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Number of results: 11
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Abstract

Terrestrial laser scanner (TLS) is a new class of survey instruments to capture spatial data developed rapidly. A perfect facility in the oil industry does not exist. As facilities age, oil and gas companies often need to revamp their plants to make sure the facilities still meet their specifications. Due to the complexity of an oil plant site, there are difficulties in revamping, having all dimensions and geometric properties, getting through narrow spaces between pipes and having the description label of each object within a facility site. So it is needed to develop an accurate observations technique to overcome these difficulties. TLS could be an unconventional solution as it accurately measures the coordinates identifying the position of each object within the oil plant and provide highly detailed 3D models. This paper investigates creating 3D model for Ras Gharib oil plant in Egypt and determining the geometric properties of oil plant equipment (tank, vessels, pipes . . . etc.) using TLS observations and modeling by CADWORX program. The modeling involves an analysis of several scans of the oil plant. All the processes to convert the observed points cloud into a 3D model are described. The geometric properties for tanks, vessels and pipes (radius, center coordinates, height and consequently oil volume) are also calculated and presented. The results provide a significant improvement in observing and modeling of an oil plant and prove that the TLS is the most effective choice for generating a representative 3D model required for oil plant revamping.

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Authors and Affiliations

Ahlam I. Elgndy
Zaki M. Zeidan
Ashraf A. Beshr
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Abstract

Land surveyors, photogrammetrists, remote sensing engineers and professionals in the Earth sciences are often faced with the task of transferring coordinates from one geodetic datum into another to serve their desired purpose. The essence is to create compatibility between data related to different geodetic reference frames for geospatial applications. Strictly speaking, conventional techniques of conformal, affine and projective transformation models are mostly used to accomplish such task. With developing countries like Ghana where there is no immediate plans to establish geocentric datum and still rely on the astro-geodetic datums as it national mapping reference surface, there is the urgent need to explore the suitability of other transformation methods. In this study, an effort has been made to explore the proficiency of the Extreme Learning Machine (ELM) as a novel alternative coordinate transformation method. The proposed ELM approach was applied to data found in the Ghana geodetic reference network. The ELM transformation result has been analysed and compared with benchmark methods of backpropagation neural network (BPNN), radial basis function neural network (RBFNN), two-dimensional (2D) affine and 2D conformal. The overall study results indicate that the ELM can produce comparable transformation results to the widely used BPNN and RBFNN, but better than the 2D affine and 2D conformal. The results produced by ELM has demonstrated it as a promising tool for coordinate transformation in Ghana.

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Authors and Affiliations

Yao Yevenyo Ziggah
Yakubu Issaka
Prosper Basommi Laari
Zhenyang Hui
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Abstract

In this paper, two techniques for calculating the geoid-to-quasigeoid separation are employed. One of them is GPS/Levelling customary method as a criterion where the geoid undulation and height anomaly are computed by subtracting the ellipsoid height attained via GPS from the orthometric height and normal height, respectively. Another approach is Sjöberg’s equation. We have used of the ICGEM website for definition of the variables of the Sjöberg’s equation, as the applied reference model is the EGM2008 global geopotential model and WGS84 reference ellipsoid. The investigations are performed over the stations of the GPS/Leveling network related to three selected areas in desert, mountain and flatland namely the Lout, Zagros and Khuzestan in Iran and afterward the correlation coefficient between the geoid-to-quasigeoid separation calculated using the satellite data in Sjöberg’s equation and GPS/Levelling method is estimated. The results indicate a straight correlation between the estimated separations from the two methods as its value for the Lout is 0.754, for the Zagros is 0.497 and for the Khuzestan is 0.659. consequently, using the satellite data in Sjöberg’s equation for the regions where there are not the GPS/Levelling and land gravity data, specially for the even areas, yield a satisfactory response of the geoidto-quasigeoid separation.

