scholarly journals Comparison of form measurement results for optical aspheres and freeform surfaces

2022 ◽  
Author(s):  
Ines Fortmeier ◽  
Michael Schulz
Keyword(s):  
Measurement Data ◽  
Evaluation Procedure ◽  
3D Measurement ◽  
Measurement Point ◽  
Freeform Surfaces ◽  
Measurement Systems ◽  
Evaluation Strategies ◽  
Comparison Results ◽  
Measurement Results ◽  
Different Levels

Abstract Comparing form measurement data for aspheres and freeform surfaces is an important tool for ensuring the quality and functionality of the devices used to take such measurements and may also allow the underlying measurement methods to be evaluated. However, comparing the highly accurate form measurements of such complex surfaces is a demanding task. It is difficult to analyze measurement results whose accuracies are in the range of several tens of nanometers root-mean-square, especially when comparing data with different, and anisotropic distributions of the 3D measurement points on the surface under test. In this paper, we investigate eight different 3D measurement point distributions that are typical of highly accurate measurement systems currently in use and demonstrate the effects of these distributions on the comparison results by using virtually generated data and applying different evaluation strategies. The results show that, for the examples investigated, the different 3D measurement point distributions can yield different levels of accuracy for the comparison. Furthermore, an improved evaluation procedure is proposed and recommendations on how to significantly reduce the influence of the different 3D measurement point distributions on the comparison result are given. A method of employing virtually generated test data is presented that may be generalized in order to further improve and validate future comparison methods.

State special primary acceleration measurement standard for gravimetry GET 190-2019

2020 ◽  
pp. 3-8
Author(s):  
L.F. Vitushkin ◽  
F.F. Karpeshin ◽  
E.P. Krivtsov ◽  
P.P. Krolitsky ◽  
V.V. Nalivaev ◽  
...  
Keyword(s):  
High Precision ◽  
Free Fall ◽  
Measurement Range ◽  
Measurement Standard ◽  
Acceleration Measurement ◽  
Measurement Systems ◽  
Free Fall Acceleration ◽  
Investigation Methods ◽  
Measurement Results ◽  
Upper Level

The State special primary acceleration measurement standard for gravimetry (GET 190-2019), its composition, principle of operation and basic metrological characteristics are presented. This standard is on the upper level of reference for free-fall acceleration measurements. Its accuracy and reliability were improved as a result of optimisation of the adjustment procedures for measurement systems and its integration within the upgraded systems, units and modern hardware components. A special attention was given to adjusting the corrections applied to measurement results with respect to procedural, physical and technical limitations. The used investigation methods made it possibled to confirm the measurement range of GET 190-2019 and to determine the contributions of main sources of errors and the total value of these errors. The measurement characteristics and GET 90-2019 were confirmed by the results obtained from measurements of the absolute value of the free fall acceleration at the gravimetrical site “Lomonosov-1” and by their collation with the data of different dates obtained from measurements by high-precision foreign and domestic gravimeters. Topicality of such measurements ensues from the requirements to handle the applied problems that need data on parameters of the Earth gravitational field, to be adequately faced. Geophysics and navigation are the main fields of application for high-precision measurements in this field.

scholarly journals Modeling of German Low Voltage Cables with Ground Return Path

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1265 ◽  
Author(s):  
Johanna Geis-Schroer ◽  
Sebastian Hubschneider ◽  
Lukas Held ◽  
Frederik Gielnik ◽  
Michael Armbruster ◽  
...  
Keyword(s):  
Low Voltage ◽  
Measurement Data ◽  
Analytical Calculation ◽  
Laboratory Measurement ◽  
Model Parameters ◽  
Calculation Methods ◽  
Modeling Approach ◽  
Measurement Results ◽  
Simulation Results ◽  
Return Path

In this contribution, measurement data of phase, neutral, and ground currents from real low voltage (LV) feeders in Germany is presented and analyzed. The data obtained is used to review and evaluate common modeling approaches for LV systems. An alternative modeling approach for detailed cable and ground modeling, which allows for the consideration of typical German LV earthing conditions and asymmetrical cable design, is proposed. Further, analytical calculation methods for model parameters are described and compared to laboratory measurement results of real LV cables. The models are then evaluated in terms of parameter sensitivity and parameter relevance, focusing on the influence of conventionally performed simplifications, such as neglecting house junction cables, shunt admittances, or temperature dependencies. By comparing measurement data from a real LV feeder to simulation results, the proposed modeling approach is validated.

