Acoustical measuring instruments over the years

1980 ◽  
Vol 68 (1) ◽  
pp. 64-69
Author(s):  
Warren R. Kundert
Keyword(s):  
Measuring Instruments ◽  
Acoustical Measuring

Combined measuring equipment for testing acoustical measuring instruments in air

1974 ◽  
Vol 17 (7) ◽  
pp. 1063-1066
Author(s):  
D. Z. Lopashev ◽  
A. V. Kon'kov ◽  
S. V. Kuznetsov
Keyword(s):  
Measuring Equipment ◽  
Measuring Instruments ◽  
Acoustical Measuring

Concept of a new PZT

1978 ◽  
Vol 48 ◽  
pp. 271-278
Author(s):  
Chr. Kühne
Keyword(s):  
Mirror System ◽  
Measuring Instruments

The PZT according to MARKOWITZ, undoubtedly one of the most accurate measuring instruments, has become an integral part of astronomy in the last years. Yet there are two reasons why I still tried to improve the MARKOWITZ basic idea.For the MARKOWITZ process the use of a lens objective is imperative. Because of the diameter limitations of the lens objectives the magnitude is reduced. Although a 65 cm PZT has been put into operation in Washington recently, the thermal difficulties encountered made it necessary to control the temperature actively. In addition, the 65 cm diameter of a lens equipped with 4 elements can be considered as the very limit, but not for a mirror system.In addition there are still more disadvantages using lens objectives. The useable field is restricted by astigmatism, reducing the range of declination. The transmission, especially in the blue wavelengths, decreases very rapidly with the thickness of lenses. For large multilens objectives the transmission is less than for a mirror system.

Mathematical simulation of error functions of decision-making at tolerance control of measuring techniques availability

Metrologiya ◽  
2020 ◽  
pp. 3-15
Author(s):  
Rustam Z. Khayrullin ◽  
Alexey S. Kornev ◽  
Andrew A. Kostoglotov ◽  
Sergey V. Lazarenko
Keyword(s):  
Measurement Error ◽  
Geometric Interpretation ◽  
Measuring Instruments ◽  
Measured Quantity ◽  
Metrological Examination ◽  
Technical Documentation ◽  
Error Functions ◽  
Measuring Techniques ◽  
Tolerance Control ◽  
Laws Of Distribution

Analytical and computer models of false failure and undetected failure (error functions) were developed with tolerance control of the parameters of the components of the measuring technique. A geometric interpretation of the error functions as two-dimensional surfaces is given, which depend on the tolerance on the controlled parameter and the measurement error. The developed models are applicable both to theoretical laws of distribution, and to arbitrary laws of distribution of the measured quantity and measurement error. The results can be used in the development of metrological support of measuring equipment, the verification of measuring instruments, the metrological examination of technical documentation and the certification of measurement methods.

Method of estimation of hidden correlation of narrowband noise signals

2019 ◽  
pp. 34-39 ◽  
Author(s):  
E.I. Chernov ◽  
N.E. Sobolev ◽  
A.A. Bondarchuk ◽  
L.E. Aristarhova
Keyword(s):  
Signal Processing ◽  
Digital Signal Processing ◽  
New Technology ◽  
Digital Signal ◽  
Measuring Instruments ◽  
Central Frequency ◽  
Pearson Criterion ◽  
Useful Signal ◽  
Band Limited ◽  
Narrowband Noise

The concept of hidden correlation of noise signals is introduced. The existence of a hidden correlation between narrowband noise signals isolated simultaneously from broadband band-limited noise is theoretically proved. A method for estimating the latent correlation of narrowband noise signals has been developed and experimentally investigated. As a result of the experiment, where a time frag ent of band-limited noise, the basis of which is shot noise, is used as the studied signal, it is established: when applying the Pearson criterion, there is practically no correlation between the signal at the Central frequency and the sum of signals at mirror frequencies; when applying the proposed method for the analysis of the same signals, a strong hidden correlation is found. The proposed method is useful for researchers, engineers and metrologists engaged in digital signal processing, as well as developers of measuring instruments using a new technology for isolating a useful signal from noise – the method of mirror noise images.

Status and development prospects of standard means for reproducing units of volumetric activity of radon and thoron and radon flux density from the soil surface

2020 ◽  
pp. 69-73
Author(s):  
S.G. Birjukov ◽  
O.I. Kovalenko ◽  
A.A. Orlov
Keyword(s):  
Flux Density ◽  
Soil Surface ◽  
National Standards ◽  
Measuring Instruments ◽  
Volumetric Activity ◽  
Standard Means ◽  
Radon Flux ◽  
Technical Solutions ◽  
Development Prospects ◽  
Physical Principles

The approach to creating standard means for reproducing units of volumetric activity of radon and thoron and flux density of radon from the soil surface is described based on the physical principles of reproducing these units of quantities and using as technical means for reproducing bubblers with a radioactive solution of radium salt, reference capacities of known volume, emanation chambers for generation of a toron, a gamma spectrometer with a semiconductor detector from highly pure germanium and radon radiometers. Reproduction consists in the physical realization of units in accordance with their definition as applied to the formation of radon and thoron in the radioactive rows of radium and thorium. The proposed approach will allow to determine the structural, structural and other technical solutions of standard measuring instruments, as well as specific techniques and methods of working with them. The creation of standard tools and technologies for reproducing units of volumetric activity of radon and thoron and the density of radon flux from the soil surface will ensure the unity and reliability of measurements in the field of ionizing radiation, traceability of units and bringing the characteristics of national standards in line with world achievements.

Playful activities in the learning of geometric notions in children of initial, Callao

2019 ◽  
Vol 1 (1) ◽  
pp. 22
Author(s):  
Carla Marilia Ayala Valladares ◽  
Juana Maria Cruz Montero ◽  
Angel Saldarriaga Melgar
Keyword(s):  
Experimental Design ◽  
Favorable Effect ◽  
Measuring Instruments ◽  
Geometric Shapes ◽  
Geometric Figures ◽  
Quasi Experimental ◽  
Probabilistic Sample

The main purpose of the research was to determine the effects of the program of ludic activities for the learning of geometry in children of five years in all their dimensions orientation and location, geometric shapes and measurement, through its components: location in space, identify locations and positions of objects, identify and characterize geometric figures and communicate the qualities of these, likewise identify, classify magnitudes and use various measuring instruments. The type of research was applied, with a quasi-experimental design, the population was constituted by 103 children, and a non-probabilistic sample was used for convenience with a sample of 51 children, divided into two control and experimental groups. The geometry instrument was used to collect information. The favorable effect of the program of playful activities in the learning of geometric notions in children of initial - Callao, 2018 was determined.

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