On choosing the laser tracker stations location for installation of technological equipment

2019 ◽  
Vol 953 (11) ◽  
pp. 22-25
Author(s):  
L.E. Serdakov ◽  
P.P. Murzincev ◽  
D.B. Burenkov ◽  
А.V. Polianskiy
Keyword(s):  
Review Article ◽  
Precision Measurements ◽  
Process Equipment ◽  
Laser Tracker ◽  
Technological Equipment ◽  
Vertical Angle ◽  
Closed Ring ◽  
Alignment Process ◽  
The Mean ◽  
Mean Square Errors

A review article on the alignment of technological equipment located on a closed ring path (for example cyclic accelerators). Such geodesic works are very difficult, since the tolerance for alignment in the radial and altitude directions is 0,05 mm. The main survey instrument in such works is a laser tracker. The positions of the laser tracker stations were studied during equipment alignment, taking into account the effect of errors in the transverse directions. The values of the mean square errors for the distances and angles of the API trackers are used. Calculations are made for distances from 0,5 to 10 meters usual for production of precision measurements. The cases of installation of a laser tracker outside and inside the project radius are considered. The results of error calculations when changing the vertical angle of the laser tracker are also presented. The obtained results enable determining the 3D zones for the alignment process equipment, which will improve the efficiency of geodetic works.

On optimization of geodetic reference networks of accelerators using laser trackers

2017 ◽  
Vol 923 (5) ◽  
pp. 2-6
Author(s):  
P.P. Murzincev ◽  
А.V. Polianskiy ◽  
L.E. Serdakov
Keyword(s):  
Geodetic Network ◽  
Geometric Parameters ◽  
Design Stage ◽  
Laser Tracker ◽  
Technological Equipment ◽  
Mean Square ◽  
Geodetic Networks ◽  
Reference Networks ◽  
Mean Square Errors ◽  
Laser Trackers

The features of laser tracker measurements and their accounting for designing geodetic networks on the accelerator complexes are considered. The key parameters for the optimization of the spatial geodetic network of the accelerator are proposed. The dependence of average mean square errors on the radial and altitudinal directions of orientation of the sighting beam for distances from 1 to 30 meters was defined. The influence of the choice of stations for mounting the laser tracker to determine the parameters of the ellipsoid of errors was studied. The measurements for three variants of geodetic networks in the tunnel with the adopted geometric parameters were simulated. The data of the deviations of the points of the network radius, altitude relative to the project was indicated. The obtained results can be useful both at the design stage of geodetic network accelerator, and at the stage of installation of technological equipment.

scholarly journals Digit Variability in Carotenoid Scores Obtained with the Veggie Meter: A Pilot Study (P02-001-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Velarie Ansu ◽  
Stephanie Dickinson ◽  
Alyce Fly
Keyword(s):  
Indiana University ◽  
Left Hand ◽  
Funding Sources ◽  
Right Hand ◽  
Period Data ◽  
The Mean ◽  
The Right ◽  
Post Hoc ◽  
Main Effects ◽  
Mean Square Errors

Abstract Objectives To determine which digit and hand have the highest and lowest skin carotenoid scores, to compare inter-and-intra-hand variability of digits, and to determine if results are consistent with another subject. Methods Two subjects’ first(F1), second(F2), third(F3) and fifth(F5) digits on both hands were measured for skin carotenoids with a Veggie Meter, for 3 times on each of 18 days over a 37-day period. Data were subjected to ANOVA in a factorial treatment design to determine main effects for hand (2 levels), digits (4), and days (18) along with interactions. Differences between digits were determined by Tukey's post hoc test. Results There were significant hand x digit, hand x day, digit x day, and hand x digit x day interactions and significant simple main effects for hand, digit, and day (all P < 0.001). Mean square errors were 143.67 and 195.62 for subject A and B, respectively, which were smaller than mean squares for all main effects and interactions. The mean scores ± SD for F1, F2, F3, and F5 digits for the right vs left hands for subject A were F1:357.13 ± 45.97 vs 363.74 ± 46.94, F2:403.17 ± 44.77 vs. 353.20 ± 44.13, F3:406.76 ± 43.10 vs. 357.11 ± 45.13, and F5:374.95 ± 53.00 vs. 377.90 ± 47.38. For subject B, the mean scores ± SD for digits for the right vs left hands were F1:294.72 ± 61.63 vs 280.71 ± 52.48, F2:285.85 ± 66.92 vs 252.67 ± 67.56, F3:268.56 ± 57.03 vs 283.22 ± 45.87, and F5:288.18 ± 34.46 vs 307.54 ± 40.04. The digits on the right hand of both subjects had higher carotenoid scores than those on the left hands, even though subjects had different dominant hands. Subject A had higher skin carotenoid scores on the F3 and F2 digits for the right hand and F5 on the left hand. Subject B had higher skin carotenoid scores on F5 (right) and F1 (left) digits. Conclusions The variability due to hand, digit, and day were all greater than that of the 3 replicates within the digit-day for both volunteers. This indicates that data were not completely random across the readings when remeasuring the same finger. Different fingers displayed higher carotenoid scores for each volunteer. There is a need to conduct a larger study with more subjects and a range of skin tones to determine whether the reliability of measurements among digits of both hands is similar across the population. Funding Sources Indiana University.