scholarly journals Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff
Keyword(s):  
Large Scale ◽  
Measurement Data ◽  
Fine Grained ◽  
Dredged Materials ◽  
Measurement Results ◽  
Large Scale Field ◽  
Eigenvalue Ratio ◽  
Ill Posed ◽  
Materials Used ◽  
Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

scholarly journals Methane Emission during Gas and Rock Outburst on the Basis of the Unipore Model

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1999 ◽  
Author(s):  
Skoczylas Norbert ◽  
Anna Pajdak ◽  
Katarzyna Kozieł ◽  
Leticia Teixeira Palla Braga
Keyword(s):  
Coal Mine ◽  
Effective Diffusion ◽  
Measurement Data ◽  
Sorption Isotherms ◽  
Sieve Analysis ◽  
Measurement Systems ◽  
Upper Silesian Coal Basin ◽  
Tectonic Disturbances ◽  
Concentration Changes ◽  
Time Courses

The goal of this paper is to analyze the phenomenon of gas emission during a methane and coal outburst based on the unipore Crank diffusion model for spherical grains and plane sheets. Two occurrences in the Upper Silesian Coal Basin were analyzed: an outburst in a Zofiówka coal mine in 2005 and an outburst in a Budryk coal mine in 2012. Those two outbursts differed considerably. The first one was connected with an unidentified tectonic disturbance in the form of a triple, interlocking fault, and the other one is an example of an outburst in an area free from tectonic disturbances. The model analysis required laboratory tests in order to determine the sorption properties of coals from post-outburst masses. Sorption isotherms and the values of the effective diffusion coefficient were specified. The post-outburst masses were subjected to sieve analysis and the grain composition curves were plotted. The researchers also used the measurement data provided by proper mine services, such as the methane content, the volume of post-outburst masses, and the time courses of CH4 concentration changes in excavations. They were recorded by methane measurement systems in the mines.

scholarly journals Measurement experiences with FluxSet digital D/I station

2017 ◽  
Vol 6 (2) ◽  
pp. 279-284 ◽  
Author(s):  
László Hegymegi ◽  
János Szöllősy ◽  
Csaba Hegymegi ◽  
Ádám Domján
Keyword(s):  
Measurement Method ◽  
Measurement Data ◽  
Digital Form ◽  
New Instrument ◽  
Measurement Results ◽  
Inclination Angles ◽  
Flux Gate

Abstract. Geomagnetic observatories use classical theodolites equipped with single-axis flux-gate magnetometers known as declination–inclination magnetometers (DIM) to determine absolute values of declination and inclination angles. This instrument and the measurement method are very reliable but need a lot of handwork and experience. The authors developed and built a non-magnetic theodolite which gives all measurement data in digital form. Use of this instrument significantly decreases the possibility of observation errors and minimises handwork. The new instrument is presented in this paper together with first measurement results in comparison to the classical DIM.

scholarly journals Prototype Sistem Deteksi Partial Discharge Pada Isolasi Kabel Menggunakan Sensor Microphone (Prototype Of Partial Discharge Detection System In Cable Isolation Using Microphone Sensor)

2019 ◽  
Vol 3 (2) ◽  
pp. 206
Author(s):  
Mochamad Zaeynuri Setiawan ◽  
Fachrudin Hunaini ◽  
Mohamad Mukhsim
Keyword(s):  
Detection System ◽  
Partial Discharge ◽  
Measurement Data ◽  
Negative Ions ◽  
High Sensitivity ◽  
Sound Waves ◽  
Cable Insulation ◽  
Insulation Failure ◽  
Measurement Results ◽  
Discharge Detection

The phenomenon that often arises in a substation is the problem of partial discharge in outgoing cable insulation. Partial discharge is a jump of positive and negative ions that are not supposed to meet so that it can cause a spark jump. If a partial discharge is left too long it can cause insulation failure, the sound of snakes like hissing and the most can cause a flashover on the outgoing cable. Then a partial discharge detection prototype was made in the cable insulation in order to anticipate the isolation interference in the outgoing cable. Can simplify the work of substation operators to check the reliability of insulation on the outgoing side of each cubicle. So it was compiled as a method for measuring sound waves caused by partial discharge in the process of measuring using a microphone sensor, the Arduino Mega 2560 module as a microcontroller, the LCD TFT as a monitoring and the MicroSD card module as its storage. The microphone sensor is a sensor that has a high sensitivity to sound, has 2 analog and digital readings, and is easily designed with a microcontroller. Basically the unit of measure measured at partial discharge is Decibels. The results of the prototype can be applied to the cubicle and the way it works is to match the prototype to the outgoing cubicle cable then measure from the cable boots connector to the bottom of the outgoing cable with a distance of 1 meter. Then the measurement results will be monitored on the TFT LCD screen in the form of measurement results, graphs and categories on partial discharge. In this design the measurement data made by the microphone can be stored with microSD so that it can make an evaluation of partial discharge handling in outgoing cable insulation.

