scholarly journals GEODESY, CARTOGRAPHY, AND AERIAL PHOTOGRAPHY

2021 ◽  
Vol 93,2021 (93) ◽  
pp. 13-26
Author(s):  
Ihor Trevoho ◽  
◽  
Fedir Zablotskyi ◽  
Andrzej Piskorek ◽  
Bohdan Dzhuman ◽  
...  
Keyword(s):  
High Precision ◽  
Practical Significance ◽  
Control Points ◽  
Mean Square ◽  
Border Area ◽  
Height System ◽  
Geodynamic Processes ◽  
The Mean ◽  
The Baltic ◽  
Two Stages

Purpose. The purpose of this work is obtaining connections between the Baltic and European height systems based on the I class leveling between the Ukrainian and Polish control points of the base vertical networks and construction of the quasigeoid surface on the border area. Method. Full integration of the hight system of Ukraine into the European vertical reference system (EVRS) consists of two stages: modernization of the height network of Ukraine through its integration into the United European leveling network UELN; construction and use as a regional vertical date the model of high-precision quasigeoid, which will be consistent with the European geoid EGG2015. The analysis of methods of high-precision leveling in Ukraine and Poland, and also the analysis of methods of construction of quasigeoid models in these countries is performed. Results. For integrating the Ukrainian hight system into the UELN/EVRS2000 system, the Ukrainian side performed I class geometric leveling along two lines: Lviv - Shehyni - Przemysl and Kovel - Yagodyn - Chelm with total length of 196 km. The root mean square systematic error on both lines of leveling was s<0.01 mm/km. In turn, the mean square random error along the line Lviv - Shehyni - Przemysl is h=0.29 mm/km, and along the line Kovel - Yagodyn - Chelm is h=0.27 mm/km. For double control on the cross-border part, the Polish side performed high-precision leveling with a length of 33 km. The differences between the Ukrainian and Polish leveling in all sections are within the tolerance. The analysis of influence of geodynamic phenomena on control of high-precision leveling is carried out. GNSS-leveling was performed on all fundamental and ground benchmarks, as well as horizontal marks. These measurements were used to build a quasigeoid model for the border area of Ukraine. The MSE of the obtained quasigeoid model is about 2 cm, which corresponds to the accuracy of the input information. Scientific novelty and practical significance. The connection of the Ukrainian and European height systems will ensure Ukraine’s integration into the European economic system, participation in international research of global ecological and geodynamic processes, study of the Earth’s shape and gravitational field and mapping of Ukraine using navigational and remote-sensing satellite technologies. Calculation of a high-precision model of a quasigeoid on the Ukraine area in relation to the European height system, agreed with the European geoid EGG2015, will allow to obtain gravity-dependent heights using modern satellite technologies.

scholarly journals GEODESY, CARTOGRAPHY, AND AERIAL PHOTOGRAPHY

2021 ◽  
Vol 93,2021 (93) ◽  
pp. 27-34
Author(s):  
Kornyliy Tretyak ◽  
◽  
Ivan Brusak ◽  
Keyword(s):  
High Precision ◽  
Practical Significance ◽  
Control Points ◽  
Mean Square ◽  
Border Area ◽  
Height System ◽  
Geodynamic Processes ◽  
The Mean ◽  
The Baltic ◽  
Two Stages

Purpose. The purpose of this work is obtaining connections between the Baltic and European height systems based on the I class leveling between the Ukrainian and Polish control points of the base vertical networks and construction of the quasigeoid surface on the border area. Method. Full integration of the hight system of Ukraine into the European vertical reference system (EVRS) consists of two stages: modernization of the height network of Ukraine through its integration into the United European leveling network UELN; construction and use as a regional vertical date the model of high-precision quasigeoid, which will be consistent with the European geoid EGG2015. The analysis of methods of high-precision leveling in Ukraine and Poland, and also the analysis of methods of construction of quasigeoid models in these countries is performed. Results. For integrating the Ukrainian hight system into the UELN/EVRS2000 system, the Ukrainian side performed I class geometric leveling along two lines: Lviv - Shehyni - Przemysl and Kovel - Yagodyn - Chelm with total length of 196 km. The root mean square systematic error on both lines of leveling was s<0.01 mm/km. In turn, the mean square random error along the line Lviv - Shehyni - Przemysl is h=0.29 mm/km, and along the line Kovel - Yagodyn - Chelm is h=0.27 mm/km. For double control on the cross-border part, the Polish side performed high-precision leveling with a length of 33 km. The differences between the Ukrainian and Polish leveling in all sections are within the tolerance. The analysis of influence of geodynamic phenomena on control of high-precision leveling is carried out. GNSS-leveling was performed on all fundamental and ground benchmarks, as well as horizontal marks. These measurements were used to build a quasigeoid model for the border area of Ukraine. The MSE of the obtained quasigeoid model is about 2 cm, which corresponds to the accuracy of the input information. Scientific novelty and practical significance. The connection of the Ukrainian and European height systems will ensure Ukraine’s integration into the European economic system, participation in international research of global ecological and geodynamic processes, study of the Earth’s shape and gravitational field and mapping of Ukraine using navigational and remote-sensing satellite technologies. Calculation of a high-precision model of a quasigeoid on the Ukraine area in relation to the European height system, agreed with the European geoid EGG2015, will allow to obtain gravity-dependent heights using modern satellite technologies.

