Computer modeling of evaluation of metrological characteristics of the measure of phase shift

Pages 2442–2454: A. D. McClellan and W. Jang, “Mechanosensory inputs to the central pattern generators for locomotion in the lamprey spinal cord: resetting, entrainment, and computer modeling.” The oscillator PRCs (Fig. 2 B) used in the computer simulations (Figs. 10—14) were inverted which was implemented by making the PRC scalars negative See PDF for Equation Thus synaptic inputs to an oscillator that produce phase delay (phase advance), which is represented by positive (negative) values in the PRCs in Fig. 2 B, will contribute a negative (positive) phase shift to the expression for oscillator phase ( Eq. 1) so that it takes a longer (shorter) time for the oscillator phase vector to complete one cycle.

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Computer modeling of the metrological characteristics ofγ-spectrometric radiation monitors

Atomic Energy ◽

10.1007/bf02407322 ◽

1995 ◽

Vol 78 (2) ◽

pp. 141-143

Author(s):

I. A. Gaponov ◽

G. V. Zykov ◽

A. M. Chernyaev ◽

S. I. Emel'yanov

Keyword(s):

Computer Modeling ◽

Metrological Characteristics ◽

Radiation Monitors

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МЕТОДИ І ЗАСОБИ АВТОМАТИЧНОГО ВИРІВНЮВАННЯ АМПЛІТУД ГАРМОНІЧНИХ СИГНАЛІВ В СИСТЕМАХ ВИМІРЮВАННЯ МАЛИХ ФАЗОВИХ ЗСУВІВ

Automation, Measuring and Management / Автоматика, вимірювання та керування ◽

10.23939/amm2020.01.001 ◽

2020 ◽

pp. 1-8

Author(s):

Ігор Бучма ◽

Keyword(s):

Computer Modeling ◽

Signal Amplitude ◽

Voltage Divider ◽

Metrological Characteristics ◽

Harmonic Signals ◽

Automatic Amplitude

The article considers the automatic amplitude equalizer of harmonic signals based on a controlled voltage divider, its computer modeling. The errors of signal amplitude alignment are estimated. Possible ways to improve the metrological characteristics of the equalizer are indicated.

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DEFINITION OF THE SHAFTS RADIAL BEATING CAPACITIVE SENSOR RESPONSE FUNCTION BY COMPUTER MODELING

Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini ◽

10.15407/publishing2021.58.107 ◽

2021 ◽

Vol 2021 (58) ◽

pp. 107-112

Author(s):

V.O. Bereznychenko ◽

Keyword(s):

Computer Modeling ◽

Response Function ◽

Capacitive Sensor ◽

Sensor Response ◽

Metrological Characteristics ◽

Element Analysis ◽

Modeling Tools ◽

Simulation Tools ◽

Simulation Results ◽

Definition Of

The paper presents the results study the characteristics of capacitive beating sensors to optimize them by computer simulation tools using. A concentric capacitive sensor with high-potential and grounded electrodes was studied. In the course of the research, the expediency of using computer modeling tools by finite element analysis methods to study the metrological characteristics of sensors was shown. It is shown that the application of modeling makes it possible to reduce the time spent on studies of the transformation function and metrological characteristics. The picture of the distribution of equipotential lines of an electric field in a working backlash of the sensor has resulted. The simulation results make it possible to create a picture of equipotential lines by changing the distance between the total surface of the sensor electrodes and the grounded surface, simulating the surface of the shaft. The results of the definition of the response function are given. References 23, figures 5.

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Object Wave Determination by Single-Sideband Methods

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071776 ◽

1973 ◽

Vol 31 ◽

pp. 266-267

Author(s):

Kenneth H. Downing ◽

Benjamin M. Siegel

Keyword(s):

Phase Shift ◽

Carbon Films ◽

Object Wave ◽

Electron Wave ◽

Phase Object ◽

Heavy Atoms ◽

Single Sideband ◽

Thin Carbon ◽

Additional Phase Shift ◽

Additional Phase

Under the “weak phase object” approximation, the component of the electron wave scattered by an object is phase shifted by π/2 with respect to the unscattered component. This phase shift has been confirmed for thin carbon films by many experiments dealing with image contrast and the contrast transfer theory. There is also an additional phase shift which is a function of the atomic number of the scattering atom. This shift is negligible for light atoms such as carbon, but becomes significant for heavy atoms as used for stains for biological specimens. The light elements are imaged as phase objects, while those atoms scattering with a larger phase shift may be imaged as amplitude objects. There is a great deal of interest in determining the complete object wave, i.e., both the phase and amplitude components of the electron wave leaving the object.

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A Many-Beam Technique for Enhanced Resolution of Partial Dislocations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096485 ◽

1972 ◽

Vol 30 ◽

pp. 646-647

Author(s):

J. M. Oblak ◽

B. H. Kear

Keyword(s):

Phase Shift ◽

Field Method ◽

Dark Field ◽

Bright Field ◽

Field Technique ◽

Weak Beam ◽

Partial Dislocations ◽

Enhanced Resolution ◽

Nickel Base ◽

Beam Technique

The “weak-beam” and systematic many-beam techniques are the currently available methods for resolution of closely spaced dislocations or other inhomogeneities imaged through strain contrast. The former is a dark field technique and image intensities are usually very weak. The latter is a bright field technique, but generally use of a high voltage instrument is required. In what follows a bright field method for obtaining enhanced resolution of partial dislocations at 100 KV accelerating potential will be described.A brief discussion of an application will first be given. A study of intermediate temperature creep processes in commercial nickel-base alloys strengthened by the Ll2 Ni3 Al γ precipitate has suggested that partial dislocations such as those labelled 1 and 2 in Fig. 1(a) are in reality composed of two closely spaced a/6 <112> Shockley partials. Stacking fault contrast, when present, tends to obscure resolution of the partials; thus, conditions for resolution must be chosen such that the phase shift at the fault is 0 or a multiple of 2π.

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Observation of surface morphology by reflection electron holography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154652 ◽

1989 ◽

Vol 47 ◽

pp. 536-537

Author(s):

N. Osakabe ◽

J. Endo ◽

T. Matsuda ◽

A. Tonomura

Keyword(s):

Phase Shift ◽

Surface Morphology ◽

High Sensitivity ◽

High Energy ◽

Path Difference ◽

Transmission Mode ◽

Electron Holography ◽

Dynamical Process ◽

High Vertical Resolution ◽

Amplification Technique

Progress in microscopy such as STM and TEM-TED has revealed surface structures in atomic dimension. REM has been used for the observation of surface dynamical process and surface morphology. Recently developed reflection electron holography, which employes REM optics to measure the phase shift of reflected electron, has been proved to be effective for the observation of surface morphology in high vertical resolution ≃ 0.01 Å.The key to the high sensitivity of the method is best shown by comparing the phase shift generation by surface topography with that in transmission mode. Difference in refractive index between vacuum and material Vo/2E≃10-4 owes the phase shift in transmission mode as shownn Fig. 1( a). While geometrical path difference is created in reflection mode( Fig. 1(b) ), which is measured interferometrically using high energy electron beam of wavelength ≃0.01 Å. Together with the phase amplification technique , the vertivcal resolution is expected to be ≤0.01 Å in an ideal case.

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