scholarly journals What Have We Learned from Empirical Studies of Unemployment Insurance?

ILR Review ◽  
1979 ◽  
Vol 33 (1) ◽  
pp. 95-95
Keyword(s):  
Uniform Distribution ◽  
Unemployment Insurance ◽  
Total Population ◽  
Empirical Studies ◽  
Policy Research ◽  
Review Article ◽  
Coverage Rate ◽  
Unemployment Duration ◽  
Waiting Period ◽  
The Mean

TIMOTHY J. CARR of Mathematica Policy Research, Inc. has brought to our attention an error in an example provided by Finis Welch in his July 1977 Review article, “What Have We Learned from Empirical Studies of Unemployment Insurance?” On page 459 Welch stated that under his assumptions (of a uniform distribution of unemployment duration from zero to twenty weeks and a two-week waiting period), the mean duration among those not receiving benefits, given an 80 percent coverage rate, would be six weeks. Actually, with an 80 percent coverage rate, the mean duration would be 7.43 weeks. According to Welch, this can be verified by the following calculations: With fraction, C, of the population covered and with 10 percent of covered employees not receiving benefits, the fraction of the total population not receiving benefits is [Formula: see text] and expected or mean duration is [Formula: see text] So, with C = 0.8, expected duration is (10.0 − 7.92) / (1 − .72) = 2.08/.28 = 7.43. EDITOR

scholarly journals Identification power line sections with increased electricity losses using sensors with Wi-Fi technology for data transmission

2020 ◽  
Vol 178 ◽  
pp. 01083 ◽  
Author(s):  
Igor Nikolaevich Fomin ◽  
Roman Pavlovich Belikov ◽  
Tatyana Anatolyevna Kudinova ◽  
Alexei Nikolaevich Tsvetkov
Keyword(s):  
Power Supply ◽  
Data Transmission ◽  
Agricultural Production ◽  
Power Supply System ◽  
Distribution Networks ◽  
Supply System ◽  
Technological Equipment ◽  
Ring Network ◽  
Closed Ring ◽  
Operational Diagnostics

Modern highly mechanized and electrified agriculture places high demands on power supply reliability and uninterrupted work. To increase the reliability of power supply to agricultural consumers, in some cases, taking into account the configuration of electric distribution networks and the availability of responsible consumers, a conditionally closed ring network is created. Interruptions in power supply lead to downtime of agricultural production, a decrease in the volume of output, damage to the main technological equipment [1, 2]. In this regard, there is a need to make informed decisions on the choice of ways to increase the reliability of uninterrupted power supply due to the reservation of various elements of the power supply system, improving the organization of maintenance, and the operational diagnostics of faulty elements.

scholarly journals Approach to the construction of specialized portable terminals for monitoring and controlling technological equipment

2018 ◽  
Vol 224 ◽  
pp. 01089 ◽  
Author(s):  
Petr Nikishechkin ◽  
Nadezhda Chervonnova ◽  
Anatoly Nikich
Keyword(s):  
Human Computer Interaction ◽  
Machine Tools ◽  
Process Equipment ◽  
Technological Equipment ◽  
Machining Center ◽  
Complex Process ◽  
Computer Interaction

