This document describes the production of a geoidal map and three-dimensional surface model for part of Port Harcourt, Nigeria using "Satlevel" collocation modeling. Global Navigation Satellite System data was collected to determine ellipsoidal heights, while leveling provided orthometric heights. These were used in the "Satlevel" collocation model to compute geoidal undulations, which were contoured in Surfer software to generate the geoidal map and 3D surface model. The map depicts the geoid configuration of the study area and can be used with ellipsoidal heights from GNSS to determine orthometric heights, providing a simpler method than conventional techniques.
Titan’s Topography and Shape at the Endof the Cassini MissionSérgio Sacani
With the conclusion of the Cassini mission, we present an updated topographic map of Titan,including all the available altimetry, SARtopo, and stereophotogrammetry topographic data sets availablefrom the mission. We use radial basis func tions to interpolate the sparse data set, which covers only ∼9%of Titan’s global area. The most notable updates to the topography include higher coverage of the polesof Titan, improved fits to the global shape, and a finer resolution of the global interpolation. We alsopresent a statistical analysis of the error in the derived products and perform a global minimization on aprofile-by-profile basis to account for observed biases in the input data set. We find a greater flattening ofTitan than measured, additional topographic rises in Titan’s southern hemisphere and better constrain thepossible locations of past and present liquids on Titan’s surface.
Accuracy enhancement of srtm and aster dems using weight estimation regressio...eSAT Publishing House
This document assesses the accuracy of SRTM and ASTER DEMs in Egypt by comparing DEM elevations to GPS ground control points (GCPs) in two study areas with different topography: a flat delta region and a hilly desert region. Root mean square errors (RMSEs) for SRTM ranged from 15.6m in the delta to 7.9m in the desert, and for ASTER ranged from 13.2m in the delta to 12.4m in the desert. A new approach using weight estimation regression models with topographic indices and aspects as predictors improved accuracy, reducing standard errors of estimates.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Urban Land Cover Change Detection Analysis and Modelling Spatio-Temporal Grow...Bayes Ahmed
This is my final Mater thesis presentation. The thesis defense was held on March' 07, 2011 at 15:30 in the seminar room of Universitat Jaume I (UJI), Castellón, Spain.
This document discusses using remote sensing and GIS for wetland mapping. It first provides background on wetlands and their functions. It then discusses how remote sensing, beginning with Landsat in 1972, has been used to map and monitor wetlands over time. The document reviews common remote sensing and image processing methods used in wetland mapping and summarizes two case studies on mapping wetland change in Iran and India using multi-temporal satellite data and GIS analysis.
This document summarizes three case studies that used remote sensing and GIS techniques to analyze land use and land cover change over time. The first case study analyzed changes from 1990-2010 in Hawalbagh, India using Landsat imagery. It found increases in built-up land and decreases in barren land. The second studied coastal Egypt from 1987-2001 using Landsat, identifying 8 land cover classes. The third examined Simly watershed, Pakistan from 1992-2012 using Landsat and SPOT data, finding increases in agriculture and decreases in vegetation. All three used supervised classification and post-classification comparison to analyze land use/cover changes.
This document provides an overview of photogrammetry, including a brief history of aerial photography, definitions of key terms, and descriptions of different types of photogrammetry and imaging. It discusses the general photogrammetric process and products that can be created. Specific topics covered include the development of aerial photography from the 1850s onwards, definitions of photogrammetry, close range, terrestrial, aerial, and space photogrammetry, types of aerial images, photogrammetric mapping techniques, and historical photogrammetric plotting instruments.
This document provides a training report on thematic mapping through remote sensing and GIS techniques in Siwani area, Bhiwani, Haryana, India. It acknowledges the support received from Haryana Space Applications Centre (HARSAC) in providing facilities and guidance for the summer training project. The project aimed to prepare base maps, land use/land cover maps, and geomorphology maps of the study area. It also aimed to familiarize the author with GIS techniques for map preparation and with using global positioning systems. The report includes chapters on the study area description, data and methodology used, and results and discussion of the project.
Titan’s Topography and Shape at the Endof the Cassini MissionSérgio Sacani
With the conclusion of the Cassini mission, we present an updated topographic map of Titan,including all the available altimetry, SARtopo, and stereophotogrammetry topographic data sets availablefrom the mission. We use radial basis func tions to interpolate the sparse data set, which covers only ∼9%of Titan’s global area. The most notable updates to the topography include higher coverage of the polesof Titan, improved fits to the global shape, and a finer resolution of the global interpolation. We alsopresent a statistical analysis of the error in the derived products and perform a global minimization on aprofile-by-profile basis to account for observed biases in the input data set. We find a greater flattening ofTitan than measured, additional topographic rises in Titan’s southern hemisphere and better constrain thepossible locations of past and present liquids on Titan’s surface.
Accuracy enhancement of srtm and aster dems using weight estimation regressio...eSAT Publishing House
This document assesses the accuracy of SRTM and ASTER DEMs in Egypt by comparing DEM elevations to GPS ground control points (GCPs) in two study areas with different topography: a flat delta region and a hilly desert region. Root mean square errors (RMSEs) for SRTM ranged from 15.6m in the delta to 7.9m in the desert, and for ASTER ranged from 13.2m in the delta to 12.4m in the desert. A new approach using weight estimation regression models with topographic indices and aspects as predictors improved accuracy, reducing standard errors of estimates.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Urban Land Cover Change Detection Analysis and Modelling Spatio-Temporal Grow...Bayes Ahmed
This is my final Mater thesis presentation. The thesis defense was held on March' 07, 2011 at 15:30 in the seminar room of Universitat Jaume I (UJI), Castellón, Spain.
This document discusses using remote sensing and GIS for wetland mapping. It first provides background on wetlands and their functions. It then discusses how remote sensing, beginning with Landsat in 1972, has been used to map and monitor wetlands over time. The document reviews common remote sensing and image processing methods used in wetland mapping and summarizes two case studies on mapping wetland change in Iran and India using multi-temporal satellite data and GIS analysis.
This document summarizes three case studies that used remote sensing and GIS techniques to analyze land use and land cover change over time. The first case study analyzed changes from 1990-2010 in Hawalbagh, India using Landsat imagery. It found increases in built-up land and decreases in barren land. The second studied coastal Egypt from 1987-2001 using Landsat, identifying 8 land cover classes. The third examined Simly watershed, Pakistan from 1992-2012 using Landsat and SPOT data, finding increases in agriculture and decreases in vegetation. All three used supervised classification and post-classification comparison to analyze land use/cover changes.
This document provides an overview of photogrammetry, including a brief history of aerial photography, definitions of key terms, and descriptions of different types of photogrammetry and imaging. It discusses the general photogrammetric process and products that can be created. Specific topics covered include the development of aerial photography from the 1850s onwards, definitions of photogrammetry, close range, terrestrial, aerial, and space photogrammetry, types of aerial images, photogrammetric mapping techniques, and historical photogrammetric plotting instruments.
This document provides a training report on thematic mapping through remote sensing and GIS techniques in Siwani area, Bhiwani, Haryana, India. It acknowledges the support received from Haryana Space Applications Centre (HARSAC) in providing facilities and guidance for the summer training project. The project aimed to prepare base maps, land use/land cover maps, and geomorphology maps of the study area. It also aimed to familiarize the author with GIS techniques for map preparation and with using global positioning systems. The report includes chapters on the study area description, data and methodology used, and results and discussion of the project.
Land Cover maps supply information about the physical material at the surface of the Earth (i.e. grass, trees, bare ground, asphalt, water, etc.). Usually they are 2D representations so to present variability of land covers about latitude and longitude or other type of earth coordinates. Possibility to link this variability to the terrain elevation is very useful because it permits to investigate probable correlations between the type of physical material at the surface and the relief. This paper is aimed to describe the approach to be followed to obtain 3D visualizations of land cover maps in GIS (Geographic Information System) environment. Particularly Corine Land Cover vector files concerning Campania Region (Italy) are considered: transformed raster files are overlapped to DEM (Digital Elevation Model) with adequate resolution and 3D visualizations of them are obtained using GIS tool. The resulting models are discussed in terms of their possible use to support scientific studies on Campania Land Cover.
Techniques of Land Surveying
The structure of Presentation:
Introduction to Land Survey
History of Land Survey
Types of Land Survey
Measurements
Modern Technologies
Geographical Information System
Photogrammetry
LiDAR
Airborne LiDAR
3D laser scanners
The document summarizes a project to create an accurate slope model for Jefferson County, West Virginia using Light Detection and Ranging (LiDAR) data. Field measurements of slope were taken at 34 locations and compared to slope models derived from 10-meter, 3-meter, and 1-meter digital elevation models. The 1-meter LiDAR data was found to most accurately represent the terrain with a higher R2 value and finer detail. The created slope model using this data could potentially be used for planning purposes when combined with other data layers.
