Creation and Spatial Analysis of 3D City Modeling based on GIS Data

The 3D city model is one of the crucial topics that are still under analysis by many engineers and programmers because of the great advancements in data acquisition technologies and 3D computer graphics programming. It is one of the best visualization methods for representing reality. This paper presents different techniques for the creation and spatial analysis of 3D city modeling based on Geographical Information System (GIS) technology using free data sources. To achieve that goal, the Mansoura University campus, located in Mansoura city, Egypt, was chosen as a case study. The minimum data requirements to generate a 3D city model are the terrain, 2D spatial features such as buildings, landscape area and street networks. Moreover, building height is an important attribute in the 3D extrusion process. The main challenge during the creation process is the dearth of accurate free datasets, and the time-consuming editing. Therefore, different data sources are used in this study to evaluate their accuracy and find suitable applications which can use the generated 3D model. Meanwhile, an accurate data source obtained using the traditional survey methods is used for the validation purpose. First, the terrain was obtained from a digital elevation model (DEM) and compared with grid leveling measurements. Second, 2D data were obtained from: the manual digitization from (30 cm) high-resolution imagery, and deep learning structure algorithms to detect the 2D features automatically using an object instance segmentation model and compared the results with the total station survey observations. Different techniques are used to investigate and evaluate the accuracy of these data sources. The procedural modeling technique is applied to generate the 3D city model. TensorFlow & Keras frameworks (Python APIs) were used in this paper; moreover, global mapper, ArcGIS Pro, QGIS and CityEngine software were used. The precision metrics from the trained deep learning model were 0.78 for buildings, 0.62 for streets and 0.89 for landscape areas. Despite, the manual digitizing results are better than the results from deep learning, but the extracted features accuracy is accepted and can be used in the creation process in the cases not require a highly accurate 3D model. The flood impact scenario is simulated as an application of spatial analysis on the generated 3D city model. Doi: 10.28991/CEJ-2022-08-01-08 Full Text: PD

Three dimensional modeling and geometric properties of oil plant equipment from terrestrial laser scanner observations

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

Non-penetrating deep sclerectomy versus combined trabeculotomy–trabeculectomy in primary congenital glaucoma

Background: The primary mode of therapy in children with primary congenital glaucoma (PCG) and mild or no corneal edema is goniotomy, which has a high success rate. However, in developing countries, the diagnosis of PCG is usually delayed, and corneal cloudiness interferes with goniotomy. Therefore, trabeculotomy may be the best choice in such eyes. We compared the short-term efficacy and safety of primary combined trabeculotomy–trabeculectomy (primary CTT) with that of non-penetrating deep sclerectomy (NPDS) in managing PCG. Methods: This prospective, randomized, comparative study included patients with PCG referred to Al-Azhar University Hospitals within a 1-year period. Eyes were randomly allocated to one of two groups: eyes in NPDS group underwent NPDS, and those in primary CTT group underwent primary CTT. Baseline and frequent postoperative assessments of intraocular pressure (IOP), cup-to-disc ratio (C/D ratio), corneal diameter, and axial length were performed for up to 6 months. The success rates were recorded in both groups. Results: Forty eyes of 26 patients were included, with 20 eyes allocated to each group. The mean (standard deviation) age of all patients was 12.9 (9.5) months, with comparable ages and sex ratios between groups (both P > 0.05). Both groups demonstrated a significant reduction in IOP and C/D ratio at each postoperative visit compared to the baseline visit (all P < 0.001), with no significant difference detected between the groups (all P > 0.05), except for a significantly lower IOP in NPDS group at 1 month (P < 0.05). The corneal diameter and axial length were comparable between groups at baseline and remained unchanged at all postoperative visits (all P > 0.05). The groups had comparable success rates (P > 0.05). No serious complications were detected. Conclusions: CTT and NPDS both yielded reasonable IOP control and reversal of cupping in eyes with PCG. We observed equal effectiveness of the surgical procedures without major safety concerns. Further large-scale clinical trials with longer follow-up periods are needed to verify our preliminary findings

