About nonlinear nonspherical oscillations of a gas bubble in an incompressible ideal liquid

2003 ◽  
Vol 3 ◽  
pp. 178-194
Author(s):  
M.A. Ilgamov ◽  
E.Sh. Nasibullaeva ◽  
D.V. Kondtratyev
Keyword(s):  
Parametric Analysis ◽  
Applied Pressure ◽  
Pressure Change ◽  
Ideal Liquid ◽  
System Of Equations ◽  
Pressure Amplitude ◽  
Gas Bubble ◽  
Initial Radius ◽  
Initial Deviation ◽  
Incompressible Ideal Fluid

A comparative parametric analysis of a system of equations describing the nonspherical oscillations of a gas bubble in an incompressible ideal fluid is performed. The terms up to a second order of smallness in the amplitude of the surface perturbation are taking into account. Numerical calculations of this system of equations for various parameters (initial deviation from the sphere, pressure amplitude, initial radius) and for various laws of the applied pressure change are carried out.

Acoustic Characteristics of Simulated Respiratory-Induced Vocal Tremor

2013 ◽  
Vol 22 (2) ◽  
pp. 205-211 ◽  
Author(s):  
Rosemary A. Lester ◽  
Brad H. Story
Keyword(s):  
Healthy Adult ◽  
Forced Oscillation ◽  
Applied Pressure ◽  
Pressure Change ◽  
Adult Males ◽  
Acoustic Characteristics ◽  
Mean Intensity ◽  
The Mean ◽  
Vocal Tremor ◽  
Pressure Modulation

Purpose The purpose of this study was to investigate the relation of respiratory forced oscillation to the acoustic characteristics of vocal tremor. Method Acoustical analyses were performed to determine the characteristics of the intensity and fundamental frequency (F 0 ) for speech samples obtained by Farinella, Hixon, Hoit, Story, and Jones (2006) using a respiratory forced oscillation paradigm with 5 healthy adult males to simulate vocal tremor involving respiratory pressure modulation. The analyzed conditions were sustained productions of /a/ with amplitudes of applied pressure of 0, 1, 2, and 4 cmH 2 O and a rate of 5 Hz. Results Forced oscillation of the respiratory system produced modulation of the intensity and F 0 for all participants. Variability was observed between participants and conditions in the change in intensity and F 0 per unit of pressure change, as well as in the mean intensity and F 0 . However, the extent of modulation of intensity and F 0 generally increased as the applied pressure increased, as would be expected. Conclusion These findings suggest that individuals develop idiosyncratic adaptations to pressure modulations, which are important to understanding aspects of variability in vocal tremor, and highlight the need to assess all components of the speech mechanism that may be directly or indirectly affected by tremor.

Sealing performance test for V-insert clamp applicable to automobile exhaust pipes

2013 ◽  
Vol 227 (10) ◽  
pp. 2228-2235 ◽  
Author(s):  
Sung Ho Yoon ◽  
Young Eun Hwang
Keyword(s):  
Performance Test ◽  
Gradual Increase ◽  
Applied Pressure ◽  
Pressure Change ◽  
Testing System ◽  
Clamping Force ◽  
Automobile Exhaust ◽  
Sealing Performance ◽  
Applied Torque ◽  
Test Increase

The sealing performance of V-insert clamp used in automobile exhaust pipes was examined for various applied torques by a specially designed pneumatic testing system. Axial clamping forces of V-insert clamp were evaluated through a clamping performance test. In the clamping performance test, increase in the torque showed gradual increase in the axial clamping force for all gaps between exhaust pipes that were considered. Slight increase in the torque resulted in relatively high axial clamping force. In the sealing performance test, when applied pressure was 50 kPa, the leak was not present in all applied torques due to no pressure change as a function of time. For 100 kPa, the leak was observed for applied torques of 3 N-m and lower. When V-insert clamp was used to join the pipes together, at least the applied torque of 4 N-m was needed in order for V-insert clamp to effectively function in the exhaustion system. Therefore, it can be concluded that V-insert clamp showed sufficient sealing performance to support the applied pressure of up to 100 kPa within the exhaustion system when relatively high torque was applied.

