Re-Establishment and Maintenance of Geodetic Networks in Parts of Oyo State Using Modern Techniques

Oyo state like most of the other states in the Nigeria has an old and conventional Geodetic Network. This network was established and computed using the conventional method of position determination and the science of navigation in the 1930- 1950's which is based on the 30th arc-meridian of the Clarke 1880 modified ellipsoid with its origin at L40 Minna datum. This does not satisfy the overgrowing mapping requirements of the state and as well as other Geo-related information requirements. The required data were acquired with GNSS receivers set up on each of the existing points in static mode. The reference network that was re- established consists of eight (8) primary points, covering an area of approximately ?12km?^2 with an average separation of about 7Km. The new network monuments are made of reinforced concrete, solidly cemented in the ground with metal caps (brass markers), and coordinated using the static carrier phase differential GPS measurement. Several observation sessions were conducted and processed to compute 3D coordinates for the network. Post processed data were rigorously adjusted using Least Squares and must meet the distance accuracy specifications for a first order network (1:100,000). Final coordinates are based on WGS84 frame/ ITRF 2008 datum and are within a mean accuracy of ±0. 05m. Finally, the plots of the re-established control points were presented and thus re-established a reliable first order geodetic reference network within Oyo state. Based on the findings the study recommends all geodetic networks in Nigeria should be re- established.

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PECULIARITIES OF CONSTRUCTION OF GEODESIC NETWORK FOR DEVELOPMENT OF OPEN MINERAL DEPOSITS

Young Scientist ◽

10.32839/2304-5809/2020-11-87-3 ◽

2020 ◽

Vol 11 (87) ◽

Author(s):

Oksana Serant ◽

◽

Olena Kubrak ◽

Nataliia Yarema ◽

Maksym Batura ◽

...

Keyword(s):

Geodetic Network ◽

Cost Effective ◽

Weather Conditions ◽

Reference Network ◽

Satellite Measurement ◽

Geodetic Networks ◽

Advantages And Disadvantages ◽

Adverse Weather ◽

The Creation ◽

Combination Of Methods

The creation of geodetic networks for open deposits has its own characteristics, in contrast to the creation of conventional geodetic networks. Surveying networks of support points for groups of quarries and individual quarries located in developed mining regions, as well as in large industrial, hydraulic and agricultural structures adjacent to cities, are being developed on the basis of existing networks of higher-class triangulation points. In the absence of higher-class triangulation points, open source support networks are created independently. The study of geodetic monitoring in mining, especially in deposits that are developed in an open way. The design of geodetic reference networks depends entirely on the shape of the quarry and the system of its opening. According to its form, choose the method of creating a planned geodetic basis. For the most part, a backbone network is created to further condense and create a film network.After analyzing the methods of creating a spatial reference network for open deposits, we concluded that the classical methods of creating a planned-height geodetic network on the territory of the mining enterprise are time-consuming, long-term and economically unprofitable. The GNSS method is the best for creating such networks at present. Of course, it cannot fully replace all methods due to various constraints, such as interference, lack of communication, and adverse weather conditions. Therefore, given the advantages and disadvantages of the methods analyzed in the article to create spatial networks in open fields, the authors consider it appropriate to combine the GNSS method with polygonometry, as the use of only satellite measurement method is impractical, but in combination with polygonometry -altitude networks for geodetic works. This combination significantly reduces measurement time, is less time-consuming, cost-effective and meets the accuracy requirements of the relevant networks. Approbation of the combination of methods for the creation of a spatial geodetic network for monitoring the open field was carried out at the Vilnohirsk mining and metallurgical plant.

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Integration of the ASG-EUPOS Permanent Stations with First Order National Geodetic Networks - Measurements and Results

Artificial Satellites ◽

10.2478/v10018-012-0008-8 ◽

2011 ◽

Vol 46 (4) ◽

pp. 165-174 ◽

Cited By ~ 2

Author(s):

Leszek Jaworski ◽

Anna Swiatek ◽

Ryszard Zdunek ◽

Janusz Zielinski

Keyword(s):

Data Processing ◽

Data Acquisition ◽

Geodetic Network ◽

Processing Method ◽

Coordinate Frame ◽

First Order ◽

Geodetic Networks ◽

Data Processing Method ◽

Station Coordinates

Integration of the ASG-EUPOS Permanent Stations with First Order National Geodetic Networks - Measurements and ResultsThe ASG-EUPOS network - the active geodetic network was established in Poland in 2008. The 2010/2011 campaign was the second one managed to integrate the ASG-EUPOS network with the first order national geodetic networks in Poland. As the result the station coordinates were determined in the uniform coordinate frame. The paper describes the measurements carried out for data acquisition as well as the data processing method. The results present analyses of differences between selected variants of solutions and show some problems encountered during the calculation.