USO DE RECEPTORES GPS DE 100 HZ NA DETECÇÃO DE DEFLEXÕES VERTICAIS MILIMÉTRICAS DE PONTES DE CONCRETO DE PEQUENO PORTE

As últimas quatro décadas foram importantes para o desenvolvimento da malha rodoviária brasileira. O país recebeu incentivos financeiros para a sua expansão e diversas soluções estruturais para pontes e viadutos foram criadas. Em paralelo a este desenvolvimento, houve nos últimos anos um crescimento significativo dessas estruturas em estágio avançado de deterioração devido à ausência de programas de manutenção preventiva. Dessa maneira, este trabalho propõe o uso de receptores GPS num plano de monitoramento de curta duração para acompanhar o comportamento estrutural de uma ponte rodoviária curva de concreto armado já em serviço. E apresenta os primeiros resultados da pesquisa com a portadora L1 do sistema GPS e dados gravados com taxa de 100 Hz, no monitoramento do vão central de ponte de concreto de pequeno porte situada sobre o Rio Jaguari, na cidade de Extrema, divisa entre os Estados de Minas Gerais e São Paulo. O desafio reside no fato de que estruturas como estas - pontes de concreto de pequeno e médio porte - respondem pela grande maioria das obras de arte da malha rodoviária brasileira e por serem estruturas rígidas, apresentam deflexões verticais pequenas, de até 5mm. O experimento foi realizado por meio de sessões de observações com receptores GPS sobre a ponte, no vão instrumentado por equipamentos convencionais para posterior confrontação de resultados entre os receptores GPS e os métodos clássicos de monitoramento. A ferramenta de filtragem Continuos Wavelet Transform (CWT) foi utilizada para analisar as frequências de resposta da ponte a partir dos resíduos da dupla diferença de fase da portadora L1. A análise do espectro de energia da CWT gerado a partir dos dados coletados com os receptores GPS indicou alta concentração de energia nas mesmas faixas de frequência - de resposta do tabuleiro da ponte - apontadas pela Modelagem por Elementos Finitos e pela prova de carga dinâmica

Approximation of gravitational calculation based on analytical models

Gravity meters can be used to measure all effects that make up the Earth’s gravity field. Many of these effects are caused by known sources such as the Earth’s rotation, distance from the Earth’s center, topographic relief, and tidal variation. Physical fields are the main component of many centuries of the paradigm of all of Earth Sciences. The changing gravitational field is very important subject of research in the scientific aspect and practical. This paper applies two analytical models to simplify the gravitation calculation, which are sphere and cone models. Examples and finite element applications for the two models are studied also and discussed. The results of this study reveal that the possibility of using the proposed method with using presented analytical, finite element and numerical models to estimate the better determination of the characteristics of the local gravity of natural and man-made objects of sizes up to several tens of kilometers

Structural damage detection of elevated circular water tank and its supporting system using geodetic techniques

Water is the main source of daily life for everyone and everywhere in the world. Sufficient water distribution depends on the place and design of water tank in certain areas. Water storage tanks are relatively flexible structures and they can tolerate greater settlements than other engineering structures. Deformation of tanks may cause severe damages to tank or even loss of life and injury to people, so monitoring the structural deformation and dynamic response of water tank and its supporting system to the large variety of external loadings has a great importance for maintaining tank safety and economical design of manmade structures. This paper presents an accurate geodetic observations technique to investigate the inclination of an elevated circular water tank and the deformation of its supporting structural system (supporting columns and circular horizontal beams) using reflector-less total station. The studied water tank was designed to deliver water to around 55000 person and has a storage capacity about 750 m3. Due to the studied water tank age, a non-uniform settlement of tank foundation and movement of pumps and electric machines under tank’s body will cause stress and strain for tanks membrane and settlement of sediments. So the studied water tank can tend to experience movement vertically, horizontally or both. Three epochs of observations were done (July 2014, September 2014 and December 2014). The results of the practical measurements, calculations and analysis of the interesting deformation of the studied elevated tanks and its supporting system using least squares theory and computer programs are presented. As a results of monitoring the water storage tank, circular reinforced concrete beams and columns at three monitoring epochs. The body of water storage tank has an inclination to the east direction and the value of inclination is increased with the time

Implementation of close range photogrammetry using modern non-metric digital cameras for architectural documentation