The work deals with the features of construction of human-computer interaction to manage the complex process equipment. The mechanism for creating additional portable terminals for monitoring and controlling complex machine tools is presented. A practical example of using the mechanism for creating additional terminal solutions for monitoring and controlling the Quaser MV184P milling machining center is given.

scholarly journals Realization of the Primary Terrestrial Reference Frame

1991 ◽  
Vol 127 ◽  
pp. 108-115
Author(s):  
W. Kosek ◽  
B. Kołaczek
Keyword(s):  
Reference Frame ◽  
Geographic Distribution ◽  
Terrestrial Reference Frame ◽  
Mean Square ◽  
Minimum Value ◽  
Collocation Points ◽  
Station Coordinates ◽  
The Mean ◽  
Transformation Parameters ◽  
Mean Square Errors

AbstractThe PTRF is based on 43 sites with 64 SSC collocation points with the optimum geographic distribution, which were selected from all stations of the ITRF89 according to the criterion of the minimum value of the errors of 7 parameters of transformation. The ITRF89 was computed by the IERS Terrestrial Frame Section in Institut Geographique National - IGN and contains 192 VLBI and SLR stations (points) with 119 collocation ones. The PTRF has been compared with the ITRF89. The errors of the 7 parameters of transformation between the PTRF and 18 individual SSC as well as the mean square errors of station coordinates are of the same order as those for the ITRF89. The transformation parameters between the ITRF89 and the PTRF are negligible and their errors are of the order of 3 mm.

Mathematical-Statistical Methods for the Analysis of Aerial Triangulation Adjustment Errors Using a Computer Program

1975 ◽  
Vol 29 (2) ◽  
pp. 175-188
Author(s):  
M. Mosaad Allam
Keyword(s):  
Computer Program ◽  
Frequency Interval ◽  
Mean Square ◽  
Fisher Criterion ◽  
Statistical Parameters ◽  
Sample Distribution ◽  
Development Section ◽  
The Mean ◽  
Kolmogorov Criterion ◽  
Mean Square Errors

In practice, photogrammetrists use a single statistic reliability interval criterion, based on the mean square errors, to judge the accuracy of adjustment of photogrammetric blocks. Even in some cases, if the practical and theoretical distributions of frequency interval agree, such a test does not make it possible to establish the closeness of their convergence nor the degree of their difference. In other words, to get a complete picture of the character of the distribution of errors in the adjusted photogrammetric blocks, it is insufficient to investigate any single statistic. In the Research and Development Section of the Topographical Survey Directorate, a computer program (SABA) has been designed to analyze the errors of photogrammetric block adjustments, compute various statistical parameters and check the sample distribution using Kolmogorov criterion. Based on the decision taken, the correspondence between the empirical and theoretical distribution series are checked using the criterion χ2. The program divides the adjusted block to make a comparative evaluation of accuracies in the different sub-blocks. In this case, in addition to Kolmogorov and χ2 tests, the program checks the reliability intervals of the means and mean square errors of the samples and uses Fisher criterion ‘F’ to check the hypothesis of the equality of dispersion. SABA is coded in Fortran IV and Compass for the CDC CYBER 74 and requires a central memory of 28K decimal works. SABA is the acronym for Statistical Analysis of Block Adjustment.

Extrapolation Problem for Continuous Time Periodically Correlated Isotropic Random Fields

2017 ◽  
Vol 19 ◽  
pp. 1-23
Author(s):  
Iryna Golichenko ◽  
Oleksand Masyutka ◽  
Mikhail Moklyachuk
Keyword(s):  
Random Field ◽  
Spectral Characteristics ◽  
Mean Square ◽  
Spectral Densities ◽  
Optimal Linear ◽  
Extrapolation Problem ◽  
Time Argument ◽  
The Mean ◽  
Mean Square Errors ◽  
Isotropic Random

The problem of optimal linear estimation of functionals depending on the unknown values of a random fieldζ(t,x), which is mean-square continuous periodically correlated with respect to time argumenttє R and isotropic on the unit sphere Sn with respect to spatial argumentxєSn. Estimates are based on observations of the fieldζ(t,x) +Θ(t,x) at points (t,x) :t< 0;xєSn, whereΘ(t,x) is an uncorrelated withζ(t,x) random field, which is mean-square continuous periodically correlated with respect to time argumenttє R and isotropic on the sphereSnwith respect to spatial argumentxєSn. Formulas for calculating the mean square errors and the spectral characteristics of the optimal linear estimate of functionals are derived in the case of spectral certainty where the spectral densities of the fields are exactly known. Formulas that determine the least favourable spectral densities and the minimax (robust) spectral characteristics are proposed in the case where the spectral densities are not exactly known while a class of admissible spectral densities is given.

