scholarly journals Control Points Selection Based on Maximum External Reliability for Designing Geodetic Networks

2020 ◽  
Vol 10 (2) ◽  
pp. 687 ◽  
Author(s):  
Marcelo Tomio Matsuoka ◽  
Vinicius Francisco Rofatto ◽  
Ivandro Klein ◽  
Maurício Roberto Veronez ◽  
Luiz Gonzaga da Silveira ◽  
...  

A set of stable and identifiable points—known as control points—are interconnected by direction, distance or height differences measurements form a geodetic network. Geodetic networks are used in various branches of modern science, such as monitoring the man-made structures, analysing the crustal deformation of the Earth, establishing and maintaining a geospatial reference frame, mapping, civil engineering projects and others. One of the most crucial components for ensuring the network quality is Geodetic Network Design. The design of a geodetic network depends on its purpose. In this paper, an automatic procedure for selection of control points is proposed. The goal is to find the optimum control points location so that the maximum influence of an anomaly measurement (outlier) on the coordinates of the network is minimum. Here, the concept of Minimal Detectable Bias defines the size of the outlier and its propagation on the network coordinates is used to describe the external reliability. The proposed procedure was applied to design a levelling network. Two scenarios were investigated: design of a network with one control point (minimally constrained levelling network) and another with two control points (over-constrained levelling network). The centre of the network was the optimum position to set the control point. Results for that network reveal that the centre of the network was the optimum position to set the control point for the minimal constraint case, whereas the over-constraint case were those with less line connections. We highlight that the procedure is a generally applicable method.

Author(s):  
Marcelo Tomio Matsuoka ◽  
Vinicius Francisco Rofatto ◽  
Ivandro Klein ◽  
Mauricio Roberto Veronez ◽  
Luiz Gonzaga Da Silveira ◽  
...  

Geodetic networks are essential for most geodetic, geodynamics and civil projects, such as monitoring the position and deformation of man-made structures, monitoring the crustal deformation of the Earth, establishing and maintaining a geospatial reference frame, mapping, civil engineering projects and so on. Before the installation of geodetic marks and gathering of survey data, geodetic networks need to be designed according to the pre-established quality criteria. In this study, we present a method for designing geodetic networks based on the concept of reliability. We highlight that the method discards the use of the observation vector of Gauss-Markov model. In fact, the only needs are the geometrical network configuration and the uncertainties of the observations. The aim of the proposed method is to find the optimum configuration of the geodetic control points so that the maximum influence of an outlier on the coordinates of the network is minimum. Here, the concept of Minimal Detectable Bias defines the size of the outlier and its propagation on the parameters is used to describe the external reliability. The proposed method is demonstrated by practical application of one simulated levelling network. We highlight that the method can be applied not only for geodetic network problems, but also in any branch of modern science.


2020 ◽  
Vol 9 (3) ◽  
pp. 148
Author(s):  
Elzbieta Bielecka ◽  
Krzysztof Pokonieczny ◽  
Sylwia Borkowska

Geodetic networks provide a spatial reference framework for the positioning of any geographical feature in a common and consistent way. An even spatial distribution of geodetic control points assures good quality for subordinate surveys in mapping, cadaster, engineering activities, and many other land administration-oriented applications. We investigate the spatial pattern of geodetic control points based on GIScience theory, especially Tobler’s Laws in Geography. The study makes contributions in both the research and application fields. By utilizing Average Nearest Neighbor, multi-distance spatial cluster analysis, and cluster and outlier analysis, it introduces the comprehensive methodology for ex post analysis of geodetic control points’ spatial patterns as well as the quantification of geodetic networks’ uniformity to regularly dense and regularly thinned. Moreover, it serves as a methodological resource and reference for the Head Office of Geodesy and Cartography, not only the maintenance, but also the further densification or modernization the geodetic network in Poland. Furthermore, the results give surveyors the ability to quickly assess the availability of geodetic points, as well as identify environmental obstacles that may hamper measurements. The results show that the base geodetic control points are evenly dispersed (one point over 50 sq. km), however they tend to cluster slightly in urbanized areas and forests (1.3 and 1.4 points per sq. km, respectively).