Development of Methodology for Determining Earth Work Volume Using Combined S...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This document discusses geo-referencing and geo-coding. Geo-referencing is the process of aligning raster images and vector data to real-world coordinates so they can be overlaid and analyzed with other geographic data in a GIS. There are two main types: geo-referencing raster images and geo-referencing vector data. Geo-coding involves assigning coordinates to point data, often by matching addresses. While geo-referencing aligns geographic images, geo-coding specifically matches addresses to latitude and longitude coordinates.
Visualizing 3D atmospheric data with spherical volume texture on virtual globesJianming Liang
This document proposes a volumetric ray-casting framework to visualize atmospheric volume data on virtual globes. It allows for direct visualization of data in a spherical coordinate system without resampling, avoiding oversampling or undersampling issues. The framework also enables real-time vertical scaling of the data for better observation of altitudinal variations. The spherical volume ray-casting is implemented using deferred rendering to integrate volume effects with other geospatial data layers on a virtual globe.
This document outlines the syllabus for a course on Geographic Information Systems (GIS). The course is divided into 5 units that cover fundamentals of GIS, spatial data models, data input and topology, data analysis, and applications of GIS. The objectives are to introduce GIS fundamentals and processes of data management, analysis, and output. Students will learn about spatial data structures, data quality standards, and tools for data input, analysis, and management. The course aims to provide knowledge of GIS concepts and techniques.
The document discusses the application of remote sensing and geographical information systems (GIS) in civil engineering. It provides definitions of remote sensing as remotely sensing objects on Earth and GIS as a system to capture, store, analyze and present geographically referenced data. The document outlines some basic concepts of GIS including its origins from technologies like computer-aided cartography and databases. It also discusses data types in GIS like spatial data, attributes and different data models. Common software, functional elements and applications of GIS in areas like facilities management and environmental planning are summarized as well.
Topographic Information System as a Tool for Environmental Management, a Case...iosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online.
This document provides an introduction to Geographic Information Systems (GIS). It defines GIS as a system designed to store, manipulate, analyze and display spatially referenced data. The key components of a GIS are hardware, software and data. Common GIS software includes desktop programs like ArcGIS and open-source options like QGIS. GIS can incorporate different types of spatial data like raster, vector and remote sensing data along with associated attribute tables. Example applications discussed are in hydrology, including watershed analysis and flood modeling.
Comparison among Height Observation of GPS, Total Station and Level and their...IRJET Journal
This document compares the accuracy of GPS, total station, and level instruments for measuring elevation in mining works by using GIS technology. Statistical analysis showed the level measurements had the lowest variation while GPS had the highest. Topographic maps were created from observations from each instrument, showing they produced similar overall elevation patterns. The document concludes that while GPS and total station measurements have some error, their accuracy is sufficient for mining works. GIS allows easy analysis and use of elevation data from any of the three instruments.
A Solution to Land Area Calculation for Android Phone using GPS-Luwei YangLuwei Yang
This document proposes an Android application to calculate land area using GPS. It records a user's path using GPS as they walk around a land area. It then calculates the total land area using the trapezoid method, which breaks the irregular shape into smaller trapezoids. The Kalman filter is used to improve GPS accuracy and reduce errors, achieving an average error of 3.64% in tests. Key aspects include using Gauss-Kruger projection to convert GPS coordinates to plane coordinates before area calculation, and employing the trapezoid method and Kalman filtering to accurately calculate irregular land shapes and compensate for GPS errors, respectively.
The document discusses using GIS for a bridge inventory project for the City of New Haven, CT. Key project elements included collecting location and condition data for bridges during site visits, developing a database and summary reports, prioritizing bridges, and delivering the results in a digital map format to help the city manage its bridge infrastructure. The GIS approach integrated data on bridge locations, conditions and priorities to provide a comprehensive inventory and assessment tool.
The document discusses GPS satellites, receivers, and software. It provides the following key details:
- GPS satellites orbit the Earth at about 20,000 km and there are 24 satellites that complete two orbits per day. They are operated by the US Air Force.
- GPS receivers accurately calculate location by receiving signals from the satellites. Initially for military use, most receivers are now in cars and smartphones.
- GPS navigation software provides turn-by-turn directions based on maps or tracks a user's location and allows preprogrammed routes.
- GPS devices indicate location, routes, traffic, places of interest and provide turn-by-turn navigation via maps and text or speech. They track location for
Mapping the Wind Power Density and Weibull Parameters for Some Libyan Citiesinventionjournals
In order to introduce a well-informed decision regarding positioning of wind farm projects, prior intensive data collection, processing, and analysis are required. In this paper, wind data of twenty-five Libyan cities has been collected, processed, and analyzed to determine Weibull distribution parameters and the wind energy density for each of the twenty-five cities. The study is based on a recorded historical data from NASA of air temperature, barometric pressure, and wind speed for ten years along the period from January 1 st, 2005 to December 31st, 2014. The data used are the daily average values for each of the three parameters. Three methods have been used to estimate Weibull parameters namely: 1) the power density method, 2) the maximum likelihood method, and 3) the moment method. The goodness-of-fit for each method is, then, compared using the mean absolute error and the root mean square error methods. Lack of information regarding wind energy surveys for this particular region was one of the key factors in conducting such a comprehensive analysis.
This document discusses flood modelling and prediction in Kerala using GIS and remote sensing. It provides background on Kerala's geography and climate, which causes frequent flooding. It then describes how GIS and remote sensing tools like digital elevation models, land use data, and rainfall data can be used as inputs to model flood inundation areas and predict future flooding. The outputs of these models, like flood extent maps, can help with disaster management and planning flood prevention measures.
Photogrammetry Survey- Surveying II , Civil Engineering StudentsPramesh Hada
Photogrammetry is the science of making measurements from photographs. It involves planning and taking photographs, processing the photographs, and measuring the photographs to produce results like maps and 3D models.
There are two main types of photographs used in photogrammetry - terrestrial and aerial photographs. Terrestrial photographs are taken from ground-based camera stations using a phototheodolite. Aerial photographs are taken from an airborne camera mounted on an aircraft and can be vertical or oblique.
Key applications of photogrammetry include topographic mapping, engineering surveys, geological mapping, and urban and regional planning due to its ability to cover large areas quickly and accurately.
The document discusses the application of geographic information systems (GIS) in natural resource management (NRM). It provides examples of how GIS is used for hazard and risk management like mapping forest fires, tsunamis, and soil erosion. GIS aids in change detection, natural resource inventories, and environmental monitoring. Case studies demonstrate how GIS has been applied to assess risks from hazardous waste transport and identify high traffic road sections. In summary, the document outlines the various uses of GIS technology in studying, analyzing, and managing natural resources and environmental risks.
This document provides an overview of geographical information systems (GIS) and their concepts. It discusses that GIS allows for the integration of spatial and non-spatial data in a digital format to aid decision making. Key points include that GIS represents geographic features as vector or raster data, integrates data from different sources by georeferencing to a common coordinate system, and can perform spatial analysis and modeling to answer questions about patterns and relationships. GIS is a useful tool for tasks like natural resource management, precision agriculture, and land use planning.
To create a 4Vcard profile, visit 4vcard.com and register an account by filling in basic contact details and services offered. The profile can then be customized by uploading an avatar photo, selecting a username, and previewing the public profile. The completed 4Vcard URL can be shared to promote translation services everywhere.
O documento discute a produção da informação na era digital. Apresenta conceitos como sociedade em rede, economia da informação, propriedade intelectual e softwares livres versus proprietários. Destaca que a internet descentralizou a produção e distribuição da informação, tornando-a um bem não rival e de baixo custo.
Land Cover maps supply information about the physical material at the surface of the Earth (i.e. grass, trees, bare ground, asphalt, water, etc.). Usually they are 2D representations so to present variability of land covers about latitude and longitude or other type of earth coordinates. Possibility to link this variability to the terrain elevation is very useful because it permits to investigate probable correlations between the type of physical material at the surface and the relief. This paper is aimed to describe the approach to be followed to obtain 3D visualizations of land cover maps in GIS (Geographic Information System) environment. Particularly Corine Land Cover vector files concerning Campania Region (Italy) are considered: transformed raster files are overlapped to DEM (Digital Elevation Model) with adequate resolution and 3D visualizations of them are obtained using GIS tool. The resulting models are discussed in terms of their possible use to support scientific studies on Campania Land Cover.
