scholarly journals Sine-wave Amplitude Coding Using A Mixed LSF/Parcor Representation

2005 ◽  
Author(s):  
R.B. Dunn ◽  
R.J. McAuiay ◽  
T.G. Champion ◽  
E. Singer ◽  
T.F. Quatieri
Keyword(s):  
Wave Amplitude ◽  
Sine Wave

scholarly journals Accurate Sine-Wave Amplitude Measurements Using Nonlinearly Quantized Data

2015 ◽  
Vol 64 (12) ◽  
pp. 3201-3208 ◽  
Author(s):  
Paolo Carbone ◽  
Johan Schoukens ◽  
Istvan Kollar ◽  
Antonio Moschitta
Keyword(s):  
Wave Amplitude ◽  
Sine Wave

scholarly journals Accuracy of DTFT-based Sine-wave Amplitude Estimators

2018 ◽  
Vol 1065 ◽  
pp. 052030
Author(s):  
Daniel Belega ◽  
Dario Petri ◽  
Dominique Dallet
Keyword(s):  
Wave Amplitude ◽  
Sine Wave

Correlating resting discharge with small signal sensitivity and discharge variability in primary endings of cat soleus muscle spindles

1994 ◽  
Vol 71 (1) ◽  
pp. 309-316 ◽  
Author(s):  
J. J. Scott ◽  
J. E. Gregory ◽  
U. Proske ◽  
D. L. Morgan
Keyword(s):  
Soleus Muscle ◽  
Wave Amplitude ◽  
Muscle Length ◽  
Muscle Spindles ◽  
Sine Wave ◽  
Small Signal ◽  
Signal Sensitivity ◽  
Maximum Body ◽  
Maximum Body Length ◽  
Conditioning Contraction

1. In a previous report we proposed that primary endings of cat soleus muscle spindles can be separated into two kinds. One kind, called by us silent endings, at muscle lengths shorter than Lm -10 (maximum body length -10 mm), fell silent after a 5 mm shortening step. Spontaneous endings, on the other hand, were able to resume a resting discharge after a brief pause at all muscle lengths down to Lm -20. This report examines further differences between the two kinds of endings. 2. There were consistent differences in the muscle length dependence of the maintained level of resting discharge of the two kinds of endings, measured after a conditioning contraction or a contraction followed by a shortening step. The resting discharge of spindles with spontaneous endings, after both forms of conditioning increased progressively with length. For silent endings, after a conditioning contraction, resting discharge fell slightly at longer lengths. 3. Discharge variability, measured at a number of muscle lengths, showed a dependence both on mean interimpulse interval and on spindle type, being higher in silent than spontaneous spindles. 4. Small signal sensitivity was measured with the use of 1 Hz sinusoidal stretches applied longitudinally to the tendon. Sine wave amplitude was adjusted to give a 30% depth of modulation of the resting discharge. Spontaneous endings were consistently less sensitive to the stretches than silent endings at all muscle lengths. Average sensitivities, measured over a range of lengths between Lm -4 and Lm -20 mm were 0.30 imp.s-1.microns -1 for spontaneous endings and 0.66 imp.s-1.microns -1 for silent endings.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Effects of Cyclic Loading on the Pore Structure of Anthracite Coal

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Dong Wang ◽  
Tie Li ◽  
Zhiheng Cheng ◽  
Weihua Wang
Keyword(s):  
Cyclic Loading ◽  
Hydraulic Fracturing ◽  
Pore Structure ◽  
Wave Amplitude ◽  
Testing Machine ◽  
Sine Wave ◽  
Shanxi Province ◽  
Loading Frequency ◽  
Anthracite Coal ◽  
Pulse Hydraulic Fracturing

In the process of improving coalbed permeability through pulse hydraulic fracturing, the cyclic loading effect influences the characteristics of micropores in coal matrix, thus affecting the process of gas migration. Therefore, it is essential to investigate the effect of cyclic loading on the pore structure of coal. Seven groups of loading tests at different frequencies and amplitudes were conducted on anthracite coal obtained from Shanxi Province, China, using a fatigue-testing machine. Subsequently, using a PoreMaster GT-60 Mercury-intrusion apparatus, the influence of the frequency and amplitude on the structural characteristics (including mercury-injection and mercury-ejection curves, pore size distribution, porosity, and specific surface area) of pores in coal samples was analyzed. Finally, the law and mechanism of action of the loading frequency and amplitude on pores in coal samples were comprehensively analyzed. The test results showed that, in the case of maintaining the sine-wave amplitude unchanged during loading while altering the loading frequency, the overall porosity and pore volume rise at different degrees. The growth of the loading frequency presents a more significant promotive effect on the initiation and development of pores and fractures. Moreover, it drives the transformation of micropores and transition pores into mesopores and macropores, thus increasing the proportion of seepage pores. Under the condition of large sine-wave amplitude during loading, macropores and mesopores are subjected to the repeated action of the external force, thereby reducing the overall porosity. In addition, the volume of the seepage pores declines, and the number of the coalesced pores decreases. Finally, in light of these results, the implications of frequency and amplitude selection in the process of pulse hydraulic fracturing are discussed. Therefore, the results of this research will provide an important theoretical basis for the field application of pulse hydraulic fracturing technology in coal mines.

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