scholarly journals ASSESSMENT OF INFLUENCE OF RANGE FINDERS WITH THE IMPROVED CHARACTERISTICS ON THE ACCURACY OF GEOMETRICAL PARAMETERS CONTROL OF VEHICLES

2018 ◽  
Vol 15 (4) ◽  
pp. 526-537
Author(s):  
A. M. Askhabov ◽  
E. S. Voevodin ◽  
V. A. Zeer ◽  
A. S. Kashura
Keyword(s):  
Mean Square Error ◽  
Geometrical Parameters ◽  
Control Points ◽  
Mean Square ◽  
Measuring Systems ◽  
Laser Range ◽  
Laser Range Finders ◽  
The Mean ◽  
Definition Of ◽  
Error Of Measurement

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.

scholarly journals On the accuracy of (quasi) geoid models relatively UELN/EVRS2000 height systems

2021 ◽  
Vol 41 (I) ◽  
pp. 29-36
Author(s):  
F. ZABLOTSKYY ◽  
◽  
B. DZHUMAN ◽  
I. BRUSAK ◽  
◽  
...  
Keyword(s):  
Gravitational Field ◽  
High Precision ◽  
Zero Point ◽  
Border Region ◽  
Geoid Model ◽  
Static Mode ◽  
Earth’S Gravitational Field ◽  
Starting Point ◽  
Height System ◽  
The Baltic

Nowadays the Baltic Height System 1977 operates in Ukraine, the starting point of which is the zero of the Kronstadt banchmark. However, the current height system in Ukraine is morally obsolete primarily due to the great distance from the zero-point of height (about 2 thousand km) and the difficulty of adapting to the use of satellite surveying methods. Therefore, today it does not correspond to the level of development of modern geospatial technologies and it needs to be modernized. The most optimal way to modernize the height network of Ukraine is its integration into the United European Leveling Network UELN, the zero point of which is the Amsterdam banchmark. Within the framework of such integration it is necessary to create a high-precision geoid model for the territory of Ukraine, connected to the UELN/EVRS2000 height system. Aim. The purpose of the work is to compare the accuracy of different geoid/quasigeoid models and the global gravitational field of the Earth on the Western Ukraine area (border region) relative to the heights of points in the height system UELN/EVRS2000, where GNSSleveling is performed, and to determine the most optimal model in relation to which a high-precision geoid model can be created, consistent with the UELN/EVRS2000 height system.Method. To obtain the heights of leveling points on the Ukraine area in the UELN/EVRS2000 height system we performed I class leveling on two lines from the fundamental benchmarks on the territory of Ukraine (heights are known in the Baltic height system 1977) to I class benchmarks on the Poland area (UELN/EVRS2000 height system). GNSS-leveling in static mode (1-second sampling observations for more than 6 hours) was performed on all fundamental and ground benchmarks, as well as horizontal marks. Results. The heights of the quasigeoid at 26 points are obtained from the performed measurements. The heights are compared with three global models of the Earth’s gravitational field: EGM2008, EIGEN-6C4 and XGM2019e_2159 (the maximum order of all these models is 2190), as well as with the European geoid EGG2015. It is established that the best accuracy (≈ 7 cm) allows to obtain the European geoid EGG2015. Scientific novelty and practical significance. For the first time the accuracy of the Earth’s gravitational field models and geoid models on the Ukraine area is investigated at points where the height in the UELN/EVRS2000 height system is known. We established that when constructing a high-precision quasigeoid using the “Remove–Restore” procedure, it is best to use the European geoid EGG2015 as a systematic component.