Techniques of Land Surveying
The structure of Presentation:
Introduction to Land Survey
History of Land Survey
Types of Land Survey
Measurements
Modern Technologies
Geographical Information System
Photogrammetry
LiDAR
Airborne LiDAR
3D laser scanners
The document summarizes a project to create an accurate slope model for Jefferson County, West Virginia using Light Detection and Ranging (LiDAR) data. Field measurements of slope were taken at 34 locations and compared to slope models derived from 10-meter, 3-meter, and 1-meter digital elevation models. The 1-meter LiDAR data was found to most accurately represent the terrain with a higher R2 value and finer detail. The created slope model using this data could potentially be used for planning purposes when combined with other data layers.
Development of Methodology for Determining Earth Work Volume Using Combined S...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This document discusses geo-referencing and geo-coding. Geo-referencing is the process of aligning raster images and vector data to real-world coordinates so they can be overlaid and analyzed with other geographic data in a GIS. There are two main types: geo-referencing raster images and geo-referencing vector data. Geo-coding involves assigning coordinates to point data, often by matching addresses. While geo-referencing aligns geographic images, geo-coding specifically matches addresses to latitude and longitude coordinates.
Visualizing 3D atmospheric data with spherical volume texture on virtual globesJianming Liang
This document proposes a volumetric ray-casting framework to visualize atmospheric volume data on virtual globes. It allows for direct visualization of data in a spherical coordinate system without resampling, avoiding oversampling or undersampling issues. The framework also enables real-time vertical scaling of the data for better observation of altitudinal variations. The spherical volume ray-casting is implemented using deferred rendering to integrate volume effects with other geospatial data layers on a virtual globe.
This document outlines the syllabus for a course on Geographic Information Systems (GIS). The course is divided into 5 units that cover fundamentals of GIS, spatial data models, data input and topology, data analysis, and applications of GIS. The objectives are to introduce GIS fundamentals and processes of data management, analysis, and output. Students will learn about spatial data structures, data quality standards, and tools for data input, analysis, and management. The course aims to provide knowledge of GIS concepts and techniques.
The document discusses the application of remote sensing and geographical information systems (GIS) in civil engineering. It provides definitions of remote sensing as remotely sensing objects on Earth and GIS as a system to capture, store, analyze and present geographically referenced data. The document outlines some basic concepts of GIS including its origins from technologies like computer-aided cartography and databases. It also discusses data types in GIS like spatial data, attributes and different data models. Common software, functional elements and applications of GIS in areas like facilities management and environmental planning are summarized as well.
Topographic Information System as a Tool for Environmental Management, a Case...iosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online.
This document provides an introduction to Geographic Information Systems (GIS). It defines GIS as a system designed to store, manipulate, analyze and display spatially referenced data. The key components of a GIS are hardware, software and data. Common GIS software includes desktop programs like ArcGIS and open-source options like QGIS. GIS can incorporate different types of spatial data like raster, vector and remote sensing data along with associated attribute tables. Example applications discussed are in hydrology, including watershed analysis and flood modeling.
Comparison among Height Observation of GPS, Total Station and Level and their...IRJET Journal
This document compares the accuracy of GPS, total station, and level instruments for measuring elevation in mining works by using GIS technology. Statistical analysis showed the level measurements had the lowest variation while GPS had the highest. Topographic maps were created from observations from each instrument, showing they produced similar overall elevation patterns. The document concludes that while GPS and total station measurements have some error, their accuracy is sufficient for mining works. GIS allows easy analysis and use of elevation data from any of the three instruments.
A Solution to Land Area Calculation for Android Phone using GPS-Luwei YangLuwei Yang
This document proposes an Android application to calculate land area using GPS. It records a user's path using GPS as they walk around a land area. It then calculates the total land area using the trapezoid method, which breaks the irregular shape into smaller trapezoids. The Kalman filter is used to improve GPS accuracy and reduce errors, achieving an average error of 3.64% in tests. Key aspects include using Gauss-Kruger projection to convert GPS coordinates to plane coordinates before area calculation, and employing the trapezoid method and Kalman filtering to accurately calculate irregular land shapes and compensate for GPS errors, respectively.
The document discusses using GIS for a bridge inventory project for the City of New Haven, CT. Key project elements included collecting location and condition data for bridges during site visits, developing a database and summary reports, prioritizing bridges, and delivering the results in a digital map format to help the city manage its bridge infrastructure. The GIS approach integrated data on bridge locations, conditions and priorities to provide a comprehensive inventory and assessment tool.
The document discusses GPS satellites, receivers, and software. It provides the following key details:
- GPS satellites orbit the Earth at about 20,000 km and there are 24 satellites that complete two orbits per day. They are operated by the US Air Force.
- GPS receivers accurately calculate location by receiving signals from the satellites. Initially for military use, most receivers are now in cars and smartphones.
- GPS navigation software provides turn-by-turn directions based on maps or tracks a user's location and allows preprogrammed routes.
- GPS devices indicate location, routes, traffic, places of interest and provide turn-by-turn navigation via maps and text or speech. They track location for
Mapping the Wind Power Density and Weibull Parameters for Some Libyan Citiesinventionjournals
In order to introduce a well-informed decision regarding positioning of wind farm projects, prior intensive data collection, processing, and analysis are required. In this paper, wind data of twenty-five Libyan cities has been collected, processed, and analyzed to determine Weibull distribution parameters and the wind energy density for each of the twenty-five cities. The study is based on a recorded historical data from NASA of air temperature, barometric pressure, and wind speed for ten years along the period from January 1 st, 2005 to December 31st, 2014. The data used are the daily average values for each of the three parameters. Three methods have been used to estimate Weibull parameters namely: 1) the power density method, 2) the maximum likelihood method, and 3) the moment method. The goodness-of-fit for each method is, then, compared using the mean absolute error and the root mean square error methods. Lack of information regarding wind energy surveys for this particular region was one of the key factors in conducting such a comprehensive analysis.
This document discusses flood modelling and prediction in Kerala using GIS and remote sensing. It provides background on Kerala's geography and climate, which causes frequent flooding. It then describes how GIS and remote sensing tools like digital elevation models, land use data, and rainfall data can be used as inputs to model flood inundation areas and predict future flooding. The outputs of these models, like flood extent maps, can help with disaster management and planning flood prevention measures.
Photogrammetry Survey- Surveying II , Civil Engineering StudentsPramesh Hada
Photogrammetry is the science of making measurements from photographs. It involves planning and taking photographs, processing the photographs, and measuring the photographs to produce results like maps and 3D models.
There are two main types of photographs used in photogrammetry - terrestrial and aerial photographs. Terrestrial photographs are taken from ground-based camera stations using a phototheodolite. Aerial photographs are taken from an airborne camera mounted on an aircraft and can be vertical or oblique.
Key applications of photogrammetry include topographic mapping, engineering surveys, geological mapping, and urban and regional planning due to its ability to cover large areas quickly and accurately.
The document discusses the application of geographic information systems (GIS) in natural resource management (NRM). It provides examples of how GIS is used for hazard and risk management like mapping forest fires, tsunamis, and soil erosion. GIS aids in change detection, natural resource inventories, and environmental monitoring. Case studies demonstrate how GIS has been applied to assess risks from hazardous waste transport and identify high traffic road sections. In summary, the document outlines the various uses of GIS technology in studying, analyzing, and managing natural resources and environmental risks.
This document provides an overview of geographical information systems (GIS) and their concepts. It discusses that GIS allows for the integration of spatial and non-spatial data in a digital format to aid decision making. Key points include that GIS represents geographic features as vector or raster data, integrates data from different sources by georeferencing to a common coordinate system, and can perform spatial analysis and modeling to answer questions about patterns and relationships. GIS is a useful tool for tasks like natural resource management, precision agriculture, and land use planning.
To create a 4Vcard profile, visit 4vcard.com and register an account by filling in basic contact details and services offered. The profile can then be customized by uploading an avatar photo, selecting a username, and previewing the public profile. The completed 4Vcard URL can be shared to promote translation services everywhere.
O documento discute a produção da informação na era digital. Apresenta conceitos como sociedade em rede, economia da informação, propriedade intelectual e softwares livres versus proprietários. Destaca que a internet descentralizou a produção e distribuição da informação, tornando-a um bem não rival e de baixo custo.
Pressurized accelerated extraction of pollutantsBhupander Kumar
Accelerated solvent extraction (ASE) is a technique that uses solvents, elevated temperatures, and pressures to efficiently extract analytes from solid samples. It provides several advantages over traditional techniques like Soxhlet extraction, including requiring smaller sample and solvent volumes and shorter extraction times. Key factors that influence ASE extraction include sample preparation, solvent selection, temperature, pressure, static time, flush volume, and number of cycles. These parameters require optimization for different sample matrixes and target analytes. ASE is useful for extracting pesticides, PAHs, PCBs, and dioxins from soils, sediments, plants and other solid environmental samples.