scholarly journals Making roundness measurement applications and control systems on the Roundness Tester Machine

2019 ◽  
Vol 63 (3) ◽  
pp. 17-21
Author(s):  
Dodi Sofyan Arief ◽  
◽  
Eko Jadmiko ◽  
Adhy Prayitno ◽  
Muftil Badri ◽  
...  
Keyword(s):  
Control Systems ◽  
Measurement Data ◽  
Rotating Speed ◽  
Center Point ◽  
Global Quality ◽  
Measurement Results ◽  
Roundness Deviation ◽  
And Control ◽  
Dial Indicator ◽  
Roundness Measurement

Dial indicator is a comparison device usually used in industrial activities, especially in production. To make measurements at this time must be supported by technology that can facilitate operators when using it and when analyzing measurement results. Involving the programme and microcontroller are a solution to developing in roundness measurement, and then the results can be more accurate or thorough between the readable values read from the measuring instrument with the actual value of varying the amount of data. Roundness application is a program that can input measurement data automatically and can do calculations directly. Then, it can display a reference circle, a table that calculates the values of X, Y, R, X’, Y’, R’, Roundness Deviation, Run out Concentricity or a shift in the center point and also the center point shift or Theta. In measuring roundness, the test object is used the Standard Mandrel which has been certified by PT. Global Quality Indonesia, by determining three points or positions, namely in the first position the amount of data is 180, in the second position the amount of data is 90 and in the third position, the amount of data is 60 with a rotating speed of 15 mm/s. The results of the reference circle can be seen in each calculation in each position, in the second position the roundness deviation values are approaching of the Mandrel.

scholarly journals Using and Explaining Individual Dosimetry Data

2017 ◽  
Vol 29 (2_suppl) ◽  
pp. 110S-119S ◽  
Author(s):  
Makoto Miyazaki
Keyword(s):  
Nuclear Power ◽  
Large Scale ◽  
Measurement Data ◽  
Lessons Learned ◽  
Individual Dose ◽  
Protection Measures ◽  
Measurement Results ◽  
Individual Dosimetry ◽  
Dose Measurements ◽  
Self Protection

Measurement of individual radiation dose is crucial for planning protective measures after nuclear accidents. The purpose of this article is to explain the various initiatives taken after the TEPCO Fukushima Daiichi Nuclear Power Plant accident, including the D-shuttle project wherein residents from affected areas wore a personal dosimeter to measure their own external exposure. The experience in Fukushima revealed several issues such as gaining residents’ trust and ensuring appropriate communication of the measured data. The D-shuttle project also revealed that obtaining individual dose measurement data had 2 purposes, as the information obtained was to be utilized by the residents for self-protection and by the authorities for deriving the dose distribution of the population to aid in designing large-scale protection measures. The lessons learned are that both the residents and the authorities need to understand and share the meaning of individual dose measurements and the measurement results must be used with due respect for the residents’ privacy and other concerns.

Evolution of the Role of Measurement Systems in Industrial Decision Support

2016 ◽  
pp. 560-580 ◽  
Author(s):  
Miroslaw Staron ◽  
Wilhelm Meding ◽  
Kent Niesel ◽  
Ola Söder
Keyword(s):  
Decision Support ◽  
Data Collection ◽  
Decision Support Systems ◽  
Information Needs ◽  
Support Systems ◽  
Measurement Data ◽  
Automated Measurement ◽  
Measurement Systems ◽  
Distributed Decision

Measurement data can be used for decision support in multiple ways – from one-time, manual data collection/presentation (reporting) through flexible business intelligence solutions to online, automated measurement systems. In centralized organizations, the measurement data is often collected through reporting, but the trends in modern organizations with empowered teams, globalized development, and needs to monitor continuously longer supply chains requires shift in the design and use of measurement systems. In this chapter, we present a study of evolving measurement systems at three companies with global businesses – Ericsson, Volvo Cars, and Axis Communications. The results of the study include the identification of the timeline of the evolution, distinct generations of measurement systems and information needs in the different phases of the evolution. The experiences show how to evolve centralized decision support systems to support global and distributed decision support.

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