THE CORNWALL ISLAND PROJECT

1962 ◽  
Vol 16 (5) ◽  
pp. 243-247
Author(s):  
R. E. Moore

Analysis of results obtained by the photogrammetric methods used in the Cornwall Island project showed that the average mean square errors of position of control points was about 13 microns and the mean square error of short distances 6 microns, measured in the plane of the negative.

2018 ◽  
Vol 15 (4) ◽  
pp. 526-537
Author(s):  
A. M. Askhabov ◽  
E. S. Voevodin ◽  
V. A. Zeer ◽  
A. S. Kashura

Introduction. The purpose of the research is the determination of parameters and characteristics of the laser measuring systems providing decrease in errors of measurement of geometrical parameters of vehicles.The goal is achieved at the expense of the solution of the relevant task connected with the parameters research of the laser equipment and definition of requirements to accuracy (a passport error) of the laser range finders applied at geometrical parameters control of vehicles.Methods and materials. The algorithm of calculation of spatial coordinates of the car points and errors of their definition has been created and used for the research. In this case calculations of spatial provision of the point and its error have been reduced to definition and to the solution of the equations system of the second order in the MathCAD program environment. As the controlled and measured parameters at coordinates’ calculation of distances from laser measuring instruments to the studied car points were accepted.Results. As aresult, the mean square error of measurement of distance between control points significantly decreases at reduction of the passport error of laser range finders. At the size of the passport error of laser range finders equals 0,8 mm, the mean square error of measurement of distance between control points (from 0 to 3000 mm) equals 2,2-2,9 mm, and an error of definition of the control point is 1,5-1,9 mm.Discussion and conclusion. The conducted research demonstrates that it is necessary to compare the reached accuracy parameters at the set configuration of laser measuring system with the shown standard restrictions for an error of measurements. Therefore, further improvement of characteristics of accuracy of measuring systems is possible due to progressive decrease in an error of laser range finders as a result of their technical improvement.


2021 ◽  
Vol 971 (5) ◽  
pp. 2-9
Author(s):  
M.J. Bryn ◽  
Yu.V. Lobanova ◽  
D.A. Afonin ◽  
G.G. Shevshenko

The accuracy of determining the points’ position through the free stationing method is estimated. At performing alignment work, surveying facades, executive surveys, and geodetic monitoring of buildings and structures, the method of free stationing with an electronic total station installed in any suitable place and determining its position by serif, and then using the polar method, defi ning the coordinates of the determined point is considered. The accuracy assessment is identifi ed using the formulas of calculating the mean square error for the direct and reverse angular serifs, as well as for linear ones. The authors propose algorithms of accuracy evaluation for the located point positions with non-fi xed stationing method based on the parametric adjustment, and searching ones, at the same time the algorithms shall provide adjustment by considering or ignoring the errors in the input data. To determine the mean square error of the standing point’s position and the determined points according to the results of adjustment by the free stationing method, fi eld experimental studies were carried out. Numerical examples of accuracy evaluation are provided. The compliance of the adjustment results and root-mean-square errors will mean the validity of the proposed algorithms and accuracy of the performed survey.


1978 ◽  
Vol 48 ◽  
pp. 227-228
Author(s):  
Y. Requième

In spite of important delays in the initial planning, the full automation of the Bordeaux meridian circle is progressing well and will be ready for regular observations by the middle of the next year. It is expected that the mean square error for one observation will be about ±0.”10 in the two coordinates for declinations up to 87°.


2018 ◽  
Vol 934 (4) ◽  
pp. 59-62
Author(s):  
V.I. Salnikov

The question of calculating the limiting values of residuals in geodesic constructions is considered in the case when the limiting value for measurement errors is assumed equal to 3m, ie ∆рred = 3m, where m is the mean square error of the measurement. Larger errors are rejected. At present, the limiting value for the residual is calculated by the formula 3m√n, where n is the number of measurements. The article draws attention to two contradictions between theory and practice arising from the use of this formula. First, the formula is derived from the classical law of the normal Gaussian distribution, and it is applied to the truncated law of the normal distribution. And, secondly, as shown in [1], when ∆рred = 2m, the sums of errors naturally take the value equal to ?pred, after which the number of errors in the sum starts anew. This article establishes its validity for ∆рred = 3m. A table of comparative values of the tolerances valid and recommended for more stringent ones is given. The article gives a graph of applied and recommended tolerances for ∆рred = 3m.