This study analyzed the effects of increased water temperature and other climate change stressors on the embryonic development of the marine invertebrate Ciona intestinalis. Sea squirts were reared in tanks at the projected increased temperature of 22°C and the normal temperature of 18°C. Their embryos were exposed to varying salinity and pH levels. Preliminary results suggest embryos from sea squirts reared at 22°C exhibited less normal development, especially under altered salinity, compared to those from 18°C, indicating climate change may negatively impact the species' reproductive success through impaired embryonic development.
Slides de Estática para o Super supermedsartremoyses
O documento discute conceitos fundamentais de estática, incluindo centro de massa, equilíbrio de forças e momentos de força. Explica como calcular o momento de uma força em relação a um ponto usando a distância da força até esse ponto e a definição de equilíbrio estático para corpos extensos em termos da soma de todas as forças e momentos aplicados.
El documento presenta un plan de marketing que incluye un análisis de la situación del mercado, un análisis interno y externo de la empresa, una evaluación FODA, objetivos de ventas, posicionamiento y rentabilidad, la selección de estrategias de acuerdo con la posición en el mercado, y planes para implementar, presupuestar y supervisar el plan de marketing.
This document discusses the film opening that was created. It uses conventions from horror films such as Blair Witch Project and Texas Chainsaw Massacre. The opening features a black title screen with white text and static noise to set the mysterious tone. It shows the rural setting of a field and barn to introduce the lonely location. Costumes of typical camping gear add realism, and a hammer is used as the villain's weapon. Camerawork includes handheld shots to follow characters like Blair Witch. The opening sets up the storyline of teens getting lost in the barn and introduces characters similarly to Trainspotting.
Es wird immer schwieriger einen Job Zürich oder einen Job Glatttburgg zu finden, aus diesem Grund gibt es jetzt viele Unternehmen die für einen die geeignet Stens Jobs Zürich rausfiltern. Die Firma Gamapersonal z.B.: ist einer der gefragtesten Unternehmen in der Schweiz, deren Kunden sind immer zufriedene Kunden.
La SNCF ha creato iDBUS, un servizio pullman a lunga percorrenza che collega le principali città europee. Con corse regolari operate da pullman di ultima generazione, iDBUS ambisce ad una posizione di leader tra i fornitori europei di servizi di pullman a lunga percorrenza. I passeggeri troveranno a bordo comfort e accessibilità, attenzione e informazione. Un obiettivo fondamentale: reinventare l'esperienza dei passeggeri senza limitarsi al semplice conseguimento della soddisfazione del cliente.
El documento resume la historia de la colección de arte impresionista de Albert C. Barnes y la controversia actual sobre su traslado a un nuevo museo en el centro de Filadelfia. Barnes adquirió obras de Degas, Monet, Renoir y otros a bajo precio y construyó una fundación para exhibirlas, restringiendo el acceso. Ahora se planea mover la colección valuada en $6 mil millones a un nuevo edificio contra los deseos originales de Barnes.
El documento describe las redes sociales digitales y su uso para la educación en la Web 2.0. Explica conceptos clave como las teorías de grafos sociales y los seis grados de separación. También analiza plataformas como Ning que permiten crear redes sociales personalizadas, y los beneficios que estas redes pueden aportar a la educación, como mejorar la comunicación y fomentar un sentido de comunidad entre estudiantes y profesores.
Este documento apresenta a Best Answer Consulting, uma empresa de consultoria. Apresenta os serviços de consultoria estratégica, de gestão, controlo interno, incentivos, financiamentos e redução de custos que fornece. Inclui também informações sobre a equipa de consultores e os seus perfis profissionais.
Towards the Implementation of the Sudan Interpolated Geoid Model Khartoum Sta...ijtsrd
The discussions between ellipsoid and geoid have invoked many researchers during the recent decades, especially during the GNSS technology era, which had witnessed a great deal of development but still geoid undulation requires more investigations. To figure out a solution for Sudans local geoid, this research has tried to intake the possibility of determining the geoid model by following two approaches, gravimetric and geometrical geoid model determination, by making use of GNSS leveling benchmarks at Khartoum state. The Benchmarks are well distributed in the study area, in which, the horizontal coordinates and the height above the ellipsoid have been observed by GNSS while orthometric heights were carried out using precise leveling. The Global Geopotential Model GGM represented in EGM2008 has been exploited to figure out the geoid undulation at the benchmarks in the study area. This is followed by a fitting process, that has been done to suit the geoid undulation data which has been computed using GNSS leveling data and geoid undulation inspired by the EGM2008. Two geoid surfaces were created after the fitting process to ensure that they are identical and both of them could be counted for getting the same geoid undulation with an acceptable accuracy. In this respect, statistical operation played an important role in ensuring the consistency and integrity of the model by applying cross validation techniques splitting the data into training and testing datasets for building the geoid model and testing its eligibility. The geometrical solution for geoid undulation computation has been utilized by applying straightforward equations that facilitate the calculation of the geoid undulation directly through applying statistical techniques for the GNSS leveling data of the study area to get the common equation parameters values that could be utilized to calculate geoid undulation of any position in the study area within the claimed accuracy. Both systems were checked and proved eligible to be used within the study area with acceptable accuracy which may contribute to solving the geoid undulation problem in the Khartoum area, and be further generalized to determine the geoid model over the entire country, and this could be considered in the future, for regional and continental geoid model. Ahmed M. A. Mohammed. | Kamal A. A. Sami "Towards the Implementation of the Sudan Interpolated Geoid Model (Khartoum State Case Study)" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-8 | Issue-1 , February 2024, URL: https://www.ijtsrd.com/papers/ijtsrd63483.pdf Paper Url: https://www.ijtsrd.com/engineering/civil-engineering/63483/towards-the-implementation-of-the-sudan-interpolated-geoid-model-khartoum-state-case-study/ahmed-m-a-mohammed
This document summarizes a study that evaluated the accuracy of GPS and automatic level instruments for topographic surveying. The study collected elevation data using both instruments at points in a study area in Iraq. The data was input into GIS software to create contour maps and digital elevation models (DEMs) from each dataset. The accuracy of the DEMs was then evaluated and compared. The results showed the effect that the source data, DEM resolution, and ground control point distribution had on accuracy. This allowed the study to assess the relative accuracy and effectiveness of GPS versus automatic leveling for topographic data collection and DEM generation.
This document summarizes a study that evaluated the accuracy of GPS and automatic level instruments for topographic surveying. Researchers collected elevation data for 25 points in the study area using both a GPS receiver and an automatic level. They then used ArcGIS to create contour maps and digital elevation models from each dataset. The results showed that the GPS data had lower standard deviation and was therefore more accurate than the automatic level data. However, automatic leveling remains a cost-effective method for small study areas. The integration of GPS and GIS techniques allows for efficient processing and analysis of spatial data to produce high accuracy topographic maps and DEMs.
Need for Pan India Compatibility of Geospatial Databases in Terms of Map Proj...Mallikarjun Mishra
The present study is taken up to record variations in the extent of area of two polygons–(i)a ground measured area of a university campus, (ii)enclosing the Ganga basin and a polygon covering (iii)India to examine the changes in both shape and area–under different map projections with various parameters. The exercise brought forth interesting results. Depending on final ranks worked out based on minimum differences in extent of areas and shape distortion in the case of India, it is suggested to adopt either (i)LCC projection with Everest India-Nepal datum, First Standard Parallel (FSP) 24.50, Second Standard Parallel (SSP) 28.50, Latitude of Origin (LO) 16.253259, Central Meridian (CM) 80.8749 or (ii)LCC projection with WGS 84 datum, FSP 24.50, SSP 28.50, LO 16.253259, CM 80.8749 or (iii)Polyconic with Everest India-Nepal datum, CM 84.50, LO 13.00, for mapping both smaller areas on larger scales and larger areas on smaller scales.
Practical Local Geoid Modelling of Benin City, Nigeria from Gravimetric Obser...IJAEMSJORNAL
The geometric heights obtained from GNSS observations cannot be used for engineering works as they are not reduced to the geoid. This study presents practical local geoid modelling from gravimetric observations using the modified Stokes integral for engineering applications in Benin City. A total of 52 points were observed with GNSS receivers and a gravimeter to respectively obtain their positions and absolute gravity values. The theoretical gravity values of the points were computed on the Clarke 1880 ellipsoid to obtain their local gravity anomalies. The modified Stokes integral was applied to compute the geoid heights of the points. The combined topographic effect was applied to the computed geoid heights of the points to obtain their precise geoid heights. The mean of the precise geoid heights of the points was computed to obtain the local gravimetric geoid model of the study area. The determined geoid model was validated for its reliability as well as the accuracy using the RMSE index. It is recommended that the use of assumed, as well as handheld GPS receiver heights for engineering works should be totally abolished as this study has established the local geoid model of Benin City.