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Authors and Affiliations

Ata Eshaghzadeh
Roghayeh Alsadat Kalantari
Zohreh Moeini Hekmat
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Abstract

The issue of line simplification is one of the fundamental problems of generalisation of geographical information, and the proper parameterisation of simplification algorithms is essential for the correctness and cartographic quality of the results. The authors of this study have attempted to apply computational intelligence methods in order to create a cartographic knowledge base that would allow for non-standard parameterisation of WEA (Weighted Effective Area) simplification algorithm. The aim of the conducted research was to obtain two independent methods of non-linear weighting of multi-dimensional regression function that determines the “importance” of specific points on the line and their comparison to each other. The first proposed approach consisted in the preparation of a set of cartographically correct examples constituting a basis for teaching a neural network, while the other one consisted in defining inference rules using fuzzy logic. The obtained results demonstrate that both methods have great potential, although the proposed solutions require detailed parameterisation taking into account the specificity of geometric variety of the source data.

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Authors and Affiliations

Robert Olszewski
Miłosz Gnat
Anna Fiedukowicz
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Abstract

The graphical user interface (GUI) and the functionality of various global map services in the context of responsive web design were compared in the article. The analysis included: the number and arrangement of buttons on the start screen, available map layers, waypoints and means of transport for searched routes on four screens of various sizes: the desktop computer, laptop, tablet, and smartphone screen. Having compared the interface and the functionality of eight global map services (Baidu Maps, Google Maps, HereWeGo, Bing Maps, Open Street Map, Map Quest, 2Gis, Yandex Maps), authors draw conclusions concerning responsive web design. Despite the fact that specific map services differ, there are some common features making a good example of the adaptation of the graphical user interface to the device on which the map is presented. Global map services, regardless of the display size, use the same interactive tools that are graphically similar. Among those graphic similarities, one can distinguish two or three graphical styles representing a single function. Two versions of the interface can be observed – the desktop and mobile type. Adaptation to devices such as laptops or tablets assumes that only the screen decreases but the interface and the functionality remains relatively unchanged. Real responsiveness occurs only when service is displayed on a smartphone display.

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Authors and Affiliations

Tymoteusz Horbiński
Paweł Cybulski
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Abstract

In this publication, the strategy of land resources administration is presented on the basis of consideration of proposed result factors. The research methodology is based on the use of the PESTLE analytical model in conjunction with economic-mathematical modeling. The scientific novelty of the publication is developing the technology of administration of land resources on the basis of cadastral and other statistical information, which allows obtaining scientifically grounded solutions on the use of land resources. Considering the process of Land Resources Administration as a procedure based on making certain decisions when creating a management system which takes into account the internal and external relationships in this system, the postulate is about determining the degree of trust in this system, establishing economic, environmental and social risks when using it. To a certain extent, the process of Land Resources Administration is a prediction of the effective use of this natural potential in the future. It should be noted that the reliability of the forecast decision depends on the nature and parameters of uncertainties and the duration of their validity. Consequently, while making operational decisions on land resources for a short perspective, the forecasting is more reliable than for a long one. It becomes an effective mechanism of objective evaluation of the state of land resources and the prospects for their use. In this publication the main influencing decision making factors and the technological scheme of the solution of the problem are given.

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Authors and Affiliations

Lev Perovych
Ihor Perovych
Lesia Perovych
Oksana Ludchak
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Abstract

The paper presents a method of construction of cylindrical and azimuthal equalarea map projections of a triaxial ellipsoid. Equations of a triaxial ellipsoid are a function of reduced coordinates and functions of projections are expressed with use of the normal elliptic integral of the second kind and Jacobian elliptic functions. This solution allows us to use standard methods of solving such integrals and functions. The article also presents functions for the calculation of distortion. The maps illustrate the basic properties of developed map projections. Distortion of areas and lengths are presented on isograms and by Tissot’s indicatrixes with garticules of reduced coordinates. In this paper the author continues his considerations of the application of reduced coordinates to the construction of map projections for equidistant map projections. The developed method can be used in planetary cartography for mapping irregular objects, for which tri-axial ellipsoids have been accepted as reference surfaces. It can also be used to calculate the surface areas of regions located on these objects. The calculations were carried out for a tri-axial ellipsoid with semi-axes a = 267:5 m, b = 147 m, c = 104:5 m accepted as a reference ellipsoid for the Itokawa asteroid.