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Ahmed A. G. AbdAllah ◽  
Zhengtao Wang

AbstractGeodetic networks are important for most engineering projects. Generally, a geodetic network is designed according to precision, reliability, and cost criteria. This paper provides a new criterion considering the distances between the Net Points (NPs) and the Project Border (PB) in terms of Neighboring (N). Optimization based on the N criterion seeks to relocate the NPs as close as possible to PB, which leads to creating shorter distances between NPs or those distances linking NPs with Target Points (TPs) to be measured inside PB. These short distances can improve the precision of NPs and increase the accuracy of observations and transportation costs between NPs themselves or between NPs and TPs (in real applications). Three normalized N objective functions based on L1, L2, and L∞‒norms were formulated to build the corresponding N optimization models, NL1; NL2; and NL∞ and to determine the best solution. Each model is subjected to safety, precision, reliability, and cost constraints. The feasibility of the N criterion is demonstrated by a simulated example. The results showed the ability of NL∞ to determine the safest positions for the NPs near PB. These new positions led to improving the precision of the network and preserving the initial reliability and observations cost, due to contradiction problems. Also, N results created by all N models demonstrate their theoretical feasibility in improving the accuracy of the observations and transportation cost between points. It is recommended to use multi-objective optimization models to overcome the contradiction problem and consider the real application to generalize the benefits of N models in designing the networks.


A national geodetic network provides the fundamental framework that enables attainment of high accuracy geodetic measurements. It plays a key role in the efficiency and reliability of operations in land surveying, mapping, remote sensing, Geographic Information System, engineering surveying and other related applications. The geodetic framework provides the basis for integrating all mapping and survey activities. About eighty per cent of the primary geodetic control points in Kenya, established in the early twentieth century, have been destroyed. This has resulted in expensive and time consuming operations and processes for geospatial professionals and scientists. This situation is particularly worse in central Kenya, hence the need to extend the geodetic control by establishing more control points on secure and accessible sites for use by geospatial professionals and scientists in a wide variety of applications. In this study, modern satellite positioning techniques were utilised to extend geodetic reference network in central Kenya. Existing geodetic control points were used to facilitate establishment of new geodetic control points distributed within the region. Field observations were carried out using Global Positioning System. The raw data were downloaded, edited, processed and adjusted using Leica Geo-Office software. The resulting final adjusted coordinates had a maximum standard deviation of 2cm and 5cm on horizontal and vertical coordinates respectively, and a general loop misclosure of less than one part per million. The results showed that the quality of established control point positions was high, and demonstrated the efficient extension of geodetic control network using modern satellite positioning systems and efficient computational techniques in situations such as the ones currently prevailing in central Kenya.


1996 ◽  
Vol 59 (11) ◽  
pp. 1242-1247 ◽  
Author(s):  
FRANK L. BRYAN

Decision trees have been used as an aid to selection of critical control points as part of the development of hazard analysis critical control point (HACCP) systems. The background for those in existence is described. Another decision-tree approach that follows the logic in the IAMFES manual Procedures to Implement the Hazard Analysis Critical Control Point Approach is presented. It takes into consideration impending hazards, the effect of actions exercised at the operation in question, whether control actions should be taken at this or subsequent operations and whether the CCP will be monitored and corrections made. Further, guidelines are given for selecting an operation as a critical control point. A decision tree to aid in the evaluation of risks is presented, considering whether illness will result, the severity of the illness and the likely occurrence of this outcome, based upon epidemiologic or challenge study of related events. These decision trees provide additional tools to aid in the development of HACCP systems.