Differentiation between Global and Local Datum from Different aspect Nzar Braim
Differentiation between Global and Local Datum from Different aspect
Spatial professionals are required to deal with an increasingly wide range
of positioning information obtained from various sources including
terrestrial surveying, Global Navigation Satellite System (GNSS)
observations and online GNSS processing services. These positions refer
to a multitude of local, national, and global datums. A clear understanding
of the different coordinate reference systems and datums in use today and
the appropriate transformations between these are therefore essential to
ensure rigorous consideration of reference frame variations to
produce high-quality outcomes in spatial data analysis tasks.
Sudan Geodetic and Geospatial Reference Systemijtsrd
The development in information and satellite technologies and geospatial data productions of today, let the Sudan Survey Authority to study all available options for a change from its local datum, Adindan to a global reference frame to be in line with the United Nations Global Geospatial Information UNGGIM committee of expert recommendations. Sudan Survey Authority SSA finally adopted the ITRF2008 IGS2008 to be as the official Sudan Reference System SRS . The SRS shall be an accurate reference system for the unification of Sudan existing many geospatial reference systems and datums, geodetic networks and mapping products and to work closely with the international and regional geospatial communities. The Sudan adopted reference system shall assist the public and private sector institutions for improving their organizational integration, data sharing and data exchange capabilities as well as increasing the ability to link geospatial data infrastructure data sets based on common location data, including Sudan National Basemap, property and building surveys, utility surveys and setting outs, natural resources surveys, roads and infrastructure surveys, map productions and map updatings, as well as all what can be considered as geospatial and survey practices in Sudan. The new Sudan reference system ITRF2008 will be considered as a national Geodetic Reference Frame NGRF , which, shall help the geospatial community in Sudan to adopt the best practices in the fields of geomatics and geoinformation by enhancing the existing systems and adopting new technologies associated with common standards and specifications.The paper overviewed the technical considerations of the adopted Sudan Reference System and outlined the benefits of the unification of previous georeferencing systems and to eliminate the drawbacks of using many datums within the entire boundaries of Sudan. Kamal A. A. Sami "Sudan Geodetic and Geospatial Reference System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-6 , December 2023, URL: https://www.ijtsrd.com/papers/ijtsrd60142.pdf Paper Url: https://www.ijtsrd.com/engineering/other/60142/sudan-geodetic-and-geospatial-reference-system/kamal-a-a-sami
This document discusses geodesy and its types. Geodesy is the science of accurately measuring and understanding the Earth's geometric shape, orientation in space and gravitational field. It involves determining coordinates and land boundaries and is used for applications like engineering construction, topographic mapping, monitoring structures and crustal movement. The document outlines the responsibilities of geodesists and how the field has evolved with new technologies like GPS and satellites. It describes different types of geodesy including satellite geodesy and physical geodesy.
This document provides information about courses in geodesy and GNSS (Global Navigation Satellite Systems) positioning. The geodesy course covers topics like ellipsoidal geometry, map projections, coordinate systems, and geodetic datums. The objective is to understand the shape of the Earth and perform related computations. The GNSS positioning course is a continuation, introducing concepts like satellite geodesy and the GPS system. It aims to explain positioning methods and their applications. Both courses discuss required textbooks and cover topics like coordinate systems, geometry of the ellipsoid and sphere, direct and inverse geodetic problems, map projections, datums and datum transformations.
1) The document describes a method for mapping small land parcels using a UAV integrated with terrestrial geo-referencing. A UAV equipped with a camera flies over the area to be mapped while a total station on the ground measures the camera position to geo-reference the aerial photos.
2) Several UAV designs were considered, including fixed-wing and quadcopter, with quadcopter selected for its ability to hover, fly slowly, and synchronize photos with total station measurements. A quadcopter was outfitted with a camera, navigation system, and signaling lights cued to photo capture.
3) Photos are geo-referenced by measuring the camera position with a total station using trigonometric methods
Surveying for Civil engineering is a
particular type of surveying known as "land surveying", it is the
detailed study or inspection, as by gathering information through
observations, measurements in the field, questionnaires, or
research of legal instruments, and data analysis in the support of
planning, designing, and establishing of property boundaries.
Land surveying can include associated services such as mapping
and related data accumulation, construction layout surveys,
precision measurements of length, angle, elevation, area, and
volume, as well as horizontal and vertical control surveys, and
the analysis and utilization of land survey data. Surveyors use
various tools to do their work successfully and accurately, such
as total stations, robotic total stations, GPS receivers, prisms, 3D
scanners, radio communicators, handheld tablets, digital levels,
and surveying software.
Survey data can be directly entered into a GIS from digital
data collection systems on survey instruments. When data is
captured, the user should consider if the data should be captured
with either a relative accuracy or absolute accuracy, since this
could not only influence how information will be interpreted but
also the cost of data captured.
In this paper GIS maps were developed depending on the
field surveying data made for a two traverses. First one has ribs
less than 50m length and the other larger than 50m. Each
traverse is holding five times using five equipments and
instruments: Tape, Level, Digital level, Digital theodolite and
Laser tape. Also those maps were drawn by using both of ACAD
and ArcView softwares. Then a detail surveying map was
produced. The precision was computed for both traverses in each
method. Its value is range from 1/140 to 1/10000.
GPS Datum Conversion and Improvement in GPS Accuracyijsrd.com
GPS Positioning has numerous applications in the field of navigation and Geodesy.GPS positioning is mainly based on the different Geodetic Datum. This paper mainly discusses the improved datum conversion equations for the conversion of World Geodetic System (WGS-84) to Universal Transverse Mercator (UTM), vice versa and the reduction of errors introduced while datum conversion. By applying the different filters like Least Squares Algorithm (LSA), Kalman Filter (KF) and Modified Kalman Filter (MKF) a considerable improvement in consistency has been observed. Comparatively Modified Kalman Filter gives better accuracy in positioning.GPS coordinates data samples are collected in different environments like heavy traffic area, tall buildings area are taken to validate the results.
This document describes an open-source 3D solar radiation model called SURFSUN3D that has been integrated with a 3D Geographic Information System (GIS) to allow for interactive assessment of photovoltaic potential in urban areas. The model transforms 3D building surfaces into 2D raster maps to allow for conventional GIS solar radiation calculations on a cell-by-cell basis. It has been validated against a commercial solar modeling software and tested on a 3D model of Boston, demonstrating its ability to calculate solar radiation for selected buildings and surfaces and visualize the results.
Tarımsal Toprak Haritalama'da Jeofizik MühendisliğiAli Osman Öncel
1) The document discusses a study evaluating the reliability and reproducibility of electromagnetic induction (EMI) data collection.
2) The study compared data from two identical EMI instruments, the calibration methods of different individuals, and variations in calibration height.
3) The results showed significant differences between instruments, calibrations, and heights. This demonstrates the need for standardization of EMI data collection procedures to ensure reliable and reproducible data.
This document discusses analyzing the geometric dilution of precision (GDOP) for the Indian Regional Navigation Satellite System (IRNSS) to improve user positioning accuracy. It first provides background on IRNSS and how GDOP relates to satellite geometry and positioning accuracy. It then describes using Systems Tool Kit (STK) software to simulate IRNSS satellites over 24 hours and calculate GDOP values for optimal configurations of 4 satellites as well as all satellites in view at different times. The goal is to analyze which approach (4 satellites or all satellites) provides better user positioning accuracy on average.
This document discusses a study on assessing the quality of geospatial data obtained from unmanned aerial vehicles (UAVs). The study aimed to generate accurate 3D geospatial data from UAV images of a 5.26 km2 area near Banaras Hindu University in India. Two software programs, ArcGIS Pro and Pix4Dmapper, were used to process over 135 images taken with a DJI Mavic Pro drone. The positional and vertical accuracies of the UAV data were determined by calculating the root mean square error of checkpoint locations. The analysis found horizontal and vertical errors within an acceptable range, demonstrating that low-cost UAVs can be used to obtain accurate 3D spatial data for large-scale mapping
This document describes a new robust fixed rank kriging (R-FRK) method for improving the spatial completeness and accuracy of satellite sea surface temperature (SST) products. The R-FRK method addresses two key issues: 1) it allows for dimension reduction kriging to be applied to satellite SST data over irregular regions, and 2) it incorporates a data-driven bias correction model to address systematic biases in the satellite SST measurements. The method is applied to Moderate Resolution Imaging Spectroradiometer (MODIS) SST data from 2003 and 2010. Validation using drifting buoy observations shows the method produces spatially complete SST fields with high accuracy.