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EXPERIENCE OF USING PRACTICE OF LOCAL AUTOMATIZED GEODETIC NETWORKS BASED ON DOMESTIC GNSS RECEIVERS

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2019-1-1-28-35 ◽

2019 ◽

Vol 1 (1) ◽

pp. 28-35

Author(s):

Stanislav Shevchuk ◽

Vadim Ponomarev ◽

Elena Cheremisina ◽

Sergey Ivanov

Keyword(s):

Geodetic Network ◽

Relative Positioning ◽

Geodetic Networks ◽

Geotechnical Monitoring ◽

Gnss Receivers ◽

Made In

In article the local automatized geodetic network (MAGS) that provides RTK and post-processed relative positioning for geotechnical monitoring. The net based on using of GNSS receiv-ers and software which made in Russia. The results of practical tests are showed.

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Intermittent heat instabilities in an air plume

Nonlinear Processes in Geophysics ◽

10.5194/npg-23-319-2016 ◽

2016 ◽

Vol 23 (4) ◽

pp. 319-330

Author(s):

Jean-Louis Le Mouël ◽

Vladimir G. Kossobokov ◽

Frederic Perrier ◽

Pierre Morat

Keyword(s):

Temperature Sensors ◽

Time Varying ◽

First Order ◽

Spatial Function ◽

Universal Feature ◽

Classical Models ◽

Set Up ◽

Plume Flow ◽

Temperature Time ◽

Classical Shape

Abstract. We report the results of heating experiments carried out in an abandoned limestone quarry close to Paris, in an isolated room of a volume of about 400 m3. A heat source made of a metallic resistor of power 100 W was installed on the floor of the room, at distance from the walls. High-quality temperature sensors, with a response time of 20 s, were fixed on a 2 m long bar. In a series of 24 h heating experiments the bar had been set up horizontally at different heights or vertically along the axis of the plume to record changes in temperature distribution with a sampling time varying from 20 to 120 s. When taken in averages over 24 h, the temperatures present the classical shape of steady-state plumes, as described by classical models. On the contrary, the temperature time series show a rich dynamic plume flow with intermittent trains of oscillations, spatially coherent, of large amplitude and a period around 400 s, separated by intervals of relative quiescence whose duration can reach several hours. To our knowledge, no specific theory is available to explain this behavior, which appears to be a chaotic interaction between a turbulent plume and a stratified environment. The observed behavior, with first-order factorization of a smooth spatial function with a global temporal intermittent function, could be a universal feature of some turbulent plumes in geophysical environments.

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First-Order Frequency Effects in Supersonic Panel Flutter of Finite Cylindrical Shells

Journal of Applied Mechanics ◽

10.1115/1.3423007 ◽

1973 ◽

Vol 40 (2) ◽

pp. 464-470

Author(s):

M. Holt ◽

T. M. Lee

Keyword(s):

Mach Number ◽

Elastic Shell ◽

Order Effect ◽

Aerodynamic Load ◽

Panel Flutter ◽

Thin Cylindrical Shell ◽

First Order ◽

Flutter Boundary ◽

Shell Equation ◽

Set Up

An improved calculation of the supersonic panel flutter characteristics of a thin cylindrical shell of finite length is presented. The aerodynamic load is determined with account taken of first-order terms in vibration frequency, and when this is introduced into the elastic shell equation an integro differential equation results. An equivalent eigenvalue problem is set up by applying Galerkin’s method to this equation. The flutter boundary, for given Mach number and circumferential mode n, corresponds to the shell thickness ratio at which the real part of any one of the eigenvalues first becomes non-negative. It is found that the most severe flutter condition, for given Mach number, occurs for a circumferential mode n = 7. The present calculations exclude second-order frequency terms in the elastic part of the flutter equation, even though they may have a first-order effect. A subsequent calculation referred to here shows that these terms indeed have no significant influence on the first-order analysis.

