changes of sound production; variation of sound intensity by regulating opening of glottis; variations of the area of glottis depending on extent of elastic recoil of chest Submitted on February 10, 1964

scholarly journals Silent oceans: ocean acidification impoverishes natural soundscapes by altering sound production of the world's noisiest marine invertebrate

2016 ◽  
Vol 283 (1826) ◽  
pp. 20153046 ◽  
Author(s):  
Tullio Rossi ◽  
Sean D. Connell ◽  
Ivan Nagelkerken
Keyword(s):  
Ocean Acidification ◽  
Sound Production ◽  
Marine Invertebrate ◽  
Empirical Test ◽  
Sound Level ◽  
Similar Reduction ◽  
Snapping Shrimp ◽  
Larval Stages ◽  
Coastal Marine ◽  
Ecological Importance

Soundscapes are multidimensional spaces that carry meaningful information for many species about the location and quality of nearby and distant resources. Because soundscapes are the sum of the acoustic signals produced by individual organisms and their interactions, they can be used as a proxy for the condition of whole ecosystems and their occupants. Ocean acidification resulting from anthropogenic CO 2 emissions is known to have profound effects on marine life. However, despite the increasingly recognized ecological importance of soundscapes, there is no empirical test of whether ocean acidification can affect biological sound production. Using field recordings obtained from three geographically separated natural CO 2 vents, we show that forecasted end-of-century ocean acidification conditions can profoundly reduce the biological sound level and frequency of snapping shrimp snaps. Snapping shrimp were among the noisiest marine organisms and the suppression of their sound production at vents was responsible for the vast majority of the soundscape alteration observed. To assess mechanisms that could account for these observations, we tested whether long-term exposure (two to three months) to elevated CO 2 induced a similar reduction in the snapping behaviour (loudness and frequency) of snapping shrimp. The results indicated that the soniferous behaviour of these animals was substantially reduced in both frequency (snaps per minute) and sound level of snaps produced. As coastal marine soundscapes are dominated by biological sounds produced by snapping shrimp, the observed suppression of this component of soundscapes could have important and possibly pervasive ecological consequences for organisms that use soundscapes as a source of information. This trend towards silence could be of particular importance for those species whose larval stages use sound for orientation towards settlement habitats.

Study on Combing Machine Based on Promotion Display Materials

2013 ◽  
Vol 340 ◽  
pp. 21-24
Author(s):  
Xuan Ren
Keyword(s):  
Technological Innovation ◽  
High Speed ◽  
Industrial Structure ◽  
Effective Means ◽  
Added Value ◽  
High Count

The comber equipment is essential for high-count yarn textile of the enterprises spun. It is an effective means to enhance the quality of the yarn, to adjust the industrial structure, to increase the added value of yarn, and to enhance the competitiveness. Currently, there is a gap between the domestic combers with world leading level. The article describes the technical characteristics of the domestic high-speed Comber and technological innovation, and focuses its network promotion display and the application.

scholarly journals Smartphone Addiction and Life Satisfaction: Mediating Effects of Sleep Quality and Self-Health

2021 ◽  
Vol 13 (3) ◽  
pp. 8
Author(s):  
Jianfei CAO ◽  
Yeongjoo Lim ◽  
Kota Kodama
Keyword(s):  
Life Satisfaction ◽  
Physical Fitness ◽  
Sleep Quality ◽  
Effective Means ◽  
Smartphone Addiction ◽  
Mediating Effects ◽  
Japanese University ◽  
The Relationship

As the popularity of smartphones grows, so does the number of people who are addicted to them. Although many studies have indicated that the various problems associated with smartphone addiction can negatively affect life satisfaction, this result is not absolute. This study surveyed 114 Chinese alumni of a Japanese university and analyzed the mediating effects of sleep quality and self-health on the relationship between smartphone addiction and life satisfaction.  Results indicated that smartphone addiction did not affect life satisfaction, neither directly nor indirectly through sleep quality and self-health. This finding was different from those of previous studies. In addition, the results indicated that smartphone addiction directly affects sleep quality, and that smartphone addiction can affect self-health either directly or indirectly through sleep quality. Based on this finding, we believe that intervention in the excessive use of smartphones is an effective means to improve the physical fitness of people.

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