Land Use/Land Cover Mapping Of Allahabad City by Using Remote Sensing & GIS IJMER
The present study was carried out to produce and evaluate the land use/land cover maps by on
screen visual interpretation. The studies of land cover of Allahabad city (study area) consist of 87517.47 ha
out of which 5500.35 ha is build up land (Urban / Rural) Area. In this respect, the Build up land (Urban /
Rural) area scorers 6.28% of the total area. It has also been found that about 17155.001ha (19.60 %) of
area is covered by current fallow land. The double/triple crop land of 30178.44ha (34.84%). The area
covered by gullied / ravines is 1539.20 ha (1.75 %) and that of the kharif crop land is 2828.00 ha (3.23 %).
The area covered by other wasteland is 2551.05ha (2.91%). Table 4.1 shows the area distribution of the
various land use and land cover of Allahabad city.
1) GNSS CORS networks provide continuously operating reference stations that allow real-time positioning and link regional networks to global reference frames like ITRF.
2) The paper discusses procedures for transforming positions between reference frames like ITRF, and outlines positioning services that can be provided by GNSS CORS networks.
3) GNSS CORS networks are important for geoscience applications requiring accurate, real-time positioning tied to a geodetic datum.
DGPS improves upon standard GPS accuracy by using a fixed reference station to calculate and broadcast differential corrections for errors caused by atmospheric delays of GPS signals. Receivers equipped with DGPS can then apply these corrections to achieve sub-meter accuracy, as low as 10 cm in some cases. It works by having a stationary receiver at a known location calculate differential errors compared to GPS satellites and broadcasting correction signals to enable mobile DGPS receivers to determine their position with much greater precision.
In our second session, we shall learn all about the main features and fundamentals of UiPath Studio that enable us to use the building blocks for any automation project.
📕 Detailed agenda:
Variables and Datatypes
Workflow Layouts
Arguments
Control Flows and Loops
Conditional Statements
💻 Extra training through UiPath Academy:
Variables, Constants, and Arguments in Studio
Control Flow in Studio
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/temporal-event-neural-networks-a-more-efficient-alternative-to-the-transformer-a-presentation-from-brainchip/
Chris Jones, Director of Product Management at BrainChip , presents the “Temporal Event Neural Networks: A More Efficient Alternative to the Transformer” tutorial at the May 2024 Embedded Vision Summit.
The expansion of AI services necessitates enhanced computational capabilities on edge devices. Temporal Event Neural Networks (TENNs), developed by BrainChip, represent a novel and highly efficient state-space network. TENNs demonstrate exceptional proficiency in handling multi-dimensional streaming data, facilitating advancements in object detection, action recognition, speech enhancement and language model/sequence generation. Through the utilization of polynomial-based continuous convolutions, TENNs streamline models, expedite training processes and significantly diminish memory requirements, achieving notable reductions of up to 50x in parameters and 5,000x in energy consumption compared to prevailing methodologies like transformers.
Integration with BrainChip’s Akida neuromorphic hardware IP further enhances TENNs’ capabilities, enabling the realization of highly capable, portable and passively cooled edge devices. This presentation delves into the technical innovations underlying TENNs, presents real-world benchmarks, and elucidates how this cutting-edge approach is positioned to revolutionize edge AI across diverse applications.
inQuba Webinar Mastering Customer Journey Management with Dr Graham HillLizaNolte
HERE IS YOUR WEBINAR CONTENT! 'Mastering Customer Journey Management with Dr. Graham Hill'. We hope you find the webinar recording both insightful and enjoyable.
In this webinar, we explored essential aspects of Customer Journey Management and personalization. Here’s a summary of the key insights and topics discussed:
Key Takeaways:
Understanding the Customer Journey: Dr. Hill emphasized the importance of mapping and understanding the complete customer journey to identify touchpoints and opportunities for improvement.
Personalization Strategies: We discussed how to leverage data and insights to create personalized experiences that resonate with customers.
Technology Integration: Insights were shared on how inQuba’s advanced technology can streamline customer interactions and drive operational efficiency.
Freshworks Rethinks NoSQL for Rapid Scaling & Cost-EfficiencyScyllaDB
Freshworks creates AI-boosted business software that helps employees work more efficiently and effectively. Managing data across multiple RDBMS and NoSQL databases was already a challenge at their current scale. To prepare for 10X growth, they knew it was time to rethink their database strategy. Learn how they architected a solution that would simplify scaling while keeping costs under control.
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...DanBrown980551
This LF Energy webinar took place June 20, 2024. It featured:
-Alex Thornton, LF Energy
-Hallie Cramer, Google
-Daniel Roesler, UtilityAPI
-Henry Richardson, WattTime
In response to the urgency and scale required to effectively address climate change, open source solutions offer significant potential for driving innovation and progress. Currently, there is a growing demand for standardization and interoperability in energy data and modeling. Open source standards and specifications within the energy sector can also alleviate challenges associated with data fragmentation, transparency, and accessibility. At the same time, it is crucial to consider privacy and security concerns throughout the development of open source platforms.
This webinar will delve into the motivations behind establishing LF Energy’s Carbon Data Specification Consortium. It will provide an overview of the draft specifications and the ongoing progress made by the respective working groups.
Three primary specifications will be discussed:
-Discovery and client registration, emphasizing transparent processes and secure and private access
-Customer data, centering around customer tariffs, bills, energy usage, and full consumption disclosure
-Power systems data, focusing on grid data, inclusive of transmission and distribution networks, generation, intergrid power flows, and market settlement data
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Connector Corner: Seamlessly power UiPath Apps, GenAI with prebuilt connectorsDianaGray10
Join us to learn how UiPath Apps can directly and easily interact with prebuilt connectors via Integration Service--including Salesforce, ServiceNow, Open GenAI, and more.
The best part is you can achieve this without building a custom workflow! Say goodbye to the hassle of using separate automations to call APIs. By seamlessly integrating within App Studio, you can now easily streamline your workflow, while gaining direct access to our Connector Catalog of popular applications.
We’ll discuss and demo the benefits of UiPath Apps and connectors including:
Creating a compelling user experience for any software, without the limitations of APIs.
Accelerating the app creation process, saving time and effort
Enjoying high-performance CRUD (create, read, update, delete) operations, for
seamless data management.
Speakers:
Russell Alfeche, Technology Leader, RPA at qBotic and UiPath MVP
Charlie Greenberg, host
Must Know Postgres Extension for DBA and Developer during MigrationMydbops
Mydbops Opensource Database Meetup 16
Topic: Must-Know PostgreSQL Extensions for Developers and DBAs During Migration
Speaker: Deepak Mahto, Founder of DataCloudGaze Consulting
Date & Time: 8th June | 10 AM - 1 PM IST
Venue: Bangalore International Centre, Bangalore
Abstract: Discover how PostgreSQL extensions can be your secret weapon! This talk explores how key extensions enhance database capabilities and streamline the migration process for users moving from other relational databases like Oracle.
Key Takeaways:
* Learn about crucial extensions like oracle_fdw, pgtt, and pg_audit that ease migration complexities.
* Gain valuable strategies for implementing these extensions in PostgreSQL to achieve license freedom.
* Discover how these key extensions can empower both developers and DBAs during the migration process.
* Don't miss this chance to gain practical knowledge from an industry expert and stay updated on the latest open-source database trends.
Mydbops Managed Services specializes in taking the pain out of database management while optimizing performance. Since 2015, we have been providing top-notch support and assistance for the top three open-source databases: MySQL, MongoDB, and PostgreSQL.
Our team offers a wide range of services, including assistance, support, consulting, 24/7 operations, and expertise in all relevant technologies. We help organizations improve their database's performance, scalability, efficiency, and availability.
Contact us: info@mydbops.com
Visit: https://www.mydbops.com/
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For more details and updates, please follow up the below links.
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Session 1 - Intro to Robotic Process Automation.pdfUiPathCommunity
👉 Check out our full 'Africa Series - Automation Student Developers (EN)' page to register for the full program:
https://bit.ly/Automation_Student_Kickstart
In this session, we shall introduce you to the world of automation, the UiPath Platform, and guide you on how to install and setup UiPath Studio on your Windows PC.
📕 Detailed agenda:
What is RPA? Benefits of RPA?