Intrauterine pressure wave-form characteristics of spontaneous first stage labor

1975 ◽  
Vol 38 (3) ◽  
pp. 443-448 ◽  
Author(s):  
J. Seitchik ◽  
M. L. Chatkoff
Keyword(s):  
Pressure Wave ◽  
Total Duration ◽  
Pressure Change ◽  
Wave Form ◽  
Pressure Amplitude ◽  
Mean Values ◽  
Intrauterine Pressure ◽  
Start Up ◽  
Maximal Pressure ◽  
The Relationship

Intrauterine pressure wave-form parameters were measured in 827 contractions obtained from 26 patients in spontaneous labor. The coefficients of correlation between the maximal and minimal rates of pressure change and the maximal pressure amplitude were 0.78 and 0.63, respectively, and greater than or equal to 0.70 in 22/26 patients. Contractions partitioned into decile statistical groups of the pressure amplitude and both maximal and minimal rates. A linear relationship between these parameters has therefore been established. Contractions of greater amplitude tend to be longer, but the relationship between duration and amplitude is nonlinear with a limiting maximum contraction time. The duration of the midportion of the pressure wave appears invariate with respect to wave amplitude and only start-up and termination times increase with increasing amplitude. Mean values and standard deviations of the maximal amplitude (40.4 +/- 16.9mmHg). the maximal (2.4 +/- 0.9 mmHg/s) and minimal (-2.1+/- 0.9 mmHg/s)rates of pressure change, and the total duration of contractions (68.6 +/- 17.8s) were determined.

Pressure Change and Gas Mixing Induced by Oscillations in a Closed System

1985 ◽  
Vol 107 (1) ◽  
pp. 68-76 ◽  
Author(s):  
D. Isabey ◽  
A. Harf ◽  
H. K. Chang
Keyword(s):  
Pressure Change ◽  
Resonance Phenomenon ◽  
High Frequency Oscillation ◽  
Rigid Sphere ◽  
Straight Tube ◽  
Closed Volume ◽  
Pressure Amplitude ◽  
Convective Mixing ◽  
Gas Compression ◽  
Small Tube

In an attempt to delineate some mechanical behaviors found in branching airways, pressure transmission, gas motion, and mixing were studied during high-frequency oscillation (HFO) in an idealized system consisting of a large straight tube and a rigid sphere linked together by a small straight tube. Depending on the frequency f, and on the unsteadiness dimensionless parameter α, pressure amplitude in the large tube is either strongly attenuated or amplified in the sphere. This finding may provide a theoretical basis for the pressure resonance phenomenon observed in the lung by previous investigators. Gas compression in the closed volume causes convective mixing throughout the system. The measured dispersion was found to be proportional to f(VT/A)2, in agreement with a recent report. However, bulk convective mixing was sufficient to explain the dispersion for oscillatory volumes (VT) as small as 80 percent of the small tube volume, as has been previously suggested.

scholarly journals RHYTHMICITY IN THE PROTOPLASMIC STREAMING OF A SLIME MOLD, PHYSARUM POLYCEPHALUM

1958 ◽  
Vol 41 (6) ◽  
pp. 1223-1244 ◽  
Author(s):  
Uichiro Kishimoto
Keyword(s):  
Electric Potential ◽  
Atmospheric Pressure ◽  
Applied Pressure ◽  
Pressure Change ◽  
External Pressure ◽  
Slime Mold ◽  
Protoplasmic Streaming ◽  
Protoplasmic Movement ◽  
Made In