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Authors and Affiliations

Paweł Pędzich
Keywords ALS nDSM LULC changes
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Abstract

The purpose of the study was an assessment of LiDAR point clouds for automating the mapping of land use and land cover changes, mainly land abandonment and the process of secondary forest succession. Detailed information about land cover was determined based on airborne laser scanning data. The presented study focuses on the analysis of the spatial range and structure of vegetation. The study area was located in Milicz district in the voivodeship of Lower Silesia – the central west part of Poland. The areas of interest were parcels where agricultural land had been abandoned and forest succession processes had progressed. Analysis of the spatial range of the secondary forest succession was carried out using a reclassified nDSM. Reclassification of the nDSM was done using > 1 m, > 2 m and > 3 m for the pixel values, representing the height of vegetation above the ground. Parameters such as height of vegetation, standard deviation of height and cover density were calculated, to show the process of the increase in forest succession on abandoned agricultural land. The results confirmed a discrepancy between the cadastral data and the actual use of the plots. In the study area, more than three times as much forested and wooded area was detected than had been recorded in official databases. Analyses based on airborne laser scanning point clouds indicated significant diversity in the vertical and horizontal structure of vegetation. The results demonstrated gradual succession of greenery in the research area.

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Authors and Affiliations

Marta Szostak
Adrian Bednarski
Piotr Wężyk
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Abstract

Many different characteristics affect the land prices. This work attempts to analyse the characteristics of agricultural parcels, which significantly affect the variability of agricultural land prices. The article presents the methodology of selection land parcel characteristics, rules for the selection of factors and possibility of automatic acquisition of data in mass valuation process. The research aims at selecting determinants of agricultural land parcels price and evaluate theirs significance in a local market for the purpose of land values map elaboration. Using advanced statistical analysis of a non-linear influence of a parcel inherent characteristics on its price we proved that in the relatively small area, like commune, only a few characteristics are essential, They are: parcel size, shape and location expressed by distance to the commune centre, paved roads and homestead buildings. Therefore, these ones should be used for elaboration of land values map. Soil quality and a cropland type although significant for the land prices do not diversify land prices in local market. The novelty of the research relays on determination of non-linear influence of parcel characteristics on variation of agricultural land values based on the correlation ratio (h eta). The research was conducted for the undeveloped agricultural lands located in south-west Poland, the rural municipality Krotoszyce.

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Authors and Affiliations

Monika Maleta
Albina Mościcka
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Abstract

This paper provides analyses of the accuracy and convergence time of the PPP method using GPS systems and different IGS products. The official IGS products: Final, Rapid and Ultra Rapid as well as MGEX products calculated by the CODE analysis centres were used. In addition, calculations with weighting function of the observations were carried out, depending on the elevation angle. The best results were obtained for CODE products, with a 5-minute interval precision ephemeris and precise corrections to satellite clocks with a 30-second interval. For these calculations the accuracy of position determination was at the level of 3 cm with a convergence time of 44 min. Final and Rapid products, which were orbit with a 15-minute interval and clock with a 5 minute interval, gave very similar results. The same level of accuracy was obtained for calculations with CODE products, for which both precise ephemeris and precise corrections to satellite clocks with the interval of 5 minutes. For these calculations, the accuracy was 4 cm with the convergence time of 70 min. The worst accuracy was obtained for calculations with Ultra-rapid products, with an interval of 15 minutes. For these calculations, the accuracy was 10 cm with a convergence time of 120 min. The use of the weighting function improved the accuracy of position determination in each case, except for calculations with Ultra-rapid products. The use of this function slightly increased the convergence time, in addition to the CODE calculation, which was reduced to 9 min.

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Authors and Affiliations

Damian Kiliszek
Marcin Szołucha
Krzysztof Kroszczyński

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