RPA Applications
The UiPath End-to-End Automation Platform
UiPath Studio CE Installation and Setup
💻 Extra training through UiPath Academy:
Introduction to Automation
UiPath Business Automation Platform
Explore automation development with UiPath Studio
👉 Register here for our upcoming Session 2 on June 20: Introduction to UiPath Studio Fundamentals: https://community.uipath.com/events/details/uipath-lagos-presents-session-2-introduction-to-uipath-studio-fundamentals/
"Scaling RAG Applications to serve millions of users", Kevin GoedeckeFwdays
How we managed to grow and scale a RAG application from zero to thousands of users in 7 months. Lessons from technical challenges around managing high load for LLMs, RAGs and Vector databases.
Discover top-tier mobile app development services, offering innovative solutions for iOS and Android. Enhance your business with custom, user-friendly mobile applications.
Crafting Excellence: A Comprehensive Guide to iOS Mobile App Development Serv...
G0343052058
1. International Journal of Computational Engineering Research||Vol, 03||Issue, 4||
www.ijceronline.com ||April||2013|| Page 52
Geoidal Map and Three Dimension Surface Model Part of Port
Harcourt Metropolis from “Satlevel” Collocation Model
Olaleye J. B.1
, J. O. Olusina1
, O. T. Badejo1
and K. F. Aleem2, 3
1
Department of Surveying and Geoinformatics, University of Lagos. Akoka - Lagos, Nigeria
2
Department of Geomatics Engineering Technology, Yanbu Industrial College, Yanbu Industrial City, Saudi
Arabia
3
Surveying and Geoinformatics Programme, Abubakar Tafawa Balewa University, Bauchi Nigeria
I. INTRODUCTION
1.1 Geoidal Map:
A Geoidal map is similar to contour map which is made up of contour lines depicting the value of
geoid for any points on the earth‟s surface. While heights of points above the Mean Sea Level (MSL) are used
for producing contour map, geoidal values at different points are used for producing geoidal map. Therefore,
any line on a geoidal surface is an imaginary line drawn on the geoidal map to connect points of the same
geoidal height on, above or below the earth surface. The accuracy required for such maps necessitates the
knowledge of the accurate and precise geoid at the same area. (Amin et al, 2005)
1.2. Geoid
The geoid is the surface which coincides with that surface to which the oceans would conform over the
entire earth, if free to adjust to the combined effects of the earth's mass attraction (gravitation) and the
centrifugal force of the Earth's rotation. Specifically, it is an equipotential surface, meaning that it is a surface on
which the gravitational potential energy has the same value everywhere with respect to gravity. The geoid
surface is irregular, but considerably smoother than earth's physical surface. Sea level, if undisturbed by tides,
currents and weather, would assume a surface equal to the geoid when the observation is carried out for a
numbers of years, usually 18.61years. (Deakin, 1996, Olaleye et al, 2010; Aleem, 2013)
Determination of the geoid has been one of major challenges of geodesists. Gravity data have been
used in the past with stokes integration and other approaches to determine the geoid. One of such conventional
methods was used by Hirvonen (1934) to carry out the first computation on a worldwide scale. He computed the
geoidal undulation for 62 points distributed in an East –West band encircling the entire earth surface. For the
first time, mean free air anomalies were estimated from the available gravity data covering 5˚ by 5˚ blocks.
Also, Tanni (1948 and 1949) used large quantity of gravity data to compute the global geoidal heights. He
employed the Prat-Hayford system‟s gravity reduction method and Airy Heiskanen system. He later computed
the global geoidal undulation in 5˚ by 5˚ blocks with a more detailed 1˚ by 1˚ blocks geoid for Europe.
Furthermore, Heiskanen (1957) computed the gravimetric geoid of Columbus using Free Air anomalies.
Abstract:
Geoidal map depicts the geoid configuration of the area under study. Data acquisition for
the production of such maps has been very tedious, time consuming and expensive with the use of
conventional methods. "Satlevel" Collocation is a new method of geoid determination in which the
ellipsoidal height from any satellite based system is combined with orthometric height from geodetic
levelling to model the geoid. The method enables the geoid to be determined in patches. Geoid so
determined can be applied with ellipsoidal height to get orthometric height which height users
always prefer . In this work, "Satlevel" Collocation model along with the user’s interactive computer
program “Orthometric Height on Fly”, were used to generate geoidal values in part of Port
Harcourt metropolis. The generated data was used to produce the Contour map of the study area
using SURFER software. The map was overlaid on the Local government map of Rivers State of
Nigeria. The production of Geoidal map from "Satlevel" Collocation is easier than the conventional
methods, when the initial geoidal coefficients have been determined. This method can be extended to
other parts of Nigeria and the world at large.
Keywords: Collocation, Geoid, Geoidal Map, Modelling “Satlevel‟, Three Dimension and SURFER
2. Geoidal Map and Three Dimension Surface Model Part…
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According to Heiskanen and Moritz (1967), five times gravity data more than Tanni (1934) was
available in the work of Heiskanen (1957), who also used electronic compute for numerical integration of
Stoke‟s formula. The geoidal map was produced to depict the geoidal configuration worldwide. Amin et al
(2005) predicted the gravimetric geoid and produce the precise geoidal map of the Toshka sector in Southern
part of Egypt using least square collocation. Also, Geodesy Group of University of Lagos (GGU, 2006)
produced the geoidal map of Nigeria as part of their submissions for the Optimum geoid for Nigeria using
classical method (Gravimetric and Earth Geopotential Model 1996 (EGM 96)).
However, it was observed that the classical and conventional methods are time consuming, expensive
and laborious. Also, Amin et al, (2005) noted the common defects of all classical techniques for geoid
determination such as the inadequate and inhomogeneous distribution of the used geodetic data. The
disadvantages have prevented the widespread use of these methods and hence the advent of simpler and
convenient methods such as the use of Global Navigation Satellite System (GNSS) combined with geodetic
levelling. GNSS provide WGS84 ellipsoidal heights and when compared with orthometric heights, from
geodetic levelling, it allows for the computation of the geoid, or the geoid-ellipsoid separation in the region of
the survey (Aleem, 1996; Olaleye et al, 2010; Aleem et al, 2011). These height differences were used to derive
the geoidal models called “satlevel” collocation model by Aleem (2013). The geoid model will give geoidal
undulation at every point of observation. This can be substituted with the ellipsoidal height from GNSS
observation to get the orthometric height as given in Equation 1:
N = h - H (1)
Where:
H = Orthometric height
h = Ellipsoidal height
N = geoidal height
From Equation 1, geoidal height can be computed which can be plotted on the map in form of spot heights. The
geoidal at each point can be interpolated to produce the Geoidal map.
1.3 Interpolation of Geoidal Values:
Interpolations of geoidal undulations follow the same procedures as interpolations of contours which
are often done by rough estimate. The procedure is to first plot all the available geoidal heights as point data on
the map and estimate the point for the undulation. However, a more accurate but time consuming method used
to be adopted is to use the formula for drafting contour which can be adopted for geoidal map as given by
Aleem (2011):
D
PC i
Z
(2)
Where:
PC is distance from one of the spot height to the point of geoidal line will pass.
D is the distance between two spot heights
Z is the difference between the two spot heights
i is the difference between the geoidal line and one of the Spot heights.
Distance PC will then be scaled and marked on the map, which are later connected to form the geoidal line.
1.4 Significance
Geoidal maps are effective for displaying the geoidal configuration of a place. This is significance in
geophysical study as it portrayed the geopotential configuration of the area under study. Therefore, it enhances
the analysis of geological structures of the area.
This study is also significant because it reduces the rigour of data acquisition each time the geoidal map of the
area is to be produced, when the geoidal coefficients have been determined. The use of software developed by
the Author will enhance the productivity.
1.5 Software Adopted for Geoidal Map:
There are different types of software in the market for production of contour, digital terrain and three
dimensional surface model. Any of these software can be used for production of geoidal map. This study used
Surfer software.
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1.5.1 Surfer.
Surfer is a Contouring and 3D surface mapping software package from Golden Software Incorporation
can transform random surveying data, using interpolation, into continuous curved face Contour. Surfer‟s
sophisticated interpolation engine transforms your XYZ data into publication-quality maps. It is provided with
eighteen different gridding/trend surface algorithms. The methods were grouped into smoothing and exact
interpolators. Smoothing interpolators are: Inverse Distance to a Power, Kriging , Polynomial Regression,
Radial Basis Function, Modified Shepard's Method, Local Polynomial, Moving Average; while the exact
interpolators are: Inverse Distance to a Power, Kriging, Nearest Neighbor, Radial Basis Function, Modified
Shepard's Method, Triangulation with Linear Interpolation, and Natural Neighbor. Any of these interpolation
methods can be used to approximate the geoid in an area, if adequate data are available. Surfer provides more
gridding methods and more control over gridding parameters. Recent edition has added conversion and
combination of maps with different coordinate systems.