The electric potential difference (1 to 15 mv.) between two loci of the slime mold connected with a strand of protoplasm changes rhythmically with the same period (60 to 180 seconds) as that of back and forth protoplasmic streaming along the strand. When atmospheric pressure at a part of the plasmodium is increased (about 10 cm. H2O), the electric potential at this part becomes positive (0 to 20 mv.) to another part with a time constant of 2 to 15 minutes. If the atmospheric pressure at a part of the plasmodium is changed (about 10 cm. H2O) periodically, the electric potential rhythm also changes with the same period as that of the applied pressure change, and the amplitude of the former grows to a new level (i.e., forced oscillation). The electric potential rhythm, in this case, is generally delayed about 90° in phase angle from the external pressure change. The period of the electric potential rhythm which coincided with that of the pressure change is maintained for a while after stopping the application of the pressure change, if the period is not much different from the native flow rhythm. Such a pressure effect is brought about by the forced transport of protoplasm and is reversible as a rule. In the statistical analysis made by Kishimoto (1958) and in the rheological treatment made in the report, the rhythmic deformation of the contractile protein networks is supposed to be the cause of the protoplasmic flow along the strand and of the electric potential rhythm. The role of such submicroscopic networks in the protoplasm in various kinds of protoplasmic movement is emphasized.

Heart Rate Signal Decomposition

2000 ◽  
Vol 39 (02) ◽  
pp. 200-203
Author(s):  
H. Mizuta ◽  
K. Yana
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Pressure Change ◽  
Normal Subjects ◽  
Signal Decomposition ◽  
Large Individual ◽  
Heart Rate Fluctuations ◽  
Type Pattern ◽  
Signal Cancellation ◽  
Pressure Changes

Abstract:This paper proposes a method for decomposing heart rate fluctuations into background, respiratory and blood pressure oriented fluctuations. A signal cancellation scheme using the adaptive RLS algorithm has been introduced for canceling respiration and blood pressure oriented changes in the heart rate fluctuations. The computer simulation confirmed the validity of the proposed method. Then, heart rate fluctuations, instantaneous lung volume and blood pressure changes are simultaneously recorded from eight normal subjects aged 20-24 years. It was shown that after signal decomposition, the power spectrum of the heart rate showed a consistent monotonic 1/fa type pattern. The proposed method enables a clear interpretation of heart rate spectrum removing uncertain large individual variations due to the respiration and blood pressure change.

Canonical Submersion and Lie Homomorphisms Normal Subgroup

2020 ◽  
Vol 23 (1) ◽  
pp. 97-101
Author(s):  
Mikhail Petrichenko ◽  
Dmitry W. Serow
Keyword(s):  
Normal Subgroup ◽  
Canonical System ◽  
System Of Equations ◽  
Core Group ◽  
The Core ◽  
Switch Group

Normal subgroup module f (module over the ring F = [ f ] 1; 2-diffeomorphisms) coincides with the kernel Ker Lf derivations along the field. The core consists of the trivial homomorphism (integrals of the system v = x = f (t; x )) and bundles with zero switch group Lf , obtained from the condition ᐁ( ω × f ) = 0. There is the analog of the Liouville for trivial immersion. In this case, the core group Lf derivations along the field replenished elements V ( z ), such that ᐁz = ω × f. Hence, the core group Lf updated elements helicoid (spiral) bundles, in particular, such that f = ᐁU. System as an example Crocco shown that the canonical system does not permit the trivial embedding: the canonical system of equations are the closure of the class of systems that permit a submersion.

LIQUIDUS THERMO-BAROMETER FOR THE MODELING OF MAGNETITE — MELT EQUILIBRIUM

2018 ◽  
pp. 71-80
Author(s):  
N. S. Aryaeva ◽  
E. V. Koptev-Dvornikov ◽  
D. A. Bychkov
Keyword(s):  
Experimental Data ◽  
Liquidus Temperature ◽  
Vertical Structure ◽  
Maximum Error ◽  
Silicate Melt ◽  
System Of Equations ◽  
Wide Range ◽  
Basaltic Melts ◽  
Multidimensional Statistics

A system of equations of thermobarometer for magnetite-silicate melt equilibrium was obtained by method of multidimensional statistics of 93 experimental data of a magnetite solubility in basaltic melts. Equations reproduce experimental data in a wide range of basalt compositions, temperatures and pressures with small errors. Verification of thermobarometers showed the maximum error in liquidus temperature reproducing does not exceed ±7 °C. The level of cumulative magnetite appearance in the vertical structure of Tsypringa, Kivakka, Burakovsky intrusions predicted with errors from ±10 to ±50 m.

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