THE CORNWALL ISLAND PROJECT

1962 ◽  
Vol 16 (5) ◽  
pp. 243-247
Author(s):  
R. E. Moore
Keyword(s):  
Mean Square Error ◽  
Control Points ◽  
Mean Square ◽  
Analysis Of Results ◽  
The Mean ◽  
Mean Square Errors

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.

The Bordeaux Automatic Meridian Circle

1978 ◽  
Vol 48 ◽  
pp. 227-228
Author(s):  
Y. Requième
Keyword(s):  
Mean Square Error ◽  
Mean Square ◽  
Meridian Circle ◽  
The Mean ◽  
Full Automation

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°.

The mean-square generalized delayed decision feedback sequence detector

2003 ◽  
Vol 14 (3) ◽  
pp. 265-268 ◽  
Author(s):  
Maurizio Magarini ◽  
Arnaldo Spalvieri ◽  
Guido Tartara
Keyword(s):  
Decision Feedback ◽  
Mean Square ◽  
The Mean

Limit tolerances for sums of measurement errors

2018 ◽  
Vol 934 (4) ◽  
pp. 59-62
Author(s):  
V.I. Salnikov
Keyword(s):  
Normal Distribution ◽  
Mean Square Error ◽  
Gaussian Distribution ◽  
Measurement Errors ◽  
Theory And Practice ◽  
Mean Square ◽  
The Mean ◽  
Limiting Values ◽  
Limiting Value

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.

scholarly journals A High-Precision Registration Technology Based on Bundle Adjustment in Structured Light Scanning System

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jianying Yuan ◽  
Qiong Wang ◽  
Xiaoliang Jiang ◽  
Bailin Li
Keyword(s):  
High Precision ◽  
Large Scale ◽  
Structured Light ◽  
Bundle Adjustment ◽  
Scanning System ◽  
Control Points ◽  
Registration Method ◽  
Global Control ◽  
3D Data ◽  
Structured Light Scanning

The multiview 3D data registration precision will decrease with the increasing number of registrations when measuring a large scale object using structured light scanning. In this paper, we propose a high-precision registration method based on multiple view geometry theory in order to solve this problem. First, a multiview network is constructed during the scanning process. The bundle adjustment method from digital close range photogrammetry is used to optimize the multiview network to obtain high-precision global control points. After that, the 3D data under each local coordinate of each scan are registered with the global control points. The method overcomes the error accumulation in the traditional registration process and reduces the time consumption of the following 3D data global optimization. The multiview 3D scan registration precision and efficiency are increased. Experiments verify the effectiveness of the proposed algorithm.

scholarly journals Electrical stimulator with mechanomyography-based real-time monitoring, muscle fatigue detection, and safety shut-off: a pilot study

2020 ◽  
Vol 65 (4) ◽  
pp. 461-468
Author(s):  
Jannatul Naeem ◽  
Nur Azah Hamzaid ◽  
Amelia Wong Azman ◽  
Manfred Bijak
Keyword(s):  
Muscle Fatigue ◽  
Real Time ◽  
Isometric Force ◽  
Mean Square ◽  
Clear Indication ◽  
Initial Value ◽  
Cord Injury ◽  
The Mean ◽  
Electrical Stimulator ◽  
Fatigue Detection

AbstractFunctional electrical stimulation (FES) has been used to produce force-related activities on the paralyzed muscle among spinal cord injury (SCI) individuals. Early muscle fatigue is an issue in all FES applications. If not properly monitored, overstimulation can occur, which can lead to muscle damage. A real-time mechanomyography (MMG)-based FES system was implemented on the quadriceps muscles of three individuals with SCI to generate an isometric force on both legs. Three threshold drop levels of MMG-root mean square (MMG-RMS) feature (thr50, thr60, and thr70; representing 50%, 60%, and 70% drop from initial MMG-RMS values, respectively) were used to terminate the stimulation session. The mean stimulation time increased when the MMG-RMS drop threshold increased (thr50: 22.7 s, thr60: 25.7 s, and thr70: 27.3 s), indicating longer sessions when lower performance drop was allowed. Moreover, at thr70, the torque dropped below 50% from the initial value in 14 trials, more than at thr50 and thr60. This is a clear indication of muscle fatigue detection using the MMG-RMS value. The stimulation time at thr70 was significantly longer (p = 0.013) than that at thr50. The results demonstrated that a real-time MMG-based FES monitoring system has the potential to prevent the onset of critical muscle fatigue in individuals with SCI in prolonged FES sessions.

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