The development of applied geodetic techniques for mapping and documentation of historical structures, buildings and sites is an important and vital purpose for contribution of any recording of cultural heritage for any country such as Egypt. This is done to preserve and restore any valuable architectural or other cultural monument, as a support to architectural, archaeological and other art-historical research throughout the ages. The purpose of this paper is to use close range photogrammetry technique (CRP) to reconstruct 3D model of architectural and historical mosque facade and comparing the accuracy of using digital commercial non-metric cameras with different resolutions and metric camera with flatbed scanner and photogrammetric scanner for architectural building documentation. El-Nasr Mosque façade in Mansoura city, Egypt was chosen as a case study in this paper. At first, twenty five points were selected at mosque façade at different elevations and distributed at different façade surfaces and observed using total station. Some of these points were selected as control points and the others were selected as check points to validate the results. Effect of control point’s number on image processing and analysis is also studied. Three cameras positions were selected for imaging to get the full details of mosque façade. Close range Digital Workstation (CDW) program was used for processing and analysis of multiple images. The results are indicated that close range photogrammetry using metric camera with photogrammetry scanner instead of flatbed scanner in technique is accurate enough to be beneficial in 3D architectural building documentation. Digital cameras with CRP technique give up different accuracy that depends mainly on the resolution of cameras and camera specifications

Monitoring the change in land surface temperature and urban areas using Satellite images. Case study Kafr El-Sheikh City – Egypt

In recent years, the rate of urban growth has increased rapidly especially in Egypt, due to the increase in population growth. The Egyptian government has set up new cities and established large factories, roads and bridges in new places to solve this trouble. This paper investigates the change monitoring of land surface temperature, urban and agricultural area in Egypt especially Kafr EL-Sheikh city as case study using high resolution satellite images. Nowadays, satellite images are playing an important role in detecting the change of urban growth. In this paper, cadastral map for Kafr El-Sheikh city with scale 1:5000, images from Landsat 7 with accuracy 30 meters; images from Google Earth with accuracy 0.5 meter; and images from SAS Planet with accuracy 0.5 m are used where all images are available during the study period (for year’s 2003, 2006, 2009, 2012, 2015 and 2017). The analysis has been performed in a platform of Geographical Information System (GIS) configured with Remote Sensing system using ArcGIS 10.3 and ERDAS Imagine image processing software. From the processing and analysis of the specified images during the studied time period, it is found that the building area was increased by 28.8% from year 2003 up to 2017 from Google Earth images and increased by percentage 34.4% from year 2003 up to year 2017 from supervised Landsat 7 images but for unsupervised Landsat 7 images, the building area was increased by percentage 35.9%. In this study, land surface temperature (LST) was measured also from satellite images for different years through 2003 until 2017. It is deduced that the increase in the building area (urban growth) in the specified city led to increase the land surface temperature (LST) which will affect some agricultural crops. Depending on the results of images analysis, Forecasting models using different algorithms for the urban and agricultural area was built. Finally, it is deduced that integration of spacebased remote sensing technology with GIS tools provide better platform to perform such activities

Using fuzzy analytical hierarchy process for road transportation services management based on remote sensing and GIS technology

The importance of site selection for road transportation management and emergency services has been underscored, particularly in the wake of the global Covid-19 pandemic in addition to road accident injuries, which emphasized the need for swift patient, injured and wounded peoples transfer to hospitals. As a result, comprehensive road transportation management is essential during crises to ensure the safety and convenience of road users. To achieve effective road network management, a robust database is imperative. The aim of this study is to employ multi-criteria decision analysis with the aid of Geographical Information System (GIS) technology and remote sensing for the optimization of site selection for traffic signals, fire stations, and emergency services in Kafr El-Sheikh city, Egypt. The methodology incorporates two different methods which are Fuzzy Analytical Hierarchy Process (F-AHP) and the spline transformation method. The integration of Fuzzy set theory with AHP principles has given rise to a variant of AHP known as F-AHP. F-AHP combines qualitative and quantitative approaches. Fuzzy logic handles situations that are vague or poorly defined by assigning numerical values. Through the F-AHP approach, criteria that decision-makers unanimously deem “absolutely not important” in comparison to others are eliminated, allowing them to focus on the most significant criteria. As a case study, an Egyptian city was selected to apply these techniques. The results revealed multiple sites that were identified and selected through the applied analytical methods. These selected sites were also marked on the city map and verified in reality