1.5.2 Other Contour Map Software for Production of Geoidal Map
Other Contour Map Software that can be adopted for production of geoidal map may include: 3DField,
Garmin Basemap, mapviewer, Contour storyteller, Function Grapher, Auto plotter, Visual data, Filter test,
AutoDEM Li Contour and several other software are available for production of Contour map. Any of these
software can also be used for the production of geoidal map of the study area.
II. THE STUDY AREA
Port Harcourt lies on Latitude: 4°45'N and 5°02'N and Longitude: 6°52'E and 7°09'E. It is the seat of
Rivers State Government in oil rich Niger delta. Many companies, business organizations and government
agencies locate and operate their corporate offices. Many of these organisations have used the services of
surveyors for projects that needed height information. The surveyors, unable to get a bench mark to connect,
will simply establish a local datum to do the work. This practice has created a situation where many different
height values, which are irreconcilable, exist in the area. Therefore, this work reviews the need for simple
method of obtaining values for the benchmark, which this study is trying to solve. The points used for the study
were plotted on the local government map of Rivers State to show the distribution of points (Figure 1).
Figure 1: The Distribution of Points Used for the Study in Port Harcourt
III. METHODOLOGY
3.1 Materials and Data
The equipment needed for the exercise are:
GNSS receiver and its accessories to acquire data for ellipsoidal height
Level and its accessories to acquire data for orthometric height
Computer and its accessories for computation and analysis
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Surfer software for plotting the geoidal values.
Any software or program that can implement least square adjustment.
In this work Microsoft Office excel was used for all the computations, However Aleem, (2013) has
developed a computer program for all the procedures called “Orthometric Height on Fly”. This was used to
validate the results.
3.2 Data Acquisition
Levelling operation was carried out to obtain data for orthometric height.
GNSS observation was carried out to acquire geodetic coordinates which includes the geodetic latitude (ϕ),
geodetic longitude (λ) and ellipsoidal height (h). 86 points with good spatial distribution within the study area
were covered.
Other relevant data such constant for semi major axis, flattening and other parameter for the World Geodetic
System WGS84 referenced ellipsoid were collected from various literatures and INTERNET websites for data
analysis and processing.
3.3 Data Processing
Levelling reduction was carried; to obtain height of each point. These heath data were assumed to be
the orthometric height.
GNSS observation was processed to get the three dimensional coordinates, the geodetic latitude (ϕ), geodetic
longitude (λ) and ellipsoidal height (h), which were used in “satevel” collocation model.
3.4 “Satlevel” Collocation Model:
“Satlevel” Collocation model was developed by Aleem, (2013). The model is of the form:
3 2 3 2
1
3 2 2 3
2
2 3 2 2
3
cos cos sin cos cos cos cos sin cos cos
cos sin sin cos sin cos cos sin sin cos
cos sin sin cos sin sin sin
i L i i i i i i i i i
i i i i i i i i i i
i i i i i i i i
N N A
A
A r
(3)
Where:
NL is the long wavelength part of the geoid undulation in the area.
A1, A2 and A3 are the geoidal coefficients which are unknown coefficients to be determined.
ϕ and λ are the WGS „84 geodetic coordinates (Latitudes and Longitudes)
ri is residue at an observation point.
The “satlevel” collocation model geoidal coefficients of the area were computed using least squares adjustment
observation equation method.
The “satlevel” collocation model geoidal coefficients were used to compute the geoidal undulation (Table 1) of
each point in the area.
The geoidal undulations were plotted into a chart (Figure 3) to form the geoidal surface.
The geoidal undulation generated from “satlevel” collocation and the geodetic coordinates of the area were
plotted into geoidal map using Surfer software (Figure 4).
Three dimensional geoid surface model (Figure 5) was plotted using the geoidal undulation and the Geodetic
coordinates (Table 1)
IV. Results and Discussions
4.1 Results
The results of the orthometric heights acquired from the geodetic levelling and ellipsoidal heights from
GNSS observation were substituted into Equation 1 to obtain the values of the geoidal undulation as shown in
Tables 1.
Table 1: Sample of Orthometric heights and Geoidal Undulations of some of the Stations
Stations Latitude [o
] Longitude [o
] Ellipsoidal Heights (h) [m] Orthometric Heights (H) [m] Geoid (N) [m]
GPS 02 4.988341858 7.005441514 42.542 23.638 18.904
GPS 03 4.981133603 6.949840522 40.065 21.24 18.825
GPS 04 4.972244803 6.951180808 38.771 19.938 18.833
GPS 05 4.988165797 6.959676808 41.357 22.523 18.834
GPS 06 4.976870211 6.950525386 39.485 20.657 18.828
GPS 07 4.968417417 6.950765697 38.351 19.516 18.835
GPS 08 4.956065461 6.949389547 36.427 17.585 18.842
GPS 60 4.91610835 6.881154569 20.982 02.189 18.793
XSV 662 4.873506919 6.99841315 27.603 08.648 18.955
ZVS 3003 4.847971022 7.047811589 32.308 13.282 19.026
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Geoidal undulation for the “Satlevel” Collocation (Table 2) model was computed using Equation 3 for Port
Harcourt metropolis.
Table 2: Sample of Local and “Satlevel” Collocation Geoidal Undulations
STATIONS Geoidal Undulation computed from Equation (1)
[m]
“Satlevel” Geoidal Undulation Computed from Equation (3)
[m]
Residuals
GPS 02 18.9040 18.8910 0.013
GPS 03 18.8250 18.8288 -0.0038
GPS 04 18.8330 18.8368 -0.0038
GPS 05 18.8340 18.8360 -0.002
GPS 06 18.8280 18.8327 -0.0047
GPS 07 18.8350 18.8390 -0.004
GPS 08 18.8420 18.8457 -0.0037
GPS 60 18.7930 18.7817 0.0113
XSV 662 18.9550 18.9548 0.0002
ZVS 3003 19.0260 19.0229 0.0031
The data acquired Table (1) were used to plot chart (Figure 2):
The values of the Geoidal coefficients computed using least square adjustment observation equation as:
NL= -5477.15802
A1= 2714.485748
A2= 375.21354
A3= 214.34789
The results of the “satlevel” collocation geoidal undulations were plotted into chart (Figure 3):
The “Satlevel” collocation Geoidal map (Figure 4):
The geoidal map from geoidal undulation in Table 1 of Port Harcourt was plotted and overlaid on the Local
Government map of Rivers State
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Figure 4: Geoidal Map Plotted From “Satlevel” Collocation Model for Port Harcourt
The 3-D Geoid surface Model (Figure 5) was also plotted using Surfer software.
Figure 5: Three Dimensional Geoid Surface Model of part of Port Harcourt Metropolis
4.2 Discussion
Data Quality Validation. Verification of data quality is an important part of any geodetic and scientific
research, as it helps to be ensuring that the data used in the models are accurate enough to satisfy the
requirement of the application at hand. Data validation will assist in identification of suspicious and invalid
cases such as outliers, variables, and data values in the active data set. Data acquisition for Geodetic levelling
and DGPS were carried out by experienced surveyors, specifications for first order accuracy were strictly
followed. The data were checked and the mean of height differences were taken as the most probable value of
measurements. Therefore, the good quality of the data was guaranteed (Aleem, 2013).
Ellipsoidal and orthometric heights were plotted inform of chart (Figure 4). The chart displayed that ellipsoidal
and orthometric height follows the same pattern, which is an indication that the two surfaces are true
representation of the same terrain.
The geoidal surface (Figure 3) of the area was plotted of Port Harcourt Presence of outliers were noted in the
initial data were removed because they are more than 3 standard deviations (Heliani et al, 2004). The removals
of outliers make the chart to be smoother. The geoidal map was produced using SURFER software and overlaid
on the Local Government map of the Rivers State using Arc GIS software (Figure 4).
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V. CONCLUSION AND RECOMMENDATION
5.1 Conclusion
In this study, levelled heights were established along with GPS observation in some parts of Port
Harcourt to model the geoid in the study area. We have coordinated some of the points collocated with both
GNSS and levelling in the area. 'Satlevel" Collocation Model was used to get the geoidal coefficients, which
were used to get the geoidal undulation for each of the points. Ellipsoidal heights from GNSS observation were
used to get the orthometric heights, and used to plot the geoidal map with surfer software.
5.2 Recommendations
The area of coverage needs to be extended and more data should be acquired to improve the results.
Contracts for the production of maps should be awarded to the Institutions of Higher learning in the Nigeria.
This will enable the participating staff to acquire more experience and impart same to the students, so as to
improve the qualities of graduates for future challenges.
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