2020 ◽  
Vol 3 (152) ◽  
pp. 92-99
Author(s):  
S. M. Geiko ◽  
◽  
O. D. Lauta

The article provides a philosophical analysis of the tropological theory of the history of H. White. The researcher claims that history is a specific kind of literature, and the historical works is the connection of a certain set of research and narrative operations. The first type of operation answers the question of why the event happened this way and not the other. The second operation is the social description, the narrative of events, the intellectual act of organizing the actual material. According to H. White, this is where the set of ideas and preferences of the researcher begin to work, mainly of a literary and historical nature. Explanations are the main mechanism that becomes the common thread of the narrative. The are implemented through using plot (romantic, satire, comic and tragic) and trope systems – the main stylistic forms of text organization (metaphor, metonymy, synecdoche, irony). The latter decisively influenced for result of the work historians. Historiographical style follows the tropological model, the selection of which is determined by the historian’s individual language practice. When the choice is made, the imagination is ready to create a narrative. Therefore, the historical understanding, according to H. White, can only be tropological. H. White proposes a new methodology for historical research. During the discourse, adequate speech is created to analyze historical phenomena, which the philosopher defines as prefigurative tropological movement. This is how history is revealed through the art of anthropology. Thus, H. White’s tropical history theory offers modern science f meaningful and metatheoretically significant. The structure of concepts on which the classification of historiographical styles can be based and the predictive function of philosophy regarding historical knowledge can be refined.


2021 ◽  
Vol 41 (I) ◽  
pp. 55-60
Author(s):  
I. TREVOHO ◽  
◽  
A. DRBAL ◽  
E. ILKIV ◽  
M. GALYARNYK ◽  
...  

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.


Author(s):  
Dan Obreja

The estimation of the hydrodynamics characteristics of the small ships rudders is an important issue in the initial design process. The manoeuvring performance depends on the type and geometry of the rudder. The control forces and moments generated by the rudder deflection can be calculated on the basis of the hydrodynamics characteristics of the rudder. A short description of the Mordvinov theoretical model is presented in this paper, in order to determine the hydrodynamics characteristics of a small ship rudder, with the propeller and hull influences. On the basis of the control forces and moments, the optimum position of the rudder stock and the selection of the steering gear can be performed. Using the Mordvinov method, the computer code PHP NM-MAN-HC was develop at the Research Centre of the Naval Architecture Faculty of “Dunarea de Jos” University of Galati. This computer code is integrated in the software platform PHP (Preliminary Hydrodynamics Performance) and is used for didactic applications and practical research activities in the small ship design process


2020 ◽  
Vol 206 ◽  
pp. 03025
Author(s):  
Junze Wang ◽  
Maohua Yao ◽  
Wenting Zhou ◽  
Xiangping Chen

In this paper, 24 C-level control points under different terrain conditions were selected to be the testing points. The binary-satellite system (GPS+GLONASS) and the triple-satellite system with BeiDou Navigation Satellite System (BDS) (BDS+GPS+GLONASS) were adopted for static measurement; and the observation data from BeiDou Ground-based Augumentation System (GBAS) base stations in Guangxi were collected for solution. By comparing the residuals of GPS tri-dimensional baseline vectors and the internal accord accuracy of each control point under the binary and triple-satellite systems, the effect of data collected by different satellite systems under different terrain conditions on measurement accuracy was studied. According to the results, (1) the triple-satellite system with BDS showed more stable measurement accuracy; (2) in plane, the two systems were of equivalent measurement accuracy in mountainous and flat areas; in elevation, the triple-satellite system showed higher and more stable measurement accuracy.


Author(s):  
Володимир Моркун ◽  
Сергій Семеріков ◽  
Наталія Моркун ◽  
Світлана Грищенко ◽  
Арнольд Ків

Morkun S.V., Semerikov S.O., Morkun N.V., Hryshchenko S.M. and Kiv A.E. Defining the Structure of Environmental Competence of Future Mining Engineers: ICT Approach. The object is to the reasonable selection of the ICT tools for formation of ecological competence. Pressing task is constructive and research approach to preparation of future engineers to performance of professional duties in order to make them capable to develop engineering projects independently and exercise control competently. Subject of research: the theoretical justification of competence system of future mining engineers. Methods: source analysis on the problem of ecological competence formation. Results: defining the structure of environmental competence of future mining engineers. Conclusion: the relevance of the material covered in the article, due to the need to ensure the effectiveness of the educational process in the preparation of the future mining engineers.


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