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1631
Author(s):  
Bruno Guilherme Martini ◽  
Gilson Augusto Helfer ◽  
Jorge Luis Victória Barbosa ◽  
Regina Célia Espinosa Modolo ◽  
Marcio Rosa da Silva ◽  
...  

The application of ubiquitous computing has increased in recent years, especially due to the development of technologies such as mobile computing, more accurate sensors, and specific protocols for the Internet of Things (IoT). One of the trends in this area of research is the use of context awareness. In agriculture, the context involves the environment, for example, the conditions found inside a greenhouse. Recently, a series of studies have proposed the use of sensors to monitor production and/or the use of cameras to obtain information about cultivation, providing data, reminders, and alerts to farmers. This article proposes a computational model for indoor agriculture called IndoorPlant. The model uses the analysis of context histories to provide intelligent generic services, such as predicting productivity, indicating problems that cultivation may suffer, and giving suggestions for improvements in greenhouse parameters. IndoorPlant was tested in three scenarios of the daily life of farmers with hydroponic production data that were obtained during seven months of cultivation of radicchio, lettuce, and arugula. Finally, the article presents the results obtained through intelligent services that use context histories. The scenarios used services to recommend improvements in cultivation, profiles and, finally, prediction of the cultivation time of radicchio, lettuce, and arugula using the partial least squares (PLS) regression technique. The prediction results were relevant since the following values were obtained: 0.96 (R2, coefficient of determination), 1.06 (RMSEC, square root of the mean square error of calibration), and 1.94 (RMSECV, square root of the mean square error of cross validation) for radicchio; 0.95 (R2), 1.37 (RMSEC), and 3.31 (RMSECV) for lettuce; 0.93 (R2), 1.10 (RMSEC), and 1.89 (RMSECV) for arugula. Eight farmers with different functions on the farm filled out a survey based on the technology acceptance model (TAM). The results showed 92% acceptance regarding utility and 98% acceptance for ease of use.


2011 ◽  
Vol 57 (7) ◽  
pp. 4622-4635 ◽  
Author(s):  
Bernhard G. Bodmann ◽  
Pankaj K. Singh

2021 ◽  
pp. 58-60
Author(s):  
Naziru Fadisanku Haruna ◽  
Ran Vijay Kumar Singh ◽  
Samsudeen Dahiru

In This paper a modied ratio-type estimator for nite population mean under stratied random sampling using single auxiliary variable has been proposed. The expression for mean square error and bias of the proposed estimator are derived up to the rst order of approximation. The expression for minimum mean square error of proposed estimator is also obtained. The mean square error the proposed estimator is compared with other existing estimators theoretically and condition are obtained under which proposed estimator performed better. A real life population data set has been considered to compare the efciency of the proposed estimator numerically.


2010 ◽  
Vol 40 (8) ◽  
pp. 1844-1847 ◽  
Author(s):  
Dimas Estrasulas de Oliveira ◽  
Luis Orlindo Tedeschi

Saturated aliphatic hydrocarbons (n-alkanes) were extracted from feed, orts, and bovine fecal samples using disposable, plastic 5mL-syringes as an alternative material to disposable columns, which are normally used in the liquid-solid extraction phase of n-alkanes. For both methods, the n-alkane extracts (carbon chain length between 31 and 36 atoms) were identified using gas chromatography. The linear regression between methods were: 1) feces: column Alkane=2.63+0.92×syringeAlkane [r²=0.94, square root of the mean square error (RMSE)=13.7mg kg-1, n=30] from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively; 2) feeds: column Alkane=0.36+1.12×syringeAlkane (r²=0.85, RMSE=1.9mg kg-1, n=21) from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively; 3) orts: column Alkane=0.49+0.92×syringeAlkane (r²=0.98, RMSE=1.2mg kg-1, n=15) from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively. Materials with low concentration of n-alkanes may affect the values obtained in both methods. These results suggested that disposable plastic syringes might be a viable alternative to columns thus, reducing analytical costs.


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