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Surface energies emerging in a microscopic, two-dimensional two-well problem

Proceedings of the Royal Society of Edinburgh Section A Mathematics ◽

10.1017/s0308210516000433 ◽

2017 ◽

Vol 147 (5) ◽

pp. 1041-1089 ◽

Cited By ~ 3

Author(s):

Georgy Kitavtsev ◽

Stephan Luckhaus ◽

Angkana Rüland

Keyword(s):

Surface Energy ◽

Two Dimensional ◽

Direct Control ◽

First Order ◽

Surface Energies ◽

Energy Scaling ◽

Continuous Analogue ◽

Dimensional Shape ◽

Set Up ◽

Microscopic Modelling

In this paper we are interested in the microscopic modelling of a two-dimensional two-well problem that arises from the square-to-rectangular transformation in (two-dimensional) shape-memory materials. In this discrete set-up, we focus on the surface energy scaling regime and further analyse the Hamiltonian that was introduced by Kitavtsev et al. in 2015. It turns out that this class of Hamiltonians allows for a direct control of the discrete second-order gradients and for a one-sided comparison with a two-dimensional spin system. Using this and relying on the ideas of Conti and Schweizer, which were developed for a continuous analogue of the model under consideration, we derive a (first-order) continuum limit. This shows the emergence of surface energy in the form of a sharp-interface limiting model as well the explicit structure of the minimizers to the latter.

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Research of technical characteristics of wall leveling signs in the context of the ethymology of terms

Modern achievements of geodesic science and industry ◽

10.33841/1819-1339-1-41-55-60 ◽

2021 ◽

Vol 41 (I) ◽

pp. 55-60

Author(s):

I. TREVOHO ◽

◽

A. DRBAL ◽

E. ILKIV ◽

M. GALYARNYK ◽

...

Keyword(s):

Geodetic Network ◽

The Black Sea ◽

Historical Sources ◽

Term Operation ◽

Geodetic Networks ◽

City Environment ◽

Technical Developments ◽

The City ◽

Technical Recommendations

The aim is to clarify the etymology of the terms “wall leveling mark” and “wall leveling benchmark” in the context of the historical sequence of the appearance of leveling networks in the Ukrainian lands to present the author’s view on these definitions in scientific reference and encyclopedic geodetic literature. To conduct a chronological study of the phenomenon of leveling wall signs of different structures and the corresponding technologies of binding to them in leveling networks, which were created in the Ukrainian lands during the XIX–XXI centuries. Pay attention to the fact that level marks and wall frames, which are valid (working) independent geodetic signs in leveling networks, due to long-term operation are carriers of important geodetic information. Method. To study the results of the analysis of historical sources, standards, reference, encyclopedic and scientific literature in the context of the analysis of the definitions of “level mark” and “wall benchmark” was used analysis of patterns of functioning of the relevant geodetic terminological units. Results. On the territory of Ukraine during the XIX–XXI centuries. Created a leveling (height) network [State Geodetic Network, experimental operation], which operates to this day. The functioning of the leveling (height) network is regulated by legislative acts and regulations. Thanks to the geo-portal of the DGM of Ukraine created by NDIGK, it is possible to obtain information about the preserved level signs. The peculiarity of the leveling (height) network is that it was created by different departments of different countries [Glushkov V.V., 2003] with different height systems and taking into account the access of Ukrainian lands to the Black Sea. All this led to the use of different designs of wall leveling signs and, accordingly, their interpretation, which is not sufficiently reflected in the geodetic reference and regulatory literature. Scientific novelty. The performed comprehensive analysis of information sources can serve as a basis for development of scientific and technical recommendations formonitoring of level signs ofDGMofUkraine and will allow to reveal weaknesses of their functioning which are caused by changes in vital activity of the city environment. The practical value of the work is to solve the problem of distinguishing the production characteristics of the wall leveling mark and wall leveling benchmark, which are fixed leveling signs in geodetic networks of thickening and leveling networks to develop technical developments for inspection and updating points II, leveling networks classes and geodetic networks of thickening in the context of monitoring of geodetic points of DGM of Ukraine and their corresponding representation in the scientific and reference geodetic literature.

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Prospects of Metrological Provision Linear Geodetic of Measurements on the Geodetic Test Field

Reports on Geodesy and Goeinformatics ◽

10.2478/rgg-2013-0007 ◽

2013 ◽

Vol 94 (1) ◽

pp. 56-63

Author(s):

Trevoho I.S. ◽

Tsyupak I.M.