Application of Photoelectric Sensor in Vehicle Power Control System

2020 ◽  
Vol 15 (6) ◽  
pp. 700-706
Author(s):  
Yifan Zhao ◽  
Mengyu Wang ◽  
Kai Wang
Keyword(s):  
Power Control ◽  
Electric Energy ◽  
Least Square Method ◽  
Least Square ◽  
Motor Speed ◽  
Time Calculation ◽  
The Mean ◽  
The Difference ◽  
Artificial Neural Network Ann ◽  
Mean Square Errors

Due to its characteristics of using clean electric energy and bringing no damage to the environment, electric vehicles (EVs) have become a new developmental direction for the automotive industry. Its reliability issues have also attracted the attention of experts and professionals. In the field of automotive power control, from the perspective of motor control, this study uses the photoelectric sensors (PSs) as the research objects and elaborates on the measurement principles of motor speed with PSs. Meanwhile, a diagnosis scheme is proposed for various faults in the measurement. Among them, the measurement speed is converted by the photoelectric signal, and the measured waveform is amplified. In the fault detection process, the Radial Basis Function (RBF) artificial neural network (ANN) is analyzed. By using this method, the difference in the motor speed detected by the sensor is calculated to determine the cause of the failure. The test uses the least-square method to compare the tested motor speed with the actual motor speed. The results show that PSs can measure the motor speed of EVs. As for the motor failures, the mean square errors (MSEs) of motor speeds generated by different faults are compared to determine the fault points according to the speed changes. In addition, the cause of motor failure can be determined by the real-time calculation of the speed differences. The above tests fully prove the effectiveness of measuring the speed of electric motors by PSs; therefore, PSs have broad application prospects in vehicle power control systems.

scholarly journals A validation study of reconstructed rapid prototyping models produced by two technologies

2017 ◽  
Vol 87 (5) ◽  
pp. 782-787 ◽  
Author(s):  
Christian Andreas Dietrich ◽  
Andreas Ender ◽  
Stefan Baumgartner ◽  
Albert Mehl
Keyword(s):  
Rapid Prototyping ◽  
Validation Study ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Comparative Assessment ◽  
Precision Measurements ◽  
Mean Deviation ◽  
The Mean ◽  
Dimensional Errors ◽  
Stereolithographic Models

ABSTRACT Objective: To determine the accuracy (trueness and precision) of two different rapid prototyping (RP) techniques for the physical reproduction of three-dimensional (3D) digital orthodontic study casts, a comparative assessment using two 3D STL files of two different maxillary dentitions (two cases) as a reference was accomplished. Materials and Methods: Five RP replicas per case were fabricated using both stereolithography (SLA) and the PolyJet system. The 20 reproduced casts were digitized with a highly accurate reference scanner, and surface superimpositions were performed. Precision was measured by superimposing the digitized replicas within each case with themselves. Superimposing the digitized replicas with the corresponding STL reference files assessed trueness. Statistical significance between the two tested RP procedures was evaluated with independent-sample t-tests (P &lt; .05). Results: The SLA and PolyJet replicas showed statistically significant differences for trueness and precision. The precision of both tested RP systems was high, with mean deviations in stereolithographic models of 23 (±6) μm and in PolyJet replicas of 46 (±13) μm. The mean deviation for trueness in stereolithographic replicas was 109 (±4) μm, while in PolyJet replicas, it was 66 (±14) μm. Conclusions: Comparing the STL reference files, the PolyJet replicas showed higher trueness than the SLA models. But the precision measurements favored the SLA technique. The dimensional errors observed in this study were a maximum of 127 μm. In the present study, both types of reproduced digital orthodontic models are suitable for diagnostics and treatment planning.

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