Keyword(s):

Metrological Support ◽

Metrological Provision ◽

Geodetic Network ◽

Test Field ◽

Gnss Receivers ◽

Standard Linear ◽

Working Standards

Abstract This paper gives brief information on existing metrological support for the Yavoriv of scientific of the geodetic of test field (SGTF) for testing of modern of surveying equipment (rangefinders, electronic total stations and GNSS receivers). Analyzed ways to improve the fundamental geodetic network and the standard linear of basis, as working standards for testing, in accordance, GNSS receivers and a rangefinders, as well as for study an accuracy technology of GNSS leveling.

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From storytelling to Facebook. Content biases when retelling or sharing a story

10.31219/osf.io/br56y ◽

2021 ◽

Author(s):

Alberto Acerbi

Keyword(s):

Social Network ◽

Cultural Evolution ◽

Cultural Transmission ◽

Specific Content ◽

Oral Storytelling ◽

Oral Transmission ◽

Related Information ◽

Transmission Chain ◽

Set Up ◽

Content Information

Cultural evolution researchers use transmission chain experiments to investigate which content is more likely to survive when transmitted from one individual to another. These experiments resemble oral storytelling, where individuals need to understand, memorise, and reproduce the content. However, prominent contemporary forms of cultural transmission—think an online sharing— only involve the willingness to transmit the content. Here I present two fully preregistered online experiments that explicitly investigated the differences between these two modalities of transmission. The first experiment (N=1080) examined whether negative content, information eliciting disgust, and threat-related information were better transmitted than their neutral counterpart in a traditional transmission chain set-up. The second experiment (N=1200), used the same material, but participants were asked whether they would share or not the content in two conditions: in a large anonymous social network, or with their friends, in their favourite social network. Negative content was both better transmitted in transmission chain experiments and shared more than its neutral counterpart. Threat-related information was successful in transmission chain experiments but not when sharing, and, finally, information eliciting disgust was not advantaged in either. Overall, the results present a composite picture, suggesting that the interactions between the specific content and the medium of transmission are important and, possibly, that content biases are stronger when memorisation and reproduction are involved in the transmission—like in oral transmission—than when they are not—like in online sharing.

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Corner Reflector Network as a Geodetic Reference for Landslide Monitoring via InSAR Time Series: Case Study from Slovakia

10.5194/egusphere-egu21-12373 ◽

2021 ◽

Author(s):

Richard Czikhardt ◽

Juraj Papco ◽

Peter Ondrejka ◽

Peter Ondrus ◽

Pavel Liscak

Keyword(s):

Time Series ◽

Horizontal Displacement ◽

Terrestrial Reference Frame ◽

Sar Interferometry ◽

Global Navigation Satellite Systems ◽

Reference Network ◽

Landslide Monitoring ◽

First Order ◽

Order Estimation ◽

Better Than

SAR interferometry (InSAR) is inherently a relative geodetic technique requiring one temporal and one spatial reference to obtain the datum-free estimates on millimetre-level displacements within the network of radar scatterers. To correct the systematic errors, such as the varying atmospheric delay, and solve the phase ambiguities, it relies on the first-order estimation network of coherent point scatterers (PS).For vegetated and sparsely urbanized areas, commonly affected by landslides in Slovakia, it is often difficult to construct a reliable first-order estimation network, as they lack the PS. Purposedly deploying corner reflectors (CR) at such areas strengthens the estimation network and, if these CR are collocated with a Global Navigation Satellite Systems (GNSS), they provide an absolute geodetic reference to a well-defined terrestrial reference frame (TRF), as well as independent quality control.For landslides, line-of-sight (LOS) InSAR displacements can be difficult to interpret. Using double CR, i.e. two reflectors for ascending/descending geometries within a single instrument, enables the assumption-less decomposition of the observed cross-track LOS displacements into the vertical and the horizontal displacement components.In this study, we perform InSAR analysis on the one-year of Sentinel-1 time series of five areas in Slovakia, affected by landslides. 24 double back-flipped trihedral CR were carefully deployed at these sites to form a reference network, guaranteeing reliable displacement information over the critical landslide zones. To confirm the measurement quality, we show that the temporal average Signal-to-Clutter Ratio (SCR) of the CR is better than 20 dB. The observed CR motions in vertical and east-west directions vary from several millimetres up to 3 centimetres, with average standard deviation better than 0.5 mm. Repeated GNSS measurements of the CR confirm the displacement observed by the InSAR, improve the positioning precision of the nearby PS, and attain the transformation into the national TRF.

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